Ng, Hooi Hooi; Leo, Chen Huei; Prakoso, Darnel; Qin, Chengxue; Ritchie, Rebecca H.; Parry, Laura J.
2017-01-01
Serelaxin prevents endothelial dysfunction in the mouse aorta ex vivo and inhibits apoptosis in cardiomyocytes under acute hyperglycaemia. Less is known about the effects of serelaxin in an in vivo mouse model of diabetes. Therefore, we tested the hypothesis in streptozotocin (STZ)-treated mice that serelaxin is able to reverse diabetes-induced vascular dysfunction and cardiac remodelling. Mice were divided into citrate buffer + placebo, STZ + placebo and STZ + serelaxin (0.5 mg/kg/d, 2 weeks) groups. After 12 weeks of diabetes, sensitivity to the endothelium-dependent agonist acetylcholine (ACh) was reduced in the mesenteric artery. This was accompanied by an enhanced vasoconstrictor prostanoid contribution and a decrease in endothelium-derived hyperpolarisation (EDH)-mediated relaxation. Serelaxin restored endothelial function by increasing nitric oxide (NO)-mediated relaxation but not EDH. It also normalised the contribution of vasoconstrictor prostanoids to endothelial dysfunction and suppressed diabetes-induced hyper-responsiveness of the mesenteric artery to angiotensin II. Similarly, diabetes reduced ACh-evoked NO-mediated relaxation in the aorta which was reversed by serelaxin. In the left ventricle, diabetes promoted apoptosis, hypertrophy and fibrosis; serelaxin treatment reversed this ventricular apoptosis and hypertrophy, but had no effect on fibrosis. In summary, serelaxin reversed diabetes-induced endothelial dysfunction by enhancing NO-mediated relaxation in the mouse vasculature and attenuating left ventricular hypertrophy and apoptosis. PMID:28067255
Clinical determinants and consequences of left ventricular hypertrophy.
Messerli, F H
1983-09-26
The left ventricle adapts to an increased afterload such as that produced by arterial hypertension with concentric left ventricular hypertrophy. However, this adaptive process can be modified by a variety of physiologic and pathophysiologic states. Progressive aging, black race, and perhaps disorders with an increased sympathetic outflow seem to accelerate left ventricular hypertrophy. Obesity and other high cardiac output states predominantly produce dilatation of the left ventricle, and their combination with arterial hypertension results in eccentric left ventricular hypertrophy. Similarly, endurance exercise increases left ventricular volume more than wall thickness, whereas isometric exercise produces an increase in wall thickness only. The presence or absence of some physiologic and pathogenetic factors has direct implication on the assessment of what constitutes a "normal" left ventricular structure and function. Left ventricular hypertrophy has been shown to increase ventricular ectopic impulse generation and to put patients at a high risk of sudden death. Moreover, the increase in myocardial mass lowers coronary reserve and enhances cardiac oxygen requirements. Thus, the presence of left ventricular hypertrophy has to be considered as an ominous sign rather than as a benign adaptive process.
Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy
Lanjewar, Swapnil S; Chhabra, Lovely; Chaubey, Vinod K; Joshi, Saurabh; Kulkarni, Ganesh; Kothagundla, Chandrasekhar; Kaul, Sudesh; Spodick, David H
2013-01-01
Background The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration. Methods We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups. Results There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy. Conclusion The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration. PMID:24293995
Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy.
Lanjewar, Swapnil S; Chhabra, Lovely; Chaubey, Vinod K; Joshi, Saurabh; Kulkarni, Ganesh; Kothagundla, Chandrasekhar; Kaul, Sudesh; Spodick, David H
2013-01-01
The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration. We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups. There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy. The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration.
Left ventricular hypertrophy diagnosed after a stroke: a case report.
Umeojiako, Wilfred Ifeanyi; Kanyal, Ritesh
2018-03-22
Stroke is a recognized clinical course of hypertrophic cardiomyopathy. This interesting case showed notable difference on the electrocardiogram of a patient 4 months prior to suffering a stroke and 10 days after suffering a stroke. The pre-stroke electrocardiogram showed atrial fibrillation with a narrow QRS complex, while the post-stroke electrocardiogram showed marked left ventricular hypertrophy. Left ventricular hypertrophy was diagnosed using the Sokolow-Lyon indices. The development of left ventricular hypertrophy a few days after suffering a stroke has not previously been reported. An 83-year-old white British woman with a background history of permanent atrial fibrillation, hypertension, and previous stroke attended the emergency department with a 2-day history of exertional dyspnea, and chest tightness. On examination, she had bibasal crepitations with a systolic murmur loudest at the apex. In-patient investigations include an electrocardiogram, blood tests, chest X-ray, contrast echocardiogram, coronary angiogram, and cardiovascular magnetic resonance imaging. An electrocardiogram showed atrial fibrillation, with inferolateral T wave inversion, and left ventricular hypertrophy. A chest X-ray showed features consistent with pulmonary edema. A contrast echocardiogram showed marked hypertrophy of the mid to apical left ventricle, appearance consistent with apical hypertrophic cardiomyopathy. Coronary angiography showed eccentric shelf-type plaque with non-flow-limiting stenosis in the left coronary artery main stem. Cardiovascular magnetic resonance imaging reported findings highly suggestive of apical hypertrophic cardiomyopathy. Our patient was treated and discharged on rivaroxaban, bisoprolol, and atorvastatin with a follow-up in the cardiomyopathy outpatient clinic. Electrocardiogram diagnosis of left ventricular hypertrophy led to the diagnosis of apical hypertrophic cardiomyopathy in this patient. Left ventricular hypertrophy was only evident a few days after our patient suffered a stroke. The underlying mechanisms responsible for this remain unclear. Furthermore, differential diagnosis of hypertrophic cardiomyopathy should be considered in people with electrocardiogram criteria for left ventricular hypertrophy. Cardiovascular magnetic resonance imaging is an important diagnostic tool in identifying causes of left ventricular hypertrophy. Family screening should be recommended in patients with new diagnosis of hypertrophic cardiomyopathy.
Chouabe, C; Amsellem, J; Espinosa, L; Ribaux, P; Blaineau, S; Mégas, P; Bonvallet, R
2002-04-01
Recent studies indicate that regression of left ventricular hypertrophy normalizes membrane ionic current abnormalities. This work was designed to determine whether regression of right ventricular hypertrophy induced by permanent high-altitude exposure (4,500 m, 20 days) in adult rats also normalizes changes of ventricular myocyte electrophysiology. According to the current data, prolonged action potential, decreased transient outward current density, and increased inward sodium/calcium exchange current density normalized 20 days after the end of altitude exposure, whereas right ventricular hypertrophy evidenced by both the right ventricular weight-to-heart weight ratio and the right ventricular free wall thickness measurement normalized 40 days after the end of altitude exposure. This morphological normalization occurred at both the level of muscular tissue, as shown by the decrease toward control values of some myocyte parameters (perimeter, capacitance, and width), and the level of the interstitial collagenous connective tissue. In the chronic high-altitude hypoxia model, the regression of right ventricular hypertrophy would not be a prerequisite for normalization of ventricular electrophysiological abnormalities.
Does load-induced ventricular hypertrophy progress to systolic heart failure?
Berenji, Kambeez; Drazner, Mark H; Rothermel, Beverly A; Hill, Joseph A
2005-07-01
Ventricular hypertrophy develops in response to numerous forms of cardiac stress, including pressure or volume overload, loss of contractile mass from prior infarction, neuroendocrine activation, and mutations in genes encoding sarcomeric proteins. Hypertrophic growth is believed to have a compensatory role that diminishes wall stress and oxygen consumption, but Framingham and other studies established ventricular hypertrophy as a marker for increased risk of developing chronic heart failure, suggesting that hypertrophy may have maladaptive features. However, the relative contribution of comorbid disease to hypertrophy-associated systolic failure is unknown. For instance, coronary artery disease is induced by many of the same risk factors that cause hypertrophy and can itself lead to systolic dysfunction. It is uncertain, therefore, whether ventricular hypertrophy commonly progresses to systolic dysfunction without the contribution of intervening ischemia or infarction. In this review, we summarize findings from epidemiologic studies, preclinical experiments in animals, and clinical trials to lay out what is known-and not known-about this important question.
Liu, Dan; Hu, Kai; Nordbeck, Peter; Ertl, Georg; Störk, Stefan; Weidemann, Frank
2016-05-10
Despite substantial advances in the imaging techniques and pathophysiological understanding over the last decades, identification of the underlying causes of left ventricular hypertrophy by means of echocardiographic examination remains a challenge in current clinical practice. The longitudinal strain bull's eye plot derived from 2D speckle tracking imaging offers an intuitive visual overview of the global and regional left ventricular myocardial function in a single diagram. The bull's eye mapping is clinically feasible and the plot patterns could provide clues to the etiology of cardiomyopathies. The present review summarizes the longitudinal strain, bull's eye plot features in patients with various cardiomyopathies and concentric left ventricular hypertrophy and the bull's eye plot features might serve as one of the cardiac workup steps on evaluating patients with left ventricular hypertrophy.
Garcia, Santiago; Akbar, Muhammad S; Ali, Syed S; Kamdar, Forum; Tsai, Michael Y; Duprez, Daniel A
2010-09-03
Left ventricular hypertrophy adversely affects outcomes in patients with hypertension. Whether N-terminal pro B-type natriuretic peptide (NT-proBNP) adds incremental prognostic information in patients with hypertension and left ventricular hypertrophy (LVH) is not well established. We aimed to study the prognostic value of NT-proBNP in hypertensive patients with LVH. Echocardiography was performed in 232 patients (mean age 61±15, 102 males, 130 females) for the diagnosis of left ventricular hypertrophy. Left ventricular mass was measured according to The American Society of Echocardiography guidelines. A blood sample was taken for NT-proBNP determination. NT-proBNP levels were analyzed in quartiles after log transformation. Long term survival was established by review of electronic medical records. Arterial hypertension was present in 130 patients (56%) and left ventricular hypertrophy was present in 105 patients (45%). In patients with left ventricular hypertrophy, NT-proBNP levels predicted long term survival (Chi-square=10, p=0.01). After adjusting by age, presence of coronary artery disease, ejection fraction, diabetes status, and hypertension; patients in highest NT pro-BNP quartile were twice as likely to die when compared to patients in the lowest NT-ptoBNP quartile (OR=2.2, 95% CI=1.0-4.6, p=0.03). NT-proBNP is an independent predictor of survival in patients with hypertension and increased left ventricular mass. Copyright © 2009 Elsevier B.V. All rights reserved.
Kawaguchi, Y
1985-04-01
QRS deflection area vector (Aqrs), T deflection area vector (At) and ventricular gradient (G) in right ventricular hypertrophy were studied in 53 subjects divided on the basis of cardiac catheterization data into four subgroups; normal controls, mild MS group, right ventricular pressure overload group and right ventricular volume overload group. Aqrs, At and G of the four subgroups were calculated using a microcomputer and compared. Aqrs in right ventricular pressure overload group and volume overload group was shifted to the right and slightly anteriorly from that in normal control group. At in right ventricular pressure overload group and volume overload group was shifted slightly upwards and significantly posteriorly from that in the normal control and mild MS groups. G in right ventricular pressure overload group and volume overload group was shifted to the right and significantly posteriorly from that in normal control and mild MS groups. Using multivariative analysis, we developed criteria for diagnosing right ventricular hypertrophy with At: 0.059At(Z) - 0.0145 [At] - 0.2608 less than or equal to 0. Application of this criteria achieved 82.4% (28 of 34) sensitivity in the patients with right ventricular hypertrophy and 90.9% (10 of 11) specificity in the normal control subjects.
Zhu, Y C; Zhu, Y Z; Spitznagel, H; Gohlke, P; Unger, T
1996-01-01
Left ventricular hypertrophy is considered to be an independent risk factor giving rise to ischemia, arrhythmias, and left ventricular dysfunction. Slow movement of intracellular calcium contributes to the impaired contraction and relaxation function of hypertrophied myocardium. Myofibril content may also be shifted to fetal-type isoforms with decreased contraction and relaxation properties in left ventricular hypertrophy. Myocyte hypertrophy and interstitial fibrosis are regulated independently by mechanical and neurohumoral mechanisms. In severely hypertrophied myocardium, capillary density is reduced, the diffusion distance for oxygen, nutrients, and metabolites is increased, and the ratio of energy-production sites to energy-consumption sites is decreased. The metabolic state of severely hypertrophied myocardium is anaerobic, as indicated by the shift of lactate dehydrogenase marker enzymes. Therefore, the hypertrophied myocardium is more vulnerable to ischemic events. As a compensatory response to severe cardiac hypertrophy and congestive heart failure, the ADP/ATP carrier is activated and atrial natriuretic peptide is released to increase high-energy phosphate production and reduce cardiac energy consumption by vasodilation and sodium and fluid elimination. However, in severely hypertrophied and failing myocardium, vasoconstrictor and sodium- and fluid-retaining factors, such as the renin-angiotensin system, aldosterone, and sympathetic nerve activity, play an overwhelming role. Angiotensin-converting enzyme inhibitors (ACEIs) are able to prevent cardiac hypertrophy and improve cardiac function and metabolism. Under experimental conditions, these beneficial effects can be ascribed mainly to bradykinin potentiation, although a contribution of the ACEI-induced angiotensin II reduction cannot be excluded.
Beetz, Nadine; Rommel, Carolin; Schnick, Tilman; Neumann, Elena; Lother, Achim; Monroy-Ordonez, Elsa Beatriz; Zeeb, Martin; Preissl, Sebastian; Gilsbach, Ralf; Melchior-Becker, Ariane; Rylski, Bartosz; Stoll, Monika; Schaefer, Liliana; Beyersdorf, Friedhelm; Stiller, Brigitte; Hein, Lutz
2016-12-01
Biglycan, a small leucine-rich proteoglycan, has been shown to play an important role in stabilizing fibrotic scars after experimental myocardial infarction. However, the role of biglycan in the development and regression of cardiomyocyte hypertrophy and fibrosis during cardiac pressure overload and unloading remains elusive. Thus, the aim of the present study was to assess the effect of biglycan on cardiac remodeling in a mouse model of left ventricular pressure overload and unloading. Left ventricular pressure overload induced by transverse aortic constriction (TAC) in mice resulted in left ventricular dysfunction, fibrosis and increased biglycan expression. Fluorescence- and magnetic-assisted sorting of cardiac cell types revealed upregulation of biglycan in the fibroblast population, but not in cardiomyocytes, endothelial cells or leukocytes after TAC. Removal of the aortic constriction (rTAC) after short-term pressure overload (3weeks) improved cardiac contractility and reversed ventricular hypertrophy but not fibrosis in wild-type (WT) mice. Biglycan ablation (KO) enhanced functional recovery but did not resolve cardiac fibrosis. After long-term TAC for 9weeks, ablation of biglycan attenuated the development of cardiac hypertrophy and fibrosis. In vitro, biglycan induced hypertrophy of neonatal rat cardiomyocytes and led to activation of a hypertrophic gene program. Putative downstream mediators of biglycan signaling include Rcan1, Abra and Tnfrsf12a. These genes were concordantly induced by TAC in WT but not in biglycan KO mice. Left ventricular pressure overload induces biglycan expression in cardiac fibroblasts. Ablation of biglycan improves cardiac function and attenuates left ventricular hypertrophy and fibrosis after long-term pressure overload. In vitro biglycan induces hypertrophy of cardiomyocytes, suggesting that biglycan may act as a signaling molecule between cell types to modulate cardiac remodeling. Copyright © 2016 Elsevier Ltd. All rights reserved.
Izgi, Cemil; Vassiliou, Vassilis; Baksi, A John; Prasad, Sanjay K
2016-11-01
Differential diagnosis of asymmetrical left ventricular hypertrophy may be challenging, particularly in patients with history of hypertension. A middle-aged man underwent an echocardiographic examination during workup for hypertension, which unexpectedly showed significant asymmetrical septal hypertrophy and raised suspicion for hypertrophic cardiomyopathy. Cardiovascular magnetic resonance confirmed the asymmetrical hypertrophy. No myocardial late gadolinium contrast enhancement was seen. However, precontrast T1 mapping revealed a low native myocardial T1 value. This was highly suggestive of Anderson-Fabry disease, which was subsequently proved with very low alpha galactosidase enzyme levels and mutation analysis. The case illustrates clinical usefulness of multimodality imaging and the novel tissue characterization techniques for assessment of left ventricular hypertrophy. © 2016, Wiley Periodicals, Inc.
Screening for Fabry disease in left ventricular hypertrophy: documentation of a novel mutation.
Baptista, Ana; Magalhães, Pedro; Leão, Sílvia; Carvalho, Sofia; Mateus, Pedro; Moreira, Ilídio
2015-08-01
Fabry disease is a lysosomal storage disease caused by enzyme α-galactosidase A deficiency as a result of mutations in the GLA gene. Cardiac involvement is characterized by progressive left ventricular hypertrophy. To estimate the prevalence of Fabry disease in a population with left ventricular hypertrophy. The patients were assessed for the presence of left ventricular hypertrophy defined as a left ventricular mass index ≥ 96 g/m2 for women or ≥ 116 g/m2 for men. Severe aortic stenosis and arterial hypertension with mild left ventricular hypertrophy were exclusion criteria. All patients included were assessed for enzyme α-galactosidase A activity using dry spot testing. Genetic study was performed whenever the enzyme activity was decreased. A total of 47 patients with a mean left ventricular mass index of 141.1 g/m2 (± 28.5; 99.2 to 228.5 g/m2] were included. Most of the patients were females (51.1%). Nine (19.1%) showed decreased α-galactosidase A activity, but only one positive genetic test - [GLA] c.785G>T; p.W262L (exon 5), a mutation not previously described in the literature. This clinical investigation was able to establish the association between the mutation and the clinical presentation. In a population of patients with left ventricular hypertrophy, we documented a Fabry disease prevalence of 2.1%. This novel case was defined in the sequence of a mutation of unknown meaning in the GLA gene with further pathogenicity study. Thus, this study permitted the definition of a novel causal mutation for Fabry disease - [GLA] c.785G>T; p.W262L (exon 5).
Caetano, Francisca; Botelho, Ana; Mota, Paula; Silva, Joana; Leitão Marques, António
2014-03-01
Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by abnormalities of the GLA gene, which encodes the enzyme α-galactosidase A. A deficiency of this enzyme leads to the lysosomal accumulation of glycosphingolipids, which may cause left ventricular hypertrophy that is typically concentric and symmetric. We present the case of a 60-year-old woman with symptoms of dyspnea, atypical chest pain and palpitations, in whom a transthoracic echocardiogram revealed an apical variant of hypertrophic cardiomyopathy. Analysis of specific sarcomeric genetic mutations was negative. The patient underwent a screening protocol for Anderson-Fabry disease, using a dried blood spot test, which was standard at our institution for patients with left ventricular hypertrophy. The enzymatic activity assay revealed reduced α-galactosidase A enzymatic activity. Molecular analysis identified a missense point mutation in the GLA gene (p.R118C). This case report shows that Anderson-Fabry disease may cause an apical form of left ventricular hypertrophy. The diagnosis was only achieved because of systematic screening, which highlights the importance of screening for Anderson-Fabry disease in patients with unexplained left ventricular hypertrophy, including those presenting with more unusual patterns, such as apical variants of left ventricular hypertrophy. This case also supports the idea that the missense mutation R118C is indeed a true pathogenic mutation of Anderson-Fabry disease. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.
Suárez, Carmen; Villar, José; Martel, Nieves; Extremera, Blas Gil; Suliman, Najaty; Campo, Carlos; Castellanos, Victoriano; Liébana, Antonio; Rodilla, Enrique; Nieto, Javier; Velasco, Olga; Ruilope, Luis M
2006-01-04
Left ventricular hypertrophy is an important predictor of cardiovascular risk and its detection contributes to risk stratification. However, echocardiography is not a routine procedure and electrocardiography (ECG) underestimates its prevalence. To evaluate the prevalence of echocardiographic left ventricular hypertrophy in low and medium risk non-treated hypertensive subjects, in order to find out the percentage of them who would be reclassified as high risk patients. Cross-sectional, multicenter study was performed in hospital located hypertension units. An echocardiogram was performed in 197 previously untreated hypertensive patients, > 18 years, classified as having low (61%) or medium (39%) risk, according to the OMS/ISH classification. The presence of left ventricular hypertrophy was considered if left ventricular mass index was > or = 134 or 110 g/m(2) in men and women, respectively (Devereux criteria). A logistic regression analysis was performed to identify factors associated to left ventricular hypertrophy. The prevalence of left ventricular hypertrophy was 23.9% (95% CI:17.9-29.9), 25.6% in men and 22.6% in women. In the low risk group its prevalence was 20.7% and in medium risk group 29.5%. Factors associated to left ventricular hypertrophy were: years since the diagnosis of hypertension, OR:1.1 (95% CI:1.003-1.227); systolic blood pressure, OR:1.08 (95% CI:1.029-1.138); diastolic blood pressure, OR:0.9 (95% CI:0.882-0.991); and family history of cardiovascular disease, OR:4.3 (95% CI:1.52-12.18). These findings underline the importance of performing an echocardiogram in low and high risk untreated hypertensive patients in which treatment would otherwise be delayed for even one year.
Germain, Dominique P; Weidemann, Frank; Abiose, Ademola; Patel, Manesh R; Cizmarik, Marta; Cole, J Alexander; Beitner-Johnson, Dana; Benistan, Karelle; Cabrera, Gustavo; Charrow, Joel; Kantola, Ilkka; Linhart, Ales; Nicholls, Kathy; Niemann, Markus; Scott, C Ronald; Sims, Katherine; Waldek, Stephen; Warnock, David G; Strotmann, Jörg
2013-12-01
The aim of this study was to evaluate the progression of left ventricular hypertrophy in untreated men with Fabry disease and to assess the effects of agalsidase-β (recombinant human α-galactosidase A) on left ventricular hypertrophy. Longitudinal Fabry Registry data were analyzed from 115 men treated with agalsidase-β (1 mg/kg/2 weeks) and 48 untreated men. Measurements included baseline left-ventricular mass and at least one additional left-ventricular mass assessment over ≥ 2 years. Patients were grouped into quartiles, based on left-ventricular mass slopes. Multivariate logistic regression analyses identified factors associated with left ventricular hypertrophy progression. For men in whom treatment was initiated at the age of 18 to <30 years, mean left ventricular mass slope was -3.6 g/year (n = 31) compared with +9.5 g/year in untreated men of that age (n = 15) (P < 0.0001). Untreated men had a 3.4-fold higher risk of having faster increases in left-ventricular mass compared with treated men (odds ratio: 3.43; 95% confidence interval: 1.05-11.22; P = 0.0415). A baseline age of ≥ 40 years was also associated with left--ventricular hypertrophy progression (odds ratio: 5.03; 95% confidence interval: 1.03-24.49; P = 0.0457) compared with men younger than 30 years. Agalsidase-β treatment for ≥2 years may improve or stabilize left-ventricular mass in men with Fabry disease. Further investigations may determine whether early intervention and stabilization of LVM are correlated with clinical outcomes.
Davey, P; Bryant, S; Hart, G
2001-01-01
Left ventricular hypertrophy predisposes to sudden cardiac death (SCD) and studies of human SCD suggest that the antecedent heart rate (HR) is usually < 100 beats min(-1). This is surprising in view of the known association between adrenergic receptor stimulation and SCD which by itself would suggest that it is more likely to occur from high rather than low HR. We therefore hypothesized that there may be electrical or mechanical abnormalities present in myocytes isolated from animals with left ventricular hypertrophy that predispose to SCD at low stimulation frequencies but which may not be present at high HR. Mild left ventricular hypertrophy was induced in guinea-pigs by infra-renal aortic banding. Electrical and mechanical properties of isolated myocytes were studied at different stimulation frequencies between 0.1 and 3 Hz. Action potential duration (APD) is prolonged in hypertrophy at stimulation frequencies < 1 Hz but not at faster rates. Contraction size, time-to-peak contraction (TTPC) and half-relaxation time are greatly enhanced in hypertrophy at all frequencies between 0.1 and 3 Hz. Electrical (50.3 +/- 5.2 ms in hypertrophy and 78.4 +/- 12.1 ms in control, P < 0.03) and mechanical (205 +/- 16 ms for hypertrophy and 266 +/- 24 ms for control cells, P < 0.03) restitution time constants are quicker in hypertrophy. The finding of APD prolongation at low but not at high frequencies is consistent with the finding that SCD arises from low and not high HR. This data supports the role of abnormal repolarization in SCD.
NASA Technical Reports Server (NTRS)
Tagawa, H.; Koide, M.; Sato, H.; Zile, M. R.; Carabello, B. A.; Cooper, G. 4th
1998-01-01
Increased microtubule density causes cardiocyte contractile dysfunction in right ventricular (RV) pressure-overload hypertrophy, and these linked phenotypic and contractile abnormalities persist and progress during the transition to failure. Although more severe in cells from failing than hypertrophied RVs, the mechanical defects are normalized in each case by microtubule depolymerization. To define the role of increased microtubule density in left ventricular (LV) pressure-overload hypertrophy and failure, in a given LV we examined ventricular mechanics, sarcomere mechanics, and free tubulin and microtubule levels in control dogs and in dogs with aortic stenosis both with LV hypertrophy alone and with initially compensated hypertrophy that had progressed to LV muscle failure. In comparing initial values with those at study 8 weeks later, dogs with hypertrophy alone had a very substantial increase in LV mass but preservation of a normal ejection fraction and mean systolic wall stress. Dogs with hypertrophy and associated failure had a substantial but lesser increase in LV mass and a reduction in ejection fraction, as well as a marked increase in mean systolic wall stress. Cardiocyte contractile function was equivalent, and unaffected by microtubule depolymerization, in cells from control LVs and those with compensated hypertrophy. In contrast, cardiocyte contractile function in cells from failing LVs was quite depressed but was normalized by microtubule depolymerization. Microtubules were increased only in failing LVs. These contractile and cytoskeletal changes, when assayed longitudinally in a given dog by biopsy, appeared in failing ventricles only when wall stress began to increase and function began to decrease. Thus, the microtubule-based cardiocyte contractile dysfunction characteristic of pressure-hypertrophied myocardium, originally described in the RV, obtains equally in the LV but is shown here to have a specific association with increased wall stress.
38 CFR 4.97 - Schedule of ratings-respiratory system.
Code of Federal Regulations, 2013 CFR
2013-07-01
... pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by... hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or...; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension...
38 CFR 4.97 - Schedule of ratings-respiratory system.
Code of Federal Regulations, 2012 CFR
2012-07-01
... pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by... hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or...; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension...
38 CFR 4.97 - Schedule of ratings-respiratory system.
Code of Federal Regulations, 2011 CFR
2011-07-01
... pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by... hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or...; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension...
38 CFR 4.97 - Schedule of ratings-respiratory system.
Code of Federal Regulations, 2010 CFR
2010-07-01
... pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by... hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or...; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension...
38 CFR 4.97 - Schedule of ratings-respiratory system.
Code of Federal Regulations, 2014 CFR
2014-07-01
... pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by... hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or...; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension...
Patterns of left ventricular remodeling among patients with essential and secondary hypertension.
Radulescu, Dan; Stoicescu, Laurentiu; Buzdugan, Elena; Donca, Valer
2013-12-01
High blood pressure causes left ventricular hypertrophy, which is a negative prognostic factor among hypertensive patients. To assess left ventricular geometric remodeling patterns in patients with essential hypertension or with hypertension secondary to parenchymal renal disease. We analyzed data from echocardiograms performed in 250 patients with essential hypertension (150 females) and 100 patients with secondary hypertension (60 females). The interventricular septum and the left ventricular posterior wall thickness were measured in the parasternal long-axis. Left ventricular mass was calculated using the Devereaux formula. The most common remodeling type in females and males with essential hypertension were eccentric and concentric left ventricular hypertrophy (cLVH), respectively. Among patients with secondary arterial hypertension, cLVH was most commonly observed in both genders. The prevalence of left ventricular hypertrophy was higher among patients with secondary hypertension. The left ventricular mass index and the relative left ventricular wall thickness were higher in males and also in the secondary hypertension group. Age, blood pressure values and the duration of hypertension, influenced remodeling patterns. We documented a higher prevalence of LVH among patients with secondary hypertension. The type of ventricular remodeling depends on gender, age, type of hypertension, blood pressure values and the duration of hypertension.
Wang, Hegui; Huang, Ting; Wang, Zheng; Ge, Nannan; Ke, Yongsheng
2018-04-28
To observe the changes of rapidly activated delayed rectifier potassium channel (IKr) and slowly activated delayed rectifier potassium channel (IKs) in cardiac hypertrophy and to evaluate the effects of IKr and IKs blocker on the incidence of ventricular arrhythmias in guinea pigs with left ventricular hypertrophy (LVH). Methods: Guinea pigs were divided into a sham operation group and a left ventricular hypertrophy (LVH) group. LVH model was prepared. Whole cell patch-clamp technique was used to record IKr and IKs tail currents in a guinea pig model with LVH. The changes of QTc and the incidence rate of ventricular arrhythmias in LVH guinea pigs were observed by using the IKr and IKs blockers. Results: Compared with cardiac cells in the control group, the interventricular septal thickness at end systole (IVSs), left ventricular posterior wall thickness at end systole (LVPWs), QTc interval and cell capacitance in guinea pigs with LVH were significantly increased (P<0.05); while IKs densities were significantly reduced [+60 mV: (0.36±0.03) pA/pF vs (0.58±0.05) pA/pF, P<0.01]. However, LVH exerted no significant effect on IKr densities. IKr blocker markedly prolonged the QTc interval (P<0.01) and increased the incidence of ventricular arrhythmias in guinea pigs with LVH compared with the control guinea pigs. In contrast, IKs blocker produced modest increase in QTc interval in guinea pigs of control group with no increase in LVH animals. IKs blocker did not induce ventricular arrhythmias incidence in either control or LVH animals. Conclusion: The cardiac hypertrophy-induced arrhythmogenesis is due to the down-regulation of IKs.
Matuszewska, Gabriela; Marek, Bogdan; Kajdaniuk, Dariusz; Przywara-Chowaniec, Brygida; Jarzab, Jerzy; Jarzab, Barbara
2007-01-01
Patients with differentiated thyroid carcinoma have to undergo radical surgical treatment, which includes total thyreoidectomy, radioiodine therapy and a life-time suppressive therapy with L-thyroxine. The aim of this study was a prospective evaluation of left ventricular hypertrophy during L suppressive-thyroxine treatment in patients treated for differentiated thyroid carcinoma. The examined group comprised 50 patients with differentiated thyroid carcinoma, treated by total thyroidectomy and 131I therapy. Echocardiographic measurements were needed for estimation of left ventricular mass and its index, according to recommendations of American Echocardiography Society. During two-years long suppressive therapy we observed a significant rise in left ventricular mass. In woman group left ventricular mass was increased from 168+/-39 g to 204+/-45 g (p<0.001) and in men from 205+/-60 to 320+/-21 g. Likewise, left ventricular mass index was increased in women group from 96+/-18 g/m(2) to 116+/-25 g/m(2) (p<0.001) and in men group from 107+/-37 g/m(2) to 158+/-28 g/m(2). Simultaneous treatment with bisoprolol caused a regression of left myocardial hypertrophy. Already after 6 months of simultaneous treatment with L-thyroxin and bisoprolol, for left ventricular mass was reduced to normal: in woman 165+/-35 g, and in men to 178+/-38 g. Analogous results were obtained left ventricular mass index. After 6 months it was reduced to 94+/-12 g/m(2) in woman and in men to 132+/-32 g/m(2). 1. In differentiated thyroid cancer patients, treated postoperatively with L-thyroxine suppressive therapy, left ventricular hypertrophy is observed already during the first year of suppressive therapy and progresses during the next year of treatment. 2 Addition of a beta-adrenergic antagonist to suppressive doses of L-thyroxine causes a regression of left ventricular hypertrophy, thus, beta-adrenergic antagonists should be administered in this group of patients.
Microtubule Stabilization in Pressure Overload Cardiac Hypertrophy
Sato, Hiroshi; Nagai, Toshio; Kuppuswamy, Dhandapani; Narishige, Takahiro; Koide, Masaaki; Menick, Donald R.; IV, George Cooper
1997-01-01
Increased microtubule density, for which microtubule stabilization is one potential mechanism, causes contractile dysfunction in cardiac hypertrophy. After microtubule assembly, α-tubulin undergoes two, likely sequential, time-dependent posttranslational changes: reversible carboxy-terminal detyrosination (Tyr-tubulin ↔ Glu-tubulin) and then irreversible deglutamination (Glu-tubulin → Δ2-tubulin), such that Glu- and Δ2-tubulin are markers for long-lived, stable microtubules. Therefore, we generated antibodies for Tyr-, Glu-, and Δ2-tubulin and used them for staining of right and left ventricular cardiocytes from control cats and cats with right ventricular hypertrophy. Tyr- tubulin microtubule staining was equal in right and left ventricular cardiocytes of control cats, but Glu-tubulin and Δ2-tubulin staining were insignificant, i.e., the microtubules were labile. However, Glu- and Δ2-tubulin were conspicuous in microtubules of right ventricular cardiocytes from pressure overloaded cats, i.e., the microtubules were stable. This finding was confirmed in terms of increased microtubule drug and cold stability in the hypertrophied cells. In further studies, we found an increase in a microtubule binding protein, microtubule-associated protein 4, on both mRNA and protein levels in pressure-hypertrophied myocardium. Thus, microtubule stabilization, likely facilitated by binding of a microtubule-associated protein, may be a mechanism for the increased microtubule density characteristic of pressure overload cardiac hypertrophy. PMID:9362514
Characteristics of single Ca(2+) channel kinetics in feline hypertrophied ventricular myocytes.
Yang, Xiangjun; Hui, Jie; Jiang, Tingbo; Song, Jianping; Liu, Zhihua; Jiang, Wenping
2002-04-01
To explore the mechanism underlying the prolongation of action potential and delayed inactivation of the L-type Ca(2+) (I(Ca, L)) current in a feline model of left ventricular system hypertension and concomitant hypertrophy. Single Ca(2+) channel properties in myocytes isolated from normal and pressure overloaded cat left ventricles were studied, using patch-clamp techniques. Left ventricular pressure overload was induced by partial ligation of the ascending aorta for 4 - 6 weeks. The amplitude of single Ca(2+) channel current evoked by depolarizing pulses from -40 mV to 0 mV was 1.02 +/- 0.03 pA in normal cells and 1.05 +/- 0.03 pA in hypertrophied cells, and there was no difference in single channel current-voltage relationships between the groups since slope conductance was 26.2 +/- 1.0 pS in normal and hypertrophied cells, respectively. Peak amplitudes of the ensemble-averaged single Ca(2+) channel currents were not different between the two groups of cells. However, the amplitude of this averaged current at the end of the clamp pulse was significantly larger in hypertrophied cells than in normal cells. Open-time histograms revealed that open-time distribution was fitted by a single exponential function in channels of normal cells and by a two exponential function in channels of hypertrophied cells. The number of long-lasting openings was increased in channels of hypertrophied cells, and therefore the calculated mean open time of the channel was significantly longer compared to normal controls. Kinetic changes in the Ca(2+) channel may underlie both hypertrophy-associated delayed inactivation of the Ca(2+) current and, in part, the pressure overload-induced action potential lengthening in this cat model of ventricular left systolic hypertension and hypertrophy.
The 4th Report of the Working Group on ECG diagnosis of Left Ventricular Hypertrophy.
Bacharova, Ljuba; Estes, Harvey E; Schocken, Douglas D; Ugander, Martin; Soliman, Elsayed Z; Hill, Joseph A; Bang, Lia E; Schlegel, Todd T
The 4th Report provides a brief review of publications focused on the electrocardiographic diagnosis of left ventricular hypertrophy published during the period of 2010 to 2016 by the members of the Working Group on ECG diagnosis of Left Ventricular Hypertrophy. The Working Group recommended that ECG research and clinical attention be redirected from the estimation of LVM to the identification of electrical remodeling, to better understanding the sequence of events connecting electrical remodeling to outcomes. The need for a re-definition of terms and for a new paradigm is also stressed. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Tumbur, O.; Safri, Z.; Hassan, R.
2018-03-01
Different types of left ventricular hypertrophy geometry are associated with different risk of cardiovascular disease. The purpose of this study was to determine the role of various ECG voltages of LVH to distinguish the type of LVH geometry. A cross-sectional study from June to November 2015, 100 patients in Adam Malik Hospital Medan. The result of LVH ECG criteria of Sokolow-Lyon was not met then obtained normal left ventricular geometry with 60% sensitivity, 72.22% specificity, and 71% accuracy. The eccentric type of LVH is obtained when the Cornel Voltage is not met; the sensitivity is 25%, specificity 71.88%, and 55% accuracy. Concentric geometric hypertrophy when the RV6/V5> 1 ratio is satisfied, the sensitivity is 55.56%, specificity 56.36%, and 56% accuracy. The RV6/V5>1 ratio was not met, the concentric geometry type of hypertrophy remodeling was determined with a sensitivity of 55.56%, specificity 49.45%, and 50% accuracy. Conclusions, various LVHECG criteria distinguish the type of LVH geometry. Sokolow-Lyon and Cornel Voltage sensitivity and specificity are better than the RV6/V5 ratio.
Chouabe, C; Espinosa, L; Megas, P; Chakir, A; Rougier, O; Freminet, A; Bonvallet, R
1997-01-01
The present paper describes the effect of a simulated hypobaric condition (at the altitude of 4500 m) on morphological characteristics and on some ionic currents in ventricular cells of adult rats. According to current data, chronic high-altitude exposure led to mild right ventricular hypertrophy. Increase in right ventricular weight appeared to be due wholly or partly to an enlargement of myocytes. The whole-cell patch-clamp technique was used and this confirmed, by cell capacitance measurement, that chronic high-altitude exposure induced an increase in the size of the right ventricular cells. Hypertrophied cells showed prolongation of action potential (AP). Four ionic currents, playing a role along with many others in the precise balance of inward and outward currents that control the duration of cardiac AP, were investigated. We report a significant decrease in the transient outward (I(to1)) and in the L-type calcium current (I(Ca,L)) densities while there was no significant difference in the delayed rectifier current (I(K)) or in the inward rectifier current (I(K1)) densities in hypertrophied right ventricular cells compared to control cells. At a given potential the decrease in I(to 1) density was relatively more important than the decrease in I(Ca,L) density. In both cell types, all the currents displayed the same voltage dependence. The inactivation kinetics of I(to 1) and I(Ca,L) or the steady-state activation and inactivation relationships were not significantly modified by chronic high-altitude exposure. We conclude that chronic high-altitude exposure induced true right ventricular myocyte hypertrophy and that the decrease in I(to 1) density might account for the lengthened action potential, or have a partial effect.
Kinnunen, P.; Taskinen, T.; Leppäluoto, J.; Ruskoaho, H.
1990-01-01
1. Ventricular hypertrophy is characterized by stimulation of ventricular synthesis of atrial natriuretic peptide (ANP). To examine the role of ventricular ANP levels in the secretion of ANP into the circulation, atrial and ventricular levels of immunoreactive-ANP (IR-ANP) as well as ANP messenger RNA (mRNA), and the release of IR-ANP from isolated perfused hearts, both before and after atrialectomy, were measured simultaneously in control and minoxidil-treated Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. 2. IR-ANP levels in the ventricles of untreated, 12 month-old SHR with severe ventricular hypertrophy were increased when compared to age-matched WKY rats. Minoxidil treatment for 8 weeks in both strains resulted in a decrease in mean arterial pressure and increases in ventricular weight to body weight ratios, plasma IR-ANP concentrations (in WKY from 133 +/- 20 to 281 +/- 34 pg ml-1, P less than 0.01; in SHR from 184 +/- 38 to 339 +/- 61 pg ml-1, P less than 0.05), and in ventricular IR-ANP contents (in WKY: 53%; in SHR: 41%). A highly significant correlation was found between ventricular IR-ANP content and ventricular weight to body weight ratio (r = 0.59, P less than 0.001, n = 26). 3. When studied in vitro, in isolated perfused heart preparations, the hypertrophied ventricular tissue after atrialectomy secreted more ANP into the perfusate than ventricles of the control hearts; ventricles contributed 28%, 22%, 18% and 15% of the total ANP release to perfusate in the minoxidil-treated SHR, control SHR, minoxidil-treated WKY and control WKY, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2141796
Asymptomatic cardiopulmonary changes caused by adenoid hypertrophy.
Abdel-Aziz, Mosaad
2011-07-01
Adenoid hypertrophy is the most common cause of pediatric upper airway obstruction, and it can lead to cardiopulmonary complications such as pulmonary hypertension, cor pulmonale, and even heart failure. The aim of this study was to detect the asymptomatic cardiopulmonary changes that could happen in children with adenoid hypertrophy.Eighty children with adenoid hypertrophy were included in this study. Chest x-ray was used to assess the cardiothoracic ratio, whereas echocardiography was used for measuring the pulmonary arterial pressures, right ventricular diastolic filling parameters, and right ventricular end-diastolic diameters. All patients underwent adenoidectomy with or without tonsillectomy, and they were subjected again to echocardiographic assessment 6 months after the operation. No patient showed an increase in the cardiothoracic ratio on x-ray. Preoperative echocardiography showed an increase in pulmonary artery pressure (22.7 [SD, 3.8] mm Hg), a decrease in right ventricular diastolic filling parameters (E/A = 1.03 [SD, 0.17]), and an increase in right ventricular end-diastolic diameters (1.89 [SD, 0.19] cm). Postoperatively, pulmonary artery pressure decreased to 17.2 [SD, 2.1] mm Hg, right ventricular diastolic filling (E/A) increased to 1.25 [SD, 0.11], and right ventricular end-diastolic diameters decreased to 1.68 [SD, 0.12] cm. The comparison between preoperative and postoperative results for each individual parameter was statistically significant. Clinically asymptomatic cardiopulmonary changes due to adenoid hypertrophy are not rare. Early diagnosis and treatment of upper airway obstruction can prevent these serious complications. Echocardiographic examination should be recommended for these patients as a part of preoperative preparation to avoid anesthetic complications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Haipeng; Zhang, Xin; Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Qilu Hospital of Shandong University, Jinan
Cardiac hypertrophy is a key pathophysiological component to biomechanical stress, which has been considered to be an independent and predictive risk factor for adverse cardiovascular events. Taxifolin (TAX) is a typical plant flavonoid, which has long been used clinically for treatment of cardiovascular and cerebrovascular diseases. However, very little is known about whether TAX can influence the development of cardiac hypertrophy. In vitro studies, we found that TAX concentration-dependently inhibited angiotensin II (Ang II) induced hypertrophy and protein synthesis in cardiac myocytes. Then we established a mouse model by transverse aortic constriction (TAC) to further confirm our findings. It wasmore » demonstrated that TAX prevented pressure overload induced cardiac hypertrophy in mice, as assessed by ventricular mass/body weight, echocardiographic parameters, myocyte cross-sectional area, and the expression of ANP, BNP and β-MHC. The excess production of reactive oxygen species (ROS) played critical role in the development of cardiac hypertrophy. TAX arrested oxidative stress and decreased the expression of 4-HNE induced by pressure overload. Moreover, TAX negatively modulated TAC-induced phosphorylation of ERK1/2 and JNK1/2. Further studies showed that TAX significantly attenuated left ventricular fibrosis and collagen synthesis through abrogating the phosphorylation of Smad2 and Smad2/3 nuclear translocation. These results demonstrated that TAX could inhibit cardiac hypertrophy and attenuate ventricular fibrosis after pressure overload. These beneficial effects were at least through the inhibition of the excess production of ROS, ERK1/2, JNK1/2 and Smad signaling pathways. Therefore, TAX might be a potential candidate for the treatment of cardiac hypertrophy and fibrosis. - Highlights: • We focus on the protective effect of taxifolin on cardiac remodeling. • Taxifolin inhibited cardiac hypertrophy and attenuated ventricular fibrosis. • Taxifolin suppressed oxidative stress and the excess production of ROS. • Taxifolin blocked ERK1/2, JNK1/2 and Smad signaling pathways. • We reported that taxifolin had the potential to be a candidate for cardiac hypertrophy treatment.« less
Size, shape, and stamina: the impact of left ventricular geometry on exercise capacity.
Lam, Carolyn S P; Grewal, Jasmine; Borlaug, Barry A; Ommen, Steve R; Kane, Garvan C; McCully, Robert B; Pellikka, Patricia A
2010-05-01
Although several studies have examined the cardiac functional determinants of exercise capacity, few have investigated the effects of structural remodeling. The current study evaluated the association between cardiac geometry and exercise capacity. Subjects with ejection fraction > or = 50% and no valvular disease, myocardial ischemia, or arrhythmias were identified from a large prospective exercise echocardiography database. Left ventricular mass index and relative wall thickness were used to classify geometry into normal, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. All of the subjects underwent symptom-limited treadmill exercise according to standard Bruce protocol. Maximal exercise tolerance was measured in metabolic equivalents. Of 366 (60+/-14 years; 57% male) subjects, 166 (45%) had normal geometry, 106 (29%) had concentric remodeling, 40 (11%) had eccentric hypertrophy, and 54 (15%) had concentric hypertrophy. Geometry was related to exercise capacity: in descending order, the maximum achieved metabolic equivalents were 9.9+/-2.8 in normal, 8.9+/-2.6 in concentric remodeling, 8.6+/-3.1 in eccentric hypertrophy, and 8.0+/-2.7 in concentric hypertrophy (all P<0.02 versus normal). Left ventricular mass index and relative wall thickness were negatively correlated with exercise tolerance in metabolic equivalents (r=-0.14; P=0.009 and r=-0.21; P<0.001, respectively). Augmentation of heart rate and ejection fraction with exercise were blunted in concentric hypertrophy compared with normal, even after adjusting for medications. In conclusion, the pattern of ventricular remodeling is related to exercise capacity among low-risk adults. Subjects with concentric hypertrophy display the greatest limitation, and this is related to reduced systolic and chronotropic reserve. Reverse remodeling strategies may prevent or treat functional decline in patients with structural heart disease.
Size, Shape and Stamina: The Impact of Left Ventricular Geometry on Exercise Capacity
Lam, Carolyn S.P.; Grewal, Jasmine; Borlaug, Barry A.; Ommen, Steve R.; Kane, Garvan C.; McCully, Robert B.; Pellikka, Patricia A.
2010-01-01
While several studies have examined the cardiac functional determinants of exercise capacity, few have investigated the effects of structural remodeling. The current study evaluated the association between cardiac geometry and exercise capacity. Subjects with ejection fraction ≥ 50% and no valvular disease, myocardial ischemia or arrhythmias were identified from a large prospective exercise echocardiography database. Left ventricular mass index and relative wall thickness were used to classify geometry into normal, concentric remodeling, eccentric hypertrophy and concentric hypertrophy. All subjects underwent symptom-limited treadmill exercise according to standard Bruce protocol. Maximal exercise tolerance was measured in metabolic equivalents. Of 366 (60±14 years; 57% male) subjects, 166(45%) had normal geometry, 106(29%) had concentric remodeling, 40(11%) had eccentric hypertrophy and 54(15%) had concentric hypertrophy. Geometry was related to exercise capacity: in descending order, the maximum achieved metabolic equivalents was 9.9±2.8 in normal, 8.9±2.6 in concentric remodeling, 8.6±3.1 in eccentric hypertrophy and 8.0±2.7 in concentric hypertrophy (all p<0.02 vs normal). Left ventricular mass index and relative wall thickness were negatively correlated with exercise tolerance in metabolic equivalents (r= -0.14; p=0.009 and r= -0.21; p<0.001, respectively). Augmentation of heart rate and ejection fraction with exercise were blunted in concentric hypertrophy compared to normal, even after adjusting for medications. In conclusion, the pattern of ventricular remodeling is related to exercise capacity among low-risk adults. Subjects with concentric hypertrophy display the greatest limitation and this is related to reduced systolic and chronotropic reserve. Reverse remodeling strategies may prevent or treat functional decline in patients with structural heart disease. PMID:20215563
Mbaye, A; Dodo, B; Ngaïde, A A; Sy, N F; Babaka, K; Mingou, J S; Faye, M; Niang, K; Sarr, S A; Dioum, M; Bodian, M; Ndiaye, M B; Kane, A D; Ndour-Mbaye, M; Diao, M; Diack, B; Kane, M; Diagne-Sow, D; Thiaw, I; Kane, A
2017-09-01
To assess the prevalence of left ventricular hypertrophy according to electrocardiographic and echocardiographic criteria among hypertensive patients living in semi-rural Senegalese area. According to the World Health Organization STEPSwise approach, we conducted, in November 2012, a cross-sectional and exhaustive study in the population aged at least 35 years old and living for at least six months in the semi-rural area of Guéoul. We researched electrocardiographic and echocardiographic left ventricular hypertrophy in hypertensive subjects. Data were analyzed with SPSS 18.0 software version. The significance level was agreed for a value of P<0.05. We examined 1411 subjects aged on average of 48.5±12.7 years. In total, 654 subjects were hypertensive and screening of left ventricular hypertrophy (LVH) was effective in 515 of them. According to Sokolow-Lyon index, 86 subjects (16.7%) presented electrocardiographic LVH, more frequently in men (P=0.002). According to Cornell index and Cornell product, LVH was founded respectively in 66 (12.8%) and 52 subjects (10.1%), more frequently in female (P=0.0001; P=0.004). It was more common in grade 3 of hypertension however criteria. In echocardiography, prevalence of LVH was 2.2% (13 cases) according to the left ventricular mass, 9.3% (48 cases) according to the left ventricular mass indexed to body surface area and 8.2% (42 cases) according to the left ventricular mass indexed to height 2.7 . LVH was significantly correlated with the electrocardiographic LVH according to Sokolow-Lyon index (P<0.0001) and the grade 3 of hypertension (P=0.003). Although rare in hypertensive Senegalese living in semi-rural area, left ventricular hypertrophy is correlated with severity of grade of hypertension. Screening by electrocardiogram will allow better follow-up of these hypertensive subjects. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
[Blood pressure variability and left ventricular hypertrophy in arterial hypertension].
Amodeo, C; Martins, S M; Silva Júnior, O; Barros, L M; Batlouni, M; Sousa, J E
1993-05-01
To evaluate the left ventricular hypertrophy correlation with blood pressure variability during day and night time as well as throughout the 24h period. Fifteen patients with mild to moderate essential hypertension underwent to bi-dimensional echocardiographic study and to 24h ambulatory blood pressure monitorization. Left ventricular mass was calculated according to previous validated formulas. The standard deviation of the mean blood pressures during day-time, night-time and 24h period was taken as blood pressure variability indices. The mean age of the group was 42 years old; 9 patients were male and all were white. This study showed that only the systolic and diastolic blood pressure variability during the 24h period correlated significantly with left ventricular mass, (r = 0.53 and p < 0.05; r = 0.58 and p < 0.05 respectively). There was no significant correlation of the day-time and night-time pressures variability with left ventricular mass. The systolic and diastolic blood pressure variability during the 24h period may be one of the many determinants of left ventricular hypertrophy in patients with mild to moderate hypertension.
"Reversibility of Cardiovascular Injury With CPAP Use: Mechanisms Involved"
2015-09-29
Sleep Apnea, Obstructive; Hypoxia; Hypercapnia; Sleep Disorders; Obesity; Hypertension; Coronary Artery Vasospasm; Right Ventricular Overload; Left Ventricular Function Systolic Dysfunction; Ventricular Hypertrophy
Alam, Md. Ashraful; Kauter, Kathleen; Brown, Lindsay
2013-01-01
Obesity, insulin resistance, hypertension and fatty liver, together termed metabolic syndrome, are key risk factors for cardiovascular disease. Chronic feeding of a diet high in saturated fats and simple sugars, such as fructose and glucose, induces these changes in rats. Naturally occurring compounds could be a cost-effective intervention to reverse these changes. Flavonoids are ubiquitous secondary plant metabolites; naringin gives the bitter taste to grapefruit. This study has evaluated the effect of naringin on diet-induced obesity and cardiovascular dysfunction in high carbohydrate, high fat-fed rats. These rats developed increased body weight, glucose intolerance, increased plasma lipid concentrations, hypertension, left ventricular hypertrophy and fibrosis, liver inflammation and steatosis with compromised mitochondrial respiratory chain activity. Dietary supplementation with naringin (approximately 100 mg/kg/day) improved glucose intolerance and liver mitochondrial dysfunction, lowered plasma lipid concentrations and improved the structure and function of the heart and liver without decreasing total body weight. Naringin normalised systolic blood pressure and improved vascular dysfunction and ventricular diastolic dysfunction in high carbohydrate, high fat-fed rats. These beneficial effects of naringin may be mediated by reduced inflammatory cell infiltration, reduced oxidative stress, lowered plasma lipid concentrations and improved liver mitochondrial function in rats. PMID:23446977
Sanchez-Soria, Pablo; Broka, Derrick; Monks, Sarah L; Camenisch, Todd D
2012-04-01
Cardiovascular disease is the leading cause of death in the United States and worldwide. High incidence of cardiovascular diseases has been linked to populations with elevated arsenic content in their drinking water. Although this correlation has been established in many epidemiological studies, a lack of experimental models to study mechanisms of arsenic-related cardiovascular pathogenesis has limited our understanding of how arsenic exposure predisposes for development of hypertension and increased cardiovascular mortality. Our studies show that mice chronically exposed to drinking water containing 100 parts per billion (ppb) sodium arsenite for 22 weeks show an increase in both systolic and diastolic blood pressure. Echocardiographic analyses as well as histological assessment show concentric left ventricular hypertrophy, a primary cardiac manifestation of chronic hypertension. Live imaging by echocardiography shows a 43% increase in left ventricular mass in arsenic-treated animals. Relative wall thickness (RWT) was calculated showing that all the arsenic-exposed animals show an RWT greater than 0.45, indicating concentric hypertrophy. Importantly, left ventricular hypertrophy, although often associated with chronic hypertension, is an independent risk factor for cardiovascular-related mortalities. These results suggest that chronic low-level arsenite exposure promotes the development of hypertension and the comorbidity of concentric hypertrophy.
Aje, Akinyemi; Adebiyi, Adewole A; Oladapo, Olulola O; Dada, Adekola; Ogah, Okechukwu S; Ojji, Dike B; Falase, Ayodele O
2006-01-01
Background Hypertension is a global problem and it is prevalent in Nigeria. Left ventricular hypertrophy is a major complication of hypertension with risk of sudden death and arrhythmias among others. Abnormal left ventricular geometric patterns also increase the burden of morbidity and mortality. It is therefore important to know the different left ventricular geometric patterns in Nigerian hypertensives because of their prognostic significance. Methods One hundred (100) newly presenting hypertensives (53 males and 47 females) and 100 controls (53 males and 47 females) were recruited for the study. All were subjected to clinical evaluation and full echocardiographic examination was performed according to the ASE recommendation. The relative wall thickness and the presence or absence of echocardiographic left ventricular hypertrophy were used to determine the various geometric patterns Results The mean age of the hypertensive subjects was 56.06 (± 7.68) years while that of the control subjects was 56.10 (± 7.68) years. There was no significant difference in the mean ages of the two groups. In the hypertensive subjects 28% had normal geometry, 26% had concentric remodeling, 28% had concentric hypertrophy and 18% had eccentric hypertrophy. In the control group, 86% had normal geometry, 11% had concentric remodeling, 3% had eccentric hypertrophy and none had concentric hypertrophy. There was statistical significance when the geometric patterns of the hypertensive and controls were compared (χ2 = 74.30, p value < 0.0001). Conclusion The study showed that only 28% of the hypertensive subjects had normal LV geometric pattern while 86% of the normal subjects had normal geometry. There is need for longitudinal studies in order to prognosticate the various geometric patterns. PMID:16426452
Right Ventricular Dysfunction in Chronic Lung Disease
Kolb, Todd M.; Hassoun, Paul M.
2012-01-01
Right ventricular dysfunction arises in chronic lung disease when chronic hypoxemia and disruption of pulmonary vascular beds contribute to increase ventricular afterload, and is generally defined by hypertrophy with preserved myocardial contractility and cardiac output. Although the exact prevalence is unknown, right ventricular hypertrophy appears to be a common complication of chronic lung disease, and more frequently complicates advanced lung disease. Right ventricular failure is rare, except during acute exacerbations of chronic lung disease or when multiple co-morbidities are present. Treatment is targeted at correcting hypoxia and improving pulmonary gas exchange and mechanics. There are presently no convincing data to support the use of pulmonary hypertension-specific therapies in patients with right ventricular dysfunction secondary to chronic lung disease. PMID:22548815
Dynamic right ventricular outflow tract (infundibular) stenosis and pectus excavatum in a dog
Fournier, Tanya E.
2008-01-01
This is the first published report of a dog with dynamic right ventricular outflow tract (infundibular) stenosis, right ventricular hypertrophy, and pectus excavatum. A juvenile dog presented with a grade V/VI left base systolic heart murmur, tachycardia, and pectus excavatum. Diagnosis of the aforementioned conditions was based on radiography, electrocardiography, and echocardiography. At 9 1/2 wk of age the heart murmur was no longer audible and the right ventricular stenosis and hypertrophy had dissipated and regressed, respectively. Resolution may be associated with growth of the dog. A good prognosis is foreseen. PMID:18512460
Deva, Djeven Parameshvara; Hanneman, Kate; Li, Qin; Ng, Ming Yen; Wasim, Syed; Morel, Chantal; Iwanochko, Robert M; Thavendiranathan, Paaladinesh; Crean, Andrew Michael
2016-03-31
Although it is known that Anderson-Fabry Disease (AFD) can mimic the morphologic manifestations of hypertrophic cardiomyopathy (HCM) on echocardiography, there is a lack of cardiovascular magnetic resonance (CMR) literature on this. There is limited information in the published literature on the distribution of myocardial fibrosis in patients with AFD, with scar reported principally in the basal inferolateral midwall. All patients with confirmed AFD undergoing CMR at our center were included. Left ventricular (LV) volumes, wall thicknesses and scar were analyzed offline. Patients were categorized into 4 groups: (1) no wall thickening; (2) concentric hypertrophy; (3) asymmetric septal hypertrophy (ASH); and (4) apical hypertrophy. Charts were reviewed for clinical information. Thirty-nine patients were included (20 males [51%], median age 45.2 years [range 22.3-64.4]). Almost half (17/39) had concentric wall thickening. Almost half (17/39) had pathologic LV scar; three quarters of these (13/17) had typical inferolateral midwall scar. A quarter (9/39) had both concentric wall thickening and typical inferolateral scar. A subgroup with ASH and apical hypertrophy (n = 5) had greater maximum wall thickness, total LV scar, apical scar and mid-ventricular scar than those with concentric hypertrophy (n = 17, p < 0.05). Patients with elevated LVMI had more overall arrhythmia (p = 0.007) more ventricular arrhythmia (p = 0.007) and sustained ventricular tachycardia (p = 0.008). Concentric thickening and inferolateral mid-myocardial scar are the most common manifestations of AFD, but the spectrum includes cases morphologically identical to apical and ASH subtypes of HCM and these have more apical and mid-ventricular LV scar. Significant LVH is associated with ventricular arrhythmia.
Left ventricular hypertrophy: virtuous intentions, malign consequences.
Pokharel, Saraswati; Sharma, Umesh C; Pinto, Yigal M
2003-06-01
Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there are structural changes in myofilaments, disorganization of the cytoskeletal framework and increased collagen synthesis. LVH is associated with progressive left ventricular remodeling that culminates to heart failure. The modern treatment of left ventricular hypertrophy is now largely based on the hypothesis that neuroendocrine activation is important in the progression of the disease and inhibition of neurohormones is likely to have long-term benefit with regard to morbidity and mortality. Drugs specifically designed to unload the left ventricle, such as diuretics and vasodilators, appears to be less effective in reducing LV mass and improving prognosis. Thus, the evolution of treatment for LVH itself has provided much enlightenment for our understanding of the fundamental biology of the disorder.
Seeman, Tomáš; Hradský, Ondřej; Gilík, Jiří
2016-08-01
The aim of our study was to investigate whether nocturnal blood pressure (BP) dip is associated with increased left ventricular mass index and hypertrophy in children with hypertension (HT). We retrospectively reviewed data from all children with confirmed ambulatory HT in our center and performed ambulatory blood pressure monitoring (ABPM) and echocardiography at the same time. Left ventricular hypertrophy (LVH) was defined as left ventricular mass index (LVMI) ≥95th centile. Non-dipping phenomenon was defined as nocturnal BP dip <10 %. A total of 114 ABPM studies were included, the median age of children was 15.3 years (3.8-18.9), 80 children had renoparenchymal HT without end-stage renal failure, 34 had primary HT, and 27 studies were done on untreated children and 87 on treated children. Non-dipping phenomenon was present in 63 (55 %) studies (non-dippers). The LVMI adjusted for age was not significantly different between non-dippers and dippers (0.87 ± 0.03 vs. 0.81 ± 0.02, p = 0.13). Left ventricular hypertrophy was not significantly higher in non-dippers than in dippers (20 vs. 9 %, p = 0.12). Hypertensive children without end-stage renal failure with non-dipping phenomenon do not have increased prevalence of LVH or higher LVMI adjusted for age than hypertensive children with preserved nocturnal BP dip. • Adult and pediatric hypertensive patients with end-stage renal failure have often nocturnal blood pressure non-dipping phenomenon. • Non-dipping phenomenon is in patients with end-stage renal failure associated with increased prevalence of left ventricular hypertrophy. What is New: • Pediatric hypertensive patients without end-stage renal failure with blood pressure non-dipping phenomenon do not have increased prevalence of left ventricular hypertrophy.
Ha, Le Dung; Elbadawi, Ayman; Froelicher, Victor F
2018-01-01
Numerous methods have been proposed for diagnosing left ventricular hypertrophy using the electrocardiogram. They have limited sensitivity for recognizing pathological hypertrophy, at least in part due to their inability to distinguish pathological from physiological hypertrophy. Our objective is to compare the major electrocardiogram-left ventricular hypertrophy criteria using cardiovascular mortality as a surrogate for pathological hypertrophy. This study was a retrospective analysis of 16,253 veterans < 56 years of age seen at a large Veterans Affairs Medical Center from 1987 to 1999 and followed a median of 17.8 years for cardiovascular mortality. Receiver operating characteristics and Cox hazard survival techniques were applied. Of the 16,253 veterans included in our target population, the mean age was 43 years, 8.6% were female, 33.5% met criteria for electrocardiogram-left ventricular hypertrophy, and there were 744 cardiovascular deaths (annual cardiovascular mortality 0.25%). Receiver operating characteristic analysis demonstrated that the greatest area under the curve (AUC) for classification of cardiovascular death was obtained using the Romhilt-Estes score (0.63; 95% confidence interval, 0.61-0.65). Most of the voltage-only criteria had nondiagnostic area under the curves, with the Cornell being the best at 0.59 (95% confidence interval, 0.57-0.62). When the components of the Romhilt-Estes score were examined using step-wise Wald analysis, the voltage criteria dropped from the model. The Romhilt-Estes score ≥ 4, the Cornell, and the Peguero had the highest association with cardiovascular mortality (adjusted hazard ratios 2.2, 2.0, and 2.1, consecutively). None of the electrocardiogram leads with voltage criteria exhibited sufficient classification power for clinical use. Copyright © 2018 Elsevier Inc. All rights reserved.
Sevilla, María A; Voces, Felipe; Carrón, Rosalía; Guerrero, Estela I; Ardanaz, Noelia; San Román, Luis; Arévalo, Miguel A; Montero, María J
2004-07-02
Our objective was to examine the effect of chronic treatment with amlodipine on blood pressure, left ventricular hypertrophy, and fibrosis in spontaneously hypertensive rats and the persistence of such an effect after drug withdrawal. We investigated the effects of treatment with 2, 8 and 20 mg/kg/day of amlodipine given orally for six months and at three months after drug withdrawal. Systolic blood pressure was measured using the tail-cuff method. At the end of the study period, the heart was excised, the left ventricle was isolated, and the left ventricle weight/body weight ratio was calculated as a left ventricular hypertrophy index. Fibrosis, expressed as collagen volume fraction, was evaluated using an automated image-analysis system on sections stained with Sirius red. Age-matched untreated Wistar-Kyoto and SHR were used as normotensive and hypertensive controls, respectively. Systolic blood pressure was reduced in the treated SHR in a dose-dependent way and after amlodipine withdrawal it increased progressively, without reaching the values of the hypertensive controls. Cardiac hypertrophy was reduced by 8 and 20 mg/kg/day amlodipine, but when treatment was withdrawn only the group treated with 8 mg/kg/day maintained significant differences versus the hypertensive controls. All three doses of amlodipine reduced cardiac fibrosis and this regression persisted with the two highest doses after three months without treatment. We concluded that antihypertensive treatment with amlodipine is accompanied by a reduction in left ventricular hypertrophy and regression in collagen deposition. Treatment was more effective in preventing fibrosis than in preventing ventricular hypertrophy after drug withdrawal. Copyright 2004 Elsevier Inc.
Semelka, R C; Tomei, E; Wagner, S; Mayo, J; Caputo, G; O'Sullivan, M; Parmley, W W; Chatterjee, K; Wolfe, C; Higgins, C B
1990-06-01
The validity of geometric formulas to derive mass and volumes in the morphologically abnormal left ventricle is problematic. Imaging techniques that are tomographic and therefore inherently three-dimensional should be more reliable and reproducible between studies in such ventricles. Determination of reproducibility between studies is essential to define the limits of an imaging technique for evaluating the response to therapy. Sequential cine magnetic resonance (MR) studies were performed on patients with dilated cardiomyopathy (n = 11) and left ventricular hypertrophy (n = 8) within a short interval in order to assess interstudy reproducibility. Left ventricular mass, volumes, ejection fraction, and end-systolic wall stress were determined by two independent observers. Between studies, left ventricular mass was highly reproducible for hypertrophied and dilated ventricles, with percent variability less than 6%. Ejection fraction and end-diastolic volume showed close reproducibility between studies, with percent variability less than 5% End-systolic volume varied by 4.3% and 4.5% in dilated cardiomyopathy and 8.4% and 7.2% in left ventricular hypertrophy for the two observers. End-systolic wall stress, which is derived from multiple measurements, varied the greatest, with percent variability of 17.2% and 15.7% in dilated cardiomyopathy and 14.8% and 13% in left ventricular hypertrophy, respectively. The results of this study demonstrate that mass, volume, and functional measurements are reproducible in morphologically abnormal ventricles.
Levosimendan Prevents Pressure-Overload-induced Right Ventricular Failure.
Hillgaard, Thomas Krarup; Andersen, Asger; Andersen, Stine; Vildbrad, Mads D; Ringgaard, Steffen; Nielsen, Jan M; Nielsen-Kudsk, Jens E
2016-04-01
We investigated if chronic levosimendan treatment can prevent and revert pressure-overload-induced right ventricular hypertrophy and failure in rats. Right ventricular hypertrophy and failure was induced in Wistar rats by pulmonary trunk banding (PTB). The PTB rats were treated with levosimendan (3 mg·kg·d) 3 days before surgery [n = 10, prevention (PREV)], 3 weeks after surgery [n = 10, reversal (REV)] or vehicle (n = 10, VEH). Sham-operated rats received vehicle (n = 16, SHAM). Right ventricular function was evaluated 7 weeks after surgery by echocardiography, magnetic resonance imaging, pressure-volume relations, gross anatomy, and histology. PTB induced right ventricular hypertrophy and compensated heart failure evident by reduced cardiac index (CI) without extra cardiac signs of heart failure. Levosimendan treatment prevented deterioration of right ventricular function measured by CI and right ventricular ejection fraction (RVEF) (CI: VEH vs. PREV 281 ± 17 vs. 362 ± 34 mL·min·kg, P ≤ 0.05, RVEF: VEH vs. PREV 57 ± 2% vs. 68 ± 3%, P ≤ 0.01) to values similar to SHAM (CI: 345 ± 21 mL·min·kg, RVEF: 71 ± 2%). RV contractility was improved in the REV group measured by preload recruitable stroke work (VEH vs. REV 39 ± 3 vs. 66 ± 10 mmHg P ≤ 0.05). Chronic treatment with levosimendan prevents the development of right ventricular failure and improves contractility in established pressure-overload-induced right ventricular failure.
El Saiedi, Sonia A; Mira, Marwa F; Sharaf, Sahar A; Al Musaddar, Maysoun M; El Kaffas, Rania M H; AbdelMassih, Antoine F; Barsoum, Ihab H Y
2018-01-01
Obesity increases the risk for various cardiovascular problems. Increase in body mass index is often an independent risk factor for the development of elevated blood pressure and clustering of various cardiovascular risk factors. To determine early markers of left ventricular affection in obese patients before the appearance of left ventricular hypertrophy. In this cross-sectional study, we evaluated 42 obese patients and 30 healthy controls. Their ages ranged from 6 to 19 years. Studied children were subjected to anthropometric, lipid profile, and serum Troponin I level measurements. Echocardiographic evaluation performed to assess the left ventricle included left ventricular dimension measurement using motion-mode echocardiography, based on which patients with left ventricular hypertrophy (10 patients) were eliminated, as well as conventional and tissue Doppler imaging. Tissue Doppler findings in the study groups showed that the ratio of transmitral early diastolic filling velocity to septal peak early diastolic myocardial velocity (E/e') was significantly higher in cases compared with controls [6.9±1.4 versus 9.0±1.6, p (Pearson's coefficient)=0.001, respectively]. The level of cardiac troponin I was significantly higher in cases compared with controls [0.14±0.39 ng/ml versus 0.01±0.01 ng/ml, p (Pearson's coefficient)=0.047, respectively] and there was a significant correlation between troponin I and transmitral early diastolic filling velocity to septal peak early diastolic myocardial velocity ratio (E/e') [R (correlation coefficient)=0.6]. Tissue Doppler Imaging and Troponin I evaluation proved useful tools to detect early affection of the left ventricle in obese patients even in the absence of left ventricular hypertrophy.
Large Lipomatous Hypertrophy of the Interventricular Septum
Ak, Koray; Isbir, Selim; Kepez, Alper; Turkoz, Kemal; Elci, Emre; Arsan, Sinan
2014-01-01
We present the case of a 58-year-old woman who had large lipomatous hypertrophy of the interventricular septum, a condition that is reported very infrequently. Preoperative cardiac magnetic resonance images revealed an inhomogeneous, infiltrating mass that was suppressed in fat-suppression mode. The extensive mass was causing right ventricular dysfunction, so we excised it through a right ventricular approach. The findings on histologic analysis of the mass were consistent with lipomatous hypertrophy. The patient died of septic shock on the 28th postoperative day. In addition to the patient's case, we discuss the characteristics and diagnosis of this rare entity. PMID:24808791
Zhang, Huijie; Zhang, Tao; Li, Shengxu; Guo, Yajun; Shen, Wei; Fernandez, Camilo; Harville, Emily; Bazzano, Lydia A; Urbina, Elaine M; He, Jiang; Chen, Wei
2017-05-12
Childhood adiposity is associated with cardiac structure in later life, but little is known regarding to what extent childhood body weight affects adult left ventricular geometric patterns through adult body size and blood pressure (BP). Determine quantitatively the mediation effect of adult body weight and BP on the association of childhood body mass index (BMI) with adult left ventricular (LV) hypertrophy. This longitudinal study consisted of 710 adults, aged 26 to 48 years, who had been examined for BMI and BP measured ≥4× during childhood and ≥2× during adulthood, with a mean follow-up period of 28.0 years. After adjusting for age, race, and sex, adult BMI had a significant mediation effect (76.4%; P <0.01) on the childhood BMI-adult LV mass index association. The mediation effects of adult systolic BP (15.2%), long-term burden (12.1%), and increasing trends of systolic BP (7.9%) were all significant ( P <0.01). Furthermore, these mediators also had significant mediation effects on the association of childhood BMI with adult LV hypertrophy, eccentric hypertrophy, and concentric hypertrophy. Importantly, the mediation effects of adult BMI were all significantly stronger than those of adult systolic BP on LV mass index, LV hypertrophy, and LV remodeling patterns ( P <0.01). Additionally, the mediation effect of systolic BP on concentric hypertrophy was significantly stronger than that on eccentric hypertrophy ( P <0.01). These findings suggest that increased childhood BMI has long-term adverse impact on subclinical changes in adult cardiac structure, and early life excessive body weight and adult LV hypertrophy are linked through later life excessive body weight and elevated BP. © 2017 American Heart Association, Inc.
Kulshrestha, P; Das, B; Iyer, K S; Sampathkumar, A; Sharma, M L; Rao, I M; Kaul, U; Srivastava, S; Bhatia, M L; Venugopal, P
1989-04-01
Seventy-eight patients undergoing mitral valve surgery with or without replacement of the aortic valve also underwent procedures on the tricuspid valve over a period of 10 years. All patients were in functional class III or IV preoperatively. The procedures were performed in all patients with organic disease of the tricuspid valve (N = 44) and in those with moderate or severe functional tricuspid valvar regurgitation (N = 34). Seventy-one patients underwent DeVega's annuloplasty with or without commissurotomy. The overall mortality was 11.5%. 65 long-term survivors were followed up for a period of 6 months to 10 years (mean 5.3 years). Sixty-three patients were in functional class I or II at the last follow-up. Six patients had clinical evidence of mild to moderate tricuspid regurgitation. Regression of cardiomegaly (as judged by the chest radiograph and right ventricular hypertrophy seen in the electrocardiogram) was evident in most cases. Fifty-one of 54 patients evaluated by cross-sectional echocardiography were reported to have a functionally normal tricuspid valve. Doppler echocardiography in 28 patients showed no significant tricuspid regurgitation or stenosis in 26 patients. Eleven consecutive patients undergoing DeVega's annuloplasty were studied prospectively with pre- and postoperative Doppler echocardiography. Good correlation existed between right ventricular systolic pressures predicted by Doppler with those obtained preoperatively at cardiac catheterization. Postoperative Doppler echocardiography in these 11 patients showed complete restoration of competence of the tricuspid valve as well as normalisation of the right ventricular systolic pressure in 10 patients.
Cardiac structure and function in relation to cardiovascular risk factors in Chinese
2012-01-01
Background Cardiac structure and function are well-studied in Western countries. However, epidemiological data is still scarce in China. Methods Our study was conducted in the framework of cardiovascular health examinations for the current and retired employees of a factory and their family members. According to the American Society of Echocardiography recommendations, we performed echocardiography to evaluate cardiac structure and function, including left atrial volume, left ventricular hypertrophy and diastolic dysfunction. Results The 843 participants (43.0 years) included 288 (34.2%) women, and 191 (22.7%) hypertensive patients, of whom 82 (42.9%) took antihypertensive drugs. The prevalence of left atrial enlargement, left ventricular hypertrophy and concentric remodeling was 2.4%, 5.0% and 12.7%, respectively. The prevalence of mild and moderate-to-severe left ventricular diastolic dysfunction was 14.2% and 3.3%, respectively. The prevalence of these cardiac abnormalities significantly (P ≤ 0.002) increased with age, except for the moderate-to-severe left ventricular diastolic dysfunction. After adjustment for age, gender, body height and body weight, left atrial enlargement was associated with plasma glucose (P = 0.009), and left ventricular hypertrophy and diastolic dysfunction were significantly associated with systolic and diastolic blood pressure (P ≤ 0.03), respectively. Conclusions The prevalence of cardiac structural and functional abnormalities increased with age in this Chinese population. Current drinking and plasma glucose had an impact on left atrial enlargement, whereas systolic and diastolic blood pressures were major correlates for left ventricular hypertrophy and diastolic dysfunction, respectively. PMID:23035836
Li, Tan; Chen, Shuang; Guo, Xiaofan; Yang, Jun; Sun, Yingxian
2017-07-27
The aim of this study was to assess the impact of hypertension with or without diabetes on left ventricular (LV) remodeling in rural Chinese population. A total of 10,270 participants were classified into control group, hypertension without diabetes (HT) group, and hypertension with diabetes (HT + DM) group. We compared clinical characteristics and echocardiographic parameters, and used multivariable logistic regression analysis to assess the associations of interest. HT + DM group had higher interventricular septal thickness (IVSd), posterior wall thickness (PWTd), left ventricular mass (LVM), LVM index (LVMI), relative wall thickness (RWT), left atrial diameter (LAD), A wave and lower E wave than HT group (all P < 0.05). The prevalence rates of left ventricular hypertrophy (LVH) and abnormal geometry were statistically different among three groups (P < 0.001) and eccentric hypertrophy was the highest proportion of geometry abnormality. Logistic regression analysis suggested that subjects in HT and HT + DM groups had odds ratio (OR) values of 2.81, 4.41, 2.24 and 3.94, 7.20, 2.38 for LVH, concentric hypertrophy and eccentric hypertrophy in the total population, respectively, compared to control group. When compared with HT group, those in HT + DM group had approximately 1.40-, 1.61- and 1.38-, 1.71-fold increased risk for LVH and concentric hypertrophy in the total and female population separately, but no association of HT + DM with LVH and abnormal geometrical patterns was found in men. This study demonstrated that, to varying degrees, hypertension was associated with LV remodeling in rural Chinese population, and this risk association was obviously increased for LVH and concentric hypertrophy when accompanied by diabetes, especially for women.
BET Acetyl-Lysine Binding Proteins Control Pathological Cardiac Hypertrophy
Spiltoir, Jessica I.; Stratton, Matthew S.; Cavasin, Maria A.; Demos-Davies, Kim; Reid, Brian G.; Qi, Jun; Bradner, James E.; McKinsey, Timothy A.
2014-01-01
Cardiac hypertrophy is an independent predictor of adverse outcomes in patients with heart failure, and thus represents an attractive target for novel therapeutic intervention. JQ1, a small molecule inhibitor of bromodomain and extraterminal (BET) acetyl-lysine reader proteins, was identified in a high throughput screen designed to discover novel small molecule regulators of cardiomyocyte hypertrophy. JQ1 dose-dependently blocked agonist-dependent hypertrophy of cultured neonatal rat ventricular myocytes (NRVMs) and reversed the prototypical gene program associated with pathological cardiac hypertrophy. JQ1 also blocked left ventricular hypertrophy (LVH) and improved cardiac function in adult mice subjected to transverse aortic constriction (TAC). The BET family consists of BRD2, BRD3, BRD4 and BRDT. BRD4 protein expression was increased during cardiac hypertrophy, and hypertrophic stimuli promoted recruitment of BRD4 to the transcriptional start site (TSS) of the gene encoding atrial natriuretic factor (ANF). Binding of BRD4 to the ANF TSS was associated with increased phosphorylation of local RNA polymerase II. These findings define a novel function for BET proteins as signal-responsive regulators of cardiac hypertrophy, and suggest that small molecule inhibitors of these epigenetic reader proteins have potential as therapeutics for heart failure. PMID:23939492
Common presentation of rare diseases: Left ventricular hypertrophy and diastolic dysfunction.
Linhart, Ales; Cecchi, Franco
2018-04-15
Left ventricular hypertrophy may be a consequence of a hemodynamic overload or a manifestation of several diseases affecting different structural and functional proteins of cardiomyocytes. Among these, sarcomeric hypertrophic cardiomyopathy (HCM) represents the most frequent cause. In addition, several metabolic diseases lead to myocardial thickening, either due to intracellular storage (glycogen storage and lysosomal diseases), extracellular deposition (TTR and AL amyloidosis) or due to abnormal energy metabolism (mitochondrial diseases). The recognition of these rare causes of myocardial hypertrophy is important for family screening strategies, risk assessment, and treatment. Moreover, as there are specific therapies for some forms of HCM including enzyme substitution and chaperone therapies and specific treatments for TTR amyloidosis, a differential diagnosis should be sought in all patients with unexplained left ventricular hypertrophy. Diastolic dysfunction is a key feature of HCM and its phenocopies. Its assessment is complex and requires evaluation of several functional parameters and structural changes. Severe diastolic dysfunction carries a negative prognostic implication and its value in differential diagnosis is limited. Copyright © 2018 Elsevier B.V. All rights reserved.
Garg, Sonia; de Lemos, James A; Matulevicius, Susan A; Ayers, Colby; Pandey, Ambarish; Neeland, Ian J; Berry, Jarett D; McColl, Roderick; Maroules, Christopher; Peshock, Ronald M; Drazner, Mark H
2017-08-01
In the conventional paradigm of the progression of left ventricular hypertrophy, a thick-walled left ventricle (LV) ultimately transitions to a dilated cardiomyopathy. There are scant data in humans demonstrating whether this transition occurs commonly without an interval myocardial infarction. Participants (n=1282) from the Dallas Heart Study underwent serial cardiac magnetic resonance ≈7 years apart. Those with interval cardiovascular events and a dilated LV (increased LV end-diastolic volume [EDV] indexed to body surface area) at baseline were excluded. Multivariable linear regression models tested the association of concentric hypertrophy (increased LV mass and LV mass/volume 0.67 ) with change in LVEDV. The study cohort had a median age of 44 years, 57% women, 43% black, and 11% (n=142) baseline concentric hypertrophy. The change in LVEDV in those with versus without concentric hypertrophy was 1 mL (-9 to 12) versus -2 mL (-11 to 7), respectively, P <0.01. In multivariable linear regression models, concentric hypertrophy was associated with larger follow-up LVEDV ( P ≤0.01). The progression to a dilated LV was uncommon (2%, n=25). In the absence of interval myocardial infarction, concentric hypertrophy was associated with a small, but significantly greater, increase in LVEDV after 7-year follow-up. However, the degree of LV enlargement was minimal, and few participants developed a dilated LV. These data suggest that if concentric hypertrophy does progress to a dilated cardiomyopathy, such a transition would occur over a much longer timeframe (eg, decades) and perhaps less common than previously thought. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00344903. © 2017 American Heart Association, Inc.
Markandeya, Yogananda S.; Phelan, Laura J.; Woon, Marites T.; Keefe, Alexis M.; Reynolds, Courtney R.; August, Benjamin K.; Hacker, Timothy A.; Roth, David M.; Patel, Hemal H.; Balijepalli, Ravi C.
2015-01-01
Pathological cardiac hypertrophy is characterized by subcellular remodeling of the ventricular myocyte with a reduction in the scaffolding protein caveolin-3 (Cav-3), altered Ca2+ cycling, increased protein kinase C expression, and hyperactivation of calcineurin/nuclear factor of activated T cell (NFAT) signaling. However, the precise role of Cav-3 in the regulation of local Ca2+ signaling in pathological cardiac hypertrophy is unclear. We used cardiac-specific Cav-3-overexpressing mice and in vivo and in vitro cardiac hypertrophy models to determine the essential requirement for Cav-3 expression in protection against pharmacologically and pressure overload-induced cardiac hypertrophy. Transverse aortic constriction and angiotensin-II (Ang-II) infusion in wild type (WT) mice resulted in cardiac hypertrophy characterized by significant reduction in fractional shortening, ejection fraction, and a reduced expression of Cav-3. In addition, association of PKCα and angiotensin-II receptor, type 1, with Cav-3 was disrupted in the hypertrophic ventricular myocytes. Whole cell patch clamp analysis demonstrated increased expression of T-type Ca2+ current (ICa, T) in hypertrophic ventricular myocytes. In contrast, the Cav-3-overexpressing mice demonstrated protection from transverse aortic constriction or Ang-II-induced pathological hypertrophy with inhibition of ICa, T and intact Cav-3-associated macromolecular signaling complexes. siRNA-mediated knockdown of Cav-3 in the neonatal cardiomyocytes resulted in enhanced Ang-II stimulation of ICa, T mediated by PKCα, which caused nuclear translocation of NFAT. Overexpression of Cav-3 in neonatal myocytes prevented a PKCα-mediated increase in ICa, T and nuclear translocation of NFAT. In conclusion, we show that stable Cav-3 expression is essential for protecting the signaling mechanisms in pharmacologically and pressure overload-induced cardiac hypertrophy. PMID:26170457
Compensatory Hypertrophy Induced by Ventricular Cardiomyocyte Specific COX-2 Expression in Mice
Streicher, John M.; Kamei, Kenichiro; Ishikawa, Tomo-o; Herschman, Harvey; Wang, Yibin
2010-01-01
Cyclooxygenase-2 (COX-2) is an important mediator of inflammation in stress and disease states. Recent attention has focused on the role of COX-2 in human heart failure and diseases, due to the finding that highly specific COX-2 inhibitors (i.e. Vioxx) increased the risk of myocardial infarction and stroke in chronic users. However, the specific impact of COX-2 expression in the intact heart remains to be determined. We report here the development of a transgenic mouse model, using a loxP-Cre approach, that displays robust COX-2 overexpression and subsequent prostaglandin synthesis specifically in ventricular myocytes. Histological, functional and molecular analyses showed that ventricular myocyte specific COX-2 overexpression led to cardiac hypertrophy and fetal gene marker activation, but with preserved cardiac function. Therefore, specific induction of COX-2 and prostaglandin in vivo is sufficient to induce compensated hypertrophy and molecular remodeling. PMID:20170663
Zhang, Xinlu; Wang, Xu; Hu, Feng; Zhou, Boda; Chen, Hai-Bin; Zha, Daogang; Liu, Yili; Guo, Yansong; Zheng, Lemin; Xiu, Jiancheng
Drag-reducing polymers (DRPs), when added in minute concentrations, have been shown to decrease peripheral vascular resistance. In this study, the effect of DRPs on the hypertension-induced left ventricular hypertrophy and aortic remodeling was evaluated in spontaneously hypertensive rats (SHR). Male SHR and age-matched Wistar rats were divided into four groups and received intravenous injection of normal saline (NS) or DRPs. Body weight (BW), heart rate (HR) and systolic blood pressure (SBP) were measured. Echocardiography was used to evaluate the changes in left ventricle (LV) function and global wall motion. The LV and aorta were stained by hematoxylin and eosin. Cell size of cardiomyocytes and aortic medial thickness were evaluated for each section. The expression of endothelin-1 (ET-1) of LV and aorta was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. There was no significant difference in the increase of SBP among SHR + NS, SHR + 10DRP and SHR + 20DRP groups. SHR + NS group had markedly smaller left ventricular end-systolic diameter and left ventricular end-diastolic diameter but bigger anterior and posterior systolic wall thicknesses, while there was no significant difference in fractional shortening and ejection fraction. The cross-sectional areas (CSAs) of cardiomyocytes and the medial thickness of the aorta in SHR + 10 (ppm) DRP and SHR + 20 (ppm) DRP groups were significantly reduced compared with SHR + NS group. The expression of ET-1 in SHR + 10DRP and SHR + 20DRP groups was significantly attenuated. These results suggest that chronic treatment with DRPs can protect against left ventricular hypertrophy and aortic remodeling. DRPs may offer a new approach to the treatment of left ventricular hypertrophy and aortic remodeling caused by hypertension.
Zhang, Xinlu; Wang, Xu; Hu, Feng; Zhou, Boda; Chen, Hai-Bin; Zha, Daogang; Liu, Yili; Guo, Yansong; Zheng, Lemin; Xiu, Jiancheng
2016-01-01
Drag-reducing polymers (DRPs), when added in minute concentrations, have been shown to decrease peripheral vascular resistance. In this study, the effect of DRPs on the hypertension-induced left ventricular hypertrophy and aortic remodeling was evaluated in spontaneously hypertensive rats (SHR). Male SHR and age-matched Wistar rats were divided into four groups and received intravenous injection of normal saline (NS) or DRPs. Body weight (BW), heart rate (HR) and systolic blood pressure (SBP) were measured. Echocardiography was used to evaluate the changes in left ventricle (LV) function and global wall motion. The LV and aorta were stained by hematoxylin and eosin. Cell size of cardiomyocytes and aortic medial thickness were evaluated for each section. The expression of endothelin-1 (ET-1) of LV and aorta was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. There was no significant difference in the increase of SBP among SHR + NS, SHR + 10DRP and SHR + 20DRP groups. SHR + NS group had markedly smaller left ventricular end-systolic diameter and left ventricular end-diastolic diameter but bigger anterior and posterior systolic wall thicknesses, while there was no significant difference in fractional shortening and ejection fraction. The cross-sectional areas (CSAs) of cardiomyocytes and the medial thickness of the aorta in SHR + 10 (ppm) DRP and SHR + 20 (ppm) DRP groups were significantly reduced compared with SHR + NS group. The expression of ET-1 in SHR + 10DRP and SHR + 20DRP groups was significantly attenuated. These results suggest that chronic treatment with DRPs can protect against left ventricular hypertrophy and aortic remodeling. DRPs may offer a new approach to the treatment of left ventricular hypertrophy and aortic remodeling caused by hypertension. PMID:28008249
Aldosterone is associated with left ventricular hypertrophy in hemodialysis patients.
Feniman De Stefano, Greicy Mara Mengue; Zanati-Basan, Silméia Garcia; De Stefano, Laercio Martins; Silva, Viviana Rugolo Oliveira E; Xavier, Patrícia Santi; Barretti, Pasqual; da Silva Franco, Roberto Jorge; Caramori, Jacqueline Costa Teixeira; Martin, Luis Cuadrado
2016-10-01
Patients with chronic kidney disease present a higher degree of left ventricular hypertrophy than expected for hypertension levels. In chronic kidney disease the plot between the quotient extracellular water/total body water and aldosterone is shifted up and to the right. There are few studies that verified the role of aldosterone in cardiac remodeling in this set of patients. The aim of this study was to evaluate the relationship between serum aldosterone and left ventricular mass index in patients with chronic kidney disease on hemodialysis. The patients were submitted to clinical and laboratory evaluation, bioelectrical impedance, echocardiography and ambulatory blood pressure monitoring. The 27 patients included were divided into two groups according to aldosterone level and compared with each other. The group of patients with higher aldosterone levels had higher left ventricular mass index. These groups were heterogeneous with regard to ambulatory systolic blood pressure, body mass index, and aldosterone levels and homogeneous with regard to the quotient extracellular water/total body water, renin-angiotensin-aldosterone system blockers, beta blocker use and other clinical characteristics. The association between aldosterone levels and left ventricular mass index was adjusted to confounding variables by a multiple linear regression analysis in which aldosterone was independently associated with left ventricular mass index. The data presented are consistent with a pathogenic role of aldosterone in left ventricular hypertrophy in patients with chronic kidney dialysis in dialysis patients. ClinicalTrials.gov identifier: NCT01128101. © The Author(s), 2016.
USDA-ARS?s Scientific Manuscript database
Chronic hypobaric hypoxia (CHH) increases load on the right ventricle (RV) resulting in RV hypertrophy. We hypothesized that CHH elicits distinct responses, i.e., the hypertrophied RV, unlike the left ventricle (LV), displaying enhanced mitochondrial respiratory and contractile function. Wistar rats...
Electrocardiographic recognition of right ventricular hypertrophy.
Nikus, Kjell; Pérez-Riera, Andrés Ricardo; Konttila, Kaari; Barbosa-Barros, Raimundo
The electrocardiogram (ECG) is a relatively insensitive tool for the detection of right ventricular hypertrophy (RVH), but some criteria have high specificity. The recommended ECG screening criteria for RVH are not sufficiently sensitive or specific for screening for mild RVH in adults without clinical cardiovascular disease. The greatest accuracy of the ECG is in congenital heart disease, with intermediate accuracy in acquired heart disease and primary pulmonary hypertension in adults. Copyright © 2017 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cabrera Sole, Ricardo
Objective: The main objective of this study was to evaluate the effects of the treatment with eprosartan on cardiac hypertrophy in hypertensive patients using the echocardiogram to measure the hypertrophy of left ventricle. We studied 60 untreated patients diagnosed of mild to moderate hypertension which received after the diagnosis 600 mg/day of eprosartan, a novel direct angiotensin inhibitor recently introduced to treat hypertension. All patients were submitted to a standard echocardiographic study before the treatment and after 6 months of it We evaluated by echocardiogram the following parameters: left ventricular septum and posterior wall thickness, left ventricular mass, E/A indexmore » of mitral flow considering abnormal when this index was less than 1, and left ventricular ejection fraction. Results: at the beginning we found a systolic/diastolic pressures of 165{+-}9/ 96{+-}4 mmHg compared with the end of study of 124{+-}2/79{+-}3 mmHg (p<0.05). Septum and posterior wall thickness were respectively at baseline 13.2{+-}2 and 12.1{+-}1.1 mmHg and at the end 11.5{+-}1.2 and 10.5{+-}1.3 mmHg (p<0.05 for both of them). The E/A mitral flow index was less than 1 at baseline in 45 patients compared with 19 patients after treatment (p<0.05). Respect to left ventricular mass we found at the beginning 232{+-}7.5 gr., compared to 194{+-}9 gr., at the end of this study (p<0.05). We did not find any significant differences regarding left ventricular ejection fraction between both groups. Conclusions: we can remark that eprosartan is a very useful drug to reduce not only blood pressure but also left ventricular hypertrophy and improve left ventricular diastolic function in patients with essential hypertension according with parameters measured with non invasive methods.« less
Growth of left ventricular mass with military basic training in army recruits.
Batterham, Alan M; George, Keith P; Birch, Karen M; Pennell, Dudley J; Myerson, Saul G
2011-07-01
Exercise-induced left ventricular hypertrophy is well documented, but whether this occurs merely in line with concomitant increases in lean body mass is unclear. Our aim was to model the extent of left ventricular hypertrophy associated with increased lean body mass attributable to an exercise training program. Cardiac and whole-body magnetic resonance imaging was performed before and after a 10-wk intensive British Army basic training program in a sample of 116 healthy Caucasian males (aged 17-28 yr). The within-subjects repeated-measures allometric relationship between lean body mass and left ventricular mass was modeled to allow the proper normalization of changes in left ventricular mass for attendant changes in lean body mass. To linearize the general allometric model (Y=aXb), data were log-transformed before analysis; the resulting effects were therefore expressed as percent changes. We quantified the probability that the true population increase in normalized left ventricular mass was greater than a predefined minimum important difference of 0.2 SD, assigning a probabilistic descriptive anchor for magnitude-based inference. The absolute increase in left ventricular mass was 4.8% (90% confidence interval=3.5%-6%), whereas lean body mass increased by 2.6% (2.1%-3.0%). The change in left ventricular mass adjusted for the change in lean body mass was 3.5% (1.9%-5.1%), equivalent to an increase of 0.25 SD (0.14-0.37). The probability that this effect size was greater than or equal to our predefined minimum important change of 0.2 SD was 0.78-likely to be important. After correction for allometric growth rates, left ventricular hypertrophy and lean body mass changes do not occur at the same magnitude in response to chronic exercise.
Barrios, V; Calderón, A; Coca, A; González-Juanatey, J R; Sarríá, A; Rodríguez-Padial, L
2011-09-01
Despite its low sensitivity, the electrocardiogram (ECG) is the tool used the most in the daily practice for detection of left ventricular hypertrophy (LVH). This study has aimed to assess the impact of the computerized interpretation of the ECG on the diagnosis of LVH in the practical clinical setting. ELECTROPRES is a project based on a free access computer platform that permits an online interpretation of the electrocardiogram. It includes 19 different left LVH criteria previously validated by echocardiography in a substudy. We analyzed the data from the first 669 patients with essential arterial hypertension (ATH) included in the ELECTROPRES platform from 21 primary care centers in 9 of the 17 Spanish autonomous communities. Up to April 2010, a cohort of 669 hypertensive patients (51.7% women), with a mean age of 66.3±11.89 years, was analyzed. The mean evolution of the disease was 8 years, and the patients had been receiving an average of 2.4 antihypertensive agents. Systolic blood pressure was 139±17 mmHg and diastolic blood pressure 76±11. The ECG-known frequency of LVH was 3%. The prevalence of LVH increased up to 33.3% (P<0.001) with the ELECTROPRES platform. When all the criteria were independently examined, the Lewis index (R-I+S-III) and the Cornell product [(R-aVL+S-V3 (+6 for women)] were those in which the most cases of left ventricular hypertrophy were detected (24.8% and 13.3%, respectively). The Lewis index and the Cornell product were the criteria that detected more cases of left ventricular hypertrophy, regardless of the AHT stage and of the presence of cardiovascular complications. The ECG computerized reading (ELECTROPRES platform) significantly increases detection of left ventricular hypertrophy in a population of essential hypertense subjects compared to conventional detection with the ECG by the physician in the usual clinical practice setting. Copyright © 2011 Elsevier España, S.L. All rights reserved.
Røe, Åsmund T.; Aronsen, Jan Magnus; Skårdal, Kristine; Hamdani, Nazha; Linke, Wolfgang A.; Danielsen, Håvard E.; Sejersted, Ole M.; Sjaastad, Ivar; Louch, William E.
2017-01-01
Abstract Aims Concentric hypertrophy following pressure-overload is linked to preserved systolic function but impaired diastolic function, and is an important substrate for heart failure with preserved ejection fraction. While increased passive stiffness of the myocardium is a suggested mechanism underlying diastolic dysfunction in these hearts, the contribution of active diastolic Ca2+ cycling in cardiomyocytes remains unclear. In this study, we sought to dissect contributions of passive and active mechanisms to diastolic dysfunction in the concentrically hypertrophied heart following pressure-overload. Methods and results Rats were subjected to aortic banding (AB), and experiments were performed 6 weeks after surgery using sham-operated rats as controls. In vivo ejection fraction and fractional shortening were normal, confirming preservation of systolic function. Left ventricular concentric hypertrophy and diastolic dysfunction following AB were indicated by thickening of the ventricular wall, reduced peak early diastolic tissue velocity, and higher E/e’ values. Slowed relaxation was also observed in left ventricular muscle strips isolated from AB hearts, during both isometric and isotonic stimulation, and accompanied by increases in passive tension, viscosity, and extracellular collagen. An altered titin phosphorylation profile was observed with hypophosphorylation of the phosphosites S4080 and S3991 sites within the N2Bus, and S12884 within the PEVK region. Increased titin-based stiffness was confirmed by salt-extraction experiments. In contrast, isolated, unloaded cardiomyocytes exhibited accelerated relaxation in AB compared to sham, and less contracture at high pacing frequencies. Parallel enhancement of diastolic Ca2+ handling was observed, with augmented NCX and SERCA2 activity and lowered resting cytosolic [Ca2+]. Conclusion In the hypertrophied heart with preserved systolic function, in vivo diastolic dysfunction develops as cardiac fibrosis and alterations in titin phosphorylation compromise left ventricular compliance, and despite compensatory changes in cardiomyocyte Ca2+ homeostasis. PMID:28472418
Moon, James C C; Sachdev, Bhavesh; Elkington, Andrew G; McKenna, William J; Mehta, Atul; Pennell, Dudley J; Leed, Philip J; Elliott, Perry M
2003-12-01
Anderson-Fabry Disease (AFD), an X-linked disorder of sphingolipid metabolism, is a cause of idiopathic left ventricular hypertrophy but the mechanism of hypertrophy is poorly understood. Gadolinium enhanced cardiovascular magnetic resonance can detect focal myocardial fibrosis. We hypothesised that hyperenhancement would be present in AFD. Eighteen males (mean 43+/-14 years) and eight female heterozygotes (mean 48+/-12 years) with AFD underwent cine and late gadolinium cardiovascular magnetic resonance. Nine male (50%) had myocardial hyperenhancement ranging from 3.4% to 20.6% (mean 7.7+/-5.7%) of total myocardium; in males, percentage hyperenhancement related to LV mass index (r=0.78, P=0.0002) but not to ejection fraction or left ventricular volumes. Lesser hyperenhancement was also found in four (50%) heterozygous females (mean 4.6%). In 12 (92%) patients with abnormal gadolinium uptake, hyperenhancement occurred in the basal infero-lateral wall where, unlike myocardial infarction, it was not sub-endocardial. In two male patients with severe LVH (left ventricular hypertrophy) and systolic impairment there was additional hyperenhancement in other myocardial segments. These observations suggests that myocardial fibrosis occurs in AFD and may contribute to the hypertrophy and the natural history of the disease.
Severe right ventricular hypertrophy in a patient with extracardiac and intracardiac shunt.
Pahuja, Mohit; Abidov, Aiden
2018-06-10
Cardiac MRI is a complementary and confirmatory modality to a clinical echocardiography in diagnosing patients with complex adult congenital heart disease, especially in presence of great vessel abnormalities. We present a unique case of a patient with pulmonary hypertension (PH), severe right ventricular hypertrophy, Gerbode defect, and a large patent ductus arteriosus (PDA). The diagnosis of PDA was not visualized on prior serial echocardiograms and discovered on a comprehensive cardiac MRI/Chest MR angiogram. © 2018 Wiley Periodicals, Inc.
Xu, Xin; Hu, Xinli; Lu, Zhongbing; Zhang, Ping; Zhao, Lin; Wessale, Jerry L.; Bache, Robert J.; Chen, Yingjie
2008-01-01
The purine analog xanthine oxidase (XO) inhibitors (XOIs), allopurinol and oxypurinol, have been reported to protect against heart failure secondary to myocardial infarction or rapid ventricular pacing. Since these agents might influence other aspects of purine metabolism that could influence their effect, this study examined the effect of the non-purine XOI, febuxostat, on pressure overload-induced left ventricular (LV) hypertrophy and dysfunction. Transverse aortic constriction (TAC) in mice caused LV hypertrophy and dysfunction as well as increased myocardial nitrotyrosine at 8 days. TAC also caused increased phosphorylated Akt (p-AktSer473), p42/44 extracellular signal-regulated kinase (p-ErkThr202/Tyr204) and mammalian target of rapamycin (mTOR) (p-mTORSer2488). XO inhibition with febuxostat (5mg/kg/day by gavage for 8 days) beginning ~60 minutes after TAC attenuated the TAC-induced LV hypertrophy and dysfunction. Febuxostat blunted the TAC-induced increases in nitrotyrosine (indicating reduced myocardial oxidative stress), p-ErkThr202/Tyr204 and p-mTORSer2488, with no effect on total Erk or total mTOR. Febuxostat had no effect on myocardial p-AktSer473 or total Akt. The results suggest that XO inhibition with febuxostat reduced oxidative stress in the pressure overloaded LV, thereby diminishing the activation of pathways that result in pathologic hypertrophy and contractile dysfunction. PMID:18995179
Dai, Fengdan; Zhang, Yan; Wang, Qiang; Li, De; Yang, Yongjian; Ma, Shuangtao; Yang, Dachun
2018-01-01
Activation of stromal interaction molecule 1 (STIM1) and Orai1 participates in the development of cardiac hypertrophy. Store-operated Ca2+ entry-associated regulatory factor (SARAF) is an intrinsic inhibitor of STIM1-Orai1 interaction. Thus, we hypothesized that SARAF could prevent cardiac hypertrophy. Male C57BL/6 mice, aged 8 weeks, were randomly divided into sham and abdominal aortic constriction surgery groups and were infected with lentiviruses expressing SARAF and GFP (Lenti-SARAF) or GFP alone (Lenti-GFP) via intramyocardial injection. At 4 weeks after aortic constriction, left ventricular structure and function were assessed by echocardiography and hemodynamic assays. The gene and protein expressions of SARAF, STIM1, and Orai1 were measured by quantitative PCR and Western blot, respectively. Gene and protein expressions of SARAF were significantly decreased, while STIM1 and Orai1 were increased in the heart tissue compared with sham group. Overexpression of SARAF in the heart prevented the upregulation of STIM1 and Orai1, and importantly, attenuated aortic constriction-induced decrease in maximal rate of left ventricular pressure decay and increases in thickness of interventricular septum and left ventricular posterior wall, heart weight/body weight ratio, and size of cardiomyocytes. Blood pressure detected through the carotid artery and left ventricular systolic function were not affected by SARAF overexpression. In addition, overexpression of SARAF also attenuated angiotensin II-induced upregulation of STIM1 and Orai1 and hypertrophy of cultured cardiomyocytes. Overexpression of SARAF in the heart prevents cardiac hypertrophy, probably through suppressing the upregulation of STIM1/Orai1. © 2018 The Author(s). Published by S. Karger AG, Basel.
Curcio, Antonio; Torella, Daniele; Iaconetti, Claudio; Pasceri, Eugenia; Sabatino, Jolanda; Sorrentino, Sabato; Giampà, Salvatore; Micieli, Mariella; Polimeni, Alberto; Henning, Beverley J.; Leone, Angelo; Catalucci, Daniele; Ellison, Georgina M.; Condorelli, Gianluigi; Indolfi, Ciro
2013-01-01
Downregulation of the muscle-specific microRNA-1 (miR-1) mediates the induction of pathologic cardiac hypertrophy. Dysfunction of the gap junction protein connexin 43 (Cx43), an established miR-1 target, during cardiac hypertrophy leads to ventricular tachyarrhythmias (VT). However, it is still unknown whether miR-1 and Cx43 are interconnected in the pro-arrhythmic context of hypertrophy. Thus, in this study we investigated whether a reduction in the extent of cardiac hypertrophy could limit the pathological electrical remodeling of Cx43 and the onset of VT by modulating miR-1 levels. Wistar male rats underwent mechanical constriction of the ascending aorta to induce pathologic left ventricular hypertrophy (LVH) and afterwards were randomly assigned to receive 10mg/kg valsartan, VAL (LVH+VAL) delivered in the drinking water or placebo (LVH) for 12 weeks. Sham surgery was performed for control groups. Programmed ventricular stimulation reproducibly induced VT in LVH compared to LVH+VAL group. When compared to sham controls, rats from LVH group showed a significant decrease of miR-1 and an increase of Cx43 expression and its ERK1/2-dependent phosphorylation, which displaces Cx43 from the gap junction. Interestingly, VAL administration to rats with aortic banding significantly reduced cardiac hypertrophy and prevented miR-1 down-regulation and Cx43 up-regulation and phosphorylation. Gain- and loss-of-function experiments in neonatal cardiomyocytes (NCMs) in vitro confirmed that Cx43 is a direct target of miR-1. Accordingly, in vitro angiotensin II stimulation reduced miR-1 levels and increased Cx43 expression and phosphorylation compared to un-stimulated NCMs. Finally, in vivo miR-1 cardiac overexpression by an adenoviral vector intra-myocardial injection reduced Cx43 expression and phosphorylation in mice with isoproterenol-induced LVH. In conclusion, miR-1 regulates Cx43 expression and activity in hypertrophic cardiomyocytes in vitro and in vivo. Treatment of pressure overload-induced myocyte hypertrophy reduces the risk of life-threatening VT by normalizing miR-1 expression levels with the consequent stabilization of Cx43 expression and activity within the gap junction. PMID:23922949
Jessica, Sabourin; Angèle, Boet; Catherine, Rucker-Martin; Mélanie, Lambert; Ana-Maria, Gomez; Jean-Pierre, Benitah; Frédéric, Perros; Marc, Humbert; Fabrice, Antigny
2018-05-01
Right ventricular (RV) function is the most important prognostic factor for pulmonary arterial hypertension (PAH) patients. The progressive increase of pulmonary vascular resistance induces RV hypertrophy (RVH) and at term RV failure (RVF). However, the molecular mechanisms of RVH and RVF remain understudied. In this study, we gained insights into cytosolic Ca 2+ signaling remodeling in ventricular cardiomyocytes during the pathogenesis of severe pulmonary hypertension (PH) induced in rats by monocrotaline (MCT) exposure, and we further identified molecular candidates responsible for this Ca 2+ remodeling. After PH induction, hypertrophied RV myocytes presented longer action potential duration, higher and faster [Ca 2+ ] i transients and increased sarcoplasmic reticulum (SR) Ca 2+ content, whereas no changes in these parameters were detected in left ventricular (LV) myocytes. These modifications were associated with increased P-Ser 16 -phospholamban pentamer expression without altering SERCA2a (Sarco/Endoplasmic Reticulum Ca 2+ -ATPase) pump abundance. Moreover, after PH induction, Ca 2+ sparks frequency were higher in hypertrophied RV cells, while total RyR2 (Ryanodine Receptor) expression and phosphorylation were unaffected. Together with cellular hypertrophy, the T-tubules network was disorganized. Hypertrophied RV cardiomyocytes from MCT-exposed rats showed decreased expression of classical STIM1 (Stromal Interaction molecule) associated with increased expression of muscle-specific STIM1 Long isoform, glycosylated-Orai1 channel form, and TRPC1 and TRPC4 channels, which was correlated with an enhanced Ca 2+ -release-activated Ca 2+ (CRAC)-like current. Pharmacological inhibition of TRPCs/Orai1 channels in hypertrophied RV cardiomyocytes normalized [Ca 2+ ] i transients amplitude, the SR Ca 2+ content and cell contractility to control levels. Finally, we showed that most of these changes did not appear in LV cardiomyocytes. These new findings demonstrate RV-specific cellular Ca 2+ cycling remodeling in PH rats with maladaptive RVH and that the STIM1L/Orai1/TRPC1/C4-dependent Ca 2+ current participates in this Ca 2+ remodeling in RVH secondary to PH. Copyright © 2018 Elsevier Ltd. All rights reserved.
Major new developments affecting treatment and prognosis in hypertension.
Gubner, R S
1990-01-01
Joint studies of the ALIMDA and Society of Actuaries, notably those of 1935, 1959 and 1979, established that there is a progressive rise in cardiovascular mortality with successive increments in blood pressure. This has provided the basis of underwriting. The converse is not true, or at least has not been true until very recently. Drugs that effectively reduce blood pressure have been available for several decades, but reduction and maintenance of blood pressure is still accomplished in only a minority of hypertensives. Long-term trials employing a combination of drugs, i.e., diuretics, vasodilators and reserpine and subsequently beta-blockers, almost without fail have not shown that treatment with these agents significantly reduces heart disease mortality and sudden death. This has been attributed, perhaps without basis, to an unfavorable countering effect of increased lipid levels, aggravating this risk factor, and other undesirable metabolic effect of diuretics, such as hypokalemia and depletion of body magnesium, increasing the propensity to ventricular arrhythmias, hyperglycemia, worsening diabetes, and hyperuricemia. A survey of 674 persons with hypertension seen personally during the period 1985-89, who were under the care of approximately that many physicians, reveals striking changes in drug prescription and use during this brief period that portend a major change in the outlook of hypertension. Two classes of drugs have increased rapidly in popularity: these are the angiotensin-converting enzyme inhibitors (ACE inhibitors) and the calcium blockers. Both classes of drugs effectively lower blood pressure and have minimal side effects with good compliance. They act not only to reduce peripheral vascular resistance, but also locally in the heart muscle to directly cause left ventricular hypertrophy to regress, an effect of great consequence. The drugs used in former trials such as the vasodilators and diuretics have no effect on left ventricular hypertrophy, unlike the ACE inhibitors and calcium antagonists. Left ventricular hypertrophy is the key lesion in hypertension and is only in part due to increased work load imposed by elevated pressure. It is associated with elevated blood pressure, but not closely and occurs independently; ventricular myocytes as well as myocytes of the vasculature being stimulated to growth by angiotensin and calcium, potentiating the effect of norepinephrine. Left ventricular hypertrophy greatly increases the propensity to ventricular arrhythmias and sudden death, and is a prime cause of cardiac mortality and sudden death not only in hypertension, but also in obesity, aging and diabetes, in which conditions left ventricular hypertrophy also is very common.(ABSTRACT TRUNCATED AT 400 WORDS)
Weber, Thomas; Wassertheurer, Siegfried; Schmidt-Trucksäss, Arno; Rodilla, Enrique; Ablasser, Cornelia; Jankowski, Piotr; Lorenza Muiesan, Maria; Giannattasio, Cristina; Mang, Claudia; Wilkinson, Ian; Kellermair, Jörg; Hametner, Bernhard; Pascual, Jose Maria; Zweiker, Robert; Czarnecka, Danuta; Paini, Anna; Salvetti, Massimo; Maloberti, Alessandro; McEniery, Carmel
2017-12-01
We investigated the relationship between left ventricular mass and brachial office as well as brachial and central ambulatory systolic blood pressure in 7 European centers. Central systolic pressure was measured with a validated oscillometric device, using a transfer function, and mean/diastolic pressure calibration. M-mode images were obtained by echocardiography, and left ventricular mass was determined by one single reader blinded to blood pressure. We studied 289 participants (137 women) free from antihypertensive drugs (mean age: 50.8 years). Mean office blood pressure was 145/88 mm Hg and mean brachial and central ambulatory systolic pressures were 127 and 128 mm Hg, respectively. Mean left ventricular mass was 93.3 kg/m 2 , and 25.6% had left ventricular hypertrophy. The correlation coefficient between left ventricular mass and brachial office, brachial ambulatory, and central ambulatory systolic pressure was 0.29, 0.41, and 0.47, respectively ( P =0.003 for comparison between brachial office and central ambulatory systolic pressure and 0.32 for comparison between brachial and central ambulatory systolic pressure). The results were consistent for men and women, and young and old participants. The areas under the curve for prediction of left ventricular hypertrophy were 0.618, 0.635, and 0.666 for brachial office, brachial, and central ambulatory systolic pressure, respectively ( P =0.03 for comparison between brachial and central ambulatory systolic pressure). In younger participants, central ambulatory systolic pressure was superior to both other measurements. Central ambulatory systolic pressure, measured with an oscillometric cuff, shows a strong trend toward a closer association with left ventricular mass and hypertrophy than brachial office/ambulatory systolic pressure. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01278732. © 2017 American Heart Association, Inc.
Ahmad, Faraz S; Cai, Xuan; Kunkel, Katherine; Ricardo, Ana C; Lash, James P; Raj, Dominic S; He, Jiang; Anderson, Amanda H; Budoff, Matthew J; Wright Nunes, Julie A; Roy, Jason; Wright, Jackson T; Go, Alan S; St John Sutton, Martin G; Kusek, John W; Isakova, Tamara; Wolf, Myles; Keane, Martin G
2017-08-01
Chronic kidney disease (CKD) is associated with increased risk of cardiovascular disease (CVD) and it is especially common among Blacks. Left ventricular hypertrophy (LVH) is an important subclinical marker of CVD, but there are limited data on racial variation in left ventricular structure and function among persons with CKD. In a cross-sectional analysis of the Chronic Renal Insufficiency Cohort Study, we compared the prevalence of different types of left ventricular remodeling (concentric hypertrophy, eccentric hypertrophy, and concentric remodeling) by race/ethnicity. We used multinomial logistic regression to test whether race/ethnicity associated with different types of left ventricular remodeling independently of potential confounding factors. We identified 1,164 non-Hispanic Black and 1,155 non-Hispanic White participants who completed Year 1 visits with echocardiograms that had sufficient data to categorize left ventricular geometry type. Compared to non-Hispanic Whites, non-Hispanic Blacks had higher mean left ventricular mass index (54.7 ± 14.6 vs. 47.4 ± 12.2 g/m2.7; P < 0.0001) and prevalence of concentric LVH (45.8% vs. 24.9%). In addition to higher systolic blood pressure and treatment with >3 antihypertensive medications, Black race/ethnicity was independently associated with higher odds of concentric LVH compared to White race/ethnicity (odds ratio: 2.73; 95% confidence interval: 2.02, 3.69). In a large, diverse cohort with CKD, we found significant differences in left ventricular mass and hypertrophic morphology between non-Hispanic Blacks and Whites. Future studies will evaluate whether higher prevalence of LVH contribute to racial/ethnic disparities in cardiovascular outcomes among CKD patients. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Picca, Maurizio; Agozzino, Francesco; Pelosi, Giancarlo
2003-01-01
An increased urinary albumin excretion (UAE) is associated with an augmented risk of cardiovascular disease in diabetic patients and in non-diabetic subjects. Left ventricular hypertrophy has been demonstrated to be a powerful predictor of cardiovascular morbidity and mortality in arterial hypertension and when the ventricular geometry is concentric the relation is even stronger. This echocardiographic and Doppler study was designed to evaluate the influence of microalbuminuria on the left ventricular geometry and function in hypertensive patients with type 2 diabetes melitus. Forty-two patients (16 males, 26 females, mean age 59.6 +/- 6.7 years) with mild-to-moderate essential hypertension and type 2 diabetes mellitus were enrolled in the study. Twenty-one patients had an elevated UAE (group 1) and 21 a normal UAE (group 2). M-mode (under two-dimensional control) and Doppler echocardiography were performed after a 4-week washout period off antihypertensive therapy. The left ventricular mass index was found to be greater than the partition value of 51 g/m2.7 in both groups but was significantly higher (p < 0.001) in group 1. The midwall fractional shortening was significantly lower (p < 0.001) in group 1 in comparison with group 2. The E/A ratio was impaired in both groups but was more significantly reduced (p < 0.02) in group 1. There was a significantly higher prevalence of a left ventricular concentric hypertrophy pattern (19/21 patients, p < 0.001) in group 1. In hypertensive patients with type 2 diabetes mellitus, an elevated UAE is associated with an increased left ventricular mass index, a higher prevalence of a concentric left ventricular hypertrophy pattern, a depressed midwall systolic performance and a markedly impaired diastolic function...
Sah, Rajan; Mesirca, Pietro; Mason, Xenos; Gibson, William; Bates-Withers, Christopher; Van den Boogert, Marjolein; Chaudhuri, Dipayan; Pu, William T; Mangoni, Matteo E; Clapham, David E
2013-07-09
Transient receptor potential (TRP) channels are a superfamily of broadly expressed ion channels with diverse physiological roles. TRPC1, TRPC3, and TRPC6 are believed to contribute to cardiac hypertrophy in mouse models. Human mutations in TRPM4 have been linked to progressive familial heart block. TRPM7 is a divalent-permeant channel and kinase of unknown function, recently implicated in the pathogenesis of atrial fibrillation; however, its function in ventricular myocardium remains unexplored. We generated multiple cardiac-targeted knockout mice to test the hypothesis that TRPM7 is required for normal ventricular function. Early cardiac Trpm7 deletion (before embryonic day 9; TnT/Isl1-Cre) results in congestive heart failure and death by embryonic day 11.5 as a result of hypoproliferation of the compact myocardium. Remarkably, Trpm7 deletion late in cardiogenesis (about embryonic day 13; αMHC-Cre) produces viable mice with normal adult ventricular size, function, and myocardial transcriptional profile. Trpm7 deletion at an intermediate time point results in 50% of mice developing cardiomyopathy associated with heart block, impaired repolarization, and ventricular arrhythmias. Microarray analysis reveals elevations in transcripts of hypertrophy/remodeling genes and reductions in genes important for suppressing hypertrophy (Hdac9) and for ventricular repolarization (Kcnd2) and conduction (Hcn4). These transcriptional changes are accompanied by action potential prolongation and reductions in transient outward current (Ito; Kcnd2). Similarly, the pacemaker current (If; Hcn4) is suppressed in atrioventricular nodal cells, accounting for the observed heart block. Trpm7 is dispensable in adult ventricular myocardium under basal conditions but is critical for myocardial proliferation during early cardiogenesis. Loss of Trpm7 at an intermediate developmental time point alters the myocardial transcriptional profile in adulthood, impairing ventricular function, conduction, and repolarization.
Left Ventricular Hypertrophy: An allometric comparative analysis of different ECG markers
NASA Astrophysics Data System (ADS)
Bonomini, M. P.; Ingallina, F.; Barone, V.; Valentinuzzi, M. E.; Arini, P. D.
2011-12-01
Allometry, in general biology, measures the relative growth of a part in relation to the whole living organism. Left ventricular hypertrophy (LVH) is the heart adaptation to excessive load (systolic or diastolic). The increase in left ventricular mass leads to an increase in the electrocardiographic voltages. Based on clinical data, we compared the allometric behavior of three different ECG markers of LVH. To do this, the allometric fit AECG = δ + β (VM) relating left ventricular mass (estimated from ecocardiographic data) and ECG amplitudes (expressed as the Cornell-Voltage, Sokolow and the ECG overall voltage indexes) were compared. Besides, sensitivity and specifity for each index were analyzed. The more sensitive the ECG criteria, the better the allometric fit. In conclusion: The allometric paradigm should be regarded as the way to design new and more sensitive ECG-based LVH markers.
Lung function and left ventricular hypertrophy in morbidly obese candidates for bariatric surgery
Müller, Paulo de Tarso; Domingos, Hamilton; Patusco, Luiz Armando Pereira; Rapello, Gabriel Victor Guimarães
2015-01-01
Objective: To look for correlations between lung function and cardiac dimension variables in morbidly obese patients, in order to test the hypothesis that the relative size of the small airways is independently correlated with left ventricular hypertrophy. Methods: This was a retrospective study involving 192 medical records containing a clinical protocol employed in candidates for bariatric surgery between January of 2006 and December of 2010. Results: Of the 192 patients evaluated, 39 (10 males and 29 females) met the inclusion criteria. The mean BMI of the patients was 49.2 ± 7.6 kg/m2, and the mean age was 35.5 ± 7.7 years. The FEF25-75/FVC, % correlated significantly with left ventricular posterior wall thickness and relative left ventricular posterior wall thickness, those correlations remaining statistically significant (r = −0.355 and r = −0.349, respectively) after adjustment for weight, gender, and history of systemic arterial hypertension. Stepwise multivariate linear regression analysis showed that FVC and FEV1 were the major determinants of left ventricular mass (in grams or indexed to body surface area). Conclusions: A reduction in the relative size of the small airways appears to be independently correlated with obesity-related cardiac hypertrophy, regardless of factors affecting respiratory mechanics (BMI and weight), gender, or history of systemic arterial hypertension. However, FEV1 and FVC might be important predictors of left ventricular mass in morbidly obese individuals. PMID:26578134
Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance
van Geuns, Robert‐Jan; Ainslie, Gillian; Ector, Joris; Heidbuchel, Hein; Crijns, Harry J.G.M.
2017-01-01
Abstract Aims Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast‐enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis. Methods and results We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast‐enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non‐invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P < 0.001). Right ventricular enhancement correlated with systolic ventricular dysfunction (P < 0.001), hypertrophy (P = 0.001), and dilation (P < 0.001). Conclusions Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation. PMID:29154434
[Role of cardiac magnetic resonance in cardiac involvement of Fabry disease].
Serra, Viviana M; Barba, Miguel Angel; Torrá, Roser; Pérez De Isla, Leopoldo; López, Mónica; Calli, Andrea; Feltes, Gisela; Torras, Joan; Valverde, Victor; Zamorano, José L
2010-09-04
Fabry disease is a hereditary disorder. Clinical manifestations are multisystemic. The majority of the patients remain undiagnosed until late in life, when alterations could be irreversible. Early detection of cardiac symptoms is of major interest in Fabry's disease (FD) in order to gain access to enzyme replacement therapy. Echo-Doppler tissular imaging (TDI) has been used as a cardiologic early marker in FD. This study is intended to determine whether the cardiac magnetic resonance is as useful tool as TDI for the early detection of cardiac affectation in FD. Echocardiography, tissue Doppler and Cardio magnetic resonance was performed in 20 patients with confirmed Fabry Disease. Left ventricular hypertrophy was defined as septum and left ventricular posterior wall thickness ≥12 mm. An abnormal TDI velocity was defined as (Sa), (Ea) and/or (Aa) velocities <8 cm/s at either the septal or lateral corner. Late phase gadolinium-enhanced images sequences were obtained using magnetic resonance. Twenty patients included in the study were divided into three groups: 1. Those without left ventricular hypertrophy nor tissue Doppler impairment 2. Those without left ventricular hypertrophy and tissue Doppler impairment 3. Those with left ventricular hypertrophy and Tissue Doppler impairment. Late gadolinium enhancement was found in only one patient, who has already altered DTI and LVH. Tissue Doppler imaging (TDI) is the only diagnostic tool able to provide early detection of cardiac affectation in patients with FD. Magnetic resonance provides information of the disease severity in patients with LVH, but can not be used as an early marker of cardiac disease in patients with FD. However MRI could be of great value for diagnostic stratification. Copyright © 2009 Elsevier España, S.L. All rights reserved.
Ji, Xiao-Bing; Li, Xiu-Rong; Hao-Ding; Sun, Qi; Zhou, Yang; Wen, Ping; Dai, Chun-Sun; Yang, Jun-Wei
2015-01-01
Uncoupling protein 2 (UCP2) is critical in regulating energy metabolism. Due to the significant change in energy metabolism of myocardium upon pressure overload, we hypothesize that UCP2 could contribute to the etiology of cardiac hypertrophy. Adult male C57BL/6J mice were subjected to pressure overload by using transverse aortic constriction (TAC), and then received genipin (a UCP2 selective inhibitor; 25 mg/kg/d, ip) or vehicle for three weeks prior to histologic assessment of myocardial hypertrophy. ATP concentration, ROS level, and myocardial apoptosis were also examined. A parallel set of experiments was also conducted in UCP2-/- mice. TAC induced left ventricular hypertrophy, as reflected by increased ventricular weight/thickness and increased size of myocardial cell (vs. sham controls). ATP concentration was decreased; ROS level was increased. Apoptosis and fibrosis markers were increased. TAC increased mitochondrial UCP2 expression in the myocardium at both mRNA and protein levels. Genipin treatment attenuated cardiac hypertrophy and the histologic/biochemical changes described above. Hypertrophy and associated changes induced by TAC in UCP2-/- mice were much less pronounced than in WT mice. Blocking UCP2 expression attenuates cardiac hypertrophy induced by pressure overload. © 2015 S. Karger AG, Basel.
Denesiuk, E V
2015-01-01
The study involved 23 men after acute myocardial infarction (AMI) with comorbid arterial hypertension (AH). Mean age of patients was 56.7 years. Recurrent myocardial infarction was determined in 38.4%, cardiac failure I-III functional classes--100% of the cases. All patients underwent clinical examination, electrocardiography and echocardiography, blood lipid profile. Standard comprehensive treatment for two years included an perindopril 5-10 mg/day, beta-blocker bisoprolol--5-10 mg/day, antisclerotic drug atorvastatin--20 mg/day and aspirin--75 mg/day. The patients after treatment was determined by a gradual increase towards the target of AT at 3, 6 and 12 to 24 months. Concentric left ventricular hypertrophy (LVH) before treatment was determined in 47.8%, eccentric--in 52.2% of patients. In the study of degrees of LVH I (initial) the extent to treatment was determined by 4.3%, II (moderate)--26.1%, III (large)--at 69.6%, indicating the development of cardiac remodeling. After the treatment was determined by marked reduction III (large) degree and transfer it in the II (moderate) and I (small) degree of left ventricular hypertrophy due to more or less pronounced changes remodeling left ventricular. The obtained data allow a more detailed and adequately assess the structural and functional outcome variables and determine the regression of myocardial hypertrophy in the background to achieve target blood pressure, which is important in practical cardiology.
2012-01-01
Background Cardiovascular magnetic resonance (CMR) is the gold standard non-invasive method for determining left ventricular (LV) mass and volume but has not been used previously to characterise the LV remodeling response in aortic stenosis. We sought to investigate the degree and patterns of hypertrophy in aortic stenosis using CMR. Methods Patients with moderate or severe aortic stenosis, normal coronary arteries and no other significant valve lesions or cardiomyopathy were scanned by CMR with valve severity assessed by planimetry and velocity mapping. The extent and patterns of hypertrophy were investigated using measurements of the LV mass index, indexed LV volumes and the LV mass/volume ratio. Asymmetric forms of remodeling and hypertrophy were defined by a regional wall thickening ≥13 mm and >1.5-fold the thickness of the opposing myocardial segment. Results Ninety-one patients (61±21 years; 57 male) with aortic stenosis (aortic valve area 0.93±0.32cm2) were recruited. The severity of aortic stenosis was unrelated to the degree (r2=0.012, P=0.43) and pattern (P=0.22) of hypertrophy. By univariate analysis, only male sex demonstrated an association with LV mass index (P=0.02). Six patterns of LV adaption were observed: normal ventricular geometry (n=11), concentric remodeling (n=11), asymmetric remodeling (n=11), concentric hypertrophy (n=34), asymmetric hypertrophy (n=14) and LV decompensation (n=10). Asymmetric patterns displayed considerable overlap in appearances (wall thickness 17±2mm) with hypertrophic cardiomyopathy. Conclusions We have demonstrated that in patients with moderate and severe aortic stenosis, the pattern of LV adaption and degree of hypertrophy do not closely correlate with the severity of valve narrowing and that asymmetric patterns of wall thickening are common. Trial registration ClinicalTrials.gov Reference Number: NCT00930735 PMID:22839417
Reid, Brian G.; Stratton, Matthew S.; Bowers, Samantha; Cavasin, Maria A.; Demos-Davies, Kimberley M.; Susano, Isidro; McKinsey, Timothy A.
2016-01-01
Chronic cardiac hypertrophy is maladaptive and contributes to the pathogenesis of heart failure. The objective of this study was to identify small molecule inhibitors of pathological cardiomyocyte hypertrophy. High content screening was performed with primary neonatal rat ventricular myocytes (NRVMs) cultured on 96-well plates and treated with a library of 3241 distinct small molecules. Non-toxic hit compounds that blocked hypertrophy in response to phenylephrine (PE) and phorbol myristate acetate (PMA) were identified based on their ability to reduce cell size and inhibit expression of atrial natriuretic factor (ANF), which is a biomarker of pathological cardiac hypertrophy. Many of the hit compounds are existing drugs that have not previously been evaluated for benefit in the setting of cardiovascular disease. One such compound, the anti-malarial drug artesunate, blocked left ventricular hypertrophy (LVH) and improved cardiac function in adult mice subjected to transverse aortic constriction (TAC). These findings demonstrate that phenotypic screening with primary cardiomyocytes can be used to discover anti-hypertrophic lead compounds for heart failure drug discovery. Using annotated libraries of compounds with known selectivity profiles, this screening methodology also facilitates chemical biological dissection of signaling networks that control pathological growth of the heart. PMID:27130278
Telmisartan regresses left ventricular hypertrophy in caveolin-1 deficient mice
Kreiger, Marta H; Di Lorenzo, Annarita; Teutsch, Christine; Kauser, Katalin; Sessa, William C.
2011-01-01
The role of angiotensin II (Ang II) in promoting cardiac hypertrophy is well known, however the role of the Ang II in a spontaneous model of hypertrophy in mice lacking the protein caveolin-1 (Cav- KO) has not been explored. In this study, WT and Cav-1 KO mice were treated with angiotensin receptor blocker (ARB), telmisartan, and cardiac function assessed by echocardiography. Treatment of Cav-1 KO mice with telmisartan significantly improved cardiac function compared to age-matched, vehicle treated Cav-1 KO mice, while telmisartan did not affected cardiac function in WT mice. Both left ventricular (LV) weight to body weight ratios and LV to tibial length ratios were also reverted by telmisartan in Cav-1 KO but not WT mice. LV hypertrophy was associated with increased expression of natriuretic peptides-A and –B, β-myosin heavy chain and TGF-β and telmisartan treatment normalized the expression of these genes. Telmisartan reduced the expression of collagen genes (Col1A and Col3A) and associated perivascular fibrosis in intramyocardial vessels in Cav-1 KO mice. In conclusion, telmisartan treatment reduces indexes of cardiac hypertrophy in this unique genetic model of spontaneous LV hypertrophy. PMID:20585312
Afzal, Muhammad R.; Samanta, Anweshan; Xuan, Yu-Ting; Girgis, Magdy; Elias, Harold K; Zhu, Yanqing; Davani, Arash; Yang, Yanjuan; Chen, Xing; Ye, Sheng; Wang, Ou-Li; Chen, Lei; Hauptman, Jeryl; Vincent, Robert J.; Dawn, Buddhadeb
2016-01-01
Rationale The role of interleukin (IL)-6 in the pathogenesis of cardiac myocyte hypertrophy remains controversial. Objective To conclusively determine whether IL-6 signaling is essential for the development of pressure overload-induced left ventricular (LV) hypertrophy, and to elucidate the underlying molecular pathways. Methods and Results Wild-type (WT) and IL-6 knockout (IL-6−/−) mice underwent sham surgery or transverse aortic constriction (TAC) to induce pressure overload. Serial echocardiograms and terminal hemodynamic studies revealed attenuated LV hypertrophy and superior preservation of LV function in IL-6−/− mice after TAC. The extents of LV remodeling, fibrosis, and apoptosis were reduced in IL-6−/− hearts after TAC. Transcriptional and protein assays of myocardial tissue identified CaMKII and STAT3 activation as important underlying mechanisms during cardiac hypertrophy induced by TAC. The involvement of these pathways in myocyte hypertrophy was verified in isolated cardiac myocytes from WT and IL-6−/− mice exposed to pro-hypertrophy agents. Furthermore, overexpression of CaMKII in H9c2 cells increased STAT3 phosphorylation, and exposure of H9c2 cells to IL-6 resulted in STAT3 activation that was attenuated by CaMKII inhibition. Together these results identify the importance of CaMKII-dependent activation of STAT3 during cardiac myocyte hypertrophy via IL-6 signaling. Conclusions Genetic deletion of IL-6 attenuates TAC-induced LV hypertrophy and dysfunction, indicating a critical role played by IL-6 in the pathogenesis of LV hypertrophy in response to pressure overload. CaMKII plays an important role in IL-6-induced STAT3 activation and consequent cardiac myocyte hypertrophy. These findings may have significant therapeutic implications for LV hypertrophy and failure in patients with hypertension. PMID:27126808
Klaus, D
1985-01-01
Left ventricular hypertrophy is the consequence of a structural adaptation of the heart in response to the chronic pressure load, leading to a reduction of the increased systolic wall stress. Studies in spontaneously hypertensive rats have shown, that left ventricular hypertrophy can be influenced by various, but not all antihypertensive agents. Alpha-methyldopa, captopril, beta-blockers and calcium channel blockers resulted in reversal of hypertrophy. Treatment with diuretics, hydralazine or minoxidil did not increase or alter degree of myocardial hypertrophy despite normalization of blood pressure. The biochemical profile after reversal of hypertrophy differs according to antihypertensive therapy, i.e. alpha-methyldopa induces an increase in collagen content, whereas captopril does not alter the collagen content of the myocardium. Adrenergic factors play an important role in modulating the response of the heart. In clinical studies the reduction in cardiac mass does not depend solely on the antihypertensive effect on blood pressure levels. There is only a weak correlation between decrease of left ventricular hypertrophy and fall of blood pressure level, as is shown in 12 patients with essential hypertension, treated with captopril over 6 months. The degree of regression of hypertrophy is influenced by stability of blood pressure control (diurnal variations and response to stress are more important than single casual values), neurohumoral response, presence of associated cardiac diseases, cause and severity of hypertension, genetic factors and age. We studied the regression of left ventricular hypertrophy by M-mode-echocardiography in 12 patients with mild or moderate essential hypertension during a 6-month therapy with captopril (50-75 mg p.d.) and hydrochlorothiazide (50 mg p.d.). In 11 of 12 patients captopril treatment resulted in a reduction of LV-mass of 30.9 +/- 15.1% and wall thickness. Peak systolic and endsystolic wall stress decreased significantly (-29.1% and -27.2%, resp.) after blood pressure reduction, but were still slightly elevated. Ejection fraction increased by 5.4% (p less than or equal to 0.05). 6 hypertensive patients treated for 6 months with metoprolol (150 mg p.d.) and hydrochlorothiazide (50 mg p.d.) do not show significant reduction of LV-mass (-6.5%). Peak and endsystolic wall stress were significantly reduced (-33.1% and -11.5%, resp.) as in captopril therapy. In 34 patients with severe hypertension treated with captopril, hydrochlorothiazide and metoprolol over 30 months, we observed a decline in the Sokolow-Lyon-Index from 4.8 +/- 1.1 mV to 3.8 +/- 0.5 mV after 6 months.(ABSTRACT TRUNCATED AT 400 WORDS)
2016-01-01
In part 1, we considered cytomolecular mechanisms underlying calcific aortic valve disease (CAVD), hemodynamics, and adaptive feedbacks controlling pathological left ventricular hypertrophy provoked by ensuing aortic valvular stenosis (AVS). In part 2, we survey diverse signal transduction pathways that precede cellular/molecular mechanisms controlling hypertrophic gene expression by activation of specific transcription factors that induce sarcomere replication in-parallel. Such signaling pathways represent potential targets for therapeutic intervention and prevention of decompensation/failure. Hypertrophy provoking signals, in the form of dynamic stresses and ligand/effector molecules that bind to specific receptors to initiate the hypertrophy, are transcribed across the sarcolemma by several second messengers. They comprise intricate feedback mechanisms involving gene network cascades, specific signaling molecules encompassing G protein-coupled receptors and mechanotransducers, and myocardial stresses. Future multidisciplinary studies will characterize the adaptive/maladaptive nature of the AVS-induced hypertrophy, its gender- and individual patient-dependent peculiarities, and its response to surgical/medical interventions. They will herald more effective, precision medicine treatments. PMID:27184804
Hypertrophic Cardiomyopathy: Clinical Update.
Geske, Jeffrey B; Ommen, Steve R; Gersh, Bernard J
2018-05-01
Hypertrophic cardiomyopathy (HCM) is the most common heritable cardiomyopathy, manifesting as left ventricular hypertrophy in the absence of a secondary cause. The genetic underpinnings of HCM arise largely from mutations of sarcomeric proteins; however, the specific underlying mutation often remains undetermined. Patient presentation is phenotypically diverse, ranging from asymptomatic to heart failure or sudden cardiac death. Left ventricular hypertrophy and abnormal ventricular configuration result in dynamic left ventricular outflow obstruction in most patients. The goal of therapeutic interventions is largely to reduce dynamic obstruction, with treatment modalities spanning lifestyle modifications, pharmacotherapies, and septal reduction therapies. A small subset of patients with HCM will experience sudden cardiac death, and risk stratification remains a clinical challenge. This paper presents a clinical update for diagnosis, family screening, clinical imaging, risk stratification, and management of symptoms in patients with HCM. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Kato, S.; Koide, M.; Cooper, G. 4th; Zile, M. R.
1996-01-01
It has been hypothesized that the changes in myocardial stiffness induced by chronic hemodynamic overloading are dependent on changes in the passive stiffness of the cardiac muscle cell (cardiocyte). However, no previous studies have examined the passive constitutive properties of cardiocytes isolated from animals with myocardial hypertrophy. Accordingly, changes in relative passive stiffness of cardiocytes isolated from animals with chronic pressure- or volume-overload hypertrophy were determined by examining the effects of anisosmotic stress on cardiocyte size. Anisosmotic stress was produced by altering superfusate osmolarity. Hypertrophied cardiocytes were enzymatically isolated from 16 adult cats with right ventricular (RV) pressure-overload hypertrophy induced by pulmonary artery banding (PAB) and from 6 adult cats with RV volume-overload hypertrophy induced by creating an atrial septal defect (ASD). Left ventricular (LV) cardiocytes from each cat served as nonhypertrophied, normally loaded, same-animal controls. Superfusate osmolarity was decreased from 305 +/- 3 to 135 +/- 5 mosM and increased to 645 +/- 4 mosM. During anisosmotic stress, there were no significant differences between hypertrophied RV and normal LV cardiocytes in pressure overload PAB cats with respect to percent change in cardiocyte area (47 +/- 2% in RV vs. 48 +/- 2% in LV), diameter (46 +/- 3% in RV vs. 48 +/- 2% in LV), or length (2.4 +/- 0.2% in RV vs. 2.0 +/- 0.3% in LV), or sarcomere length (1.5 +/- 0.1% in RV vs. 1.3 +/- 0.3% in LV). Likewise, there were no significant differences in cardiocyte strain between hypertrophied RV and normal LV cardiocytes from ASD cats. In conclusion, chronic pressure-overload hypertrophy and chronic volume-overload hypertrophy did not alter the cardiocyte response to anisosmotic stress. Thus chronic overload hypertrophy did not alter relative passive cardiocyte stiffness.
Lu, Zhongbing; Xu, Xin; Hu, Xinli; Zhu, Guangshuo; Zhang, Ping; van Deel, Elza D.; French, Joel P.; Fassett, John T.; Oury, Tim D.; Bache, Robert J.; Chen, Yingjie
2008-01-01
Extracellular superoxide dismutase (SOD) contributes only a small fraction to total SOD activity in the normal heart but is strategically located to scavenge free radicals in the extracellular compartment. To examine the physiological significance of extracellular SOD in the response of the heart to hemodynamic stress, we studied the effect of extracellular SOD deficiency on transverse aortic constriction (TAC)–induced left ventricular remodeling. Under unstressed conditions extracellular SOD deficiency had no effect on myocardial total SOD activity, the ratio of glutathione:glutathione disulfide, nitrotyrosine content, or superoxide anion production but resulted in small but significant increases in myocardial fibrosis and ventricular mass. In response to TAC for 6 weeks, extracellular SOD-deficient mice developed more severe left ventricular hypertrophy (heart weight increased 2.56-fold in extracellular SOD-deficient mice as compared with 1.99-fold in wild-type mice) and pulmonary congestion (lung weight increased 2.92-fold in extracellular SOD-deficient mice as compared with 1.84-fold in wild-type mice). Extracellular SOD-deficient mice also had more ventricular fibrosis, dilation, and a greater reduction of left ventricular fractional shortening and rate of pressure development after TAC. TAC resulted in greater increases of ventricular collagen I, collagen III, matrix metalloproteinase-2, matrix metalloproteinase-9, nitrotyrosine, and superoxide anion production. TAC also resulted in a greater decrease of the ratio of glutathione:glutathione disulfide in extracellular SOD-deficient mice. The finding that extracellular SOD deficiency had minimal impact on myocardial overall SOD activity but exacerbated TAC induced myocardial oxidative stress, hypertrophy, fibrosis, and dysfunction indicates that the distribution of extracellular SOD in the extracellular space is critically important in protecting the heart against pressure overload. PMID:17998475
DOE Office of Scientific and Technical Information (OSTI.GOV)
Newth, C.J.; Corey, M.L.; Fowler, R.S.
1981-01-01
The incidence of right ventricular hypertrophy in 32 patients with cystic fibrosis was studied using thallium 201 (TI-201) myocardial perfusion scans, and compared with other noninvasive techniques including electrocardiography, vectorcardiography, and M-mode echocardiography. The patients (mean age, 17.3 yr; range, 7 to 33) had a wide range of clinical and pulmonary abnormalities (mean Shwachman-Kulczycki score, 66.6). In the total study group, TI-201 scans, like the vectorcardiograms and the M-mode echocardiograms, gave a surprisingly high proportion of positive predictions for right ventricular hypertrophy (RVH) (44%). The correlations with all other noninvasive methods were uniformly poor, so caution must be exercised inmore » using this technique to predict early RVH in order to follow the natural history of cor pulmonale in cystic fibrosis. At the time of the study, 6 patients had clinical evidence of right ventricular failure, and in this disease setting must have had RVH. In 3 patients, RVH was confirmed at autopsy, and it was successfully predicted by TI-201 scans in 5 of the 6 patients. The false negative scan may have been due to regional myocardial ischemia secondary to severe right ventricular failure. In contrast, the vectorcardiogram, using Fowler's new criteria, made a successful prediction of RVH in all 6 patients, and the electro cardiogram in only 3. Although the M-mode echocardiogram was abnormal in all patients, it would have predicted RVH (with increased right ventricular anterior wall thickness) in only 1 patient. We concluded that TI-201 myocardial perfusion cans are good at confirming RVH in cases with established right ventricular failure, but have no advantage over vectorcardiographic assessments, which are logistically easier to perform and carry no radiation risks.« less
Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance.
Smedema, Jan-Peter; van Geuns, Robert-Jan; Ainslie, Gillian; Ector, Joris; Heidbuchel, Hein; Crijns, Harry J G M
2017-11-01
Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast-enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis. We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast-enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non-invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P < 0.001). Right ventricular enhancement correlated with systolic ventricular dysfunction (P < 0.001), hypertrophy (P = 0.001), and dilation (P < 0.001). Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.
Reader, J Rachel; Canfield, Don R; Lane, Jennifer F; Kanthaswamy, Sreetharan; Ardeshir, Amir; Allen, A Mark; Tarara, Ross P
2016-04-01
Necropsy records and associated clinical histories from the rhesus macaque colony at the California National Primate Research Center were reviewed to identify mortality related to cardiac abnormalities involving left ventricular hypertrophy (LVH). Over a 21-y period, 162 cases (female, 90; male, 72) of idiopathic LVH were identified. Macaques presented to necropsy with prominent concentric hypertrophy of the left ventricle associated with striking reduction of the ventricular lumen. Among all LVH cases, 74 macaques (female, 39; male, 35), mostly young adults, presented for spontaneous (sudden) death; more than 50% of these 74 cases were associated with a recent history of sedation or intraspecific aggression. The risk of sudden death in the 6- to 9-y-old age group was significantly higher in male macaques. Subtle histologic cardiac lesions included karyomegaly and increased cardiac myocyte diameter. Pedigree analyses based on rhesus macaque LVH probands suggested a strong genetic predisposition for the condition. In humans, hypertrophic cardiomyopathy (HCM) is defined by the presence of unexplained left ventricular hypertrophy, associated with diverse clinical outcomes ranging from asymptomatic disease to sudden death. Although the overall risk of disease complications such as sudden death, end-stage heart failure, and stroke is low (1% to 2%) in patients with HCM, the absolute risk can vary dramatically. Prima facie comparison of HCM and LVH suggest that further study may allow the development of spontaneously occurring LVH in rhesus macaques as a useful model of HCM, to better understand the pathogenesis of this remarkably heterogeneous disease.
Structural pathways and prevention of heart failure and sudden death.
Pacifico, Antonio; Henry, Philip D
2003-07-01
We review the macroscopic and microscopic anatomy of myocardial disease associated with heart failure (HF) and sudden cardiac death (SCD) and focus on the prevention of SCD in light of its structural pathways. Compared to patients without SCD, patients with SCD exhibit 5- to 6-fold increases in the risks of ventricular arrhythmias and SCD. Epidemiologically, left ventricular hypertrophy by ECG or echocardiography acts as a potent dose-dependent SCD predictor. Dyslipidemia, a coronary disease risk factor, independently predicts echocardiographic hypertrophy. In adult SCD autopsy studies, increases in heart weight and severe coronary disease are constant findings, whereas rates of acute coronary thrombi vary remarkably. The microscopic myocardial anatomy of SCD is incompletely defined but may include prevalent changes of advanced myocardial disease, including cardiomyocyte hypertrophy, cardiomyocyte apoptosis, fibroblast hyperplasia, diffuse and focal matrix protein accumulation, and recruitment of inflammatory cells. Hypertrophied cardiomyocytes express "fetospecific" genetic programs that can account for acquired long QT physiology with risk for polymorphic ventricular arrhythmias. Structural heart disease associated with HF and high SCD risk is causally related to an up-regulation of the adrenergic renin-angiotensin-aldosterone pathway. In outcome trials, suppression of this pathway with combinations of beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin-II receptor blockers, and mineralocorticoid receptor blockers have achieved substantial total mortality and SCD reductions. Contrarily, trials with ion channel-active agents that are not known to reduce structural heart disease have failed to reduce these risks. Device therapy effectively prevents SCD, but whether biventricular pacing-induced remodeling decreases left ventricular mass remains uncertain.
MacLea, H B; Boon, J A; Bright, J M
2013-01-01
Hypertrophic cardiomyopathy (HCM) is heterogeneous in both people and cats, with variability in the distribution of hypertrophy, hemodynamic characteristics, and Doppler echocardiographic findings. To document the Doppler echocardiographic characteristics of midventricular obstruction in some cats with HCM. Eight cats with hypertrophic cardiomyopathy. Retrospective case series. The medical records of cats presenting to the cardiology service at Colorado State University between February 2009 and January 2012 were reviewed. All cats had a physical examination; Doppler systolic blood pressure measurement; and transthoracic two-dimensional (2D), M-mode, and Doppler echocardiography were performed. A more thorough evaluation of the echocardiographic images and measurements was performed. Cats included in this study had echocardiograms of adequate quality to confirm the diagnosis of midventricular obstruction by documentation of left midventricular concentric hypertrophy; a midventricular turbulent Doppler color flow pattern; and high velocity, late-peaking flow at the area of turbulence. Cats with evidence of systemic hypertension defined as a systolic Doppler blood pressure of greater than 170 mmHg were excluded. All 8 cats had left ventricular hypertrophy at the level of the papillary muscles; left, midventricular hypertrophy; and in 4/8 cats there was apical hypertrophy or basilar hypertrophy of the interventricular septum. Color flow Doppler revealed turbulent flow in 8/8 cats and spectral Doppler (continuous and pulsed wave) revealed increased flow velocities and late-peaking flow profiles at the level of the left midventricle. Two of 8 cats had a bifid midventricular flow profile in which there was a midsystolic decline in left ventricular velocities with elevated velocities extending into early diastole. The peak left ventricular outflow velocity in all 8 cats was normal. A variant of HCM characterized by hypertrophy at the level of the papillary muscles with midventricular obstruction is present in some cats. Recognition of this variant of feline HCM allows identification of HCM in cats with murmurs where the more classic features of HCM are not present. Copyright © 2013 by the American College of Veterinary Internal Medicine.
Lu, Yi; Zhao, Ming; Liu, Jin-Jun; He, Xi; Yu, Xiao-Jiang; Liu, Long-Zhu; Sun, Lei; Chen, Li-Na; Zang, Wei-Jin
2017-09-01
Cardiac hypertrophy is associated with autonomic imbalance, characterized by enhanced sympathetic activity and withdrawal of parasympathetic control. Increased parasympathetic function improves ventricular performance. However, whether pyridostigmine, a reversible acetylcholinesterase inhibitor, can offset cardiac hypertrophy induced by pressure overload remains unclear. Hence, this study aimed to determine whether pyridostigmine can ameliorate pressure overload-induced cardiac hypertrophy and identify the underlying mechanisms. Rats were subjected to either sham or constriction of abdominal aorta surgery and treated with or without pyridostigmine for 8 weeks. Vagal activity and cardiac function were determined using PowerLab. Cardiac hypertrophy was evaluated using various histological stains. Protein markers for cardiac hypertrophy were quantitated by Western blot and immunoprecipitation. Pressure overload resulted in a marked reduction in vagal discharge and a profound increase in cardiac hypertrophy index and cardiac dysfunction. Pyridostigmine increased the acetylcholine levels by inhibiting acetylcholinesterase in rats with pressure overload. Pyridostigmine significantly attenuated cardiac hypertrophy based on reduction in left ventricular weight/body weight, suppression of the levels of atrial natriuretic peptide, brain natriuretic peptide and β-myosin heavy chain, and a reduction in cardiac fibrosis. These effects were accompanied by marked improvement of cardiac function. Additionally, pyridostigmine inhibited the CaN/NFAT3/GATA4 pathway and suppressed Orai1/STIM1 complex formation. In conclusion, pressure overload resulted in cardiac hypertrophy, cardiac dysfunction and a significant reduction in vagal discharge. Pyridostigmine attenuated cardiac hypertrophy and improved cardiac function, which was related to improved cholinergic transmission efficiency (decreased acetylcholinesterase and increased acetylcholine), inhibition of the CaN/NFAT3/GATA4 pathway and suppression of the interaction of Orai1/STIM1. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
Khangura, Jaspreet; Culleton, Bruce F; Manns, Braden J; Zhang, Jianguo; Barnieh, Lianne; Walsh, Michael; Klarenbach, Scott W; Tonelli, Marcello; Sarna, Magdalena; Hemmelgarn, Brenda R
2010-06-24
Left ventricular (LV) hypertrophy is common among patients on hemodialysis. While a relationship between blood pressure (BP) and LV hypertrophy has been established, it is unclear which BP measurement method is the strongest correlate of LV hypertrophy. We sought to determine agreement between various blood pressure measurement methods, as well as identify which method was the strongest correlate of LV hypertrophy among patients on hemodialysis. This was a post-hoc analysis of data from a randomized controlled trial. We evaluated the agreement between seven BP measurement methods: standardized measurement at baseline; single pre- and post-dialysis, as well as mean intra-dialytic measurement at baseline; and cumulative pre-, intra- and post-dialysis readings (an average of 12 monthly readings based on a single day per month). Agreement was assessed using Lin's concordance correlation coefficient (CCC) and the Bland Altman method. Association between BP measurement method and LV hypertrophy on baseline cardiac MRI was determined using receiver operating characteristic curves and area under the curve (AUC). Agreement between BP measurement methods in the 39 patients on hemodialysis varied considerably, from a CCC of 0.35 to 0.94, with overlapping 95% confidence intervals. Pre-dialysis measurements were the weakest predictors of LV hypertrophy while standardized, post- and inter-dialytic measurements had similar and strong (AUC 0.79 to 0.80) predictive power for LV hypertrophy. A single standardized BP has strong predictive power for LV hypertrophy and performs just as well as more resource intensive cumulative measurements, whereas pre-dialysis blood pressure measurements have the weakest predictive power for LV hypertrophy. Current guidelines, which recommend using pre-dialysis measurements, should be revisited to confirm these results.
Enhanced functional expression of transient outward current in hypertrophied feline myocytes.
Ten Eick, R E; Zhang, K; Harvey, R D; Bassett, A L
1993-08-01
Cardiac hypertrophy can decrease myocardial contractility and alter the electrophysiological activity of the heart. It is well documented that action potentials recorded from hypertrophied feline ventricular cells can exhibit depressed plateau voltages and prolonged durations. Similar findings have been made by others in rabbit, rat, guinea pig, and human heart. Whole-cell patch voltage-clamp studies designed to explain these changes in the action potential suggest that the only component of the membrane current recorded from feline right ventricular (RV) myocytes found to be substantially different from normal is the 4-amino-pyridine-sensitive transient outward current (I(to)). However, it was not clear if the change in I(to) could explain the changes in the action potential of hypertrophied cardiocytes, nor was it clear if these changes reflect an alteration in the electrophysiological character of the channels underlying I(to). A kinetic comparison of I(to) elicited by hypertrophied RV myocytes with that elicited by comparable normal RV myocytes previously revealed no differences, suggesting that the increased magnitude of the peak I(to) recorded from hypertrophied myocytes arises because the current density increases and not because of any alteration in the kinetic parameters governing the current. This finding suggests that in hypertrophy additional normal channels are expressed rather than a kinetically different channel subtype emerging. Investigations designed to determine if enhancement of I(to) could explain the hypertrophy-induced changes in plateau voltage and action potential duration suggest that a change in I(to) density can indeed explain the entire effect of hypertrophy on RV action potentials. If this notion is correct, the likelihood of "sudden death" in patients with myocardial hypertrophy might be decreased by a blocker selective for cardiac I(to).
Fuster, Rafael García; Montero Argudo, José A; Albarova, Oscar Gil; Hornero Sos, Fernando; Cánovas López, Sergio; Bueno Codoñer, María; Buendía Miñano, José A; Rodríguez Albarran, Ignacio
2005-06-01
Ventricular dysfunction and high hypertrophy may influence surgical outcome in aortic stenosis. Our aim was to determine whether an excessive left ventricular mass index (LVMI) discriminates different risk profiles in aortic stenosis with low ventricular ejection fraction (LVEF). Three hundred and thirty-nine patients with severe aortic stenosis underwent valve replacement (Mar-1994 and Nov-2001). LVMI values over the superior quartile were considered increased. Mortality models were constructed in global and LVEF
VALSARTAN REGULATES MYOCARDIAL AUTOPHAGY AND MITOCHONDRIAL TURNOVER IN EXPERIMENTAL HYPERTENSION
Zhang, Xin; Li, Zi-Lun; Crane, John A.; Jordan, Kyra L.; Pawar, Aditya S.; Textor, Stephen C.; Lerman, Amir; Lerman, Lilach O.
2014-01-01
Renovascular hypertension alters cardiac structure and function. Autophagy is activated during left ventricular hypertrophy and linked to adverse cardiac function. The Angiotensin II receptor blocker Valsartan lowers blood pressure and is cardioprotective, but whether it modulates autophagy in the myocardium is unclear. We hypothesized that Valsartan would alleviate autophagy and improve left ventricular myocardial mitochondrial turnover in swine renovascular hypertension. Domestic pigs were randomized to control, unilateral renovascular hypertension, and renovascular hypertension treated with Valsartan (320 mg/day) or conventional triple therapy (Reserpine+hydralazine+hydrochlorothiazide) for 4 weeks post 6-weeks of renovascular hypertension (n=7 each group). Left ventricular remodeling, function and myocardial oxygenation and microcirculation were assessed by multi-detector computer tomography, blood-oxygen-level-dependent magnetic resonance imaging and microcomputer tomography. Myocardial autophagy, markers for mitochondrial degradation and biogenesis, and mitochondrial respiratory-chain proteins were examined ex vivo. Renovascular hypertension induced left ventricular hypertrophy and myocardial hypoxia, enhanced cellular autophagy and mitochondrial degradation, and suppressed mitochondrial biogenesis. Valsartan and triple therapy similarly decreased blood pressure, but Valsartan solely alleviated left ventricular hypertrophy, ameliorated myocardial autophagy and mitophagy, and increased mitochondrial biogenesis. In contrast, triple therapy only slightly attenuated autophagy and preserved mitochondrial proteins, but elicited no improvement in mitophagy. These data suggest a novel potential role of Valsartan in modulating myocardial autophagy and mitochondrial turnover in renovascular hypertension-induced hypertensive heart disease, which may possibly bolster cardiac repair via a blood pressure-independent manner. PMID:24752430
Periodontitis and myocardial hypertrophy.
Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei
2017-04-01
There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.
Hamela-Olkowska, Anita; Szymkiewicz-Dangel, Joanna; Własienko, Paweł; Majewska, Urszula; Bokiniec, Renata
2012-02-01
The use of fenoterol in the treatment of preterm labor is associated with the risk of many complications in the mother and the fetus. We present a case of a multipara treated with oral fenoterol due to threatening preterm labor 14 weeks. At 35 weeks of gestation the fetus was diagnosed with hypertrophic cardiomyopathy with severe impairment of the right ventricle. The only factor that might have caused such a state of the fetal circulatory system was fenoterol, used from 21 weeks of gestation. After the withdrawal of the fenoterol the fetal right ventricular function improved gradually. However fetal cardiac hypertrophy persisted until the birth at 39 weeks of gestation. Concentric hypertrophy of the right ventricular wall and interventricular septum were confirmed in the newborn.
Yu, Yihui; Hu, Zuoying; Li, Bing; Wang, Zhimei; Chen, Shaoliang
2018-05-22
This study aimed to investigate the effects and molecular mechanisms of ivabradine in preventing cardiac hypertrophy in an established transverse aortic constriction (TAC) mouse model. A total of 56 male C57BL/6 mice were randomly assigned into the following seven groups (8 mice per group): sham, TAC model, Iva-10 (10 mg/kg/day ivabradine), Iva-20 (20 mg/kg/day ivabradine), Iva-40 (40 mg/kg/day ivabradine), Iva-80 (80 mg/kg/day ivabradine), and Rap (rapamycin, a positive control). Echocardiography and left ventricular hemodynamics were performed. Hematoxylin-eosin (H&E), Masson's trichome staining, and TUNEL assays were conducted to evaluate cardiac hypertrophy, fibrosis, and apoptosis, respectively. Western blotting was performed to detect the expression of proteins related to the PI3K/Akt/mTOR/p70S6K pathway. Ivabradine could effectively improve left ventricular dysfunction and hypertrophy induced by TAC in a dose-independent manner. Moreover, no obvious change in heart rate (HR) was observed in the TAC and Rap groups, whereas a significant decrease in HR was found after ivabradine treatment (P < 0.05). Cardiac hypertrophy, fibrosis, and apoptosis induced by TAC were notably suppressed after either rapamycin or ivabradine treatment (P < 0.05). Ivabradine and rapamycin also decreased the expression of PI3K/Akt and mTOR induced by TAC. Ivabradine improved cardiac hypertrophy and fibrosis as well as reduced cardiomyocyte apoptosis via the PI3K/Akt/mTOR/p70S6K pathway in TAC model mice.
Molina, L; Elosua, R; Marrugat, J; Pons, S
1999-10-15
The relation between maximum systolic blood pressure (BP) during exercise and left ventricular (LV) mass is controversial. Physical activity also induces LV mass increase. The objective was to assess the relation between BP response to exercise and LV mass in normotensive men, taking into account physical activity practice. A cross-sectional study was performed. Three hundred eighteen healthy normotensive men, aged between 20 and 60 years, participated in this study. The Minnesota questionnaire was used to assess physical activity practice. An echocardiogram and a maximum exercise test were performed. LV mass was calculated and indexed to body surface area. LV hypertrophy was defined as a ventricular mass index > or =134 g/m2. BP was measured at the moment of maximum effort. Hypertensive response was considered when BP was > or =210 mm Hg. In the multiple linear regression model, maximum systolic BP was associated with LV mass index and correlation coefficient was 0.27 (SE 0.07). Physical activity practice and age were also associated with LV mass. An association between hypertensive response to exercise and LV hypertrophy was observed (odds ratio 3.16). Thus, BP response to exercise is associated with LV mass and men with systolic BP response > or =210 mm Hg present a 3-times higher risk of LV hypertrophy than those not reaching this limit. Physical activity practice is related to LV mass, but not to LV hypertrophy.
Atypical patterns of cardiac involvement in Fabry disease.
Coughlan, J J; Elkholy, K; O'Brien, J; Kiernan, T
2016-03-17
A 58-year-old woman was referred to our cardiology service with chest pain, exertional dyspnoea and palpitations on a background of known Fabry disease diagnosed with genetic testing in 1994. ECG showed sinus rhythm, shortened PR interval, widespread t wave inversion, q waves in the lateral leads and left ventricular hypertrophy (LVH). Coronary angiogram showed only mild atheroma. Transthoracic echocardiogram showed anterolateral LVH and reduced left ventricular cavity size in keeping with Fabry cardiomyopathy. Cardiac MRI demonstrated asymmetric hypertrophy with evidence of diffuse myocardial fibrosis in the maximally hypertrophied segments from base to apex with late gadolinium enhancement in the anterior and anteroseptal walls. This was quite an atypical appearance for Fabry cardiomyopathy. This case highlights the heterogeneity of patterns of cardiac involvement that may be associated with this rare X-linked lysosomal disorder. 2016 BMJ Publishing Group Ltd.
Patient-prosthesis mismatch in aortic valve replacement: really tolerable?
Fuster, Rafael García; Montero Argudo, José A; Albarova, Oscar Gil; Sos, Fernando Hornero; López, Sergio Cánovas; Codoñer, María Bueno; Buendía Miñano, José A; Albarran, Ignacio Rodríguez
2005-03-01
Several studies have demonstrated favorable results despite patient-prosthesis mismatch after aortic valve replacement with the use of third generation prostheses. Our aim was to determine whether this mismatch is always tolerable. A clinical-echocardiographic study has been performed in 339 consecutive patients who underwent aortic valve replacement because of aortic stenosis. In-hospital outcome and left ventricular mass index regression (1st month-1st year) were analyzed in the presence or absence of mismatch (indexed effective orifice area < or =0.85cm(2)/m(2)). The influence of high degrees of preoperative left ventricular mass on in-hospital mortality has also been evaluated. Left ventricular mass index was considered increased if the calculated value was over the superior quartile of the frequency distribution of all the values observed in both sexes. Mismatch was found in 38% of the patients. In the absence of mismatch, the absolute mass regression was proportional to the preoperative left ventricular mass. This regression was higher in patients with increased left ventricular mass indexed (vs not increased): -38.0+/-7.8 vs -8.8+/-4.7g/m(2), p<0.01 (1st month) and -67.7+/-16.9vs -23.5+/-6.7g/m(2), p<0.05 (1st year). Mass regression was impaired in the presence of mismatch, particularly, in patients with previously increased left ventricular mass: -8.2+/-11.6 vs -5.6+/-6.3g/m(2) (p=0.83) and -24.6+/-12.6 vs -11.7+/-10.5g/m(2) (p=0.54). This worse regression was reflected on a 100% incidence of residual hypertrophy at follow-up (1st month-1st year). In the presence of mismatch, increased ventricular mass was associated with higher mortality: 14.7% vs 2.1% (p<0.01). In the absence of mismatch, ventricular mass was not associated with mortality: 4.1 vs 2.5% (p=0.55). In patients with severe ventricular hypertrophy it may be important to elude patient-prosthesis mismatch to avoid a significant increase in mortality and improve ventricular mass regression. Mismatch may be tolerable in those patients with lesser degree of hypertrophy.
Broyd, Christopher J; Rigo, Fausto; Nijjer, Sukhjinder; Sen, Sayan; Petraco, Ricardo; Al-Lamee, Rasha; Foin, Nicolas; Chukwuemeka, Andrew; Anderson, Jon; Parker, Jessica; Malik, Iqbal S; Mikhail, Ghada W; Francis, Darrel P; Parker, Kim; Hughes, Alun D; Mayet, Jamil; Davies, Justin E
2018-06-23
Severe aortic stenosis frequently involves the development of left ventricular hypertrophy (LVH) creating a dichotomous hemodynamic state within the coronary circulation. Whilst the increased force of ventricular contraction enhances its resultant relaxation and thus increases the distal diastolic coronary 'suction' force, the presence of LVH has a potentially opposing effect on ventricular-coronary interplay. The aim of this study was to use non-invasive coronary wave-intensity analysis (WIA) to separate and measure the sequential effects of outflow-tract obstruction relief and then left ventricular hypertrophy (LVH) regression following intervention for aortic stenosis. 15 patients with unobstructed coronary arteries undergoing aortic valve intervention (11 SAVR, 4 TAVI) were successfully assessed before and after intervention, and at 6- and 12-months post-procedure. Coronary WIA was constructed from simultaneously acquired coronary flow from transthoracic echo and pressure from an oscillometric brachial-cuff system. Immediately following intervention, a decline in the BDW was noted (9.7±5.7 vs 5.1±3.6 x10 3 Wm -2 s -1 , p<0.01). Over 12 months, LV mass-index fell from 114±19 to 82±17 kg/m 2 . Accompanying this, the BDW fraction increased to 32.8±7.2% (p=0.01 vs post-procedure) and to 34.7±6.7% at 12 months (p<0.001 vs post-procedure). In aortic stenosis, both the outflow-tract gradient and the presence of LVH impact significantly on coronary haemodynamics that cannot be appreciated by examining resting coronary flow rates alone. An immediate change in coronary wave-intensity occurs following intervention with further effects appreciable with hypertrophy regression. The improvement in prognosis with treatment is likely to be attributable to both features. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
The impact of the metabolic syndrome on the outcome after aortic valve replacement.
Tadic, Marijana; Vukadinovic, Davor; Cvijanovic, Dane; Celic, Vera; Kocica, Mladen; Putnik, Svetozar; Ivanovic, Branislava
2014-10-01
The aim of this study was to examine the influence of the metabolic syndrome on the left ventricular geometry as well as on the early and mid-time outcome in patients with aortic stenosis who underwent aortic valve replacement. The study included 182 patients who underwent aortic valve replacement due to aortic stenosis. The metabolic syndrome was defined by the presence of at least three AHA-NHLB (American Heart Association/National Heart, Lung and Blood Institute) criteria. All the patients were followed for at least 2 years after the surgery. The metabolic syndrome did not influence the severity of aortic stenosis (mean gradient and aortic valve area). However, the metabolic syndrome was associated with the reduced prevalence of the normal left ventricular geometry and the increased risk of concentric left ventricular hypertrophy in patients with aortic stenosis. Among the metabolic syndrome criteria, only increased blood pressure was simultaneously associated with the short-term and mid-term outcome, independently of other risk factors. Increased fasting glucose level was an independent predictor of the only 30-day outcome after the valve replacement. The metabolic syndrome and left ventricular hypertrophy were, independently of hypertension and diabetes, associated with the 30-day outcome, as well as incidence of major cerebrovascular and cardiovascular events in the 2-year postoperative period. The metabolic syndrome does not change severity of the aortic stenosis, but significantly impacts the left ventricular remodeling in these patients. The metabolic syndrome and left ventricular hypertrophy, irrespective of hypertension and diabetes, are predictors of the short-term and mid-term outcome of patients with aortic stenosis who underwent aortic valve replacement.
Choline Protects Against Cardiac Hypertrophy Induced by Increased After-load
Zhao, Yilei; Wang, Chen; Wu, Jianwei; Wang, Yan; Zhu, Wenliang; Zhang, Yong; Du, Zhimin
2013-01-01
Background: Although inadequate intake of essential nutrient choline has been known to significantly increase cardiovascular risk, whether additional supplement of choline offering a protection against cardiac hypertrophy remain unstudied. Methods: The effects of choline supplements on pathological cardiac hypertrophic growth induced by transverse aorta constriction (TAC) for three weeks and cardiomyocyte hypertrophy in cultured cells induced by isoproterenol (ISO) 10 μM for 48 h stimulation were investigated. Western blot analysis and real-time PCR were used to determine the expression of ANP, BNP, β-MHC, miR-133a and Calcineurin. Results: Administration of 14 mg/kg choline to mice undergone TAC effectively attenuated the cardiac hypertrophic responses, as indicated by the reduced heart weight, left ventricular weight, ventricular thickness, and reduced expression of biomarker genes of cardiac hypertrophy. This anti-hypertrophic efficacy was reproduced in a cellular model of cardiomyocyte hypertrophy induced by isoproterenol in cultured neonatal cardiomyocytes. Our results further showed that choline rescued the aberrant downregulation of the muscle-specific microRNA miR-133a expression, a recently identified anti-hypertrophic factor, and restored the elevated calcineurin protein level, the key signaling molecule for the development of cardiac hypertrophy. These effects of choline were abolished by the M3 mAChR-specific antagonist 4-DAMP. Conclusion: Our study unraveled for the first time the cardioprotection of choline against cardiac hypertrophy, with correction of expression of miR-133a and calcineurin as a possible mechanism. Our findings suggest that choline supplement may be considered for adjunct anti-hypertrophy therapy. PMID:23493786
Zimarino, Marco; Montebello, Elena; Radico, Francesco; Gallina, Sabina; Perfetti, Matteo; Iachini Bellisarii, Francesco; Severi, Silva; Limbruno, Ugo; Emdin, Michele; De Caterina, Raffaele
2016-10-01
The exercise electrocardiographic stress test (ExET) is the most widely used non-invasive diagnostic method to detect coronary artery disease. However, the sole ST depression criteria (ST-max) have poor specificity for coronary artery disease in patients with left ventricular hypertrophy. We hypothesised that ST-segment depression/heart rate hysteresis, depicting the relative behaviour of ST segment depression during the exercise and recovery phase of the test might increase the diagnostic accuracy of ExET for coronary artery disease detection in such patients. In three cardiology centres, we studied 113 consecutive patients (mean age 66 ± 2 years; 88% men) with hypertension-related left ventricular hypertrophy at echocardiography, referred to coronary angiography after an ExET. The following ExET criteria were analysed: ST-max, chronotropic index, heart rate recovery, Duke treadmill score, ST-segment depression/heart rate hysteresis. We detected significant coronary artery disease at coronary angiography in 61 patients (53%). At receiver-operating characteristic analysis, ST-segment depression/heart rate hysteresis had the highest area under the curve value (0.75, P < 0.001 when compared with the 'neutral' receiver-operating characteristic curve value of 0.5). Area under the curve values were 0.68 (P < 0.01) for the chronotropic index, 0.58 (P = NS) for heart rate recovery, 0.57 (P = NS) for ST-max and 0.52 (P = NS) for the Duke treadmill score. Among currently available ExET diagnostic variables, ST-segment depression/heart rate hysteresis offers a substantially better diagnostic accuracy for coronary artery disease than conventional criteria in patients with hypertension-related left ventricular hypertrophy. © The European Society of Cardiology 2016.
Karamanlidis, Georgios; Bautista-Hernandez, Victor; Fynn-Thompson, Francis; Nido, Pedro del; Tian, Rong
2011-01-01
Background The outcome of the surgical repair in congenital heart disease (CHD) correlates with the degree of myocardial damage. In this study we determined whether mitochondrial DNA depletion is a sensitive marker of right ventricular (RV) damage and whether impaired mitochondrial DNA (mtDNA) replication contributes to the transition from compensated hypertrophy to failure. Methods and Results RV samples obtained from 31 patients undergoing cardiac surgery were compared to 5 RV samples from non-failing hearts (control). Patients were divided into compensated hypertrophy and failure groups based on preoperative echocardiography, catheterization and/or MRI data. Mitochondrial enzyme activities (citrate synthase and succinate dehydrogenase) were maintained during hypertrophy and decreased by ~40% (p<0.05 vs. control) at the stage of failure. In contrast, mtDNA content was progressively decreased in the hypertrophied RV through failure (by 28±8% and 67±11% respectively, p<0.05 for both), whereas mtDNA encoded gene expression was sustained by increased transcriptional activity during compensated hypertrophy but not in failure. MtDNA depletion was attributed to reduced mtDNA replication in both hypertrophied and failing RV and it was independent of PGC-1 down-regulation but was accompanied by reduced expression of proteins constituting the mtDNA replication fork. Decreased mtDNA content in compensated hypertrophy was also associated with pathological changes of mitochondria ultrastructure. Conclusions Impaired mtDNA replication causes early and progressive depletion of mtDNA in the RV of the CHD patients during the transition from hypertrophy to failure. Decreased mtDNA content is likely a sensitive marker of mitochondrial injury in this patient population. PMID:21840936
Kruppel-Like Factor 15 Is Critical for the Development of Left Ventricular Hypertrophy.
Patel, Sheila K; Ramchand, Jay; Crocitti, Vincenzo; Burrell, Louise M
2018-04-27
Left ventricular hypertrophy (LVH) is an independent risk factor for adverse cardiovascular events and is often present in patients with hypertension. Treatment to reduce blood pressure and regress LVH is key to improving health outcomes, but currently available drugs have only modest cardioprotective effects. Improved understanding of the molecular mechanisms involved in the development of LVH may lead to new therapeutic targets in the future. There is now compelling evidence that the transcription factor Kruppel-like factor 15 (KLF15) is an important negative regulator of cardiac hypertrophy in both experimental models and in man. Studies have reported that loss or suppression of KLF15 contributes to LVH, through lack of inhibition of pro-hypertrophic transcription factors and stimulation of trophic and fibrotic signaling pathways. This review provides a summary of the experimental and human studies that have investigated the role of KLF15 in the development of cardiac hypertrophy. It also discusses our recent paper that described the contribution of genetic variants in KLF15 to the development of LVH and heart failure in high-risk patients.
dos Santos Moreira, Carlos; Serejo, Fátima; Alcântara, Paula; Ramalhinho, Vítor; Braz Nogueira, J
2015-05-01
An exaggerated accumulation of type I and type III fibrillar collagens occurs throughout the free wall and interventricular septum of patients with primary hypertension and left ventricular hypertrophy (LVH). In the present study the serum concentration of procollagen type III amino terminal peptide (PIIIP) was measured to determine the value of this peptide as a potential marker of ventricular fibrosis in hypertensive patients, particularly those with LVH. The study population consisted of patients with never-treated mild to moderate essential hypertension and 30 normotensive control subjects. Clinical, echocardiographic, electrocardiographic and biochemical parameters were assessed in all patients. Heart rate, body mass index and levels of blood pressure were increased in hypertensives, particularly those with LVH, compared to normotensive controls. Posterior wall thickness, left ventricular (LV) mass and LV mass index, and serum PIIIP concentration were also increased in hypertensives, with significant differences between the two hypertensive groups. The ratio between maximal early and late transmitral flow velocity measured during diastole was lower in hypertensives, particularly those with LVH, than in normotensive controls. The increase in PIIIP indicates that type III collagen synthesis increases in hypertensives, particularly those with LVH, implying that alterations in the heart in hypertension are the result not solely of hypertrophied LV muscle, but also of increased collagen deposition within the ventricular wall and around the coronary vessels. Thus, measurement of serum PIIIP could be a practical and useful tool in the non-invasive assessment of myocardial remodeling in hypertension. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.
Nassar, Seham Zakaria; Hassaan, Passainte S; Abdelmonsif, Doaa A; ElAchy, Samar Nabil
2018-05-15
Cerium oxide nanoparticles (CeO 2 NPs) have been recently introduced into the medical field for their antioxidant properties. The ability of CeO 2 NPs alone or in combination with spironolactone (SP) to attenuate monocrotaline (MCT)-induced pulmonary hypertension and associated right ventricular hypertrophy was studied in rats. A special emphasis was given to endothelin-1 pathway. Pulmonary hypertension was induced in albino rats by a single subcutaneous injection of MCT (60 mg/kg). Rats received either single CeO 2 NPs therapy or combined therapy with SP for 2 weeks. CeO 2 NPs improved pulmonary function tests with concomitant decrease in serum endothelin-1 and pulmonary expression of endothelin-1 and its receptor ETAR. Besides, CeO 2 NPs diminished MCT-induced right ventricular hypertrophy and reduced cardiac oxidative stress and apoptosis. CeO 2 NPs could improve pulmonary hypertension and associated right ventricular hypertrophy with no additive value for SP. Besides being an antioxidant, CeO 2 NPs work through endothelin-1 pathway to improve pulmonary hypertension. Copyright © 2018 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Koide, M.; Hamawaki, M.; Narishige, T.; Sato, H.; Nemoto, S.; DeFreyte, G.; Zile, M. R.; Cooper G, I. V.; Carabello, B. A.
2000-01-01
BACKGROUND: Because initially compensatory myocardial hypertrophy in response to pressure overloading may eventually decompensate to myocardial failure, mechanisms responsible for this transition have long been sought. One such mechanism established in vitro is densification of the cellular microtubule network, which imposes a viscous load that inhibits cardiocyte contraction. METHODS AND RESULTS: In the present study, we extended this in vitro finding to the in vivo level and tested the hypothesis that this cytoskeletal abnormality is important in the in vivo contractile dysfunction that occurs in experimental aortic stenosis in the adult dog. In 8 dogs in which gradual stenosis of the ascending aorta had caused severe left ventricular (LV) pressure overloading (gradient, 152+/-16 mm Hg) with contractile dysfunction, LV function was measured at baseline and 1 hour after the intravenous administration of colchicine. Cardiocytes obtained by biopsy before and after in vivo colchicine administration were examined in tandem. Microtubule depolymerization restored LV contractile function both in vivo and in vitro. CONCLUSIONS: These and additional corroborative data show that increased cardiocyte microtubule network density is an important mechanism for the ventricular contractile dysfunction that develops in large mammals with adult-onset pressure-overload-induced cardiac hypertrophy.
Takashi, Yuichi; Kinoshita, Yuka; Hori, Michiko; Ito, Nobuaki; Taguchi, Manabu; Fukumoto, Seiji
2017-05-01
Fibroblast growth factor 23 (FGF23) is a hormone regulating phosphate metabolism. Excessive actions of FGF23 cause several types of FGF23-related hypophosphatemic rickets/osteomalacia. Recently, it was reported that FGF23 levels were independently correlated with left ventricular hypertrophy (LVH) in patients with chronic kidney disease (CKD). In addition, FGF23 was also shown to cause cardiac hypertrophy directly acting on cardiomyocytes. However, there is no study indicating the correlation between FGF23 and LVH in adult patients with FGF23-related hypophosphatemic rickets/osteomalacia. Therefore, we examined the existence of LVH in these patients. We recruited consecutive 24 patients with FGF23-related hypophosphatemic diseases. Their serum intact FGF23 levels and the parameters associated with LVH, including left ventricular mass index (LVMI), relative wall thickness (RWT), Sokolow-Lyon voltage, and Cornell product, were measured. The correlations between FGF23 and these parameters were examined. The participants did not show LVH on the whole. In addition, no significant correlation was observed by these examinations. It seems unlikely that FGF23 levels are the apparent determinant of the cardiac mass in patients with FGF23-related hypophosphatemic rickets/osteomalacia.
Minoxidil accelerates heart failure development in rats with ascending aortic constriction.
Turcani, M; Jacob, R
1998-06-01
To test the ability of the heart to express characteristic geometric features of concentric and eccentric hypertrophy concurrently, constriction of the ascending aorta was performed in 4-week-old rats. Simultaneously, these rats were treated with an arteriolar dilator minoxidil. An examination 6 weeks after induction of the hemodynamic overload revealed no signs of congestion in systemic or pulmonary circulation in rats with aortic constriction or minoxidil-treated sham-operated rats. The magnitude of hemodynamic overload caused by aortic constriction or minoxidil treatment could be considered as equivalent, because the same enlargement of left ventricular pressure-volume area was necessary to compensate for either pressure or volume overload. Myocardial contractility decreased in rats with aortic constriction, and the compensation was achieved wholly by the marked concentric hypertrophy. Volume overload in minoxidil-treated rats was compensated partially by the eccentric hypertrophy and partially by the increased myocardial contractility. In contrast, increased lung weight and pleural effusion were found in all minoxidil-treated rats with aortic constriction. Unfavorable changes in left ventricular mass and geometry, relatively high chamber stiffness, and depressed ventricular and myocardial function were responsible for the massive pulmonary congestion.
Tao, Wen; Shi, Jianjian; Dorn, Gerald W.; Wei, Lei; Rubart, Michael
2012-01-01
Pathological left ventricular hypertrophy (LVH) is consistently associated with prolongation of the ventricular action potentials. A number of previous studies, employing various experimental models of hypertrophy, have revealed marked differences in the effects of hypertrophy on action potential duration (APD) between myocytes from endocardial and epicardial layers of the LV free wall. It is not known, however, whether pathological LVH is also accompanied by redistribution of APD among myocytes from the same layer in the LV free wall. In the experiments here, LV epicardial action potential remodeling was examined in a mouse model of decompensated LVH, produced by cardiac-restricted transgenic Gαq overexpression. Confocal linescanning-based optical recordings of propagated action potentials from individual in situ cardiomyocytes across the outer layer of the anterior LV epicardium demonstrated spatially non-uniform action potential prolongation in transgenic hearts, giving rise to alterations in spatial dispersion of epicardial repolarization. Local density and distribution of anti-Cx43 mmune reactivity in Gαq hearts were unchanged compared to wild-type hearts, suggesting preservation of intercellular coupling. Confocal microscopy also revealed heterogeneous disorganization of T-tubules in epicardial cardiomyocytes in situ. These data provide evidence of the existence of significant electrical and structural heterogeneity within the LV epicardial layer of hearts with transgenic Gαq overexpression-induced hypertrophy, and further support the notion that a small portion of electrically well connected LV tissue can maintain dispersion of action potential duration through heterogeneity in the activities of sarcolemmal ionic currents that control repolarization. It remains to be examined whether other experimental models of pathological LVH, including pressure overload LVH, similarly exhibit alterations in T-tubule organization and/or dispersion of repolarization within distinct layers of LV myocardium. PMID:22728217
Jaroch, Joanna; Łoboz-Grudzień, Krystyna; Magda, Stefania; Florescu, Maria; Bociąga, Zbigniew; Ciobanu, Andrea O; Kruszyńska, Ewa; Dudek, Krzysztof; Vinereanu, Dragos
2016-01-01
Left ventricular hypertrophy (LVH) and geometry patterns vary in different hemodynamic profiles The concentric hypertrophy (CH) pattern has been proved to have the worst prognosis. The aim of the study was to test the hypothesis that carotid artery stiffness, as a marker of vascular damage, is associated with CH, independently of other potential determinants such as demographic factors (age, sex, BMI), clinical parameters (smoking, diabetes, creatinine level) and hemodynamic variables (blood pressure, pulse pressure [PP]). The study involved 262 subjects (89 men): 202 patients with hypertension (153 untreated, 49 on medication), aged 55.7 ± 10 years, and 60 age-matched normal controls. The subjects were examined by echocardiography and carotid ultrasound with a high-resolution echo-tracking system. Based on the left ventricular mass index (LVMI) and relative wall thickness (RWT), the patients with hypertension were divided into four patterns of LVH and geometry: normal geometry (N, n = 57), concentric remodeling (CR, n = 48), concentric hypertrophy CH (n = 62) and eccentric hypertrophy (EH, n = 35). Intima-media thickness (IMT) and the parameters of arterial stiffness were also assessed using the β stiffness index (β), Young elastic modulus (Ep), arterial compliance (AC), one-point pulse wave velocity (PWVβ) and the wave reflection augmentation index (AI). Univariate analysis showed that the following variables are significant in determining CH: β > 8.4, Ep > 136 kPa, PWVβ > 7.1 m/s, AI > 21.9%, systolic BP > 151 mm Hg, PP > 54, IMT > 0.56 and the presence of diabetes. However, by multivariate analysis only AI (OR 3.65, p = 0.003), PWVβ > 7.1 m/s (OR 2.86, p = 0.014), systolic BP (OR 3.12, p = 0037) and the presence of diabetes (OR 3.75, p = 0.007) were associated independently with the occurrence of CH. Concentric hypertrophy in hypertension is strongly associated with carotid arterial stiffness and wave reflection parameters, independently of the influence of systolic blood pressure and diabetes.
Biederman, Robert W W; Doyle, Mark; Young, Alistair A; Devereux, Richard B; Kortright, Eduardo; Perry, Gilbert; Bella, Jonathan N; Oparil, Suzanne; Calhoun, David; Pohost, Gerald M; Dell'Italia, Louis J
2008-08-01
Concentric hypertensive left ventricular (LV) hypertrophy is presumed to be a symmetrical process. Using MRI-derived intramyocardial strain, we sought to determine whether segmental deformation was also symmetrical, as suggested by echocardiography. High echocardiographic LV relative wall thickness in hypertensive LV hypertrophy allows preserved endocardial excursion despite depressed LV midwall shortening (MWS). Depressed MWS is an adverse prognostic indicator, but whether this is related to global or regional myocardial depression is unknown. We prospectively compared MWS derived from linear echocardiographic dimensions with MR strain(in) in septal and posterior locations in 27 subjects with ECG LV hypertrophy in the Losartan Intervention for Endpoint Reduction in Hypertension Study. Although MRI-derived mass was higher in patients than in normal control subjects (124.0+/-38.6 versus 60.5+/-13.2g/m(2); P<0.001), fractional shortening (30+/-5% versus 33+/-3%) and end-systolic stress (175+/-22 versus 146+/-28 g/cm(2)) did not differ between groups. However, mean MR(in) was decreased in patients versus normal control subjects (13.9+/-6.8% versus 22.4+/-3.5%), as was echo MWS (13.4+/-2.8% versus 18.2+/-1.4%; both P<0.001). For patients versus normal control subjects, posterior wall(in) was not different (17.8+/-7.1% versus 21.6+/-4.0%), whereas septal(in) was markedly depressed (10.1+/-6.6% versus 23.2+/-3.4%; P<0.001). Although global MWS by echocardiography or MRI is depressed in hypertensive LV hypertrophy, MRI tissue tagging demonstrates substantial regional intramyocardial strain(in) heterogeneity, with most severely depressed strain patterns in the septum. Although posterior wall 2D principal strain was inversely related to radius of curvature, septal strain was not, suggesting that factors other than afterload are responsible for pronounced myocardial strain heterogeneity in concentric hypertrophy.
The impact of age and frailty on ventricular structure and function in C57BL/6J mice
Feridooni, H. A.; Kane, A. E.; Ayaz, O.; Boroumandi, A.; Polidovitch, N.; Tsushima, R. G.; Rose, R. A.
2017-01-01
Key points Heart size increases with age (called hypertrophy), and its ability to contract declines. However, these reflect average changes that may not be present, or present to the same extent, in all older individuals.That aging happens at different rates is well accepted clinically. People who are aging rapidly are frail and frailty is measured with a ‘frailty index’.We quantified frailty with a validated mouse frailty index tool and evaluated the impacts of age and frailty on cardiac hypertrophy and contractile dysfunction.Hypertrophy increased with age, while contractions, calcium currents and calcium transients declined; these changes were graded by frailty scores.Overall health status, quantified as frailty, may promote maladaptive changes associated with cardiac aging and facilitate the development of diseases such as heart failure.To understand age‐related changes in heart structure and function, it is essential to know both chronological age and the health status of the animal. Abstract On average, cardiac hypertrophy and contractile dysfunction increase with age. Still, individuals age at different rates and their health status varies from fit to frail. We investigated the influence of frailty on age‐dependent ventricular remodelling. Frailty was quantified as deficit accumulation in adult (≈7 months) and aged (≈27 months) C57BL/6J mice by adapting a validated frailty index (FI) tool. Hypertrophy and contractile function were evaluated in Langendorff‐perfused hearts; cellular correlates/mechanisms were investigated in ventricular myocytes. FI scores increased with age. Mean cardiac hypertrophy increased with age, but values in the adult and aged groups overlapped. When plotted as a function of frailty, hypertrophy was graded by FI score (r = 0.67–0.55, P < 0.0003). Myocyte area also correlated positively with FI (r = 0.34, P = 0.03). Left ventricular developed pressure (LVDP) plus rates of pressure development (+dP/dt) and decay (−dP/dt) declined with age and this was graded by frailty (r = −0.51, P = 0.0007; r = −0.48, P = 0.002; r = −0.56, P = 0.0002 for LVDP, +dP/dt and −dP/dt). Smaller, slower contractions graded by FI score were also seen in ventricular myocytes. Contractile dysfunction in cardiomyocytes isolated from frail mice was attributable to parallel changes in underlying Ca2+ transients. These changes were not due to reduced sarcoplasmic reticulum stores, but were graded by smaller Ca2+ currents (r = −0.40, P = 0.008), lower gain (r = −0.37, P = 0.02) and reduced expression of Cav1.2 protein (r = −0.68, P = 0.003). These results show that cardiac hypertrophy and contractile dysfunction in naturally aging mice are graded by overall health and suggest that frailty, in addition to chronological age, can help explain heterogeneity in cardiac aging. PMID:28502095
Changes in Myocardial Mass Associated with Age and Stress: Reexamination of Ventricular Hypertrophy.
ERIC Educational Resources Information Center
George, Colleen; And Others
1985-01-01
One hundred twenty-six rats were studied to determine the effects of exercise, high altitude, and age upon right and left ventricular mass. Chronically hypoxic rats had significantly larger right ventricles but significantly smaller left ventricles than exercised or control rats. (Author/MT)
Molina, Ezequiel J; Palma, Jon; Gupta, Dipin; Torres, Denise; Gaughan, John P; Houser, Steven; Macha, Mahender
2009-02-01
Changes in ventricular extracellular matrix (ECM) composition of pressure overload hypertrophy determine clinical outcomes. The effects of mesenchymal stem cell (MSC) transplantation upon determinants of ECM composition in pressure overload hypertrophy have not been studied. Sprague-Dawley rats underwent aortic banding and were followed by echocardiography. After an absolute decrease in fractional shortening of 25% from baseline, 1 x 10(6) MSC (n = 28) or PBS (n = 20) was randomly injected intracoronarily. LV protein analysis, including matrix metalloproteinases (MMP-2, MMP-3, MMP-6, MMP-9) and tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2, TIMP-3), was performed after sacrifice on postoperative day 7, 14, 21 or 28. Left ventricular levels of MMP-3, MMP-6, MMP-9, TIMP-1 and TIMP-3 were demonstrated to be decreased in the MSC group compared with controls after 28 days. Expression of MMP-2 and TIMP-2 remained relatively stable in both groups. Successful MSCs delivery was confirmed by histological analysis and visualization of labelled MSCs. In this model of pressure overload hypertrophy, intracoronary delivery of MSCs during heart failure was associated with specific changes in determinants of ECM composition. LV reverse remodeling was associated with decreased ventricular levels of MMP-3, MMP-6, MMP-9, TIMP-1 and TIMP-3, which were upregulated in the control group as heart failure progressed. These effects were most significant at 28 days following injection. (c) 2008 John Wiley & Sons, Ltd.
Miller, Clint L.; Oikawa, Masayoshi; Cai, Yujun; Wojtovich, Andrew P.; Nagel, David J.; Xu, Xiangbin; Xu, Haodong; Florio, Vince; Rybalkin, Sergei D.; Beavo, Joseph A.; Chen, Yiu-Fai; Li, Jian-Dong; Blaxall, Burns C.; Abe, Jun-ichi; Yan, Chen
2009-01-01
Rationale Cyclic nucleotide phosphodiesterases (PDE) through the degradation of second messenger cyclic guanosine monophosphate (cGMP) play critical roles in maintaining cardiomyocyte homeostasis. Ca2+/CaM-activated cGMP-hydrolyzing PDE1 family may play a pivotal role in balancing intracellular Ca2+/CaM and cGMP signaling, however its function in cardiomyocytes is unknown. Objective Herein we investigate the role of Ca2+/CaM-stimulated PDE1 in regulating pathological cardiomyocyte hypertrophy in neonatal and adult rat ventricular myocytes (NRVM and ARVM) and in the heart in vivo. Methods and Results Inhibition of PDE1 activity using a PDE1 selective inhibitor IC86340 or downregulation of PDE1A using siRNA prevented phenylephrine (PE) induced pathological myocyte hypertrophy and hypertrophic marker expression in neonatal (NRVM) and adult (ARVM) rat ventricular myocytes. Importantly, administration of the PDE1 inhibitor IC86340 attenuated cardiac hypertrophy induced by chronic ISO infusion in vivo. Both PDE1A and PDE1C mRNA and protein were detected in human hearts, however PDE1A expression was conserved in rodent hearts. Moreover, PDE1A expression was significantly upregulated in vivo in the heart and myocytes from various pathological hypertrophy animal models and in vitro in isolated NRVM and ARVM treated with neurohumoral stimuli such as angiotensin II (Ang II) and ISO. Further, PDE1A plays a critical role in PE-induced reduction of intracellular cGMP and PKG activity, and thereby cardiomyocyte hypertrophy in vitro. Conclusions These results elucidate a novel role for Ca2+/CaM-stimulated PDE1, particularly PDE1A, in regulating pathological cardiomyocyte hypertrophy via a cGMP/PKG-dependent mechanism, thereby demonstrating Ca2+ and cGMP signaling cross-talk during cardiac hypertrophy. PMID:19797176
Yang, Kai-Chien; Tseng, Yi-Tang; Nerbonne, Jeanne M.
2012-01-01
In contrast with pathological hypertrophy, exercise-induced physiological hypertrophy is not associated with electrical abnormalities or increased arrhythmia risk. Recent studies have shown that increased cardiac-specific expression of phosphoinositide-3-kinase-α (PI3Kα), the key mediator of physiological hypertrophy, results in transcriptional upregulation of ion channel subunits in parallel with the increase in myocyte size (cellular hypertrophy) and the maintenance of myocardial excitability. The experiments here were undertaken to test the hypothesis that Akt1, which underlies PI3Kα-induced cellular hypertrophy, mediates the effects of augmented PI3Kα signaling on the transcriptional regulation of cardiac ion channels. In contrast to wild-type animals, chronic exercise (swim) training of mice (Akt1−/−) lacking Akt1 did not result in ventricular myocyte hypertrophy. Ventricular K+ current amplitudes and the expression of K+ channel subunits, however, were increased markedly in Akt1−/− animals with exercise training. Expression of the transcripts encoding inward (Na+ and Ca2+) channel subunits were also increased in Akt1−/− ventricles following swim training. Additional experiments in a transgenic mouse model of inducible cardiac-specific expression of constitutively active PI3Kα (icaPI3Kα) revealed that short-term activation of PI3Kα signaling in the myocardium also led to the transcriptional upregulation of ion channel subunits. Inhibition of cardiac Akt activation with triciribine in this (inducible caPI3Kα expression) model did not prevent the upregulation of myocardial ion channel subunits. These combined observations demonstrate that chronic exercise training and enhanced PI3Kα expression/activity result in transcriptional upregulation of myocardial ion channel subunits independent of cellular hypertrophy and Akt signaling. PMID:22824041
Absence of left ventricular concentric hypertrophy: a prerequisite for zero coronary calcium score.
Ehara, Shoichi; Shirai, Nobuyuki; Okuyama, Takuhiro; Matsumoto, Kenji; Matsumura, Yoshiki; Yoshiyama, Minoru
2011-09-01
The identification and intervention of factors associated with a coronary artery calcification (CAC) score of zero, suggesting the absence of significant coronary artery disease (CAD) with high probability, would be meaningful in the clinical setting. Thus far, the relationship between CAC and left ventricular (LV) hypertrophy has not been documented. We identified factors associated with a CAC score of zero and evaluated the relationship between this score and LV concentric hypertrophy in 309 consecutive patients with suspected CAD who were clinically indicated to undergo multislice computed tomography angiography for coronary artery evaluation. The quantitative CAC score was calculated according to Agatston's method. The total coronary calcium score (TCS) was defined as the sum of the scores for each lesion. Four absolute TCS categories were considered: zero, mild (0-100), moderate (100-400), and severe (>400). LV hypertrophy was classified into concentric (LV mass index >104 g/m(2) in women or >116 g/m(2) in men; LV end-diastolic volume index ≤109.2 mL/m(2)) and eccentric (LV end-diastolic volume index >109.2 mL/m(2)) patterns. In the zero-TCS group, the frequency of LV concentric hypertrophy was extremely low (zero 6%, mild 17%, moderate 26%, severe 19%). Multivariate analysis revealed that age, hypercholesterolemia, diabetes mellitus, LV concentric hypertrophy, and LV mass index, but not hypertension, were the independent factors associated with a CAC score of zero. The present study demonstrated that the absence of LV concentric hypertrophy was a prerequisite for a CAC score of zero. That is, the presence of LV concentric hypertrophy, which indicated more severe underlying hypertension, long duration, or poor control of blood pressure, implicates the presence of CAC.
Lim, Soyeon; Lee, Myung Eun; Jeong, Jisu; Lee, Jiye; Cho, Soyoung; Seo, Miran; Park, Sungha
2018-05-23
The receptor for advanced glycation endproducts (RAGE) is an innate immunity receptor that has been implicated in the pathogenesis of atherosclerotic cardiovascular disease. However, the possibility that RAGE-mediated signaling is involved in angiotensin II (Ang II)-induced cardiac left ventricular hypertrophy has yet to be investigated. We therefore determined whether RAGE has a role in regulating pathological cardiac hypertrophy. Protein abundance was estimated using Western blotting and intracellular ROS level and phospho-p65 were detected using fluorescence microscopy. Enzyme-linked immunosorbent assay was used to detect HMGB1 and IL-1β. All in vitro experiments were performed using H9C2 cells. To induce cardiomyocyte hypertrophy, 300 nM Ang II was treated for 48 h and 2 µg/ml sRAGE was treated 1 h prior to addition of Ang II. sRAGE attenuated Ang II-induced cardiomyocyte hypertrophy by downregulating RAGE and angiotensin II type 1 receptor expression. Secretion levels of high motility group box 1 and interleukin-1β, estimated from a cell culture medium, were significantly reduced by sRAGE. Activated PKCs and ERK1/2, important signals in left ventricular hypertrophy (LVH) development, were downregulated by sRAGE treatment. Furthermore, we found that nuclear factor-κB and NOD-like receptor protein 3 (NLRP3) were associated with RAGE-mediated cardiomyocyte hypertrophy. In the context of these results, we conclude that RAGE induces cardiac hypertrophy through the activation of the PKCs-ERK1/2 and NF-κB-NLRP3-IL1β signaling pathway, and suggest that RAGE-NLRP3 may be an important mediator of Ang II-induced cardiomyocyte hypertrophy. In addition, we determined that inhibition of RAGE activation with soluble RAGE (sRAGE) has a protective effect on Ang II-induced cardiomyocyte hypertrophy.
Mechanisms of physiological and pathological cardiac hypertrophy.
Nakamura, Michinari; Sadoshima, Junichi
2018-04-19
Cardiomyocytes exit the cell cycle and become terminally differentiated soon after birth. Therefore, in the adult heart, instead of an increase in cardiomyocyte number, individual cardiomyocytes increase in size, and the heart develops hypertrophy to reduce ventricular wall stress and maintain function and efficiency in response to an increased workload. There are two types of hypertrophy: physiological and pathological. Hypertrophy initially develops as an adaptive response to physiological and pathological stimuli, but pathological hypertrophy generally progresses to heart failure. Each form of hypertrophy is regulated by distinct cellular signalling pathways. In the past decade, a growing number of studies have suggested that previously unrecognized mechanisms, including cellular metabolism, proliferation, non-coding RNAs, immune responses, translational regulation, and epigenetic modifications, positively or negatively regulate cardiac hypertrophy. In this Review, we summarize the underlying molecular mechanisms of physiological and pathological hypertrophy, with a particular emphasis on the role of metabolic remodelling in both forms of cardiac hypertrophy, and we discuss how the current knowledge on cardiac hypertrophy can be applied to develop novel therapeutic strategies to prevent or reverse pathological hypertrophy.
Afonso, Luis; Kondur, Ashok; Simegn, Mengistu; Niraj, Ashutosh; Hari, Pawan; Kaur, Ramanjit; Ramappa, Preeti; Pradhan, Jyotiranjan; Bhandare, Deepti; Williams, Kim A; Zalawadiya, Sandip; Pinheiro, Aurelio; Abraham, Theodore P
2012-01-01
This study was designed to examine the utility of two-dimensional strain (2DS) or speckle tracking imaging to typify functional adaptations of the left ventricle in variant forms of left ventricular hypertrophy (LVH). Cross-sectional study. Urban tertiary care academic medical centres. A total of 129 subjects, 56 with hypertrophic cardiomyopathy (HCM), 34 with hypertensive left ventricular hypertrophy (H-LVH), 27 professional athletes with LVH (AT-LVH) and 12 healthy controls in sinus rhythm with preserved left ventricular systolic function. Conventional echocardiographic and tissue Doppler examinations were performed in all study subjects. Bi-dimensional acquisitions were analysed to map longitudinal systolic strain (automated function imaging, AFI, GE Healthcare, Waukesha, Wisconsin, USA) from apical views. Subjects with HCM had significantly lower regional and average global peak longitudinal systolic strain (GLS-avg) compared with controls and other forms of LVH. Strain dispersion index, a measure of regional contractile heterogeneity, was higher in HCM compared with the rest of the groups. On receiver operator characteristics analysis, GLS-avg had excellent discriminatory ability to distinguish HCM from H-LVH area under curve (AUC) (0.893, p<0.001) or AT-LVH AUC (0.920, p<0.001). Tissue Doppler and LV morphological parameters were better suited to differentiate the athlete heart from HCM. 2DS (AFI) allows rapid characterisation of regional and global systolic function and may have the potential to differentiate HCM from variant forms of LVH.
Sarr, Simon Antoine; Babaka, Kana; Mboup, Mouhamadou Cherif; Fall, Pape Diadie; Dia, Khadidiatou; Bodian, Malick; Ndiaye, Mouhamadou Bamba; Kane, Adama; Diao, Maboury; Ba, Serigne Abdou
2016-01-01
Arterial hypertension (HTA) in the elderly is an independent risk factor for cardiovascular disease. Our study aims to describe the clinical, electrocardiographic and echocardiographic aspects of Arterial hypertension in elderly patients. We conducted a descriptive, cross-sectional study from January to September 2013. Hypertensive patients =60 years treated in Outpatient Cardiology Department at the Principal Hospital in Dakar were included in the study. Statistical data were analyzed using Epi Info 7 software and a p-value < 0.05 was taken as significant. A total of 208 patients were enrolled in the study. The average age was 69.9 years with a female predominance (sex ratio 0.85). Average blood pressure was 162/90 mm Hg. HTA was under control in 13% of cases. The ECG showed evidence of rhythm disturbance (17.78%), left atrial enlargement (45.19%), left ventricular hypertrophy (28.85%) and complete atrioventricular block in 2 cases. Holter ECG revealed non-sustained ventricular tachycardia (Lown class IVb) in 4 cases, paroxysmal atrial fibrillation in 6 cases and paroxysmal atrial flutter in 1 case. Echocardiography performed in 140 patients showed mainly concentric left ventricular hypertrophy in 25 patients, occuring more frequently in males (p=0,04) and dilated left atrium in 56,42% of cases, occuring more frequently in elderly patients (p= 0,01). Electrocardiographic and echocardiographic aspects in elderly hypertensive population are characterized by concentric left ventricular hypertrophy and by the frequency of arrhythmias sometimes revealed by long-term continuous external electrocardiographic recording.
Singla, Varun; Jindal, Akash; Pargaonkar, Vedant; Soofi, Muhammad; Wheeler, Matthew; Froelicher, Victor
2015-01-01
Current guidelines for interpretation of the ECGs of athletes recommend that isolated R and S wave amplitudes that exceed traditional criteria for left ventricular hypertrophy be accepted as a physiological response to exercise training. This is based on training and echocardiographic studies but not on long term follow up. Demonstration of the prognostic characteristics of the amplitude criteria in a non-athletic population could support the current guidelines. To evaluate the prognostic value of the R and S wave voltage criteria for electrocardiographic left ventricular hypertrophy (ECG-LVH) in an ambulatory clinical population. The target population consisted of 20,903 ambulatory subjects who had ECGs recorded between 1987 and 1999 and were followed for cardiovascular death until 2013. During the mean follow up of 17 years, there were 881 cardiovascular deaths. The mean age was 43 ± 10, 91% were male and 16% were African American. Of the 2482 (12%) subjects who met the Sokolow-Lyon criteria, 241 (1.2%) subjects with left ventricular (LV) strain had an HR of 5.4 (95% CI 4.1-7.2, p<0.001), while 2241 (11%) subjects without strain had an HR of 1.4 (95% CI 1.2-1.8, p<0.001). Of the 4836 (23%) subjects who met the Framingham voltage criteria, 350 (2%) subjects with LV strain had an HR of 5.1 (95% CI 4.0-6.5, p<0.001), while 4486 (22%) subjects without strain had an HR of 1.1 (95% CI 0.9-1.3, p=0.26). The individual components of the Romhilt-Estes had HRs ranging from 1.4 to 3.6, with only the voltage component not being significant (HR 1.1, 95% CI 0.9-1.5, p=0.35). This study demonstrates that the R and S wave voltage criteria components of most of the original classification schema for electrocardiographic left ventricular hypertrophy are not predictive of CV mortality. Our findings support the current guidelines for electrocardiographic screening of athletes. Copyright © 2015 Elsevier Inc. All rights reserved.
Left ventricular hypertrophy with strain and aortic stenosis.
Shah, Anoop S V; Chin, Calvin W L; Vassiliou, Vassilis; Cowell, S Joanna; Doris, Mhairi; Kwok, T'ng Choong; Semple, Scott; Zamvar, Vipin; White, Audrey C; McKillop, Graham; Boon, Nicholas A; Prasad, Sanjay K; Mills, Nicholas L; Newby, David E; Dweck, Marc R
2014-10-28
ECG left ventricular hypertrophy with strain is associated with an adverse prognosis in aortic stenosis. We investigated the mechanisms and outcomes associated with ECG strain. One hundred and two patients (age, 70 years [range, 63-75 years]; male, 66%; aortic valve area, 0.9 cm(2) [range, 0.7-1.2 cm(2)]) underwent ECG, echocardiography, and cardiovascular magnetic resonance. They made up the mechanism cohort. Myocardial fibrosis was determined with late gadolinium enhancement (replacement fibrosis) and T1 mapping (diffuse fibrosis). The relationship between ECG strain and cardiovascular magnetic resonance was then assessed in an external validation cohort (n=64). The outcome cohort was made up of 140 patients from the Scottish Aortic Stenosis and Lipid Lowering Trial Impact on Regression (SALTIRE) study and was followed up for 10.6 years (1254 patient-years). Compared with those without left ventricular hypertrophy (n=51) and left ventricular hypertrophy without ECG strain (n=30), patients with ECG strain (n=21) had more severe aortic stenosis, increased left ventricular mass index, more myocardial injury (high-sensitivity plasma cardiac troponin I concentration, 4.3 ng/L [interquartile range, 2.5-7.3 ng/L] versus 7.3 ng/L [interquartile range, 3.2-20.8 ng/L] versus 18.6 ng/L [interquartile range, 9.0-45.2 ng/L], respectively; P<0.001) and increased diffuse fibrosis (extracellular volume fraction, 27.4±2.2% versus 27.2±2.9% versus 30.9±1.9%, respectively; P<0.001). All patients with ECG strain had midwall late gadolinium enhancement (positive and negative predictive values of 100% and 86%, respectively). Indeed, late gadolinium enhancement was independently associated with ECG strain (odds ratio, 1.73; 95% confidence interval, 1.08-2.77; P=0.02), a finding confirmed in the validation cohort. In the outcome cohort, ECG strain was an independent predictor of aortic valve replacement or cardiovascular death (hazard ratio, 2.67; 95% confidence interval, 1.35-5.27; P<0.01). ECG strain is a specific marker of midwall myocardial fibrosis and predicts adverse clinical outcomes in aortic stenosis. © 2014 American Heart Association, Inc.
Somauroo, J; Pyatt, J; Jackson, M; Perry, R; Ramsdale, D
2001-01-01
OBJECTIVE—To assess physiological cardiac adaptation in adolescent professional soccer players. SUBJECTS AND DESIGN—Over a 32 month period 172 teenage soccer players were screened by echocardiography and ECG at a tertiary referral cardiothoracic centre. They were from six professional soccer teams in the north west of England, competing in the English Football League. One was excluded because of an atrial septal defect. The median age of the 171 players assessed was 16.7 years (5th to 95th centile range: 14-19) and median body surface area 1.68 m2 (1.39-2.06 m2). MAIN OUTCOME MEASURES—Standard echocardiographic measurements were compared with predicted mean, lower, and upper limits in a cohort of normal controls after matching for age and surface area. Univariate regression analysis was used to assess the correlation between echocardiographic variables and the age and surface area of the soccer player cohort. ECG findings were also assessed. RESULTS—All mean echocardiographic variables were greater than predicted for age and surface area matched controls (p < 0.001). All variables except left ventricular septal and posterior wall thickness showed a modest linear correlation with surface area (r = 0.2 to 0.4, p < 0.001); however, left ventricular mass was the only variable that was significantly correlated with age (r = 0.2, p < 0.01). Only six players (3.5%) had structural anomalies, none of which required further evaluation. All had normal left ventricular systolic function. Sinus bradycardia was found in 65 (39%). The Solokow-Lyon voltage criteria for left ventricular hypertrophy were present in 85 (50%) and the Romhilt-Estes points score (five or more) in 29 (17%). Repolarisation changes were present in 19 (11%), mainly in the inferior leads. CONCLUSIONS—Chamber dimensions, left ventricular wall thickness and mass, and aortic root size were all greater than predicted for controls after matching for age and surface area. Sinus bradycardia and the ECG criteria for left ventricular hypertrophy were common but there was poor correlation with echocardiographic left ventricular hypertrophy. The type of hypertrophy found reflected the combined endurance and strength based training undertaken. Keywords: cardiac morphology; professional soccer players; echocardiography; ECG findings PMID:11359746
Sulovic, Ljiljana S; Mahmutovic, Meho; Lazic, Snezana; Sulovic, Nenad
2017-05-01
Aims "Athlete's heart" is a cardiac adaptation to long-term intensive training. The aims of this study were to show the prevalence of left ventricular hypertrophy in teenagers who participate in sports, to define the different types of cardiac re-modelling, and to differentiate between physiological and pathological hypertrophy. Echocardiographic measurements were obtained by M-mode, two dimensional, and Doppler techniques of participants from sports and control groups. The echocardiographic examinations included 100 healthy teenagers taking part in dynamic sports such as football and basketball and 100 healthy teenagers taking part in static sports such as karate and judo. The control group (n=100) included healthy, sedentary teenagers. Sports participants had significantly higher left ventricular mass when compared with the control group, (p0.05). Respondents from both groups had E/A ratios (transmitral flow velocity ratio)>1, preserved diastolic function, and statistically they did not differ from the control group. Echocardiographic parameters show that physiological hypertrophy and cardiac re-modelling are present in teenagers who play sports. Unexpectedly, the prevalence of concentric and eccentric types of re-modelling is equally possible in the group of static sports participants.
The role of autophagy in cardiac hypertrophy
Li, Lanfang; Xu, Jin; He, Lu; Peng, Lijun; Zhong, Qiaoqing; Chen, Linxi; Jiang, Zhisheng
2016-01-01
Autophagy is conserved in nature from lower eukaryotes to mammals and is an important self-cannibalizing, degradative process that contributes to the elimination of superfluous materials. Cardiac hypertrophy is primarily characterized by excess protein synthesis, increased cardiomyocyte size, and thickened ventricular walls and is a major risk factor that promotes arrhythmia and heart failure. In recent years, cardiomyocyte autophagy has been considered to play a role in controlling the hypertrophic response. However, the beneficial or aggravating role of cardiomyocyte autophagy in cardiac hypertrophy remains controversial. The exact mechanism of cardiomyocyte autophagy in cardiac hypertrophy requires further study. In this review, we summarize the controversies associated with autophagy in cardiac hypertrophy and provide insights into the role of autophagy in the development of cardiac hypertrophy. We conclude that future studies should emphasize the relationship between autophagy and the different stages of cardiac hypertrophy, as well as the autophagic flux and selective autophagy. Autophagy will be a potential therapeutic target for cardiac hypertrophy. PMID:27084518
Helder, Meghana R K; Ugur, Murat; Bavaria, Joseph E; Kshettry, Vibhu R; Groh, Mark A; Petracek, Michael R; Jones, Kent W; Suri, Rakesh M; Schaff, Hartzell V
2015-03-01
The study objective was to analyze factors associated with left ventricular mass regression in patients undergoing aortic valve replacement with a newer bioprosthesis, the Trifecta valve pericardial bioprosthesis (St Jude Medical Inc, St Paul, Minn). A total of 444 patients underwent aortic valve replacement with the Trifecta bioprosthesis from 2007 to 2009 at 6 US institutions. The clinical and echocardiographic data of 200 of these patients who had left ventricular hypertrophy and follow-up studies 1 year postoperatively were reviewed and compared to analyze factors affecting left ventricular mass regression. Mean (standard deviation) age of the 200 study patients was 73 (9) years, 66% were men, and 92% had pure or predominant aortic valve stenosis. Complete left ventricular mass regression was observed in 102 patients (51%) by 1 year postoperatively. In univariate analysis, male sex, implantation of larger valves, larger left ventricular end-diastolic volume, and beta-blocker or calcium-channel blocker treatment at dismissal were significantly associated with complete mass regression. In the multivariate model, odds ratios (95% confidence intervals) indicated that male sex (3.38 [1.39-8.26]) and beta-blocker or calcium-channel blocker treatment at dismissal (3.41 [1.40-8.34]) were associated with increased probability of complete left ventricular mass regression. Patients with higher preoperative systolic blood pressure were less likely to have complete left ventricular mass regression (0.98 [0.97-0.99]). Among patients with left ventricular hypertrophy, postoperative treatment with beta-blockers or calcium-channel blockers may enhance mass regression. This highlights the need for close medical follow-up after operation. Labeled valve size was not predictive of left ventricular mass regression. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
[Study on the correlation between adenoid hypertrophy and laryngopharyngeal reflux in children].
Huang, Y D; Tan, J J; Han, X Y; Zeng, F F; Li, Y F; Wang, L; Li, X P
2018-06-01
Objective: To discuss the correlation between adenoid hypertrophy and laryngopharyngeal reflux in children, and to determine the accuracy of reflux symptom index(RSI) and reflux finding score(RFS) in predicting adenoid hypertrophy and laryngopharyngeal reflux(LPR). Method: Assessment of RSI and RFS was performed in 71 children with adenoid hypertrophy who underwent surgery.The adenoid biopsy specimens were examined by pepsin immunohistochemical staining. According to the positive results of pepsin staining to evaluate the sensitivity and specificity of RSI and RFS to predict LPR. Result: Among the 71 children with adenoid hypertrophy, RSI was greater than 13 points in 4 cases (5.63%), RFS was greater than 7 points in 26 cases (36.62%), and 1(1.41%) was positive in both scores. Pepsin expression was detected in 52 cases of adenoid hypertrophy tissues, with a total positive rate of 73.24% (52/71),most were strong positive(15/71,21.13%)and positive(23/71,32.39%). The higher the adenoid hypertrophy grade, the higher the expression level of pepsin ( r =0.476, P <0.01).Define the positive rate of pepsin as the gold standard for the diagnosis of LPR, the sensitivity and specificity of RSI and RFS were 5.77%,34.62% and 94.74%,57.89% respectively. Pepsin staining intensity was positively correlated with troublesome or annoying cough( r =0.356, P =0.002)and was negatively correlated with ventricular obliteration( r =-0.212, P =0.038). Conclusion: There is a correlation between adenoid hypertrophy and LPR in children,LPR plays an important role in the development of adenoid and the role and mechanism of pepsin in adenoid hypertrophy needs further studyAs the low sensitivity of RSI and RFS, it is not suitable for the screening of adenoid hypertrophy in children with LPR. Children with adenoid hypertrophy cough for a long time and the laryngoscopy shows the ventricular obliteration, the presence of LPR should be warned. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.
Stratton, Matthew S.; McKinsey, Timothy A.
2016-01-01
Acetylation of lysine residues within nucleosomal histone tails provides a crucial mechanism for epigenetic control of gene expression. Acetyl groups are coupled to lysine residues by histone acetyltransferases (HATs) and removed by histone deacetylases (HDACs), which are also commonly referred to as “writers” and “erasers”, respectively. In addition to altering the electrostatic properties of histones, lysine acetylation often creates docking sites for bromodomain-containing “reader” proteins. This review focuses on epigenetic control of pulmonary hypertension (PH) and associated right ventricular (RV) cardiac hypertrophy and failure. Effects of small molecule HDAC inhibitors in pre-clinical models of PH are highlighted. Furthermore, we describe the recently discovered role of bromodomain and extraterminal (BET) reader proteins in the control of cardiac hypertrophy, and provide evidence suggesting that one member of this family, BRD4, contributes to the pathogenesis of RV failure. Together, the data suggest intriguing potential for pharmacological epigenetic therapies for the treatment of PH and right-sided heart failure. PMID:25707943
Morphometry of right ventricular hypertrophy induced by myocardial infarction in the rat.
Anversa, P.; Beghi, C.; McDonald, S. L.; Levicky, V.; Kikkawa, Y.; Olivetti, G.
1984-01-01
The growth response of the right ventricle was studied in rats following ligation of the left coronary artery, which produced infarcts comprising approximately 40% of the left ventricle. A month after surgery the weight of the right ventricle was increased 30%, and this hypertrophic change was characterized by a 17% wall thickening, consistent with the 13% greater diameter of myocytes. Myocardial hypertrophy was accompanied by an inadequate growth of the microvasculature that supports tissue oxygenation. This was seen by relative decreases in capillary luminal volume density (-27%) and capillary luminal surface density (-21%) and by an increase in the average maximum distance from the capillary wall to the mitochondria of myocytes (19%). In contrast, measurements of the mean myocyte volume per nucleus showed a proportional enlargement of these cells (32%), from 16,300 cu mu in control animals to 21,500 cu mu in experimental rats. Quantitative analysis of the right coronary artery revealed a 33% increase in its luminal area, commensurate with the magnitude of ventricular hypertrophy. PMID:6236695
Dassanayaka, Sujith; Brainard, Robert E; Watson, Lewis J; Long, Bethany W; Brittian, Kenneth R; DeMartino, Angelica M; Aird, Allison L; Gumpert, Anna M; Audam, Timothy N; Kilfoil, Peter J; Muthusamy, Senthilkumar; Hamid, Tariq; Prabhu, Sumanth D; Jones, Steven P
2017-05-01
The myocardial response to pressure overload involves coordination of multiple transcriptional, posttranscriptional, and metabolic cues. The previous studies show that one such metabolic cue, O-GlcNAc, is elevated in the pressure-overloaded heart, and the increase in O-GlcNAcylation is required for cardiomyocyte hypertrophy in vitro. Yet, it is not clear whether and how O-GlcNAcylation participates in the hypertrophic response in vivo. Here, we addressed this question using patient samples and a preclinical model of heart failure. Protein O-GlcNAcylation levels were increased in myocardial tissue from heart failure patients compared with normal patients. To test the role of OGT in the heart, we subjected cardiomyocyte-specific, inducibly deficient Ogt (i-cmOgt -/- ) mice and Ogt competent littermate wild-type (WT) mice to transverse aortic constriction. Deletion of cardiomyocyte Ogt significantly decreased O-GlcNAcylation and exacerbated ventricular dysfunction, without producing widespread changes in metabolic transcripts. Although some changes in hypertrophic and fibrotic signaling were noted, there were no histological differences in hypertrophy or fibrosis. We next determined whether significant differences were present in i-cmOgt -/- cardiomyocytes from surgically naïve mice. Interestingly, markers of cardiomyocyte dedifferentiation were elevated in Ogt-deficient cardiomyocytes. Although no significant differences in cardiac dysfunction were apparent after recombination, it is possible that such changes in dedifferentiation markers could reflect a larger phenotypic shift within the Ogt-deficient cardiomyocytes. We conclude that cardiomyocyte Ogt is not required for cardiomyocyte hypertrophy in vivo; however, loss of Ogt may exert subtle phenotypic differences in cardiomyocytes that sensitize the heart to pressure overload-induced ventricular dysfunction.
Seko, Yuta; Kato, Takao; Haruna, Tetsuya; Izumi, Toshiaki; Miyamoto, Shoichi; Nakane, Eisaku; Inoko, Moriaki
2018-04-23
This study investigated the relationship between atrial fibrillation (AF) and left ventricular (LV) geometric patterns in a hospital-based population in Japan. We retrospectively analyzed 4444 patients who had undergone simultaneous scheduled transthoracic echocardiography (TTE) and electrocardiography during 2013. A total of 430 patients who had findings of previous myocardial infarctions (n = 419) and without the data on body surface area (n = 11) were excluded from the study. We calculated the LV mass index (LVMI) and relative wall (RWT) and categorized 4014 patients into four groups as follows: normal geometry (n = 3046); concentric remodeling (normal LVMI and high RWT, n = 437); concentric hypertrophy (high LVMI and high RWT, n = 149); and eccentric remodeling (high LVMI and normal RWT, n = 382). The mean left atrial volume indices (LAVI) were 22.5, 23.8, 33.3, and 37.0 mm/m 2 in patients with normal geometry, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy, respectively. The mean LV ejection fractions (LVEF) were 62.7, 62.6, 60.8, and 53.8%, respectively, whereas the prevalence of AF was 10.4%, 10.5%, 14.8%, and 16.8% in patients with normal geometry, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy, respectively. In conclusion, the prevalence of AF was increasing according to LV geometric remodeling patterns in association with LA size and LVEF.
Kerckhoffs, Roy C.P.; Omens, Jeffrey; McCulloch, Andrew D.
2011-01-01
Adult cardiac muscle adapts to mechanical changes in the environment by growth and remodeling (G&R) via a variety of mechanisms. Hypertrophy develops when the heart is subjected to chronic mechanical overload. In ventricular pressure overload (e.g. due to aortic stenosis) the heart typically reacts by concentric hypertrophic growth, characterized by wall thickening due to myocyte radial growth when sarcomeres are added in parallel. In ventricular volume overload, an increase in filling pressure (e.g. due to mitral regurgitation) leads to eccentric hypertrophy as myocytes grow axially by adding sarcomeres in series leading to ventricular cavity enlargement that is typically accompanied by some wall thickening. The specific biomechanical stimuli that stimulate different modes of ventricular hypertrophy are still poorly understood. In a recent study, based on in-vitro studies in micropatterned myocyte cell cultures subjected to stretch, we proposed that cardiac myocytes grow longer to maintain a preferred sarcomere length in response to increased fiber strain and grow thicker to maintain interfilament lattice spacing in response to increased cross-fiber strain. Here, we test whether this growth law is able to predict concentric and eccentric hypertrophy in response to aortic stenosis and mitral valve regurgitation, respectively, in a computational model of the adult canine heart coupled to a closed loop model of circulatory hemodynamics. A non-linear finite element model of the beating canine ventricles coupled to the circulation was used. After inducing valve alterations, the ventricles were allowed to adapt in shape in response to mechanical stimuli over time. The proposed growth law was able to reproduce major acute and chronic physiological responses (structural and functional) when integrated with comprehensive models of the pressure-overloaded and volume-overloaded canine heart, coupled to a closed-loop circulation. We conclude that strain-based biomechanical stimuli can drive cardiac growth, including wall thickening during pressure overload. PMID:22639476
Liu, Li; Wang, Wen; Meng, Xianmin; Gao, Jiuming; Wu, Haiying; Wang, Peihe; Wu, Weichun; Wang, Linlin; Ma, Liyuan; Zhang, Weiguo
2010-12-01
Cardiac hypertrophy is frequently caused by pressure overload (i.e., high blood pressure or hypertension) and can lead to heart failure. The major objective of the present study was to investigate the proteomic changes in response to the development of left ventricular hypertrophy (LVH) induced by abdominal aortic banding (AB) and its prevention by antihypertensive treatment with angiotensin II receptor blocker (ARB) telmisartan. One week after AB and Sham surgery, rats were assigned into three groups: SHAM-control, aortic banding without treatment (AB-Ctrl) and aortic banding with telmisartan treatment (AB-Telmi; 5mg/kg/day for 8 weeks). Echocardiography, hemodynamics, and pathology were performed to assess LVH. Left ventricular myocardium was sampled. The analysis of proteomic proteins from myocardium was performed by two-dimensional gel electrophoresis and MALDI-TOF-MS. In AB-Ctrl, heart rate, systolic arterial blood pressure, diastolic blood pressure, left ventricular end systolic pressure, interventricular septal thickness at diastole, posterior wall thickness in diastole, heart weight (HW) and HW/body weight (BW) were increased, indicating that both hypertension and LVH developed. Telmisartan prevented hypertension and LVH. Concurrently, among numerous proteins, there were 17 that were differentially expressed among hypertrophic hearts, normal hearts, and the hearts where hypertrophic response was suppressed by ARB treatment. Primarily, proteins involved in cell structure, metabolism, stress and signal transduction exhibited up-regulations in LVH, providing cellular and molecular mechanism for hypertrophic development. These changes were prevented or greatly attenuated by telmisartan regimen. Interestingly, antioxidative-related heat shock protein 2 was detected neither in SHAM-Ctrl nor in AB-Ctrl, but in AB-Telmi. LVH is accompanied by series changes of protein expression. Both LVH and proteomic changes can be prevented by blockade of renin-angiotensin system with telmisartan. These protein alterations may constitute mechanistic pathways leading to hypertrophy development and experimental targets for novel therapeutic strategy.
Kralova, Eva; Doka, Gabriel; Pivackova, Lenka; Srankova, Jasna; Kuracinova, Kristina; Janega, Pavol; Babal, Pavel; Klimas, Jan; Krenek, Peter
2015-10-01
In view of previously reported increased capacity for nitric oxide production, we suggested that l-arginine (ARG), the nitric oxide synthase (NOS) substrate, supplementation would improve cardiac function in isoproterenol (ISO)-induced heart failure. Male Wistar rats were treated with ISO for 8 days (5 mg/kg/day, i.p.) or vehicle. ARG was given to control (ARG) and ISO-treated (ISO+ARG) rats in water (0.4 g/kg/day). ISO administration was associated with 40% mortality, ventricular hypertrophy, decreased heart rate, left ventricular dysfunction, fibrosis and ECG signs of ischaemia. RT-PCR showed increased mRNA levels of cardiac hypertrophy marker atrial natriuretic peptide, but not BNP, decreased expression of myosin heavy chain isoform MYH6 and unaltered expression of pathological MYH7. ISO increased the protein levels of endothelial nitric oxide synthase, but at the same time it markedly up-regulated mRNA and protein levels of gp91phox, a catalytical subunit of superoxide-producing NADPH oxidase. Fibrosis was markedly increased by ISO. ARG treatment moderately ameliorated left ventricular dysfunction, but was without effect on cardiac hypertrophy and fibrosis. Combination of ISO and ARG led to a decrease in cav-1 expression, a further increase in MYH7 expression and a down-regulation of MYH6 that inversely correlated with gp91phox mRNA levels. Although ARG, at least partially, improved ISO-impaired basal left ventricular systolic function, it failed to reduce cardiac hypertrophy, fibrosis, oxidative stress and mortality. The protection of contractile performance might be related to increased capacity for nitric oxide production and the up-regulation of MYH7 which may compensate for the marked down-regulation of the major MYH6 isoform. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).
Gebker, Rolf; Mirelis, Jesus G; Jahnke, Cosima; Hucko, Thomas; Manka, Robert; Hamdan, Ashraf; Schnackenburg, Bernhard; Fleck, Eckart; Paetsch, Ingo
2010-09-01
The purpose of this study was to determine the influence of left ventricular (LV) hypertrophy and geometry on the diagnostic accuracy of wall motion and additional perfusion imaging during high-dose dobutamine/atropine stress magnetic resonance for the detection of coronary artery disease. Combined dobutamine stress magnetic resonance (DSMR)-wall motion and DSMR-perfusion imaging was performed in a single session in 187 patients scheduled for invasive coronary angiography. Patients were classified into 4 categories on the basis of LV mass (normal, ≤ 81 g/m(2) in men and ≤ 62 g/m(2) in women) and relative wall thickness (RWT) (normal, <0.45) as follows: normal geometry (normal mass, normal RWT), concentric remodeling (normal mass, increased RWT), concentric hypertrophy (increased mass, increased RWT), and eccentric hypertrophy (increased mass, normal RWT). Wall motion and perfusion images were interpreted sequentially, with observers blinded to other data. Significant coronary artery disease was defined as ≥ 70% stenosis. In patients with increased LV concentricity (defined by an RWT ≥ 0.45), sensitivity and accuracy of DSMR-wall motion were significantly reduced (63% and 73%, respectively; P<0.05) compared with patients without increased LV concentricity (90% and 88%, respectively; P<0.05). Although accuracy of DSMR-perfusion was higher than that of DSMR-wall motion in patients with concentric hypertrophy (82% versus 71%; P < 0.05), accuracy of DSMR-wall motion was superior to DSMR-perfusion (90% versus 85%; P < 0.05) in patients with eccentric hypertrophy. The accuracy of DSMR-wall motion is influenced by LV geometry. In patients with concentric remodeling and concentric hypertrophy, additional first-pass perfusion imaging during high-dose dobutamine stress improves the diagnostic accuracy for the detection of coronary artery disease.
Ankylosing Spondylitis Is Associated with Increased Prevalence of Left Ventricular Hypertrophy.
Midtbø, Helga; Gerdts, Eva; Berg, Inger Jorid; Rollefstad, Silvia; Jonsson, Roland; Semb, Anne Grete
2018-06-01
Ankylosing spondylitis (AS) is associated with increased risk for cardiovascular disease (CVD). Left ventricular (LV) hypertrophy is a strong precursor for clinical CVD. The aim of our study was to assess whether having AS was associated with increased prevalence of LV hypertrophy. Clinical and echocardiographic data from 139 AS patients and 126 age- and sex-matched controls was used. LV mass was calculated according to guidelines and indexed to height 2.7 . LV hypertrophy was considered present if LV mass index was > 49.2 g/m 2.7 in men and > 46.7 g/m 2.7 in women. Patients with AS were on average 49 ± 12 years old, and 60% were men. The prevalence of hypertension (HTN; 35% vs 41%) and diabetes (5% vs 2%) was similar among patients and controls, while patients with AS had higher serum C-reactive protein level (CRP; p < 0.001). The prevalence of LV hypertrophy was higher in patients with AS compared to controls (15% vs 6%, p = 0.01). In multivariable logistic regression analysis, having AS was associated with OR 6.3 (95% CI 2.1-19.3, p = 0.001) of having LV hypertrophy independent of the presence of HTN, diabetes, and obesity. In multivariable linear regression analyses, having AS was also associated with higher LV mass (β 0.15, p = 0.007) after adjusting for CVD risk factors including sex, body mass index, systolic blood pressure, diabetes, and serum CRP (multiple R 2 = 0.41, p < 0.001). Having AS was associated with increased prevalence of LV hypertrophy independent of CVD risk factors. This finding strengthens the indication for thorough CVD risk assessment in patients with AS.
Qiliqiangxin Affects L Type Ca2+ Current in the Normal and Hypertrophied Rat Heart
Wei, Yidong; Liu, Xiaoyu; Hou, Lei; Che, Wenliang; The, Erlinda; Jhummon, Muktanand Vikash
2012-01-01
Qiliqiangxin capsule is newly developed Chinese patent drug and proved to be effective and safe for the treatment of patients with chronic heart failure. We compared the effects of different dose Qiliqiangxin on L type Ca2+ current (I Ca-L) between normal and hypertrophied myocytes. A total of 40 healthy Sprague—Dawley rats were used in the study. The rats were randomly divided into two groups (control group and hypertrophy group). Cardiac hypertrophy was induced by pressure overload produced by partial ligation of the abdominal aorta. The control group was the sham-operated group. After 1 month, cardiac ventricular myocytes were isolated from the hearts of rats. Ventricular myocytes were exposed to 10 and 50 μmol/L Qiliqiangxin, and whole cell patch-clamp technique was used to study the effects of Qiliqiangxin on I Ca-L. The current densities of I Ca-L were similar in control group (−12.70 ± 0.53 pA/pF, n = 12) and in hypertrophy group (−12.39 ± 0.62 pA/pF, n = 10). They were not statistically significant. 10 and 50 μmol/L Qiliqiangxin can decrease I Ca-L peak current 48.6%±16.8% and 59.0%±4.4% in control group. However, the peak current was only reduced 16.73%±8.03% by 50 μmol/L Qiliqiangxin in hypertrophied myocytes. The inhibited action of Qiliqiangxin on I Ca-L of hypertrophy group was lower than in control group. Qiliqiangxin affected L-type Ca2+ channel and blocked I Ca-L, as well as affected cardiac function finally. Qiliqiangxin has diphasic action that is either class IV antiarrhythmic agent or the agent of effect cardiac function. PMID:22536279
Ramos-Kuri, Manuel; Rapti, Kleopatra; Mehel, Hind; Zhang, Shihong; Dhandapany, Perundurai S.; Liang, Lifan; García-Carrancá, Alejandro; Bobe, Regis; Fischmeister, Rodolphe; Adnot, Serge; Lebeche, Djamel; Hajjar, Roger J.; Lipskaia, Larissa; Chemaly, Elie R.
2015-01-01
The importance of the oncogene Ras in cardiac hypertrophy is well appreciated. The hypertrophic effects of the constitutively active mutant Ras-Val12 are revealed by clinical syndromes due to the Ras mutations and experimental studies. We examined the possible anti-hypertrophic effect of Ras inhibition in vitro using rat neonatal cardiomyocytes (NRCM) and in vivo in the setting of pressure-overload left ventricular (LV) hypertrophy (POH) in rats. Ras functions were modulated via adenovirus directed gene transfer of active mutant Ras-Val12 or dominant negative mutant N17-DN-Ras (DN-Ras). Ras-Val12 expression in vitro activates NFAT resulting in pro-hypertrophic and cardio-toxic effects on NRCM beating and Z-line organization. In contrast, the DN-Ras was antihypertrophic on NRCM, inhibited NFAT and exerted cardio-protective effects attested by preserved NRCM beating and Z line structure. Additional experiments with silencing H-Ras gene strategy corroborated the antihypertrophic effects of siRNA-H-Ras on NRCM. In vivo, with the POH model, both Ras mutants were associated with similar hypertrophy two weeks after simultaneous induction of POH and Ras-mutant gene transfer. However, LV diameters were higher and LV fractional shortening lower in the Ras-Val12 group compared to control and DN-Ras. Moreover, DN-Ras reduced the cross-sectional area of cardiomyocytes in vivo, and decreased the expression of markers of pathologic cardiac hypertrophy. In isolated adult cardiomyocytes after 2 weeks of POH and Ras-mutant gene transfer, DN-Ras improved sarcomere shortening and calcium transients compared to Ras-Val12. Overall, DN-Ras promotes a more physiological form of hypertrophy, suggesting an interesting therapeutic target for pathological cardiac hypertrophy. PMID:26260012
Pereira, Leila Maria Meirelles; Mandarim-de-Lacerda, Carlos Alberto
2001-01-01
Forty male Wistar rats were separated into four groups of ten rats each (control and other three groups that have received nitric oxide (NO) synthesis inhibitor L-NAME) but the last two groups have concomitantly received antihypertensive drugs (Enalapril and Verapamil). After 40 days of experimentation, the heart and the ventricles were measured. The optical disector was used for the calculation of numerical density of the cardiomyocytes (Nv[c]). The left ventricular myocytes number (N[c]) was calculated as the product of Nv[c] and the left ventricular myocardium volume (LVMV) that was determined by using the Scherle's method. In the L-NAME group the blood pressure (BP) had a significant weekly increment. In the enalapril and the verapamil groups, BP increased in the first two weeks, but decreased in the following weeks. The LVMV increased in the L-NAME rats and decreased in the enalapril and verapamil animals. The Nv[c] and N[c] decreased in the L-NAME rats but the verapamil and enalapril treatments maintained the Nv[c] close to the control group. In conclusion, the left ventricular hypertrophy and the significant decrease of the left ventricular cardiomyocyte number caused by the NO synthesis inhibition are efficiently prevented with the use of enalapril and verapamil. PMID:11454102
Cho, Yang Hyun; Deo, Salil V; Topilsky, Yan; Grogan, Martha A; Park, Soon J
2012-03-01
Apical hypertrophy is a rare variant of hypertropic cardiomyopathy. These patients may present with end-stage congestive heart failure subsequent to long standing diastolic dysfunction. We report the technique for left ventricular assist device insertion in a patient with previous apical myectomy for hypertrophic cardiomyopathy. © 2012 Wiley Periodicals, Inc.
Yan, Ling; Bowman, Marion A Hofmann
Cardiovascular disease including left ventricular hypertrophy, diastolic dysfunction and ectopic valvular calcification are common in patients with chronic kidney disease (CKD). Both S100A12 and fibroblast growth factor 23 (FGF23) have been identified as biomarkers of cardiovascular morbidity and mortality in patients with CKD. We tested the hypothesis that human S100/calgranulin would accelerate cardiovascular disease in mice subjected to CKD. This review paper focuses on S100 proteins and their receptor for advanced glycation end products (RAGE) and summarizes recent findings obtained in novel developed transgenic hBAC-S100 mice that express S100A12 and S100A8/9 proteins. A bacterial artificial chromosome of the human S100/calgranulin gene cluster containing the genes and regulatory elements for S100A8, S100A9 and S100A12 was expressed in C57BL/6J mice (hBAC-S100). CKD was induced by ureteral ligation, and hBAC-S100 mice and WT mice were studied after 10 weeks of chronic uremia. hBAC-S100 mice with CKD showed increased FGF23 in the heart, left ventricular hypertrophy (LVH), diastolic dysfunction, focal cartilaginous metaplasia and calcification of the mitral and aortic valve annulus together with aortic valve sclerosis. This phenotype was not observed in WT mice with CKD or in hBAC-S100 mice lacking RAGE with CKD, suggesting that the inflammatory milieu mediated by S100/RAGE promotes pathological cardiac hypertrophy in CKD. In vitro, inflammatory stimuli including IL-6, TNFα, LPS, or serum from hBAC-S100 mice up regulated FGF23 mRNA and protein in primary murine neonatal and adult cardiac fibroblasts. Taken together, our study shows that myeloid-derived human S100/calgranulin is associated with the development of cardiac hypertrophy and ectopic cardiac calcification in a RAGE dependent manner in a mouse model of CKD. We speculate that FGF23 produced by cardiac fibroblasts in response to cytokines may act in a paracrine manner to accelerate LVH and diastolic dysfunction in hBAC-S100 mice with CKD. We suggest that S100/RAGE-mediated chronic sustained systemic inflammation is linked to pathological cardiac remodeling via direct up regulation of FGF23 in cardiac fibroblasts, thereby providing a new mechanistic understanding for the common association between CKD, diabetes, metabolic syndrome, or hypertension with left ventricular hypertrophy with diastolic dysfunction.
Verma, Anil; Meris, Alessandra; Skali, Hicham; Ghali, Jalal K; Arnold, J Malcolm O; Bourgoun, Mikhail; Velazquez, Eric J; McMurray, John J V; Kober, Lars; Pfeffer, Marc A; Califf, Robert M; Solomon, Scott D
2008-09-01
This study sought to understand prognostic implications of increased baseline left ventricular (LV) mass and geometric patterns in a high risk acute myocardial infarction. The LV hypertrophy and alterations in LV geometry are associated with an increased risk of adverse cardiovascular events. Quantitative echocardiographic analyses were performed at baseline in 603 patients from the VALIANT (VALsartan In Acute myocardial iNfarcTion) echocardiographic study. The left ventricular mass index (LVMi) and relative wall thickness (RWT) were calculated. Patients were classified into 4 mutually exclusive groups based on RWT and LVMi as follows: normal geometry (normal LVMi and normal RWT), concentric remodeling (normal LVMi and increased RWT), eccentric hypertrophy (increased LVMi and normal RWT), and concentric hypertrophy (increased LVMi and increased RWT). Cox proportional hazards models were used to evaluate the relationships among LVMi, RWT, LV geometry, and clinical outcomes. Mean LVMi and RWT were 98.8 +/- 28.4 g/m(2) and 0.38 +/- 0.08. The risk of death or the composite end point of death from cardiovascular causes, reinfarction, heart failure, stroke, or resuscitation after cardiac arrest was lowest for patients with normal geometry, and increased with concentric remodeling (hazard ratio [HR]: 3.0; 95% confidence interval [CI]: 1.9 to 4.9), eccentric hypertrophy (HR: 3.1; 95% CI: 1.9 to 4.8), and concentric hypertrophy (HR: 5.4; 95% CI: 3.4 to 8.5), after adjusting for baseline covariates. Also, baseline LVMi and RWT were associated with increased mortality and nonfatal cardiovascular outcomes (HR: 1.22 per 10 g/m(2) increase in LVMi; 95% CI: 1.20 to 1.30; p < 0.001) (HR: 1.60 per 0.1-U increase in RWT; 95% CI: 1.30 to 1.90; p < 0.001). Increased risk associated with RWT was independent of LVMi. Increased baseline LV mass and abnormal LV geometry portend an increased risk for morbidity and mortality following high-risk myocardial infarction. Concentric LV hypertrophy carries the greatest risk of adverse cardiovascular events including death. Higher RWT was associated with an increased risk of cardiovascular complications after high-risk myocardial infarction.
Liang, B; Leenen, F H H
2007-01-01
Background and purpose: In Dahl S rats, high salt increases activity of the tissue renin-angiotensin-aldosterone system (RAAS) in the CNS, heart and kidneys. Here, we assessed the effects of chronic angiotensin converting enzyme (ACE) inhibition on salt-induced hypertension and cardiovascular and renal hypertrophy and fibrosis, relative to the extent of ACE blockade. Experimental approach: From 4.5 weeks of age, Dahl S rats received either the lipophilic ACE inhibitor trandolapril (1 or 5 mg kg-1 day-1) or the hydrophilic ACE inhibitor lisinopril (10 or 50 mg kg-1 day-1) and a high salt diet was started 0.5 week later. Treatments ended at 9 weeks of age. Key results: High salt diet markedly increased blood pressure (BP), decreased plasma angiotensin II and increased ACE binding densities in brain, heart, aorta and kidneys. Trandolapril and lisinopril prevented 50% of the increase in BP in light and dark period of the day. After the last doses, trandolapril decreased ACE densities by ∼80% in brain nuclei and heart and lisinopril by ∼60% in the brain and by ∼70% in the heart. The two ACE inhibitors prevented right ventricular hypertrophy and attenuated left ventricular hypertrophy but did not affect renal hypertrophy caused by high salt. Both drugs prevented high salt-induced fibrosis in heart, kidney and aorta. Conclusion and implication: As the ACE inhibitors could completely prevent tissue fibrosis and partially prevent tissue hypertrophy and hypertension, the tissue RAAS may play a critical role in salt-induced fibrosis, but a lesser role in the hypertrophy. PMID:17906684
Wang, Huan; Kwak, Dongmin; Fassett, John; Liu, Xiaohong; Yao, Wu; Weng, Xinyu; Xu, Xin; Xu, Yawei; Bache, Robert J; Mueller, Daniel L; Chen, Yingjie
2017-05-01
Inflammatory responses play an important role in the development of left ventricular (LV) hypertrophy and dysfunction. Recent studies demonstrated that increased T-cell infiltration and T-cell activation contribute to LV hypertrophy and dysfunction. Dendritic cells (DCs) are professional antigen-presenting cells that orchestrate immune responses, especially by modulating T-cell function. In this study, we investigated the role of bone marrow-derived CD11c + DCs in transverse aortic constriction (TAC)-induced LV fibrosis and hypertrophy in mice. We observed that TAC increased the number of CD11c + cells and the percentage of CD11c + MHCII + (major histocompatibility complex class II molecule positive) DCs in the LV, spleen and peripheral blood in mice. Using bone marrow chimeras and an inducible CD11c + DC ablation model, we found that depletion of bone marrow-derived CD11c + DCs significantly attenuated LV fibrosis and hypertrophy in mice exposed to 24 weeks of moderate TAC. CD11c + DC ablation significantly reduced TAC-induced myocardial inflammation as indicated by reduced myocardial CD45 + cells, CD11b + cells, CD8 + T cells and activated effector CD8 + CD44 + T cells in LV tissues. Moreover, pulsing of autologous DCs with LV homogenates from TAC mice promoted T-cell proliferation. These data indicate that bone marrow-derived CD11c + DCs play a maladaptive role in hemodynamic overload-induced cardiac inflammation, hypertrophy and fibrosis through the presentation of cardiac self-antigens to T cells.
Singh, Amrit Pal; Singh, Randhir; Krishan, Pawan
2015-04-01
Fibrates are peroxisome proliferator-activated receptor-α agonists and are clinically used for treatment of dyslipidemia and hypertriglyceridemia. Fenofibrate is reported as a cardioprotective agent in various models of cardiac dysfunction; however, limited literature is available regarding the role of gemfibrozil as a possible cardioprotective agent, especially in a non-obese model of cardiac remodelling. The present study investigated the role of gemfibrozil against partial abdominal aortic constriction-induced cardiac hypertrophy in rats. Cardiac hypertrophy was induced by partial abdominal aortic constriction in rats and they survived for 4 weeks. The cardiac hypertrophy was assessed by measuring left ventricular weight to body weight ratio, left ventricular wall thickness, and protein and collagen content. The oxidative stress in the cardiac tissues was assessed by measuring thiobarbituric acid-reactive substances, superoxide anion generation, and reduced glutathione level. The haematoxylin-eosin and picrosirius red staining was used to observe cardiomyocyte diameter and collagen deposition, respectively. Moreover, serum levels of cholesterol, high-density lipoproteins, triglycerides, and glucose were also measured. Gemfibrozil (30 mg/kg, p.o.) was administered since the first day of partial abdominal aortic constriction and continued for 4 weeks. The partial abdominal aortic constriction-induced cardiac oxidative stress and hypertrophy are indicated by significant change in various parameters used in the present study that were ameliorated with gemfibrozil treatment in rats. No significant change in serum parameters was observed between various groups used in the present study. It is concluded that gemfibrozil ameliorates partial abdominal aortic constriction-induced cardiac oxidative stress and hypertrophy and in rats.
Towe, Eric; Sharma, Saurabh; Geske, Jeffrey; Ackerman, Michael J
2015-01-01
A woman in her late 50s experienced a witnessed, sudden out of hospital cardiac arrest. Initial workup included coronary angiography, transthoracic echocardiogram and a CT scan of the chest to rule out pulmonary embolus. She was subsequently discharged home without an implantable cardioverter defibrillator (ICD) or a life vest. On follow-up at another facility, an ICD was placed and a Holter monitor showed no ventricular ectopy. Further transthoracic echocardiographic images were obtained, which were suggestive of apical hypertrophic cardiomyopathy. A limited transthoracic echocardiogram with contrast was performed, which did not elucidate the hypertrophy. However, eccentric left ventricular apical wall hypertrophy was visualised by a coronary CT scan. PMID:26153133
Rajapakse, Niwanthi W; Johnston, Tamara; Kiriazis, Helen; Chin-Dusting, Jaye P; Du, Xiao-Jun; Kaye, David M
2015-07-01
What is the central question of this study? What is the potential role of endothelial NO production via overexpression of the l-arginine transporter, CAT1, as a mitigator of cardiac hypertrophy? What is the main finding and its importance? Augmentation of endothelium-specific l-arginine transport via CAT1 can attenuate pressure-overload-dependent cardiac hypertrophy and fibrosis. Our findings support the conclusion that interventions that improve endothelial l-arginine transport may provide therapeutic utility in the setting of myocardial hypertrophy. Such modifications may be introduced by exercise training or locally delivered gene therapy, but further experimental and clinical studies are required. Endothelial dysfunction has been postulated to play a central role in the development of cardiac hypertrophy, probably as a result of reduced NO bioavailability. We tested the hypothesis that increased endothelial NO production, mediated by increased l-arginine transport, could attenuate pressure-overload-induced cardiac hypertrophy. Echocardiography and blood pressure measurements were performed 15 weeks after transverse aortic constriction (TAC) in wild-type (WT) mice (n = 12) and in mice with endothelium-specific overexpression of the l-arginine transporter, CAT1 (CAT+; n = 12). Transverse aortic constriction induced greater increases in heart weight to body weight ratio in WT (by 47%) than CAT+ mice (by 25%) compared with the respective controls (P ≤ 0.05). Likewise, the increase in left ventricular wall thickness induced by TAC was significantly attenuated in CAT+ mice (P = 0.05). Cardiac collagen type I mRNA expression was greater in WT mice with TAC (by 22%; P = 0.03), but not in CAT+ mice with TAC, compared with the respective controls. Transverse aortic constriction also induced lesser increases in β-myosin heavy chain mRNA expression in CAT+ mice compared with WT (P ≤ 0.05). Left ventricular systolic pressure after TAC was 36 and 39% greater in WT and CAT+ mice, respectively, compared with the respective controls (P ≤ 0.001). Transverse aortic constriction had little effect on left ventricular end-diastolic pressure in both genotypes. Taken together, these data indicate that augmenting endothelial function by overexpression of l-arginine transport can attenuate pressure-overload-induced cardiac hypertrophy. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.
Molina, Ezequiel J; Palma, Jon; Gupta, Dipin; Gaughan, John P; Houser, Steven; Macha, Mahender
2009-12-01
In a rat model of left ventricular pressure overload hypertrophy with biventricular failure, we studied the effects of intracoronary delivery of mesenchymal stem cells (MCS) upon right ventricular hemodynamic performance, profiles of local inflammation and apoptosis, and determinants of extracellular matrix remodeling. Sprague-Dawley rats underwent aortic banding and were followed by echocardiography. After a decrease in left ventricular fractional shortening of 25% from the baseline (relative 50% reduction), animals were randomized to an intracoronary injection of MSC (n=28) or PBS (n=20). Right ventricular hemodynamic assessment and measurement of local inflammatory markers, proapoptotic factors, and determinants of extracellular matrix remodeling were performed on post-transplantation day 7, 14, 21 or 28. MSC injection improved right ventricular systolic function in the MSC group compared to the control group (mean+/-SD, max dP/dt 772+/-272 mm Hg/s vs. 392+/-132 at 28 days, P<0.01). Diastolic function was similarly improved (mean+/-SD, max -dP/dt -558+/-171 mm Hg/s vs. -327+/-131 at 28 days, P<0.05). Right ventricular levels of IL-1, IL-6, TNF-alpha, bax, bak and p38 were significantly decreased in the MSC treated animals. Expression of MMP-3, MMP-6, MMP-9, TIMP-1 and TIMP-3 declined in the MSC group compared with controls after 28 days. In this model of left ventricular pressure overload hypertrophy and biventricular failure, intracoronary delivery of MSC was associated with an improvement in the right ventricular hemodynamic performance, profiles of local inflammation and apoptosis, and determinants of extracellular matrix remodeling.
Leischik, Roman; Spelsberg, Norman; Niggemann, Hiltrud; Dworrak, Birgit; Tiroch, Klaus
2014-01-01
Background : Exercise-induced arterial hypertension (EIAH) leads to myocardial hypertrophy and is associated with a poor prognosis. EIAH might be related to the “cardiac fatigue” caused by endurance training. The goal of this study was to examine whether there is any relationship between EIAH and left ventricular hypertrophy in Ironman-triathletes. Methods: We used echocardiography and spiroergometry to determine the left ventricular mass (LVM), the aerobic/anaerobic thresholds and the steady-state blood pressure of 51 healthy male triathletes. The main inclusion criterion was the participation in at least one middle or long distance triathlon. Results: When comparing triathletes with LVM <220g and athletes with LVM >220g there was a significant difference between blood pressure values (BP) at the anaerobic threshold (185.2± 21.5 mmHg vs. 198.8 ±22.3 mmHg, p=0.037). The spiroergometric results were: maximum oxygen uptake (relative VO 2max) 57.3 ±7.5ml/min/kg vs. 59.8±9.5ml/min/kg (p=ns). Cut-point analysis for the relationship of BP >170 mmHg at the aerobic threshold and the probability of LVM >220g showed a sensitivity of 95.8%, a specificity of 33.3%, with a positive predictive value of 56.8 %, a good negative predictive value of 90%. The probability of LVM >220g increased with higher BP during exercise (OR: 1.027, 95% CI 1.002-1.052, p= 0.034) or with higher training volume (OR: 1.23, 95% CI 1.04 -1.47, p = 0.019). Echocardiography showed predominantly concentric remodelling, followed by concentric hypertrophy. Conclusion: Significant left ventricular hypertrophy with LVM >220g is associated with higher arterial blood pressure at the aerobic or anaerobic threshold. The endurance athletes with EIAH may require a therapeutic intervention to at least prevent extensive stiffening of the heart muscle and exercise-induced cardiac fatigue. PMID:25132960
Frentzou, Georgia A; Drinkhill, Mark J; Turner, Neil A; Ball, Stephen G; Ainscough, Justin F X
2015-08-01
Cardiac dysfunction is commonly associated with high-blood-pressure-induced cardiomyocyte hypertrophy, in response to aberrant renin-angiotensin system (RAS) activity. Ensuing pathological remodelling promotes cardiomyocyte death and cardiac fibroblast activation, leading to cardiac fibrosis. The initiating cellular mechanisms that underlie this progressive disease are poorly understood. We previously reported a conditional mouse model in which a human angiotensin II type-I receptor transgene (HART) was expressed in differentiated cardiomyocytes after they had fully matured, but not during development. Twelve-month-old HART mice exhibited ventricular dysfunction and cardiomyocyte hypertrophy with interstitial fibrosis following full receptor stimulation, without affecting blood pressure. Here, we show that chronic HART activity in young adult mice causes ventricular dysfunction without hypertrophy, fibrosis or cardiomyocyte death. Dysfunction correlated with reduced expression of pro-hypertrophy markers and increased expression of pro-angiogenic markers in the cardiomyocytes experiencing increased receptor load. This stimulates responsive changes in closely associated non-myocyte cells, including the downregulation of pro-angiogenic genes, a dampened inflammatory response and upregulation of Tgfβ. Importantly, this state of compensated dysfunction was reversible. Furthermore, increased stimulation of the receptors on the cardiomyocytes caused a switch in the secondary response from the non-myocyte cells. Progressive cardiac remodelling was stimulated through hypertrophy and death of individual cardiomyocytes, with infiltration, proliferation and activation of fibroblast and inflammatory cells, leading to increased angiogenic and inflammatory signalling. Together, these data demonstrate that a state of pre-hypertrophic compensated dysfunction can exist in affected individuals before common markers of heart disease are detectable. The data also suggest that there is an initial response from the housekeeping cells of the heart to signals emanating from distressed neighbouring cardiomyocytes to suppress those changes most commonly associated with progressive heart disease. We suggest that the reversible nature of this state of compensated dysfunction presents an ideal window of opportunity for personalised therapeutic intervention. © 2015. Published by The Company of Biologists Ltd.
Leischik, Roman; Spelsberg, Norman; Niggemann, Hiltrud; Dworrak, Birgit; Tiroch, Klaus
2014-01-01
Background : Exercise-induced arterial hypertension (EIAH) leads to myocardial hypertrophy and is associated with a poor prognosis. EIAH might be related to the "cardiac fatigue" caused by endurance training. The goal of this study was to examine whether there is any relationship between EIAH and left ventricular hypertrophy in Ironman-triathletes. We used echocardiography and spiroergometry to determine the left ventricular mass (LVM), the aerobic/anaerobic thresholds and the steady-state blood pressure of 51 healthy male triathletes. The main inclusion criterion was the participation in at least one middle or long distance triathlon. When comparing triathletes with LVM <220g and athletes with LVM >220g there was a significant difference between blood pressure values (BP) at the anaerobic threshold (185.2± 21.5 mmHg vs. 198.8 ±22.3 mmHg, p=0.037). The spiroergometric results were: maximum oxygen uptake (relative VO 2max) 57.3 ±7.5ml/min/kg vs. 59.8±9.5ml/min/kg (p=ns). Cut-point analysis for the relationship of BP >170 mmHg at the aerobic threshold and the probability of LVM >220g showed a sensitivity of 95.8%, a specificity of 33.3%, with a positive predictive value of 56.8 %, a good negative predictive value of 90%. The probability of LVM >220g increased with higher BP during exercise (OR: 1.027, 95% CI 1.002-1.052, p= 0.034) or with higher training volume (OR: 1.23, 95% CI 1.04 -1.47, p = 0.019). Echocardiography showed predominantly concentric remodelling, followed by concentric hypertrophy. Significant left ventricular hypertrophy with LVM >220g is associated with higher arterial blood pressure at the aerobic or anaerobic threshold. The endurance athletes with EIAH may require a therapeutic intervention to at least prevent extensive stiffening of the heart muscle and exercise-induced cardiac fatigue.
... of Privacy Practices Notice of Nondiscrimination Manage Cookies Advertising Mayo Clinic is a not-for-profit organization and proceeds from Web advertising help support our mission. Mayo Clinic does not ...
Peters, T H; Sharma, H S; Yilmaz, E; Bogers, A J
1999-06-30
One of the main features in human tetralogy of Fallot (TF) is right ventricular hypertrophy (RVH) due to pressure (sub-pulmonary stenosis) and volume overload (ventricular septal defect). Currently, primary correction at a young age is the treatment of choice. To unravel the role of extracellular matrix in RVH, we examined myocardial expression of collagens and fibronectin in TF patients with primary correction (TF1, age 0.7 +/- 0.2 yr.), secondary surgery (TF2, age 36.9 +/- 4.6 yr), and in age-matched control patients. Sirius red staining quantified by video imaging showed significantly increased interstitial staining for collagens in both TF1 and TF2 groups as compared to respective controls. Fibronectin was expressed in extracellular spaces, perivascular regions, and in some cardiomyocytes. Quantitative analysis of fibronectin revealed increased expression in only TF1 group as compared to respective control. Our results indicate an increased amount of myocardial extracellular matrix deposition as a sign of fibrosis during RVH in patients with TF.
Passive stiffness of pressure-induced hypertrophied cat myocardium.
Williams, J F; Potter, R D
1981-07-01
The effect of myocardial hypertrophy on passive stiffness was determined from the stress (sigma)-strain relationship of right ventricular papillary muscles from 18 pulmonary artery-banded and 21 non-banded cats. By use of Lagrangian strain, (1-lo)lo is initial muscle length, and instantaneous stress elastic constants beta and alpha were calculated from the equation sigma = alpha(ebeta epsilon - 1). Elastic stiffness (d sigma/d epsilon) was determined from the formula d sigma/d epsilon = beta alpha + alpha beta. Banding produced an average increase in RV mass of 70%. Beta averaged 14.2 +/- 0.9 (SEM) and 16.0 +/- 0.8 in the non-hypertrophied and hypertrophied muscles, respectively (NS). However, elastic stiffness was significantly greater in hypertrophied muscles over the entire stress range. Contractile function varied widely among hypertrophied muscles but was not related to changes in stiffness. Thus, moderate degrees of pressure-induced hypertrophy are associated with a modest increase in the passive stiffness properties of the muscle, independent of changes in contractile function.
Dhahri, Wahiba; Drolet, Marie-Claude; Roussel, Elise; Couet, Jacques; Arsenault, Marie
2014-09-24
The composition of a diet can influence myocardial metabolism and development of left ventricular hypertrophy (LVH). The impact of a high-fat diet in chronic left ventricular volume overload (VO) causing eccentric LVH is unknown. This study examined the effects of chronic ingestion of a high-fat diet in rats with chronic VO caused by severe aortic valve regurgitation (AR) on LVH, function and on myocardial energetics and survival. Male Wistar rats were divided in four groups: Shams on control or high-fat (HF) diet (15 rats/group) and AR rats fed with the same diets (ARC (n = 56) and ARHF (n = 32)). HF diet was started one week before AR induction and the protocol was stopped 30 weeks later. As expected, AR caused significant LV dilation and hypertrophy and this was exacerbated in the ARHF group. Moreover, survival in the ARHF group was significantly decreased compared the ARC group. Although the sham animals on HF also developed significant obesity compared to those on control diet, this was not associated with heart hypertrophy. The HF diet in AR rats partially countered the expected shift in myocardial energy substrate preference usually observed in heart hypertrophy (from fatty acids towards glucose). Systolic function was decreased in AR rats but HF diet had no impact on this parameter. The response to HF diet of different fatty acid oxidation markers as well as the increase in glucose transporter-4 translocation to the plasma membrane compared to ARC was blunted in AR animals compared to those on control diet. HF diet for 30 weeks decreased survival of AR rats and worsened eccentric hypertrophy without affecting systolic function. The expected adaptation of myocardial energetics to volume-overload left ventricle hypertrophy in AR animals seemed to be impaired by the high-fat diet suggesting less metabolic flexibility.
Cardiac tissue Doppler imaging in sports medicine.
Krieg, Anne; Scharhag, Jürgen; Kindermann, Wilfried; Urhausen, Axel
2007-01-01
The differentiation of training-induced cardiac adaptations from pathological conditions is a key issue in sports cardiology. As morphological features do not allow for a clear delineation of early stages of relevant pathologies, the echocardiographic evaluation of left ventricular function is the technique of first choice in this regard. Tissue Doppler imaging (TDI) is a relatively recent method for the assessment of cardiac function that provides direct, local measurements of myocardial velocities throughout the cardiac cycle. Although it has shown a superior sensitivity in the detection of ventricular dysfunction in clinical and experimental studies, its application in sports medicine is still rare. Besides technical factors, this may be due to a lack in consensus on the characteristics of ventricular function in relevant conditions. For more than two decades there has been an ongoing debate on the existence of a supernormal left ventricular function in athlete's heart. While results from traditional echocardiography are conflicting, TDI studies established an improved diastolic function in endurance-trained athletes with athlete's heart compared with controls.The influence of anabolic steroids on cardiac function also has been investigated by standard echocardiographic techniques with inconsistent results. The only TDI study dealing with this topic demonstrated a significantly impaired diastolic function in bodybuilders with long-term abuse of anabolic steroids compared with strength-trained athletes without abuse of anabolic steroids and controls, respectively.Hypertrophic cardiomyopathy is the most frequent cause of sudden death in young athletes. However, in its early stages, it is difficult to distinguish from athlete's heart. By means of TDI, ventricular dysfunction in hypertrophic cardiomyopathy can be disclosed even before the development of left ventricular hypertrophy. Also, a differentiation of left ventricular hypertrophy due to hypertrophic cardiomyopathy or systemic hypertension is possible by TDI. Besides the evaluation of different forms of left ventricular hypertrophy, the diagnosis of myocarditis is also of particular importance in athletes. Today, it still requires myocardial biopsy. The analysis of focal disturbances in myocardial velocities might be a promising non-invasive method; however, systematic validation studies are lacking. An important future issue for the implementation of TDI into routine examination will be the standardisation of procedures and the establishment of significant reference values for the above-mentioned conditions. Innovative TDI parameters also merit further investigation.
Apical hypertrophy associated with rapid T wave inversion on the electrocardiogram.
Yamanari, H; Saito, D; Mikio, K; Nakamura, K; Nanba, T; Morita, H; Mizuo, K; Sato, T; Ohe, T
1995-01-01
A 53-year-old man who had no chest pain and no family history of heart disease demonstrated a rapid T wave change on an electrocardiogram, from a positive T wave to a giant negative T wave, within 1 year. Echocardiography showed no left ventricular hypertrophy before or after the T wave change. Cine-magnetic resonance imaging revealed focal apical hypertrophy after the appearance of the giant negative T wave. Although T wave inversions sometimes develop within a short period in patients with hypertrophic cardiomyopathy, they are rare in a patient without hypertension or chest pain.
Mouse models for the study of postnatal cardiac hypertrophy.
Del Olmo-Turrubiarte, A; Calzada-Torres, A; Díaz-Rosas, G; Palma-Lara, I; Sánchez-Urbina, R; Balderrábano-Saucedo, N A; González-Márquez, H; Garcia-Alonso, P; Contreras-Ramos, A
2015-06-01
The main objective of this study was to create a postnatal model for cardiac hypertrophy (CH), in order to explain the mechanisms that are present in childhood cardiac hypertrophy. Five days after implantation, intraperitoneal (IP) isoproterenol (ISO) was injected for 7 days to pregnant female mice. The fetuses were obtained at 15, 17 and 19 dpc from both groups, also newborns (NB), neonates (7-15 days) and young adults (6 weeks of age). Histopathological exams were done on the hearts. Immunohistochemistry and western blot demonstrated GATA4 and PCNA protein expression, qPCR real time the mRNA of adrenergic receptors (α-AR and β-AR), alpha and beta myosins (α-MHC, β-MHC) and GATA4. After the administration of ISO, there was no change in the number of offsprings. We observed significant structural changes in the size of the offspring hearts. Morphometric analysis revealed an increase in the size of the left ventricular wall and interventricular septum (IVS). Histopathological analysis demonstrated loss of cellular compaction and presence of left ventricular small fibrous foci after birth. Adrenergic receptors might be responsible for changing a physiological into a pathological hypertrophy. However GATA4 seemed to be the determining factor in the pathology. A new animal model was established for the study of pathologic CH in early postnatal stages.
Paffett, Michael L.; Lucas, Selita N.; Campen, Matthew J.
2011-01-01
Arterial remodeling contributes to the elevated pulmonary artery (PA) pressures and right ventricular hypertrophy seen in pulmonary hypertension (PH). Resveratrol, a sirtuin-1 (SIRT1) pathway activator, can prevent the development of PH in a commonly used animal model, but it is unclear whether it can reverse established PH pathophysiology. Furthermore, atrophic ubiquitin ligases, such as atrogin-1 and MuRF-1, are known to be induced by SIRT1 activators but have not been characterized in hypertrophic vascular disease. Therefore, we hypothesized that monocrotaline (MCT)-induced PH would attenuate atrophy pathways in the PA while, conversely, SIRT1 activation (resveratrol) would reverse indices of PH and restore atrophic gene expression. Thus, we injected Sprague-Dawley rats with MCT (50 mg/kg i.p.) or saline at Day 0, and then treated with oral resveratrol or sildenafil from days 28–42 post-MCT injection. Oral resveratrol attenuated established MCT-induced PH indices, including right ventricular systolic pressure, right ventricular hypertrophy, and medial thickening of intrapulmonary arteries. Resveratrol also normalized PA atrogin-1 mRNA expression, which was significantly reduced by MCT. In cultured human PA smooth muscle cells (hPASMC), resveratrol significantly inhibited PDGF-stimulated proliferation and cellular hypertrophy, which was also associated with improvements in atrogin-1 levels. In addition, SIRT1 inhibition augmented hPASMC proliferation, as assessed by DNA mass, and suppressed atrogin mRNA expression. These findings demonstrate an inverse relationship between indices of PH and PA atrogin expression that is SIRT1 dependent and may reflect a novel role for SIRT1 in PASMCs opposing cellular hypertrophy and proliferation. PMID:22146233
Toemen, L; Gishti, O; van Osch-Gevers, L; Steegers, E A P; Helbing, W A; Felix, J F; Reiss, I K M; Duijts, L; Gaillard, R; Jaddoe, V W V
2016-07-01
Maternal obesity may affect cardiovascular outcomes in the offspring. We examined the associations of maternal prepregnancy body mass index and gestational weight gain with childhood cardiac outcomes and explored whether these associations were explained by parental characteristics, infant characteristics or childhood body mass index. In a population-based prospective cohort study among 4852 parents and their children, we obtained maternal weight before pregnancy and in early, mid- and late pregnancy. At age 6 years, we measured aortic root diameter (cm) and left ventricular dimensions. We calculated left ventricular mass (g), left ventricular mass index (g m(-2.7)), relative wall thickness ((2 × left ventricular posterior wall thickness)/left ventricular diameter), fractional shorting (%), eccentric left ventricular hypertrophy and concentric remodeling. A one standard deviation score (SDS) higher maternal prepregnancy body mass index was associated with higher left ventricular mass (0.10 SDS (95% confidence interval (CI) 0.08, 0.13)), left ventricular mass index (0.06 SDS (95% CI 0.03, 0.09)) and aortic root diameter (0.09 SDS (95% CI 0.06, 0.12)), but not with relative wall thickness or fractional shortening. A one SDS higher maternal prepregnancy body mass index was associated with an increased risk of eccentric left ventricular hypertrophy (odds ratio 1.21 (95% CI 1.03, 1.41)), but not of concentric remodeling. When analyzing the effects of maternal weight in different periods simultaneously, only maternal prepregnancy weight and early pregnancy weight were associated with left ventricular mass, left ventricular mass index and aortic root diameter (P-values<0.05), independent of weight in other pregnancy periods. All observed associations were independent of parental and infant characteristics, but attenuated to non-significance after adjustment for childhood body mass index. Maternal prepregnancy body mass index and weight gain in early pregnancy are both associated with offspring cardiac structure in childhood, but these associations seem to be fully explained by childhood body mass index.
Xiong, Xingjiang; Yang, Xiaochen; Duan, Lian; Liu, Wei; Zhang, Yun; Liu, Yongmei; Wang, Pengqian; Li, Shengjie; Li, Xiaoke
2017-01-01
Chinese herbal medicine Bu-Shen-Jiang-Ya decoction (BSJYD) is reported to be beneficial for hypertension. Over expression of extracellular signal regulated kinases (ERK) pathway plays an important role in left ventricular hypertrophy (LVH). This study aimed to observe effects of BSJYD on LVH in spontaneously hypertensive rats (SHRs) and explore its possible mechanism on regulation of ERK pathway. Sixty 12-week-old SHRs were randomly allocated into 5 groups: BSJYD high dose group, middle dose group, low dose group, captopril group, and control group. Besides, a control group of Wistar-Kyoto rats was established. All rats were treated for 8 weeks. Systolic blood pressure (SBP), heart rate (HR), pathology, and left ventricular mass index (LVMI) were measured. Western blotting and Real-time PCR were used to assess the expressions of BDNF, Ras, ERK1/2, and c-fox levels. SBP and HR were significantly decreased compared with the control group and LVMI was markedly improved by BSJYD treatment in a dose-dependent manner. BSJYD inhibited the expression of BDNF, Ras, ERK1/2, and c-fox mRNA in LVH. In conclusion, BSJYD suppressed hypertension-induced cardiac hypertrophy by inhibiting the expression of ERK pathway. These changes in gene expression may be a possible mechanism by which BSJYD provides myocardial protection from hypertension. PMID:28225023
Cho, Jae Hyung; Selen, Mats A; Kocheril, Abraham G
2015-08-11
The 12-lead electrocardiographic screening for the prevention of sudden cardiac death in young competitive athletes is not cost-effective and thus not routinely recommended. We investigate whether a less expensive wireless electrocardiographic transmission device can be used to screen for the prevention of sudden cardiac death in this population. During pre-participation screening, twenty college football players underwent two electrocardiograms: a conventional 12-lead electrocardiogram and a wireless 9-lead electrocardiogram. We compared several electrocardiographic parameters (QRS duration, left ventricular hypertrophy using the Cornell voltage criteria and the Sokolow-Lyon criteria, ST deviation and corrected QT interval) to determine the correlation. The QRS duration, left ventricular hypertrophy using the Cornell voltage criteria and the Sokolow-Lyon criteria and corrected QT interval exhibited significant correlation between the two types of electrocardiograms (correlation coefficient 0.878, 0.630, 0.770 and 0.847, respectively with P values of 0.01, 0.003, 0.01 and 0.01, respectively). ST deviation in V1 was weakly correlated between the two types of electrocardiograms without statistical significance (correlation coefficient 0.360 with a P value of 0.119). Our newly developed wireless 9-lead electrocardiogram demonstrated significant correlations with a conventional 12-lead electrocardiogram in terms of QRS duration, left ventricular hypertrophy and corrected QT interval.
Peterson, Gail E; de Backer, Tine; Contreras, Gabriel; Wang, Xuelei; Kendrick, Cynthia; Greene, Tom; Appel, Lawrence J; Randall, Otelio S; Lea, Janice; Smogorzewski, Miroslaw; Vagaonescu, Tudor; Phillips, Robert A
2013-09-01
African Americans with hypertension are at high risk for adverse outcomes from cardiovascular and renal disease. Patients with stage 3 or greater chronic kidney disease have a high prevalence of left ventricular (LV) hypertrophy and diastolic dysfunction. Our goal was to study prospectively the relationships of LV mass and diastolic function with subsequent cardiovascular and renal outcomes in the African American Study of Kidney Disease and Hypertension cohort study. Of 691 patients enrolled in the cohort, 578 had interpretable echocardiograms and complete relevant clinical data. Exposures were LV hypertrophy and diastolic parameters. Outcomes were cardiovascular events requiring hospitalization or causing death; a renal composite outcome of doubling of serum creatinine or end-stage renal disease (censoring death); and heart failure. We found strong independent relationships between LV hypertrophy and subsequent cardiovascular (hazard ratio, 1.16; 95% confidence interval, 1.05-1.27) events, but not renal outcomes. After adjustment for LV mass and clinical variables, lower systolic tissue Doppler velocities and diastolic parameters reflecting a less compliant LV (shorter deceleration time and abnormal E/A ratio) were significantly (P<0.05) associated with future heart failure events. This is the first study to show a strong relationship among LV hypertrophy, diastolic parameters, and adverse cardiac outcomes in African Americans with hypertension and chronic kidney disease. These echocardiographic risk factors may help identify high-risk patients with chronic kidney disease for aggressive therapeutic intervention.
G protein-coupled receptor kinase 2 promotes cardiac hypertrophy
Tscheschner, Henrike; Gao, Erhe; Schumacher, Sarah M.; Yuan, Ancai; Backs, Johannes; Most, Patrick; Wieland, Thomas; Koch, Walter J.; Katus, Hugo A.; Raake, Philip W.
2017-01-01
The increase in protein activity and upregulation of G-protein coupled receptor kinase 2 (GRK2) is a hallmark of cardiac stress and heart failure. Inhibition of GRK2 improved cardiac function and survival and diminished cardiac remodeling in various animal heart failure models. The aim of the present study was to investigate the effects of GRK2 on cardiac hypertrophy and dissect potential molecular mechanisms. In mice we observed increased GRK2 mRNA and protein levels following transverse aortic constriction (TAC). Conditional GRK2 knockout mice showed attenuated hypertrophic response with preserved ventricular geometry 6 weeks after TAC operation compared to wild-type animals. In isolated neonatal rat ventricular cardiac myocytes stimulation with angiotensin II and phenylephrine enhanced GRK2 expression leading to enhanced signaling via protein kinase B (PKB or Akt), consecutively inhibiting glycogen synthase kinase 3 beta (GSK3β), such promoting nuclear accumulation and activation of nuclear factor of activated T-cells (NFAT). Cardiac myocyte hypertrophy induced by in vitro GRK2 overexpression increased the cytosolic interaction of GRK2 and phosphoinositide 3-kinase γ (PI3Kγ). Moreover, inhibition of PI3Kγ as well as GRK2 knock down prevented Akt activation resulting in halted NFAT activity and reduced cardiac myocyte hypertrophy. Our data show that enhanced GRK2 expression triggers cardiac hypertrophy by GRK2-PI3Kγ mediated Akt phosphorylation and subsequent inactivation of GSK3β, resulting in enhanced NFAT activity. PMID:28759639
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rabinovitch, M.A.; Rose, C.P.; Rouleau, J.L.
1987-12-01
In heart failure secondary to chronic mechanical overload, cardiac sympathetic neurons demonstrate depressed catecholamine synthetic and transport function. To assess the potential of sympathetic neuronal imaging for detection of depressed transport function, serial scintigrams were acquired after the intravenous administration of metaiodobenzylguanidine (/sup 131/I) to 13 normal dogs, 3 autotransplanted (denervated) dogs, 5 dogs with left ventricular failure, and 5 dogs with compensated left ventricular hypertrophy due to a surgical arteriovenous shunt. Nine dogs were killed at 14 hours postinjection for determination of metaiodobenzylguanidine (/sup 131/I) and endogenous norepinephrine content in left atrium, left ventricle, liver, and spleen. By 4more » hours postinjection, autotransplanted dogs had a 39% reduction in mean left ventricular tracer accumulation, reflecting an absent intraneuronal tracer pool. Failure dogs demonstrated an accelerated early mean left ventricular tracer efflux rate (26.0%/hour versus 13.7%/hour in normals), reflecting a disproportionately increased extraneuronal tracer pool. They also showed reduced late left ventricular and left atrial concentrations of tracer, consistent with a reduced intraneuronal tracer pool. By contrast, compensated hypertrophy dogs demonstrated a normal early mean left ventricular tracer efflux rate (16.4%/hour) and essentially normal late left ventricular and left atrial concentrations of tracer. Metaiodobenzylguanidine (/sup 131/I) scintigraphic findings reflect the integrity of the cardiac sympathetic neuronal transport system in canine mechanical-overload heart failure. Metaiodobenzylguanidine (/sup 123/I) scintigraphy should be explored as a means of early detection of mechanical-overload heart failure in patients.« less
Pritchett, Yili; Jemiai, Yannis; Chang, Yuchiao; Bhan, Ishir; Agarwal, Rajiv; Zoccali, Carmine; Wanner, Christoph; Lloyd-Jones, Donald; Cannata-Andía, Jorge B; Thompson, Taylor; Appelbaum, Evan; Audhya, Paul; Andress, Dennis; Zhang, Wuyan; Solomon, Scott; Manning, Warren J; Thadhani, Ravi
2011-04-01
Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies. PRIMO (Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease. Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis. If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making. The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.
FGF-23 and cardiovascular disease: review of literature.
Batra, Jasveen; Buttar, Rupinder Singh; Kaur, Pardeep; Kreimerman, Jacqueline; Melamed, Michal L
2016-12-01
This review examines associations between fibroblast growth factor 23 (FGF-23) and cardiovascular disease. FGF-23 is a hormone produced by osteocytes and osteoblasts that aids with phosphate excretion by the kidney and acts as a negative feedback regulator for activated vitamin D synthesis. Recent studies have found associations between elevated FGF-23 levels and a number of cardiovascular diseases, including hypertension, left ventricular hypertrophy, endothelial dysfunction, cardiovascular events and mortality. Recent studies have explored the possible effects of FGF-23 on the cardiovascular system. In animal and observational human studies, there is a link between elevated FGF-23 levels and multiple cardiovascular outcomes, including hypertension, left ventricular hypertrophy and cardiovascular events and mortality. Further studies are required to evaluate whether decreasing FGF-23 levels improves cardiovascular outcomes.
Epidemiology of left ventricular hypertrophy in hypertension: implications for the clinic.
Cramariuc, Dana; Gerdts, Eva
2016-08-01
Left ventricular hypertrophy (LVH) is a common complication to hypertension, indicating the presence of hypertensive heart disease, which puts the patient at a very high risk for subsequent clinical cardiovascular events like sudden cardiac death, stroke, myocardial infarction and heart failure. The epidemiology of LVH has changed in recent years as a consequence of the development of new diagnostic tools and demographic changes in hypertensive populations. Expert commentary: In individual hypertensive patients, the presence and type of LVH and associated systolic and diastolic myocardial dysfunction is modified by the co-presence of other cardiovascular risk factors and comorbidities and as well as activation of the reninangiotensin-aldosterone system and other molecular mechanisms involved in LVH pathophysiology. The purpose of this review is to give a clinical update on LVH in hypertension.
Molina, Ezequiel J; Palma, Jon; Gupta, Dipin; Torres, Denise; Gaughan, John P; Houser, Steven; Macha, Mahender
2008-02-01
In a rat model of pressure overload hypertrophy, we studied the effects of intracoronary delivery of mesenchymal stem cells on hemodynamic performance, exercise capacity, systemic inflammation, and left ventricular reverse remodeling. Sprague-Dawley rats underwent aortic banding and were followed up by echocardiographic scanning. After a decrease in fractional shortening of 25% from baseline, animals were randomized to intracoronary injection of mesenchymal stem cells (MSC group; n = 28) or phosphate-buffered saline solution (control group; n = 20). Hemodynamic and echocardiographic assessment, swim testing to exhaustion, and measurement of inflammatory markers were performed before the rats were humanely killed on postoperative day 7, 14, 21, or 28. Injection of mesenchymal stem cells improved systolic function in the MSC group compared with the control group (mean +/- standard deviation: maximum dP/dt 3048 +/- 230 mm Hg/s vs 2169 +/- 97 mm Hg/s at 21 days and 3573 +/- 741 mm Hg/s vs 1363 +/- 322 mm Hg/s at 28 days: P < .001). Time to exhaustion was similarly increased in the MSC group compared with controls (487 +/- 35 seconds vs 306 +/- 27 seconds at 28 days; P < .01). Serum levels of interleukins 1 and 6, tumor necrosis factor-alpha, and brain natriuretic peptide-32 were significantly decreased in animals treated with mesenchymal stem cells. Stem cell transplantation improved left ventricular fractional shortening at 21 and 28 days. Left ventricular end-systolic and end-diastolic diameters were also improved at 28 days. In this model of pressure overload hypertrophy, intracoronary delivery of mesenchymal stem cells during heart failure was associated with an improvement in hemodynamic performance, maximal exercise tolerance, systemic inflammation, and left ventricular reverse remodeling. This study suggests a potential role of this treatment strategy for the management of hypertrophic heart failure resulting from pressure overload.
Intensive Hemodialysis, Left Ventricular Hypertrophy, and Cardiovascular Disease.
McCullough, Peter A; Chan, Christopher T; Weinhandl, Eric D; Burkart, John M; Bakris, George L
2016-11-01
The prevalence of cardiovascular disease, including cardiac arrhythmia, coronary artery disease, cardiomyopathy, and valvular heart disease, is higher in hemodialysis (HD) patients than in the US resident population. Cardiovascular disease is the leading cause of death in HD patients and the principal discharge diagnosis accompanying 1 in 4 hospital admissions. Furthermore, the rate of hospital admissions for either heart failure or fluid overload is persistently high despite widespread use of β-blockers and renin-angiotensin system inhibitors and attempts to manage fluid overload with ultrafiltration. An important predictor of cardiovascular mortality and morbidity in dialysis patients is left ventricular hypertrophy (LVH). LVH is an adaptive response to increased cardiac work, typically caused by combined pressure and volume overload, resulting in cardiomyocyte hypertrophy and increased intercellular matrix. In new dialysis patients, the prevalence of LVH is 75%. Regression of LVH may reduce cardiovascular risk, including the incidence of heart failure, complications after myocardial infarction, and sudden arrhythmic death. Multiple randomized clinical trials show that intensive HD reduces left ventricular mass, a measure of LVH. Short daily and nocturnal schedules in the Frequent Hemodialysis Network trial reduced left ventricular mass by 14 (10%) and 11 (8%) g, respectively, relative to 3 sessions per week. Comparable efficacy was observed in an earlier trial of nocturnal HD. Intensive HD also improves cardiac rhythm. Clinical benefits have been reported only in observational studies. Daily home HD is associated with 17% and 16% lower risks for cardiovascular death and hospitalization, respectively; admissions for cerebrovascular disease, heart failure, and hypertensive disease, which collectively constitute around half of cardiovascular hospitalizations, were less likely with daily home HD. Relative to peritoneal dialysis, daily home HD is likewise associated with lower risk for cardiovascular hospitalization. In conclusion, intensive HD likely reduces left ventricular mass and may lead to lower risks for adverse cardiac events. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Yasuno, Shinji; Kuwahara, Koichiro; Kinoshita, Hideyuki; Yamada, Chinatsu; Nakagawa, Yasuaki; Usami, Satoru; Kuwabara, Yoshihiro; Ueshima, Kenji; Harada, Masaki; Nishikimi, Toshio; Nakao, Kazuwa
2013-12-01
Angiotensin II has been implicated in the development of various cardiovascular ailments, including cardiac hypertrophy and heart failure. The fact that inhibiting its signalling reduced the incidences of both sudden cardiac death and heart failure in several large-scale clinical trials suggests that angiotensin II is involved in increased cardiac arrhythmogenicity during the development of heart failure. However, because angiotensin II also promotes structural remodelling, including cardiomyocyte hypertrophy and cardiac fibrosis, it has been difficult to assess its direct contribution to cardiac arrhythmogenicity independently of the structural effects. We induced cardiac hypertrophy in wild-type (WT) and angiotensin II type 1a receptor knockout (AT1aR-KO) mice by transverse aortic constriction (TAC). The susceptibility to ventricular tachycardia (VT) assessed in an in vivo electrophysiological study was compared in the two genotypes. The effect of acute pharmacological blockade of AT1R on the incidences of arrhythmias was also assessed. As described previously, WT and AT1aR-KO mice with TAC developed cardiac hypertrophy to the same degree, but the incidence of VT was much lower in the latter. Moreover, although TAC induced an increase in tyrosine phosphorylation of connexin 43, a critical component of gap junctional channels, and a reduction in ventricular levels of connexin 43 protein in both genotypes, the effect was significantly ameliorated in AT1aR-KO mice. Acute pharmacological blockade of AT1R also reduced the incidence of arrhythmias. Our findings demonstrate that AT1aR-mediated signalling makes a direct contribution to the increase in arrhythmogenicity in hypertrophied hearts independently of structural remodelling. © 2013 The British Pharmacological Society.
Brown, Alexander J M; Lang, Chim; McCrimmon, Rory; Struthers, Allan
2017-08-23
Patients with diabetes have a two to fourfold increased risk for development of and death from cardiovascular disease [CVD]. The current oral hypoglycaemic agents result in limited reduction in this cardiovascular risk. Sodium glucose linked co-transporter type 2 [SGLT2] inhibitors are a relatively new class of antidiabetic agent that have been shown to have potential cardiovascular benefits. In support of this, the EMPA-REG trial showed a striking 38% and 35% reduction in cardiovascular mortality and heart failure [HF] hospitalisation respectively. The exact mechanism (s) responsible for these effects remain (s) unclear. One potential mechanism is regression of Left ventricular hypertrophy (LVH). The DAPA-LVH trial is a prospective, double-blind, randomised, placebo-controlled 'proof of concept' single-centre study that has been ongoing since January 2017. It is designed specifically to assess whether the SGLT2 inhibitor dapagliflozin regresses left ventricular [LV] mass in patients with diabetes and left ventricular hypertrophy [LVH]. We are utilising cardiac and abdominal magnetic resonance imaging [MRI] and ambulatory blood pressure monitoring to quantify the cardiovascular and systemic effects of dapagliflozin 10 mg once daily against standard care over a 1 year observation period. The primary endpoint is to detect the changes in LV mass. The secondary outcomes are to assess the changes in, LV volumes, blood pressure, weight, visceral and subcutaneous fat. This trial will be able to determine if SGLT2 inhibitor therapy reduces LV mass in patient with diabetes and LVH thereby strengthening their position as oral hypoglycaemic agents with cardioprotective benefits. Clinical Trials.gov: NCT02956811 . Registered November 2016.
Babua, Christopher; Kalyesubula, Robert; Okello, Emmy; Kakande, Barbara; Sebatta, Erias; Mungoma, Michael; Mondo, Charles
2015-08-04
Chronic kidney disease is a risk factor for development of cardiovascular diseases. Cardiovascular diseases are the primary cause of morbidity and mortality in patients with chronic kidney disease. There is limited data on cardiovascular diseases among chronic kidney disease patients in resource limited settings including Uganda. We determined the prevalence and patterns of cardiac diseases among patients with chronic kidney disease attending the nephrology outpatient clinic in Mulago National Referral Hospital in Uganda. This was a cross sectional study in which two hundred seventeen patients with chronic kidney disease were recruited over a period of 9 months. Data on demographic characteristics and risk factors for cardiovascular diseases were collected using a standardized questionnaire. Cardiac evaluation was done using resting electrocardiography and transthoracic echocardiography performed for all study participants and findings entered into a data sheet. One hundred eleven (51.2 %) of the 217 participants were male. Mean age was 42.8 years. One hundred eighteen (54.4 %) of patients had either eccentric or concentric left ventricular hypertrophy. Patients with left ventricular hypertrophy were more likely to be hypertensive (p < 0.001) or anemic (p = 0.034). Up to 9.2 % of study subjects had valvular heart disease (rheumatic or degenerative) and 22 % had pericarditis. Forty one patients (18.9 %) had left ventricular systolic failure (Ejection fraction < 50 %). There was a higher prevalence of systolic failure in patients with left ventricular hypertrophy (21 % vs. 16 %) although this was not statistically significant, p = 0.346. Thirty eight participants (17.5 %) had diastolic failure while 2 % had cardiac rhythm abnormalities. Cardiac abnormalities are common in a predominantly young African population with CKD. Clinicians should routinely screen and manage cardiovascular disease in CKD patients.
Toib, Amir; Zhang, Chen; Borghetti, Giulia; Zhang, Xiaoxiao; Wallner, Markus; Yang, Yijun; Troupes, Constantine D; Kubo, Hajime; Sharp, Thomas E; Feldsott, Eric; Berretta, Remus M; Zalavadia, Neil; Trappanese, Danielle M; Harper, Shavonn; Gross, Polina; Chen, Xiongwen; Mohsin, Sadia; Houser, Steven R
2017-09-01
Hypertrophic cardiomyopathy (HCM) is one of the most common genetic cardiac diseases and among the leading causes of sudden cardiac death (SCD) in the young. The cellular mechanisms leading to SCD in HCM are not well known. Prolongation of the action potential (AP) duration (APD) is a common feature predisposing hypertrophied hearts to SCD. Previous studies have explored the roles of inward Na + and Ca 2+ in the development of HCM, but the role of repolarizing K + currents has not been defined. The objective of this study was to characterize the arrhythmogenic phenotype and cellular electrophysiological properties of mice with HCM, induced by myosin-binding protein C (MyBPC) knockout (KO), and to test the hypothesis that remodeling of repolarizing K + currents causes APD prolongation in MyBPC KO myocytes. We demonstrated that MyBPC KO mice developed severe hypertrophy and cardiac dysfunction compared with wild-type (WT) control mice. Telemetric electrocardiographic recordings of awake mice revealed prolongation of the corrected QT interval in the KO compared with WT control mice, with overt ventricular arrhythmias. Whole cell current- and voltage-clamp experiments comparing KO with WT mice demonstrated ventricular myocyte hypertrophy, AP prolongation, and decreased repolarizing K + currents. Quantitative RT-PCR analysis revealed decreased mRNA levels of several key K + channel subunits. In conclusion, decrease in repolarizing K + currents in MyBPC KO ventricular myocytes contributes to AP and corrected QT interval prolongation and could account for the arrhythmia susceptibility. NEW & NOTEWORTHY Ventricular myocytes isolated from the myosin-binding protein C knockout hypertrophic cardiomyopathy mouse model demonstrate decreased repolarizing K + currents and action potential and QT interval prolongation, linking cellular repolarization abnormalities with arrhythmia susceptibility and the risk for sudden cardiac death in hypertrophic cardiomyopathy. Copyright © 2017 the American Physiological Society.
Borges, V T M; Zanati, S G; Peraçoli, M T S; Poiati, J R; Romão-Veiga, M; Peraçoli, J C; Thilaganathan, B
2018-04-01
Pre-eclampsia (PE) is associated with maternal cardiac remodeling and diastolic dysfunction. The aim of this study was to assess and compare maternal left ventricular structure and diastolic function and levels of brain natriuretic peptide (BNP) in women with early-onset (< 34 weeks' gestation) vs those with late-onset (≥ 34 weeks' gestation) PE. This was a prospective, cross-sectional, observational study of 30 women with early-onset PE, 32 with late-onset PE and 23 normotensive controls. Maternal cardiac structure and diastolic function were assessed by echocardiography and plasma levels of BNP were measured by enzyme immunoassay. Early- and late-onset PE were associated with increased left ventricular mass index and relative wall thickness compared with normotensive controls. In women with early-onset PE, the prevalence of concentric hypertrophy (40%) and diastolic dysfunction (23%) was also significantly higher (both P < 0.05) compared with women with late-onset PE (16% for both). Maternal serum BNP levels were significantly higher (P < 0.05) in women with early-onset PE and correlated with relative wall thickness and left ventricular mass index. Early-onset PE is associated with more severe cardiac impairment than is late-onset PE, as evidenced by an increased prevalence of concentric hypertrophy, diastolic dysfunction and higher levels of BNP. These findings suggest that early-onset PE causes greater myocardial damage, increasing the risk of both peripartum and postpartum cardiovascular morbidity. Although these cardiovascular effects are easily identified by echocardiographic parameters and measuring BNP, further studies are needed to assess their clinical utility. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
... or in combination with other medications to treat high blood pressure. Losartan is also used to decrease the risk of stroke in people who have high blood pressure and a heart condition called left ventricular hypertrophy ( ...
Elnakish, Mohammad T.; Ahmed, Amany A. E.; Mohler, Peter J.; Janssen, Paul M. L.
2015-01-01
Cardiac hypertrophy is the most documented cardiomyopathy following hyperthyroidism in experimental animals. Thyroid hormone-induced cardiac hypertrophy is described as a relative ventricular hypertrophy that encompasses the whole heart and is linked with contractile abnormalities in both right and left ventricles. The increase in oxidative stress that takes place in experimental hyperthyroidism proposes that reactive oxygen species are key players in the cardiomyopathy frequently reported in this endocrine disorder. The goal of this review is to shed light on the effects of thyroid hormones on the development of oxidative stress in the heart along with the subsequent cellular and molecular changes. In particular, we will review the role of thyroid hormone-induced oxidative stress in the development of cardiomyocyte hypertrophy and associated cardiac dysfunction, as well as the potential effectiveness of antioxidant treatments in attenuating these hyperthyroidism-induced abnormalities in experimental animal models. PMID:26146529
Isolated papillary muscle hypertrophy: A gap in our knowledge of hypertrophic cardiomyopathy?
Ferreira, Catarina; Delgado, Carlos; Vázquez, María; Trinidad, Carmen; Vilar, Manuel
2014-06-01
Increased thickness of left ventricular walls is the predominant characteristic and one of the diagnostic criteria of hypertrophic cardiomyopathy (HCM). This case illustrates an uncommon but important finding of isolated hypertrophy of the papillary muscles (PMs), observed in a young woman in whom an abnormal electrocardiogram was initially detected. During the investigation isolated PM hypertrophy was identified. The structural characteristics of the PMs have received scant attention in this setting and there is little information in the literature on this entity, whose real prevalence and clinical significance remain to be determined. The available information relates solitary PM hypertrophy with an early form or a different pattern of HCM. In this case PM hypertrophy was only detected due to the finding of an abnormal electrocardiogram, which prompted further diagnostic tests and a search for possible etiologies. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.
Valvular dysplasia and congestive heart failure in a juvenile African penguin (Spheniscus demersus).
McNaughton, Allyson; Frasca, Salvatore; Mishra, Neha; Tuttle, Allison D
2014-12-01
Abstract: An aquarium-housed, 6-mo-old African penguin (Spheniscus demersus) presented with acute respiratory distress. Auscultation revealed a grade II-III systolic murmur in the absence of adventitial sounds, and an enlarged heart without pulmonary edema was seen radiographically. Echocardiographic evaluation revealed atrioventricular (AV) valvular dysplasia and ventricular enlargement. The penguin was treated with enalapril, furosemide, and pimobendan but died within 3 wk of detection of the murmur. Congenital dysplasia of the right AV valve with right atrial and ventricular dilation and ventricular hypertrophy were diagnosed on postmortem examination.
Todica, Andrei; Beetz, Nick L; Günther, Lisa; Zacherl, Mathias J; Grabmaier, Ulrich; Huber, Bruno; Bartenstein, Peter; Brunner, Stefan; Lehner, Sebastian
2018-04-01
This study aims to analyze the left ventricular function parameters, scar load, and hypertrophy in a mouse model of pressure-overload left ventricular (LV) hypertrophy over the course of 8 weeks using 2-deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG) micro-positron emission tomography (microPET) imaging. LV hypertrophy was induced in C57BL/6 mice by transverse aortic constriction (TAC). Myocardial hypertrophy developed after 2-4 weeks. ECG-gated microPET scans with [ 18 F]FDG were performed 4 and 8 weeks after surgery. The extent of fibrosis was measured by histopathologic analysis. LV function parameters and scar load were calculated using QGS®/QPS®. LV metabolic volume (LVMV) and percentage injected dose per gram were estimated by threshold-based analysis. The fibrotic tissue volume increased significantly from 4 to 8 weeks after TAC (1.67 vs. 3.91 mm 3 ; P = 0.044). There was a significant increase of the EDV (4 weeks: 54 ± 15 μl, 8 weeks: 79 ± 32 μl, P < 0.01) and LVMV (4 weeks: 222 ± 24 μl, 8 weeks: 276 ± 52 μl, P < 0.01) as well as a significant decrease of the LVEF (4 weeks: 56 ± 17 %, 8 weeks: 44 ± 20 %, P < 0.01). The increase of LVMV had a high predictive value regarding the amount of ex vivo measured fibrotic tissue (R = 0.905, P < 0.001). The myocardial metabolic defects increased within 4 weeks (P = 0.055) but only moderately correlated with the fibrosis volume (R = 0.502, P = 0.021). The increase in end-diastolic volume showed a positive correlation with the fibrosis at 8 weeks (R = 0.763, P = 0.017). [ 18 F]FDG-PET is applicable for serial in vivo monitoring of the TAC mouse model. Myocardial hypertrophy, the dilation of the left ventricle, and the decrease in LVEF could be reliably quantified over time, as well as the developing localized scar. The increase in volume over time is predictive of a high fibrosis load.
Ayaz, Teslime; Kocaman, Sinan Altan; Durakoğlugil, Tuğba; Erdoğan, Turan; Şahin, Osman Zikrullah; Şahin, Serap Baydur; Çiçek, Yüksel; Şatiroğlu, Ömer
2014-01-01
Background and Objectives Left ventricular hypertrophy (LVH), a sign of subclinical cardiovascular disease, is an important predictor of cardiovascular morbidity and mortality. The aim of our study was to determine the association of left ventricular mass (LVM) with possible causative anthropometric and biochemical parameters as well as carotid intima-media thickness (CIMT) and brachial flow-mediated dilation (FMD) as surrogates of atherosclerosis and endothelial dysfunction, respectively, in previously untreated hypertensive patients. Subjects and Methods Our study included 114 consecutive previously untreated hypertensive patients who underwent echocardiography and ultrasonography to evaluate their vascular status and function via brachial artery CIMT and FMD. Results Among all study parameters, age, systolic blood pressure (BP), diastolic BP, pulse pressure, plasma glucose, uric acid, total bilirubin, direct bilirubin, hemoglobin, and CIMT were positively correlated with the LVM index. Multiple logistic regression analysis revealed that office systolic BP, age, male gender, and total bilirubin were independent predictors of LVH. Conclusion Bilirubin seems to be related to LVM and LVH. The positive association of bilirubin with these parameters is novel and requires further research. PMID:25278987
Cardiovascular studies in the mucopolysaccharidoses.
Nelson, J; Shields, M D; Mulholland, H C
1990-01-01
Cardiovascular studies were performed on 22 patients with mucopolysaccharidosis ascertained from an epidemiological study on the mucopolysaccharidoses in Northern Ireland. None of the patients had attended a cardiologist before the study. The main echocardiographical findings were thickening of the interventricular septum and left ventricular posterior wall in the absence of ECG evidence of ventricular hypertrophy. Moreover, reduced QRS voltages were present in the majority of the patients (77%) and some had reduced shortening fraction (33%). These findings suggest an infiltrative cardiomyopathy owing to mucopolysaccharide deposition as a cause of the cardiac thickening rather than true ventricular hypertrophy. Thickening of the mitral valve was present in one case and thickening of the aortic valve in two cases. Involvement of the other heart valves was minimal and aortic valve disease was not found in any of the cases of Morquio's disease type A. In conclusion, the clinical, ECG, and chest x ray findings and echocardiographical evidence for valvular involvement were significantly less than in other studies. Hence, the incidence of clinically significant cardiovascular disease in patients with mucopolysaccharidosis has probably been overestimated. PMID:2108248
Yu, Teng-Hung; Tang, Wei-Hua; Lu, Yung-Chuan; Wang, Chao-Ping; Hung, Wei-Chin; Wu, Cheng-Ching; Tsai, I-Ting; Chung, Fu-Mei; Houng, Jer-Yiing; Lan, Wen-Chun; Lee, Yau-Jiunn
2018-05-22
Left ventricular hypertrophy (LVH) is one of the most common cardiac abnormalities in patients with end-stage renal disease. Hippuric acid (HA), a harmful uremic toxin, is known to be elevated in patients with uremia, and serum HA levels are associated with neurological symptoms, metabolic acidosis, and accelerated renal damage associated with chronic kidney disease. However, the pathophysiological role of HA in patients with uremia remains unclear. We investigated the association between serum HA levels and echocardiographic measurements in patients undergoing hemodialysis (HD) treatment. Eighty consecutive patients treated at a single HD center (44 males, 36 females; mean age 66 y, mean HD duration 6 y) were included in this study. Comprehensive echocardiography was performed after HD. Blood samples were obtained before HD. Pearson's correlation analysis revealed that serum HA levels were positively correlated with diastolic blood pressure, serum creatinine, left ventricular mass index, end diastolic interventricular septal thickness, left ventricular end-diastolic diameter, left ventricular end systolic diameter, end systolic left ventricular posterior wall thickness, and left atrium diameter, and negatively correlated with age. Furthermore, the HD patients with LVH had higher median serum HA levels than those without LVH (34.2 vs. 18.1 μg/ml, p = 0.003). Multiple logistic regression analysis revealed that HA was independently associated with LVH even after adjusting for known biomarkers. Moreover, the receiver operator characteristics curve of HA showed that a HA level of >26.9 μg/ml was associated with LVH. HA was significantly associated with LVH. HA could be a novel biomarker of left ventricular overload, which is closely associated with an increased risk of death in HD patients. Copyright © 2018 Elsevier B.V. All rights reserved.
Cao, Jia-Li; Yang, Yu-Qing; Nabeel, Dookhun Muhammad; Sun, Ya-Li; Zou, Hua-Yi-Yang; Kong, Xiang-Qing; Lu, Xin-Zheng
The aim of this study is to investigate the correlation between calcineurin (CaN) and hypertension with left ventricular hypertrophy (HLVH) and to evaluate its potential clinical significance. The study involved 160 patients diagnosed with hypertension and 42 controls. Based on the exclusion criteria, 42 were not eligible for this study. The remaining 118 hypertensive patients were categorized into 2 subgroups based on left ventricular mass index and relative ventricular wall thickness: a normal model subgroup with hypertension (HNM) and an HLVH subgroup. Serum CaN levels were determined by enzyme-linked immunosorbent assay, while serum CaN activity was determined by malachite green colorimetric assay. Among the HNM and HLVH subgroups, a positive correlation was demonstrated between serum CaN activity, but not serum CaN level, and HLVH. Moreover, the HLVH subgroup displayed a remarkable increase in the levels of brain natriuretic peptide, cystatin C, urinary albumin/creatinine ratio, and left atrium diameter compared to the HNM subgroup and controls. There was a positive correlation between serum CaN activity and LVH in hypertensive patients. Activated CaN could play an important role in the pathophysiologic mechanism of HLVH. Serum CaN activity could be a clinically useful diagnostic and prognostic biomarker for LVH. © 2018 S. Karger AG, Basel.
Left ventricular structural and functional characteristics in Cushing's syndrome.
Muiesan, Maria Lorenza; Lupia, Mario; Salvetti, Massimo; Grigoletto, Consuelo; Sonino, Nicoletta; Boscaro, Marco; Rosei, Enrico Agabiti; Mantero, Franco; Fallo, Francesco
2003-06-18
This study was designed to evaluate left ventricular (LV) anatomy and function in patients with Cushing's syndrome. A high prevalence of LV hypertrophy and concentric remodeling has been reported in Cushing's syndrome, although no data have been reported on LV systolic and diastolic function. Forty-two consecutive patients with Cushing's syndrome and 42 control subjects, matched for age, gender, and blood pressure, were studied. Left ventricular mass index (LVMI) and relative wall thickness (RWT) were measured by echocardiography, endocardial and midwall fractional shortening (FS) were assessed, and diastolic filling was measured by Doppler transmitral flow. The RWT was significantly greater in Cushing patients than in controls. Left ventricular hypertrophy and concentric remodeling were observed in 10 and 26 patients with Cushing's syndrome, respectively. In Cushing patients, midwall FS was significantly reduced compared with controls (16.2 +/- 3% vs. 21 +/- 4.5%, p = 0.01). The ratio of transmitral E and A flow velocities was reduced and E deceleration time was prolonged in Cushing patients compared with controls (p = 0.03 and p < 0.001, respectively). In patients with Cushing's syndrome, cardiac structural changes are associated with reduced midwall systolic performance and with diastolic dysfunction that may contribute to the high risk of cardiovascular events observed in these patients.
Borlepawar, Ankush; Bernt, Alexander; Christen, Lynn; Sossalla, Samuel; Frank, Derk; Frey, Norbert
2017-01-01
We have previously shown that dysbindin is a potent inducer of cardiomyocyte hypertrophy via activation of Rho-dependent serum-response factor (SRF) signaling. We have now performed a yeast two-hybrid screen using dysbindin as bait against a cardiac cDNA library to identify the cardiac dysbindin interactome. Among several putative binding proteins, we identified tripartite motif-containing protein 24 (TRIM24) and confirmed this interaction by co-immunoprecipitation and co-immunostaining. Another tripartite motif (TRIM) family protein, TRIM32, has been reported earlier as an E3 ubiquitin ligase for dysbindin in skeletal muscle. Consistently, we found that TRIM32 also degraded dysbindin in neonatal rat ventricular cardiomyocytes as well. Surprisingly, however, TRIM24 did not promote dysbindin decay but rather protected dysbindin against degradation by TRIM32. Correspondingly, TRIM32 attenuated the activation of SRF signaling and hypertrophy due to dysbindin, whereas TRIM24 promoted these effects in neonatal rat ventricular cardiomyocytes. This study also implies that TRIM32 is a key regulator of cell viability and apoptosis in cardiomyocytes via simultaneous activation of p53 and caspase-3/-7 and inhibition of X-linked inhibitor of apoptosis. In conclusion, we provide here a novel mechanism of post-translational regulation of dysbindin and hypertrophy via TRIM24 and TRIM32 and show the importance of TRIM32 in cardiomyocyte apoptosis in vitro. PMID:28465353
Timing and Targeting of Treatment in Left Ventricular Hypertrophy.
Nam, Deokhwa; Reineke, Erin L
2017-01-01
In most clinical cases, left ventricular hypertrophy (LVH) occurs over time from persistent cardiac stress. At the molecular level, this results in both transient and long-term changes to metabolic, sarcomeric, ion handling, and stress signaling pathways. Although this is initially an adaptive change, the mechanisms underlying LVH eventually lead to maladaptive changes including fibrosis, decreased cardiac function, and failure. Understanding the regulators of long-term changes, which are largely driven by transcriptional remodeling, is a crucial step in identifying novel therapeutic targets for preventing the downstream negative effects of LVH and treatments that could reverse or prevent it. The development of effective therapeutics, however, will require a critical understanding of what to target, how to modify important pathways, and how to identify the stage of pathology in which a specific treatment should be used.
Acromegaly-induced cardiomyopathy with dobutamine-induced outflow tract obstruction.
Abdelsalam, Mahmoud A; Nippoldt, Todd B; Geske, Jeffrey B
2016-03-09
A 50-year-old man with a history of acromegaly was referred for preoperative cardiac evaluation preceding trans-sphenoidal resection of a pituitary macroadenoma. Dobutamine stress echocardiography was negative for myocardial ischaemia. Resting left ventricular (LV) LV ejection fraction (LVEF) was 64% and there was hypertrophy of ventricular septum (18 mm) without resting LV outflow tract obstruction. With 40 µg/kg/min of dobutamine, the LVEF became hyperdynamic at 80%, and there was a maximal instantaneous LV outflow tract gradient of 77 mm Hg. There was no delayed myocardial enhancement on cardiac MRI and the pattern of hypertrophy was concentric. Acromegaly-induced cardiomyopathy can mimic hypertrophic cardiomyopathy in the setting of dobutamine provocation. Because cardiomyopathy is an important cause of mortality in acromegaly, diagnosis and appropriate management are critical to improve survival. 2016 BMJ Publishing Group Ltd.
Matrix modulation and heart failure: new concepts question old beliefs.
Deschamps, Anne M; Spinale, Francis G
2005-05-01
Myocardial remodeling is a complex process involving several molecular and cellular factors. Extracellular matrix has been implicated in the remodeling process. Historically, the myocardial extracellular matrix was thought to serve solely as a means to align cells and provide structure to the tissue. Although this is one of its important functions, evidence suggests that the extracellular matrix plays a complex and divergent role in influencing cell behavior. This paper characterizes some of the notable studies on this dynamic entity and on adverse myocardial remodeling that have been published over the past year, which further question the belief that the extracellular matrix is a static structure. Progress has been made in understanding how the extracellular matrix is operative in the three major conditions (myocardial infarction, left ventricular hypertrophy due to overload, and dilated cardiomyopathy) that involve myocardial remodeling. Several studies have examined plasma profiles of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases following myocardial infarction and during left ventricular hypertrophy as surrogate markers of remodeling/remodeled myocardium. It has been demonstrated that bioactive signaling molecules and growth factors, proteases, and structural proteins influence cell-matrix interactions in the context of left ventricular hypertrophy. Finally, studies that either removed or added tissue inhibitor of metalloproteinases species in the myocardium demonstrated the importance of this regulatory protein in the remodeling process. Understanding the cellular and molecular triggers that in turn give rise to changes in the extracellular matrix could provide opportunities to modify the remodeling process.
Larstorp, Anne Cecilie K; Ariansen, Inger; Gjesdal, Knut; Olsen, Michael H; Ibsen, Hans; Devereux, Richard B; Okin, Peter M; Dahlöf, Björn; Kjeldsen, Sverre E; Wachtell, Kristian
2012-08-01
Previous studies have found pulse pressure (PP), a marker of arterial stiffness, to be an independent predictor of atrial fibrillation (AF) in general and hypertensive populations. We examined whether PP predicted new-onset AF in comparison with other blood pressure components in the Losartan Intervention For Endpoint reduction in hypertension study, a double-blind, randomized (losartan versus atenolol), parallel-group study, including 9193 patients with hypertension and electrocardiographic left ventricular hypertrophy. In 8810 patients with neither a history of AF nor AF at baseline, Minnesota coding of electrocardiograms confirmed new-onset AF in 353 patients (4.0%) during mean 4.9 years of follow-up. In multivariate Cox regression analyses, baseline and in-treatment PP and baseline and in-treatment systolic blood pressure predicted new-onset AF, independent of baseline age, height, weight, and Framingham Risk Score; sex, race, and treatment allocation; and in-treatment heart rate and Cornell product. PP was the strongest single blood pressure predictor of new-onset AF determined by the decrease in the -2 Log likelihood statistic, in comparison with systolic blood pressure, diastolic blood pressure, and mean arterial pressure. When evaluated in the same model, the predictive effect of systolic and diastolic blood pressures together was similar to that of PP. In this population of patients with hypertension and left ventricular hypertrophy, PP was the strongest single blood pressure predictor of new-onset AF, independent of other risk factors.
Leigh, J. Adam; O’Neal, Wesley T.; Soliman, Elsayed Z.
2016-01-01
Left ventricular hypertrophy (LVH) diagnosed by electrocardiography (ECG-LVH) and echocardiography (echo-LVH) are independently associated with an increased risk of cardiovascular disease (CVD) events. However, it is unknown if ECG-LVH retains its predictive properties independent of left ventricular anatomy. We compared the risk of CVD associated with ECG-LVH and echo-LVH in 4,076 participants (41% male, 86% white) from the Cardiovascular Health Study (CHS), who were free of baseline CVD. ECG-LVH was defined with Minnesota ECG Classification criteria from baseline ECG data. Echo-LVH was defined by sex-specific left ventricular mass values normalized to body surface area (male: >102 g/m2; female: >88 g/m2). ECG-LVH was detected in 144 (3.5%) participants and echo-LVH in 430 (11%) participants. Over a median follow-up of 10.6 years, 2,274 CVD events occurred. In a multivariable Cox regression analysis adjusted for common CVD risk factors, ECG-LVH (HR=1.84, 95%CI=1.51, 2.24) and echo-LVH (HR=1.35, 95%CI=1.19, 1.54) were associated with an increased risk for CVD events. The association between ECG-LVH and CVD events was not substantively altered with further adjustment for echo-LVH (HR=1.76, 95%CI=1.45, 2.15). In conclusion, the association of ECG-LVH with CVD events is not dependent on echo-LVH. This finding provides support to the concept that ECG-LVH is an electrophysiologic marker with predictive properties independent of left ventricular anatomy. PMID:27067620
Garciarena, Carolina D; Pinilla, Oscar A; Nolly, Mariela B; Laguens, Ruben P; Escudero, Eduardo M; Cingolani, Horacio E; Ennis, Irene L
2009-04-01
The effect of endurance training (swimming 90 min/d for 5 days a week for 60 days) on cardiac hypertrophy was investigated in the spontaneously hypertensive rat (SHR). Sedentary SHRs (SHR-Cs) and normotensive Wistar rats were used as controls. Exercise training enhanced myocardial hypertrophy assessed by left ventricular weight/tibial length (228+/-7 versus 251+/-5 mg/cm in SHR-Cs and exercised SHRs [SHR-Es], respectively). Myocyte cross-sectional area increased approximately 40%, collagen volume fraction decreased approximately 50%, and capillary density increased approximately 45% in SHR-Es compared with SHR-Cs. The mRNA abundance of atrial natriuretic factor and myosin light chain 2 was decreased by the swimming routine (100+/-19% versus 41+/-10% and 100+/-8% versus 61+/-9% for atrial natriuretic factor and myosin light chain 2 in SHR-Cs and SHR-Es, respectively). The expression of sarcoplasmic reticulum Ca(2+) pump was significantly augmented, whereas that of Na(+)/Ca(2+) exchanger was unchanged (93+/-7% versus 167+/-8% and 158+/-13% versus 157+/-7%, sarcoplasmic reticulum Ca(2+) pump and Na(+)/Ca(2+) exchanger in SHR-Cs and SHR-Es, respectively; P<0.05). Endurance training inhibited apoptosis, as reflected by a decrease in caspase 3 activation and poly(ADP-ribose) polymerase-1 cleavage, and normalized calcineurin activity without inducing significant changes in the phosphatidylinositol 3-kinase/Akt pathway. The swimming routine improved midventricular shortening determined by echocardiography (32.4+/-0.9% versus 36.9+/-1.1% in SHR-Cs and SHR-Es, respectively; P<0.05) and decreased the left ventricular free wall thickness/left ventricular cavity radius toward an eccentric model of cardiac hypertrophy (0.59+/-0.02 versus 0.53+/-0.01 in SHR-Cs and SHR-Es, respectively; P<0.05). In conclusion, we present data demonstrating the effectiveness of endurance training to convert pathological into physiological hypertrophy improving cardiac performance. The reduction of myocardial fibrosis and calcineurin activity plus the increase in capillary density represent factors to be considered in determining this beneficial effect.
Anabolic androgenic steroid-induced Takotsubo cardiomyopathy
Sella, Gianluigi; Bellanti, Giancarlo; Margheri, Massimo
2015-01-01
Anabolic steroid abuse, aimed at increasing muscle mass, has been growing in recent years. We describe a case of a 25-year-old bodybuilder who, after taking nandrolone and stanozolol, presented with Takotsubo syndrome. The angiography showed a normal coronary anatomy with the absence of stenosis. The left ventricular function was completely normalised after 1 week. PMID:25804946
When a Heart Murmur Signals Valve Disease
... in adults may be related to: Valve calcification Endocarditis Rheumatic fever In children, abnormal heart murmurs may ... Problem: Pulmonary Valve Regurgitation Heart Valves and Infective Endocarditis Left Ventricular Hypertrophy • Risks, Signs and Symptoms • Accurate ...
Left ventricular function in Friedreich's ataxia. An echocardiographic study.
Sutton, M G; Olukotun, A Y; Tajik, A J; Lovett, J L; Giuliani, E R
1980-01-01
Left ventricular function was assessed in seven patients with Friedreich's ataxia using computer-assisted analysis of the left ventricular echocardiograms and compared with those of 45 normal children matched for age and sex. The left ventricle in Friedreich's ataxia was symmetrically hypertrophied, cavity dimension was normal or small, and septal motion and peak velocity of circumferential shortening were normal in all patients. In diastole the duration of rapid filling was normal, peak rate of increase in left ventricular dimension was reduced in two patients, mitral valve opening was delayed with respect to minimum cavity dimension in seven, and there were significantly greater than normal increases in left ventricular dimension during the isovolumic period to mitral valve opening in seven, indicating abnormal and incoordinate relaxation. Peak rates of posterior wall systolic thickening and diastolic thinning were reduced in four and six patients, respectively, whereas peak rates of septal systolic thickening and diastolic thinning were reduced in one and four, respectively, suggesting a disproportionately greater impairment of the posterior wall than of septal function. The absence of asymmetric septal hypertrophy and mid-systolic closure of the aortic valve, the presence of normal septal motion, and the greater reduction in posterior wall than in septal dynamics are inconsistent with previous ideas that the heart disease of Friedreich's ataxia is identical to hypertrophic cardiomyopathy. Computer-assisted analysis of echocardiograms permits recognition of heart disease in Friedreich's ataxia before the onset of cardiac symptoms or development of clinical signs of heart disease. Images PMID:7426188
Borisov, Konstantin V
2017-07-01
Right ventricular (RV) hypertrophy is common in patients with hypertrophic cardiomyopathy (HCM), and is associated with more severe disease. Conventional surgical strategies such as the traditional Morrow procedure pose a particularly high risk to patients with severe hypertrophy and RV obstruction, for whom the most appropriate therapeutic approach has not yet been established. We have proposed a new technique for surgical correction in patients with hypertrophic obstructive cardiomyopathy and severe hypertrophy, which involves approaching the area of obstruction by entering through the conal part of the RV. This novel technique provides effective elimination of biventricular obstruction and the precise removal of the areas of septal fibrosis in patients with hypertrophic obstructive cardiomyopathy. The current literature review analyzes the indications and various techniques for performing a RV myectomy, and presents the results of follow-up assessments in patients with biventricular obstruction and severe hypertrophy.
Hypertension as a risk factor for heart failure.
Kannan, Arun; Janardhanan, Rajesh
2014-07-01
Hypertension remains a significant risk factor for development of congestive heart failure CHF), with various mechanisms contributing to both systolic and diastolic dysfunction. The pathogenesis of myocardial changes includes structural remodeling, left ventricular hypertrophy, and fibrosis. Activation of the sympathetic nervous system and renin-angiotensin system is a key contributing factor of hypertension, and thus interventions that antagonize these systems promote regression of hypertrophy and heart failure. Control of blood pressure is of paramount importance in improving the prognosis of patients with heart failure.
Pathological Left Ventricular Hypertrophy and Stem Cells: Current Evidence and New Perspectives.
Marketou, Maria E; Parthenakis, Fragiskos; Vardas, Panos E
2016-01-01
Left ventricular hypertrophy (LVH) is a strong predictor of adverse cardiovascular outcomes. It is the result of complex mechanisms that include not only an increase in protein synthesis and cell size but also proliferating cardiac progenitor cells and the influx of bone marrow-derived cells developing into cardiomyocytes. Stem and progenitor cells are known to contribute to the renewal of adult mammalian cardiomyocytes in case of myocardial injury or pressure and volume overload. They are activated in LVH and play a regulatory role in myocardial repair. They have high proliferative potential and secrete numerous cytokines, growth factors, and microRNAs that play important roles in cell differentiation, cardiac remodeling, and neovascularization. They are mobilized in response to either mechanical or chemical stimuli, hormones, or pharmacologic agents. Another important source of progenitor cells is the epicardial layer. It appears that precursor cells migrate from the epicardium to the myocardium in order to interact with myocardial cells. In addition, migratory cells participate in the formation of almost all cardiac structures in myocardial hypertrophy. Although the pathophysiological mechanisms are still obscure and further studies are required, their properties may open the door to regenerative cell therapy for the prevention of adverse remodeling.
Kontaraki, Joanna E; Marketou, Maria E; Kochiadakis, George E; Maragkoudakis, Spyros; Konstantinou, John; Vardas, Panos E; Parthenakis, Fragiskos I
2018-06-19
Long non-coding RNAs (lncRNAs) participate in the modulation of cardiac hypertrophy and they represent potential therapeutic targets in cardiovascular disease. We investigated the expression profiles of selected lncRNAs in peripheral blood mononuclear cells of patients with essential hypertension in relation to left ventricular hypertrophy. We assessed the expression levels of the lncRNAs MHRT, FENDRR and CARMEN using real-time reverse transcription polymerase chain reaction. Hypertensive patients showed significantly higher MHRT, FENDRR and CARMEN expression levels compared with healthy controls. In addition, we observed significant negative correlations of MHRT (r=-0.323, p=0.003) and FENDRR (r=-0.380, p=0.001) and a positive correlation of CARMEN (r=0.458, p<0.001) expression levels with left ventricular mass index. Our data reveal that the lncRNAs MHRT, FENDRR and CARMEN show distinct expression profiles in hypertensive patients and they possibly represent candidate therapeutic targets in hypertensive heart disease. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
2013-01-01
Background Strong associations have been observed between exposure to fine ambient particulate matter (PM2.5) and adverse cardiovascular outcomes. In particular, exposure to traffic related PM2.5 has been associated with increases in left ventricular hypertrophy, a strong risk factor for cardiovascular mortality. As much of traffic related PM2.5 is derived from diesel exhaust (DE), we investigated the effects of chronic DE exposure on cardiac hypertrophy and heart failure in the adult mouse by exposing mice to DE combined with either of two mouse models of cardiac hypertrophy: angiotensin II infusion or pressure overload induced by transverse aortic banding. Methods Wild type male C57BL/6 J mice were either infused with angiotensin II (800 ng/kg/min) via osmotic minipump implanted subcutaneously for 1 month, or underwent transverse aortic banding (27 gauge needle 1 week for observing acute reactions, 26 gauge needle 3 months or 6 months for observing chronic reactions). Vehicle (saline) infusion or sham surgery was used as a control. Shortly after surgery, mice were transferred to our exposure facility and randomly assigned to either diesel exhaust (300 or 400 μg/m3) or filtered air exposures. After reaching the end of designated time points, echocardiography was performed to measure heart structure and function. Gravimetric analysis was used to measure the ventricular weight to body weight ratio. We also measured heart rate by telemetry using implanted ambulatory ECG monitors. Results Both angiotensin II and transverse aortic banding promoted cardiac hypertrophy compared to vehicle or sham controls. Transverse aortic banding for six months also promoted heart failure in addition to cardiac hypertrophy. In all cases, DE failed to exacerbate the development of hypertrophy or heart failure when compared to filtered air controls. Prolonged DE exposure also led to a decrease in average heart rate. Conclusions Up to 6-months of DE exposure had no effect on cardiac hypertrophy and heart function induced by angiotensin II stimulation or pressure overload in adult C57BL/6 J mice. This study highlights the potential importance of particle constituents of ambient PM2.5 to elicit cardiotoxic effects. Further investigations on particle constituents and cardiotoxicity are warranted. PMID:24093778
Rajani, Ali Raza; Murugesan, Vagishwari; Baslaib, Fahad Omar; Rafiq, Muhammad Anwer
2014-01-01
A 27-year-old woman with a history of bileaflet mitral valve prolapse and moderate mitral regurgitation presented to our emergency with untractable polymorphic wide complex tachycardia and unstable haemodynamics. After cardiopulmonary resuscitation, return of spontaneous circulation was achieved 30 min later. Her post-resuscitation ECG showed a prolonged QT interval which progressively normalised over the same day. Her laboratory investigations revealed hypocalcaemia while other electrolytes were within normal limits. A diagnosis of ventricular arrhythmia secondary to structural heart disease further precipitated by hypocalcaemia was made. Further hospital stay did not reveal a recurrence of prolonged QT interval or other arrhythmias except for an episode of non-sustained ventricular tachycardia. However, the patient suffered diffuse hypoxic brain encephalopathy secondary to prolonged cardiopulmonary resuscitation. PMID:24827670
Ding, X; Xu, X; Yan, Y; Song, X; Liu, S; Wang, G; Su, D; Jing, Q; Qin, Y
2015-06-01
The aim of this study was to investigate whether renal sympathetic denervation (RSD) is more effective on myocardial hypertrophy than the angiotensin-converting enzyme inhibitor (ACEI) perindopril in spontaneously hypertensive rats (SHRs). After bilateral renal denervation blood pressure (BP) was measured every 10 days. On day 50 the heart was (histo)pathologically examined. The ventricular weight to body weight ratios (VW/BW), myocardial diameter and collagen volume fraction (CVF) were calculated, and cardiac hypertrophy marker genes were analyzed by RT-PCR. At the baseline evaluation all groups had comparable BP. After treatment the BP of the RSD group was significantly reduced (p < 0.05). The BP of the RSD group was lower than that of the perindopril group on days 10, 20 and 30th (p < 0.05) but on day 50 systolic BP of the RSD group was significantly higher (p < 0.05) whereas there were no significant differences in diastolic BP. The VW/BW decreased in the RSD group, whereas the value did not change significantly in the perindopril group. The myocardial diameter of the left ventricular cardiomyocytes was also significantly lower in the RSD group and stayed the same in the perindopril group. Collagen volume fraction (CVF) in the RSD group was significantly lower than in the perindopril group (p < 0.05). Significant changes in the expression levels of NPPA, MYH7, and MYH6 (P < 0.05) were observed in the RD-SHR groups (p < 0.05). There was a significant difference in the expression level of MYH6 (p < 0.05) between the RSD group and the perindopril group but the expression levels of NPPA and MYH7 were not significantly different. In this study, RSD had a significant antihypertensive effect and inhibited hypertensive-induced cardiac hypertrophy in SHRs and showed advantages compared with ACEI in decreasing BP in the early stage and in inhibiting myocardial fibrosis.
Pouleur, Anne-Catherine; Anker, Stefan; Brito, Dulce; Brosteanu, Oana; Hasenclever, Dirk; Casadei, Barbara; Edelmann, Frank; Filippatos, Gerasimos; Gruson, Damien; Ikonomidis, Ignatios; Lhommel, Renaud; Mahmod, Masliza; Neubauer, Stefan; Persu, Alexandre; Gerber, Bernhard L; Piechnik, Stefan; Pieske, Burkert; Pieske-Kraigher, Elisabeth; Pinto, Fausto; Ponikowski, Piotr; Senni, Michele; Trochu, Jean-Noël; Van Overstraeten, Nancy; Wachter, Rolf; Balligand, Jean-Luc
2018-06-22
Progressive left ventricular (LV) remodelling with cardiac myocyte hypertrophy, myocardial fibrosis, and endothelial dysfunction plays a key role in the onset and progression of heart failure with preserved ejection fraction. The Beta3-LVH trial will test the hypothesis that the β 3 adrenergic receptor agonist mirabegron will improve LV hypertrophy and diastolic function in patients with hypertensive structural heart disease at high risk for developing heart failure with preserved ejection fraction. Beta3-LVH is a randomized, placebo-controlled, double-blind, two-armed, multicentre, European, parallel group study. A total of 296 patients will be randomly assigned to receive either mirabegron 50 mg daily or placebo over 12 months. The main inclusion criterion is the presence of LV hypertrophy, that is, increased LV mass index (LVMi) or increased wall thickening by echocardiography. The co-primary endpoints are a change in LVMi by cardiac magnetic resonance imaging and a change in LV diastolic function (assessed by the E/e' ratio). Secondary endpoints include mirabegron's effects on cardiac fibrosis, left atrial volume index, maximal exercise capacity, and laboratory markers. Two substudies will evaluate mirabegron's effect on endothelial function by pulse amplitude tonometry and brown fat activity by positron emission tomography using 17F-fluorodeoxyglucose. Morbidity and mortality as well as safety aspects will also be assessed. Beta3-LVH is the first large-scale clinical trial to evaluate the effects of mirabegron on LVMi and diastolic function in patients with LVH. Beta3-LVH will provide important information about the clinical course of this condition and may have significant impact on treatment strategies and future trials in these patients. © 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.
Leibowitz, David; Planer, David; Ben-Ibgi, Fanny; Rott, David; Weiss, A Teddy; Bursztyn, Michael
2007-02-01
Clinical echocardiographic assessment of left ventricular hypertrophy (LVH) is generally performed by measuring wall thickness alone (WT). The objective of this study was to compare the assessment of LVH using the measurement of WT to that using indexed LV mass. Hypertensive patients underwent echocardiography with the measurement of LV WT and LV mass. For each patient, the presence of LVH was assessed by both methods with WT compared to the gold standard of LV mass index. In all, 92 patients (51M/41F) were entered, and in only 55 patients (60%) were the two methods concordant. There was a tendency for WT to underestimate LVH in females (sensitivity 37%, specificity 79%) and overestimate LVH in males (sensitivity 88%, specificity 56%). The measurement of WT alone overestimates LVH in males and underestimates LVH in females and should not be used as a surrogate marker for increased LV mass.
Boonpeng, Hoh; Yusoff, Khalid
2013-03-01
The ultimate goal of human genetics is to understand the role of genome variation in elucidating human traits and diseases. Besides single nucleotide polymorphism (SNP), copy number variation (CNV), defined as gains or losses of a DNA segment larger than 1 kb, has recently emerged as an important tool in understanding heritable source of human genomic differences. It has been shown to contribute to genetic susceptibility of various common and complex diseases. Despite a handful of publications, its role in cardiovascular diseases remains largely unknown. Here, we deliberate on the currently available technologies for CNV detection. The possible utility and the potential roles of CNV in exploring the mechanisms of cardiac remodeling in hypertension will also be addressed. Finally, we discuss the challenges for investigations of CNV in cardiovascular diseases and its possible implications in diagnosis of hypertension-related left ventricular hypertrophy (LVH).
Long, Webb E; Wilson, Allen D; Srinivasan, Shardha; Seeger, Kimberly J; Maginot, Kathleen R
2009-10-01
The etiology of isolated right ventricular hypertrophy (RVH) is distinct from other forms of hypertrophic cardiomyopathy. RVH is typically seen in the setting of pulmonary valve stenosis or Tetralogy of Fallot. A rare cause of isolated RVH is premature closure of the patent ductus arteriosus (PDA) in utero that results in pulmonary hypertension. This can have a range of outcomes, from spontaneous resolution to fetal demise. This case report describes a term infant who presented with respiratory distress and striking isolated RVH, pulmonary hypertension, and no PDA. She was treated conservatively with supplemental oxygen. The patient was gradually weaned off oxygen over the course of two weeks and follow-up echocardiography showed resolution of her RVH and pulmonary hypertension by 14 weeks of age. The presentation and course of this patient with severe isolated RVH is consistent with spontaneous premature closure of the ductus arteriosus in utero.
Cauley, Edmund; Wang, Xin; Dyavanapalli, Jhansi; Sun, Ke; Garrott, Kara; Kuzmiak-Glancy, Sarah; Kay, Matthew W; Mendelowitz, David
2015-10-01
Hypertension, cardiac hypertrophy, and heart failure (HF) are widespread and debilitating cardiovascular diseases that affect nearly 23 million people worldwide. A distinctive hallmark of these cardiovascular diseases is autonomic imbalance, with increased sympathetic activity and decreased parasympathetic vagal tone. Recent device-based approaches, such as implantable vagal stimulators that stimulate a multitude of visceral sensory and motor fibers in the vagus nerve, are being evaluated as new therapeutic approaches for these and other diseases. However, little is known about how parasympathetic activity to the heart is altered with these diseases, and this lack of knowledge is an obstacle in the goal of devising selective interventions that can target and selectively restore parasympathetic activity to the heart. To identify the changes that occur within the brain stem to diminish the parasympathetic cardiac activity, left ventricular hypertrophy was elicited in rats by aortic pressure overload using a transaortic constriction approach. Cardiac vagal neurons (CVNs) in the brain stem that generate parasympathetic activity to the heart were identified with a retrograde tracer and studied using patch-clamp electrophysiological recordings in vitro. Animals with left cardiac hypertrophy had diminished excitation of CVNs, which was mediated both by an augmented frequency of spontaneous inhibitory GABAergic neurotransmission (with no alteration of inhibitory glycinergic activity) as well as a diminished amplitude and frequency of excitatory neurotransmission to CVNs. Opportunities to alter these network pathways and neurotransmitter receptors provide future targets of intervention in the goal to restore parasympathetic activity and autonomic balance to the heart in cardiac hypertrophy and other cardiovascular diseases. Copyright © 2015 the American Physiological Society.
Brooks, Wesley W; Conrad, Chester H; Robinson, Kathleen G; Colucci, Wilson S; Bing, Oscar H L
2009-02-01
The effects of long-term oral administration of L-arginine, a substrate for nitric oxide (NO) production, on left ventricular (LV) remodeling, myocardial function and the prevention of heart failure (HF) was compared to the angiotensin-converting enzyme (ACE) inhibitor captopril in a rat model of hypertensive HF (aged spontaneously hypertensive rat (SHR)). SHRs and age-matched normotensive Wistar-Kyoto (WKY) rats were assigned to either no treatment, treatment with L-arginine (7.5 g/l in drinking water) or captopril (1 g/l in drinking water) beginning at 14 months of age, a time when SHRs exhibit stable compensated hypertrophy with no hemodynamic impairment; animals were studied at 23 months of age or at the time of HF. In untreated SHR, relative to WKY, there was significant LV hypertrophy, myocardial fibrosis, and isolated LV muscle performance and response to isoproterenol (ISO) were depressed; and, 7 of 10 SHRs developed HF. Captopril administration to six SHRs attenuated hypertrophy and prevented impaired inotropic responsiveness to ISO, contractile dysfunction, fibrosis, increased passive stiffness, and HF. In contrast, L-arginine administration to SHR increased LV hypertrophy and myocardial fibrosis while cardiac performance was depressed; and 7 of 9 SHRs developed HF. In WKY, L-arginine treatment but not captopril resulted in increased LV weight and the contractile response to ISO was blunted. Neither L-arginine nor captopril treatment of WKY changed fibrosis and HF did not occur. These data demonstrate that in contrast to captopril, long-term treatment with L-arginine exacerbates age-related cardiac hypertrophy, fibrosis, and did not prevent contractile dysfunction or the development of HF in aging SHR.
Peng, Long-yun; Ma, Hong; He, Jian-gui; Gao, Xiu-ren; Zhang, Yan; He, Xiao-hong; Zhai, Yuan-sheng; Zhang, Xue-jiao
2006-08-01
To explore the effects of ischemic postconditioning on ischemia/reperfusion injury in isolated hypertrophied rat heart and investigate the signal transduction pathway changes induced by ischemia postconditioning. Cardiac hypertrophy was induced in rats by abdominal aortic banding, and isolated hypertrophied rat heart ischemia/reperfusion model was made by Langendorff technique to evaluate the effects of ischemia postconditioning on left ventricular systole pressure, coronary artery flow, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) release, myocardial infarction size, and the level of myocardial phospho-protein kinase B/Akt (Ser473), phospho-glycogen synthase kinase-3beta (Ser9). Following groups were studied (n = 12 each group): IR, 30 min ischemia (I)/60 min Reperfusion (R); Post: 30 min ischemia, 6 circles of 10 s I/10 s R followed by 60 min R; Post Wort: 30 min ischemia, 6 circles of 10 s I/10 s R, wortmannin (10(-7) mol/L) followed by 60 min R; Wort: 30 min ischemia, wortmannin (10(-7) mol/L) followed by 60 min R. Left ventricular systolic pressure and coronary artery flow were significantly increased, myocardial infarction size and the release of CPK, LDH significantly reduced in Post group compared to that in IR group. Phospho-protein kinase B/Akt (Ser473) and phospho-glycogen synthase kinase-3beta (Ser9) levels were also significantly higher in Post group than that in IR group. Phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin prevented the increase of phospho-protein kinase B/Akt (Ser473) and phospho-glycogen synthase kinase-3beta (Ser9) induced by ischemic postconditioning, but only partly abolished the cardioprotection of ischemic postconditioning. Ischemic postconditioning attenuates ischemia/reperfusion injury in isolated hypertrophied rat heart. The cardioprotective effects of ischemic postconditioning were partly mediated through PI3K/Akt/GSK-3beta signaling pathway.
Kameny, Rebecca Johnson; He, Youping; Zhu, Terry; Gong, Wenhui; Raff, Gary W; Chapin, Cheryl J; Datar, Sanjeev A; Boehme, Jason; Hata, Akiko; Fineman, Jeffrey R
2018-06-15
The right ventricular (RV) response to pulmonary arterial hypertension (PAH) is heterogeneous. Most patients have maladaptive changes with RV dilation and failure while some-especially patients with PAH secondary to congenital heart disease (CHD)-have an adaptive response with hypertrophy and preserved systolic function. Mechanisms for RV adaptation to PAH are unknown despite RV function being a primary determinant of mortality. In our CHD ovine model with fetally-implanted aortopulmonary shunt (shunt lambs), we previously demonstrated an adaptive physiologic RV response to increased afterload with hypertrophy. In this study, we examined small noncoding microRNA (miRNA) expression in shunt RV and characterized downstream effects of a key miRNA. RV tissue was harvested from 4-week-old shunt and control lambs (n=5) and miRNA, mRNA, and proteins were quantitated. We found differential expression of 40 cardiovascular-specific miRNA in shunt RV. Interestingly, this miRNA signature is distinct from models of RV failure, suggesting that miRNAs might contribute to adaptive RV hypertrophy. Among RV miRNAs, miR-199b is decreased in RV with eventual downregulation of nuclear factor of activated T-cells (NFAT)/calcineurin signaling. Furthermore, anti-fibrotic miR-29a is increased in shunt RV with reduction of miR-29 targets Collagen A1 and 3A1 and decreased fibrosis. Thus, we conclude that the miRNA signature specific to shunt lambs is distinct from RV failure and drives gene expression required for adaptive RV hypertrophy. We propose that the adaptive RV miRNA signature may serve as a prognostic and therapeutic tool in patients with PAH to attenuate or prevent progression of RV failure and premature death.
Usefulness of Epicardial Area in the Short Axis to Identify Elevated Left Ventricular Mass in Men.
Fitzpatrick, Jesse K; Cohen, Beth E; Rosenblatt, Andrew; Shaw, Richard E; Schiller, Nelson B
2018-06-15
Left ventricular (LV) hypertrophy is strongly associated with increased cardiovascular morbidity and mortality. The 2-dimensional LV mass algorithms suffer from measurement variability that can lead to misclassification of patients with LV hypertrophy as normal, or vice versa. Among the 4 echocardiographic measurements required by the 2-dimensional LV mass algorithms, epicardial and endocardial area have the lowest interobserver variation and could be used to corroborate LV mass calculations. We sought cut-off values that are able to discriminate between elevated and normal LV mass based on endocardial or epicardial area alone. Using data from 664 men enrolled in the Mind Your Heart Study, we calculated the correlation of LV mass index with epicardial area and endocardial area. We then used receiver operator characteristic curves to identify epicardial and endocardial area cut-points that could discriminate subjects with normal LV mass and LV hypertrophy. LV mass index was more strongly correlated with epicardial area compared with endocardial area, r = 0.70 versus r = 0.27, respectively. Epicardial area had a significantly higher area under the receiver operator characteristic curve (p <0.001) compared with endocardial area, 0.90 (95% confidence interval 0.86 to 0.93) versus 0.63 (95% confidence interval 0.57 to 0.71). An epicardial area cut-point of ≥38.0 cm 2 corresponded to a sensitivity of 95.0% and specificity of 54.4% for detecting LV hypertrophy. In conclusion, epicardial area showed promise as a method of rapid screening for LV hypertrophy and could be used to validate formal LV mass calculations. Copyright © 2018 Elsevier Inc. All rights reserved.
Acetylation contributes to hypertrophy-caused maturational delay of cardiac energy metabolism.
Fukushima, Arata; Zhang, Liyan; Huqi, Alda; Lam, Victoria H; Rawat, Sonia; Altamimi, Tariq; Wagg, Cory S; Dhaliwal, Khushmol K; Hornberger, Lisa K; Kantor, Paul F; Rebeyka, Ivan M; Lopaschuk, Gary D
2018-05-17
A dramatic increase in cardiac fatty acid oxidation occurs following birth. However, cardiac hypertrophy secondary to congenital heart diseases (CHDs) delays this process, thereby decreasing cardiac energetic capacity and function. Cardiac lysine acetylation is involved in modulating fatty acid oxidation. We thus investigated what effect cardiac hypertrophy has on protein acetylation during maturation. Eighty-four right ventricular biopsies were collected from CHD patients and stratified according to age and the absence (n = 44) or presence of hypertrophy (n = 40). A maturational increase in protein acetylation was evident in nonhypertrophied hearts but not in hypertrophied hearts. The fatty acid β-oxidation enzymes, long-chain acyl CoA dehydrogenase (LCAD) and β-hydroxyacyl CoA dehydrogenase (βHAD), were hyperacetylated and their activities positively correlated with their acetylation after birth in nonhypertrophied hearts but not hypertrophied hearts. In line with this, decreased cardiac fatty acid oxidation and reduced acetylation of LCAD and βHAD occurred in newborn rabbits subjected to cardiac hypertrophy due to an aortocaval shunt. Silencing the mRNA of general control of amino acid synthesis 5-like protein 1 reduced acetylation of LCAD and βHAD as well as fatty acid oxidation rates in cardiomyocytes. Thus, hypertrophy in CHDs prevents the postnatal increase in myocardial acetylation, resulting in a delayed maturation of cardiac fatty acid oxidation.
Lottonen-Raikaslehto, Line; Rissanen, Riina; Gurzeler, Erika; Merentie, Mari; Huusko, Jenni; Schneider, Jurgen E; Liimatainen, Timo; Ylä-Herttuala, Seppo
2017-03-01
Cardiac-specific overexpression of vascular endothelial growth factor (VEGF)-B 167 is known to induce left ventricular hypertrophy due to altered lipid metabolism, in which ceramides accumulate to the heart and cause mitochondrial damage. The aim of this study was to evaluate and compare different imaging methods to find the most sensitive way to diagnose at early stage the progressive left ventricular remodeling leading to heart failure. Echocardiography and cardiovascular magnetic resonance imaging were compared for imaging the hearts of transgenic mice with cardiac-specific overexpression of VEGF-B 167 and wild-type mice from 5 to 14 months of age at several time points. Disease progression was verified by molecular biology methods and histology. We showed that left ventricular remodeling is already ongoing at the age of 5 months in transgenic mice leading to heart failure by the age of 14 months. Measurements from echocardiography and cardiovascular magnetic resonance imaging revealed similar changes in cardiac structure and function in the transgenic mice. Changes in histology, gene expressions, and electrocardiography supported the progression of left ventricular hypertrophy. Longitudinal relaxation time in rotating frame (T 1 ρ ) in cardiovascular magnetic resonance imaging could be suitable for detecting severe fibrosis in the heart. We conclude that cardiac-specific overexpression of VEGF-B 167 leads to left ventricular remodeling at early age and is a suitable model to study heart failure development with different imaging methods. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.
Markus, Marcello Ricardo Paulista; Stritzke, Jan; Lieb, Wolfgang; Mayer, Björn; Luchner, Andreas; Döring, Angela; Keil, Ulrich; Hense, Hans-Werner; Schunkert, Heribert
2008-10-01
It is unclear whether persistent prehypertension causes structural or functional alterations of the heart. We examined echocardiographic data of 1005 adults from a population-based survey at baseline in 1994/1995 and at follow-up in 2004/2005. We compared individuals who had either persistently normal (<120 mmHg systolic and <80 mmHg diastolic, n = 142) or prehypertensive blood pressure (120-139 mmHg or 80-89 mmHg, n = 119) at both examinations using multivariate regression modeling. Over 10 years, left ventricular end-diastolic diameters were stable and did not differ between the two groups. However, the prehypertensive blood pressure group displayed more pronounced ageing-related increases of left ventricular wall thickness (+4.7 versus +11.9%, P < 0.001) and left ventricular mass (+8.6 versus +15.7%, P = 0.006). Prehypertension was associated with a raised incidence of left ventricular concentric remodeling (adjusted odds ratio 10.7, 95% confidence interval 2.82-40.4) and left ventricular hypertrophy (adjusted odds ratio 5.33, 1.58-17.9). The ratio of early and late diastolic peak transmitral flow velocities (E/A) decreased by 7.7% in the normal blood pressure versus 15.7% in the prehypertensive blood pressure group (P = 0.003) and at follow-up the ratio of early diastolic peak transmitral flow and early diastolic peak myocardial relaxation velocities (E/EM) was higher (9.1 versus 8.5, P = 0.031) and left atrial size was larger (36.5 versus 35.3 mm, P = 0.024) in the prehypertensive blood pressure group. Finally, the adjusted odds ratio for incident diastolic dysfunction was 2.52 (1.01-6.31) for the prehypertensive blood pressure group. Persistent prehypertension accelerates the development of hypertrophy and diastolic dysfunction of the heart.
Double product and end-organ damage in African and Caucasian men: the SABPA study.
Schultz, A J; Schutte, A E; Schutte, R
2013-08-10
Increasing urbanisation in sub-Saharan African countries is causing a rapid increase in cardiovascular disease. Evidence suggests that Africans have higher blood pressures and a higher prevalence of hypertension-related cardiovascular morbidity and mortality, compared to Caucasians. We investigated double product (systolic blood pressure × heart rate), a substantial measure of cardiac workload, as a possible cardiovascular risk factor in African and Caucasian men. The study consisted of 101 urbanised African and 101 Caucasian male school teachers. We measured 24h ambulatory blood pressure and the carotid cross-sectional wall area, and determined left ventricular hypertrophy electrocardiographically by means of the Cornell product. Urinary albumin and creatinine were analysed to obtain the albumin-to-creatinine ratio. Africans had higher 24h, daytime and nighttime systolic- and diastolic blood pressure, heart rate and resultant double product compared to the Caucasians. In addition, markers of end-organ damage, albumin-to-creatinine ratio and left ventricular hypertrophy were higher in the Africans while cross-sectional wall area did not differ. In Africans after single partial and multiple regression analysis, 24h systolic blood pressure, but not double product or heart rate, correlated positively with markers of end-organ damage (cross-sectional wall area: β=0.398, P=0.005; left ventricular hypertrophy: β=0.455, P<0.001; albumin-to-creatinine ratio: β=0.280, P=0.012). No associations were evident in Caucasian men. Double product may not be a good marker of increased cardiovascular risk when compared to systolic blood pressure in African and Caucasian men. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Saifudeen, Ismael; Subhadra, Lakshmi; Konnottil, Remani; Nair, R Renuka
2017-03-01
Left ventricular hypertrophy (LVH) is characterized by a decrease in oxidation of long-chain fatty acids, possibly mediated by reduced expression of the cell-surface protein cluster of differentiation 36 (CD36). Spontaneously hypertensive rats (SHRs) were therefore supplemented with medium-chain triglycerides (MCT), a substrate that bypasses CD36, based on the assumption that the metabolic modulation will ameliorate ventricular remodeling. The diet of 2-month-old and 6-month-old SHRs was supplemented with 5% MCT (Tricaprylin), for 4 months. Metabolic modulation was assessed by mRNA expression of peroxisome proliferator-activated receptor α and medium-chain acyl-CoA dehydrogenase. Blood pressure was measured noninvasively. LVH was assessed with the use of hypertrophy index, cardiomyocyte cross-sectional area, mRNA expression of B-type natriuretic peptide, cardiac fibrosis, and calcineurin-A levels. Oxidative stress indicators (cardiac malondialdehyde, protein carbonyl, and 3-nitrotyrosine levels), myocardial energy level (ATP, phosphocreatine), and lipid profile were determined. Supplementation of MCT stimulated fatty acid oxidation in animals of both age groups, reduced hypertrophy and oxidative stress along with the maintenance of energy level. Blood pressure, body weight, and lipid profile were unaffected by the treatment. The results indicate that modulation of myocardial fatty acid metabolism by MCT prevents progressive cardiac remodeling in SHRs, possibly by maintenance of energy level and decrease in oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.
Papademetriou, V; Gottdiener, J S; Fletcher, R D; Freis, E D
1985-09-15
Systemic hypertension is a common cause of congestive heart failure. However, left ventricular (LV) systolic function remains normal for many years in patients with mild or moderate hypertension. In this study, high-quality M-mode echocardiograms were recorded in 7 patients with borderline hypertension, 14 patients with mild hypertension and 15 normal persons. Measures of systolic and diastolic LV function and the degree of LV hypertrophy were studied with the assistance of a tablet digitizer and dedicated microcomputer. Average blood pressure was 125 +/- 10/77 +/- 7 mm Hg in normal subjects, 146 +/- 18/92 +/- 2 mm Hg in patients with borderline hypertension and 150 +/- 11/102 +/- 4 in patients with mild hypertension. Indexes of systolic LV function were similar in all 3 groups. The peak rate of early relaxation of the LV posterior wall was significantly decreased in the group of patients with mild hypertension (4.7 vs 6.6 sec-1, p less than 0.01). The mitral valve closure rate was 150 +/- 32 mm/s in normal subjects, 119 +/- 35 mm/s in patients with borderline hypertension and 106 +/- 26 mm/s (p less than 0.001) in patients with mild hypertension. Mild LV hypertrophy was present in 6 of 7 patients with borderline and 13 of 14 patients with mild hypertension. The degree of hypertrophy and the level of blood pressure correlated poorly.(ABSTRACT TRUNCATED AT 250 WORDS)
Long-Term Effects of Spironolactone in Peritoneal Dialysis Patients
Mizuno, Masashi; Suzuki, Yasuhiro; Tamai, Hirofumi; Hiramatsu, Takeyuki; Ohashi, Hiroshige; Ito, Isao; Kasuga, Hirotake; Horie, Masanobu; Maruyama, Shoichi; Yuzawa, Yukio; Matsubara, Tatsuaki; Matsuo, Seiichi
2014-01-01
ESRD treated with dialysis is associated with increased left ventricular hypertrophy, which, in turn, is related to high mortality. Mineralocorticoid receptor antagonists improve survival in patients with chronic heart failure; however, the effects in patients undergoing dialysis remain uncertain. We conducted a multicenter, open-label, prospective, randomized trial with 158 patients receiving angiotensin-converting enzyme inhibitor or angiotensin type 1 receptor antagonist and undergoing peritoneal dialysis with and without (control group) spironolactone for 2 years. As a primary endpoint, rate of change in left ventricular mass index assessed by echocardiography improved significantly at 6 (P=0.03), 18 (P=0.004), and 24 (P=0.01) months in patients taking spironolactone compared with the control group. Rate of change in left ventricular ejection fraction improved significantly at 24 weeks with spironolactone compared with nontreatment (P=0.02). The benefits of spironolactone were clear in patients with reduced residual renal function. As secondary endpoints, renal Kt/V and dialysate-to-plasma creatinine ratio did not differ significantly between groups during the observation period. No serious adverse effects, such as hyperkalemia, occurred. In this trial, spironolactone prevented cardiac hypertrophy and decreases in left ventricular ejection fraction in patients undergoing peritoneal dialysis, without significant adverse effects. Further studies, including those to determine relative effectiveness in women and men and to evaluate additional secondary endpoints, should confirm these data in a larger cohort. PMID:24335969
Ghrelin and its promoter variant associated with cardiac hypertrophy.
Ukkola, O; Pääkkö, T; Kesäniemi, Y A
2012-07-01
The roles of ghrelin, a peptide hormone that has a role in regulating food intake and energy homeostasis, in the cardiovascular system have not yet been unambiguously established. We evaluated the association between plasma ghrelin concentrations and -501A>C single-nucleotide polymorphism (SNP) in the ghrelin gene 5' flanking area and echocardiographic measurements in 1037 middle-aged subjects. Left ventricular mass index (LVMI) was calculated according to Devereux's method. The ambulatory blood pressure (BP) was recorded using the fully automatic SpaceLabs 90207 oscillometric unit. Results suggested that plasma ghrelin was not related to mean ambulatory BP values. However, the highest plasma ghrelin tertile was associated with increased intraventricular septum (P=0.043) and posterior ventricular wall (P=0.002) thicknesses as well as left ventricular mass (P=0.05). After adjustment for age, sex, body mass index and systolic BP, the association persisted between ghrelin tertiles and intraventricular septum (P=0.05) and posterior ventricular wall (P=0.001) thicknesses. The SNP -501A>C polymorphism was associated with LVMI after adjustments for age, sex and systolic BP. In conclusion, ghrelin and its promoter variant are associated with cardiac hypertrophy indexes independent of BP. Positive correlation between ghrelin levels and increased wall thickness parameters may reflect compensatory up-regulation of ghrelin concentrations or direct effects of ghrelin on myocardium. The effects of the SNP seem not to be mediated through its effects on ghrelin plasma levels.
Barbieri, Andrea; Rossi, Andrea; Gaibazzi, Nicola; Erlicher, Andrea; Mureddu, Gian Francesco; Frattini, Silvia; Faden, Giacomo; Manicardi, Marcella; Beraldi, Monica; Agostini, Francesco; Lazzarini, Valentina; Moreo, Antonella; Temporelli, Pier Luigi; Faggiano, Pompilio
2018-05-23
Left ventricular hypertrophy (LVH) may reflect a wide variety of physiologic and pathologic conditions. Thus, it can be misleading to consider all LVH to be homogenous or similar. Refined 4-group classification of LVH based on ventricular concentricity and dilatation may be identified. To determine whether the 4-group classification of LVH identified distinct phenotypes, we compared their association with various noninvasive markers of cardiac stress. Cohort of unselected adult outpatients referred to a seven tertiary care echocardiographic laboratory for any indication in a 2-week period. We evaluated the LV geometric patterns using validated echocardiographic indexation methods and partition values. Standard echocardiography was performed in 1137 consecutive subjects, and LVH was found in 42%. The newly proposed 4-group classification of LVH was applicable in 88% of patients. The most common pattern resulted in concentric LVH (19%). The worst functional and hemodynamic profile was associated with eccentric LVH and those with mixed LVH had a higher prevalence of reduced EF than those with concentric LVH (P < .001 for all). The new 4-group classification of LVH system showed distinct differences in cardiac function and noninvasive hemodynamics allowing clinicians to distinguish different LV hemodynamic stress adaptations in patients with LVH. © 2018 Wiley Periodicals, Inc.
Everett, Russell J; Tastet, Lionel; Clavel, Marie-Annick; Chin, Calvin W L; Capoulade, Romain; Vassiliou, Vassilios S; Kwiecinski, Jacek; Gomez, Miquel; van Beek, Edwin J R; White, Audrey C; Prasad, Sanjay K; Larose, Eric; Tuck, Christopher; Semple, Scott; Newby, David E; Pibarot, Philippe; Dweck, Marc R
2018-06-01
Aortic stenosis is accompanied by progressive left ventricular hypertrophy and fibrosis. We investigated the natural history of these processes in asymptomatic patients and their potential reversal post-aortic valve replacement (AVR). Asymptomatic and symptomatic patients with aortic stenosis underwent repeat echocardiography and magnetic resonance imaging. Changes in peak aortic-jet velocity, left ventricular mass index, diffuse fibrosis (indexed extracellular volume), and replacement fibrosis (late gadolinium enhancement [LGE]) were quantified. In 61 asymptomatic patients (43% mild, 34% moderate, and 23% severe aortic stenosis), significant increases in peak aortic-jet velocity, left ventricular mass index, indexed extracellular volume, and LGE mass were observed after 2.1±0.7 years, with the most rapid progression observed in patients with most severe stenosis. Patients with baseline midwall LGE (n=16 [26%]; LGE mass, 2.5 g [0.8-4.8 g]) demonstrated particularly rapid increases in scar burden (78% [50%-158%] increase in LGE mass per year). In 38 symptomatic patients (age, 66±8 years; 76% men) who underwent AVR, there was a 19% (11%-25%) reduction in left ventricular mass index ( P <0.0001) and an 11% (4%-16%) reduction in indexed extracellular volume ( P =0.003) 0.9±0.3 years after surgery. By contrast midwall LGE (n=10 [26%]; mass, 3.3 g [2.6-8.0 g]) did not change post-AVR (n=10; 3.5 g [2.1-8.0 g]; P =0.23), with no evidence of regression even out to 2 years. In patients with aortic stenosis, cellular hypertrophy and diffuse fibrosis progress in a rapid and balanced manner but are reversible after AVR. Once established, midwall LGE also accumulates rapidly but is irreversible post valve replacement. Given its adverse long-term prognosis, prompt AVR when midwall LGE is first identified may improve clinical outcomes. URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01755936 and NCT01679431. © 2018 The Authors.
Risk factors for left ventricular hypertrophy: role of Na(+)-Li+ countertransport.
Neves, P L; Faisca, M; Gomes, V; Cacodcar, S; Bernardo, I; Anunciada, A I; Viegas, E; Martins, H; da Silva, A M
1996-06-01
Left ventricular hypertrophy (LVH) is associated with an increase in cardiovascular death in essential hypertension (EH). The factors involved in LVH are multiple and complex. We looked for risk factors of LVH in a group of 28 nonobese patients with EH (mean age = 45.3 years). We analyzed the activity of several erythrocyte ion transports (Vmax of NaLi countertransport, NaKCl cotransport and NaK-pump, and the Na-leak Kp Na), the intracellular Na and the insulin sensitivity index. All these parameters were used as independent variables whereas the left ventricular mass index (LVMI) was used as the dependent variable. Variables showing a significant univariate correlation (age, time of EH, mean blood pressure and Vmax of NaLi countertransport) were introduced in a stepwise multiple regression model. Only age (P = 0.014), time of EH (P = 0.038) and Vmax of NaLi countertransport (P = 0.032) were independently associated with LVMI (R2 = 0.581, P = 0.0001). The NaLi CT, an operating mode of the NaH exchanger that facilitates cellular growth, may be a marker of LVH, and consequently a marker of increased cardiovascular risk.
Essick, Eric E.; Sam, Flora
2011-01-01
Obesity and hypertension, major risk factors for the metabolic syndrome, render individuals susceptible to an increased risk of cardiovascular complications, such as adverse cardiac remodeling and heart failure. There has been much investigation into the role that an increase in the renin-angiotensin-aldosterone system (RAAS) plays in the pathogenesis of metabolic syndrome and in particular, how aldosterone mediates left ventricular hypertrophy and increased cardiac fibrosis via its interaction with the mineralocorticoid receptor (MR). Here, we review the pertinent findings that link obesity with elevated aldosterone and the development of cardiac hypertrophy and fibrosis associated with the metabolic syndrome. These studies illustrate a complex cross-talk between adipose tissue, the heart, and the adrenal cortex. Furthermore, we discuss findings from our laboratory that suggest that cardiac hypertrophy and fibrosis in the metabolic syndrome may involve cross-talk between aldosterone and adipokines (such as adiponectin). PMID:21747976
DOE Office of Scientific and Technical Information (OSTI.GOV)
Friddle, Carl J; Koga, Teiichiro; Rubin, Edward M.
2000-03-15
While cardiac hypertrophy has been the subject of intensive investigation, regression of hypertrophy has been significantly less studied, precluding large-scale analysis of the relationship between these processes. In the present study, using pharmacological models of hypertrophy in mice, expression profiling was performed with fragments of more than 3,000 genes to characterize and contrast expression changes during induction and regression of hypertrophy. Administration of angiotensin II and isoproterenol by osmotic minipump produced increases in heart weight (15% and 40% respectively) that returned to pre-induction size following drug withdrawal. From multiple expression analyses of left ventricular RNA isolated at daily time-points duringmore » cardiac hypertrophy and regression, we identified sets of genes whose expression was altered at specific stages of this process. While confirming the participation of 25 genes or pathways previously known to be altered by hypertrophy, a larger set of 30 genes was identified whose expression had not previously been associated with cardiac hypertrophy or regression. Of the 55 genes that showed reproducible changes during the time course of induction and regression, 32 genes were altered only during induction and 8 were altered only during regression. This study identified both known and novel genes whose expression is affected at different stages of cardiac hypertrophy and regression and demonstrates that cardiac remodeling during regression utilizes a set of genes that are distinct from those used during induction of hypertrophy.« less
Yang, Hao; Luo, Fangbo; Chen, Lihong; Cai, Huawei; Li, Yajiao; You, Guiying; Long, Dan; Li, Shengfu; Zhang, Qiuping; Rao, Li
2016-01-01
Aims Although extracellular-regulated kinases (ERK) are a well-known central mediator in cardiac hypertrophy, no clinically available ERK antagonist has been tested for preventing cardiac hypertrophy. Selumetinib is a novel oral MEK inhibitor that is currently under Phase II and Phase III clinical investigation for advanced solid tumors. In this study, we investigated whether Selumetinib could inhibit the aberrant ERK activation of the heart in response to stress as well as prevent cardiac hypertrophy. Methods and Results In an in vitro model of PE-induced cardiac hypertrophy, Selumetinib significantly inhibited the ERK activation and prevented enlargement of cardiomyocytes or reactivation of certain fetal genes. In the pathologic cardiac hypertrophy model of ascending aortic constriction, Selumetinib provided significant ERK inhibition in the stressed heart but not in the other organs. This selective ERK inhibition prevented left ventricular (LV) wall thickening, LV mass increase, fetal gene reactivation and cardiac fibrosis. In another distinct physiologic cardiac hypertrophy model of a swimming rat, Selumetinib provided a similar anti-hypertrophy effect, except that no significant fetal gene reactivation or cardiac fibrosis was observed. Conclusions Selumetinib, a novel oral anti-cancer drug with good safety records in a number of Phase II clinical trials, can inhibit ERK activity in the heart and prevent cardiac hypertrophy. These promising results indicate that Selumetinib could potentially be used to treat cardiac hypertrophy. However, this hypothesis needs to be validated in human clinical trials. PMID:27438013
Blood pressure and left ventricular hypertrophy during American-style football participation.
Weiner, Rory B; Wang, Francis; Isaacs, Stephanie K; Malhotra, Rajeev; Berkstresser, Brant; Kim, Jonathan H; Hutter, Adolph M; Picard, Michael H; Wang, Thomas J; Baggish, Aaron L
2013-07-30
Hypertension, a strong determinant of cardiovascular disease risk, has been documented among elite, professional American-style football (ASF) players. The risk of increased blood pressure (BP) and early adulthood hypertension among the substantially larger population of collegiate ASF athletes is not known. We conducted a prospective, longitudinal study to examine BP, the incidence of hypertension, and left ventricular remodeling among collegiate ASF athletes. Resting BP and left ventricular structure were assessed before and after a single season of competitive ASF participation in 6 consecutive groups of first-year university athletes (n=113). ASF participation was associated with significant increases in systolic BP (116±8 versus 125±13 mm Hg; P<0.001) and diastolic BP (64±8 mm Hg versus 66±10 mm Hg; P<0.001). At the postseason assessment, the majority of athletes met criteria for Joint National Commission (seventh report) prehypertension (53 of 113, 47%) or stage 1 hypertension (16 of 113, 14%). Among measured characteristics, lineman field position, intraseason weight gain, and family history of hypertension were the strongest independent predictors of postseason BP. Among linemen, there was a significant increase in the prevalence of concentric left ventricular hypertrophy (2 of 64 [3%] versus 20 of 64 [31%]; P<0.001) and change in left ventricular mass correlated with intraseason change in systolic BP (R=0.46, P<0.001). Collegiate ASF athletes may be at risk for clinically relevant increases in BP and the development of hypertension. Enhanced surveillance and carefully selected interventions may represent important opportunities to improve later-life cardiovascular health outcomes in this population.
Koo, T Y; Ahn, C; Yang, J
2017-06-01
Cardiovascular disease is the leading cause of morbidity and mortality in kidney transplantation (KT) patients. The prevalence of left ventricular hypertrophy increases with the progression of renal insufficiency. We investigated the association between the progression of renal insufficiency and left ventricular hypertrophy after KT. We reviewed KT patients at Seoul National University Hospital from January 1973 to December 2009. The creatinine elevation ratio (CER, the percentage change in the creatinine level from 1 month to 5 years after transplant) was calculated as follows: (creatinine level at 5 years minus creatinine level at 1 month)/creatinine level at 1 month × 100. The study population was classified into a high-CER group (CER ≥25%) and low-CER group (CER <25%). Mean left ventricular mass index (LVMI) values were 135.7 and 134.7 g/m 2 before KT and 101.7 and 123.7 g/m 2 at 5 years after KT in the low-CER and high-CER groups, respectively. The LVMI before or 1 year after KT was not different between the 2 groups, but the LVMI at 5 years post-transplant was higher in the high-CER group than in the low-CER group. The LVMI increased after its initial decrease in the high-CER group, whereas its reduction was maintained in the low-CER group during the 5 years after KT (P = .009, repeated-measures analysis of variance). These data suggest that deterioration of renal allograft function is associated with left ventricular remodeling after KT. Copyright © 2017 Elsevier Inc. All rights reserved.
Left ventricular geometric patterns in end-stage kidney disease: Determinants and course over time.
Nubé, Menso J; Hoekstra, Tiny; Doganer, Volkan; Bots, Michiel L; Blankestijn, Peter J; van den Dorpel, Marinus; Kamp, Otto; Ter Wee, Piet M; de Roij van Zuijdewijn, Camiel L M; Grooteman, Muriel P C
2018-02-20
While concentric left ventricular hypertrophy (cLVH) predominates in non-dialysis-dependent chronic kidney disease (CKD), eccentric left ventricular hypertrophy (eLVH) is most prevalent in dialysis-dependent CKD stage 5 (CKD5D). In these patients, the risk of sudden death is 5× higher than in individuals with cLVH. Currently, it is unknown which factors determine left ventricular (LV) geometry and how it changes over time in CKD5D. Data from participants of the CONvective TRAnsport Study who underwent serial transthoracic echocardiography were used. Based on left ventricular mass (LVM) and relative wall thickness (RWT), 4 types of left ventricular geometry were distinguished: normal, concentric remodeling, eLVH, and cLVH. Determinants of eLVH were assessed with logistic regression. Left ventricular geometry of patients who died and survived were compared. Long-term changes in RWT and LVM were evaluated with a linear mixed model. Three hundred twenty-two patients (63.1 ± 13.3 years) were included. At baseline, LVH was present in 71% (cLVH: 27%; eLVH: 44%). Prior cardiovascular disease (CVD) was positively associated with eLVH and ß-blocker use inversely. None of the putative volume parameters showed any relationship with eLVH. Although eLVH was most prevalent in non-survivors, the distribution of left ventricular geometry did not vary over time. The finding that previous CVD was positively associated with eLVH may result from the permanent high cardiac output and the strong tendency for aortic valve calcification in this group of long-term hemodialysis patients, who suffer generally also from chronic anemia and various other metabolic derangements. No association was found between eLVH and parameters of fluid balance. The distribution of left ventricular geometry did not alter over time. The assumption that LV geometry worsens over time in susceptible individuals, who then suffer from a high risk of dying, may explain these findings. © 2018 The Authors Hemodialysis International published by Wiley Periodicals, Inc. on behalf of International Society for Hemodialysis.
Kaku, T; Sakurai, S; Furuno, Y; Yashiro, A; Nakashima, Y; Kuroiwa, A
1995-08-01
We evaluated the effects of systolic anterior motion systolic anterior motion of the mitral valve on cardiac haemodynamics. Seven adult mongrel dogs in which systolic anterior motion-septal contact was observed after dobutamine administration were used. To exclude the effects of left ventricular function and morphology, a stone removal basket catheter was placed in the left ventricular outflow tract, and haemodynamics were compared with the basket closed and opened. The basket was opened five times in three dogs not showing systolic anterior motion-septal contact, but the basket itself did not effect the haemodynamics. In the seven dogs that showed systolic anterior motion-septal contact without left ventricular hypertrophy, the basket was opened a total of 33 times in the presence of various degrees of systolic anterior motion-septal contact. After opening the basket, systolic anterior motion was reduced echocardiographically, and significant (P<0.01) changes were observed in the left ventricle-aorta pressure gradient (from 68 +/- 22 to 25 +/- 15 mm Hg), the systolic ejection period (from 146 +/- 19 to 135 +/- 16 ms), and the stroke volume (SV; from 9.4 +/- 2.9 to 10.1 +/- 3.3 ml). After basket inflation, aortic pressure and aortic flow waveforms changed but the peak pressure and flow velocity did not. The temporal distribution of left ventricular ejection also definitely changed after the basket was opened. No changes were observed in the peak dp/dt, peak negative dp/dt, time constant, left ventricular end-diastolic pressure, or left atrial pressure. These observations in this animal model of systolic anterior motion without left ventricular hypertrophy suggest that: (1) there is no potential for generation of an intra-cavity gradient in the absence of systolic anterior motion of the mitral valve, so that (2) systolic anterior motion narrowed the left ventricular outflow tract and, consequently, produced the systolic ejection period, and affected the left ventricular ejection dynamics, and that (3) the basket catheter is useful because it allows these assessments in the same heart with a nearly fixed left ventricular contractility, at least in our animal model.
Cansu, Güven Barış; Yılmaz, Nusret; Yanıkoğlu, Atakan; Özdem, Sebahat; Yıldırım, Aytül Belgi; Süleymanlar, Gültekin; Altunbaş, Hasan Ali
2017-05-01
Early diagnosis and treatment of cardiovascular diseases, the most frequent cause of morbidity and mortality in acromegaly, may be an efficient approach to extending the lifespan of affected patients. Therefore, it is crucial to determine any cardiovascular diseases in the subclinical period. The study objectives were to determine markers of subclinical atherosclerosis and asses heart structure and function. This was a cross-sectional, single-center study of 53 patients with acromegaly and 22 age- and sex-matched healthy individuals. Carotid intima-media thickness (CIMT), pulse-wave velocity (PWV), and echocardiographic data were compared between these groups. CIMT and PWV were higher in the acromegaly group than in the healthy group (P = .008 and P = .002, respectively). Echocardiography showed that left ventricular diastolic dysfunction was present in 11.3% of patients. Left ventricular mass index and left atrial volume index were higher in the patients (P = .016 and P<.001, respectively). No differences in the CIMT, PWV, or echocardiographic measurements were identified between the patients with biochemically controlled and uncontrolled acromegaly and the control group. Our results showed that subclinical atherosclerosis (i.e., CIMT and PWV markers) and heart structure and function were worse in patients with acromegaly than in healthy individuals. Because there were no differences in these parameters between patients with controlled and uncontrolled acromegaly, our results suggest that the structural and functional changes do not reverse with biochemical control. AA = active acromegaly BSA = body surface area CA = biochemically controlled acromegaly CH = concentric hypertrophy CIMT = carotid intima-media thickness DBP = diastolic blood pressure DM = diabetes mellitus ECHO = echocardiography EDV = enddiastolic volume EF = ejection fraction ESV = endsystolic volume GH = growth hormone HC = healthy control HL = hyperlipidemia HT = hypertension IGF-1 = insulin-like growth factor 1 LA = left atrial LAV = left atrial volume LAVI = left atrial volume index LV = left ventricular LVDD = left ventricular diastolic dysfunction LVEF = left ventricular ejection fraction LVH = left ventricular hypertrophy LVMI = left ventricular mass index PWV = pulse-wave velocity RWT = relative wall thickness.
Krzesiński, Paweł; Uziebło-Życzkowska, Beata; Gielerak, Grzegorz; Stańczyk, Adam; Piotrowicz, Katarzyna; Piechota, Wiesław; Smurzyński, Paweł; Skrobowski, Andrzej
2017-01-01
N-terminal pro-brain natriuretic peptide (NT-proBNP) release is associated with left ventricular expansion and pressure overload. Elevation of serum levels of natriuretic peptides is observed in patients with impaired as well as preserved left ventricular systolic function. High NT-proBNP has been shown to be related not only to preload but also to increased afterload, especially blood pressure and arterial stiffness. The aim of the study was to evaluate the association of NT-proBNP and echocardiographic parameters in hypertensives with metabolic syndrome. The study group comprised 133 patients (99 men; mean age 45.9 ± 9.4 years) with at least a 3-month history of arterial hypertension (stages 1 and 2) and fulfilling the diagnostic criteria for metabolic syndrome. Following initial clinical assessment, which included NT-proBNP levels, they underwent two-dimensional echocardiography. Echocardiographic abnormalities were observed in 60 subjects (45.1%), including left ventricular diastolic dysfunction (LVDdf) in 41 (30.8%) and left ventricular hypertrophy (LVH) in 35 (26.3%). Higher NT-proBNP concentrations were observed in patients with LVH, especially in the presence of LVDdf. Further analysis demonstrated that NT-proBNP correlated negatively with septal E' (r = -0.38; p = 0.015) and heart rate (r = -0.42; p = 0.006) in patients with LVDdf, and positively with left ventricular end diastolic diameter (r = 0.46; p = 0.006) and left ventricular mass index (r = 0.49; p = 0.005) in subjects with LVH. However, the analysis of ROC curves revealed no NT-proBNP level of good sensitivity and specificity in diagnosing LVDdf/LVH (maximal area under the curve 0.571). Even a relatively low NT-proBNP concentration can be a useful marker of left ventricular hypertrophy and end-diastolic wall stretch. However, in the present study there was no NT-proBNP level of satisfactory predictive value to diagnose LV abnormalities.
Garg, Sonia; Drazner, Mark H
2016-07-01
Left ventricular hypertrophy (LVH), an important consequence of hypertension, is traditionally classified as either concentric or eccentric based on the presence or absence of increased relative wall thickness. In 2010, we proposed a novel four-tiered classification that accounted for LV dilatation in addition to LV wall thickness. The purpose of this review is to discuss the rationale for this revised classification and highlight subsequent studies that have assessed its utility. A series of recent observational studies have tested whether the four-tiered classification identifies subphenotypes of LVH with differential risk of adverse outcomes, including incident heart failure. The majority have confirmed that eccentric hypertrophy can be subdivided into a high-risk and a low-risk group based on whether LV dilatation is present. Additional studies have shown that LV dilatation is an independent risk factor for the development of heart failure. Incorporation of LV dilatation into the assessment of LVH identifies important subphenotypes within the standard two-tiered classification that have differential risk. Such refinements in the classification of LVH may yield new insights into how LVH progresses to heart failure, help identify risk factors for this transition, and improve therapeutic efforts to prevent its occurrence.
Tsai, Chuan-Te; Chang, Yung-Ming; Lin, Shu-Luan; Chen, Yueh-Sheng; Yeh, Yu-Lan; Padma, Viswanadha Vijaya; Tsai, Chin-Chuan; Chen, Ray-Jade; Ho, Tsung-Jung; Huang, Chih-Yang
2016-03-01
Angiotensin II (Ang II) is a very important cardiovascular disease inducer and may cause cardiac pathological hypertrophy and remodeling. We evaluated a Chinese traditional medicine, alpinate oxyphyllae fructus (AOF), for therapeutic efficacy for treating Ang II-induced cardiac hypertrophy. AOF has been used to treat patients with various symptoms accompanying hypertension and cerebrovascular disorders in Korea. We investigated its protective effect against Ang II-induced cytoskeletal change and hypertrophy in H9c2 cells. The results showed that treating cells with Ang II resulted in pathological hypertrophy, such as increased expression of transcription factors NFAT-3/p-NFAT-3, hypertrophic response genes (atrial natriuretic peptide [ANP] and b-type natriuretic peptide [BNP]), and Gαq down-stream effectors (PLCβ3 and calcineurin). Pretreatment with AOF (60-100 μg/mL) led to significantly reduced hypertrophy. We also found that AOF pretreatment significantly suppressed the cardiac remodeling proteins, metalloproteinase (MMP9 and MMP2), and tissue plasminogen activator (tPA), induced by Ang II challenge. In conclusion, we provide evidence that AOF protects against Ang II-induced pathological hypertrophy by specifically inhibiting the insulin-like growth factor (IGF) II/IIR-related signaling pathway in H9c2 cells. AOF might be a candidate for cardiac hypertrophy and ventricular remodeling prevention in chronic cardiovascular diseases.
NASA Technical Reports Server (NTRS)
Ding, B.; Price, R. L.; Goldsmith, E. C.; Borg, T. K.; Yan, X.; Douglas, P. S.; Weinberg, E. O.; Bartunek, J.; Thielen, T.; Didenko, V. V.;
2000-01-01
BACKGROUND: To determine potential mechanisms of the transition from hypertrophy to very early failure, we examined apoptosis in a model of ascending aortic stenosis (AS) in male FVB/n mice. METHODS AND RESULTS: Compared with age-matched controls, 4-week and 7-week AS animals (n=12 to 16 per group) had increased ratios of left ventricular weight to body weight (4.7+/-0.7 versus 3.1+/-0.2 and 5. 7+/-0.4 versus 2.7+/-0.1 mg/g, respectively, P<0.05) with similar body weights. Myocyte width was also increased in 4-week and 7-week AS mice compared with controls (19.0+/-0.8 and 25.2+/-1.8 versus 14. 1+/-0.5 microm, respectively, P<0.01). By 7 weeks, AS myocytes displayed branching with distinct differences in intercalated disk size and staining for beta(1)-integrin on both cell surface and adjacent extracellular matrix. In vivo left ventricular systolic developed pressure per gram as well as endocardial fractional shortening were similar in 4-week AS and controls but depressed in 7-week AS mice. Myocyte apoptosis estimated by in situ nick end-labeling (TUNEL) was extremely rare in 4-week AS and control mice; however, a low prevalence of TUNEL-positive myocytes and DNA laddering were detected in 7-week AS mice. The specificity of TUNEL labeling was confirmed by in situ ligation of hairpin oligonucleotides. CONCLUSIONS: Our findings indicate that myocyte apoptosis develops during the transition from hypertrophy to early failure in mice with chronic biomechanical stress and support the hypothesis that the disruption of normal myocyte anchorage to adjacent extracellular matrix and cells, a process called anoikis, may signal apoptosis.
Doğan, Tolga; Yetim, Mucahit; Çelik, Oğuzhan; Kalçık, Macit; Özcan, Oğuzhan; Doğan, İbrahim; Erenler, Ali Kemal; Bekar, Lütfü; Karavelioğlu, Yusuf
2017-12-21
Mindin was associated with diabetic nephropathy, podocyte injury, colitis, allergic asthma, liver ischaemia and reperpusion injury and ischaemic brain injury. On the other hand, it was reported as a protective factor against obesity, cardiac hypertrophy, fibrosis and remodelling. Fragmented QRS complexes (fQRS) are markers of altered ventricular depolarisation owing to a prior myocardial scar and fibrosis. In this study, we aimed to investigate mindin levels in hypertensive patients with left ventricular hypertrophy and fQRS on electrocardiography. This observational case-control study enrolled 70 (36 female) hypertensive patients with fQRS and 38 (23 female) hypertensive control patients. All patients were evaluated by transthoracic echocardiography. Mindin levels were measured by the enzyme-linked immunosorbent assay (ELISA). Clinical, echocardiographic and laboratory data were compared between patient and control groups. There was no significant difference between patient and control groups in terms of clinical, echocardiographic and routine laboratory parameters. The mindin levels were significantly higher in the patient group than controls (11.3 (7.21-19.31) vs 4.15 (2.86-6.34); p < .001). Multiple logistic regression analyses defined increased mindin levels as an independent predictor for the presence of fQRS (Odds ratio: 1.733; p = .034). Mindin levels >6.74 predicted the presence of fQRS with a sensitifity of 84.3% and specificity of 79.9% on receiver operating characteristic (ROC) curve analysis (The area under the curve:0.889; Confidence Interval: 0.827-0.951; p < .001). Mindin expressin is upregulated in hypertensive patients with fQRS complexes. In contrary to previous studies, increased mindin levels may be associated with myocardial fibrosis.
Polycystin-1 Is a Cardiomyocyte Mechanosensor That Governs L-Type Ca2+ Channel Protein Stability.
Pedrozo, Zully; Criollo, Alfredo; Battiprolu, Pavan K; Morales, Cyndi R; Contreras-Ferrat, Ariel; Fernández, Carolina; Jiang, Nan; Luo, Xiang; Caplan, Michael J; Somlo, Stefan; Rothermel, Beverly A; Gillette, Thomas G; Lavandero, Sergio; Hill, Joseph A
2015-06-16
L-type calcium channel activity is critical to afterload-induced hypertrophic growth of the heart. However, the mechanisms governing mechanical stress-induced activation of L-type calcium channel activity are obscure. Polycystin-1 (PC-1) is a G protein-coupled receptor-like protein that functions as a mechanosensor in a variety of cell types and is present in cardiomyocytes. We subjected neonatal rat ventricular myocytes to mechanical stretch by exposing them to hypo-osmotic medium or cyclic mechanical stretch, triggering cell growth in a manner dependent on L-type calcium channel activity. RNAi-dependent knockdown of PC-1 blocked this hypertrophy. Overexpression of a C-terminal fragment of PC-1 was sufficient to trigger neonatal rat ventricular myocyte hypertrophy. Exposing neonatal rat ventricular myocytes to hypo-osmotic medium resulted in an increase in α1C protein levels, a response that was prevented by PC-1 knockdown. MG132, a proteasomal inhibitor, rescued PC-1 knockdown-dependent declines in α1C protein. To test this in vivo, we engineered mice harboring conditional silencing of PC-1 selectively in cardiomyocytes (PC-1 knockout) and subjected them to mechanical stress in vivo (transverse aortic constriction). At baseline, PC-1 knockout mice manifested decreased cardiac function relative to littermate controls, and α1C L-type calcium channel protein levels were significantly lower in PC-1 knockout hearts. Whereas control mice manifested robust transverse aortic constriction-induced increases in cardiac mass, PC-1 knockout mice showed no significant growth. Likewise, transverse aortic constriction-elicited increases in hypertrophic markers and interstitial fibrosis were blunted in the knockout animals PC-1 is a cardiomyocyte mechanosensor that is required for cardiac hypertrophy through a mechanism that involves stabilization of α1C protein. © 2015 American Heart Association, Inc.
Uyar, Meral; Davutoğlu, Vedat; Aydın, Neriman; Filiz, Ayten
2013-05-01
The aim of this study is to compare metabolic syndrome with syndrome Z growing epidemic in terms of risk factors, demographic variables, and gender differences in our large cohort at southeastern area in Turkey. Data of patients admitted to sleep clinic in University of Gaziantep from January 2006 to January 2011 were retrospectively evaluated. ATP III and JNC 7 were used for defining metabolic syndrome and hypertension. Data of 761 patients were evaluated. Hypertension, diabetes mellitus, coronary artery disease, pulmonary hypertension, and left ventricular hypertrophy were more common in patients with syndrome Z than in patients without metabolic syndrome. Age, waist/neck circumferences, BMI, triglyceride, glucose, and Epworth sleepiness scale score were detected higher, whereas the minimum oxygen saturation during sleep was lower in patients with syndrome Z. Metabolic syndrome was more common in sleep apneic subjects than in controls (58 versus 30 %). Female sleep apneics showed higher rate of metabolic syndrome than those of males (74 versus 52 %). Hypertension, diabetes mellitus, coronary artery disease, and left ventricular hypertrophy were detected higher in males with syndrome Z than in males without metabolic syndrome. Snoring and excessive daytime sleepiness were detected higher in females with syndrome Z than in females without metabolic syndrome. Systemic/pulmonary hypertension, diabetes mellitus, and left ventricular hypertrophy were more common in females with syndrome Z than in females without metabolic syndrome. Complaints of headache and systemic/pulmonary hypertension were more common among females than males with syndrome Z. Female syndrome Z patients had lower minimum oxygen saturation than male patients with syndrome Z. Metabolic syndrome in sleep apneic patients is more prevalent than in controls. All metabolic syndrome parameters were significantly different among obstructive sleep apneic patients with respect to gender with more severe coronary risk factors in males.
Di Petta, Antonio; Simas, Rafael; Ferreira, Clebson L; Capelozzi, Vera L; Salemi, Vera M C; Moreira, Luiz F P; Sannomiya, Paulina
2015-10-01
Chronic obstructive pulmonary disease is often associated with chronic comorbid conditions of cardiovascular disease, diabetes mellitus and hypertension. This study aimed to investigate the effects of the association of diabetes and pulmonary emphysema on cardiac structure and function in rats. Wistar rats were divided into control non-diabetic instilled with saline (CS) or elastase (CE), diabetic instilled with saline (DS) or elastase (DE), DE treated with insulin (DEI) groups and echocardiographic measurements, morphometric analyses of the heart and lungs, and survival analysis conducted 50 days after instillation. Diabetes mellitus was induced [alloxan, 42 mg/kg, intravenously (iv)] 10 days before the induction of emphysema (elastase, 0.25 IU/100 g). Rats were treated with NPH insulin (4 IU before elastase plus 2 IU/day, 50 days). Both CE and DE exhibited similar increases in mean alveolar diameter, which are positively correlated with increases in right ventricular (RV) wall thickness (P = 0.0022), cavity area (P = 0.0001) and cardiomyocyte thickness (P = 0.0001). Diabetic saline group demonstrated a reduction in left ventricular (LV) wall, interventricular (IV) septum, cardiomyocyte thickness and an increase in cavity area, associated with a reduction in LV fractional shortening (P < 0.05), and an increase in LViv relaxation time (P < 0.05). Survival rate decreased from 80% in DS group to 40% in DE group. In conclusion, alloxan diabetes did not affect RV hypertrophy secondary to chronic emphysema, even in the presence of insulin. Diabetes per se induced left ventricular dysfunction, which was less evident in the presence of RV hypertrophy. Survival rate was substantially reduced as a consequence, at least in part, of the coexistence of RV hypertrophy and diabetic cardiomyopathy. © 2015 The Authors. International Journal of Experimental Pathology © 2015 International Journal of Experimental Pathology.
Ruppert, Mihály; Korkmaz-Icöz, Sevil; Loganathan, Sivakkanan; Jiang, Weipeng; Lehmann, Lorenz H; Oláh, Attila; Sayour, Alex Ali; Barta, Bálint András; Merkely, Béla; Karck, Matthias; Radovits, Tamás; Szabó, Gábor
2018-05-25
Sex differences in pressure overload (PO)-induced left ventricular (LV) myocardial hypertrophy (LVH) have been intensely investigated. Nevertheless, sex-related disparities of LV hemodynamics in LVH were not examined in detail. Therefore, we aimed to provide a detailed characterization of distinct aspects of LV function in male and female rats during different stages of LVH. Banding of the abdominal aorta (AB) was performed to induce PO for 6 or 12 weeks in male and female rats. Control animals underwent sham operation. The development of LVH was followed by serial echocardiography. Cardiac function was assessed by pressure-volume analysis. Cardiomyocyte hypertrophy and fibrosis were evaluated by histology. At week 6, increased LV mass index, heart weight-to-tibial length, cardiomyocyte diameter, concentric LV geometry and moderate interstitial fibrosis were detected in both male and female AB rats, indicating the development of an early stage of LVH. Functionally, at this time point, impaired active relaxation, increased contractility and preserved ventricular-arterial coupling were observed in the AB groups in both genders. In contrast, at week 12, progressive deterioration of LVH-associated structural and functional alterations occurred in male but not in female animals with sustained PO. Accordingly, at this later stage, LVH was associated with eccentric remodeling, exacerbated fibrosis and increased chamber stiffness in male AB rats. Furthermore, augmented contractility declined in male and not in female AB animals, resulting in contractility-afterload mismatch. Maintained contractility augmentation, preserved ventricular-arterial coupling and better myocardial compliance in female rats contribute to sex differences in LV function during the progression of PO-induced LVH.
2014-01-01
Background In Taiwan, DNA-based newborn screening showed a surprisingly high incidence of a cardiac Fabry mutation (IVS4 + 919G > A). The prevalence of this mutation is too high to be believed that it is a real pathogenic mutation. The purpose of this study is to identify the cardiac pathologic characteristics in patients with left ventricular hypertrophy and this mutation Methods and results Endomyocardial biopsies were obtained in 22 patients (Median age: 61, males: 17; females: 5) with left ventricular hypertrophy and the IVS4 + 919G > A mutation; five patients had not received enzyme replacement therapy (ERT) before biopsy, while the other 17 patients had received ERT from 8 months to 51 months. Except for three patients who had received ERT for more than 3 years, all other patients showed significant pathological change and globotriaosylceramide (Gb3) accumulation in their cardiomyocytes. In contrast to classical Fabry patients, no Gb3 accumulation was found in the capillary endothelial cells of any of our patients. Fourteen patients (63.6%) were found to have myofibrillolysis. Conclusions All of the untreated and most of the treated IVS4 + 919G > A patients showed typical pathological changes of Fabry disease in their cardiomyocytes. No endothelial accumulation of Gb3 was found, which is similar to the findings of several previous reports regarding later-onset Fabry disease. This result highly suggests that the IVS4 + 919G > A is a real pathogenic later-onset Fabry mutation. PMID:24980630
Yan, Yinkun; Liu, Junting; Wang, Liang; Hou, Dongqing; Zhao, Xiaoyuan; Cheng, Hong; Mi, Jie
2017-09-15
Obesity and hypertension are two risk factors of left ventricular hypertrophy (LVH) in adults. We aimed to examine the impacts of body weight and blood pressure (BP) from childhood on adult LV geometric remodeling. The study cohort consisted of 1256 adults aged 27-42years who had 2-10 measurements of body mass index (BMI) and BP from childhood in 1987 to adulthood in 2010. We calculated the cumulative and incremental values of BMI and BP from childhood to adulthood. In adulthood, four LV geometric patterns were defined based on the values of left ventricular mass index (g/m 2.7 ) and relative wall thickness: normal geometry, concentric remodeling (CR), eccentric hypertrophy (EH) and concentric hypertrophy (CH). The prevalence of abnormal LV geometric patterns in adults was 26.4% for CR, 2.0% for EH and 2.5% for CH. For childhood values, systolic BP (Odds Ratio [OR]=1.26, 95% confidence interval [CI]=1.08-1.47) but not BMI (OR=1.06, 95%CI=0.93-1.18) was associated with adult CR, whereas BMI (OR=3.53, 95%CI=2.09-5.98) but not systolic BP (OR=1.04, 95%CI=0.65-1.66) was associated with adult EH. Both childhood BMI (OR=2.69, 95%CI=1.77-4.09) and systolic BP (OR=1.64, 95%CI=1.07-2.51) were independently associated with adult CH. For adulthood, cumulative and incremental values, BMI and systolic BP were independently associated with adult CR, EH and CH. Excessive body weight and elevated BP from childhood have independent influences on the development of adult LV geometric remodeling. Copyright © 2017 Elsevier B.V. All rights reserved.
Havndrup, O; Bundgaard, H; Andersen, P S; Larsen, L A; Vuust, J; Kjeldsen, K; Christiansen, M
2000-12-01
An examination of the genetic background and phenotypic presentation of familial hypertrophic cardiomyopathy (FHC) with respect to specific mutations in the MYH7-gene encoding the cardiac beta-myosin heavy chain. Two families (n = 22) from a cohort of 67 families with FHC were studied at the National University Hospital, Rigshospitalet, Copenhagen. Clinical, non-invasive examinations of all included family members followed by molecular genetic analysis including PCR-single strand conformation polymorphism/heteroduplex (SSCP/HD) analysis and sequencing of exon 3-23 of the MYH7-gene. We found FHC associated with a missense mutation in two families, i.e. a C > G transversion at position g10124 and a G > T transversion at position g10126 causing the change of a leucine residue at codon 390 to a valine residue. The mutation is located in the actin-binding region of the beta-myosin heavy chain. The leucine residue is evolutionarily conserved in vertebrate myosins. In the two families, the phenotypic presentations in the clinically affected were characterized by asymmetric septal hypertrophy (septum diameter 18.8 (5.0) mm (mean (SD)) with only minor involvement of the left ventricular free wall (posterior wall diameter 11.0 (2.2) mm). Furthermore, the left ventricular systolic and diastolic functions were well preserved, even at a high age. The symptomatic status of the clinically affected patients depended on the presence or absence of a concomitant left ventricular outflow tract gradient. We report a novel missense mutation associated with FHC caused by a double nucleotide transversion. The penetrance of the mutation was not complete, but in clinically affected patients the mutation gives rise to an echocardiographic phenotype, predominantly characterized by pronounced septal hypertrophy.
Banerjee, Maalika M; Ramesh Iyer, V; Nandi, Deipanjan; Vetter, Victoria L; Banerjee, Anirban
2016-04-01
In the outpatient setting, children who present with syncope routinely undergo electrocardiograms (ECG). Because of concerns for hypertrophic cardiomyopathy, children with syncope meeting ECG criteria for left ventricular hypertrophy (LVH) will frequently undergo an echocardiogram. Our objectives were to determine whether Davignon criteria for ECG waves overestimate LVH in children presenting with syncope, and to study the usefulness of echocardiography in these children. We hypothesize that the Davignon criteria presently used for interpretation of ECGs overestimate LVH, resulting in unnecessary echocardiography in this clinical setting. The clinical database of The Children's Hospital of Philadelphia was evaluated from 2002 to 2012 to identify children between 9 and 16 years of age, who presented with non-exercise-induced, isolated syncope. From this group of patients, only those with clear-cut evidence of LVH (by Davignon criteria), who also underwent an echocardiogram, were selected. A total of 136 children with syncope were identified as having LVH by Davignon ECG criteria. None of these patients manifested any evidence of hypertrophic cardiomyopathy, with normal ventricular septum (average Z-score -0.68 ± 0.84), LV posterior wall (average Z-score -0.66 ± 1.18) and LV mass (average Z-score 0.52 ± 1.29). No significant correlation was found between summed RV6 plus SV1 and LV mass. Correlations between additional ECG parameters and measures of LVH by echocardiography were similarly poor. In children presenting with syncope and LVH by ECG, there was no evidence of true LVH by echocardiography. We propose that the Davignon ECG criteria for interpreting LVH in children overestimate the degree of hypertrophy in these children and the yield of echocardiography is extremely low.
Serum uric acid and target organ damage in essential hypertension
Ofori, Sandra N; Odia, Osaretin J
2014-01-01
Background Hypertension is a major risk factor for cardiovascular mortality, as it acts through its effects on target organs, such as the heart and kidneys. Hyperuricemia increases cardiovascular risk in patients with hypertension. Objective To assess the relationship between serum uric acid and target organ damage (left ventricular hypertrophy and microalbuminuria) in untreated patients with essential hypertension. Patients and methods: A cross-sectional study was carried out in 130 (85 females, 45 males) newly diagnosed, untreated patients with essential hypertension. Sixty-five healthy age- and sex-matched non-hypertensive individuals served as controls for comparison. Left ventricular hypertrophy was evaluated by cardiac ultrasound scan, and microalbuminuria was assessed in an early morning midstream urine sample by immunoturbidimetry. Blood samples were collected for assessing uric acid levels. Results Mean serum uric acid was significantly higher among the patients with hypertension (379.7±109.2 μmol/L) than in the controls (296.9±89.8 μmol/L; P<0.001), and the prevalence of hyperuricemia was 46.9% among the hypertensive patients and 16.9% among the controls (P<0.001). Among the hypertensive patients, microalbuminuria was present in 54.1% of those with hyperuricemia and in 24.6% of those with normal uric acid levels (P=0.001). Similarly, left ventricular hypertrophy was more common in the hypertensive patients with hyperuricemia (70.5% versus 42.0%, respectively; P=0.001). There was a significant linear relationship between mean uric acid levels and the number of target organ damage (none versus one versus two: P=0.012). Conclusion These results indicate that serum uric acid is associated with target organ damage in patients with hypertension, even at the time of diagnosis; thus, it is a reliable marker of cardiovascular damage in our patient population. PMID:24833906
Serum uric acid and target organ damage in essential hypertension.
Ofori, Sandra N; Odia, Osaretin J
2014-01-01
Hypertension is a major risk factor for cardiovascular mortality, as it acts through its effects on target organs, such as the heart and kidneys. Hyperuricemia increases cardiovascular risk in patients with hypertension. To assess the relationship between serum uric acid and target organ damage (left ventricular hypertrophy and microalbuminuria) in untreated patients with essential hypertension. A cross-sectional study was carried out in 130 (85 females, 45 males) newly diagnosed, untreated patients with essential hypertension. Sixty-five healthy age- and sex-matched non-hypertensive individuals served as controls for comparison. Left ventricular hypertrophy was evaluated by cardiac ultrasound scan, and microalbuminuria was assessed in an early morning midstream urine sample by immunoturbidimetry. Blood samples were collected for assessing uric acid levels. Mean serum uric acid was significantly higher among the patients with hypertension (379.7±109.2 μmol/L) than in the controls (296.9±89.8 μmol/L; P<0.001), and the prevalence of hyperuricemia was 46.9% among the hypertensive patients and 16.9% among the controls (P<0.001). Among the hypertensive patients, microalbuminuria was present in 54.1% of those with hyperuricemia and in 24.6% of those with normal uric acid levels (P=0.001). Similarly, left ventricular hypertrophy was more common in the hypertensive patients with hyperuricemia (70.5% versus 42.0%, respectively; P=0.001). There was a significant linear relationship between mean uric acid levels and the number of target organ damage (none versus one versus two: P=0.012). These results indicate that serum uric acid is associated with target organ damage in patients with hypertension, even at the time of diagnosis; thus, it is a reliable marker of cardiovascular damage in our patient population.
Iio, Chiharuko; Inoue, Katsuji; Nishimura, Kazuhisa; Fujii, Akira; Nagai, Takayuki; Suzuki, Jun; Okura, Takafumi; Higaki, Jitsuo; Ogimoto, Akiyoshi
2015-12-01
The pathological process of left ventricular (LV) hypertrophy is associated with left atrial (LA) remodeling. This study was aimed to evaluate the prognostic value of LA strain parameters in patients with pathological LV hypertrophy. This study included 95 patients with hypertensive heart disease (HHD: n = 24), hypertrophic cardiomyopathy (HCM: n = 56), cardiac amyloidosis (CA: n = 15), and control subjects (n = 20). We used two-dimensional speckle tracking echocardiography (STE) to analyze LA global strain. LA electromechanical conduction time (EMT) at the septal (EMT-septal) and lateral wall (EMT-lateral), and their time difference (EMT-diff) were calculated. The incidence of cardiac death and heart failure hospitalization was defined as major cardiac events and that of atrial fibrillation as secondary outcome. Left atrial volume index was increased and LA booster strain was decreased in the HCM and CA groups compared with the HHD group. EMT-lateral was increased in the diseased groups compared with the control. EMT-diff was prolonged in the CA group compared with the HCM group. During the follow-up period (mean 3.4 years), major cardiac events and atrial fibrillation occurred in 17 and 13 patients, respectively. The occurrence of atrial fibrillation was associated with CA etiology, E/e', LA volume index, LAa, and EMT-lateral. The incidence of major cardiac events was independently correlated with LA volume index and EMT-diff in multivariate analysis. This study suggested that the EMT-diff could discriminate patients with a high risk of cardiac events among patients with pathological LV hypertrophy. © 2015, Wiley Periodicals, Inc.
Left ventricular mass in elite olympic weight lifters.
Lalande, Sophie; Baldi, James Christopher
2007-10-01
The existence of resistance training-induced left ventricular (LV) concentric hypertrophy is equivocal. Although some have described significant LV hypertrophy, others have suggested that training-induced LV hypertrophy is proportional to increased fat free mass (FFM) and thus a normal physiologic response to training. Method limitations, steroid use, and type of training may contribute to discrepant findings. Thus, LV structure and volumes are determined using magnetic resonance imaging. Body composition was determined using dual-energy x-ray absorptiometry in 9 elite Olympic weight lifters and 10 age- and weight-matched recreationally active controls. LV structure and volumes were determined by acquiring 6 short- and 3 long-axis magnetic resonance imaging scans of the left ventricle, whereas LV wall thickness was defined as the average of 6 midventricular segment thickness measurements. Weight lifters had the same age, weight, and FFM, but were shorter and had a greater body mass index than controls. LV mass was not different in weight lifters and controls, but was lower in weight lifters when indexed to FFM (2.56 +/- 0.07 vs 2.30 +/- 0.05, p = 0.01). LV mass correlated with FFM (r = 0.49, p = 0.04). However, LV mass was lower in weight lifters for a given FFM. LV wall thickness, as well as end-diastolic, end-systolic, and stroke volumes, were not different between groups. In conclusion, these results refute the hypothesis that resistance training induces LV concentric hypertrophy and suggest that Olympic weight lifting is associated with increases in FFM without a concomitant increase in LV mass.
Sysa-Shah, Polina; Sørensen, Lars L; Abraham, M Roselle; Gabrielson, Kathleen L
2015-01-01
Electrocardiography is an important method for evaluation and risk stratification of patients with cardiac hypertrophy. We hypothesized that the recently developed transgenic mouse model of cardiac hypertrophy (ErbB2tg) will display distinct ECG features, enabling WT (wild type) mice to be distinguished from transgenic mice without using conventional PCR genotyping. We evaluated more than 2000 mice and developed specific criteria for genotype determination by using cageside ECG, during which unanesthetized mice were manually restrained for less than 1 min. Compared with those from WT counterparts, the ECG recordings of ErbB2tg mice were characterized by higher P- and R-wave amplitudes, broader QRS complexes, inverted T waves, and ST interval depression. Pearson's correlation matrix analysis of combined WT and ErbB2tg data revealed significant correlation between heart weight and the ECG parameters of QT interval (corrected for heart rate), QRS interval, ST height, R amplitude, P amplitude, and PR interval. In addition, the left ventricular posterior wall thickness as determined by echocardiography correlated with ECG-determined ST height, R amplitude, QRS interval; echocardiographic left ventricular mass correlated with ECG-determined ST height and PR interval. In summary, we have determined phenotypic ECG criteria to differentiate ErbB2tg from WT genotypes in 98.8% of mice. This inexpensive and time-efficient ECG-based phenotypic method might be applied to differentiate between genotypes in other rodent models of cardiac hypertrophy. Furthermore, with appropriate modifications, this method might be translated for use in other species. PMID:26310459
NASA Astrophysics Data System (ADS)
Gulothungan, G.; Malathi, R.
2018-04-01
Disturbed sodium (Na+) and calcium (Ca2+) handling is known to be a major predisposing factor for life-threatening cardiac arrhythmias. Cardiac contractility in ventricular tissue is prominent by Ca2+ channels like voltage dependent Ca2+ channels, sodium-calcium exchanger (Na+-Ca2+x) and sacroplasmicrecticulum (SR) Ca2+ pump and leakage channels. Experimental and clinical possibilities for studying cardiac arrhythmias in human ventricular myocardium are very limited. Therefore, the use of alternative methods such as computer simulations is of great importance. Our aim of this article is to study the impact on action potential (AP) generation and propagation in single ventricular myocyte and ventricular tissue under different dysfunction Ca2+ channels condition. In enhanced activity of Na+-Ca2+x, single myocyte produces AP duration (APD90) and APD50 is significantly smaller (266 ms and 235 ms). Its Na+-Ca2+x current at depolarization is increases 60% from its normal level and repolarization current goes more negative (nonfailing= -0.28 pA/pF and failing= -0.47 pA/pF). Similarly, same enhanced activity of Na+-Ca2+x in 10 mm region of ventricular sheet, raises the plateau potential abruptly, which ultimately affects the diastolic repolarization. Compare with normal ventricular sheet region of 10 mm, 10% of ventricular sheet resting state is reduces and ventricular sheet at time 250 ms is goes to resting state very early. In hypertrophy condition, single myocyte produces APD90 and APD50 is worthy of attention smaller (232 mS and 198 ms). Its sodium-potassium (Na+-K+) pump current is 75% reduces from its control conditions (0.13 pA/pF). Hypertrophy condition, 50% of ventricular sheet is reduces to minimum plateau potential state, that starts the repolarization process very early and reduces the APD. In a single failing SR Ca2+ channels myocyte, recovery of Ca2+ concentration level in SR reduces upto 15% from its control myocytes. At time 290 ms, 70% of ventricular sheet is in dysfunction resting potential state in the range -83 mV and ventricular sheet at time 295 ms is goes to 65% dysfunction resting state. Therefore we concluded that shorter APD, instability resting potential and affected calcium induced calcium release (CICR) due to dysfunction Ca2+ channels is potentially have a substantial effect on cardiac contractility and relaxation. Computational study on ventricular tissue AP and its underlying ionic channel currents could help to elucidate possible arrhythmogenic mechanism on a cellular level.
Ventricular dysfunction in children with obstructive sleep apnea: radionuclide assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tal, A.; Leiberman, A.; Margulis, G.
Ventricular function was evaluated using radionuclide ventriculography in 27 children with oropharyngeal obstruction and clinical features of obstructive sleep apnea. Their mean age was 3.5 years (9 months to 7.5 years). Conventional clinical assessment did not detect cardiac involvement in 25 of 27 children; however, reduced right ventricular ejection fraction (less than 35%) was found in 10 (37%) patients (mean: 19.5 +/- 2.3% SE, range: 8-28%). In 18 patients wall motion abnormality was detected. In 11 children in whom radionuclide ventriculography was performed before and after adenotonsillectomy, right ventricular ejection fraction rose from 24.4 +/- 3.6% to 46.7 +/- 3.4%more » (P less than 0.005), and in all cases wall motion showed a definite improvement. In five children, left ventricular ejection fraction rose greater than 10% after removal of oropharyngeal obstruction. It is concluded that right ventricular function may be compromised in children with obstructive sleep apnea secondary to adenotonsillar hypertrophy, even before clinical signs of cardiac involvement are present.« less
Cheng, Yusheng; Gong, Yan; Qian, Shuai; Mou, Yi; Li, Hanrui; Chen, Xijing; Kong, Hui; Xie, Weiping; Wang, Hong; Zhang, Yihua; Huang, Zhangjian
2018-02-22
Given the clinical therapeutic efficacy of oral-dosed bardoxolone methyl (1) and the selective vasodilatory effect caused by inhalation of nitric oxide (NO) on pulmonary arterial hypertension (PAH) patients, a new hybrid (CDDO-NO, 2) from 1 and NO donor isosorbide 5-mononitrate (3) was designed and synthesized. This hybrid could liberate 1 and NO in the lungs of rats after trachea injection. Significantly, 2 lowered mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP), decreased right ventricular hypertrophy (RVH), and attenuated pulmonary artery medial thickness (PAMT) and vascular muscularization in monocrotaline (MCT)-induced PAH rats. Meanwhile, 2 inhibited overproliferation of perivascular cells and diminished macrophage infiltration and oxidative stress by inactivation of NOX4. In addition, 2 markedly reduced cardiac hypertrophy and fibrosis in the PAH rats. Overall, 2 exhibited potent dual activities of pulmonary vasodilation and vascular remodeling inhibition, suggesting that it may be a promising agent for PAH intervention.
The role of intraventricular vortices in the left ventricular filling?
NASA Astrophysics Data System (ADS)
Martinez-Legazpi, Pablo; Bermejo, Javier; Benito, Yolanda; Alhama, Marta; Yotti, Raquel; Perez Del Villar, Candelas; Gonzalez-Mansilla, Ana; Barrio, Alicia; Fernandez-Aviles, Francisco; Del Alamo, Juan Carlos
2013-11-01
The generation of vortices during early filling is a salient feature of left ventricular hemodynamics. Existing clinical data suggest that these intraventricular vortices may facilitate pulling flow from the left atrium. To test this hypothesis, we have quantitatively dissected the contribution of the vortex to intraventricular pressure gradients by isolating its induced flow in ultrasound-derived data in 20 patients with non-ischemic dilated cardiomyopathy (NIDCM), 20 age-matched healthy controls and 20 patients with hypertrophied cardiomyopathy. We have observed that, in patients with NIDCM, the hemodynamic forces were shown to be partially supported by the flow inertia whereas that effect was minimized in healthy hearts. In patients with hypertrophied cardiomiopathy such effect was not observed. Supported by grants, PIS09/02603, RD06/0010 (RECAVA), CM12/00273 (to CPV) and BA11/00067 (to JB) from the Instituto de Salud Carlos III, Spain. PML and JCA were partially supported by NIH grant 1R21 HL108268-01.
Anderson-Fabry disease in heart failure.
Akhtar, M M; Elliott, P M
2018-06-16
Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by mutations in the GLA gene that result in deficiency of the enzyme alpha-galactosidase A. The worldwide incidence of Fabry's disease is reported to be in the range of 1 in 40,000-117,000, although this value may be a significant underestimate given under recognition of symptoms and delayed or missed diagnosis. Deficiency in alpha-galactosidase A causes an accumulation of neutral glycosphingolipids such as globotriaosylceramide (Gb3) in lysosomes within various tissues including the vascular endothelium, kidneys, heart, eyes, skin and nervous system. Gb3 accumulation induces pathology via the release of pro-inflammatory cytokines, growth-promoting factors and by oxidative stress, resulting in myocardial extracellular matrix remodelling, left ventricular hypertrophy (LVH), vascular dysfunction and interstitial fibrosis. Cardiac involvement manifesting as ventricular hypertrophy, systolic and diastolic dysfunction, valvular abnormalities and conduction tissue disease is common in AFD and is associated with considerable cardiovascular morbidity and mortality from heart failure, sudden cardiac death and stroke-related death.
Pearson, Anthony C
2017-07-01
Localized thickening of the basal portion of the ventricular septum or basal septal hypertrophy (BSH) has been identified both at autopsy and by imaging studies for decades; despite numerous investigations, there is no consensus on the significance of this finding and a remarkable lack of consistency in terminology. This paper summarizes the scientific literature on the topic, focusing on recent echocardiographic findings. A case description illustrating some of the complex issues involved in measurement and diagnosis and differentiation from sigmoidal hypertrophic cardiomyopathy (HCM) is presented. Criteria are proposed for diagnosing pathologic BSH which include the following: (1) Exertional symptoms compatible with left ventricular outflow tract obstruction (LVOTO) such as dyspnea, near-syncope, and chest discomfort; (2) Documented LVOTO gradient demonstrated at peak bicycle or post-treadmill exercise >30 mm Hg; and (3) Symptomatic improvement with β-blocker (or other negative inotropic) therapy (preferably accompanied by documentation of reduction of exercise-induced LVOT). © 2017, Wiley Periodicals, Inc.
Estimation of left ventricular mass in conscious dogs
NASA Technical Reports Server (NTRS)
Coleman, Bernell; Cothran, Laval N.; Ison-Franklin, E. L.; Hawthorne, E. W.
1986-01-01
A method for the assessment of the development or the regression of left ventricular hypertrophy (LVH) in a conscious instrumented animal is described. First, the single-slice short-axis area-length method for estimating the left-ventricular mass (LVM) and volume (LVV) was validated in 24 formaldehyde-fixed canine hearts, and a regression equation was developed that could be used in the intact animal to correct the sonomicrometrically estimated LVM. The LVM-assessment method, which uses the combined techniques of echocardiography and sonomicrometry (in conjunction with the regression equation), was shown to provide reliable and reproducible day-to-day estimates of LVM and LVV, and to be sensitive enough to detect serial changes during the development of LVH.
Nelson, O. Lynne; Rourke, Bryan C.
2013-01-01
SUMMARY Deep hibernators such as golden-mantled ground squirrels (Callospermophilus lateralis) have multiple challenges to cardiac function during low temperature torpor and subsequent arousals. As heart rates fall from over 300 beats min−1 to less than 10, chamber dilation and reduced cardiac output could lead to congestive myopathy. We performed echocardiography on a cohort of individuals prior to and after several months of hibernation. The left ventricular chamber exhibited eccentric and concentric hypertrophy during hibernation and thus calculated ventricular mass was ~30% greater. Ventricular ejection fraction was mildly reduced during hibernation but stroke volumes were greater due to the eccentric hypertrophy and dramatically increased diastolic filling volumes. Globally, the systolic phase in hibernation was ~9.5 times longer, and the diastolic phase was 28× longer. Left atrial ejection generally was not observed during hibernation. Atrial ejection returned weakly during early arousal. Strain echocardiography assessed the velocity and total movement distance of contraction and relaxation for regional ventricular segments in active and early arousal states. Myocardial systolic strain during early arousal was significantly greater than the active state, indicating greater total contractile movement. This mirrored the increased ventricular ejection fraction noted with early arousal. However, strain rates were slower during early arousal than during the active period, particularly systolic strain, which was 33% of active, compared with the rate of diastolic strain, which was 67% of active. As heart rate rose during the arousal period, myocardial velocities and strain rates also increased; this was matched closely by cardiac output. Curiously, though heart rates were only 26% of active heart rates during early arousal, the cardiac output was nearly 40% of the active state, suggesting an efficient pumping system. We further analyzed proportions of cardiac myosin heavy-chain (MyHC) isoforms in a separate cohort of squirrels over 5 months, including time points before hibernation, during hibernation and just prior to emergence. Hibernating individuals were maintained in both a 4°C cold room and a 20°C warm room. Measured by SDS-PAGE, relative percentages of cardiac MyHC alpha were increased during hibernation, at both hibernacula temperatures. A potential increase in contractile speed, and power, from more abundant MyHC alpha may aid force generation at low temperature and at low heart rates. Unlike many models of cardiomyopathies where the alpha isoform is replaced by the beta isoform in order to reduce oxygen consumption, ground squirrels demonstrate a potential cardioprotective mechanism to maintain cardiac output during torpor. PMID:24072796
Darouian, Navid; Aro, Aapo L; Narayanan, Kumar; Uy-Evanado, Audrey; Rusinaru, Carmen; Reinier, Kyndaron; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S
2017-07-01
The Romhilt-Estes point score system (RE) is an established ECG criterion for diagnosing left ventricular hypertrophy (LVH). In this study, we assessed for the first time, whether RE and its components are predictive of sudden cardiac arrest (SCA) independent of left ventricular (LV) mass. Sudden cardiac arrest (SCA) cases occurring between 2002 and 2014 in a Northwestern US metro region (catchment area approx. 1 million) were compared to geographic controls. ECGs and echocardiograms performed prior to the SCA and those of controls were acquired from the medical records and evaluated for the ECG criteria established in the RE score and for LV mass. Two hundred forty-seven SCA cases (age 68.3 ± 14.6, male 64.4%) and 330 controls (age 67.4 ± 11.5, male 63.6) were included in the analysis. RE scores were greater in cases than controls (2.5 ± 2.1 vs. 1.9 ± 1.7, p < .001), and SCA cases were more likely to meet definite LVH criteria (18.6% vs. 7.9%, p < .001). In a multivariable model including echocardiographic LVH and LV function, definite LVH remained independently predictive of SCA (OR 2.04, 95% CI 1.16-3.59, p = .013). The model was replicated with the individual ECG criteria, and only SV 1.2 ≥ 30 mm and delayed intrinsicoid deflection remained significant predictors of SCA. Left ventricular hypertrophy (LVH) as defined by the RE point score system is associated with SCA independent of echocardiographic LVH and reduced LV ejection fraction. These findings support an independent role for purely electrical LVH, in the genesis of lethal ventricular arrhythmias. © 2017 Wiley Periodicals, Inc.
BMP type I receptor ALK2 is required for angiotensin II-induced cardiac hypertrophy
Spagnolli, Ester; Ernande, Laura; Thoonen, Robrecht; Kolodziej, Starsha A.; Leyton, Patricio A.; Cheng, Juan; Tainsh, Robert E. T.; Mayeur, Claire; Rhee, David K.; Wu, Mei. X.; Scherrer-Crosbie, Marielle; Buys, Emmanuel S.; Zapol, Warren M.; Bloch, Kenneth D.; Bloch, Donald B.
2016-01-01
Bone morphogenetic protein (BMP) signaling contributes to the development of cardiac hypertrophy. However, the identity of the BMP type I receptor involved in cardiac hypertrophy and the underlying molecular mechanisms are poorly understood. By using quantitative PCR and immunoblotting, we demonstrated that BMP signaling increased during phenylephrine-induced hypertrophy in cultured neonatal rat cardiomyocytes (NRCs), as evidenced by increased phosphorylation of Smads 1 and 5 and induction of Id1 gene expression. Inhibition of BMP signaling with LDN193189 or noggin, and silencing of Smad 1 or 4 using small interfering RNA diminished the ability of phenylephrine to induce hypertrophy in NRCs. Conversely, activation of BMP signaling with BMP2 or BMP4 induced hypertrophy in NRCs. Luciferase reporter assay further showed that BMP2 or BMP4 treatment of NRCs repressed atrogin-1 gene expression concomitant with an increase in calcineurin protein levels and enhanced activity of nuclear factor of activated T cells, providing a mechanism by which BMP signaling contributes to cardiac hypertrophy. In a model of cardiac hypertrophy, C57BL/6 mice treated with angiotensin II (A2) had increased BMP signaling in the left ventricle. Treatment with LDN193189 attenuated A2-induced cardiac hypertrophy and collagen deposition in left ventricles. Cardiomyocyte-specific deletion of BMP type I receptor ALK2 (activin-like kinase 2), but not ALK1 or ALK3, inhibited BMP signaling and mitigated A2-induced cardiac hypertrophy and left ventricular fibrosis in mice. The results suggest that BMP signaling upregulates the calcineurin/nuclear factor of activated T cell pathway via BMP type I receptor ALK2, contributing to cardiac hypertrophy and fibrosis. PMID:26873969
Blakeslee, Weston W.; Demos-Davies, Kimberly M.; Lemon, Douglas D.; Lutter, Katharina M.; Cavasin, Maria A.; Payne, Sam; Nunley, Karin; Long, Carlin S.; McKinsey, Timothy A.; Miyamoto, Shelley D.
2017-01-01
Background Histone deacetylase (HDAC) inhibitors are promising therapeutics for various forms of cardiac disease. The purpose of this study was to assess cardiac HDAC catalytic activity and expression in children with single ventricle heart disease of right ventricular morphology (SV), as well as in a rodent model of right ventricular hypertrophy (RVH). Methods Homogenates of RV explants from non-failing controls and SV children were assayed for HDAC catalytic activity and HDAC isoform expression. Postnatal 1-day old rat pups were placed in hypoxic conditions and echocardiographic analysis, gene expression, HDAC catalytic activity and isoform expression studies of the RV were performed. Results Class I, IIa, and IIb HDAC catalytic activity and protein expression were elevated in hearts of SV children. Hypoxic neonatal rats demonstrated RVH, abnormal gene expression and elevated class I and class IIb HDAC catalytic activity and protein expression in the RV compared to control. Conclusions These data suggest that myocardial HDAC adaptations occur in the SV heart and could represent a novel therapeutic target. While further characterization of the hypoxic neonatal rat is needed, this animal model may be suitable for pre-clinical investigations of pediatric RV disease and could serve as a useful model for future mechanistic studies. PMID:28549058
A Benign Cardiac Growth but Not So Indolent
Reddy, Sahadev T.; Biederman, Robert W. W.
2016-01-01
Cardiac lipomatous hypertrophy is a rare benign condition that usually involves the interatrial septum. Due to its benign nature it rarely requires intervention. Its presence outside the interatrial septum is reported infrequently. We present a case of lipomatous hypertrophy in the intraventricular septum that was complicated by a severe, symptomatic, and disabling dynamic left ventricular outflow tract obstruction. The symptoms significantly improved following the excision of the mass. In our case transthoracic echocardiogram was used to visualize the mass and measure the severity of the obstruction; Cardiac Magnetic Resonance Imaging was used to characterize the mass and histopathology confirmed the diagnosis. PMID:27293911
Does Resistance Training Stimulate Cardiac Muscle Hypertrophy?
ERIC Educational Resources Information Center
Bloomer, Richard J.
2003-01-01
Reviews the literature on the left ventricular structural adaptations induced by resistance/strength exercise, focusing on human work, particularly well-trained strength athletes engaged in regular, moderate- to high-intensity resistance training (RT). The article discusses both genders and examines the use of anabolic-androgenic steroids in…
Blood Pressure and Left Ventricular Remodeling Among American Style Football Players
Lin, Jeffrey; Wang, Francis; Weiner, Rory B.; DeLuca, James R.; Wasfy, Meagan M.; Berkstresser, Brant; Lewis, Gregory D.; Hutter, Adolph M.; Picard, Michael H.; Baggish, Aaron L.
2016-01-01
Objective To determine the relationships between American style football (ASF) participation, acquired left ventricular (LV) hypertrophy, and LV systolic function as assessed using contemporary echocardiographic parameters. Background Participation in ASF has been associated with the development of hypertension and LV hypertrophy. To what degree these processes impact LV function is unknown. Methods This is a prospective, longitudinal, cohort study evaluating NCAA Division I collegiate football athletes stratified by field position (linemen, n=30 vs. non-linemen, n=57) before and after a single competitive season with transthoracic echocardiography. LV systolic function was measured using complementary parameters of global longitudinal strain (GLS, 2D speckle-tracking) and ejection fraction (EF, 2D biplane). Results ASF participation was associated with field position-specific increases in systolic blood pressure (linemen Δ SBP = 10±8 mmHg vs. non-linemen Δ SBP = 3±7 mmHg, p<0.001) and an overall increase in incident LV hypertrophy (pre = 8% vs. post = 25%, p<0.05). Linemen who developed LV hypertrophy had concentric geometry (9/11, 82%) with decreased GLS (Δ = −1.1%, p<0.001) while non-linemen demonstrated eccentric LV hypertrophy (8/10, 80%) with increased GLS (Δ = +1.4%, p<0.001). In contrast, LV ejection fraction in the total cohort and when stratified by field position was not significantly affected by ASF participation. Among the total cohort, lineman field position, postseason weight, systolic blood pressure, average LV wall thickness, and relative wall thickness were all independent predictors of postseason GLS. Conclusions ASF participation at a lineman field position may lead to a form of sport-related myocardial remodeling that is pathologic rather than adaptive. Future study will be required to determine if targeted efforts to control blood pressure, minimize weight gain, and to include an element of aerobic conditioning in this subset of athletes may attenuate this process and translate into tangible downstream health benefits. PMID:27931524
Inhibition of glycogen synthase kinase 3beta during heart failure is protective.
Hirotani, Shinichi; Zhai, Peiyong; Tomita, Hideharu; Galeotti, Jonathan; Marquez, Juan Pablo; Gao, Shumin; Hong, Chull; Yatani, Atsuko; Avila, Jesús; Sadoshima, Junichi
2007-11-26
Glycogen synthase kinase (GSK)-3, a negative regulator of cardiac hypertrophy, is inactivated in failing hearts. To examine the histopathological and functional consequence of the persistent inhibition of GSK-3beta in the heart in vivo, we generated transgenic mice with cardiac-specific overexpression of dominant negative GSK-3beta (Tg-GSK-3beta-DN) and tetracycline-regulatable wild-type GSK-3beta. GSK-3beta-DN significantly reduced the kinase activity of endogenous GSK-3beta, inhibited phosphorylation of eukaryotic translation initiation factor 2B epsilon, and induced accumulation of beta-catenin and myeloid cell leukemia-1, confirming that GSK-3beta-DN acts as a dominant negative in vivo. Tg-GSK-3beta-DN exhibited concentric hypertrophy at baseline, accompanied by upregulation of the alpha-myosin heavy chain gene and increases in cardiac function, as evidenced by a significantly greater Emax after dobutamine infusion and percentage of contraction in isolated cardiac myocytes, indicating that inhibition of GSK-3beta induces well-compensated hypertrophy. Although transverse aortic constriction induced a similar increase in hypertrophy in both Tg-GSK-3beta-DN and nontransgenic mice, Tg-GSK-3beta-DN exhibited better left ventricular function and less fibrosis and apoptosis than nontransgenic mice. Induction of the GSK-3beta transgene in tetracycline-regulatable wild-type GSK-3beta mice induced left ventricular dysfunction and premature death, accompanied by increases in apoptosis and fibrosis. Overexpression of GSK-3beta-DN in cardiac myocytes inhibited tumor necrosis factor-alpha-induced apoptosis, and the antiapoptotic effect of GSK-3beta-DN was abrogated in the absence of myeloid cell leukemia-1. These results suggest that persistent inhibition of GSK-3beta induces compensatory hypertrophy, inhibits apoptosis and fibrosis, and increases cardiac contractility and that the antiapoptotic effect of GSK-3beta inhibition is mediated by myeloid cell leukemia-1. Thus, downregulation of GSK-3beta during heart failure could be compensatory.
Mutlak, Michael; Schlesinger-Laufer, Michal; Haas, Tali; Shofti, Rona; Ballan, Nimer; Lewis, Yair E; Zuler, Mor; Zohar, Yaniv; Caspi, Lilac H; Kehat, Izhak
2018-05-24
Chronic pressure overload and a variety of mediators induce concentric cardiac hypertrophy. When prolonged, cardiac hypertrophy culminates in decreased myocardial function and heart failure. Activation of the extracellular signal-regulated kinase (ERK) is consistently observed in animal models of hypertrophy and in human patients, but its role in the process is controversial. We generated transgenic mouse lines with cardiomyocyte restricted overexpression of intrinsically active ERK1, which similar to the observations in hypertrophy is phosphorylated on both the TEY and the Thr207 motifs and is overexpressed at pathophysiological levels. The activated ERK1 transgenic mice developed a modest adaptive hypertrophy with increased contractile function and without fibrosis. Following induction of pressure-overload, where multiple pathways are stimulated, this activation did not further increase the degree of hypertrophy but protected the heart through a decrease in the degree of fibrosis and maintenance of ventricular contractile function. The ERK pathway acts to promote a compensated hypertrophic response, with enhanced contractile function and reduced fibrosis. The activation of this pathway may be a therapeutic strategy to preserve contractile function when the pressure overload cannot be easily alleviated. The inhibition of this pathway, which is increasingly being used for cancer therapy on the other hand, should be used with caution in the presence of pressure-overload. Copyright © 2017. Published by Elsevier B.V.
Wu, Jing; Wu, Caiqin; Fan, Wenjing; Zhou, Jie; Xu, Ling
2017-01-14
Left ventricular (LV) remodeling is closely linked to the progression of heart failure. There are limited data on the epidemiology of new onset LV remodeling among elderly women, which requires further investigation. We examined data from a community-based cohort of women aged > 65 years, who had received > 2 echocardiography scans from 2009 to 2014. Exclusion criteria for patients included prior echocardiographic evidence of left ventricular enlargement (LVE) or hypertrophy (LVH). LVE was defined as the index of left ventricular internal diameter at end-diastole to height, and LVH was defined as the left ventricular mass and thickness index which indicate hypertrophy. Of the 474 subjects (age 71.85 ± 6.47 years), 49 (10.3%) developed LVH, while 55 (11.6%) developed LVE during the mean follow-up period of 5 years. Independent predictors of LVH included: central blood pressure (CBP, per 10 mmHg) [HR 1.094, 95% CI 1.011-1.202], BMI˃25(kg/m 2 )[HR 1.306, 95% CI 1.175-1.434], B-type natriuretic peptide (BNP) ≥ 100 (pg/mL) [HR 1.635, 95% CI 1.107-3.311] and brachial-ankle pulse wave velocity (baPWV) ≥16 m/s [HR 1.605, 95% CI 1.474-2.039]. Predictors of LVE were CBP (per 10 mmHg) [HR 1.121, 95% CI 1.027-1.238], BMI˃25(kg/m 2 )[HR 1.302, 95% CI 1.173-1.444], Low-density lipoprotein cholesterol (LDL-C) [HR 1.193, 95%CI 1.013-1.405] and E/e' ratio [HR 1.077, 95% CI 1.017-1.140]. CBP and BMI were demonstrated to be independent and robust predictors of left ventricular remodeling among elderly women, including both LVE and LVH. BNP and baPWV were specifically related to the development of LVH, whereas LDL-C and E/e' ratio were related to LVE.
Li, Zhao; Liu, Yamin; Guo, Xiaofan; Sun, Guozhe; Ma, Qun; Dai, Ying; Zhu, Guangshuo; Sun, Yingxian
2018-05-21
In numerous diseases, abnormal expression of myocardial infarction‑associated transcript (MIAT) has been reported to be involved in cell proliferation, apoptosis and migration. However, whether this long non‑coding RNA MIAT has a regulatory effect on heart hypertrophy requires further investigation. To this end, the present study evaluated MIAT in hypertrophic cardiomyocytes in vitro and in vivo. Neonatal rat ventricular myocytes (NRVMs) were induced by isoproterenol (ISO) to create a cell hypertrophy model, and mice were intraperitoneally injected with ISO to establish an animal model. Echocardiography, immunofluorescence staining, western blot analysis, RNA isolation and reverse transcription‑polymerase chain reaction were applied to test the involvement of MIAT in cardiac hypertrophy. The results revealed that MIAT was upregulated under ISO stimulation at the mRNA level both in vivo and in vitro. Silencing of MIAT resulted in decreased expression levels of atrial natriuretic peptide and brain natriuretic peptide in ISO‑treated NRVM cardiomyocytes, confirming the connection between MIAT and hypertrophy. Furthermore, MIAT small interfering RNA significantly increased microRNA (miR)‑150 and decreased P300 expression in NRVMs. In conclusion, the MIAT/miR‑150‑5p axis targets P300 as a positive regulator of cardiomyocyte hypertrophy.
Fernandes, T; Soci, U P R; Oliveira, E M
2011-09-01
Among the molecular, biochemical and cellular processes that orchestrate the development of the different phenotypes of cardiac hypertrophy in response to physiological stimuli or pathological insults, the specific contribution of exercise training has recently become appreciated. Physiological cardiac hypertrophy involves complex cardiac remodeling that occurs as an adaptive response to static or dynamic chronic exercise, but the stimuli and molecular mechanisms underlying transduction of the hemodynamic overload into myocardial growth are poorly understood. This review summarizes the physiological stimuli that induce concentric and eccentric physiological hypertrophy, and discusses the molecular mechanisms, sarcomeric organization, and signaling pathway involved, also showing that the cardiac markers of pathological hypertrophy (atrial natriuretic factor, β-myosin heavy chain and α-skeletal actin) are not increased. There is no fibrosis and no cardiac dysfunction in eccentric or concentric hypertrophy induced by exercise training. Therefore, the renin-angiotensin system has been implicated as one of the regulatory mechanisms for the control of cardiac function and structure. Here, we show that the angiotensin II type 1 (AT1) receptor is locally activated in pathological and physiological cardiac hypertrophy, although with exercise training it can be stimulated independently of the involvement of angiotensin II. Recently, microRNAs (miRs) have been investigated as a possible therapeutic approach since they regulate the translation of the target mRNAs involved in cardiac hypertrophy; however, miRs in relation to physiological hypertrophy have not been extensively investigated. We summarize here profiling studies that have examined miRs in pathological and physiological cardiac hypertrophy. An understanding of physiological cardiac remodeling may provide a strategy to improve ventricular function in cardiac dysfunction.
Simko, F; Matúsková, J; Lupták, I; Pincíková, T; Krajcírovicová, K; Stvrtina, S; Pomsár, J; Pelouch, V; Paulis, L; Pechánová, O
2007-01-01
Aldosterone receptor antagonist, spironolactone, has been shown to prevent remodeling of the heart in several models of left ventricular hypertrophy. The aim of the present study was to determine whether the treatment with spironolactone can prevent hypertension, reduction of tissue nitric oxide synthase activity and left ventricular (LV) and aortic remodeling in N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. Four groups of rats were investigated: control, spironolactone (200 mg/kg), L-NAME (40 mg/kg) and L-NAME + spironolactone (in corresponding dosage). Animals were studied after 5 weeks of treatment. The decrease of NO-synthase activity in the LV and kidney was associated with the development of hypertension and LV hypertrophy, with increased DNA concentration in the LV, and remodeling of the aorta in the L-NAME group. Spironolactone prevented the inhibition of NO-synthase activity in the LV and kidney and partially attenuated hypertension and LVH development and the increase in DNA concentration. However, remodeling of the aorta was not prevented by spironolactone treatment. We conclude that the aldosterone receptor antagonist spironolactone improved nitric oxide production and partially prevented hypertension and LVH development without preventing hypertrophy of the aorta in NO-deficient hypertension. The reactive growth of the heart and aorta seems to be controlled by different mechanisms in L-NAME-induced hypertension.
De Cobelli, Francesco; Esposito, Antonio; Belloni, Elena; Pieroni, Maurizio; Perseghin, Gianluca; Chimenti, Cristina; Frustaci, Andrea; Del Maschio, Alessandro
2009-03-01
Fabry's disease may be difficult to differentiate from symmetric hypertrophic cardiomyopathy. Our aim was to compare the myocardial location and distribution patterns of delayed enhancement between patients with Fabry's disease who are affected by symmetric myocardial hypertrophy and patients with symmetric hypertrophic cardiomyopathy in order to identify a specific sign to best differentiate the two diseases. Patients with Fabry's disease-related hypertrophy showed left ventricular (LV) delayed enhancement with a typical and consistently found pattern characterized by the involvement of the inferolateral basal or mid basal segments and a mesocardial distribution that spared the subendocardium. This pattern seems to be specific to Fabry's disease; in fact, patients with symmetric hypertrophic cardiomyopathy had variable locations and distributions of delayed enhancement. These observations may contribute to identifying Fabry's disease as a specific cause of symmetric hypertrophy.
Díaz-Arrieta, Gustavo; Mendoza-Hernández, María Elsa; Pacheco-Aranda, Erika; Rivas-Duro, Miguel; Robles-Parra, Héctor Manuel; Espinosa-Vázquez, Raúl Arturo; Hernández-Cabrera, Jorge
2010-01-01
In diabetic patients with chronic renal failure (CRF) treated with dialysis, the diastolic and systolic left ventricular dysfunction is frequent. The aim was to assess by echocardiography the prevalence of diastolic and systolic ventricular dysfunction in diabetic patients with CRF treated with continuous ambulatory peritoneal dialysis (CAPD). Sixty diabetic patients with CRF in CAPD were studied. The mean age was 54.5 +/- 12 years (27-78 years). The left ventricular filling pattern (LVFP) as a diastolic function parameter and left ventricular ejection fraction (LVEF) as a systolic function parameter were measured by transthoracic echocardiography. Descriptive statistical analysis was used. 27 (45 %) patients were women and 33 (55 %) were men. In 55 (91.7 %) left ventricular concentric hypertrophy was observed. Fifty-two patients (86.7 %) showed LVFP type I; three (5 %) had the type II; two (3.3 %) showed pseudonormal pattern and three (5 %) had a normal LVFP. The LVEF was 0.63 +/- 0.09 (CI = 0.41-0.82). Forty nine (81.7 %) patients had LVEF equal or greater than 0.55. The prevalence of diastolic left ventricular dysfunction was 95 % and the prevalence of systolic left ventricular dysfunction was 18.3%.
Losartan Potassium: A Review of Its Suitability for Use in Military Aircrew
2001-06-01
blood volume and/or sodium load to the kidney, and and diabetic nephropathy. Besides blocking the increased sympathetic nervous system activity...potassium levels, although no patient needed to left ventricular hypertrophy (LVH) similar to that discontinue the drug due to hyperkalemia . seen with ACE
1991-02-01
evidence of isolated hypertrophy compatible with athletic training. c. Left or right bundle branch block. d. Wolff - Parkinson - White or other pre-excitation... syndrome . e. Second or third-degree heart block. (Atrio-ventricular dissociation post-stress is not necessarily disqualifying.) f. QT-prolongation (QTc
GDF11 Does not Rescue Aging-Related Pathological Hypertrophy
Smith, Shavonn C.; Zhang, Xiaoxiao; Zhang, Xiaoying; Gross, Polina; Starosta, Timothy; Mohsin, Sadia; Franti, Michael; Gupta, Priyanka; Hayes, David; Myzithras, Maria; Kahn, Julius; Tanner, James; Weldon, Steven M.; Khalil, Ashraf; Guo, Xinji; Sabri, Abdelkarim; Chen, Xiongwen; MacDonnell, Scott; Houser, Steven R.
2015-01-01
Rationale GDF11 (Growth Differentiation Factor 11) is a member of the transforming growth factor β (TGFβ) super family of secreted factors. A recent study showed that reduced GDF11 blood levels with aging was associated with pathological cardiac hypertrophy (PCH), and restoring GDF11 to normal levels in old mice rescued PCH. Objective To determine if and by what mechanism GDF11 rescues aging dependent PCH. Methods and Results 24-month-old C57BL/6 mice were given a daily injection of either recombinant (r) GDF11 at 0.1mg/kg or vehicle for 28 days. rGDF11 bioactivity was confirmed in-vitro. After treatment, rGDF11 levels were significantly increased but there was no significant effect on either heart weight (HW) or body weight (BW). HW/BW ratios of old mice were not different from 8 or 12 week-old animals, and the PCH marker ANP was not different in young versus old mice. Ejection fraction, internal ventricular dimension, and septal wall thickness were not significantly different between rGDF11 and vehicle treated animals at baseline and remained unchanged at 1, 2 and 4 weeks of treatment. There was no difference in myocyte cross-sectional area rGDF11 versus vehicle-treated old animals. In vitro studies using phenylephrine-treated neonatal rat ventricular myocytes (NRVM), to explore the putative anti-hypertrophic effects of GDF11, showed that GDF11 did not reduce NRVM hypertrophy, but instead induced hypertrophy. Conclusions Our studies show that there is no age-related PCH in disease free 24-month-old C57BL/6 mice and that restoring GDF11 in old mice has no effect on cardiac structure or function. PMID:26383970
Decreased cardiac L-type Ca2+ channel activity induces hypertrophy and heart failure in mice
Goonasekera, Sanjeewa A.; Hammer, Karin; Auger-Messier, Mannix; Bodi, Ilona; Chen, Xiongwen; Zhang, Hongyu; Reiken, Steven; Elrod, John W.; Correll, Robert N.; York, Allen J.; Sargent, Michelle A.; Hofmann, Franz; Moosmang, Sven; Marks, Andrew R.; Houser, Steven R.; Bers, Donald M.; Molkentin, Jeffery D.
2011-01-01
Antagonists of L-type Ca2+ channels (LTCCs) have been used to treat human cardiovascular diseases for decades. However, these inhibitors can have untoward effects in patients with heart failure, and their overall therapeutic profile remains nebulous given differential effects in the vasculature when compared with those in cardiomyocytes. To investigate this issue, we examined mice heterozygous for the gene encoding the pore-forming subunit of LTCC (calcium channel, voltage-dependent, L type, α1C subunit [Cacna1c mice; referred to herein as α1C–/+ mice]) and mice in which this gene was loxP targeted to achieve graded heart-specific gene deletion (termed herein α1C-loxP mice). Adult cardiomyocytes from the hearts of α1C–/+ mice at 10 weeks of age showed a decrease in LTCC current and a modest decrease in cardiac function, which we initially hypothesized would be cardioprotective. However, α1C–/+ mice subjected to pressure overload stimulation, isoproterenol infusion, and swimming showed greater cardiac hypertrophy, greater reductions in ventricular performance, and greater ventricular dilation than α1C+/+ controls. The same detrimental effects were observed in α1C-loxP animals with a cardiomyocyte-specific deletion of one allele. More severe reductions in α1C protein levels with combinatorial deleted alleles produced spontaneous cardiac hypertrophy before 3 months of age, with early adulthood lethality. Mechanistically, our data suggest that a reduction in LTCC current leads to neuroendocrine stress, with sensitized and leaky sarcoplasmic reticulum Ca2+ release as a compensatory mechanism to preserve contractility. This state results in calcineurin/nuclear factor of activated T cells signaling that promotes hypertrophy and disease. PMID:22133878
Left Ventricular Mass and Geometry and the Risk of Ischemic Stroke
Di Tullio, Marco R.; Zwas, Donna R.; Sacco, Ralph L.; Sciacca, Robert R.; Homma, Shunichi
2009-01-01
Background and Purpose Left ventricular hypertrophy (LVH) is a risk factor for cardiovascular events, but its effect on ischemic stroke risk is established mainly in whites. The effect of LV geometry on stroke risk has not been defined. The aim of the present study was to evaluate whether LVH and LV geometry are independently associated with increased ischemic stroke risk in a multiethnic population. Methods A population-based case-control study was conducted on 394 patients with first ischemic stroke and 413 age-, sex-, and race-ethnicity–matched community control subjects. LV mass was measured by transthoracic echocardiography. LV geometric patterns (normal, concentric remodeling, concentric or eccentric hypertrophy) were identified. Stroke risk associated with LVH and different LV geometric patterns was assessed by conditional logistic regression analysis in the overall group and age, sex, and race-ethnic strata, with adjustment for established stroke risk factors. Results Concentric hypertrophy carried the greatest stroke risk (adjusted odds ratio [OR], 3.5; 95% confidence interval [CI], 2.0 to 6.2), followed by eccentric hypertrophy (adjusted OR, 2.4; 95% CI, 2.0 to 4.3). Concentric remodeling carried slightly increased stroke risk (adjusted OR, 1.7; 95% CI, 1.0 to 2.9). Increased LV relative wall thickness was independently associated with stroke after adjustment for LV mass (OR, 1.6; 95% CI, 1.1 to 2.3). Conclusions LVH and abnormal LV geometry are independently associated with increased stroke risk. LVH is strongly associated with ischemic stroke in all age, sex, and race-ethnic subgroups. Increased LV relative wall thickness imparts an increased stroke risk after adjustment for LV mass and is of additional value in stroke risk prediction. PMID:12958319
Bond, A R; Iacobazzi, D; Abdul-Ghani, S; Ghorbel, M T; Heesom, K J; George, S J; Caputo, M; Suleiman, M-S; Tulloh, R M
2018-03-20
Right ventricle (RV) remodelling occurs in neonatal patients born with ventricular septal defect (VSD). The presence of a defect between the two ventricles allows for shunting of blood from the left to right side. The resulting RV hypertrophy leads to molecular remodelling which has thus far been largely investigated using right atrial (RA) tissue. In this study we used proteomic and phosphoproteomic analysis in order to determine any difference between the proteomes for RA and RV. Samples were therefore taken from the RA and RV of five infants (0.34 ± 0.05 years, mean ± SEM) with VSD who were undergoing cardiac surgery to repair the defect. Significant differences in protein expression between RV and RA were seen. 150 protein accession numbers were identified which were significantly lower in the atria, whereas none were significantly higher in the atria compared to the ventricle. 19 phosphorylation sites (representing 19 phosphoproteins) were also lower in RA. This work has identified differences in the proteome between RA and RV which reflect differences in contractile activity and metabolism. As such, caution should be used when drawing conclusions based on analysis of the RA and extrapolating to the hypertrophied RV. RV hypertrophy occurs in neonatal patients born with VSD. Very little is known about how the atria responds to RV hypertrophy, especially at the protein level. Access to tissue from age-matched groups of patients is very rare, and we are in the unique position of being able to get tissue from both the atria and ventricle during reparative surgery of these infants. Our findings will be beneficial to future research into heart chamber malformations in congenital heart defects. Copyright © 2018. Published by Elsevier B.V.
Teo, Karen SL; Dundon, Benjamin K; Molaee, Payman; Williams, Kerry F; Carbone, Angelo; Brown, Michael A; Worthley, Matthew I; Disney, Patrick J; Sanders, Prashanthan; Worthley, Stephen G
2008-01-01
Background Percutaneous closure of atrial septal defects (ASDs) should potentially reduce right heart volumes by removing left-to-right shunting. Due to ventricular interdependence, this may be associated with impaired left ventricular filling and potentially function. Furthermore, atrial changes post-ASD closure have been poorly understood and may be important for understanding risk of atrial arrhythmia post-ASD closure. Cardiovascular magnetic resonance (CMR) is an accurate and reproducible imaging modality for the assessment of cardiac function and volumes. We assessed cardiac volumes pre- and post-percutaneous ASD closure using CMR. Methods Consecutive patients (n = 23) underwent CMR pre- and 6 months post-ASD closure. Steady state free precession cine CMR was performed using contiguous slices in both short and long axis views through the ASD. Data was collected for assessment of left and right atrial, ventricular end diastolic volumes (EDV) and end systolic volumes (ESV). Data is presented as mean ± SD, volumes as mL, and paired t-testing performed between groups. Statistical significance was taken as p < 0.05. Results There was a significant reduction in right ventricular volumes at 6 months post-ASD closure (RVEDV: 208.7 ± 76.7 vs. 140.6 ± 60.4 mL, p < 0.0001) and RVEF was significantly increased (RVEF 35.5 ± 15.5 vs. 42.0 ± 15.2%, p = 0.025). There was a significant increase in the left ventricular volumes (LVEDV 84.8 ± 32.3 vs. 106.3 ± 38.1 mL, p = 0.003 and LVESV 37.4 ± 20.9 vs. 46.8 ± 18.5 mL, p = 0.016). However, there was no significant difference in LVEF and LV mass post-ASD closure. There was a significant reduction in right atrial volumes at 6 months post-ASD closure (pre-closure 110.5 ± 55.7 vs. post-closure 90.7 ± 69.3 mL, p = 0.019). Although there was a trend to a decrease in left atrial volumes post-ASD closure, this was not statistically significant (84.5 ± 34.8 mL to 81.8 ± 44.2 mL, p = NS). Conclusion ASD closure leads to normalisation of ventricular volumes and also a reduction in right atrial volume. Further follow-up is required to assess how this predicts outcomes such as risk of atrial arrhythmias after such procedures. PMID:19040763
Ambia, Anne M; Morgan, Jamie L; Wells, C Edward; Roberts, Scott W; Sanghavi, Monika; Nelson, David B; Cunningham, F Gary
2018-05-01
Adverse maternal outcomes associated with chronic hypertension include accelerated hypertension and resultant target organ damage. One example is long-standing hypertension leading to maternal cardiac dysfunction. Our group has previously identified that features of such injury manifest as cardiac remodeling with left ventricular hypertrophy. Moreover, these features of cardiac remodeling identified in women with chronic hypertension during pregnancy were associated with adverse perinatal outcomes. Recent definitions of maternal cardiac remodeling using echocardiography have been expanded to include measurements of wall thickness. We hypothesized that these new features characterizing cardiac remodeling in women with chronic hypertension may also be associated with adverse perinatal outcomes. There were 3 aims in this study of women with treated chronic hypertension during pregnancy: to (1) apply the updated definitions of maternal cardiac remodeling; (2) elucidate whether these features of cardiac remodeling were associated with adverse perinatal outcomes; and (3) determine which, if any, of the newly defined cardiac remodeling strata were most damaging when compared to women with normal cardiac geometry. This was a retrospective study of women with treated chronic hypertension during pregnancy delivered from January 2009 through January 2016. Cardiac remodeling was categorized by left ventricular mass index and relative wall thickness into 4 groups determined using the 2015 American Society of Echocardiography guidelines: normal geometry, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. Perinatal outcomes were analyzed according to each category of cardiac remodeling compared with outcomes in women with normal geometry. A total of 314 women with treated chronic hypertension underwent echocardiography at a mean gestational age of 17.9 weeks. There were no differences between maternal age (P = .896), habitus (P = .36), or duration of chronic hypertension (P = .212) among the 4 groups. Abnormal cardiac remodeling was found in 51% and was significantly associated with increased rates of superimposed preeclampsia (P = .015), preterm birth (P < .001), and neonatal intensive care admission (P = .003). These outcomes reached the greatest significance when comparisons were made between eccentric hypertrophy and normal geometry. Using current American Society of Echocardiography guidelines, 51% of women with treated chronic hypertension during pregnancy have some degree of abnormal cardiac remodeling. Any suggestion of maternal cardiac remodeling, regardless of subtype, was associated with increased risks for superimposed preeclampsia and preterm birth with its resultant perinatal sequelae. Eccentric ventricular hypertrophy, previously thought to mimic exercise physiology, appears to be the most associated with adverse perinatal outcomes. Despite evidence of cardiac remodeling, ejection fraction was preserved. Copyright © 2018 Elsevier Inc. All rights reserved.
Okada, Seigo; Muneuchi, Jun; Origuchi, Hideki
2018-01-01
A 21-year-old man with Wolff-Parkinson-White syndrome and aneurysmal septal dyskinesis underwent radiofrequency catheter ablation of the accessory pathways. Before radiofrequency catheter ablation, the activation wavefront arose from the aneurysmal septum, whereas the propagation of the left ventricle was normalised after radiofrequency catheter ablation. These findings demonstrate the importance of the electro-mechanical interaction in patients with Wolff-Parkinson-White syndrome and ventricular dysfunction.
De Pergola, Giovanni; Nardecchia, Adele; Giagulli, Vito Angelo; Triggiani, Vincenzo; Guastamacchia, Edoardo; Minischetti, Manuela Castiglione; Silvestris, Franco
2013-03-01
Epidemiological studies have recently shown that obesity, and abdominal obesity in particular, is an independent risk factor for the development of heart failure (HF). Higher cardiac oxidative stress is the early stage of heart dysfunction due to obesity, and it is the result of insulin resistance, altered fatty acid and glucose metabolism, and impaired mitochondrial biogenesis. Extense myocyte hypertrophy and myocardial fibrosis are early microscopic changes in patients with HF, whereas circumferential strain during the left ventricular (LV) systole, LV increase in both chamber size and wall thickness (LV hypertrophy), and LV dilatation are the early macroscopic and functional alterations in obese developing heart failure. LV hypertrophy leads to diastolic dysfunction and subendocardial ischemia in obesity, and pericardial fat has been shown to be significantly associated with LV diastolic dysfunction. Evolving abnormalities of diastolic dysfunction may include progressive hypertrophy and systolic dysfunction, and various degrees of eccentric and/or concentric LV hypertrophy may be present with time. Once HF is established, overweight and obese have a better prognosis than do their lean counterparts with the same level of cardiovascular disease, and this phenomenon is called "obesity paradox". It is mainly due to lower muscle protein degradation, brain natriuretic peptide circulating levels and cardio-respiratory fitness than normal weight patients with HF.
Rodilla, Enrique; Costa, José A; Martín, Joaquin; González, Carmen; Pascual, Jose M; Redon, Josep
2014-03-20
The principal objective was to assess the prevalence of left ventricular hypertrophy (LVH) in hypertensive, never treated patients, depending on adjustment for body surface or height. Secondary objectives were to determine geometric alterations of the left ventricle and to analyze the interdependence of hypertension and obesity to induce LVH. Cross-sectional study that included 750 patients (387 men) aged 47 (13, SD) years who underwent ambulatory blood pressure (ABPM) monitoring and echocardiography. The prevalence of LVH was 40.4% (303 patients), adjusted for body surface area (BSA, LVHBSA), and 61.7% (463 patients), adjusted for height(2.7) (LVHheight(2.7)). In a multivariate logistic analysis, systolic BP24h, gender and presence of elevated microalbuminuria were associated with both LVHBSA and LVHheight(2.7). Increased waist circumference was the strongest independent predictor of LVHheight(2.7), but was not associated with LVHBSA. We found a significant interaction between abdominal obesity and systolic BP24h in LVHheight(2.7). Concentric remodelling seems to be the most prevalent alteration of left ventricular geometry in early stages of hypertension (37.5%). The impact of obesity as predictor of LVH in never treated hypertensives is present only when left ventricular mass (LVM) is indexed to height(2.7). Obesity interacts with systolic BP24h in an additive but not merely synergistic manner. Systolic BP24h is the strongest determinant of LVH when indexed for BSA. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Evaristi, Maria Francesca; Caubère, Céline; Harmancey, Romain; Desmoulin, Franck; Peacock, William Frank; Berry, Matthieu; Turkieh, Annie; Barutaut, Manon; Galinier, Michel; Dambrin, Camille; Polidori, Carlo; Miceli, Cristina; Chamontin, Bernard; Koukoui, François; Roncalli, Jerôme; Massabuau, Pierre; Smih, Fatima; Rouet, Philippe
2016-11-01
About 77.9 million (1 in 4) American adults have high blood pressure. High blood pressure is the primary cause of left ventricular hypertrophy (LVH), which represents a strong predictor of future heart failure and cardiovascular mortality. Previous studies have shown an altered metabolic profile in hypertensive patients with LVH. The goal of this study was to identify blood metabolomic LVH biomarkers by H NMR to provide novel diagnostic tools for rapid LVH detection in populations of hypertensive individuals. This cross-sectional study included 48 hypertensive patients with LVH matched with 48 hypertensive patients with normal LV size, and 24 healthy controls. Two-dimensional targeted M-mode echocardiography was performed to measure left ventricular mass index. Partial least squares discriminant analysis was used for the multivariate analysis of the H NMR spectral data. From the H NMR-based metabolomic profiling, signals coming from methylene (-CH2-) and methyl (-CH3) moieties of aliphatic chains from plasma lipids were identified as discriminant variables. The -CH2-/-CH3 ratio, an indicator of the mean length of the aliphatic lipid chains, was significantly higher (P < 0.001) in the LVH group than in the hypertensive group without LVH and controls. Receiver operating characteristic curve showed that a cutoff of 2.34 provided a 52.08% sensitivity and 85.42% specificity for discriminating LVH (AUC = 0.703, P-value < 0.001). We propose the -CH2-/-CH3 ratio from plasma aliphatic lipid chains as a biomarker for the diagnosis of left ventricular remodeling in hypertension.
NASA Technical Reports Server (NTRS)
Koide, M.; Nagatsu, M.; Zile, M. R.; Hamawaki, M.; Swindle, M. M.; Keech, G.; DeFreyte, G.; Tagawa, H.; Cooper, G. 4th; Carabello, B. A.
1997-01-01
BACKGROUND: When a pressure overload is placed on the left ventricle, some patients develop relatively modest hypertrophy whereas others develop extensive hypertrophy. Likewise, the occurrence of contractile dysfunction also is variable. The cause of this heterogeneity is not well understood. METHODS AND RESULTS: We recently developed a model of gradual proximal aortic constriction in the adult canine that mimicked the heterogeneity of the hypertrophic response seen in humans. We hypothesized that differences in outcome were related to differences present before banding. Fifteen animals were studied initially. Ten developed left ventricular dysfunction (dys group). Five dogs maintained normal function (nl group). At baseline, the nl group had a lower mean systolic wall stress (96 +/- 9 kdyne/cm2; dys group, 156 +/- 7 kdyne/cm2; P < .0002) and greater relative left ventricular mass (left ventricular weight [g]/body wt [kg], 5.1 +/- 0.36; dys group, 3.9 +/- 0.26; P < .02). On the basis of differences in mean systolic wall stress at baseline, we predicted outcome in the next 28 dogs by using a cutoff of 115 kdyne/cm2. Eighteen of 20 dogs with baseline mean systolic stress > 115 kdyne/cm2 developed dysfunction whereas 6 of 8 dogs with resting stress < or = 115 kdyne/cm2 maintained normal function. CONCLUSIONS: We conclude that this canine model mimicked the heterogeneous hypertrophic response seen in humans. In the group that eventually developed dysfunction there was less cardiac mass despite 60% higher wall stress at baseline, suggesting a different set point for regulating myocardial growth in the two groups.
Effects of Obesity on Cardiovascular Hemodynamics, Cardiac Morphology, and Ventricular Function.
Alpert, Martin A; Omran, Jad; Bostick, Brian P
2016-12-01
Obesity produces a variety of hemodynamic alterations that may cause changes in cardiac morphology which predispose to left and right ventricular dysfunction. Various neurohormonal and metabolic alterations commonly associated with obesity may contribute to these abnormalities of cardiac structure and function. These changes in cardiovascular hemodynamics, cardiac morphology, and ventricular function may, in severely obese patients, predispose to heart failure, even in the absence of other forms of heart disease (obesity cardiomyopathy). In normotensive obese patients, cardiac involvement is commonly characterized by elevated cardiac output, low peripheral vascular resistance, and increased left ventricular (LV) end-diastolic pressure. Sleep-disordered breathing may lead to pulmonary arterial hypertension and, in association with left heart failure, may contribute to elevation of right heart pressures. These alterations, in association with various neurohormonal and metabolic abnormalities, may produce LV hypertrophy; impaired LV diastolic function; and less commonly, LV systolic dysfunction. Many of these alterations are reversible with substantial voluntary weight loss.
The left ventricle in aortic stenosis--imaging assessment and clinical implications.
Călin, Andreea; Roşca, Monica; Beladan, Carmen Cristiana; Enache, Roxana; Mateescu, Anca Doina; Ginghină, Carmen; Popescu, Bogdan Alexandru
2015-04-29
Aortic stenosis has an increasing prevalence in the context of aging population. In these patients non-invasive imaging allows not only the grading of valve stenosis severity, but also the assessment of left ventricular function. These two goals play a key role in clinical decision-making. Although left ventricular ejection fraction is currently the only left ventricular function parameter that guides intervention, current imaging techniques are able to detect early changes in LV structure and function even in asymptomatic patients with significant aortic stenosis and preserved ejection fraction. Moreover, new imaging parameters emerged as predictors of disease progression in patients with aortic stenosis. Although proper standardization and confirmatory data from large prospective studies are needed, these novel parameters have the potential of becoming useful tools in guiding intervention in asymptomatic patients with aortic stenosis and stratify risk in symptomatic patients undergoing aortic valve replacement.This review focuses on the mechanisms of transition from compensatory left ventricular hypertrophy to left ventricular dysfunction and heart failure in aortic stenosis and the role of non-invasive imaging assessment of the left ventricular geometry and function in these patients.
NASA Astrophysics Data System (ADS)
Jung, Wulf-Ingo; Sieverding, Ludger; Breuer, Johannes; Schmidt, Oliver; Widmaier, Stefan; Bunse, Michael; van Erckelens, Franz; Apitz, Jürgen; Dietze, Guenther J.; Lutz, Otto
1998-07-01
Proton-decoupled31P NMR spectroscopy at 1.5 T of the anterior left ventricular myocardium was used to monitor myocardial phosphate metabolism in asymptomatic patients with hypertrophic cardiomyopathy (HCM,n= 14) and aortic stenosis (AS,n= 12). In addition to the well-known phosphorus signals a phosphomonoester (PME) signal was detected at about 6.9 ppm in 7 HCM and 2 AS patients. This signal was not observed in the spectra of normal controls (n= 11). We suggest that in spectra of patients with myocardial hypertrophy the presence of a PME signal reflects alterations in myocardial glucose metabolism.
NASA Technical Reports Server (NTRS)
Stroud, Jason D.; Baicu, Catalin F.; Barnes, Mary A.; Spinale, Francis G.; Zile, Michael R.
2002-01-01
To determine whether and to what extent one component of the extracellular matrix, fibrillar collagen, contributes causally to abnormalities in viscoelasticity, collagen was acutely degraded by activation of endogenous matrix metalloproteinases (MMPs) with the serine protease plasmin. Papillary muscles were isolated from normal cats and cats with right ventricular pressure overload hypertrophy (POH) induced by pulmonary artery banding. Plasmin treatment caused MMP activation, collagen degradation, decreased the elastic stiffness constant, and decreased the viscosity constant in both normal and POH muscles. Thus, whereas many mechanisms may contribute to the abnormalities in myocardial viscoelasticity in the POH myocardium, changes in fibrillar collagen appear to play a predominant role.
Huang, Bao-Tao; Peng, Yong; Liu, Wei; Zhang, Chen; Huang, Fang-Yang; Wang, Peng-Ju; Zuo, Zhi-Liang; Liao, Yan-Biao; Chai, Hua; Li, Qiao; Zhao, Zhen-Gang; Luo, Xiao-Lin; Ren, Xin; Huang, Kai-Sen; Meng, Qing-Tao; Chen, Chi; Huang, De-Jia; Chen, Mao
2015-03-01
Although inappropriate left ventricular mass has been associated with clustered cardiac geometric and functional abnormalities, its predictive value in patients with coronary artery disease is still unknown. This study examined the association of inappropriate left ventricular mass with clinical outcomes in patients with angina pectoris and normal ejection fraction. Consecutive patients diagnosed with angina pectoris whose ejection fraction was normal were recruited from 2008 to 2012. Inappropriate left ventricular mass was determined when the ratio of actual left ventricular mass to the predicted one exceeded 150%. The primary endpoint was a composite of all-cause death, nonfatal myocardial infarction, and nonfatal stroke. Clinical outcomes between the inappropriate and appropriate left ventricular mass group were compared before and after propensity matching. Of the total of 1515 participants, 18.3% had inappropriate left ventricular mass. Patients with inappropriate left ventricular mass had a higher composite event rate compared with those with appropriate left ventricular mass (11.2 vs. 6.6%, P=0.010). Multivariate Cox regression analyses showed that inappropriate left ventricular mass was an independent risk factor for adverse events (adjusted hazard ratio, 1.59; 95% confidence interval, 1.03-2.45; P=0.035). The worse outcome in patients with inappropriate left ventricular mass was further validated in a propensity matching cohort and patients with the traditional definition of left ventricular hypertrophy. Inappropriate left ventricular mass was associated with an increased risk of adverse events in patients with angina pectoris and normal ejection fraction.
Fatty acid utilization in pressure-overload hypertrophied rat hearts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reibel, D.K.; O'Rourke, B.
1986-03-05
The authors have previously shown that the levels of total tissue coenzyme A and carnitine are reduced in hypertrophied hearts of rats subjected to aortic constriction. It was therefore of interest to determine if these changes were associated with alterations in fatty acid oxidation by the hypertrophied myocardium. Hearts were excised from sham-operated and aortic-constricted rats and perfused at 10 cm H/sub 2/O left atrial filling pressure with a ventricular afterload of 80 cm of H/sub 2/O with buffer containing 1.2 mM /sup 14/C-linoleate. Heart rate and peak systolic pressure were not different in control and hypertrophied hearts. /sup 14/CO/submore » 2/ production was linear in both groups of hearts between 10 and 30 minutes of perfusion. The rate of fatty acid oxidation determined by /sup 14/CO/sub 2/ production during this time was 0.728 +/- 0.06 ..mu..moles/min/g dry in control hearts and 0.710 +/- 0.02 ..mu..moles/min/g dry in hypertrophied hearts. Comparable rates of fatty acid oxidation were associated with comparable rates of O/sub 2/ consumption in the two groups of hearts (39.06 +/- 3.50 and 36.78 +/- 2.39 ..mu..moles/g dry/min for control and hypertrophied hearts, respectively). The data indicate that the ability of the hypertrophied heart to oxidize fatty acids under these perfusion conditions is not impaired in spite of significant reductions in tissue levels of coenzyme A and carnitine.« less
Smith, Nicola J; Chan, Hsiu-Wen; Qian, Hongwei; Bourne, Allison M; Hannan, Katherine M; Warner, Fiona J; Ritchie, Rebecca H; Pearson, Richard B; Hannan, Ross D; Thomas, Walter G
2011-05-01
Major interest surrounds how angiotensin II triggers cardiac hypertrophy via epidermal growth factor receptor transactivation. G protein-mediated transduction, angiotensin type 1 receptor phosphorylation at tyrosine 319, and β-arrestin-dependent scaffolding have been suggested, yet the mechanism remains controversial. We examined these pathways in the most reductionist model of cardiomyocyte growth, neonatal ventricular cardiomyocytes. Analysis with [(32)P]-labeled cardiomyocytes, wild-type and [Y319A] angiotensin type 1 receptor immunoprecipitation and phosphorimaging, phosphopeptide analysis, and antiphosphotyrosine blotting provided no evidence for tyrosine phosphorylation at Y319 or indeed of the receptor, and mutation of Y319 (to A/F) did not prevent either epidermal growth factor receptor transactivation in COS-7 cells or cardiomyocyte hypertrophy. Instead, we demonstrate that transactivation and cardiomyocyte hypertrophy are completely abrogated by loss of G-protein coupling, whereas a constitutively active angiotensin type 1 receptor mutant was sufficient to trigger transactivation and growth in the absence of ligand. These results were supported by the failure of the β-arrestin-biased ligand SII angiotensin II to transactivate epidermal growth factor receptor or promote hypertrophy, whereas a β-arrestin-uncoupled receptor retained these properties. We also found angiotensin II-mediated cardiomyocyte hypertrophy to be attenuated by a disintegrin and metalloprotease inhibition. Thus, G-protein coupling, and not Y319 phosphorylation or β-arrestin scaffolding, is required for epidermal growth factor receptor transactivation and cardiomyocyte hypertrophy via the angiotensin type 1 receptor.
Increased Circulating FGF23 Does Not Lead to Cardiac Hypertrophy in the Male Hyp Mouse Model of XLH.
Liu, Eva S; Thoonen, Robrecht; Petit, Elizabeth; Yu, Binglan; Buys, Emmanuel S; Scherrer-Crosbie, Marielle; Demay, Marie B
2018-05-01
Serum levels of fibroblast growth factor 23 (FGF23) markedly increase with renal impairment, with FGF23 levels correlating with the presence of left ventricular hypertrophy (LVH) and mortality in patients with chronic kidney disease (CKD). FGF23 activates calcineurin/nuclear factor of activated T cell (NFAT) signaling and induces hypertrophy in murine cardiomyocytes. X-linked hypophosphatemia (XLH) is characterized by high circulating levels of FGF23 but, in contrast to CKD, is associated with hypophosphatemia. The cardiac effects of high circulating levels of FGF23 in XLH are not well defined. Thus, studies were undertaken to define the cardiac phenotype in the mouse model of XLH (Hyp mice). Echocardiographic and histological analyses demonstrated that Hyp left ventricles (LVs) are smaller than those of wild-type mice. Messenger RNA expression of cardiac hypertrophy markers was not altered in the LV or right ventricle of Hyp mice. However, the Hyp LVs had increased expression of the NFAT target genes NFATc1 and RCAN1. To determine whether phosphate alone can induce markers of hypertrophy, differentiated C2C12 myocytes were treated with phosphate. Phosphate treatment increased expression of cardiac hypertrophy markers, supporting a primary role for phosphate in inducing LVH. Although previous studies showed that increased circulating FGF23 and phosphate levels are associated with LVH, our results demonstrated that in XLH, high circulating levels of FGF23 in the setting of hypophosphatemia do not induce cardiac hypertrophy.
Pieruzzi, Federico; Pieroni, Maurizio; Zachara, Elisabetta; Marziliano, Nicola; Morrone, Amelia; Cecchi, Franco
2015-11-01
Anderson-Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations of the GLA gene that encodes alpha-galactosidase A. It is characterized by a multisystemic involvement: the renal, neurological, heart, cochleovestibular and cutaneous systems are the most damaged. Morbidity and mortality of Anderson-Fabry disease depend on renal insufficiency, heart failure and nervous system involvement. Left ventricular hypertrophy is the most common cardiac manifestation followed by conduction system disease, valve dysfunction, and arrhythmias. Mild to moderate left ventricular hypertrophy may simulate a non-obstructive hypertrophic cardiomyopathy. Management of Anderson-Fabry disease starting from the diagnosis of cardiac involvement, the prevention of complications, the therapeutic aspects, up to appropriate clinical follow-up, requires a multidisciplinary approach. According to recent management guidelines, only few evidence-based data are available to guide the clinical and therapeutic approach to this rare disease. An Italian Board, composed by nephrologists, cardiologists, geneticists, pediatricians and neurologists has been established in order to approve by consensus a diagnostic and therapeutic management protocol. The authors report the results of this cardiologic management consensus.
Domienik-Karłowicz, Justyna; Rymarczyk, Zuzanna; Lisik, Wojciech; Kurnicka, Katarzyna; Ciurzyński, Michał; Bielecki, Maksymilian; Kosieradzki, Maciej; Pruszczyk, Piotr
2018-06-17
Current diagnostic ECG criteria of left ventricular hypertrophy in obese patients are still lacking. To assess the current ECG diagnostic criteria of LVH, and to validate our previously proposed criteria in a group of patients with morbid obesity. A group of consecutive 429 obese patients (MOP) with BMI of at least 35 kg/m 2 (mean age 38.6 ± 8.9 years, BMI 48.7 ± 9.0 kg/m 2 ; 323 females, 106 males) were included. The diagnosis of LVH in MOPs was confirmed only by RaVL of 7.5 mm, Cornell index of 12.5 mm; Cornell index × QRS duration of 1,125 mm × ms and Romhilt-Estes score of 1. None of the criteria proposed to date is appropriate in super-morbidly obese patients. Our study confirmed that none of the currently used voltage-based ECG criteria is appropriate for diagnosing LVH in morbidly obese patients. Further studies are required. © 2018 Wiley Periodicals, Inc.
Tarikuz Zaman, A K M; McLean, Danielle L; Sobel, Burton E
2013-10-01
Angiotensin II receptor blockers (ARBs) are used widely for the treatment of heart failure. However, their use in obese and insulin-resistant patients remains controversial. To clarify their potential efficacy in these conditions, we administered azilsartan medoxomil (azilsartan), a prodrug of an angiotensin II receptor blocker to mice fed a high-fat diet (HFD) with left ventricular (LV) pressure overload (aortic banding). LV fibrosis (hydroxyproline), cardiac plasminogen activator inhibitor-1 (PAI-1; a marker of profibrosis), and creatine kinase (a marker of myocardial viability and energetics) were assessed. LV wall thickness and cardiac function were assessed echocardiographically. Mice given a HFD were obese and insulin resistant. Their LV hypertrophy was accompanied by greater LV PAI-1 and reduced LV creatine kinase compared with normal diet controls. Drug treatment reduced LV wall thickness, hypertrophy, and PAI-1 and increased cardiac output after aortic banding compared with results in HFD vehicle controls. Thus, azilsartan exerted favorable biological effects on the hearts of obese insulin-resistant mice subjected to LV pressure overload consistent with its potential utility in patients with analogous conditions.
Beer, Meinrad; Weidemann, Frank; Breunig, Frank; Knoll, Anita; Koeppe, Sabrina; Machann, Wolfram; Hahn, Dietbert; Wanner, Christoph; Strotmann, Jörg; Sandstede, Jörn
2006-05-15
The present study evaluated the evolution of cardiac morphology, function, and late enhancement as a noninvasive marker of myocardial fibrosis, and their inter-relation during enzyme replacement therapy in patients with Fabry's disease using magnetic resonance imaging and color Doppler myocardial imaging. Late enhancement, which was present in up to 50% of patients, was associated with increased left ventricular mass, the failure of a significant regression of hypertrophy during enzyme replacement therapy, and worse segmental myocardial function. Late enhancement may predict the effect of enzyme replacement therapy on left ventricular mass and cardiac function.
Slay, Christopher E; Enok, Sanne; Hicks, James W; Wang, Tobias
2014-05-15
Physiological cardiac hypertrophy is characterized by reversible enlargement of cardiomyocytes and changes in chamber architecture, which increase stroke volume and via augmented convective oxygen transport. Cardiac hypertrophy is known to occur in response to repeated elevations of O2 demand and/or reduced O2 supply in several species of vertebrate ectotherms, including postprandial Burmese pythons (Python bivittatus). Recent data suggest postprandial cardiac hypertrophy in P. bivittatus is a facultative rather than obligatory response to digestion, though the triggers of this response are unknown. Here, we hypothesized that an O2 supply-demand mismatch stimulates postprandial cardiac enlargement in Burmese pythons. To test this hypothesis, we rendered animals anemic prior to feeding, essentially halving blood oxygen content during the postprandial period. Fed anemic animals had heart rates 126% higher than those of fasted controls, which, coupled with a 71% increase in mean arterial pressure, suggests fed anemic animals were experiencing significantly elevated cardiac work. We found significant cardiac hypertrophy in fed anemic animals, which exhibited ventricles 39% larger than those of fasted controls and 28% larger than in fed controls. These findings support our hypothesis that those animals with a greater magnitude of O2 supply-demand mismatch exhibit the largest hearts. The 'low O2 signal' stimulating postprandial cardiac hypertrophy is likely mediated by elevated ventricular wall stress associated with postprandial hemodynamics. © 2014. Published by The Company of Biologists Ltd.
Cardiac considerations in the triathlete.
Douglas, P S
1989-10-01
The cardiac adaptation to exercise training produces a variety of adaptations in cardiac size, shape, and function. To further define these changes and to investigate the effects of maximal conditioning, we studied ultraendurance triathletes training for the Hawaii Ironman Triathlon using echocardiography, Doppler ultrasound, and electrocardiography. In this population, the left ventricle (LV) was of normal size but had increased wall thickness and mass. Systolic function was normal and diastolic function was normal or supernormal (increased ratio of rapid to atrial LV filling velocities). The finding of a pattern of concentric hypertrophy was reinforced by a close relationship between submaximal exercise systolic blood pressure and LV mass (r = 0.88). Examination of valvular function by Doppler ultrasound revealed significantly increased prevalences of mitral and tricuspid regurgitation in athletes, with 91% of athletes (vs 38% of controls) having regurgitation detected in at least one cardiac valve. Analysis of athletes using standard electrocardiographic criteria for the detection of left ventricular hypertrophy showed that these criteria did not reliably detect increased mass. However, changes such as marked QRS prolongation and nonvoltage criteria for LV hypertrophy and RV hypertrophy may be useful in separating physiologic from pathologic hypertrophy. Our studies provide additional descriptions of cardiac changes produced by ultraendurance exercise training and suggest that the hemodynamic load imposed by exercise may be a contributing cause to physiologic hypertrophy. Much yet remains to be learned about the cardiac adaptation to exercise training.
Zhang, Lianghui; Malik, Sundeep; Kelley, Grant G.; Kapiloff, Michael S.; Smrcka, Alan V.
2011-01-01
To define a role for phospholipase Cϵ (PLCϵ) signaling in cardiac myocyte hypertrophic growth, PLCϵ protein was depleted from neonatal rat ventricular myocytes (NRVMs) using siRNA. NRVMs with PLCϵ depletion were stimulated with endothelin (ET-1), norepinephrine, insulin-like growth factor-1 (IGF-1), or isoproterenol and assessed for development of hypertrophy. PLCϵ depletion dramatically reduced hypertrophic growth and gene expression induced by all agonists tested. PLCϵ catalytic activity was required for hypertrophy development, yet PLCϵ depletion did not reduce global agonist-stimulated inositol phosphate production, suggesting a requirement for localized PLC activity. PLCϵ was found to be scaffolded to a muscle-specific A kinase anchoring protein (mAKAPβ) in heart and NRVMs, and mAKAPβ localizes to the nuclear envelope in NRVMs. PLCϵ-mAKAP interaction domains were defined and overexpressed to disrupt endogenous mAKAPβ-PLCϵ complexes in NRVMs, resulting in significantly reduced ET-1-dependent NRVM hypertrophy. We propose that PLCϵ integrates multiple upstream signaling pathways to generate local signals at the nucleus that regulate hypertrophy. PMID:21550986
Devlin, A M; Brosnan, M J; Graham, D; Morton, J J; McPhaden, A R; McIntyre, M; Hamilton, C A; Reid, J L; Dominiczak, A F
1998-01-01
To assess the vascular and cardiac response to NO (nitric oxide) synthase (NOS) blockade in vivo, Wistar-Kyoto rats (WKY) were treated for 3 wk with NG-nitro-L-arginine methyl ester (L-NAME; 10 mg.kg-1.day-1). L-NAME treatment induced hypertension that was associated with increased plasma renin activity. Flow cytometry cell cycle DNA analysis showed that aortic vascular smooth muscle cells (VSMC) from L-NAME-treated WKY had a significantly higher polyploid population compared with WKY controls. Using organ bath experiments, we have shown that aortic rings from L-NAME-treated WKY have an increased contractile response to phenylephrine and impaired relaxation to carbachol compared with control rings. NOS blockade in vivo caused a significant increase in cardiac and left ventricular hypertrophy. Northern mRNA analysis of the myocardium showed that L-NAME treatment caused reexpression of the fetal skeletal alpha-actin isoform without alterations in collagen type I expression, a pattern indicating true hypertrophy of the cardiomyocytes. These studies provide further insight to confirm that NO deficiency in vivo results in the development of vascular and cardiac hypertrophy.
Slavic, Svetlana; Ford, Kristopher; Modert, Magalie; Becirovic, Amarela; Handschuh, Stephan; Baierl, Andreas; Katica, Nejla; Zeitz, Ute; Erben, Reinhold G; Andrukhova, Olena
2017-09-12
Left ventricular hypertrophy (LVH) ultimately leads to heart failure in conditions of increased cardiac pre- or afterload. The bone-derived phosphaturic and sodium-conserving hormone fibroblast growth factor-23 (FGF23) and its co-receptor Klotho have been implicated in the development of uremic LVH. Using transverse aortic constriction (TAC) in gene-targeted mouse models, we examine the role of Fgf23 and Klotho in cardiac hypertrophy and dysfunction induced by pressure overload. TAC profoundly increases serum intact Fgf23 due to increased cardiac and bony Fgf23 transcription and downregulation of Fgf23 cleavage. Aldosterone receptor blocker spironolactone normalizes serum intact Fgf23 levels after TAC by reducing bony Fgf23 transcription. Notably, genetic Fgf23 or Klotho deficiency does not influence TAC-induced hypertrophic remodelling, LV functional impairment, or LV fibrosis. Despite the profound, aldosterone-mediated increase in circulating intact Fgf23 after TAC, our data do not support an essential role of Fgf23 or Klotho in the pathophysiology of pressure overload-induced cardiac hypertrophy.
Agarwal, Rajiv
2017-02-03
Cardiovascular morbidity and mortality was reduced by 25% when blood pressure (BP) was targeted to 120 mm Hg systolic compared with 140 mm Hg systolic in Systolic Blood Pressure Intervention Trial (SPRINT); however, BP was measured using a research technique. SPRINT specified 5 minutes of seated rest in a quiet room followed by 3 oscillometric measurements without an observer in the room. The relationship of this research-grade methodology to routine BP measurements is not known. Among 275 people with chronic kidney disease who had BP <140/90 mm Hg when they came to the clinic, we measured BP as in SPRINT and recorded BP on the same day without specification of seated rest. Compared with routine measurement, the research-grade systolic BP was 12.7 mm Hg lower with wide limits of agreement (-46.1 to 20.7 mm Hg). Research grade systolic BP was 7.9 mm Hg lower than daytime ambulatory systolic BP and had wide agreement limits (-33.2 to 17.4 mm Hg). Whereas the routine, research-grade, and daytime ambulatory systolic BP were all related to echocardiographic left ventricular hypertrophy, the strength of the relationship between research-grade and daytime ambulatory systolic BP to left ventricular hypertrophy was similar and stronger than the strength of the relationship between routine systolic BP and left ventricular hypertrophy. Taken together, these results suggest that translation of the SPRINT results will require measurement of BP as performed in that trial. Instead of an algebraic manipulation of routine clinic measurements, the SPRINT methodology of BP measurement would be needed at minimum if implementation of the SPRINT results were to be deployed in the population at large. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
N-acetylcysteine improves established monocrotaline-induced pulmonary hypertension in rats
2014-01-01
Background The outcome of patients suffering from pulmonary arterial hypertension (PAH) are predominantly determined by the response of the right ventricle to the increase afterload secondary to high vascular pulmonary resistance. However, little is known about the effects of the current available or experimental PAH treatments on the heart. Recently, inflammation has been implicated in the pathophysiology of PAH. N-acetylcysteine (NAC), a well-known safe anti-oxidant drug, has immuno-modulatory and cardioprotective properties. We therefore hypothesized that NAC could reduce the severity of pulmonary hypertension (PH) in rats exposed to monocrotaline (MCT), lowering inflammation and preserving pulmonary vascular system and right heart function. Methods Saline-treated control, MCT-exposed, MCT-exposed and NAC treated rats (day 14–28) were evaluated at day 28 following MCT for hemodynamic parameters (right ventricular systolic pressure, mean pulmonary arterial pressure and cardiac output), right ventricular hypertrophy, pulmonary vascular morphometry, lung inflammatory cells immunohistochemistry (monocyte/macrophages and dendritic cells), IL-6 expression, cardiomyocyte hypertrophy and cardiac fibrosis. Results The treatment with NAC significantly decreased pulmonary vascular remodeling, lung inflammation, and improved total pulmonary resistance (from 0.71 ± 0.05 for MCT group to 0.50 ± 0.06 for MCT + NAC group, p < 0.05). Right ventricular function was also improved with NAC treatment associated with a significant decrease in cardiomyocyte hypertrophy (625 ± 69 vs. 439 ± 21 μm2 for MCT and MCT + NAC group respectively, p < 0.001) and heart fibrosis (14.1 ± 0.8 vs. 8.8 ± 0.1% for MCT and MCT + NAC group respectively, p < 0.001). Conclusions Through its immuno-modulatory and cardioprotective properties, NAC has beneficial effect on pulmonary vascular and right heart function in experimental PH. PMID:24929652
Moroni, C; Tolone, S; Lopreiato, F; Scrofani, A R; Bossini, A; Affricano, C; Cassone, R; Gaudio, C
2017-03-01
Reversal of left ventricular hypertrophy (LVH) in hypertensive patients appears to be a desirable goal to the reduction cardiac risk. The Renin-Angiotensin System (RAS) seems to play a major role in the establishment and maintenance of LVH through the activated systemic RAS and the Intracardiac Angiotensin System (IAS). We focused on the effects of a three-year treatment with losartan supplement in hypertensive patients with LVH not responding to eight years of an effective previous antihypertensive pharmacological treatment. Two groups of 28 sex-, age- and therapy-matched subjects with essential hypertension and LVH were taken into consideration. The two groups were in effective pharmacological treatment (BP < 140/90) for eight years previous to their enrollment. Patients of Group A were treated for three years with a losartan (100 mg/die) on-top treatment, whereas patients of Group B continued the follow-up of the previous conventional therapy. Both groups were submitted to an echocardiographic follow-up. Group A, showed a significant reduction of the mean LVH since the first step at six months with a further significant trend during the whole period (variance analysis: p < 0.001). Group B showed a non-significant trend toward LVH reduction during the three-year follow-up. No significant further reduction of systolic or diastolic blood pressure values was observed in both groups. The effects of losartan in hypertensive and hypertrophic patients are in agreement with the results of LIFE Trial. However, the reduction of left ventricular hypertrophy in our patients seems to be related to changes inducted by losartan on the IAS, since no further hemodynamic effects were observed. Losartan induced both a significant reduction of LVH and an improvement of LV diastolic function with a subsequent expected beneficial shift on the prognosis.
[Understanding heart failure].
Boo, José Fernando Guadalajara
2006-01-01
Heart failure is a disease with several definitions. The term "heart failure" is used by has brougth about confusion in the terminology. For this reason, the value of the ejection fraction (< 0.40 or < 0.35) is used in most meganalyses on the treatment of heart failure, avoiding the term "heart failure" that is a confounding concept. In this paper we carefully analyze the meaning of contractility, ventricular function or performance, preload, afterload, heart failure, compensation mechanisms in heart failure, myocardial oxygen consumption, inadequate, adequate and inappropriate hypertrophy, systole, diastole, compliance, problems of relaxation, and diastolic dysfunction. Their definitions are supported by the original scientific descriptions in an attempt to clarify the concepts about ventricular function and heart failure and, in this way, use the same scientific language about the meaning of ventricular function, heart failure, and diastolic dysfunction.
NASA Astrophysics Data System (ADS)
Ulerich, J.; Göktepe, S.; Kuhl, E.
This manuscript presents a continuum approach towards cardiac growth and remodeling that is capable to predict chronic maladaptation of the heart in response to changes in mechanical loading. It is based on the multiplicative decomposition of the deformation gradient into and elastic and a growth part. Motivated by morphological changes in cardiomyocyte geometry, we introduce an anisotropic growth tensor that can capture both hypertrophic wall thickening and ventricular dilation within one generic concept. In agreement with clinical observations, we propose wall thickening to be a stress-driven phenomenon whereas dilation is introduced as a strain-driven process. The features of the proposed approach are illustrated in terms of the adaptation of thin heart slices and in terms overload-induced dilation in a generic bi-ventricular heart model.
Pérez-Lahiguera, Francisco J; Rodilla, Enrique; Costa, Jose A; Gonzalez, Carmen; Martín, Joaquin; Pascual, Jose M
2012-12-01
The purpose of the present study was to assess the relationship of central and peripheral blood pressure to left ventricular mass. Cross-sectional study that included 392 never treated hypertensive individuals. Measurement of office, 24-h ambulatory, and central blood pressure (obtained using applanation tonometry) and determination of left ventricular mass by echocardiography were performed in all patients. In a multiple regression analysis, with adjustment for age, gender and metabolic syndrome, 24-h blood pressure was more closely related to ventricular mass than the respective office and central blood pressures. Systolic blood pressures always exhibited a higher correlation than diastolic blood pressures in all 3 determinations. The correlation between left ventricular mass index and 24-h systolic blood pressure was higher than that of office (P<.002) or central systolic blood pressures (P<.002). Changes in 24-h systolic blood pressure caused the greatest variations in left ventricular mass index (P<.001). In our population of untreated middle-aged hypertensive patients, left ventricular mass index is more closely related to 24-h ambulatory blood pressure than to office or central blood pressure. Central blood pressure does not enable us to better identify patients with left ventricular hypertrophy. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.
Li, K; Qiao, J; Zhao, L; Dong, S; Ou, D; Wang, J; Wang, H; Xu, T
2006-11-01
Right ventricular hypertrophy and failure is an important step in the development of ascites syndrome (AS) in broiler chickens. Cytoplasmic calcium concentration is a major regulator of cardiac contractile function and various physiological processes in cardiac muscle cells. The purpose of this study was to measure the right ventricular pressure and investigate the precise ultrastructural location of Ca(2+) and Ca(2+)-ATPase in the right ventricular myocardium of chickens with AS induced by low ambient temperature. The results showed that the right ventricular diastolic pressure of ascitic broilers was significantly higher than that of control broilers (P < 0.01), and the maximum change ratio of right intraventricular pressure (RV +/- dp/dt(max)) of ascitic broilers was significantly lower than that of the controls (P < 0.01). Extensively increased calcium deposits were observed in the right ventricular myocardium of ascitic broilers, whereas in the age-matched control broilers, calcium deposits were much less. The Ca(2+)-ATPase reactive products were obviously found on the sarcoplasmic reticulum and mitochondrial membrane of the control right ventricular myocardium, but rarely observed in the ascitic broilers. The data suggest that in ascitic broilers there is the right ventricular diastolic dysfunction, in which the overload of intracellular calcium and the decreased Ca(2+)-ATPase activity might be the important factors.
Iacopo, Fabiani; Lorenzo, Conte; Calogero, Enrico; Matteo, Passiatore; Riccardo, Pugliese Nicola; Veronica, Santini; Valentina, Barletta; Riccardo, Liga; Cristian, Scatena; Maria, Mazzanti Chiara; Vitantonio, Di Bello
2016-01-01
MicroRNAs (miRNAs) are a huge class of noncoding RNAs that regulate protein-encoding genes (degradation/inhibition of translation). miRNAs are nowadays recognized as regulators of biological processes underneath cardiovascular disorders including hypertrophy, ischemia, arrhythmias, and valvular disease. In particular, circulating miRNAs are promising biomarkers of pathology. This review gives an overview of studies in aortic valve stenosis (AS), exclusively considering myocardial remodeling processes. We searched through literature (till September 2016), all studies and reviews involving miRNAs and AS (myocardial compartment). Although at the beginning of a new era, clear evidences exist on the potential diagnostic and prognostic implementation of miRNAs in the clinical setting. In particular, for AS, miRNAs are modulators of myocardial remodeling and hypertrophy. In our experience, here presented in summary, the principal findings of our research were a confirm of the pathophysiological role in AS of miRNA-21, in particular, the interdependence between textural miRNA-21 and fibrogenic stimulus induced by an abnormal left ventricular pressure overload. Moreover, circulating miRNA-21 (biomarker) levels are able to reflect the presence of significant myocardial fibrosis (MF). Thus, the combined evaluation of miRNA-21, a marker of MF, and hypertrophy, together with advanced echocardiographic imaging (two-dimensional speckle tracking), could fulfill many existing gaps, renewing older guidelines paradigms, also allowing a better risk prognostic and diagnostic strategies.
Effect of Sex and Sporting Discipline on LV Adaptation to Exercise.
Finocchiaro, Gherardo; Dhutia, Harshil; D'Silva, Andrew; Malhotra, Aneil; Steriotis, Alexandros; Millar, Lynne; Prakash, Keerthi; Narain, Rajay; Papadakis, Michael; Sharma, Rajan; Sharma, Sanjay
2017-09-01
This study sought to investigate the effect of different types of exercise on left ventricular (LV) geometry in a large group of female and male athletes. Studies assessing cardiac adaptation in female and male athletes indicate that female athletes reveal smaller increases in LV wall thickness and cavity size compared with male athletes. However, data on sex-specific changes in LV geometry in athletes are scarce. A total of 1,083 healthy, elite, white athletes (41% female; mean age 21.8 ± 5.7 years) assessed with electrocardiogram and echocardiogram were considered. LV geometry was classified into 4 groups according to relative wall thickness (RWT) and left ventricular mass (LVM) as per European and American Society of Echocardiography guidelines: normal (normal LVM/normal RWT), concentric hypertrophy (increased LVM/increased RWT), eccentric hypertrophy (increased LVM/normal RWT), and concentric remodeling (normal LVM/increased RWT). Athletes were engaged in 40 different sporting disciplines with similar participation rates with respect to the type of exercise between females and males. Females exhibited lower LVM (83 ± 17 g/m 2 vs. 101 ± 21 g/m 2 ; p < 0.001) and RWT (0.35 ± 0.05 vs. 0.36 ± 0.05; p < 0.001) compared with male athletes. Females also demonstrated lower absolute LV dimensions (49 ± 4 mm vs. 54 ± 5 mm; p < 0.001) but following correction for body surface area, the indexed LV dimensions were greater in females (28.6 ± 2.7 mm/m 2 vs. 27.2 ± 2.7 mm/m 2 ; p < 0.001). Most athletes showed normal LV geometry. A greater proportion of females competing in dynamic sport exhibited eccentric hypertrophy compared with males (22% vs. 14%; p < 0.001). In this subgroup only 4% of females compared with 15% of males demonstrated concentric hypertrophy/remodeling (p < 0.001). Highly trained athletes generally show normal LV geometry; however, female athletes participating in dynamic sport often exhibit eccentric hypertrophy. Although concentric remodeling or hypertrophy in male athletes engaged in dynamic sport is relatively common, it is rare in female athletes and may be a marker of disease in a symptomatic athlete. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Ernst, Michael E.; Neaton, James D.; Grimm, Richard H.; Collins, Gary; Thomas, William; Soliman, Elsayed Z.; Prineas, Ronald J.
2011-01-01
Chlorthalidone (CTD) reduces 24-hour blood pressure more effectively than hydrochlorothiazide (HCTZ), but whether this influences electrocardiographic left ventricular hypertrophy (LVH) is uncertain. One source of comparative data is the Multiple Risk Factor Intervention Trial (MRFIT), which randomly assigned 8,012 hypertensive men to special intervention (SI) or usual care (UC). SI participants could use CTD or HCTZ initially; previous analyses have grouped clinics by their main diuretic used (C-clinics: CTD; H-clinics: HCTZ). After 48 months, SI participants receiving HCTZ were recommended to switch to CTD, in part, because higher mortality was observed for SI compared to UC participants in H-clinics, while the opposite was found in C-clinics. In this analysis, we examined change in continuous measures of electrocardiographic LVH using both an ecologic analysis by previously-reported C- or H-clinic groupings, and an individual participant analysis where use of CTD or HCTZ by SI participants was considered and updated annually. Through 48 months, differences between SI and UC in LVH were larger for C-clinics compared to H-clinics (Sokolow-Lyon: −93.9 vs −54.9 μV, P=0.049; Cornell voltage: −68.1 vs −35.9 μV, P=0.019; Cornell voltage product: −4.6 vs −2.2 μV/ms, P=0.071; left ventricular mass: −4.4 vs −2.8 gm, P=0.002). At the individual participant level, Sokolow-Lyon and left ventricular mass were significantly lower for SI men receiving CTD compared to HCTZ through 48 months and 84 months of follow-up. Our findings on LVH support the idea that greater blood pressure reduction with CTD than HCTZ may have led to differences in mortality observed in MRFIT. PMID:22025372
Imai, Yousuke; Kariya, Taro; Iwakiri, Masaki; Yamada, Yoshitsugu; Takimoto, Eiki
2018-01-01
Right ventricular (RV) dysfunction following left ventricular (LV) failure is associated with poor prognosis. RV remodeling is thought initiated by the increase in the afterload of RV due to secondary pulmonary hypertension (PH) to impaired LV function; however, RV molecular changes might occur in earlier stages of the disease. cGMP (cyclic guanosine monophosphate)-phosphodiesterase 5 (PDE5) inhibitors, widely used to treat PH through their pulmonary vasorelaxation properties, have shown direct cardiac benefits, but their impacts on the RV in LV diseases are not fully determined. Here we show that RV molecular alterations occur early in the absence of RV hemodynamic changes during LV pressure-overload and are ameliorated by PDE5 inhibition. Two-day moderate LV pressure-overload (transverse aortic constriction) neither altered RV pressure/ function nor RV weight in mice, while it induced only mild LV hypertrophy. Importantly, pathological molecular features were already induced in the RV free wall myocardium, including up-regulation of gene markers for hypertrophy and inflammation, and activation of extracellular signal-regulated kinase (ERK) and calcineurin. Concomitant PDE5 inhibition (sildenafil) prevented induction of such pathological genes and activation of ERK and calcineurin in the RV as well as in the LV. Importantly, dexamethasone also prevented these RV molecular changes, similarly to sildenafil treatment. These results suggest the contributory role of inflammation to the early pathological interventricular interaction between RV and LV. The current study provides the first evidence for the novel early molecular cross-talk between RV and LV, preceding RV hemodynamic changes in LV disease, and supports the therapeutic strategy of enhancing cGMP signaling pathway to treat heart diseases.
Changes in Left Ventricular Morphology and Function After Mitral Valve Surgery
Shafii, Alexis E.; Gillinov, A. Marc; Mihaljevic, Tomislav; Stewart, William; Batizy, Lillian H.; Blackstone, Eugene H.
2015-01-01
Degenerative mitral valve disease is the leading cause of mitral regurgitation in North America. Surgical intervention has hinged on symptoms and ventricular changes that develop as compensatory ventricular remodeling takes place. In this study, we sought to characterize the temporal response of left ventricular (LV) morphology and function to mitral valve surgery for degenerative disease, and identify preoperative factors that influence reverse remodeling. From 1986–2007, 2,778 patients with isolated degenerative mitral valve disease underwent valve repair (n=2,607/94%) or replacement (n=171/6%) and had at least 1 postoperative transthoracic echocardiogram (TTE); 5,336 TTEs were available for analysis. Multivariable longitudinal repeated-measures analysis was performed to identify factors associated with reverse remodeling. LV dimensions decreased in the first year after surgery (end-diastolic from 5.7±0.80 to 4.9±1.4 cm; end-systolic from 3.4±0.71 to 3.1±1.4 cm). LV mass index decreased from 139±44 to 112±73 g·m−2. Reduction of LV hypertrophy was less pronounced in patients with greater preoperative left heart enlargement (P<.0001) and greater preoperative LV mass (P<.0001). Postoperative LV ejection fraction initially decreased from 58±7.0 to 53±20, increased slightly over the first postoperative year, and was negatively influenced by preoperative heart failure symptoms (P<.0001) and lower preoperative LV ejection fraction (P<.0001). Risk-adjusted response of LV morphology and function to valve repair and replacement was similar (P>.2). In conclusion, a positive response toward normalization of LV morphology and function after mitral valve surgery is greatest in the first year. The best response occurs when surgery is performed before left heart dilatation, LV hypertrophy, or LV dysfunction develop. PMID:22534055
Paulis, Ludovit; Pechanova, Olga; Zicha, Josef; Krajcirovicova, Kristina; Barta, Andrej; Pelouch, Vaclav; Adamcova, Michaela; Simko, Fedor
2009-08-01
Melatonin was shown to reduce blood pressure, enhance nitric oxide availability and scavenge free radicals. There is, however, a shortage of data with respect to the effect of melatonin on pathological left ventricular remodelling associated with haemodynamic overload. We investigated whether melatonin was able to prevent left ventricular hypertrophy (LVH) and fibrosis associated with N(G)-nitro-L-arginine-methyl ester (L-NAME)-induced hypertension. Four groups of male Wistar rats were investigated: control, L-NAME (50 mg/kg per day), melatonin (10 mg/kg per day) and L-NAME plus melatonin. Blood pressure was measured non-invasively each week. After 5 weeks of treatment the animals were killed and nitric oxide synthase (NOS) activity, endothelial and inducible NOS expression, the level of collagenous proteins, hydroxyproline and conjugated dienes in the left ventricle were determined. The administration of L-NAME inhibited NOS activity, increased conjugated dienes concentration, elevated blood pressure and induced LVH and fibrosis (indicated by increased collagenous proteins and hydroxyproline levels). The addition of melatonin to L-NAME treatment failed to prevent the attenuation of NOS activity and the development of LVH and prevented hypertension only partly. The administration of melatonin, however, completely prevented the increase in conjugated dienes concentration and the development of left ventricular fibrosis. NOS expression was not different among experimental groups. Melatonin prevented the development of left ventricular fibrosis and the increase in oxidative load in rats with L-NAME-induced hypertension. The antifibrotic effect of melatonin seems to be independent of its effects on NOS activity and might be linked to its antioxidant properties.
Abdollahi, Farzane; Joukar, Siyavash; Najafipour, Hamid; Karimi, Abdolah; Masumi, Yaser; Binayi, Fateme
2016-01-01
Anabolic steroids used to improve muscular strength and performance in athletics. Its long-term consumption may induce cardiovascular adverse effects. We assessed the risk of ventricular arrhythmias in rats which subjected to chronic nandrolone plus high-intensity endurance exercise. Animals were grouped as; control (CTL), exercise (Ex): 8 weeks under exercise, vehicle group (Arach): received arachis oil, and Nan group: received nandrolone decanoate 5 mg/kg twice a week for 8 weeks, Arach+Ex group, and Nan+Ex. Finally, under anesthesia, arrhythmia was induced by infusion of 1.5 μg/0.1 mL/min of aconitine IV and ventricular arrhythmias were recorded for 15 min. Then, animals' hearts were excised and tissue samples were taken. Nandrolone plus exercise had no significant effect on blood pressure but decreased the heart rate (P<0.01) and increased the RR (P<0.01) and JT intervals (P<0.05) of electrocardiogram. Nandrolone+exercise significantly increased the ventricular fibrillation (VF) frequency and also decreased the VF latency (P<0.05 versus CTL group). Combination of exercise and nandrolone could not recover the decreasing effects of nandrolone on animals weight gain but, it enhanced the heart hypertrophy index (P<0.05). In addition, nandrolone increased the level of hydroxyproline (HYP) and malondialdehyde (MDA) but had not significant effect on glutathione peroxidase of heart. Exercise only prevented the effect of nandrolone on HYP. Nandrolone plus severe exercise increases the risk of VF that cannot be explained only by the changes in redox system. The intensification of cardiac hypertrophy and prolongation of JT interval may be a part of involved mechanisms. Copyright © 2015 Elsevier Inc. All rights reserved.
miR-139-5p inhibits isoproterenol-induced cardiac hypertrophy by targetting c-Jun.
Ming, Su; Shui-Yun, Wang; Wei, Qiu; Jian-Hui, Li; Ru-Tai, Hui; Lei, Song; Mei, Jia; Hui, Wang; Ji-Zheng, Wang
2018-04-27
Hypertrophic cardiomyopathy (HCM) is a serious monogenic disease characterized by cardiac hypertrophy, fibrosis, sudden cardiac death, and heart failure. Previously, we identified that miR-139-5p was down-regulated in HCM patients. However, the regulatory effects of miR-139-5p remain unclear. Thus, we investigated the role of miR-139-5p in the regulation of cardiac hypertrophy. The expression of miR-139-5p in left ventricular tissues in HCM patients and mice subjected to transverse aortic constriction (TAC) was significantly down-regulated. Knockdown of miR-139-5p expression in neonatal rat cardiomyocytes (NRCMs) induced cardiomyocyte enlargement and increased atrial natriuretic polypeptide (ANP) expression. Overexpression of miR-139-5p antagonized isoproterenol (ISO)-induced cardiomyocyte enlargement and ANP/brain natriuretic peptide (BNP) up-regulation. More importantly, we found that c-Jun expression was inhibited by miR-139-5p in NRCMs. Knockdown of c-Jun expression significantly attenuated cardiac hypertrophy induced by miR-139-5p deprivation. Our data indicated that miR-139-5p was down-regulated in the hearts of HCM patients and that it inhibited cardiac hypertrophy by targetting c-Jun expression. © 2018 The Author(s).
Kumar, Santosh; Wang, Gang; Liu, Wenjuan; Ding, Wenwen; Dong, Ming; Zheng, Na; Ye, Hongyu; Liu, Jie
2018-06-11
HIMF (hypoxia-induced mitogenic factor/found in inflammatory zone 1/resistin like α) is a secretory and cytokine-like protein and serves as a critical stimulator of hypoxia-induced pulmonary hypertension. With a role for HIMF in heart disease unknown, we explored the possible roles for HIMF in cardiac hypertrophy by overexpressing and knocking down HIMF in cardiomyocytes and characterizing HIMF gene ( himf ) knockout mice. We found that HIMF mRNA and protein levels were upregulated in phenylephrine-stimulated cardiomyocyte hypertrophy and our mouse model of transverse aortic constriction-induced cardiac hypertrophy, as well as in human hearts with dilated cardiomyopathy. Furthermore, HIMF overexpression could induce cardiomyocyte hypertrophy, as characterized by elevated protein expression of hypertrophic biomarkers (ANP [atrial natriuretic peptide] and β-MHC [myosin heavy chain-β]) and increased cell-surface area compared with controls. Conversely, HIMF knockdown prevented phenylephrine-induced cardiomyocyte hypertrophy and himf ablation in knockout mice significantly attenuated transverse aortic constriction-induced hypertrophic remodeling and cardiac dysfunction. HIMF overexpression increased the cytosolic Ca 2+ concentration and activated the CaN-NFAT (calcineurin-nuclear factor of activated T cell) and MAPK (mitogen-activated protein kinase) pathways; this effect could be prevented by reducing cytosolic Ca 2+ concentration with L-type Ca 2+ channel blocker nifedipine or inhibiting the CaSR (Ca 2+ sensing receptor) with Calhex 231. Furthermore, HIMF overexpression increased HIF-1α (hypoxia-inducible factor) expression in neonatal rat ventricular myocytes, and HIMF knockout inhibited HIF-1α upregulation in transverse aortic constriction mice. Knockdown of HIF-1α attenuated HIMF-induced cardiomyocyte hypertrophy. In conclusion, HIMF has a critical role in the development of cardiac hypertrophy, and targeting HIMF may represent a potential therapeutic strategy. © 2018 American Heart Association, Inc.
Cytoskeletal mechanics in pressure-overload cardiac hypertrophy
NASA Technical Reports Server (NTRS)
Tagawa, H.; Wang, N.; Narishige, T.; Ingber, D. E.; Zile, M. R.; Cooper, G. 4th
1997-01-01
We have shown that the cellular contractile dysfunction characteristic of pressure-overload cardiac hypertrophy results not from an abnormality intrinsic to the myofilament portion of the cardiocyte cytoskeleton but rather from an increased density of the microtubule component of the extramyofilament portion of the cardiocyte cytoskeleton. To determine how, in physical terms, this increased microtubule density mechanically overloads the contractile apparatus at the cellular level, we measured cytoskeletal stiffness and apparent viscosity in isolated cardiocytes via magnetic twisting cytometry, a technique by which magnetically induced force is applied directly to the cytoskeleton through integrin-coupled ferromagnetic beads coated with Arg-Gly-Asp (RGD) peptide. Measurements were made in two groups of cardiocytes from cats with right ventricular (RV) hypertrophy induced by pulmonary artery banding: (1) those from the pressure-overloaded RV and (2) those from the normally loaded same-animal control left ventricle (LV). Cytoskeletal stiffness increased almost twofold, from 8.53 +/- 0.77 dyne/cm2 in the normally loaded LV cardiocytes to 16.46 +/- 1.32 dyne/cm2 in the hypertrophied RV cardiocytes. Cytoskeletal apparent viscosity increased almost fourfold, from 20.97 +/- 1.92 poise in the normally loaded LV cardiocytes to 87.85 +/- 6.95 poise in the hypertrophied RV cardiocytes. In addition to these baseline data showing differing stiffness and, especially, apparent viscosity in the two groups of cardiocytes, microtubule depolymerization by colchicine was found to return both the stiffness and the apparent viscosity of the pressure overload-hypertrophied RV cells fully to normal. Conversely, microtubule hyperpolymerization by taxol increased the stiffness and apparent viscosity values of normally loaded LV cardiocytes to the abnormal values given above for pressure-hypertrophied RV cardiocytes. Thus, increased microtubule density constitutes primarily a viscous load on the cardiocyte contractile apparatus in pressure-overload cardiac hypertrophy.
Alekperov, I I; Dorofeeva, Z Z; Iurenev, A P
1981-11-01
In 47 patients with arterial hypertension and clinicoroentgenological signs of hypertrophy of the left ventricle the echo- and electrocardiographic study (the McFee-Parungao system) was carried out. Highly significant (p less than 0.001) direct correlation was revealed between the index of the corrected ECG, such as sigma R x,y,z + + sigma S x,y,z and Rx + Sz with echocardiographic indices of mass r = +0.851 and +0.848, respectively, and the thickness of the left ventricle of the myocardium (r = +0.806 and +0.794, respectively). The above electrocardiographic indices do not correlate to the main echocardiographic indices of the contractile function of the left ventricle.
Excessive training induces molecular signs of pathologic cardiac hypertrophy.
da Rocha, Alisson L; Teixeira, Giovana R; Pinto, Ana P; de Morais, Gustavo P; Oliveira, Luciana da C; de Vicente, Larissa Gaioto; da Silva, Lilian E C M; Pauli, José R; Cintra, Dennys E; Ropelle, Eduardo R; de Moura, Leandro P; Mekary, Rania A; de Freitas, Ellen C; da Silva, Adelino S R
2018-05-24
Chronic exercise induces cardiac remodeling that promotes left ventricular hypertrophy and cardiac functional improvement, which are mediated by the mammalian or the mechanistic target of rapamycin (mTOR) as well as by the androgen and glucocorticoid receptors (GRs). However, pathological conditions (i.e., chronic heart failure, hypertension, and aortic stenosis, etc.) also induce cardiac hypertrophy, but with detrimental function, high levels of proinflammatory cytokines and myostatin, elevated fibrosis, reduced adenosine monophosphate-activated protein kinase (AMPK) activation, and fetal gene reactivation. Furthermore, recent studies have evidenced that excessive training induced an inflammatory status in the serum, muscle, hypothalamus, and liver, suggesting a pathological condition that could also be detrimental to cardiac tissue. Here, we verified the effects of three running overtraining (OT) models on the molecular parameters related to physiological and pathological cardiac hypertrophy. C57BL/6 mice performed three different OT protocols and were evaluated for molecular parameters related to physiological and pathological cardiac hypertrophy, including immunoblotting, reverse transcription polymerase chain reaction, histology, and immunohistochemistry analyses. In summary, the three OT protocols induced left ventricle (LV) hypertrophy with signs of cardiac fibrosis and negative morphological adaptations. These maladaptations were accompanied by reductions in AMPKalpha (Thr172) phosphorylation, androgen receptor, and GR expressions, as well as by an increase in interleukin-6 expression. Specifically, the downhill running-based OT model reduced the content of some proteins related to the mTOR signaling pathway and upregulated the β-isoform of myosin heavy-chain gene expression, presenting signs of LV pathological hypertrophy development. © 2018 Wiley Periodicals, Inc.
Rivaud, Mathilde R; Jansen, John A; Postema, Pieter G; Nannenberg, Eline A; Mizusawa, Yuka; van der Nagel, Roel; Wolswinkel, Rianne; van der Made, Ingeborg; Marchal, Gerard A; Rajamani, Sridharan; Belardinelli, Luiz; van Tintelen, J Peter; Tanck, Michael W T; van der Wal, Allard C; de Bakker, Jacques M T; van Rijen, Harold V; Creemers, Esther E; Wilde, Arthur A M; van den Berg, Maarten P; van Veen, Toon A B; Bezzina, Connie R; Remme, Carol Ann
2018-04-27
Management of patients with inherited cardiac ion channelopathy is hindered by variability in disease severity and sudden cardiac death (SCD) risk. Here, we investigated the modulatory role of hypertrophy on arrhythmia and SCD risk in sodium channelopathy. Follow-up data was collected from 164 individuals positive for the SCN5A-1795insD founder mutation and 247 mutation-negative relatives. A total of 38 (obligate) mutation-positive patients died suddenly or suffered life-threatening ventricular arrhythmia. Of these, 18 were aged >40 years, a high proportion of which had a clinical diagnosis of hypertension and/or cardiac hypertrophy. While pacemaker implantation was highly protective in preventing bradycardia-related SCD in young mutation-positive patients, seven of them aged >40 experienced life-threatening arrhythmic events despite pacemaker treatment. Of these, six had a diagnosis of hypertension/hypertrophy, pointing to a modulatory role of this co-morbidity. Induction of hypertrophy in adult mice carrying the homologous mutation (Scn5a1798insD/+) caused SCD and excessive conduction disturbances, confirming a modulatory effect of hypertrophy in the setting of the mutation. The deleterious effects of the interaction between hypertrophy and the mutation were prevented by genetically impairing the pro-hypertrophic response and by pharmacological inhibition of the enhanced late sodium current associated with the mutation. This study provides the first evidence for a modulatory effect of co-existing cardiac hypertrophy on arrhythmia risk and treatment efficacy in inherited sodium channelopathy. Our findings emphasize the need for continued assessment and rigorous treatment of this co-morbidity in SCN5A mutation-positive individuals.
Qiao, Weiwei; Zhang, Weili; Gai, Yusheng; Zhao, Lan; Fan, Juexin
2014-06-13
Imbalance between histone acetylation/deacetylation critically participates in the expression of hypertrophic fetal genes and development of cardiac hypertrophy. While histone deacetylases play dual roles in hypertrophy, current evidence reveals that histone acetyltransferase such as p300 and PCAF act as pro-hypertrophic factors. However, it remains elusive whether some histone acetyltransferases can prevent the development of hypertrophy. Males absent on the first (MOF) is a histone acetyltransferase belonging to the MYST (MOZ, Ybf2/Sas3, Sas2 and TIP60) family. Here in this study, we reported that MOF expression was down-regulated in failing human hearts and hypertrophic murine hearts at protein and mRNA levels. To evaluate the roles of MOF in cardiac hypertrophy, we generated cardiac-specific MOF transgenic mice. MOF transgenic mice did not show any differences from their wide-type littermates at baseline. However, cardiac-specific MOF overexpression protected mice from transverse aortic constriction (TAC)-induced cardiac hypertrophy, with reduced radios of heart weight (HW)/body weight (BW), lung weight/BW and HW/tibia length, decreased left ventricular wall thickness and increased fractional shortening. We also observed lower expression of hypertrophic fetal genes in TAC-challenged MOF transgenic mice compared with that of wide-type mice. Mechanically, MOF overexpression increased the expression of Catalase and MnSOD, which blocked TAC-induced ROS and ROS downstream c-Raf-MEK-ERK pathway that promotes hypertrophy. Taken together, our findings identify a novel anti-hypertrophic role of MOF, and MOF is the first reported anti-hypertrophic histone acetyltransferase. Copyright © 2014 Elsevier Inc. All rights reserved.
Agarwal, Rajiv; Sinha, Arjun D.; Pappas, Maria K.; Abraham, Terri N.; Tegegne, Getachew G.
2014-01-01
Background The purpose of this study was to determine among maintenance hemodialysis patients with echocardiographic left ventricular hypertrophy and hypertension whether in comparison with a β-blocker-based antihypertensive therapy, an angiotensin converting enzyme-inhibitor-based antihypertensive therapy causes a greater regression of left ventricular hypertrophy. Methods Subjects were randomly assigned to either open-label lisinopril (n = 100) or atenolol (n = 100) each administered three times per week after dialysis. Monthly monitored home blood pressure (BP) was controlled to <140/90 mmHg with medications, dry weight adjustment and sodium restriction. The primary outcome was the change in left ventricular mass index (LVMI) from baseline to 12 months. Results At baseline, 44-h ambulatory BP was similar in the atenolol (151.5/87.1 mmHg) and lisinopril groups, and improved similarly over time in both groups. However, monthly measured home BP was consistently higher in the lisinopril group despite the need for both a greater number of antihypertensive agents and a greater reduction in dry weight. An independent data safety monitoring board recommended termination because of cardiovascular safety. Serious cardiovascular events in the atenolol group occurred in 16 subjects, who had 20 events, and in the lisinopril group in 28 subjects, who had 43 events {incidence rate ratio (IRR) 2.36 [95% confidence interval (95% CI) 1.36–4.23, P = 0.001]}. Combined serious adverse events of myocardial infarction, stroke and hospitalization for heart failure or cardiovascular death in the atenolol group occurred in 10 subjects, who had 11 events and in the lisinopril group in 17 subjects, who had 23 events (IRR 2.29, P = 0.021). Hospitalizations for heart failure were worse in the lisinopril group (IRR 3.13, P = 0.021). All-cause hospitalizations were higher in the lisinopril group [IRR 1.61 (95% CI 1.18–2.19, P = 0.002)]. LVMI improved with time; no difference between drugs was noted. Conclusions Among maintenance dialysis patients with hypertension and left ventricular hypertrophy, atenolol-based antihypertensive therapy may be superior to lisinopril-based therapy in preventing cardiovascular morbidity and all-cause hospitalizations. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases; ClinicalTrials.gov number: NCT00582114) PMID:24398888
Scansen, Brian A; Kent, Agnieszka M; Cheatham, Sharon L; Cheatham, John P; Cheatham, John D
2014-09-01
Two dogs with severe dysplastic pulmonary valve stenosis and right-to-left shunting defects (patent foramen ovale, perimembranous ventricular septal defect) underwent palliative stenting of the right ventricular outflow tract and pulmonary valve annulus using balloon expandable stents. One dog received 2 over-lapping bare metal stents placed 7 months apart; the other received a single covered stent. Both procedures were considered technically successful with a reduction in the transpulmonary valve pressure gradient from 202 to 90 mmHg in 1 dog and from 168 to 95 mmHg in the other. Clinical signs of exercise intolerance and syncope were temporarily resolved in both dogs. However, progressive right ventricular concentric hypertrophy, recurrent stenosis, and erythrocytosis were observed over the subsequent 6 months leading to poor long-term outcomes. Stenting of the right ventricular outflow tract is feasible in dogs with severe dysplastic pulmonary valve stenosis, though further study and optimization of the procedure is required. Copyright © 2014 Elsevier B.V. All rights reserved.
Cardiovascular Disease Risk in Children With Kidney Disease.
Sethna, Christine B; Merchant, Kumail; Reyes, Abigail
2018-05-01
Cardiovascular disease is a major cause of death in individuals diagnosed with kidney disease during childhood. Children with kidney disease often incur a significant cardiovascular burden that leads to increased risk for cardiovascular disease. Evidence has shown that children with kidney disease, including chronic kidney disease, dialysis, kidney transplantation, and nephrotic syndrome, develop abnormalities in cardiovascular markers such as hypertension, dyslipidemia, left ventricular hypertrophy, left ventricular dysfunction, atherosclerosis, and aortic stiffness. Early identification of modifiable risk factors and treatment may lead to a decrease of long-term cardiovascular morbidity and mortality, but evidence in this population is lacking. Copyright © 2018 Elsevier Inc. All rights reserved.
Manegold, C; Patzschke, U
1979-06-08
Typical signs of left ventricular hypertrophy (LVH) were present in the ECG of 36 (10 women, 26 men) of 127 persons with essential hypertension (46 women, 81 men). After a two-year course of combined drug treatment (chlortalidone, reserpine, methyl-dopa, hydralazine) with effective blood-pressure reduction LVH was still present in the ECG of 29, after a four-year course of only 15 among 36, i. e. a reduction in the presence of LVH of nearly 60%. Since the patients' body-weight remained unchanged during this period, the regression in ECG changes is ascribed to the effectiveness of the drug treatment.
Daicho, Takuya; Yagi, Tatsuya; Abe, Yohei; Ohara, Meiko; Marunouchi, Tetsuro; Takeo, Satoshi; Tanonaka, Kouichi
2009-09-01
The present study was undertaken to explore the possible involvement of alterations in the mitochondrial energy-producing ability in the development of the right ventricular failure in monocrotaline-administered rats. The rats at the 6th week after subcutaneous injection of 60 mg/kg monocrotaline revealed marked myocardial hypertrophy and fibrosis, that is, severe cardiac remodeling. The time-course study on the cardiac hemodynamics of the monocrotaline-administered rat by the cannula and echocardiographic methods showed a reduction in cardiac double product, a decrease in cardiac output index, and an increase in the right ventricular Tei index, suggesting that the right ventricular failure was induced at the 6th week after monocrotaline administration in rats. The mitochondrial oxygen consumption rate of the right ventricular muscle isolated from the monocrotaline-administered animal was decreased, which was associated with a reduction in myocardial high-energy phosphates. Furthermore, the decrease in mitochondrial oxygen consumption rate was inversely related to the increase in the right ventricular Tei index of the monocrotaline-administered rats. These results suggest that impairment of the mitochondrial energy-producing ability is involved in the development of the right ventricular failure in monocrotaline-induced pulmonary hypertensive rats.
Han, June-Chiew; Guild, Sarah-Jane; Pham, Toan; Nisbet, Linley; Tran, Kenneth; Taberner, Andrew J.; Loiselle, Denis S.
2018-01-01
Pulmonary arterial hypertension (PAH) alters the geometries of both ventricles of the heart. While the right ventricle (RV) hypertrophies, the left ventricle (LV) atrophies. Multiple lines of clinical and experimental evidence lead us to hypothesize that the impaired stroke volume and systolic pressure of the LV are a direct consequence of the effect of pressure overload in the RV, and that atrophy in the LV plays only a minor role. In this study, we tested this hypothesis by examining the mechanoenergetic response of the atrophied LV to RV hypertrophy in rats treated with monocrotaline. Experiments were performed across multiple-scales: the whole-heart in vivo and ex vivo, and its trabeculae in vitro. Under the in vivo state where the RV was pressure-overloaded, we measured reduced systemic blood pressure and LV ventricular pressure. In contrast, under both ex vivo and in vitro conditions, where the effect of RV pressure overload was circumvented, we found that LV was capable of developing normal systolic pressure and stress. Nevertheless, LV atrophy played a minor role in that LV stroke volume remained lower, thereby contributing to lower LV mechanical work output. Concomitantly lower oxygen consumption and change of enthalpy were observed, and hence LV energy efficiency was unchanged. Our internally consistent findings between working-heart and trabecula experiments explain the rapid improvement of LV systolic function observed in patients with chronic pulmonary hypertension following surgical relief of RV pressure overload. PMID:29375394
Leibowitz, David; Planer, David; Ben-Ivgi, Fanny; Weiss, A Teddy; Bursztyn, Michael
2005-01-01
The objective of this prospective study was to examine the association between serum levels of TNF (tumor-necrosis factor) and IL-6 (interleukin-6) and left ventricular mass in hypertensive patients. Hypertensive patients currently receiving medical therapy were eligible. All subjects underwent echocardiography with measurements of left ventricular (LV) mass and ejection fraction (EF) and had serum levels of TNF and IL-6 measured by ELISA immunoassay. 35 subjects (20F, 15M; mean age 56.4 +/- 10.5 yrs) were studied. 19 patients (54%) had elevated LV mass. Of these patients, 6 (32%) had detectable serum TNF levels and 1 (7%) had detectable IL-6 levels, (p = NS). Hypertensive patients with elevated LV mass do not consistently exhibit elevated cytokine levels when compared to those with normal LV mass.
John Paul Jones: An Overlooked Autopsy Finding that May Explain His Terminal Illness.
Hamrell, Burt B
2016-03-01
A finding in the autopsy of John Paul Jones, the American Revolutionary War naval hero, may explain his terminal illness. During his last 2 years, he had a persistent productive cough and dyspnea. Ten days before death, he developed rapidly progressive dependent edema and ascites. He died in France in 1792. His body, preserved in alcohol in a lead coffin, was, in 1905, removed to the United States. Glomerulonephritis was noted on an autopsy, performed in France, but there was no comment then or since about ventricular wall thickness being the same in both ventricles at 5-6 mm. Hypertrophy and dilatation with biventricular failure followed by tissue shrinkage during 113 years in alcohol could have resulted in these ventricular wall findings. Systemic hypertension and left ventricular failure are consistent with his respiratory symptoms complicated perhaps by pulmonary emboli, right ventricular failure with tricuspid regurgitation, peripheral congestion, and jaundice. © 2015 American Academy of Forensic Sciences.
Maiello, Maria; Zito, Annapaola; Carbonara, Santa; Ciccone, Marco Matteo; Palmiero, Pasquale
2017-10-01
Coronary artery disease (CAD) is quite common among diabetic patients, our study goal is to detect the prevalence of left ventricular (LV) adverse changes in geometry, mass and diastolic function on diabetic, but not hypertensive patients, with coronary artery disease(CAD) and LV ejection fraction(LVEF)>45%, actually unknown, because of current guidelines that do not include echocardiographic assessment for follow up of diabetic patients. 665 consecutive diabetic patients (443 females, mean age 66±9years), performed a complete echocardiographic assessment according to current ASE echo-guidelines: diastolic dysfunction (DD), eccentric hypertrophy (EH), concentric hypertrophy (CH) and concentric remodeling (CR) of LV were reported. CAD was assessed only by reports of bypass surgery, angioplasty or patients hospitalized for acute myocardial infarction. 218 patients (32.8%) presented LV changes: LVDD 49 (7.4%), LVEH 68 (10.2%), LVDD and EH 46 (6.9%), LVDD and CH 36 (5.4%), LVDD and CR 19 (2.9%). 447 (67.2%) had no LV changes. 81 (12.1%) patients with CAD, presented: LVDD 17 (21%), LVEH 32 (39.5%), LVDD and EH 9 (11.1%), LVDD and CH 7 (8.6%), LVDD and CR 8 (9.9%), 8 (9.9%) had no LV adverse changes. There were among CAD patients, a significantly higher prevalence of LVDD (p<0.02), LV eccentric hypertrophy (EH) (p<0.05), DD and LVEH (p<0.04), DD and LV concentric hypertrophy(CH) (p<0.03) and DD and LV concentric remodeling (p<0.02), when compared with those patients without CAD. CAD is related to all different patterns of LV adverse changes in mass, geometry and diastolic function, with a significantly higher prevalence in our population of diabetic patients with normal systolic function. These changes however remain unrecognized until they undergo to a conventional echocardiographic assessment. We support this tool need to be included into future guidelines concerning follow-up of diabetic patients. Copyright © 2017 Elsevier Inc. All rights reserved.
Nakanishi, Koki; Jin, Zhezhen; Homma, Shunichi; Elkind, Mitchell S V; Rundek, Tatjana; Tugcu, Aylin; Sacco, Ralph L; Di Tullio, Marco R
2017-07-30
Left ventricular (LV) hypertrophy and subclinical cerebrovascular disease are early manifestations of cardiac and brain target organ damage caused by hypertension. This study aimed to investigate whether intensive office systolic blood pressure (SBP) control has beneficial effects on LV morphology and function and subclinical cerebrovascular disease in elderly patients with hypertension. We examined 420 patients treated for hypertension without history of heart failure and stroke from the CABL (Cardiovascular Abnormalities and Brain Lesions) study. All patients underwent 2-dimensional echocardiographic examination and brain magnetic resonance imaging. Subclinical cerebrovascular disease was defined as silent brain infarcts and white matter hyperintensity volume. Patients were divided into 3 groups: SBP <120 mm Hg (intensive control); SBP 120 to 139 mm Hg (less intensive control); and SBP ≥140 mm Hg (uncontrolled). Prevalence of LV hypertrophy and diastolic dysfunction were lowest in the intensive control, intermediate in the less intensive control, and highest in the uncontrolled groups (12.8%, 31.8%, and 44.7%, respectively [ P <0.001], for LV hypertrophy; 46.8%, 61.7%, and 72.6%, respectively [ P =0.003], for diastolic dysfunction). Patients with less intensive SBP control had greater risk of LV hypertrophy than those with intensive control (adjusted odds ratio, 3.26; P =0.013). A similar trend was observed for LV diastolic dysfunction but did not reach statistical significance (adjusted odds ratio, 1.65; P =0.144). Conversely, intensive SBP control was not significantly associated with reduced risk of silent brain infarcts and white matter hyperintensity volume compared with less intensive control. Compared with less intensive control, intensive SBP control may have a stronger beneficial effect on cardiac than cerebral subclinical disease. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Ding, Yuan-Yuan; Li, Jing-Mei; Guo, Feng-Jie; Liu, Ya; Tong, Yang-Fei; Pan, Xi-Chun; Lu, Xiao-Lan; Ye, Wen; Chen, Xiao-Hong; Zhang, Hai-Gang
2016-01-01
The forkhead/winged helix transcription factor (Fox) p3 can regulate the expression of various genes, and it has been reported that the transfer of Foxp3-positive T cells could ameliorate cardiac hypertrophy and fibrosis. Triptolide (TP) can elevate the expression of Foxp3, but its effects on cardiac hypertrophy remain unclear. In the present study, neonatal rat ventricular myocytes (NRVM) were isolated and stimulated with angiotensin II (1 μmol/L) to induce hypertrophic response. The expression of Foxp3 in NRVM was observed by using immunofluorescence assay. Fifty mice were randomly divided into five groups and received vehicle (control), isoproterenol (Iso, 5 mg/kg, s.c.), one of three doses of TP (10, 30, or 90 μg/kg, i.p.) for 14 days, respectively. The pathological morphology changes were observed after Hematoxylin and eosin, lectin and Masson’s trichrome staining. The levels of serum brain natriuretic peptide (BNP) and troponin I were determined by enzyme-linked immunosorbent assay and chemiluminescence, respectively. The mRNA and protein expressions of α- myosin heavy chain (MHC), β-MHC and Foxp3 were determined using real-time PCR and immunohistochemistry, respectively. It was shown that TP (1, 3, 10 μg/L) treatment significantly decreased cell size, mRNA and protein expression of β-MHC, and upregulated Foxp3 expression in NRVM. TP also decreased heart weight index, left ventricular weight index and, improved myocardial injury and fibrosis; and decreased the cross-scetional area of the myocardium, serum cardiac troponin and BNP. Additionally, TP markedly reduced the mRNA and protein expression of myocardial β-MHC and elevated the mRNA and protein expression of α-MHC and Foxp3 in a dose-dependent manner. In conclusion, TP can effectively ameliorate myocardial damage and inhibit cardiac hypertrophy, which is at least partly related to the elevation of Foxp3 expression in cardiomyocytes. PMID:27965581
Tissier, R; Chetboul, V; Moraillon, R; Nicolle, A; Carlos, C; Enriquez, B; Pouchelon, J-L
2005-01-01
The aim of this article is to describe original adverse effects in two dogs chronically treated with the inodilator pimobendan. We report a German shepherd (i.e., dog 1) and a poodle (i.e., dog 2) that were referred to our cardiology unit after receiving pimobendan for 10 and 5 mo, respectively. In both dogs, conventional echo-Doppler examination demonstrated mitral valve regurgitation and myocardial hypertrophy. Tissue Doppler imaging (TDI) was performed in the first case and revealed an abnormal relaxation phase. After the first examination, pimobendan administration was stopped in both cases and dogs were re-examined 3 and 1 mo later, respectively. Mitral valve regurgitation assessed by echocardiography decreased in both dogs, and the systolic heart murmur disappeared in dog 1. Importantly, most echocardiographic and TDI parameters tended to normalize in dog 1, suggesting, at least partial reversal of both myocardial hypertrophy and relaxation abnormality produced during inodilator therapy. This is the first report to describe an increase in mitral regurgitation under clinical conditions in dogs treated with pimobendan. We also suggest that pimobendan may induce ventricular hypertrophy. However, prospective studies are needed to confirm this observation.
Reducing RBM20 activity improves diastolic dysfunction and cardiac atrophy.
Hinze, Florian; Dieterich, Christoph; Radke, Michael H; Granzier, Henk; Gotthardt, Michael
2016-12-01
Impaired diastolic filling is a main contributor to heart failure with preserved ejection fraction (HFpEF), a syndrome with increasing prevalence and no treatment. Both collagen and the giant sarcomeric protein titin determine diastolic function. Since titin's elastic properties can be adjusted physiologically, we evaluated titin-based stiffness as a therapeutic target. We adjusted RBM20-dependent cardiac isoform expression in the titin N2B knockout mouse with increased ventricular stiffness. A ~50 % reduction of RBM20 activity does not only maintain cardiac filling in diastole but also ameliorates cardiac atrophy and thus improves cardiac function in the N2B-deficient heart. Reduced RBM20 activity partially normalized gene expression related to muscle development and fatty acid metabolism. The adaptation of cardiac growth was related to hypertrophy signaling via four-and-a-half lim-domain proteins (FHLs) that translate mechanical input into hypertrophy signals. We provide a novel link between cardiac isoform expression and trophic signaling via FHLs and suggest cardiac splicing as a therapeutic target in diastolic dysfunction. Increasing the length of titin isoforms improves ventricular filling in heart disease. FHL proteins are regulated via RBM20 and adapt cardiac growth. RBM20 is a therapeutic target in diastolic dysfunction.
Dimensional correlates of left ventricular dilation in the presence of hypertrophy.
Al-Nouri, M B; Ford, L E; Wix, H
1983-01-01
Twelve normal subjects, 50 patients with valvular heart disease, and 14 with hypertension were studied. Those with valvular disease were divided into two groups: 28 with angiographically measured ejection fractions greater than or equal to 0.6 and 22 with ejection fractions less than 0.6. The echocardiographically measured ventricular thickness divided by radius ratio (t/r) was approximately proportional to peak systolic pressure (P) in all groups having ejection fractions greater than or equal to 0.6, so that the t/r divided by P ratios were nearly the same. Patients with ejection fractions less than 0.6 had significantly lower t/r divided by P values. No single component of the t/r divided by P ratio would identify the patients with lower ejection fractions. The t/r divided by P ratios in 14 hypertensive patients were nearly identical to the ratios in six patients with aortic stenosis and ejection fractions greater than or equal to 0.6, indicating that an aortic valve gradient does not cause a grossly abnormal form of pressure hypertrophy. The t/r ratio is thus a double sensitive, noninvasive index of dilation when correlated with systolic pressure.
Maron, B J
2009-09-01
Sudden cardiac death in young competitive athletes is an important public health problem, although a relatively low-event-rate phenomenon. The single most common cardiovascular cause of these unexpected catastrophes is hypertrophic cardiomyopathy (HCM), accounting for about one-third of cases. Since the phenotypic expression of HCM is variable, and not uncommonly includes patients with mild and localised left ventricular hypertrophy, the differential diagnosis with physiological remodelling of athlete's heart not uncommonly arises. This review discusses those non-invasive strategies that are useful in distinguishing the benign consequences of systematic athletic training from pathological left ventricular hypertrophy with the potential for sudden cardiac death. Preparticipation screening in healthy general athlete populations may raise the suspicion of HCM, and ultimately lead to definitive diagnosis. However, recently controversy has arisen regarding the most effective and practical strategy for the screening of athletes. European investigators have promoted routine 12-lead ECGs as part of a national mandatory programme distinct from the customary practice in the US which is limited to history and physical examinations. Consensus criteria and recommendations for eligibility and disqualification of athletes with HCM (and other cardiovascular abnormalities) have proved useful to the practising community.
Brohet, C R; Richman, H G
1979-06-01
Automated processing of electrocardiograms by the Veterans Administration program was evaluated for both agreement with physician interpretation and interpretative accuracy as assessed with nonelectrocardiographic criteria. One thousand unselected electrocardiograms were analyzed by two reviewer groups, one familiar and the other unfamiliar with the computer program. A significant number of measurement errors involving repolarization changes and left axis deviation occurred; however, interpretative disagreements related to statistical decision were largely language-related. Use of a printout with a more traditional format resulted in agreement with physician interpretation by both reviewer groups in more than 80 percent of cases. Overall sensitivity based on agreement with nonelectrocardiographic criteria was significantly greater with use of the computer program than with use of the conventional criteria utilized by the reviewers. This difference was particularly evident in the subgroup analysis of myocardial infarction and left ventricular hypertrophy. The degree of overdiagnosis of left ventricular hypertrophy and posteroinferior infarction was initially unacceptable, but this difficulty was corrected by adjustment of probabilities. Clinical acceptability of the Veterans Administration program appears to require greater physician education than that needed for other computer programs of electrocardiographic analysis; the flexibility of interpretation by statistical decision offers the potential for better diagnostic accuracy.
Geographic variation in left ventricular mass and mass index: a systematic review.
Poppe, K K; Bachmann, M Edgerton; Triggs, C M; Doughty, R N; Whalley, G A
2012-07-01
Left ventricular (LV) hypertrophy, defined as an abnormal increase in LV mass (LVM), is an important prognostic indicator and therapeutic target. LVM is often divided by body surface area to derive indexed mass; however, this does not correctly identify pathological LV hypertrophy in all people, especially when body composition is altered, or in different ethnic groups. We evaluated published ranges of echocardiographic LVM in healthy adult populations from different countries, excluding control groups, and compared them with the American Society of Echocardiography reference ranges. A total of 33 studies met the inclusion criteria. In men and women, there was wide variation in the ranges of LVM with a tendency for the upper limit to increase geographically westward; this variation remained for indexed mass. Several ranges fell outside the upper reference limits: in men, 13 of the mass ranges and 16 of indexed mass; and in women, 8 mass and 16 indexed mass. This review has shown that current guidelines may need revision as some published series suggest that greater LV mass should be considered normal. This may be explained by ethnic differences and supports the need for widely applicable and ethnically diverse reference ranges to be established.
Sezai, Akira; Soma, Masayoshi; Hata, Mitsumasa; Yoshitake, Isamu; Unosawa, Satoshi; Wakui, Shinji; Shiono, Motomi
2011-01-01
Various angiotensin II receptor blockers are widely used for the treatment of hypertension in recent years. The results of large-scale clinical studies have shown that they have various efficacies: not only hypotensive effects but also organ protective effects. In this study, the effects of a change-over from candesartan to olmesartan on renin-angiotensin-aldsterone system, cardiomegaly and peripheral circulation were studied. Participants enrolled in this trial were outpatients with essential hypertension after cardiac surgery who had received candesartan for more than one year. Fifty-six patients switched from candesartan to olmesartan. The primary endpoints were 1) renin activity, angiotensin II, aldosterone, and 2) left ventricular mass index (LVMI). It was clear that angiotensin II and aldosterone are decreased by the potent hypotensive effects of olmesartan in a change-over from candesartan to olmesartan. Since LVMI and BNP were decreased, inhibitory effects on myocardial hypertrophy were also confirmed. In the present study, left ventricular hypertrophy and on arterial compliance were inhibited by a decrease in angiotensin II and aldosterone due to the change-over to olmesartan. In the future, protective effects on organs will be clarified by long-term observations.
Role of STIM1 (Stromal Interaction Molecule 1) in Hypertrophy-Related Contractile Dysfunction.
Troupes, Constantine D; Wallner, Markus; Borghetti, Giulia; Zhang, Chen; Mohsin, Sadia; von Lewinski, Dirk; Berretta, Remus M; Kubo, Hajime; Chen, Xiongwen; Soboloff, Jonathan; Houser, Steven
2017-07-07
Pathological increases in cardiac afterload result in myocyte hypertrophy with changes in myocyte electrical and mechanical phenotype. Remodeling of contractile and signaling Ca 2+ occurs in pathological hypertrophy and is central to myocyte remodeling. STIM1 (stromal interaction molecule 1) regulates Ca 2+ signaling in many cell types by sensing low endoplasmic reticular Ca 2+ levels and then coupling to plasma membrane Orai channels to induce a Ca 2+ influx pathway. Previous reports suggest that STIM1 may play a role in cardiac hypertrophy, but its role in electrical and mechanical phenotypic alterations is not well understood. To define the contributions of STIM1-mediated Ca 2+ influx on electrical and mechanical properties of normal and diseased myocytes, and to determine whether Orai channels are obligatory partners for STIM1 in these processes using a clinically relevant large animal model of hypertrophy. Cardiac hypertrophy was induced by slow progressive pressure overload in adult cats. Hypertrophied myocytes had increased STIM1 expression and activity, which correlated with altered Ca 2 + -handling and action potential (AP) prolongation. Exposure of hypertrophied myocytes to the Orai channel blocker BTP2 caused a reduction of AP duration and reduced diastolic Ca 2+ spark rate. BTP2 had no effect on normal myocytes. Forced expression of STIM1 in cultured adult feline ventricular myocytes increased diastolic spark rate and prolonged AP duration. STIM1 expression produced an increase in the amount of Ca 2+ stored within the sarcoplasmic reticulum and activated Ca 2+ /calmodulin-dependent protein kinase II. STIM1 expression also increased spark rates and induced spontaneous APs. STIM1 effects were eliminated by either BTP2 or by coexpression of a dominant negative Orai construct. STIM1 can associate with Orai in cardiac myocytes to produce a Ca 2+ influx pathway that can prolong the AP duration and load the sarcoplasmic reticulum and likely contributes to the altered electromechanical properties of the hypertrophied heart. © 2017 American Heart Association, Inc.
Higashikuni, Yasutomi; Tanaka, Kimie; Kato, Megumi; Nureki, Osamu; Hirata, Yasunobu; Nagai, Ryozo; Komuro, Issei; Sata, Masataka
2013-01-01
Background Inflammation is induced in the heart during the development of cardiac hypertrophy. The initiating mechanisms and the role of inflammation in cardiac hypertrophy, however, remain unclear. Toll‐like receptor‐2 (TLR2) recognizes endogenous molecules that induce noninfectious inflammation. Here, we examined the role of TLR2‐mediated inflammation in cardiac hypertrophy. Methods and Results At 2 weeks after transverse aortic constriction, Tlr2−/− mice showed reduced cardiac hypertrophy and fibrosis with greater left ventricular dilatation and impaired systolic function compared with wild‐type mice, which indicated impaired cardiac adaptation in Tlr2−/− mice. Bone marrow transplantation experiment revealed that TLR2 expressed in the heart, but not in bone marrow–derived cells, is important for cardiac adaptive response to pressure overload. In vitro experiments demonstrated that TLR2 signaling can induce cardiomyocyte hypertrophy and fibroblast and vascular endothelial cell proliferation through nuclear factor–κB activation and interleukin‐1β upregulation. Systemic administration of a nuclear factor–κB inhibitor or anti–interleukin‐1β antibodies to wild‐type mice resulted in impaired adaptive cardiac hypertrophy after transverse aortic constriction. We also found that heat shock protein 70, which was increased in murine plasma after transverse aortic constriction, can activate TLR2 signaling in vitro and in vivo. Systemic administration of anti–heat shock protein 70 antibodies to wild‐type mice impaired adaptive cardiac hypertrophy after transverse aortic constriction. Conclusions Our results demonstrate that TLR2‐mediated inflammation induced by extracellularly released heat shock protein 70 is essential for adaptive cardiac hypertrophy in response to pressure overload. Thus, modulation of TLR2 signaling in the heart may provide a novel strategy for treating heart failure due to inadequate adaptation to hemodynamic stress. PMID:24249711
Flett, Andrew S.; Maestrini, Viviana; Milliken, Don; Fontana, Mariana; Treibel, Thomas A.; Harb, Rami; Sado, Daniel M.; Quarta, Giovanni; Herrey, Anna; Sneddon, James; Elliott, Perry; McKenna, William; Moon, James C.
2015-01-01
Background Diagnosis of apical HCM utilizes conventional wall thickness criteria. The normal left ventricular wall thins towards the apex such that normal values are lower in the apical versus the basal segments. The impact of this on the diagnosis of apical hypertrophic cardiomyopathy has not been evaluated. Methods We performed a retrospective review of 2662 consecutive CMR referrals, of which 75 patients were identified in whom there was abnormal T-wave inversion on ECG and a clinical suspicion of hypertrophic cardiomyopathy. These were retrospectively analyzed for imaging features consistent with cardiomyopathy, specifically: relative apical hypertrophy, left atrial dilatation, scar, apical cavity obliteration or apical aneurysm. For comparison, the same evaluation was performed in 60 healthy volunteers and 50 hypertensive patients. Results Of the 75 patients, 48 met conventional HCM diagnostic criteria and went on to act as another comparator group. Twenty-seven did not meet criteria for HCM and of these 5 had no relative apical hypertrophy and were not analyzed further. The remaining 22 patients had relative apical thickening with an apical:basal wall thickness ratio > 1 and a higher prevalence of features consistent with a cardiomyopathy than in the control groups with 54% having 2 or more of the 4 features. No individual in the healthy volunteer group had more than one feature and no hypertension patient had more than 2. Conclusion A cohort of individuals exist with T wave inversion, relative apical hypertrophy and additional imaging features of HCM suggesting an apical HCM phenotype not captured by existing diagnostic criteria. PMID:25666123
Hydrogen gas improves left ventricular hypertrophy in Dahl rat of salt-sensitive hypertension.
Matsuoka, Hiroki; Miyata, Seiko; Okumura, Nozomi; Watanabe, Takuya; Hashimoto, Katsunori; Nagahara, Miki; Kato, Kazuko; Sobue, Sayaka; Takeda, Kozue; Ichihara, Masatoshi; Iwamoto, Takashi; Noda, Akiko
2018-06-14
Hypertension is an important risk factor for death resulting from stroke, myocardial infarction, and end-stage renal failure. Hydrogen (H 2 ) gas protects against many diseases, including ischemia-reperfusion injury and stroke. The effects of H 2 on hypertension and its related left ventricular (LV) function have not been fully elucidated. The purpose of this study was to investigate the effects of H 2 gas on hypertension and LV hypertrophy using echocardiography. Dahl salt-sensitive (DS) rats were randomly divided into three groups: those fed an 8% NaCl diet until 12 weeks of age (8% NaCl group), those additionally treated with H 2 gas (8% NaCl + H 2 group), and control rats maintained on a diet containing 0.3% NaCl until 12 weeks of age (0.3% NaCl group). H 2 gas was supplied through a gas flowmeter and delivered by room air (2% hydrogenated room air, flow rate of 10 L/min) into a cage surrounded by an acrylic chamber. We evaluated interventricular septal wall thickness (IVST), LV posterior wall thickness (LVPWT), and LV mass using echocardiography. IVST, LVPWT, and LV mass were significantly higher in the 8% NaCl group than the 0.3% NaCl group at 12 weeks of age, whereas they were significantly lower in the 8% NaCl + H 2 group than the 8% NaCl group. There was no significant difference in systolic blood pressure between the two groups. Our findings suggest that chronic H 2 gas inhalation may help prevent LV hypertrophy in hypertensive DS rats.
Abdulrahman, Nabeel; Jaspard-Vinassa, Beatrice; Fliegel, Larry; Jabeen, Aayesha; Riaz, Sadaf; Gadeau, Alain-Pierre; Mraiche, Fatima
2018-05-01
Cardiovascular diseases are the leading cause of death worldwide. One in three cases of heart failure is due to dilated cardiomyopathy. The Na + /H + exchanger isoform 1 (NHE1), a multifunctional protein and the key pH regulator in the heart, has been demonstrated to be increased in this condition. We have previously demonstrated that elevated NHE1 activity induced cardiac hypertrophy in vivo. Furthermore, the overexpression of active NHE1 elicited modulation of gene expression in cardiomyocytes including an upregulation of myocardial osteopontin (OPN) expression. To determine the role of OPN in inducing NHE1-mediated cardiomyocyte hypertrophy, double transgenic mice expressing active NHE1 and OPN knockout were generated and assessed by echocardiography and the cardiac phenotype. Our studies showed that hearts expressing active NHE1 exhibited cardiac remodeling indicated by increased systolic and diastolic left ventricular internal diameter and increased ventricular volume. Moreover, these hearts demonstrated impaired function with decreased fractional shortening and ejection fraction. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) mRNA was upregulated, and there was an increase in heart cell cross-sectional area confirming the cardiac hypertrophic effect. Moreover, NHE1 transgenic mice also showed increased collagen deposition, upregulation of CD44 and phosphorylation of p90 ribosomal s6 kinase (RSK), effects that were regressed in OPN knockout mice. In conclusion, we developed an interesting comparative model of active NHE1 transgenic mouse lines which express a dilated hypertrophic phenotype expressing CD44 and phosphorylated RSK, effects which were regressed in absence of OPN.
Smerup, Morten; Damkjær, Mads; Brøndum, Emil; Baandrup, Ulrik T; Kristiansen, Steen Buus; Nygaard, Hans; Funder, Jonas; Aalkjær, Christian; Sauer, Cathrine; Buchanan, Rasmus; Bertelsen, Mads Frost; Østergaard, Kristine; Grøndahl, Carsten; Candy, Geoffrey; Hasenkam, J Michael; Secher, Niels H; Bie, Peter; Wang, Tobias
2016-02-01
Giraffes--the tallest extant animals on Earth--are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures to calculate left ventricular wall stress. Cardiac output was also determined by inert gas rebreathing to provide an additional and independent estimate of stroke volume. Echocardiography and inert gas-rebreathing yielded similar cardiac outputs of 16.1±2.5 and 16.4±1.4 l min(-1), respectively. End-diastolic and end-systolic volumes were 521±61 ml and 228±42 ml, respectively, yielding an ejection fraction of 56±4% and a stroke volume of 0.59 ml kg(-1). Left ventricular circumferential wall stress was 7.83±1.76 kPa. We conclude that, relative to body mass, a small left ventricular cavity and a low stroke volume characterizes the giraffe heart. The adaptations result in typical mammalian left ventricular wall tensions, but produce a lowered cardiac output. © 2016. Published by The Company of Biologists Ltd.
Long-term physical exercise and atrial natriuretic peptide in obese Zucker rats.
Pörsti, Ilkka; Kähönen, Mika; Wu, Xiumin; Arvola, Pertti; Ruskoaho, Heikki
2002-07-01
Endurance training increases natriuretic peptide synthesis in the hypertrophied myocardium of spontaneously hypertensive rats. We examined the effects of 22-week-long treadmill exercise on plasma and tissue atrial natriuretic peptide in Zucker rats, a model of genetic obesity and moderate hypertension without clear cardiac hypertrophy. The blood pressures of the animals were measured by the tail-cuff method, and plasma and tissue samples for the peptide determinations were taken at the end of the study. The training increased heart weight to body weight ratio, while atrial natriuretic peptide contents in the right and left atrium, ventricular tissue, and plasma did not change. The exercise prevented the elevation of blood pressure, which was observed in non-exercised obese Zucker rats, and also reduced blood pressure in the lean rats. In conclusion, these results suggest that in the absence of preceding myocardial hypertrophy, the long-term exercise-induced workload is not deleterious to the heart in experimental obesity, since no changes in plasma and tissue atrial natriuretic peptide were detected.
Trichostatin A accentuates doxorubicin-induced hypertrophy in cardiac myocytes
Karagiannis, Tom C; Lin, Ann JE; Ververis, Katherine; Chang, Lisa; Tang, Michelle M; Okabe, Jun; El-Osta, Assam
2010-01-01
Histone deacetylase inhibitors represent a new class of anticancer therapeutics and the expectation is that they will be most effective when used in combination with conventional cancer therapies, such as the anthracycline, doxorubicin. The dose-limiting side effect of doxorubicin is severe cardiotoxicity and evaluation of the effects of combinations of the anthracycline with histone deacetylase inhibitors in relevant models is important. We used a well-established in vitro model of doxorubicin-induced hypertrophy to examine the effects of the prototypical histone deacetylase inhibitor, Trichostatin A. Our findings indicate that doxorubicin modulates the expression of the hypertrophy-associated genes, ventricular myosin light chain-2, the alpha isoform of myosin heavy chain and atrial natriuretic peptide, an effect which is augmented by Trichostatin A. Furthermore, we show that Trichostatin A amplifies doxorubicin-induced DNA double strand breaks, as assessed by γH2AX formation. More generally, our findings highlight the importance of investigating potential side effects that may be associated with emerging combination therapies for cancer. PMID:20930262
Trichostatin A accentuates doxorubicin-induced hypertrophy in cardiac myocytes.
Karagiannis, Tom C; Lin, Ann J E; Ververis, Katherine; Chang, Lisa; Tang, Michelle M; Okabe, Jun; El-Osta, Assam
2010-10-01
Histone deacetylase inhibitors represent a new class of anticancer therapeutics and the expectation is that they will be most effective when used in combination with conventional cancer therapies, such as the anthracycline, doxorubicin. The dose-limiting side effect of doxorubicin is severe cardiotoxicity and evaluation of the effects of combinations of the anthracycline with histone deacetylase inhibitors in relevant models is important. We used a well-established in vitro model of doxorubicin-induced hypertrophy to examine the effects of the prototypical histone deacetylase inhibitor, Trichostatin A. Our findings indicate that doxorubicin modulates the expression of the hypertrophy-associated genes, ventricular myosin light chain-2, the alpha isoform of myosin heavy chain and atrial natriuretic peptide, an effect which is augmented by Trichostatin A. Furthermore, we show that Trichostatin A amplifies doxorubicin-induced DNA double strand breaks, as assessed by γH2AX formation. More generally, our findings highlight the importance of investigating potential side effects that may be associated with emerging combination therapies for cancer.
Wang, W M; Liu, Z; Chen, G
2016-05-20
As the most common cardiac disease, myocardial infarction is followed by hypertrophy of cardiac myocytes and reconstruction of ventricular structure. The up-regulation of a series of factors including metalloproteinases, inflammatory factors, and growth factors after primary infarction lead to the hypertrophy, apoptosis, necrosis, and fibroblast proliferation in cardiac muscle tissues. Recent studies have reported on the potency of small interfering RNA (siRNA) in treating cardiac diseases. We thus investigated the efficacy of inducible co-stimulatory molecule (ICOS)-specific siRNA silencing in myocardial hypertrophy in a cardiac infarction rat model. This cardiac infarction model was prepared by ligating the left anterior descending coronary artery. ICOS-siRNA treatment was administered in parallel with non-sense siRNA. After 18 days, the cross-sectional area of cardiac muscle tissues and the left ventricle weight index were measured, along with ICOS mRNA and protein expression levels, and pathological staining. Compared to those in the control groups, in myocardial infarcted rats, the application of ICOS-siRNA effectively decreased the left ventricle weight index, as well as the surface area of cardiac myocytes. Both mRNA and protein levels of ICOS were also significantly decreased. HE staining was consistent with these results. In conclusion, ICOS-targeted siRNA can effectively silence gene expression of ICOS, and provided satisfactory treatment efficacy for myocardial cell hypertrophy after infarction.
Tham, Yow Keat; Bernardo, Bianca C; Ooi, Jenny Y Y; Weeks, Kate L; McMullen, Julie R
2015-09-01
The onset of heart failure is typically preceded by cardiac hypertrophy, a response of the heart to increased workload, a cardiac insult such as a heart attack or genetic mutation. Cardiac hypertrophy is usually characterized by an increase in cardiomyocyte size and thickening of ventricular walls. Initially, such growth is an adaptive response to maintain cardiac function; however, in settings of sustained stress and as time progresses, these changes become maladaptive and the heart ultimately fails. In this review, we discuss the key features of pathological cardiac hypertrophy and the numerous mediators that have been found to be involved in the pathogenesis of cardiac hypertrophy affecting gene transcription, calcium handling, protein synthesis, metabolism, autophagy, oxidative stress and inflammation. We also discuss new mediators including signaling proteins, microRNAs, long noncoding RNAs and new findings related to the role of calcineurin and calcium-/calmodulin-dependent protein kinases. We also highlight mediators and processes which contribute to the transition from adaptive cardiac remodeling to maladaptive remodeling and heart failure. Treatment strategies for heart failure commonly include diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers and β-blockers; however, mortality rates remain high. Here, we discuss new therapeutic approaches (e.g., RNA-based therapies, dietary supplementation, small molecules) either entering clinical trials or in preclinical development. Finally, we address the challenges that remain in translating these discoveries to new and approved therapies for heart failure.
Kobara, Miyuki; Furumori-Yukiya, Akiko; Kitamura, Miho; Matsumura, Mihoko; Ohigashi, Makoto; Toba, Hiroe; Nakata, Tetsuo
2015-08-01
Caloric restriction (CR) prevents senescent changes, in which reactive oxygen species (ROS) have a critical role. Left ventricular (LV) hypertrophy is a risk factor for cardiovascular diseases. We examined whether CR alters cardiac redox state and hypertrophy from chronic pressure overload. Male c57BL6 mice were subjected to ascending aortic constriction (AAC) with ad libitum caloric intake (AL + AAC group) or 40% restricted caloric intake (CR + AAC group). CR was initiated 2 weeks before AAC and was continued for 4 weeks. Two weeks after constriction, AAC increased LV wall thickness, impaired transmitral flow velocity, and augmented myocyte hypertrophy and fibrosis, in association with enhancement of BNP and collagen III expressions in the AL + AAC group. In the AL + AAC group, oxidative stress in cardiac tissue and mitochondria were enhanced, and NADPH oxidase activity and mitochondrial ROS production were elevated. These changes were significantly attenuated in the CR + AAC group. Additionally, in antioxidant systems, myocardial glutathione peroxidase and superoxide dismutase activities were enhanced in the CR + AAC group. Chronic pressure overload increased cardiac oxidative damage, in association with cardiac hypertrophy and fibrosis. Short-term CR suppressed oxidative stress and improved cardiac function, suggesting that short-term CR could be a useful strategy to prevent pressure overload-induced cardiac injury. Copyright © 2015 Elsevier Inc. All rights reserved.
Hirotani, Shinichi; Higuchi, Yoshiharu; Nishida, Kazuhiko; Nakayama, Hiroyuki; Yamaguchi, Osamu; Hikoso, Shungo; Takeda, Toshihiro; Kashiwase, Kazunori; Watanabe, Tetsuya; Asahi, Michio; Taniike, Masayuki; Tsujimoto, Ikuko; Matsumura, Yasushi; Sasaki, Terukatsu; Hori, Masatsugu; Otsu, Kinya
2004-06-01
G-protein-coupled receptor agonists including endothelin-1 (ET-1) and phenylephrine (PE) induce hypertrophy in neonatal ventricular cardiomyocytes. Others and we previously reported that Rac1 signaling pathway plays an important role in this agonist-induced cardiomyocyte hypertrophy. In this study reported here, we found that a Ca(2+)-sensitive non-receptor tyrosine kinase, proline-rich tyrosine kinase 2 (Pyk2)/cell adhesion kinase beta (CAKbeta), is involved in ET-1- and PE-induced cardiomyocyte hypertrophy medicated through Rac1 activation. ET-1, PE or the Ca(2+) inophore, ionomycin, stimulated a rapid increase in tyrosine phosphorylation of Pyk2. The tyrosine phosphorylation of Pyk2 was suppressed by the Ca(2+) chelator, BAPTA. ET-1- or PE-induced increases in [(3)H]-leucine incorporation and expression of atrial natriuretic factor and the enhancement of sarcomere organization. Infection of cardiomyocytes with an adenovirus expressing a mutant Pyk2 which lacked its kinase domain or its ability to bind to c-Src, eliminated ET-1- and PE-induced hypertrophic responses. Inhibition of Pyk2 activation also suppressed Rac1 activation and reactive oxygen species (ROS) production. These findings suggest that the signal transduction pathway leading to hypertrophy involves Ca(2+)-induced Pyk2 activation followed by Rac1-dependent ROS production.
VO(2peak), myocardial hypertrophy, and myocardial blood flow in endurance-trained men.
Laaksonen, Marko S; Heinonen, Ilkka; Luotolahti, Matti; Knuuti, Juhani; Kalliokoski, Kari K
2014-08-01
Endurance training induces cardiovascular and metabolic adaptations, leading to enhanced endurance capacity and exercise performance. Previous human studies have shown contradictory results in functional myocardial vascular adaptations to exercise training, and we hypothesized that this may be related to different degrees of hypertrophy in the trained heart. We studied the interrelationships between peak aerobic power (V˙O2peak), myocardial blood flow (MBF) at rest and during adenosine-induced vasodilation, and parameters of myocardial hypertrophy in endurance-trained (ET, n = 31) and untrained (n = 17) subjects. MBF and myocardial hypertrophy were studied using positron emission tomography and echocardiography, respectively. Both V˙O2peak (P < 0.001) and left ventricular (LV) mass index (P < 0.001) were higher in the ET group. Basal MBF was similar between the groups. MBF during adenosine was significantly lower in the ET group (2.88 ± 1.01 vs 3.64 ± 1.11 mL·g·min, P < 0.05) but not when the difference in LV mass was taken into account. V˙O2peak correlated negatively with adenosine-stimulated MBF, but when LV mass was taken into account as a partial correlate, this correlation disappeared. The present results show that increased LV mass in ET subjects explains the reduced hyperemic myocardial perfusion in this subject population and suggests that excessive LV hypertrophy has negative effect on cardiac blood flow capacity.
Park, Chul Hwan; Chung, Hyemoon; Kim, Yoonjung; Kim, Jong-Youn; Min, Pil-Ki; Lee, Kyung-A; Yoon, Young Won; Kim, Tae Hoon; Lee, Byoung Kwon; Hong, Bum-Kee; Rim, Se-Joong; Kwon, Hyuck Moon; Choi, Eui-Young
2018-05-04
Although, cardiac magnetic resonance imaging (CMR) is a gold standard for risk stratification of hypertrophic cardiomyopathy (HCM), is limited in some situations. We sought to evaluate the predictive power of quantitative electrocardiography in assessing hypertrophy pattern and fibrosis in HCM. Eighty-eight patients with HCM were studied. Voltage of R-S-T waves, number of fragmented QRS (fQRS) complexes, and T wave morphology were measured by 12-lead electrocardiography. Sixteen segmental thickness, late gadolinium enhancement (LGE), native T1, extracellular volume fraction (ECV), and T2, left ventricular (LV) mass and %LGE were measured by CMR. Patterns of LV hypertrophy were classified as pure apical, mixed, or asymmetrical septal hypertrophy. Positive and negative predictive values of biphasic T wave for pure apical type were 70.4 and 63.9%, and the predictive values of precordial negative T wave sums [Formula: see text] 12.5 mm were 69.2 and 79.6%. Precordial S waves, especially Cornell voltage index, were significantly correlated to LV mass index and maximal thickness (p [Formula: see text]0.001). The number of fQRS leads was significantly correlated to %LGE, average ECV, and T2 (all p [Formula: see text]0.001). More than one lead with fQRS could predict [Formula: see text]5% of LGE mass with 58% sensitivity and 63% specificity (p = 0.049, area under the curve = 0.627). However, degree of correlation between maximal thickness and precordial S was poor in cases with fQRS more two leads. T wave morphology and precordial S helps discriminate hypertrophy pattern and maximal hypertrophy, however, in cases with more than two leads of concomitant fQRS, CMR defines fibrosis amount and hypertrophy more accurately.
Axelsson, Anna; Iversen, Kasper; Vejlstrup, Niels; Ho, Carolyn; Norsk, Jakob; Langhoff, Lasse; Ahtarovski, Kiril; Corell, Pernille; Havndrup, Ole; Jensen, Morten; Bundgaard, Henning
2015-02-01
No medical treatment has been reliably shown to halt or reverse disease progression in hypertrophic cardiomyopathy, but the results of several pilot studies have suggested beneficial effects of angiotensin II receptor blockers on left ventricular hypertrophy and fibrosis, which are predictive of an adverse outcome. We aimed to assess the effect of the angiotensin II receptor blocker losartan on left ventricular hypertrophy and fibrosis in patients with hypertrophic cardiomyopathy. In this single-centre, randomised, double-blind, placebo-controlled trial, adult patients (aged 18 years and older) with obstructive or non-obstructive hypertrophic cardiomyopathy were randomly assigned via computer-based system to losartan (100 mg per day) or placebo for 12 months. Patients and investigators were masked to assigned treatment. The primary endpoint was change in left ventricular mass as assessed by cardiac magnetic resonance imaging (CMR) or CT. Efficacy analyses were done in the modified intention-to-treat population (all patients with data available at the 12-month follow-up). The trial is registered with ClinicalTrials.gov, number NCT01447654. Between Dec 1, 2011, and May 1, 2013, 318 patients were screened. 133 patients (mean age 52 years [SD 13], 35% women) consented and were randomly assigned to placebo (n=69) or losartan (n=64). 124 (93%) patients completed the study and were included in the modified intention-to-treat analysis for the primary endpoint. After 12 months we noted no significant difference in the change in left ventricular mass between the placebo group and the losartan group (mean difference 1 g/m(2), 95% CI -3 to 6; p=0·60). A decrease in systolic blood pressure in the losartan group (from mean 127 mm Hg [SD 12] to 121 mm Hg [14]; p=0·0001) confirmed drug compliance; blood pressure did not decrease in the placebo group. Two (2%) patients, both in the placebo group, died from sudden cardiac death during follow-up. In the losartan group, one (1%) patient had angioedema, one (1%) had deterioration of renal function, and one (1%) had hyperkalaemia. Treatment was well tolerated by patients with left ventricular outflow obstruction at baseline. Our findings challenge the generally held view that angiotensin II receptor blockers reduce cardiac hypertrophy. Treatment with losartan was safe, suggesting that it can be used for other indications in patients with hypertrophic cardiomyopathy, irrespective of obstructive physiology. Additional studies are needed to assess the effect of angiotensin II receptor blockers in preclinical hypertrophic cardiomyopathy-eg, in genotype-positive but phenotype-negative individuals. Copyright © 2015 Elsevier Ltd. All rights reserved.
Forfar, J C; Matthews, D M; Toft, A D
1984-01-01
Sequential measurements of systolic time intervals, left ventricular dimensions, and the derived indices of contractility were undertaken at rest and during isometric exercise in 15 hyperthyroid patients before, during, and after antithyroid treatment. At rest hyperthyroidism was characterised by a shortened pre-ejection period and increased velocity of circumferential shortening of the left ventricle. During isometric exercise, however, the pre-ejection period increased significantly beyond that predicted for normal subjects, and the velocity of circumferential fibre shortening fell by 30%. In contrast, both the pre-ejection period and the velocity of circumferential fibre shortening were unchanged during exercise after a stable euthyroid state had been achieved for at least three months. Comparison between exercise responses and thyroid status during antithyroid treatment showed that a biochemical euthyroid state may be achieved many weeks before normalisation of contractile response to exercise. These findings support the hypothesis of reversible depression of left ventricular function in hyperthyroidism. Responses at rest principally reflect the peripheral actions of thyroid hormone excess. PMID:6743439
[Evaluation of myocardial uptake of beta-methyl-(123I)-iodophenylpentadecanoic acid (123I-BMIPP)].
Momose, M; Kobayashi, H; Saito, K; Matsumoto, N; Maki, M; Hosoda, S; Kusakabe, K
1994-12-01
To evaluate the myocardial uptake of beta-methyl-(123I)-iodophenylpentadecanoic acid (123I-BMIPP), nineteen patients with ischemic heart disease including left ventricular hypertrophy (mean age 63 +/- 7.8, 14 males and 5 females) underwent BMIPP myocardial scintigraphy. Myocardial uptake (MU) of BMIPP to the total injected dose was calculated from anterior view of the planar image in all subjects, and was compared with plasma glucose (BS), triglyceride (TG), and free fatty acid (FFA). It was also compared with left ventricular mass (LVM) calculated with echocardiography. MU was not related to BS, TG, and FFA, however had the positive correlation with LVM (r = 0.676, p < 0.01). Myocardial uptake per left ventricular mass (MU/LVM) had the negative correlation with LVM (r = -0.671, p < 0.01). Further studies for the significance of MU/LVM will be required.
Whitaker, Morgan E; Nair, Vineet; Sinari, Shripad; Dherange, Parinita A; Natarajan, Balaji; Trutter, Lindsey; Brittain, Evan L; Hemnes, Anna R; Austin, Eric D; Patel, Kumar; Black, Stephen M; Garcia, Joe G N; Yuan Md PhD, Jason X; Vanderpool, Rebecca R; Rischard, Franz; Makino, Ayako; Bedrick, Edward J; Desai, Ankit A
2018-06-01
Diabetes mellitus is associated with left ventricular hypertrophy and dysfunction. Parallel studies have also reported associations between diabetes mellitus and right ventricular dysfunction and reduced survival in patients with pulmonary arterial hypertension. However, the impact of diabetes mellitus on the pulmonary vasculature has not been well characterized. We hypothesized that diabetes mellitus and hyperglycemia could specifically influence right ventricular afterload and remodeling in patients with Group I pulmonary arterial hypertension, providing a link to their known susceptibility to right ventricular dysfunction. Using an adjusted model for age, sex, pulmonary vascular resistance, and medication use, associations of fasting blood glucose, glycated hemoglobin, and the presence of diabetes mellitus were evaluated with markers of disease severity in 162 patients with pulmonary arterial hypertension. A surrogate measure of increased pulmonary artery stiffness, elevated pulmonary arterial elastance (P = .012), along with reduced log(pulmonary artery capacitance) (P = .006) were significantly associated with the presence of diabetes mellitus in patients with pulmonary arterial hypertension in a fully adjusted model. Similar associations between pulmonary arterial elastance and capacitance were noted with both fasting blood glucose and glycated hemoglobin. Furthermore, right ventricular wall thickness on echocardiography was greater in pulmonary arterial hypertension patients with diabetes, supporting the link between right ventricular remodeling and diabetes. Cumulatively, these data demonstrate that an increase in right ventricular afterload, beyond pulmonary vascular resistance alone, may influence right ventricular remodeling and provide a mechanistic link between the susceptibility to right ventricular dysfunction in patients with both diabetes mellitus and pulmonary arterial hypertension. Copyright © 2018 Elsevier Inc. All rights reserved.
Doppler echocardiographic analysis of left ventricular filling in treated hypertensive patients.
Phillips, R A; Coplan, N L; Krakoff, L R; Yeager, K; Ross, R S; Gorlin, R; Goldman, M E
1987-02-01
Early detection and prevention of cardiac dysfunction is an important goal in the management of hypertensive patients. In this study, Doppler echocardiography was used to evaluate the pattern of left ventricular diastolic filling in 38 subjects: 18 treated hypertensive patients (blood pressure 141 +/- 17/83 +/- 10 mm Hg, mean +/- SD) without other coronary risk factors and 20 risk-free normotensive subjects of similar age (47 +/- 10 and 49 +/- 13 years, respectively). Peak velocity of late left ventricular filling due to the atrial contraction was greater in hypertensive compared with normotensive subjects (69 +/- 14 versus 52 +/- 13 cm/s; p less than 0.001). Peak velocity of late filling was significantly greater in hypertensive versus normotensive subjects in those aged 50 years or younger and those older than age 50 (65 +/- 12 versus 50 +/- 11; p less than 0.01 and 75 +/- 15 versus 56 +/- 15 cm/s; p less than 0.05, respectively). In hypertensive subjects, peak velocity of late filling did not correlate with routine indexes of hypertensive heart disease (including posterior wall thickness and left ventricular mass), systolic and diastolic blood pressure or duration of hypertension. These results indicate that increased velocity of late left ventricular filling may be independent of left ventricular hypertrophy and persist despite effective blood pressure control.
Clemente, Carolina F M Z; Tornatore, Thais F; Theizen, Thais H; Deckmann, Ana C; Pereira, Tiago C; Lopes-Cendes, Iscia; Souza, José Roberto M; Franchini, Kleber G
2007-12-07
Hypertrophy is a critical event in the onset of failure in chronically overloaded hearts. Focal adhesion kinase (FAK) has attracted particular attention as a mediator of hypertrophy induced by increased load. Here, we demonstrate increased expression and phosphorylation of FAK in the hypertrophic left ventricles (LVs) of aortic-banded mice. We used an RNA interference strategy to examine whether FAK signaling plays a role in the pathophysiology of load-induced LV hypertrophy and failure. Intrajugular delivery of specific small interfering RNA induced prolonged FAK silencing ( approximately 70%) in both normal and hypertrophic LVs. Myocardial FAK silencing was accompanied by prevention, as well as reversal, of load-induced left ventricular hypertrophy. The function of LVs was preserved and the survival rate was higher in banded mice treated with small interfering RNA targeted to FAK, despite the persistent pressure overload. Studies in cardiac myocytes and fibroblasts harvested from LVs confirmed the ability of the systemically administered specific small interfering RNA to silence FAK in both cell types. Further analysis indicated attenuation of cardiac myocyte hypertrophic growth and of the rise in the expression of beta-myosin heavy chain in overloaded LVs. Moreover, FAK silencing was demonstrated to attenuate the rise in the fibrosis, collagen content, and activity of matrix metalloproteinase-2 in overloaded LVs, as well as the rise of matrix metalloproteinase-2 protein expression in fibroblasts harvested from overloaded LVs. This study provides novel evidence that FAK may be involved in multiple aspects of the pathophysiology of cardiac hypertrophy and failure induced by pressure overload.
Khairallah, Ramzi J.; O'Shea, Karen M.; Brown, Bethany H.; Khanna, Nishanth; Des Rosiers, Christine
2010-01-01
Intake of fish oil containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) prevents heart failure; however, the mechanisms are unclear. Mitochondrial permeability transition pore (MPTP) opening contributes to myocardial pathology in cardiac hypertrophy and heart failure, and treatment with DHA + EPA delays MPTP opening. Here, we assessed: 1) whether supplementation with both DHA and EPA is needed for optimal prevention of MPTP opening, and 2) whether this benefit occurs in hypertrophied myocardium. Rats with either normal myocardium or cardiac hypertrophy induced by 8 weeks of abdominal aortic banding were fed one of four diets: control diet without DHA or EPA or diets enriched with either DHA, EPA, or DHA + EPA (1:1 ratio) at 2.5% of energy intake for 17 weeks. Aortic banding caused a 27% increase in left ventricular mass and 25% depletion in DHA in mitochondrial phosopholipids in rats fed the control diet. DHA supplementation raised DHA in phospholipids ∼2-fold in both normal and hypertrophied hearts and increased EPA. DHA + EPA supplementation also increased DHA, but to a lesser extent than DHA alone. EPA supplementation increased EPA, but did not affect DHA compared with the control diet. Ca2+-induced MPTP opening was delayed by DHA and DHA + EPA supplementation in both normal and hypertrophied hearts, but EPA had no effect on MPTP opening. These results show that supplementation with DHA alone effectively increases both DHA and EPA in cardiac mitochondrial phospholipids and delays MPTP and suggest that treatment with DHA + EPA offers no advantage over DHA alone. PMID:20624993
Obese subjects show sex-specific differences in right ventricular hypertrophy.
Rider, Oliver J; Lewis, Andrew J M; Lewandowski, Adam J; Ntusi, Ntobeko; Nethononda, Richard; Petersen, Steffen E; Francis, Jane M; Pitcher, Alex; Banerjee, Rajarshi; Leeson, Paul; Neubauer, Stefan
2015-01-01
As right ventricular (RV) remodeling in obesity remains underinvestigated, and the impact of left ventricular (LV) diastolic dysfunction on RV hypertrophy is unknown, we aimed to investigate whether (1) sex-specific patterns of RV remodeling exist in obesity and (2) LV diastolic dysfunction in obesity is related to RV hypertrophy. Seven hundred thirty-nine subjects (women, n=345; men, n=394) without identifiable cardiovascular risk factors (body mass index [BMI], 15.3-59.2 kg/m2) underwent cardiovascular magnetic resonance (1.5 T) to measure RV mass (g), RV end-diastolic volume (mL), RV mass/volume ratio, and LV diastolic peak filling rate (mL/s). All subjects were normotensive (average, 119±11/73±8 mm Hg), normoglycaemic (4.8±0.5 mmol/L), and normocholesterolaemic (4.8±0.9 mmol/L) at the time of scanning. Across both sexes, there was a moderately strong positive correlation between BMI and RV mass (men, +0.8 g per BMI point increase; women, +1.0 g per BMI point increase; both P<0.001). Whereas women exhibited RV cavity dilatation (RV end-diastolic volume, +1.0 mL per BMI point increase; P<0.001), BMI was not correlated with RV end-diastolic volume in men (R=0.04; P=0.51). Concentric RV remodeling was present in both sexes, with RV mass/volume ratio being positively correlated to BMI (men, R=0.41; women, R=0.51; both P<0.001). Irrespective of sex, the LV peak filling rate was negatively correlated with both RV mass (men, R=-0.43; women, R=-0.44; both P<0.001) and RV mass/volume ratio (men, R=-0.37; women, R=-0.35; both P<0.001). A sex difference in RV remodeling exists in obesity. Whereas men exhibit concentric RV remodeling, women exhibit a mixed pattern of eccentric and concentric remodeling. Regardless of sex, reduced LV diastolic function is associated with concentric RV remodeling. © 2014 American Heart Association, Inc.
Myburgh, Catharina Elizabeth; Malan, Leoné; Wentzel, Annemarie; Scheepers, Jacobus De Wet; Malan, Nicolaas Theodor
2018-05-31
Defensive coping (DefS) was associated with cardiovascular disease (CVD) susceptibility in Blacks. Whether coping strategies will associate with sub-clinical left ventricular hypertrophy (electrocardiographic-left ventricular hypertrophy [ECG-LVH] or Cornell product), cardiomyocyte injury and blood pressure (BP), is unclear. Therefore, we assessed relationships between ECG-LVH, cardiac troponin T (cTnT) and 24-hour BP in bi-ethnic groups when habitually utilising a certain coping style, and these groups when having a stress-related cTnT cut-point of 4.2ng/L. A target population study included a Black (n=190) and White (n=204) teachers' gender cohort (20-65years) from South Africa. The Coping Strategy Indicator determined DefS, social support and avoidance coping scores. Fasting blood samples, 10-lead ECG, 24-hour BP and -ECG data were obtained. Interaction effects showed no gender, social support and avoidance coping differences. Stratification of groups was done for ethnicity and DefS. Blacks sought more social support, used less avoidance coping and presented with higher CVD susceptibility. Hypertension prevalence and ECG-LVH levels in DefS Blacks (63%) were higher compared to DefS Whites (40%). Multivariate regression analyses showed positive associations between Cornell product, cTnT and BP [p≤0.05] in DefS Blacks only. Their 24-hour systolic blood pressure (SBP) was associated with time-domain depressed heart-rate-variability and prolonged ST-segment-depression especially when applying an established stress-related cTnT ≥ 4.2ng/L cut-point. Defensive coping facilitated autonomic hyperactivity, myocardial injury and subsequent compensatory BP elevations as possible homeostatic reflexes to alleviate myocardial perfusion deficits. The resulting pressure overload increased sub-clinical wall remodelling and ischaemic heart disease risk in Blacks utilising habitual defensiveness. We therefore recommend regular ECG and high sensitivity cTnT screening in asymptomatic patients with emotional stress susceptibility. Longitudinal evidence is needed to confirm causality and progression of cardiomyopathy risk. Copyright © 2018 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
Interleukin-6 Mediates Myocardial Fibrosis, Concentric Hypertrophy and Diastolic Dysfunction in Rats
Meléndez, Giselle C.; McLarty, Jennifer L.; Levick, Scott P.; Du, Yan; Janicki, Joseph S.; Brower, Gregory L.
2010-01-01
While there is a correlation between hypertension and levels of IL-6, the exact role of this cytokine in myocardial remodeling is unknown. This is complicated by the variable tissue and circulating levels of IL-6 reported in numerous experimental models of hypertension. Accordingly, we explored the hypothesis that elevated levels of IL-6 mediate adverse myocardial remodeling. To this end, adult male Sprague Dawley rats were infused with IL-6 (2.5 μg·kg-1·hr-1, IP) for 7 days via osmotic minipump and compared to vehicle infused aged-matched controls. Left ventricular function was evaluated using a blood-perfused isolated heart preparation. In addition, myocardial interstitial collagen volume fraction and isolated cardiomyocyte size were also assessed. Isolated adult cardiac fibroblast experiments were performed to determine the importance of the soluble IL-6 receptor in mediating cardiac fibrosis. IL-6 infusions in vivo resulted in concentric left ventricular hypertrophy, increased ventricular stiffness, a marked increase in collagen volume fraction (6.2 vs. 1.7%; p < 0.001), and proportional increases in cardiomyocyte width and length; all independent of blood pressure. The soluble IL-6 receptor in combination with IL-6 was found to be essential in increasing collagen content regulated by isolated cardiac fibroblasts, and also played a role in mediating a phenotypic conversion to myofibroblasts. These novel observations demonstrate that IL-6 induces a myocardial phenotype almost identical to that of the hypertensive heart, identifying IL-6 as potentially important in this remodeling process. PMID:20606113
Cardiac abnormalities in patients with mitochondrial DNA mutation 3243A>G.
Majamaa-Voltti, Kirsi; Peuhkurinen, Keijo; Kortelainen, Marja-Leena; Hassinen, Ilmo E; Majamaa, Kari
2002-08-01
Tissues that depend on aerobic energy metabolism suffer most in diseases caused by mutations in mitochondrial DNA (mtDNA). Cardiac abnormalities have been described in many cases, but their frequency and clinical spectrum among patients with mtDNA mutations is unknown. Thirty-nine patients with the 3243A>G mtDNA mutation were examined, methods used included clinical evaluation, electrocardiogram, Holter recording and echocardiography. Autopsy reports on 17 deceased subjects were also reviewed. The degree of 3243A>G mutation heteroplasmy was determined using an Apa I restriction fragment analysis. Better hearing level (BEHL0.5-4 kHz) was used as a measure of the clinical severity of disease. Left ventricular hypertrophy (LVH) was diagnosed in 19 patients (56%) by echocardiography and in six controls (15%) giving an odds ratio of 7.5 (95% confidence interval; 1.74-67). The dimensions of the left ventricle suggested a concentric hypertrophy. Left ventricular systolic or diastolic dysfunction was observed in 11 patients. Holter recording revealed frequent ventricular extrasystoles (>10/h) in five patients. Patients with LVH differed significantly from those without LVH in BEHL0.5-4 kHz, whereas the contribution of age or the degree of the mutant heteroplasmy in skeletal muscle to the risk of LVH was less remarkable. Structural and functional abnormalities of the heart were common in patients with 3243A>G. The risk of LVH was related to the clinical severity of the phenotype, and to a lesser degree to age, suggesting that patients presenting with any symptoms from the mutation should also be evaluated for cardiac abnormalities.
Su, Ho-Ming; Lin, Tsung-Hsien; Hsu, Po-Chao; Chu, Chun-Yuan; Lee, Wen-Hsien; Chen, Szu-Chia; Lee, Chee-Siong; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung
2012-01-01
An interarm systolic blood pressure (SBP) difference of 10 mmHg or more have been associated with peripheral artery disease and adverse cardiovascular outcomes. We investigated whether an association exists between this difference and ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and echocardiographic parameters. A total of 1120 patients were included in the study. The bilateral arm blood pressures were measured simultaneously by an ABI-form device. The values of ABI and baPWV were also obtained from the same device. Clinical data, ABI<0.9, baPWV, echocariographic parameters, and an interarm SBP difference ≥10 mmHg were compared and analyzed. We performed two multivariate forward analyses for determining the factors associated with an interarm SBP difference ≥10 mmHg [model 1: significant variables in univariate analysis except left ventricular mass index (LVMI); model 2: significant variables in univariate analysis except ABI<0.9 and baPWV]. The ABI<0.9 and high baPWV in model 1 and high LVMI in model 2 were independently associated with an interarm SBP difference ≥10 mmHg. Female, hypertension, and high body mass index were also associated with an interarm SBP difference ≥10 mmHg. Our study demonstrated that ABI<0.9, high baPWV, and high LVMI were independently associated with an interarm SBP difference of 10 mmHg or more. Detection of an interarm SBP difference may provide a simple method of detecting patients at increased risk of atherosclerosis and left ventricular hypertrophy. PMID:22927905
Matrix elasticity regulates the optimal cardiac myocyte shape for contractility
McCain, Megan L.; Yuan, Hongyan; Pasqualini, Francesco S.; Campbell, Patrick H.
2014-01-01
Concentric hypertrophy is characterized by ventricular wall thickening, fibrosis, and decreased myocyte length-to-width aspect ratio. Ventricular thickening is considered compensatory because it reduces wall stress, but the functional consequences of cell shape remodeling in this pathological setting are unknown. We hypothesized that decreases in myocyte aspect ratio allow myocytes to maximize contractility when the extracellular matrix becomes stiffer due to conditions such as fibrosis. To test this, we engineered neonatal rat ventricular myocytes into rectangles mimicking the 2-D profiles of healthy and hypertrophied myocytes on hydrogels with moderate (13 kPa) and high (90 kPa) elastic moduli. Actin alignment was unaffected by matrix elasticity, but sarcomere content was typically higher on stiff gels. Microtubule polymerization was higher on stiff gels, implying increased intracellular elastic modulus. On moderate gels, myocytes with moderate aspect ratios (∼7:1) generated the most peak systolic work compared with other cell shapes. However, on stiffer gels, low aspect ratios (∼2:1) generated the most peak systolic work. To compare the relative contributions of intracellular vs. extracellular elasticity to contractility, we developed an analytical model and used our experimental data to fit unknown parameters. Our model predicted that matrix elasticity dominates over intracellular elasticity, suggesting that the extracellular matrix may potentially be a more effective therapeutic target than microtubules. Our data and model suggest that myocytes with lower aspect ratios have a functional advantage when the elasticity of the extracellular matrix decreases due to conditions such as fibrosis, highlighting the role of the extracellular matrix in cardiac disease. PMID:24682394
Kaneto, C.M.; Nascimento, J.S.; Moreira, M.C.R.; Ludovico, N.D.; Santana, A.P.; Silva, R.A.A.; Silva-Jardim, I.; Santos, J.L.; Sousa, S.M.B.; Lima, P.S.P.
2017-01-01
Recent evidence suggests that cell-derived circulating miRNAs may serve as biomarkers of cardiovascular diseases. However, a few studies have investigated the potential of circulating miRNAs as biomarkers for left ventricular hypertrophy (LVH). In this study, we aimed to characterize the miRNA profiles that could distinguish hypertensive patients with LHV, hypertensive patients without LVH and control subjects, and identify potential miRNAs as biomarkers of LVH. LVH was defined by left ventricular mass indexed to body surface area >125 g/m2 in men and >110 g/m2 in women and patients were classified as hypertensive when presenting a systolic blood pressure of 140 mmHg or more, or a diastolic blood pressure of 90 mmHg or more. We employed miRNA PCR array to screen serum miRNAs profiles of patients with LVH, essential hypertension and healthy subjects. We identified 75 differentially expressed miRNAs, including 49 upregulated miRNAs and 26 downregulated miRNAs between LVH and control patients. We chose 2 miRNAs with significant differences for further testing in 59 patients. RT-PCR analysis of serum samples confirmed that miR-7-5p and miR-26b-5p were upregulated in the serum of LVH hypertensive patients compared with healthy subjects. Our findings suggest that these miRNAs may play a role in the pathogenesis of hypertensive LVH and may represent novel biomarkers for this disease. PMID:29069223
Minamisawa, S; Gu, Y; Ross, J; Chien, K R; Chen, J
1999-04-09
Our previous study of homozygous mutants of the ventricular specific isoform of myosin light chain 2 (mlc-2v) demonstrated that mlc-2v plays an essential role in murine heart development (Chen, J., Kubalak, S. W., Minamisawa, S., Price, R. L., Becker, K. D., Hickey, R., Ross, J., Jr., and Chien, K. R. (1998) J. Biol. Chem. 273, 1252-1256). As gene dosage of some myofibrillar proteins can affect muscle function, we have analyzed heterozygous mutants in depth. Ventricles of heterozygous mutants displayed a 50% reduction in mlc-2v mRNA, yet expressed normal levels of protein both under basal conditions and following induction of cardiac hypertrophy by aortic constriction. Heterozygous mutants exhibited cardiac function comparable to that of wild-type littermate controls both prior to and following aortic constriction. There were no significant differences in contractility and responses to calcium between wild-type and heterozygous unloaded cardiomyocytes. We conclude that heterozygous mutants show neither a molecular nor a physiological cardiac phenotype either at base line or following hypertrophic stimuli. These results suggest that post-transcriptional compensatory mechanisms play a major role in maintaining the level of MLC-2v protein in murine hearts. In addition, as our mlc-2v knockout mutants were created by a knock-in of Cre recombinase into the endogenous mlc-2v locus, this study demonstrates that heterozygous mlc-2v cre knock-in mice are appropriate for ventricular specific gene targeting.
Maayah, Zaid H; Althurwi, Hassan N; El-Sherbeni, Ahmed A; Abdelhamid, Ghada; Siraki, Arno G; El-Kadi, Ayman O S
2017-05-01
Numerous experimental studies have demonstrated the role of cytochrome P450 1B1 (CYP1B1) and its associated mid-chain hydroxyeicosatetraenoic acids (mid-chain HETEs) metabolite in the pathogenesis of cardiac hypertrophy. However, the ability of isoproterenol (ISO) to induce cardiac hypertrophy through mid-chain HETEs has not been investigated yet. Therefore, we hypothesized that ISO induces cardiac hypertrophy through the induction of CYP1B1 and its associated mid-chain HETE metabolites. To test our hypothesis, Sprague-Dawley rats were treated with ISO (5 mg/kg i.p.) for 12 and 72 h whereas, human ventricular cardiomyocytes RL-14 cells were exposed to 100 μM ISO in the presence and absence of 0.5 μM tetramethoxystilbene (TMS) a selective CYP1B1 inhibitor, or 25 nM CYP1B1-siRNA. Moreover, RL-14 cells were transiently transfected with the CRISPR-CYP1B1 plasmid. Thereafter, real-time PCR, western blot analysis, and liquid chromatography-electrospray ionization mass spectroscopy were used to determine the level of gene expression, protein expression, and mid-chain HETEs, respectively. Our results showed that ISO induced CYP1B1 protein expression and the level of cardiac mid-chain HETEs in vivo at pre-hypertrophic and hypertrophic stage. In vitro, inhibition of CYP1B1 using TMS or CYP1B1-siRNA significantly attenuates ISO-induced hypertrophy. Furthermore, overexpression of CYP1B1 significantly induced cellular hypertrophy and mid-chain HETEs metabolite. Mechanistically, the protective effect of TMS against cardiac hypertrophy was mediated through the modulation of superoxide anion, mitogen-activated protein kinases (MAPKs), and nuclear factor-κB (NF-κB). In conclusion, our study provides the first evidence that CYP1B1 and its associated mid-chain HETE metabolites are directly involved in the ISO-induced cardiac hypertrophy.
Association of Cardiac Troponin T With Left Ventricular Structure and Function in CKD
Mishra, Rakesh K.; Li, Yongmei; DeFilippi, Christopher; Fischer, Michael J.; Yang, Wei; Keane, Martin; Chen, Jing; He, Jiang; Kallem, Radhakrishna; Horwitz, Ed; Rafey, Mohammad; Raj, Dominic S.; Go, Alan S.; Shlipak, Michael G.
2013-01-01
Background Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT with cardiac structural and functional abnormalities in a cohort of chronic kidney disease (CKD) patients without heart failure. Study Design Cross-sectional. Setting & Participants Chronic Renal Insufficiency Cohort (CRIC; N= 3,243) Predictor The primary predictor was cTnT. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein, and estimated glomerular filtration rate using cystatin C. Outcomes Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function. Measurements Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT with each echocardiographic outcome. Results cTnT was detectable in 2,735 (84%) persons; the median was 13.3 (IQR, 7.7–23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9 – 738.7 pg/mL) was associated with approximately two times as likely to experience LV hypertrophy (OR, 2.43; 95% CI, 1.44–4.09) in the fully adjusted model. cTnT had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.1–1.7] per 1-log unit; p<0.01). There was no significant independent association between cTnT and LV diastolic dysfunction. When evaluated as a screening test, cTnT functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both) with weaker areas under the curve for the other outcomes. Limitations The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study. Conclusions In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in CKD are predominantly an indicator of pathological LV hypertrophy. PMID:23291148
Association of cardiac troponin T with left ventricular structure and function in CKD.
Mishra, Rakesh K; Li, Yongmei; DeFilippi, Christopher; Fischer, Michael J; Yang, Wei; Keane, Martin; Chen, Jing; He, Jiang; Kallem, Radhakrishna; Horwitz, Edward J; Rafey, Mohammad; Raj, Dominic S; Go, Alan S; Shlipak, Michael G
2013-05-01
Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT levels with cardiac structural and functional abnormalities in a cohort of patients with chronic kidney disease (CKD) without heart failure. Cross-sectional. Chronic Renal Insufficiency Cohort (CRIC; N=3,243). The primary predictor was cTnT level. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein level, and estimated glomerular filtration rate using cystatin C. Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function. Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT level with each echocardiographic outcome. cTnT was detectable in 2,735 (84%) persons; median level was 13.3 (IQR, 7.7-23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9-738.7 pg/mL) was approximately 2 times as likely to have LV hypertrophy (OR, 2.43; 95% CI, 1.44-4.09) in the fully adjusted model. cTnT level had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.2-1.7] per 1-log unit; P < 0.001). There was no significant independent association between cTnT level and LV diastolic dysfunction. When evaluated as a screening test, cTnT level functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both), with weaker areas under the curve for the other outcomes. The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study. In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in patients with CKD are predominantly an indicator of pathologic LV hypertrophy. Published by Elsevier Inc.
Solomon, Scott D; Appelbaum, Evan; Manning, Warren J; Verma, Anil; Berglund, Tommy; Lukashevich, Valentina; Cherif Papst, Cheraz; Smith, Beverly A; Dahlöf, Björn
2009-02-03
Left ventricular (LV) hypertrophy, a marker of cardiac end-organ damage, is associated with an increased risk of cardiovascular morbidity and mortality. Inhibitors of the renin-angiotensin-aldosterone system may reduce LV mass to a greater extent than other antihypertensive agents. We compared the effect of aliskiren, the first orally active direct renin inhibitor, the angiotensin-receptor blocker losartan, and their combination on the reduction of LV mass in hypertensive patients. We randomized 465 patients with hypertension, increased ventricular wall thickness, and body mass index >25 kg/m(2) to receive aliskiren 300 mg, losartan 100 mg, or their combination daily for 9 months. Patients were treated to standard blood pressure targets with add-on therapy, excluding other inhibitors of the renin-angiotensin-aldosterone system and beta-blockers. Patients underwent cardiovascular magnetic resonance imaging for assessment of LV mass at baseline and at study completion. The primary objective was to compare change in LV mass index from baseline to follow-up in the combination and losartan arms; the secondary objective was to determine whether aliskiren was noninferior to losartan in reducing LV mass index from baseline to follow-up. Systolic and diastolic blood pressures were reduced similarly in all treatment groups (6.5+/-14.9/3.8+/-10.1 mm Hg in the aliskiren group; 5.5+/-15.6/3.7+/-10.7 mm Hg in the losartan group; 6.6+/-16.6/4.6+/-10.5 mm Hg in the combination arm; P<0.0001 within groups, P=0.81 between groups). LV mass index was reduced significantly from baseline in all treatment groups (4.9-, 4.8-, and 5.8 g/m(2) reductions in the aliskiren, losartan, and combination arms, respectively; P<0.0001 for all treatment groups). The reduction in LV mass index in the combination group was not significantly different from that with losartan alone (P=0.52). Aliskiren was as effective as losartan in reducing LV mass index (P<0.0001 for noninferiority). Safety and tolerability were similar across all treatment groups. Aliskiren was as effective as losartan in promoting LV mass regression. Reduction in LV mass with the combination of aliskiren plus losartan was not significantly different from that with losartan monotherapy, independent of blood pressure lowering. These findings suggest that aliskiren was as effective as an angiotensin receptor blocker in attenuating this measure of myocardial end-organ damage in hypertensive patients with LV hypertrophy.
Mouton, Jomien M; Kinnear, Craig J; Moolman-Smook, Johanna C; Herbst, Philip G; Pellizzon, Adriano S; Goosen, Althea; Brink, Paul A
2015-01-01
Summary Introduction The minimum criterion for the diagnosis of hypertrophic cardiomyopathy (HCM) is thickening of the left ventricular wall, typically in an asymmetrical or focal fashion, and it requires no functional deficit. Using this criterion, we identified a family with four affected individuals and a single unrelated individual essentially with restrictive cardiomyopathy (RCM). Mutations in genes coding for the thin filaments of cardiac muscle have been described in RCM and HCM with ‘restrictive features’. One such gene encodes for cardiac troponin I (TNNI3), a sub-unit of the troponin complex involved in the regulation of striated muscle contraction. We hypothesised that mutations in TNNI3 could underlie this particular phenotype, and we therefore screened TNNI3 for mutations in 115 HCM probands. Methods Clinical investigation involved examination, echocardiography, chest X-ray and an electrocardiogram of both the index cases and close relatives. The study cohort consisted of 113 South African HCM probands, with and without known founder HCM mutations, and 100 ethnically matched control individuals. Mutation screening of TNNI3 for disease-causing mutations were performed using high-resolution melt (HRM) analysis. Results HRM analyses identified three previously described HCM-causing mutations (p.Pro82Ser, p.Arg162Gln, p.Arg170Gln) and a novel exonic variant (p.Leu144His). A previous study involving the same amino acid identified a p.Leu144Gln mutation in a patient presenting with RCM, with clinical features of HCM. We observed the novel p.Leu144His mutation in three siblings with clinical RCM and varying degrees of ventricular hypertrophy. The isolated index case with the de novo p.Arg170Gln mutation presented with a similar phenotype. Both mutations were absent in a healthy control group. Conclusion We have identified a novel disease-causing p.Leu144His mutation and a de novo p.Arg170Gln mutation associated with RCM and focal ventricular hypertrophy, often below the typical diagnostic threshold for HCM. Our study provides information regarding TNNI3 mutations underlying RCM in contrast to other causes of a similar presentation, such as constrictive pericarditis or infiltration of cardiac muscle, all with marked right-sided cardiac manifestations. This study therefore highlights the need for extensive mutation screening of genes encoding for sarcomeric proteins, such as TNNI3 to identify the underlying cause of this particular phenotype. PMID:25940119
Le Quang, Khai; Bouchareb, Rihab; Lachance, Dominic; Laplante, Marc-André; El Husseini, Diala; Boulanger, Marie-Chloé; Fournier, Dominique; Fang, Xiang Ping; Avramoglu, Rita Kohen; Pibarot, Philippe; Deshaies, Yves; Sweeney, Gary; Mathieu, Patrick; Marette, André
2014-10-01
This study aimed to determine the potential impact of type 2 diabetes mellitus on left ventricular dysfunction and the development of calcified aortic valve disease using a dyslipidemic mouse model prone to developing type 2 diabetes mellitus. When compared with nondiabetic LDLr(-/-)/ApoB(100/100), diabetic LDLr(-/-)/ApoB(100/100)/IGF-II mice exhibited similar dyslipidemia and obesity but developed type 2 diabetes mellitus when fed a high-fat/sucrose/cholesterol diet for 6 months. LDLr(-/-)/ApoB(100/100)/IGF-II mice showed left ventricular hypertrophy versus C57BL6 but not LDLr(-/-)/ApoB(100/100) mice. Transthoracic echocardiography revealed significant reductions in both left ventricular systolic fractional shortening and diastolic function in high-fat/sucrose/cholesterol fed LDLr(-/-)/ApoB(100/100)/IGF-II mice when compared with LDLr(-/-)/ApoB(100/100). Importantly, we found that peak aortic jet velocity was significantly increased in LDLr(-/-)/ApoB(100/100)/IGF-II mice versus LDLr(-/-)/ApoB(100/100) animals on the high-fat/sucrose/cholesterol diet. Microtomography scans and Alizarin red staining indicated calcification in the aortic valves, whereas electron microscopy and energy dispersive x-ray spectroscopy further revealed mineralization of the aortic leaflets and the presence of inflammatory infiltrates in diabetic mice. Studies showed upregulation of hypertrophic genes (anp, bnp, b-mhc) in myocardial tissues and of osteogenic genes (spp1, bglap, runx2) in aortic tissues of diabetic mice. We have established the diabetes mellitus -prone LDLr(-/-)/ApoB(100/100)/IGF-II mouse as a new model of calcified aortic valve disease. Our results are consistent with the growing body of clinical evidence that the dysmetabolic state of type 2 diabetes mellitus contributes to early mineralization of the aortic valve and calcified aortic valve disease pathogenesis. © 2014 American Heart Association, Inc.
Maanja, Maren; Wieslander, Björn; Schlegel, Todd T; Bacharova, Ljuba; Abu Daya, Hussein; Fridman, Yaron; Wong, Timothy C; Schelbert, Erik B; Ugander, Martin
2017-01-22
Myocardial fibrosis quantified by myocardial extracellular volume fraction (ECV) and left ventricular mass (LVM) index (LVMI) measured by cardiovascular magnetic resonance might represent independent and opposing contributors to ECG voltage measures of left ventricular hypertrophy (LVH). Diffuse myocardial fibrosis can occur in LVH and interfere with ECG voltage measures. This phenomenon could explain the decreased sensitivity of LVH detectable by ECG, a fundamental diagnostic tool in cardiology. We identified 77 patients (median age, 53 [interquartile range, 26-60] years; 49% female) referred for contrast-enhanced cardiovascular magnetic resonance with ECV measures and 12-lead ECG. Exclusion criteria included clinical confounders that might influence ECG measures of LVH. We evaluated ECG voltage-based LVH measures, including Sokolow-Lyon index, Cornell voltage, 12-lead voltage, and the vectorcardiogram spatial QRS voltage, with respect to LVMI and ECV. ECV and LVMI were not correlated (R 2 =0.02; P=0.25). For all voltage-related parameters, higher LVMI resulted in greater voltage (r=0.33-0.49; P<0.05 for all), whereas increased ECV resulted in lower voltage (r=-0.32 to -0.57; P<0.05 for all). When accounting for body fat, LV end-diastolic volume, and mass-to-volume ratio, both LVMI (β=0.58, P=0.03) and ECV (β=-0.46, P<0.001) were independent predictors of QRS voltage (multivariate adjusted R 2 =0.39; P<0.001). Myocardial mass and diffuse myocardial fibrosis have independent and opposing effects upon ECG voltage measures of LVH. Diffuse myocardial fibrosis quantified by ECV can obscure the ECG manifestations of increased LVM. This provides mechanistic insight, which can explain the limited sensitivity of the ECG for detecting increased LVM. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
Koto, Dan; Izumo, Masaki; Machida, Takafumi; Suzuki, Kengo; Yoneyama, Kihei; Suzuki, Tomomi; Kamijima, Ryo; Kobayashi, Yasuyuki; Harada, Tomoo; Akashi, Yoshihiro J
2018-05-24
It is unclear how upper septal hypertrophy (USH) affects Doppler-derived left ventricular stroke volume (SV) in patients with AS. The aims of this study were to: (1) validate the accuracy of 3D transesophageal echocardiography (TEE) measurements of the left ventricular outflow tract (LVOT), (2) evaluate the differences in LVOT geometry between AS patients with and without USH, and (3) assess the impact of USH on measurement of SV. In protocol 1, both 3D TEE and multi-detector computed tomography were performed in 20 patients with AS [aortic valve area (AVA) ≤ 1.5 cm 2 ]. Multiplanar reconstruction was used to measure the LVOT short and long diameters in four parts from the tip of the septum to the annulus. In protocol 2, the same 3D TEE measurements were performed in AS patients (AVA ≤ 1.5 cm 2 , n = 129) and controls (n = 30). We also performed 2D and 3D transthoracic echocardiography in all patients. In protocol 1, excellent correlations of LVOT parameters were found between the two modalities. In protocol 2, the USH group had smaller LVOT short and long diameters than the non-USH group. Although no differences in mean pressure gradient, or SV calculated with the 3D method existed between the two groups, the USH group had greater SV calculated with the Doppler method (73 ± 15 vs. 66 ± 15 ml) and aortic valve area (0.89 ± 0.26 vs. 0.73 ± 0.24 cm 2 ) than the non-USH group. 3D TEE can provide a precise assessment of the LVOT in AS. USH affects the LVOT geometry in patients with AS, which might lead to inaccurate assessments of disease severity.
Galanti, Giorgio; Toncelli, Loira; Del Furia, Francesca; Stefani, Laura; Cappelli, Brunello; De Luca, Alessio; Vono, Maria Concetta Roberta
2009-01-01
Background Transthoracic echocardiography left ventricular wall thickness is often increased in master athletes and it results by intense physical training. Left Ventricular Hypertrophy can also be due to a constant pressure overload. Conventional Pulsed Wave (PW) Doppler analysis of diastolic function sometimes fails to distinguish physiological from pathological LVH. The aim of this study is to evaluate the role of Pulsed Wave Tissue Doppler Imaging in differentiating pathological from physiological LVH in the middle-aged population. Methods we selected a group of 80 master athletes, a group of 80 sedentary subjects with essential hypertension and an apparent normal diastolic function at standard PW Doppler analysis. The two groups were comparable for increased left ventricular wall thickness and mass index (134.4 ± 19.7 vs 134.5 ± 22.1 gr/m2; p > .05). Diastolic function indexes using the PW technique were in the normal range for both. Results Pulsed Wave TDI study of diastolic function immediately distinguished the two groups. While in master athletes the diastolic TDI-derived parameters remained within normal range (E' 9.4 ± 3.1 cm/sec; E/E' 7.8 ± 2.1), in the hypertensive group these parameters were found to be constantly altered, with mean values and variation ranges always outside normal validated limits (E' 7.2 ± 2.4 cm/sec; E/E' 10.6 ± 3.2), and with E' and E/E' statistically different in the two groups (p < .001). Conclusion Our study showed that the TDI technique can be an easy and validated method to assess diastolic function in differentiating normal from pseudonormal diastolic patterns and it can distinguish physiological from pathological LVH emphasizing the eligibility certification required by legal medical legislation as in Italy. PMID:19845938
Zinc Levels in Left Ventricular Hypertrophy.
Huang, Lei; Teng, Tianming; Bian, Bo; Yao, Wei; Yu, Xuefang; Wang, Zhuoqun; Xu, Zhelong; Sun, Yuemin
2017-03-01
Zinc is one of the most important trace elements in the body and zinc homeostasis plays a critical role in maintaining cellular structure and function. Zinc dyshomeostasis can lead to many diseases, such as cardiovascular disease. Our aim was to investigate whether there is a relationship between zinc and left ventricular hypertrophy (LVH). A total of 519 patients was enrolled and their serum zinc levels were measured in this study. We performed analyses on the relationship between zinc levels and LVH and the four LV geometry pattern patients: normal LV geometry, concentric remodeling, eccentric LVH, and concentric LVH. We performed further linear and multiple regression analyses to confirm the relationship between zinc and left ventricular mass (LVM), left ventricular mass index (LVMI), and relative wall thickness (RWT). Our data showed that zinc levels were 710.2 ± 243.0 μg/L in the control group and were 641.9 ± 215.2 μg/L in LVH patients. We observed that zinc levels were 715 ± 243.5 μg/L, 694.2 ± 242.7 μg/L, 643.7 ± 225.0 μg/L, and 638.7 ± 197.0 μg/L in normal LV geometry, concentric remodeling, eccentric LVH, and concentric LVH patients, respectively. We further found that there was a significant inverse linear relationship between zinc and LVM (p = 0.001) and LVMI (p = 0.000) but did not show a significant relationship with RWT (p = 0.561). Multiple regression analyses confirmed that the linear relationship between zinc and LVM and LVMI remained inversely significant. The present study revealed that serum zinc levels were significantly decreased in the LVH patients, especially in the eccentric LVH and concentric LVH patients. Furthermore, zinc levels were significantly inversely correlated with LVM and LVMI.
Duchna, Hans-Werner; Myslinski, Wojciech; Dichmann, Manuel; Rasche, Kurt; Schultze-Werninghaus, Gerhard; Orth, Maritta
2006-01-15
30% of patients with arterial hypertension (AH) are supposed to have a co-prevalent obstructive sleep apnea syndrome (OSAS). Hence, the influence of CPAP (continuous positive airway pressure) therapy on cardiac structure and function was investigated in medically treated patients with AH and co-prevalent OSAS. In all patients AH was treated for at least 5 years. Matched pairs concerning anthropometric data, medical therapy and duration of AH, and severity of OSAS were investigated: 20 patients with untreated OSAS were compared to 20 patients with CPAP therapy for at least 6 months. Further cardiopulmonary diseases were excluded. Cardiac structure and function were assessed echocardiographically. Patients under CPAP therapy had significantly better diastolic left ventricular function, a lower left ventricular mass index, and significantly less frequent signs of left ventricular (eccentric) hypertrophy than patients with untreated OSAS. Furthermore, differences were significant concerning right ventricular wall thickness and mean pulmonary artery pressure. CPAP therapy positively influences left and right cardial structure and function in addition to antihypertensive medication in patients with AH and co-prevalent OSAS.
Kwak, Dongmin; Wang, Huan; Liu, Xiaoyu; Hu, Xinli; Bache, Robert J.; Chen, Yingjie
2013-01-01
Aberrant cardiomyocyte microtubule growth is a feature of pressure overload induced cardiac hypertrophy believed to contribute to left ventricular (LV) dysfunction. Microtubule Actin Cross-linking Factor 1 (MACF1/Acf7) is a 600 kd spectraplakin that stabilizes and guides microtubule growth along actin filaments. MACF1 is expressed in the heart, but its impact on cardiac microtubules, and how this influences cardiac structure, function, and adaptation to hemodynamic overload is unknown. Here we used inducible cardiac-specific MACF1 knockout mice (MACF1 KO) to determine the impact of MACF1 on cardiac microtubules and adaptation to pressure overload (transverse aortic constriction (TAC).In adult mouse hearts, MACF1 expression was low under basal conditions, but increased significantly in response to TAC. While MACF1 KO had no observable effect on heart size or function under basal conditions, MACF1 KO exacerbated TAC induced LV hypertrophy, LV dilation and contractile dysfunction. Interestingly, subcellular fractionation of ventricular lysates revealed that MACF1 KO altered microtubule distribution in response to TAC, so that more tubulin was associated with the cell membrane fraction. Moreover, TAC induced microtubule redistribution into this cell membrane fraction in both WT and MACF1 KO mice correlated strikingly with the level of contractile dysfunction (r2 = 0.786, p<.001). MACF1 disruption also resulted in reduction of membrane caveolin 3 levels, and increased levels of membrane PKCα and β1 integrin after TAC, suggesting MACF1 function is important for spatial regulation of several physiologically relevant signaling proteins during hypertrophy. Together, these data identify for the first time, a role for MACF1 in cardiomyocyte microtubule distribution and in adaptation to hemodynamic overload. PMID:24086300
Fassett, John T; Xu, Xin; Kwak, Dongmin; Wang, Huan; Liu, Xiaoyu; Hu, Xinli; Bache, Robert J; Chen, Yingjie
2013-01-01
Aberrant cardiomyocyte microtubule growth is a feature of pressure overload induced cardiac hypertrophy believed to contribute to left ventricular (LV) dysfunction. Microtubule Actin Cross-linking Factor 1 (MACF1/Acf7) is a 600 kd spectraplakin that stabilizes and guides microtubule growth along actin filaments. MACF1 is expressed in the heart, but its impact on cardiac microtubules, and how this influences cardiac structure, function, and adaptation to hemodynamic overload is unknown. Here we used inducible cardiac-specific MACF1 knockout mice (MACF1 KO) to determine the impact of MACF1 on cardiac microtubules and adaptation to pressure overload (transverse aortic constriction (TAC).In adult mouse hearts, MACF1 expression was low under basal conditions, but increased significantly in response to TAC. While MACF1 KO had no observable effect on heart size or function under basal conditions, MACF1 KO exacerbated TAC induced LV hypertrophy, LV dilation and contractile dysfunction. Interestingly, subcellular fractionation of ventricular lysates revealed that MACF1 KO altered microtubule distribution in response to TAC, so that more tubulin was associated with the cell membrane fraction. Moreover, TAC induced microtubule redistribution into this cell membrane fraction in both WT and MACF1 KO mice correlated strikingly with the level of contractile dysfunction (r(2) = 0.786, p<.001). MACF1 disruption also resulted in reduction of membrane caveolin 3 levels, and increased levels of membrane PKCα and β1 integrin after TAC, suggesting MACF1 function is important for spatial regulation of several physiologically relevant signaling proteins during hypertrophy. Together, these data identify for the first time, a role for MACF1 in cardiomyocyte microtubule distribution and in adaptation to hemodynamic overload.
Lai, Chin-Chih; Sun, Dianjianyi; Cen, Ruiqi; Wang, Jian; Li, Shengxu; Fernandez-Alonso, Camilo; Chen, Wei; Srinivasan, Sathanur R; Berenson, Gerald S
2014-10-14
Cardiovascular risk factors are associated with left ventricular hypertrophy (LVH), but little is known regarding related impact of longitudinal measures of childhood adiposity and LV hemodynamic variables. The aim of this study was to examine the impact of cumulative long-term burden and trends of excessive adiposity and elevated blood pressure (BP) during childhood on adulthood LVH and LV geometric remodeling patterns. This longitudinal study consisted of 1,061 adults, age 24 to 46 years, who had been examined 4 or more times for body mass index (BMI) and BP starting in childhood, with a mean follow-up of 28.0 years. The area under the curve (AUC) was calculated as a measure of long-term burden (total AUC) and trends (incremental AUC) of BMI and BP from childhood to adulthood. Four LV geometric types were defined-normal, concentric remodeling (CR), eccentric hypertrophy (EH), and concentric hypertrophy (CH)-all on the basis of LV mass indexed for body height (m(2.7)) and relative wall thickness. Higher values of BMI and systolic and diastolic BP in childhood and adulthood, as well as total AUC and incremental AUC, were all significantly associated with higher LV mass index and LVH, adjusted for race, sex, and age. In addition, higher values of BMI and BP in childhood and adulthood, total AUC, and incremental AUC were significantly associated with EH and CH but not with CR. Importantly, all of these measures of BMI had a consistently and significantly greater influence on EH than did measures of BP. These findings indicate that the adverse influence of excessive adiposity and elevated BP levels on LVH begins in childhood. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Byrne, Nikole J; Levasseur, Jody; Sung, Miranda M; Masson, Grant; Boisvenue, Jamie; Young, Martin E; Dyck, Jason R B
2016-05-15
Impaired cardiac substrate metabolism plays an important role in heart failure (HF) pathogenesis. Since many of these metabolic changes occur at the transcriptional level of metabolic enzymes, it is possible that this loss of metabolic flexibility is permanent and thus contributes to worsening cardiac function and/or prevents the full regression of HF upon treatment. However, despite the importance of cardiac energetics in HF, it remains unclear whether these metabolic changes can be normalized. In the current study, we investigated whether a reversal of an elevated aortic afterload in mice with severe HF would result in the recovery of cardiac function, substrate metabolism, and transcriptional reprogramming as well as determined the temporal relationship of these changes. Male C57Bl/6 mice were subjected to either Sham or transverse aortic constriction (TAC) surgery to induce HF. After HF development, mice with severe HF (% ejection fraction < 30) underwent a second surgery to remove the aortic constriction (debanding, DB). Three weeks following DB, there was a near complete recovery of systolic and diastolic function, and gene expression of several markers for hypertrophy/HF were returned to values observed in healthy controls. Interestingly, pressure-overload-induced left ventricular hypertrophy (LVH) and cardiac substrate metabolism were restored at 1-week post-DB, which preceded functional recovery. The regression of severe HF is associated with early and dramatic improvements in cardiac energy metabolism and LVH normalization that precede restored cardiac function, suggesting that metabolic and structural improvements may be critical determinants for functional recovery. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.
Calò, Lorenzo A; Vertolli, Ugo; Pagnin, Elisa; Ravarotto, Verdiana; Davis, Paul A; Lupia, Mario; Naso, Elena; Maiolino, Giuseppe; Naso, Agostino
2016-03-01
Cardiovascular disease (CVD) is the leading cause of excess mortality in chronic kidney disease (CKD) and dialysis patients (DP) who have higher prevalence of left ventricular hypertrophy (LVH), the strongest predictor of CV events. Rho kinase (ROCK) activation is linked in hypertensive patients to cardiac remodeling while ROCK inhibition suppresses cardiomyocyte hypertrophy and, in a human clinical condition opposite to hypertension, its downregulation associates with lack of CV remodeling. Information on ROCK activation-LVH link in CKD and DP is lacking. Mononuclear cells (PBMCs) MYPT-1 phosphorylation, a marker of ROCK activity, and the effect of fasudil, a ROCK inhibitor, on MYPT-1 phosphorylation were assessed in 23 DPs, 13 stage 3-4 CKD and 36 healthy subjects (HS) by Western blot. LV mass was assessed by M-mode echocardiography. DP and CKD had higher MYPT-1 phosphorylation compared to HS (p<0.001 and p=0.003). Fasudil (500 and 1000μM) dose dependently reduced MYPT-1 phosphorylation in DP (p<0.01). DP had higher LV mass than CKD (p<0.001). MYPT-1 phosphorylation was higher in patients with LVH (p=0.009) and correlated with LV mass both in DP and CKD with LVH (p<0.001 and p=0.006). In DP and CKD, ROCK activity tracks with LVH. This ROCK activation-LVH link provided in these CVD high-risk patients along with similar findings in hypertensive patients and added to opposite findings in a human model opposite to hypertension and in type 2 diabetic patients, identify ROCK activation as a potential LVH marker and provide further rationale for ROCK activation inhibition as target of therapy in CVD high-risk patients. Copyright © 2016 Elsevier Inc. All rights reserved.
Zhao, Li-li; Chen, Hong-juan; Chen, Jun-zhu; Yu, Min; Ni, Yun-lan; Zhang, Wei-fang
2008-01-01
Objective: To assess the effect of angiotensin II type 1 (AT1) receptor antagonist losartan on myocardium connexin43 (Cx43) gap junction (GJ) expression in spontaneously hypertensive rats (SHRs) and investigate possible mechanisms. Methods: Sixteen 9-week-old male SHRs and 8 age-matched male Wistar-Kyoto (WKY) rats were included in this study. SHRs were randomly divided into two groups to receive losartan at 30 mg/(kg·d) by oral gavage once daily for 8 weeks (SHR-L) or vehicle (0.9% saline) to act as controls (SHR-V); WKY rats receiving vehicle for 8 weeks served as normotensive controls. At the end of the experiment, rats were sacrificed and the hearts were removed. Expressions of Cx43 and nuclear factor-kappaB p65 (NF-κB p65) proteins in all three groups were observed and further investigations on the effect of angiotensin II type 1 receptor antagonist losartan (30 mg/(kg·d), 8 weeks) on Cx43 expression were conducted with Western blot and immunohistochemistry. NF-κB p65 protein in nuclear extracts was determined by Western blot. Results: Left ventricular (LV) hypertrophy was prominent in SHRs, Cx43 and NF-κB p65 protein expressions were obviously upregulated and Cx43 distribution was dispersed over the cell surface. Treatment with losarton reduced the over-expressions of Cx43 and NF-κB p65 in LV myocardium. The distribution of Cx43 gap junction also became much regular and confined to intercalated disk after losartan treatment. Conclusion: Cx43 level was upregulated in LV myocardium of SHR during early stage of hypertrophy. Angiotensin II type 1 receptor antagonist losartan prevented Cx43 gap junction remodeling in hypertrophied left ventricles, possibly through the NF-κB pathway. PMID:18543397
Hwang, Hyun Seok; Bleske, Barry E; Ghannam, Michael M J; Converso, Kimber; Russell, Mark W; Hunter, James C; Boluyt, Marvin O
2008-02-01
Hawthorn (Crataegus) is a natural product used to treat patients with heart failure. The effects of hawthorn on cardiac remodeling, however, are not known. The purpose was to determine the effects of hawthorn treatment on remodeling and function of the left ventricle (LV) after 1 month of pressure overload-induced cardiac hypertrophy. Sprague-Dawley rats (male, 300 g) were subjected to sham operation (SH) or aortic constriction (AC) for 4 weeks and treated with Hawthorn (Crataegus-Extract- WS1442;1.3, 13, 130 mg kg(-1) day(-1); AC-L, AC-M, AC-H) or vehicle (SH-V, AC-V) for 3 weeks after surgery. Systolic and diastolic function were measured using echocardiographic assessment at baseline and 4 weeks after AC. AC increased the LV/body weight ratio by 34% in vehicle and hawthorn treated rats. Hawthorn markedly reduced LV chamber volumes (VOL) after AC [systolic VOL, mean +/- SEM, mm(3): SH-V, 87 +/- 13; AC-V, 93 +/- 12; AC-L, 62 +/- 9; AC-M, 68 +/- 12; AC-H; 50 +/- 11 and diastolic VOL: SH-V, 433 +/- 45; AC-V, 412 +/- 57; AC-L, 313 +/- 25; AC-M, 319 +/- 37; AC-H, 264 +/- 25 (p < 0.05)] and augmented relative wall thickness, mm: SH-V, 0.45 +/- 0.02; AC-V, 0.65 +/- 0.05; AC-L, 0.71 +/- 0.03; AC-M, 0.74 +/- 0.06; AC-H, 0.80 +/- 0.09 (p < 0.05). AC reduced velocity of circumferential shortening (Vcf(c)) by 28% compared with SH-V. Hawthorn attenuated the AC-induced decrease in Vcf(c) (p < 0.05). Hawthorn treatment modifies left ventricular remodeling and counteracts myocardial dysfunction in early pressure overload-induced cardiac hypertrophy.
Ikeda, Shohei; Satoh, Kimio; Kikuchi, Nobuhiro; Miyata, Satoshi; Suzuki, Kota; Omura, Junichi; Shimizu, Toru; Kobayashi, Kenta; Kobayashi, Kazuto; Fukumoto, Yoshihiro; Sakata, Yasuhiko; Shimokawa, Hiroaki
2014-06-01
Right ventricular (RV) failure is the leading cause of death in various cardiopulmonary diseases, including pulmonary hypertension. It is generally considered that the RV is vulnerable to pressure overload as compared with the left ventricle (LV). However, as compared with LV failure, the molecular mechanisms of RV failure are poorly understood, and hence therapeutic targets of the disorder remain to be elucidated. Thus, we aimed to identify molecular therapeutic targets for RV failure in a mouse model of pressure overload. To induce pressure overload to respective ventricles, we performed pulmonary artery constriction or transverse aortic constriction in mice. We first performed microarray analysis and found that the molecules related to RhoA/Rho-kinase and integrin pathways were significantly upregulated in the RV with pulmonary artery constriction compared with the LV with transverse aortic constriction. Then, we examined the responses of both ventricles to chronic pressure overload in vivo. We demonstrated that compared with transverse aortic constriction, pulmonary artery constriction caused greater extents of mortality, Rho-kinase expression (especially ROCK2 isoform), and oxidative stress in pressure-overloaded RV, reflecting the weakness of the RV in response to pressure overload. Furthermore, mice with myocardial-specific overexpression of dominant-negative Rho-kinase showed resistance to pressure overload-induced hypertrophy and dysfunction associated with reduced oxidative stress. Finally, dominant-negative Rho-kinase mice showed a significantly improved long-term survival in both pulmonary artery constriction and transverse aortic constriction as compared with littermate controls. These results indicate that the Rho-kinase pathway plays a crucial role in RV hypertrophy and dysfunction, suggesting that the pathway is a novel therapeutic target of RV failure in humans. © 2014 American Heart Association, Inc.
Ahmad, A; Sattar, M A; Rathore, H A; Abdulla, M H; Khan, S A; Abdullah, N A; Johns, E J
2016-02-01
The present study investigated the role of endothelial nitric oxide synthase (eNOS) enzyme in the development of left ventricular hypertrophy (LVH) in Wistar-Kyoto rats. The effect of L-arginine administration on cardiac structure, arterial stiffness, renal and systemic hemodynamic parameters was studied and the change in expression of eNOS and cystathione γ lyase (CSE) in the myocardium of LVH rats was evaluated. LVH was induced using isoprenaline (5 mg/kg, S.C.) and caffeine (62 mg/L in drinking water) for 14 days. Following to that, L-arginine (1.25 g/L in drinking water) was given for 5 weeks as a donor of NO. eNOS and CSE gene expressions were down regulated in the LVH group by about 35% and 67% respectively when compared to control. However, in the LVH group treated with L-arginine there was up regulation of eNOS by almost 27% and down regulation in CSE by 24% when compared to control (all P < 0.05). Heart index and H2S plasma levels were reduced by almost 53% in the L-arginine treated LVH group compared to the control (all P < 0.05). Mean arterial pressure, heart rate and pulse wave velocity were reduced while renal blood perfusion increased in L-arginine treated LVH rats compared to their untreated counterparts (all P < 0.05). The enhanced expression of eNOS in L-arginine treated LVH rats resulted in the amelioration of oxidative and haemodynamic parameters suggesting that NO system is an important therapeutic target in cardiac and LV hypertrophies.
Cardiac hypertrophy limits infarct expansion after myocardial infarction in mice.
Iismaa, Siiri E; Li, Ming; Kesteven, Scott; Wu, Jianxin; Chan, Andrea Y; Holman, Sara R; Calvert, John W; Haq, Ahtesham Ul; Nicks, Amy M; Naqvi, Nawazish; Husain, Ahsan; Feneley, Michael P; Graham, Robert M
2018-04-17
We have previously demonstrated that adult transgenic C57BL/6J mice with CM-restricted overexpression of the dominant negative W v mutant protein (dn-c-kit-Tg) respond to pressure overload with robust cardiomyocyte (CM) cell cycle entry. Here, we tested if outcomes after myocardial infarction (MI) due to coronary artery ligation are improved in this transgenic model. Compared to non-transgenic littermates (NTLs), adult male dn-c-kit-Tg mice displayed CM hypertrophy and concentric left ventricular (LV) hypertrophy in the absence of an increase in workload. Stroke volume and cardiac output were preserved and LV wall stress was markedly lower than that in NTLs, leading to a more energy-efficient heart. In response to MI, infarct size in adult (16-week old) dn-c-kit-Tg hearts was similar to that of NTL after 24 h but was half that in NTL hearts 12 weeks post-MI. Cumulative CM cell cycle entry was only modestly increased in dn-c-kit-Tg hearts. However, dn-c-kit-Tg mice were more resistant to infarct expansion, adverse LV remodelling and contractile dysfunction, and suffered no early death from LV rupture, relative to NTL mice. Thus, pre-existing cardiac hypertrophy lowers wall stress in dn-c-kit-Tg hearts, limits infarct expansion and prevents death from myocardial rupture.
Klein, Franziska J; Bell, Stephen; Runte, K Elisabeth; Lobel, Robert; Ashikaga, Takamuru; Lerman, Lilach O; LeWinter, Martin M; Meyer, Markus
2016-10-01
Lowering the heart rate is considered to be beneficial in heart failure (HF) with reduced ejection fraction (HFrEF). In a dilated left ventricle (LV), pharmacological heart rate lowering is associated with a reduction in LV chamber size. In patients with HFrEF, this structural change is associated with better survival. HF with preserved ejection fraction (HFpEF) is increasingly prevalent but, so far, without any evidence-based treatment. HFpEF is typically associated with LV concentric remodeling and hypertrophy. The effects of heart rate on this structural phenotype are not known. Analogous with the benefits of a low heart rate on a dilated heart, we hypothesized that increased heart rates could lead to potentially beneficial remodeling of a concentrically hypertrophied LV. This was explored in an established porcine model of concentric LV hypertrophy and fibrosis. Our results suggest that a moderate increase in heart rate can be used to reduce wall thickness, normalize LV chamber volumes, decrease myocardial fibrosis, and improve LV compliance. Our results also indicate that the effects of heart rate can be titrated, are reversible, and do not induce HF. These findings may provide the rationale for a novel therapeutic approach for HFpEF and its antecedent disease substrate. Copyright © 2016 the American Physiological Society.
Suppression of class I and II histone deacetylases blunts pressure-overload cardiac hypertrophy.
Kong, Yongli; Tannous, Paul; Lu, Guangrong; Berenji, Kambeez; Rothermel, Beverly A; Olson, Eric N; Hill, Joseph A
2006-06-06
Recent work has demonstrated the importance of chromatin remodeling, especially histone acetylation, in the control of gene expression in the heart. In cell culture models of cardiac hypertrophy, pharmacological suppression of histone deacetylases (HDACs) can either blunt or amplify cell growth. Thus, HDAC inhibitors hold promise as potential therapeutic agents in hypertrophic heart disease. In the present investigation, we studied 2 broad-spectrum HDAC inhibitors in a physiologically relevant banding model of hypertrophy, observing dose-responsive suppression of ventricular growth that was well tolerated in terms of both clinical outcome and cardiac performance measures. In both short-term (3-week) and long-term (9-week) trials, cardiomyocyte growth was blocked by HDAC inhibition, with no evidence of cell death or apoptosis. Fibrotic change was diminished in hearts treated with HDAC inhibitors, and collagen synthesis in isolated cardiac fibroblasts was blocked. Preservation of systolic function in the setting of blunted hypertrophic growth was documented by echocardiography and by invasive pressure measurements. The hypertrophy-associated switch of adult and fetal isoforms of myosin heavy chain expression was attenuated, which likely contributed to the observed preservation of systolic function in HDAC inhibitor-treated hearts. Together, these data suggest that HDAC inhibition is a viable therapeutic strategy that holds promise in the treatment of load-induced heart disease.
Tigchelaar, Wardit; Yu, Hongjuan; de Jong, Anne Margreet; van Gilst, Wiek H; van der Harst, Pim; Westenbrink, B Daan; de Boer, Rudolf A; Silljé, Herman H W
2015-01-15
Recently, a locus at the mitochondrial exo/endonuclease EXOG gene, which has been implicated in mitochondrial DNA repair, was associated with cardiac function. The function of EXOG in cardiomyocytes is still elusive. Here we investigated the role of EXOG in mitochondrial function and hypertrophy in cardiomyocytes. Depletion of EXOG in primary neonatal rat ventricular cardiomyocytes (NRVCs) induced a marked increase in cardiomyocyte hypertrophy. Depletion of EXOG, however, did not result in loss of mitochondrial DNA integrity. Although EXOG depletion did not induce fetal gene expression and common hypertrophy pathways were not activated, a clear increase in ribosomal S6 phosphorylation was observed, which readily explains increased protein synthesis. With the use of a Seahorse flux analyzer, it was shown that the mitochondrial oxidative consumption rate (OCR) was increased 2.4-fold in EXOG-depleted NRVCs. Moreover, ATP-linked OCR was 5.2-fold higher. This increase was not explained by mitochondrial biogenesis or alterations in mitochondrial membrane potential. Western blotting confirmed normal levels of the oxidative phosphorylation (OXPHOS) complexes. The increased OCR was accompanied by a 5.4-fold increase in mitochondrial ROS levels. These increased ROS levels could be normalized with specific mitochondrial ROS scavengers (MitoTEMPO, mnSOD). Remarkably, scavenging of excess ROS strongly attenuated the hypertrophic response. In conclusion, loss of EXOG affects normal mitochondrial function resulting in increased mitochondrial respiration, excess ROS production, and cardiomyocyte hypertrophy. Copyright © 2015 the American Physiological Society.
CaM kinase signaling induces cardiac hypertrophy and activates the MEF2 transcription factor in vivo
Passier, Robert; Zeng, Hong; Frey, Norbert; Naya, Francisco J.; Nicol, Rebekka L.; McKinsey, Timothy A.; Overbeek, Paul; Richardson, James A.; Grant, Stephen R.; Olson, Eric N.
2000-01-01
Hypertrophic growth is an adaptive response of the heart to diverse pathological stimuli and is characterized by cardiomyocyte enlargement, sarcomere assembly, and activation of a fetal program of cardiac gene expression. A variety of Ca2+-dependent signal transduction pathways have been implicated in cardiac hypertrophy, but whether these pathways are independent or interdependent and whether there is specificity among them are unclear. Previously, we showed that activation of the Ca2+/calmodulin-dependent protein phosphatase calcineurin or its target transcription factor NFAT3 was sufficient to evoke myocardial hypertrophy in vivo. Here, we show that activated Ca2+/calmodulin-dependent protein kinases-I and -IV (CaMKI and CaMKIV) also induce hypertrophic responses in cardiomyocytes in vitro and that CaMKIV overexpressing mice develop cardiac hypertrophy with increased left ventricular end-diastolic diameter and decreased fractional shortening. Crossing this transgenic line with mice expressing a constitutively activated form of NFAT3 revealed synergy between these signaling pathways. We further show that CaMKIV activates the transcription factor MEF2 through a posttranslational mechanism in the hypertrophic heart in vivo. Activated calcineurin is a less efficient activator of MEF2-dependent transcription, suggesting that the calcineurin/NFAT and CaMK/MEF2 pathways act in parallel. These findings identify MEF2 as a downstream target for CaMK signaling in the hypertrophic heart and suggest that the CaMK and calcineurin pathways preferentially target different transcription factors to induce cardiac hypertrophy. PMID:10811847
Ernst, Michael E.; Davis, Barry R.; Soliman, Elsayed Z.; Prineas, Ronald J.; Okin, Peter M.; Ghosh, Alokananda; Cushman, William C.; Einhorn, Paula T.; Oparil, Suzanne; Grimm, Richard H.
2016-01-01
Left ventricular hypertrophy (LVH) predicts cardiovascular risk in hypertensive patients. We analyzed baseline/follow-up ECGs in 26,376 ALLHAT participants randomized to amlodipine (A), lisinopril (L), or chlorthalidone (C). Prevalent/incident LVH were examined using continuous and categorical classifications of Cornell voltage. At 2- and 4-years, prevalence of LVH in the C-group (5.57%; 6.14%) was not statistically different from A-group (2-years: 5.47%; p=0.806, 4-years: 6.54%; p=0.857), or L-group (2-years: 5.64%; p=0.857, 4-years: 6.50%; p=0.430). Incident LVH followed similarly, with no difference at 2-years for C (2.99%) compared to A (2.57%; p=0.173) or L (3.16%; p=0.605), and at 4-years (C=3.52%, A=3.29%, L=3.71%; p=0.521 C vs A, p=0.618 C vs L). Mean Cornell voltage decreased comparably across treatment groups (Δ baseline, 2-years = +3 to -27 μV, ANOVA p=0.8612; 4-years = +10 to -17 μV, ANOVA p=0.9692). We conclude that risk reductions associated with C treatment in secondary endpoints of ALLHAT cannot be attributed to differential improvements in ECG LVH. PMID:27938852
Keating, Gillian M
2009-06-18
Losartan/hydrochlorothiazide (HCTZ) [Hyzaar(R)] is a fixed-dose combination of the angiotensin II receptor antagonist (angiotensin receptor blocker [ARB]) losartan and the thiazide diuretic HCTZ. It is indicated for the treatment of hypertension (including as initial therapy in severe hypertension) and for stroke risk reduction in patients with hypertension and left ventricular hypertrophy (LVH). Losartan/HCTZ is an effective combination therapy, lowering blood pressure (BP) to a greater extent than losartan or HCTZ alone in patients with hypertension. Other ARB/HCTZ fixed-dose combinations generally lowered BP to a greater extent than losartan/HCTZ in patients with hypertension, although whether this translates into improvements in cardiovascular outcomes is not known. In the LIFE study, losartan-based therapy was associated with a lower incidence of cardiovascular morbidity and mortality than atenolol-based therapy, mainly as a result of a reduced risk of stroke; the incidence of new-onset diabetes mellitus was also lower with losartan-based therapy. Losartan/HCTZ is a well tolerated combination therapy. Thus, losartan/HCTZ remains an important option in the treatment of hypertension, as well as being indicated to reduce stroke risk in patients with hypertension and LVH.
Shamim, Shariq; McCrary, Justin; Wayne, Lori; Gratton, Matthew
2014-01-01
Background Prompt reperfusion has been shown to improve outcomes in patients with acute ST-segment elevation myocardial infarction (STEMI) with a goal of culprit vessel patency in <90 minutes. This requires a coordinated approach between the emergency medical services (EMS), emergency department (ED) and interventional cardiology. The urgency of this process can contribute to inappropriate cardiac catheterization laboratory (CCL) activations. Objectives One of the major determinants of inappropriate activations has been misinterpretation of the electrocardiogram (ECG) in the patient with acute chest pain. Methods We report the ECG findings for all CCL activations over an 18-month period after the inception of a STEMI program at our institution. Results There were a total of 139 activations with 77 having a STEMI diagnosis confirmed and 62 activations where there was no STEMI. The inappropriate activations resulted from a combination of atypical symptoms and misinterpretation of the ECG (45% due to anterior ST-segment elevation) on patient presentation. The electrocardiographic abnormalities were particularly problematic in African-Americans with left ventricular hypertrophy. Conclusions In this single-center, prospective observational study, nearly half of the inappropriate STEMI activations were due to the misinterpretation of anterior ST-segment elevation and this finding was commonly seen in African-Americans with left ventricular hypertrophy. PMID:25009790
The role of mitofilin in left ventricular hypertrophy in hemodialysis patients.
Wu, Qi-Shun; He, Qing; He, Jian-Qiang; Chao, Jun; Wang, Wen-Yan; Zhou, Yan; Lou, Ji-Zhuang; Kong, Wei; Chen, Jun-Feng
2018-11-01
Left ventricular hypertrophy (LVH) is a common abnormality in hemodialysis (HD) patients. Mitochondrial dysfunction contributes to the progression of LVH. As an inner mitochondrial membrane structural protein, mitofilin plays a key role in maintaining mitochondrial structure and function. The aim of this study was to investigate the relationship between mitofilin and LVH in HD patients. A total of 98 HD patients and 32 healthy controls were included in the study. Serum N-terminal proBNP (NT-proBNP), endothelin-1 (ET-1), and atrial natriuretic peptide (ANP) were examined. The protein level of mitofilin and the mitochondrial DNA (mtDNA) copy number were estimated in peripheral blood mononuclear cells (PBMCs). The left ventricle mass index (LVMI) was evaluated in all participants, and the interaction between these variables and the LVMI was assessed. The LVMI was positively correlated with the NT-proBNP, ET-1, and ANP levels, and it was negatively correlated with mtDNA copy number and mitofilin levels. Multiple regression analysis showed that the NT-proBNP, ET-1, and ANP levels as well as mitofilin levels and mtDNA copy number were associated with the LVMI. Although further research of these associations is needed, this result suggests that LVH may affect the levels of mitofilin in HD patients.
Nakagawa, Naoki; Maruyama, Hiroki; Ishihara, Takayuki; Seino, Utako; Kawabe, Jun-ichi; Takahashi, Fumihiko; Kobayashi, Motoi; Yamauchi, Atsushi; Sasaki, Yukie; Sakamoto, Naka; Ota, Hisanobu; Tanabe, Yasuko; Takeuchi, Toshiharu; Takenaka, Toshihiro; Kikuchi, Kenjiro; Hasebe, Naoyuki
2011-01-01
Fabry disease is an X-linked lysosomal storage disorder caused by mutations of the α-galactosidase A gene (GLA), and the disease is a relatively prevalent cause of left ventricular hypertrophy mimicking idiopathic hypertrophic cardiomyopathy. We assessed clinically 5 patients of a three-generation family and also searched for GLA mutations in 10 family members. The proband had left ventricular hypertrophy with localized thinning in the basal posterior wall and late gadolinium enhancement (LGE) in the near-circumferential wall in cardiovascular magnetic resonance images and her sister had vasospastic angina pectoris without organic stenosis of the coronary arteries. LGE notably appeared in parallel with decreased α-galactosidase A activity and increased NT-pro BNP in our patients. We detected a new GLA missense mutation (G195V) in exon 4, resulting in a glycine-to-valine substitution. Of the 10 family members, 5 family members each were positive and negative for this mutation. These new data extend our clinical and molecular knowledge of GLA gene mutations and confirm that a novel missense mutation in the GLA gene is important not only for a precise diagnosis of heterozygous status, but also for confirming relatives who are negative for this mutation.
Xie, He-Hui; Miao, Chao-Yu; Liu, Jian-Guo; Su, Ding-Feng
2002-12-01
To study the importance of reduction of blood pressure variability (BPV) in the organ protection of long-term treatment with combination of nitrendipine and atenolol, which was abbreviated as Nile, in spontaneously hypertensive rats (SHR). Combination of nitrendipine (10 mg/kg/d) and atenolol (20 mg/kg/d) was given in SHR chow for 12 weeks. Blood pressure (BP) was then recorded during 24 h in conscious state. After the determination of baroreflex sensitivity (BRS), rats were killed for organ-damage evaluation. Long-term treatment with Nile significantly decreased BP and BPV, ameliorated impaired BRS, and obviously diminished end-organ damage in SHR. The indices of left ventricular and aortic hypertrophy, and glomerulosclerosis score were all positively related to BP and BPV, and negatively related to BRS in untreated and Nile-treated SHR. Multiple-regression analysis showed that decrease in left ventricular and aortic hypertrophy was mainly related to the decrease in systolic BPV, and amelioration in renal lesion was mainly determined by increase in BRS. Long-term treatment with Nile possessed obvious organ protection in SHR. Besides the BP reduction, the decrease in BPV and the restoration of BRS may importantly contribute to this organ protection.
Methamphetamine-associated cardiomyopathy: patterns and predictors of recovery.
Voskoboinik, A; Ihle, J F; Bloom, J E; Kaye, D M
2016-06-01
Methamphetamine abuse is a growing public health problem, and increasing numbers of patients are admitted with methamphetamine-associated cardiomyopathy (MAC). We sought to characterise the patterns of this disease and identify predictors of recovery. We retrospectively studied consecutive patients diagnosed with MAC between January 2006 and July 2015. We identified 20 patients (14 males, 6 females) with mean age 35 ± 9 years. Most had very severe systolic dysfunction (mean left ventricular ejection fraction (LVEF) 19.7 ± 11.4%) at presentation with 14 requiring inotropes and 5 requiring mechanical support. The pattern of systolic dysfunction was global in 14 patients, while 6 patients had a 'reverse Takotsubo' (RT) pattern with severely hypokinetic basal-mid segments and apical preservation. RT patients were predominantly female, had a short history of methamphetamine abuse and had higher cardiac enzyme levels. Patients with global dysfunction tended to have mid-wall fibrosis on cardiac magnetic resonance imaging. On follow-up transthoracic echocardiography, 6 out of 19 (32%) had normalisation of LVEF (LVEF ≥ 50%) within 6 weeks. Smaller left ventricular and left atrial size, shorter duration of methamphetamine use and RT pattern appeared to predict early recovery. A subset of MAC patients, particularly those with a RT pattern and lesser ventricular dilatation have the potential for early recovery of ventricular function. By contrast, those with evidence of myocardial fibrosis and ventricular enlargement have limited scope for recovery. © 2016 Royal Australasian College of Physicians.
Mechanisms of right heart disease in pulmonary hypertension (2017 Grover Conference Series).
Asosingh, Kewal; Erzurum, Serpil
2018-01-01
Current dogma is that pathological hypertrophy of the right ventricle is a direct consequence of pulmonary vascular remodeling. However, progression of right ventricle dysfunction is not always lung-dependent. Increased afterload caused by pulmonary vascular remodeling initiates the right ventricle hypertrophy, but determinants leading to adaptive or maladaptive hypertrophy and failure remain unknown. Ischemia in a hypertrophic right ventricle may directly contribute to right heart failure. Rapidly enlarging cardiomyocytes switch from aerobic to anaerobic energy generation resulting in cell growth under relatively hypoxic conditions. Cardiac muscle reacts to an increased afterload by over-activation of the sympathetic system and uncoupling and downregulation of β-adrenergic receptors. Recent studies suggest that β blocker therapy in PH is safe, well tolerated, and preserves right ventricle function and cardiac output by reducing right ventricular glycolysis. Fibrosis, an evolutionary conserved process in host defense and wound healing, is dysregulated in maladaptive cardiac tissue contributing directly to right ventricle failure. Despite several mechanisms having been suggested in right heart disease, the causes of maladaptive cardiac remodeling remain unknown and require further research.
MicroRNA-327 regulates cardiac hypertrophy and fibrosis induced by pressure overload.
Ji, Yue; Qiu, Ming; Shen, Yejiao; Gao, Li; Wang, Yaqing; Sun, Wei; Li, Xinli; Lu, Yan; Kong, Xiangqing
2018-04-01
MicroRNA (miRNA/miR) dysregulation has been reported to be fundamental in the development and progression of cardiac hypertrophy and fibrosis. In the present study, miR-327 levels in fibroblasts were increased in response to cardiac hypertrophy induced by transverse aortic constriction with prominent cardiac fibrosis, particularly when compared with the levels in unstressed cardiomyocytes. In neonatal rat cardiac fibroblasts, induced expression of miR-327 upregulated fibrosis-associated gene expression and activated angiotensin II-induced differentiation into myofibroblasts, as assessed via α-smooth muscle actin staining. By contrast, miR-327 knockdown mitigated angiotensin II-induced differentiation. Cardiac fibroblast proliferation was not affected under either condition. In a mouse model subjected to transverse aortic constriction, miR-327 knockdown through tail-vein injection reduced the development of cardiac fibrosis and ventricular dysfunction. miR-327 was demonstrated to target integrin β3 and diminish the activation of cardiac fibroblasts. Thus, the present study supports the use of miR-327 as a therapeutic target in the reduction of cardiac fibrosis.
Sechi, Annalisa; Nucifora, Gaetano; Piccoli, Gianluca; Dardis, Andrea; Bembi, Bruno
2014-07-16
Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) imaging is increasingly used to assess myocardial involvement in patients with Fabry disease, an X linked lipid storage disorder. However, it is often proposed as an optional tool. A different cardiomyopathic disease progression between male and female patients was hypothesised in previous studies, as in female myocardial fibrosis was found without left ventricular (LV) hypertrophy, while myocardial fibrosis was always detected in association to LV hypertrophy in men. A male Caucasian patient, 19 years old, diagnosed through a family-based molecular screening, presented with LGE of the LV inferolateral wall evidenced at the CMR, without LV hypertrophy, or other clinical signs of the disease. This is the first report of cardiac fibrosis as the first sign of organ involvement in a male patient with Fabry disease. This finding stresses the importance of performing CMR with LGE imaging for the initial staging and monitoring of Fabry patients of both genders.
2014-01-01
Background Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) imaging is increasingly used to assess myocardial involvement in patients with Fabry disease, an X linked lipid storage disorder. However, it is often proposed as an optional tool. A different cardiomyopathic disease progression between male and female patients was hypothesised in previous studies, as in female myocardial fibrosis was found without left ventricular (LV) hypertrophy, while myocardial fibrosis was always detected in association to LV hypertrophy in men. Case presentation A male Caucasian patient, 19 years old, diagnosed through a family-based molecular screening, presented with LGE of the LV inferolateral wall evidenced at the CMR, without LV hypertrophy, or other clinical signs of the disease. Conclusion This is the first report of cardiac fibrosis as the first sign of organ involvement in a male patient with Fabry disease. This finding stresses the importance of performing CMR with LGE imaging for the initial staging and monitoring of Fabry patients of both genders. PMID:25026990
Tetralogy of Fallot and atrial septal defect in a white Bengal Tiger cub (Panthera tigris tigris)
2014-01-01
A 3-week-old female white Bengal Tiger cub (Panthera tigris tigris) presented with acute onset tachypnoea, cyanosis and hypothermia. The cub was severely hypoxaemic with a mixed acid–base disturbance. Echocardiography revealed severe pulmonic stenosis, right ventricular hypertrophy, high membranous ventricular septal defect and an overriding aorta. Additionally, an atrial septal defect was found on necropsy, resulting in the final diagnosis of Tetralogy of Fallot with an atrial septal defect (a subclass of Pentalogy of Fallot). This report is the first to encompass arterial blood gas analysis, thoracic radiographs, echocardiography and necropsy findings in a white Bengal Tiger cub diagnosed with Tetralogy of Fallot with an atrial septal defect. PMID:24594084
Newman, Mackenzie S; Nguyen, Tina; Watson, Michael J; Hull, Robert W; Yu, Han-Gang
2017-07-01
How obesity or sex may affect the gene expression profiles of human cardiac hypertrophy is unknown. We hypothesized that body-mass index (BMI) and sex can affect gene expression profiles of cardiac hypertrophy. Human heart tissues were grouped according to sex (male, female), BMI (lean<25 kg/m 2 , obese>30 kg/m 2 ), or left ventricular hypertrophy (LVH) and non-LVH nonfailed controls (NF). We identified 24 differentially expressed (DE) genes comparing female with male samples. In obese subgroup, there were 236 DE genes comparing LVH with NF; in lean subgroup, there were seven DE genes comparing LVH with NF. In female subgroup, we identified 1,320 significant genes comparing LVH with NF; in male subgroup, there were 1,383 significant genes comparing LVH with NF. There were seven significant genes comparing obese LVH with lean NF; comparing male obese LVH with male lean NF samples we found 106 significant genes; comparing female obese LVH with male lean NF, we found no significant genes. Using absolute value of log 2 fold-change > 2 or extremely small P value (10 -20 ) as a criterion, we identified nine significant genes (HBA1, HBB, HIST1H2AC, GSTT1, MYL7, NPPA, NPPB, PDK4, PLA2G2A) in LVH, also found in published data set for ischemic and dilated cardiomyopathy in heart failure. We identified a potential gene expression signature that distinguishes between patients with high BMI or between men and women with cardiac hypertrophy. Expression of established biomarkers atrial natriuretic peptide A (NPPA) and B (NPPB) were already significantly increased in hypertrophy compared with controls. Copyright © 2017 the American Physiological Society.
Willey, Christopher D; Palanisamy, Arun P; Johnston, Rebecca K; Mani, Santhosh K; Shiraishi, Hirokazu; Tuxworth, William J; Zile, Michael R; Balasubramanian, Sundaravadivel; Kuppuswamy, Dhandapani
2008-06-27
Growth, survival and cytoskeletal rearrangement of cardiomyocytes are critical for cardiac hypertrophy. Signal transducer and activator of transcription-3 (STAT3) activation is an important cardioprotective factor associated with cardiac hypertrophy. Although STAT3 activation has been reported via signaling through Janus Kinase 2 (JAK2) in several cardiac models of hypertrophy, the importance of other nonreceptor tyrosine kinases (NTKs) has not been explored. Utilizing an in vivo feline right ventricular pressure-overload (RVPO) model of hypertrophy, we demonstrate that in 48 h pressure-overload (PO) myocardium, STAT3 becomes phosphorylated and redistributed to detergent-insoluble fractions with no accompanying JAK2 activation. PO also caused increased levels of phosphorylated STAT3 in both cytoplasmic and nuclear fractions. To investigate the role of other NTKs, we used our established in vitro cell culture model of hypertrophy where adult feline cardiomyocytes are embedded three-dimensionally (3D) in type-I collagen and stimulated with an integrin binding peptide containing an Arg-Gly-Asp (RGD) motif that we have previously shown to recapitulate the focal adhesion complex (FAC) formation of 48 h RVPO. RGD stimulation of adult cardiomyocytes in vitro caused both STAT3 redistribution and activation that were accompanied by the activation and redistribution of c-Src and the TEC family kinase, BMX, but not JAK2. However, infection with dominant negative c-Src adenovirus was unable to block RGD-stimulated changes on either STAT3 or BMX. Further analysis in vivo in 48 h PO myocardium showed the presence of both STAT3 and BMX in the detergent-insoluble fraction with their complex formation and phosphorylation. Therefore, these studies indicate a novel mechanism of BMX-mediated STAT3 activation within a PO model of cardiac hypertrophy that might contribute to cardiomyocyte growth and survival.
Tateishi, Atsushi; Matsushita, Masayuki; Asai, Tomohiro; Masuda, Zenichi; Kuriyama, Mitsuhito; Kanki, Kazushige; Ishino, Kozo; Kawada, Masaaki; Sano, Shunji; Matsui, Hideki
2010-06-01
A large number of diverse signaling molecules in cell and animal models participate in the stimulus-response pathway through which the hypertrophic growth of the myocardium is controlled. However, the mechanisms of signaling pathway including the influence of lithium, which is known as an inhibitor of glycogen synthase kinase-3beta, in pressure overload hypertrophy remain unclear. The aim of our study was to determine whether glycogen synthase kinase-3beta inhibition by lithium has acute effects on the myocyte growth mechanism in a pressure overload rat model. First, we created a rat model of acute pressure overload cardiac hypertrophy by abdominal aortic banding. Protein expression time courses for beta-catenin, glycogen synthase kinase-3beta, and phosphoserine9-glycogen synthase kinase-3beta were then examined. The rats were divided into four groups: normal rats with or without lithium administration and pressure-overloaded rats with or without lithium administration. Two days after surgery, Western blot analysis of beta-catenin, echo-cardiographic evaluation, left ventricular (LV) weight, and LV atrial natriuretic peptide mRNA levels were evaluated. We observed an increase in the level of glycogen synthase kinase-3beta phosphorylation on Ser 9. A significant enhancement of LV heart weight (P < 0.05) and interventricular septum and posterior wall thickness (P < 0.05) with pressure-overloaded hypertrophy in animals treated with lithium were also observed. Atrial natriuretic peptide mRNA levels were significantly increased with pressure overload hypertrophy in animals treated with lithium. We have shown in an animal model that inhibition of glycogen synthase kinase-3beta by lithium has an additive effect on pressure overload cardiac hypertrophy.
Podesser, Bruno K; Kreibich, Maximilian; Dzilic, Elda; Santer, David; Förster, Lorenz; Trojanek, Sandra; Abraham, Dietmar; Krššák, Martin; Klein, Klaus U; Tretter, Eva V; Kaun, Christoph; Wojta, Johann; Kapeller, Barbara; Gonçalves, Inês Fonseca; Trescher, Karola; Kiss, Attila
2018-04-01
Left ventricular (LV) hypertrophy is characterized by cardiomyocyte hypertrophy and interstitial fibrosis ultimately leading to increased myocardial stiffness and reduced contractility. There is substantial evidence that the altered expression of matrix metalloproteinases (MMP) and Tenascin-C (TN-C) are associated with the progression of adverse LV remodeling. However, the role of TN-C in the development of LV hypertrophy because of chronic pressure overload as well as the regulatory role of TN-C on MMPs remains unknown. In a knockout mouse model of TN-C, we investigated the effect of 10 weeks of pressure overload using transverse aortic constriction (TAC). Cardiac function was determined by magnetic resonance imaging. The expression of MMP-2 and MMP-9, CD147 as well as myocardial fibrosis were assessed by immunohistochemistry. The expression of TN-C was assessed by RT-qPCR and ELISA. TN-C knockout mice showed marked reduction in fibrosis (P < 0.001) and individual cardiomyocytes size (P < 0.01), in expression of MMP-2 (P < 0.05) and MMP-9 (P < 0.001) as well as preserved cardiac function (P < 0.01) in comparison with wild-type mice after 10 weeks of TAC. In addition, CD147 expression was markedly increased under pressure overload (P < 0.01), irrespectively of genotype. TN-C significantly increased the expression of the markers of hypertrophy such as ANP and BNP as well as MMP-2 in H9c2 cells (P < 0.05, respectively). Our results are pointed toward a novel signaling mechanism that contributes to LV remodeling via MMPs upregulation, cardiomyocyte hypertrophy as well as myocardial fibrosis by TN-C under chronic pressure overload.
Alvin, Zikiar V; Laurence, Graham G; Coleman, Bernell R; Zhao, Aiqiu; Hajj-Moussa, Majd; Haddad, Georges E
2011-07-01
Early development of cardiac hypertrophy may be beneficial but sustained hypertrophic activation leads to myocardial dysfunction. Regulation of the repolarizing currents can be modulated by the activation of humoral factors, such as angiotensin II (ANG II) through protein kinases. The aim of this work is to assess the regulation of IK and IK1 by ANG II through the PI3-K pathway in hypertrophied ventricular myocytes. Cardiac eccentric hypertrophy was induced through volume-overload in adult male rats by aorto-caval shunt (3 weeks). After one week half of the rats were given captopril (2 weeks; 0.5 g/l/day) and the other half served as control. The voltage-clamp and western blot techniques were used to measure the delayed outward rectifier potassium current (IK) and the instantaneous inward rectifier potassium current (IK1) and Akt activity, respectively. Hypertrophied cardiomyocytes showed reduction in IK and IK1. Treatment with captopril alleviated this difference seen between sham and shunt cardiomyocytes. Acute administration of ANG II (10-6M) to cardiocytes treated with captopril reduced IK and IK1 in shunts, but not in sham. Captopril treatment reversed ANG II effects on IK and IK1 in a PI3-K-independent manner. However in the absence of angiotensin converting enzyme inhibition, ANG II increased both IK and IK1 in a PI3-K-dependent manner in hypertrophied cardiomyocytes. Thus, captopril treatment reveals a negative effect of ANG II on IK and IK1, which is PI3-K independent, whereas in the absence of angiotensin converting enzyme inhibition IK and IK1 regulation is dependent upon PI3-K.
Myocardial myostatin in spontaneously hypertensive rats with heart failure.
Damatto, R L; Lima, A R R; Martinez, P F; Cezar, M D M; Okoshi, K; Okoshi, M P
2016-07-15
Myostatin has been shown to regulate skeletal and cardiac muscle growth. However, its status on long-term hypertrophied myocardium has not been addressed. The purpose of this study was to evaluate the expression of myocardial myostatin and its antagonist follistatin in spontaneously hypertensive rats (SHR) with heart failure. Eighteen-month-old SHR were evaluated to identify clinical features of heart failure such as tachypnea/labored respiration and weight loss. After heart failure was detected, rats were subjected to echocardiogram and euthanized. Age-matched normotensive Wistar-Kyoto (WKY) rats were used as controls. Myostatin and follistatin protein expression was assessed by Western blotting. Statistical analysis was performed by Student's t test. All SHR (n=8) presented right ventricular hypertrophy and five had lung congestion. SHR had left chambers hypertrophy and dilation (left atrial diameter: WKY 5.73±0.59; SHR 7.28±1.17mm; p=0.004; left ventricular (LV) diastolic diameter/body weight ratio: WKY 19.6±3.1; SHR 27.7±4.7mm/kg; p=0.001), and LV systolic dysfunction (midwall fractional shortening: WKY 34.9±3.31; SHR 24.8±3.20%; p=0.003). Myocyte diameter (WKY 23.1±1.50, SHR 25.5±1.33μm; p=0.004) and myocardial interstitial collagen fraction (WKY 4.86±0.01; SHR 8.36±0.02%; p<0.001) were increased in the SHR. Myostatin (WKY 1.00±0.16; SHR 0.77±0.23 arbitrary units; p=0.035) and follistatin (WKY 1.00±0.35; SHR 0.49±0.18 arbitrary units; p=0.002) expression was lower in SHR. Myostatin and follistatin expression negatively correlated with LV diastolic diameter-to-body weight ratio and LV systolic diameter, and positively correlated with midwall fractional shortening. Myostatin and follistatin protein expression is reduced in the long-term hypertrophied myocardium from spontaneously hypertensive rats with heart failure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Hypertrophic response to hemodynamic overload: role of load vs. renin-angiotensin system activation
NASA Technical Reports Server (NTRS)
Koide, M.; Carabello, B. A.; Conrad, C. C.; Buckley, J. M.; DeFreyte, G.; Barnes, M.; Tomanek, R. J.; Wei, C. C.; Dell'Italia, L. J.; Cooper, G. 4th;
1999-01-01
Myocardial hypertrophy is one of the basic mechanisms by which the heart compensates for hemodynamic overload. The mechanisms by which hemodynamic overload is transduced by the cardiac muscle cell and translated into cardiac hypertrophy are not completely understood. Candidates include activation of the renin-angiotensin system (RAS) and angiotensin II receptor (AT1) stimulation. In this study, we tested the hypothesis that load, independent of the RAS, is sufficient to stimulate cardiac growth. Four groups of cats were studied: 14 normal controls, 20 pulmonary artery-banded (PAB) cats, 7 PAB cats in whom the AT1 was concomitantly and continuously blocked with losartan, and 8 PAB cats in whom the angiotensin-converting enzyme (ACE) was concomitantly and continuously blocked with captopril. Losartan cats had at least a one-log order increase in the ED50 of the blood pressure response to angiotensin II infusion. Right ventricular (RV) hypertrophy was assessed using the RV mass-to-body weight ratio and ventricular cardiocyte size. RV hemodynamic overload was assessed by measuring RV systolic and diastolic pressures. Neither the extent of RV pressure overload nor RV hypertrophy that resulted from PAB was affected by AT1 blockade with losartan or ACE inhibition with captopril. RV systolic pressure was increased from 21 +/- 3 mmHg in normals to 68 +/- 4 mmHg in PAB, 65 +/- 5 mmHg in PAB plus losartan and 62 +/- 3 mmHg in PAB plus captopril. RV-to-body weight ratio increased from 0.52 +/- 0.04 g/kg in normals to 1.11 +/- 0.06 g/kg in PAB, 1.06 +/- 0.06 g/kg in PAB plus losartan and 1.06 +/- 0.06 g/kg in PAB plus captopril. Thus 1) pharmacological modulation of the RAS with losartan and captopril did not change the extent of the hemodynamic overload or the hypertrophic response induced by PAB; 2) neither RAS activation nor angiotensin II receptor stimulation is an obligatory and necessary component of the signaling pathway that acts as an intermediary coupling load to the hypertrophic response; and 3) load, independent of the RAS, is capable of stimulating cardiac growth.
Wong, Weng-Yew; Poudyal, Hemant; Ward, Leigh C.; Brown, Lindsay
2012-01-01
Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrease blood glucose and glycated haemoglobin concentrations, normalise blood pressure in vivo and inhibit adipogenesis in vitro, yet their role in the metabolic syndrome has not been investigated. In this study, we investigated the effects of palm tocotrienol-rich fraction (TRF) on high carbohydrate, high fat diet-induced metabolic, cardiovascular and liver dysfunction in rats. Rats fed a high carbohydrate, high fat diet for 16 weeks developed abdominal obesity, hypertension, impaired glucose and insulin tolerance with increased ventricular stiffness, lower systolic function and reduced liver function. TRF treatment improved ventricular function, attenuated cardiac stiffness and hypertension, and improved glucose and insulin tolerance, with reduced left ventricular collagen deposition and inflammatory cell infiltration. TRF improved liver structure and function with reduced plasma liver enzymes, inflammatory cell infiltration, fat vacuoles and balloon hepatocytes. TRF reduced plasma free fatty acid and triglyceride concentrations but only omental fat deposition was decreased in the abdomen. These results suggest that tocotrienols protect the heart and liver, and improve plasma glucose and lipid profiles with minimal changes in abdominal obesity in this model of human metabolic syndrome. PMID:23201770
Takahara, A; Nakamura, Y; Wagatsuma, H; Aritomi, S; Nakayama, A; Satoh, Y; Akie, Y; Sugiyama, A
2009-01-01
Background and purpose: The heart of the canine model of chronic atrioventricular block is known to have a ventricular electrical remodelling, which mimics the pathophysiology of long QT syndrome. Using this model, we explored a new pharmacological therapeutic strategy for the prevention of cardiac sudden death. Experimental approach: The L-type Ca2+ channel blocker amlodipine (2.5 mg·day−1), L/N-type Ca2+ channel blocker cilnidipine (5 mg·day−1), or the angiotensin II receptor blocker candesartan (12 mg·day−1) was administered orally to the dogs with chronic atrioventricular block for 4 weeks. Electropharmacological assessments with the monophasic action potential (MAP) recordings and blood sample analyses were performed before and 4 weeks after the start of drug administration. Key results: Amlodipine and cilnidipine decreased the blood pressure, while candesartan hardly affected it. The QT interval, MAP duration and beat-to-beat variability of the ventricular repolarization period were shortened only in the cilnidipine group, but such effects were not observed in the amlodipine or candesartan group. Plasma concentrations of adrenaline, angiotensin II and aldosterone decreased in the cilnidipine group. In contrast, plasma concentrations of angiotensin II and aldosterone were elevated in the amlodipine group, whereas in the candesartan group an increase in plasma levels of angiotensin II and a decrease in noradrenaline and adrenaline concentrations were observed. Conclusions and implications: Long-term blockade of L/N-type Ca2+ channels ameliorated the ventricular electrical remodelling in the hypertrophied heart which causes the prolongation of the QT interval. This could provide a novel therapeutic strategy for the treatment of cardiovascular diseases. PMID:19785655
Armstrong, Anderson C; Gjesdal, Ola; Almeida, André; Nacif, Marcelo; Wu, Colin; Bluemke, David A; Brumback, Lyndia; Lima, João A C
2014-01-01
Left ventricular mass (LVM) and hypertrophy (LVH) are important parameters, but their use is surrounded by controversies. We compare LVM by echocardiography and cardiac magnetic resonance (CMR), investigating reproducibility aspects and the effect of echocardiography image quality. We also compare indexing methods within and between imaging modalities for classification of LVH and cardiovascular risk. Multi-Ethnic Study of Atherosclerosis enrolled 880 participants in Baltimore city, 146 had echocardiograms and CMR on the same day. LVM was then assessed using standard techniques. Echocardiography image quality was rated (good/limited) according to the parasternal view. LVH was defined after indexing LVM to body surface area, height(1.7) , height(2.7) , or by the predicted LVM from a reference group. Participants were classified for cardiovascular risk according to Framingham score. Pearson's correlation, Bland-Altman plots, percent agreement, and kappa coefficient assessed agreement within and between modalities. Left ventricular mass by echocardiography (140 ± 40 g) and by CMR were correlated (r = 0.8, P < 0.001) regardless of the echocardiography image quality. The reproducibility profile had strong correlations and agreement for both modalities. Image quality groups had similar characteristics; those with good images compared to CMR slightly superiorly. The prevalence of LVH tended to be higher with higher cardiovascular risk. The agreement for LVH between imaging modalities ranged from 77% to 98% and the kappa coefficient from 0.10 to 0.76. Echocardiography has a reliable performance for LVM assessment and classification of LVH, with limited influence of image quality. Echocardiography and CMR differ in the assessment of LVH, and additional differences rise from the indexing methods. © 2013. This article is a U.S. Government work and is in the public domain in the USA.
Che, Xiajing; Mou, Shan; Zhang, Weiming; Zhang, Minfang; Gu, Leyi; Yan, Yucheng; Ying, Hua; Hu, Chunhua; Qian, Jiaqi; Ni, Zhaohui
2017-04-01
Objective The aim of this study was to investigate the correlation between non-dipper circadian rhythm of blood pressure (BP) and left ventricular hypertrophy (LVH) in patients with chronic kidney disease (CKD). Methods and results All 257 patients with stage 1 to 5 CKD were enrolled in the study and classified into a CKD1-3 group and a CKD4-5 group according to renal function. The parameters and circadian rhythm of BP were measured by a GE Marquette Tonoport V Eng dynamic sphygmomanometer, and cardiac structure was examined by echocardiography. The incidence of abnormal circadian BP rhythm (non-dipper rhythm) was quite high (75.4% in all enrolled patients and 71.3% in the patients with normal BP levels) in CKD patients and increased with the deterioration of renal function. Changes of cardiac structure such as LVH in patients with non-dipper BP were more distinct than in patients with dipper BP. The development of left ventricular mass index (LVMI) correlated positively with the incidence of non-dipper BP rhythm. Multiple regression analysis showed that 24-h systolic BP (β = 0.417, P < 0.01), triglycerides (TG) (β = -0.132, P = 0.007), Hb (β = -0.394, P = 0.016) and gender (β = 0.158, P = 0.039) were independent risk factors of LVMI. Conclusions The incidence of non-dipper circadian rhythm of blood pressure was quite high in CKD patients and increased with the deterioration of renal function. Non-dipper circadian rhythm of BP is closely related with LVMI.
Falkner, Bonita; DeLoach, Stephanie; Keith, Scott W; Gidding, Samuel S
2013-01-01
To examine the relative effects of high blood pressure (HBP) and obesity on left ventricular mass (LVM) among African-American adolescents; and if metabolic or inflammatory factors contribute to LVM. Using a 2 × 2 design, African-American adolescents were stratified by body mass index percentile (body mass index <95th percentile = non-obese; ≥ 95th percentile = obese) and average blood pressure (BP) (normal BP <120/80 mm Hg; HBP ≥ 120/80). Glucose, insulin, insulin resistance, lipids, and inflammatory cytokines were measured. From echocardiography measures of LVM, calculated LVM index (LVMI) ≥ 95th percentile defined left ventricular hypertrophy (LVH). Data included 301 adolescents (48% female), mean age 16.2 years, 51% obese, and 29% HBP. LVMI was highest among adolescents with both obesity and HBP. The multiplicative interaction of obesity and HBP on LVH was not significant (OR = 2.35, P = .20) but the independent additive associations of obesity and HBP with log-odds of LVH were significant; obesity OR = 3.26, P < .001; HBP OR = 2.92, P < .001. Metabolic and inflammatory risk factors were associated with obesity, but had no independent association with LVMI. Compared with those with average systolic BP (SBP) <75th percentile, adolescents with SBP from the 75th percentile to 90th percentile had higher LVMI (33.2 vs 38.7 g/m(2.7), P < .001) and greater LVH (18% vs 43%, P < .001), independent of obesity. Prevalence of LVH is highest among African-American adolescents with average BP ≥ 120/80 mm Hg and obesity. There also is an independent association of LVMI with BP, beginning at the 75th SBP percentile. Copyright © 2013 Mosby, Inc. All rights reserved.
Fan, Xiujuan; Turdi, Subat; Ford, Stephen P.; Hua, Yinan; Nijland, Mark J.; Zhu, Meijun; Nathanielsz, Peter W.; Ren, Jun
2010-01-01
Intrauterine overnutrition is associated with development of cardiovascular disease in adulthood although the underlying mechanism has not been precisely elucidated. This study evaluated the effects of maternal overnutrition on fetal cardiac morphometry and hypertrophy-related mRNA/protein expression. Multiparous ewes were fed either 150% of NRC nutrient requirements (overfed group) or 100% of NRC requirements (control group) from 60 days before mating to day 75 (D75) of gestation, when ewes were euthanized. Cardiac morphometry, histology and expression of Akt, forkhead-3a (Foxo3a), glycogen synthase kinase-3β (GSK3β), mammalian target of rapamycin (mTOR), NFATc3 and GATA4, atrial natriuretic factor (ANF), calcineurin A and caspase-8 were examined. Crown rump length, left and right ventricular free wall weights and left ventricular wall thickness were increased in D75 overnourished fetuses. H&E staining revealed irregular myofiber orientation and increased interstitial space in heart tissues from overfed group. Masson’s trichrome staining displayed myofiber hypertrophy and fascicular disarray in heart tissues from overfed group. Overfeeding significantly enhanced Foxo3a phosphorylation in both ventricles while protein expression of Akt, Foxo3a, GSK3β and caspase-8 as well as phosphorylated Akt and GSK3β in either ventricle was unaffected. Overfeeding increased left ventricular mTOR, NFATc3 (both total and phosphorylated) and calcineurin A. GATA4, pGATA4 and ANF expression were unchanged in both ventricles. Collectively, our data suggested that overfeeding during early to mid gestation (D75) leads to morphometric changes without overt pathology which may be related to elevated expression of mTOR, NFATc3, calcineurin A and phosphorylation of Foxo3a, mTOR and NFATc3. PMID:20188535
World Health Organization cardiovascular risk stratification and target organ damage.
Piskorz, D; Bongarzoni, L; Citta, L; Citta, N; Citta, P; Keller, L; Mata, L; Tommasi, A
2016-01-01
Prediction charts allow treatment to be targeted according to simple markers of cardiovascular risk; many algorithms do not recommend screening asymptomatic target organ damage which could change dramatically the assessment. To demonstrate that target organ damage is present in low cardiovascular risk hypertensive patients and it is more frequent and severe as global cardiovascular risk increases. Consecutive hypertensive patients treated at a single Latin American center. Cardiovascular risk stratified according to 2013 WHO/ISH risk prediction chart America B. Left ventricular mass assessed by Devereux method, left ventricular hypertrophy considered >95g/m(2) in women and >115g/m(2) in men. Transmitral diastolic peak early flow velocity to average septal/lateral peak early diastolic relaxation velocity (E/e' ratio) measured cut off value >13. Systolic function assessed by tissue Doppler average interventricular septum/lateral wall mitral annulus rate systolic excursion (s wave). A total of 292 patients were included of whom 159 patients (54.5%) had cardiovascular risk of <10%, 90 (30.8%) had cardiovascular risk of 10-20% and 43 (14.7%) had cardiovascular risk of >20%. Left ventricular hypertrophy was detected in 17.6% low risk patients, 27.8% in medium risk and 23.3% in high risk (p<0.05), abnormal E/e' ratio was found in 13.8%, 31.1% and 27.9%, respectively (p<0.05). Mean s wave was 8.03+8, 8.1+9 and 8.7+1cm/s for low, intermediate and high risk patients, respectively (p<0.025). Target organ damage is more frequent and severe in high risk; one over four subjects was misclassified due to the presence of asymptomatic target organ damage. Copyright © 2015 SEHLELHA. Published by Elsevier España, S.L.U. All rights reserved.
Mohammed, Selma F; Hussain, Saad; Mirzoyev, Sultan A; Edwards, William D; Maleszewski, Joseph J; Redfield, Margaret M
2015-02-10
Characterization of myocardial structural changes in heart failure with preserved ejection fraction (HFpEF) has been hindered by the limited availability of human cardiac tissue. Cardiac hypertrophy, coronary artery disease (CAD), coronary microvascular rarefaction, and myocardial fibrosis may contribute to HFpEF pathophysiology. We identified HFpEF patients (n=124) and age-appropriate control subjects (noncardiac death, no heart failure diagnosis; n=104) who underwent autopsy. Heart weight and CAD severity were obtained from the autopsy reports. With the use of whole-field digital microscopy and automated analysis algorithms in full-thickness left ventricular sections, microvascular density (MVD), myocardial fibrosis, and their relationship were quantified. Subjects with HFpEF had heavier hearts (median, 538 g; 169% of age-, sex-, and body size-expected heart weight versus 335 g; 112% in controls), more severe CAD (65% with ≥1 vessel with >50% diameter stenosis in HFpEF versus 13% in controls), more left ventricular fibrosis (median % area fibrosis, 9.6 versus 7.1) and lower MVD (median 961 versus 1316 vessels/mm(2)) than control (P<0.0001 for all). Myocardial fibrosis increased with decreasing MVD in controls (r=-0.28, P=0.004) and HFpEF (r=-0.26, P=0.004). Adjusting for MVD attenuated the group differences in fibrosis. Heart weight, fibrosis, and MVD were similar in HFpEF patients with CAD versus without CAD. In this study, patients with HFpEF had more cardiac hypertrophy, epicardial CAD, coronary microvascular rarefaction, and myocardial fibrosis than controls. Each of these findings may contribute to the left ventricular diastolic dysfunction and cardiac reserve function impairment characteristic of HFpEF. © 2014 American Heart Association, Inc.
GPER mediates the age-dependent upregulation of the myocardial endothelin system
Meyer, Matthias R.; Fredette, Natalie C.; Sharma, Geetanjali; Barton, Matthias; Prossnitz, Eric R.
2016-01-01
Aims Cardiac aging is associated with progressive structural changes and functional impairment, such as left ventricular hypertrophy, fibrosis and diastolic dysfunction. Aging also increases myocardial activity of endothelin-1 (ET-1), a multifunctional peptide with growth-promoting and pro-fibrotic activity. Because the G protein-coupled estrogen receptor (GPER) regulates vascular responsiveness to ET-1, we investigated whether GPER also plays a role in the regulation of the cardiac endothelin system with aging. Main methods Young (4 month-old) and aged (24 month-old) wild-type and Gper-deficient (Gper-/-) mice were studied. Gene expression levels of prepro-ET-1, endothelin converting enzymes ECE-1 and ECE-2, and endothelin ETA and ETB receptors were determined by qPCR in left ventricular myocardium. Key findings Aging markedly increased steady-state mRNA expression levels of ECE-1, ECE-2, ETA and ETB receptors (each p<0.001 vs. young mice). Deletion of Gper inhibited the age-dependent increase in ECE-2 and ETB receptor mRNA levels (57% and 40% reduction, respectively, each p<0.01 vs. wild-type mice), whereas gene expression of prepro-ET-1, ECE-1, or the ETA receptor was unaffected in Gper-/- mice. Significance We identified a novel regulatory mechanism through which the endogenous Gper facilitates the age-dependent increase in myocardial expression of ECE-2 and the ETB receptor, which is compatible with an activating role of GPER for the cardiac endothelin system with aging. Targeting GPER signaling by selective antagonists may therefore be considered a new therapeutic approach to reduce age-dependent increased ET-1 activity and the associated development of left ventricular hypertrophy, fibrosis and heart failure. PMID:26880534
Cardiac abnormalities in patients with mitochondrial DNA mutation 3243A>G
Majamaa-Voltti, Kirsi; Peuhkurinen, Keijo; Kortelainen, Marja-Leena; Hassinen, Ilmo E; Majamaa, Kari
2002-01-01
Background Tissues that depend on aerobic energy metabolism suffer most in diseases caused by mutations in mitochondrial DNA (mtDNA). Cardiac abnormalities have been described in many cases, but their frequency and clinical spectrum among patients with mtDNA mutations is unknown. Methods Thirty-nine patients with the 3243A>G mtDNA mutation were examined, methods used included clinical evaluation, electrocardiogram, Holter recording and echocardiography. Autopsy reports on 17 deceased subjects were also reviewed. The degree of 3243A>G mutation heteroplasmy was determined using an Apa I restriction fragment analysis. Better hearing level (BEHL0.5–4 kHz) was used as a measure of the clinical severity of disease. Results Left ventricular hypertrophy (LVH) was diagnosed in 19 patients (56%) by echocardiography and in six controls (15%) giving an odds ratio of 7.5 (95% confidence interval; 1.74–67). The dimensions of the left ventricle suggested a concentric hypertrophy. Left ventricular systolic or diastolic dysfunction was observed in 11 patients. Holter recording revealed frequent ventricular extrasystoles (>10/h) in five patients. Patients with LVH differed significantly from those without LVH in BEHL0.5–4 kHz, whereas the contribution of age or the degree of the mutant heteroplasmy in skeletal muscle to the risk of LVH was less remarkable. Conclusions Structural and functional abnormalities of the heart were common in patients with 3243A>G. The risk of LVH was related to the clinical severity of the phenotype, and to a lesser degree to age, suggesting that patients presenting with any symptoms from the mutation should also be evaluated for cardiac abnormalities. PMID:12150714
Patel, Sheila K; Restrepo, Carolina; Werden, Emilio; Churilov, Leonid; Ekinci, Elif I; Srivastava, Piyush M; Ramchand, Jay; Wai, Bryan; Chambers, Brian; O'Callaghan, Christopher J; Darby, David; Hachinski, Vladimir; Cumming, Toby; Donnan, Geoff; Burrell, Louise M; Brodtmann, Amy
2017-04-07
Cognitive impairment is common in type 2 diabetes mellitus, and there is a strong association between type 2 diabetes and Alzheimer's disease. However, we do not know which type 2 diabetes patients will dement or which biomarkers predict cognitive decline. Left ventricular hypertrophy (LVH) is potentially such a marker. LVH is highly prevalent in type 2 diabetes and is a strong, independent predictor of cardiovascular events. To date, no studies have investigated the association between LVH and cognitive decline in type 2 diabetes. The Diabetes and Dementia (D2) study is designed to establish whether patients with type 2 diabetes and LVH have increased rates of brain atrophy and cognitive decline. The D2 study is a single centre, observational, longitudinal case control study that will follow 168 adult patients aged >50 years with type 2 diabetes: 50% with LVH (case) and 50% without LVH (control). It will assess change in cardiovascular risk, brain imaging and neuropsychological testing between two time-points, baseline (0 months) and 24 months. The primary outcome is brain volume change at 24 months. The co-primary outcome is the presence of cognitive decline at 24 months. The secondary outcome is change in left ventricular mass associated with brain atrophy and cognitive decline at 24 months. The D2 study will test the hypothesis that patients with type 2 diabetes and LVH will exhibit greater brain atrophy than those without LVH. An understanding of whether LVH contributes to cognitive decline, and in which patients, will allow us to identify patients at particular risk. Australian New Zealand Clinical Trials Registry ( ACTRN12616000546459 ), date registered, 28/04/2016.
Baggish, Aaron L; Wang, Francis; Weiner, Rory B; Elinoff, Jason M; Tournoux, Francois; Boland, Arthur; Picard, Michael H; Hutter, Adolph M; Wood, Malissa J
2008-04-01
This prospective, longitudinal study examined the effects of participation in team-based exercise training on cardiac structure and function. Competitive endurance athletes (EA, n = 40) and strength athletes (SA, n = 24) were studied with echocardiography at baseline and after 90 days of team training. Left ventricular (LV) mass increased by 11% in EA (116 +/- 18 vs. 130 +/- 19 g/m(2); P < 0.001) and by 12% in SA (115 +/- 14 vs. 132 +/- 11 g/m(2); P < 0.001; P value for the compared Delta = NS). EA experienced LV dilation (end-diastolic volume: 66.6 +/- 10.0 vs. 74.7 +/- 9.8 ml/m(2), Delta = 8.0 +/- 4.2 ml/m(2); P < 0.001), enhanced diastolic function (lateral E': 10.9 +/- 0.8 vs. 12.4 +/- 0.9 cm/s, P < 0.001), and biatrial enlargement, while SA experience LV hypertrophy (posterior wall: 4.5 +/- 0.5 vs. 5.2 +/- 0.5 mm/m(2), P < 0.001) and diminished diastolic function (E' basal lateral LV: 11.6 +/- 1.3 vs. 10.2 +/- 1.4 cm/s, P < 0.001). Further, EA experienced right ventricular (RV) dilation (end-diastolic area: 1,460 +/- 220 vs. 1,650 +/- 200 mm/m(2), P < 0.001) coupled with enhanced systolic and diastolic function (E' basal RV: 10.3 +/- 1.5 vs. 11.4 +/- 1.7 cm/s, P < 0.001), while SA had no change in RV parameters. We conclude that participation in 90 days of competitive athletics produces significant training-specific changes in cardiac structure and function. EA develop biventricular dilation with enhanced diastolic function, while SA develop isolated, concentric left ventricular hypertrophy with diminished diastolic relaxation.
Panizo, A; Pardo, J; Hernández, M; Galindo, M F; Cenarruzabeitia, E; Díez, J
1995-08-01
In genetic and acquired hypertension, a structural remodeling of the nonmyocyte compartment of myocardium, including the accumulation of fibrillar collagen and other components of the extracellular matrix (ECM) within the interstitium, represents a determinant of pathologic hypertrophy that leads to ventricular dysfunction. Therefore, to evaluate the potential benefit of the angiotensin converting enzyme (ACE) inhibitor quinapril in reversing the interstitial remodeling in spontaneously hypertensive rats (SHR) with established left ventricular hypertrophy (LVH), we treated 16-week-old male SHR with oral quinapril (average dose, 10 mg/kg body weight/day) for 20 weeks. Interstitial fibrosis was determined morphometrically using an automatic image analyzer. The amount of collagen was evaluated by measuring myocardial hydroxyproline concentration. Myocardial deposition of collagen molecules (types I, III, and IV) and other ECM components (fibronectin, laminin) was analyzed by immunohistochemical techniques using specific monoclonal antibodies. The activity of ACE was measured in left ventricular tissue by a fluorometric assay. In quinapril-treated SHR compared with 36-week-old untreated SHR and age- and sex-matched Wistar-Kyoto (WKY) controls, we found 1) a lesser degree of LVH and a lesser level of blood pressure, 2) a lesser degree of interstitial fibrosis, represented by less interstitial collagen volume fraction (5.73 +/- 0.45% v 3.42 +/- 0.28%, P < .05; WKY, 3.44 +/- 0.66%), 3) a lower hydroxyproline concentration (1.09 +/- 0.05 mumol/L/g dry weight/100 g body weight to 0.81 +/- 0.05 mumol/L/g dry weight/100 g body weight, P < .05; WKY, 0.96 +/- 0.06 mumol/L/g dry weight/100 g body weight), 4) a lesser presence of collagen fibers, and 5) a lesser presence of collagen IV, fibronectin, and laminin.(ABSTRACT TRUNCATED AT 250 WORDS)
Yang, Yan; Zhu, Li-Min; Xu, Jian-Zhong; Tang, Xiao-Feng; Gao, Ping-Jin
2017-03-01
Primary aldosteronism (PA) is the most common secondary cause of hypertension. The present study investigated differences in left ventricular structure and function between hypertensive patients with PA and sucjects with essential hypertension (EH). One hundred patients with PA and 100 controls with EH were matched for age, gender, and 24-h ambulatory monitoring blood pressure (BP). Left ventricular mass index (LVMI), left atrial volume index (LAVI) and ejection fraction were calculated. LV diastolic function was estimated as the ratio of the early diastolic velocities (E) from transmitral inflow to the early diastolic velocities (e') of tissue Doppler at mitral annulus. PA and EH patients had similar LV dimensions, LV wall thicknesses, LVMI and LV systolic function. PA was associated with greater impairment in diastolic function, as reflected by the lower e' (P=0.004), higher E/e' ratio (P=0.005) and higher LAVI (P=0.02). The LV geometric dimensions and patterns of LV hypertrophy were similar between male patients from the PA and EH groups. However, in female patients, PA was correlated with higher LV internal dimensions (P=0.001), higher LVMI (P=0.04) and lower relative wall thickness (RWT, P=0.001). Multivariate analysis showed that LV diastolic function was independently correlated with age (β=0.416, P<0.001), 24-h systolic BP (β=0.238, P=0.016) and serum potassium (β=-0.201, P=0.036) in PA patients. In conclusion, PA appears to contribute to the impairment of LV diastolic function in both sexes as well as the higher prevalence of eccentric hypertrophy in women than in men compared with EH. Age, 24-h systolic BP and serum potassium levels are independent risk factors for LV diastolic function in PA patients.
De Marchi, Stefano; Seiler, Christian; Brugger, Nicolas; Eser, Prisca
2018-01-01
Background Long-term endurance sport practice leads to eccentric left ventricular hypertrophy (LVH). We aimed to compare the new 4-tiered classification (4TC) for LVH with the established 2-tiered classification (2TC) in a cohort of normotensive non-elite endurance athletes. Methods Male participants of a 10-mile race were recruited and included when blood pressure (BP) was normal (<140/90 mmHg). Phenotypic characterization of LVH was based on relative wall thickness (2TC), and on LV concentricity2/3 (LV mass/end-diastolic volume [LVM/EDV]2/3) plus LVEDV index (4TC). Parameters of LV geometry, BP, cumulative training hours, and race time were compared between 2TC and 4TC by analysis of variance, and post-hoc analysis. Results Of 198 athletes recruited, 174 were included. Mean age was 41.6±7.5 years. Forty-two (24%) athletes had LVH. Allocation in the 2TC was: 32 (76%) eccentric LVH and 10 (24%) concentric LVH. Using the 4TC 12 were reclassified to concentric LVH, and 2 to eccentric LVH, resulting in 22 (52%) eccentric LVH (7 non-dilated, 15 dilated), and 20 (48%) concentric LVH (all non-dilated). Based on the 2TC, markers of endurance training did not differ between eccentric and concentric LVH. Based on the 4TC, athletes with eccentric LVH had more cumulative training hours and faster race times, with highest values thereof in athletes with eccentric dilated LVH. Conclusions In our cohort of normotensive endurance athletes, the new 4TC demonstrated a superior discrimination of exercise-induced LVH patterns, compared to the established 2TC, most likely because it takes three-dimensional information of the ventricular geometry into account. PMID:29462182
Contribution of reactive oxygen species to the pathogenesis of pulmonary arterial hypertension
Naik, Jay S.; Weise-Cross, Laura; Detweiler, Neil D.; Herbert, Lindsay M.; Yellowhair, Tracylyn R.; Resta, Thomas C.
2017-01-01
Pulmonary arterial hypertension is associated with a decreased antioxidant capacity. However, neither the contribution of reactive oxygen species to pulmonary vasoconstrictor sensitivity, nor the therapeutic efficacy of antioxidant strategies in this setting are known. We hypothesized that reactive oxygen species play a central role in mediating both vasoconstrictor and arterial remodeling components of severe pulmonary arterial hypertension. We examined the effect of the chemical antioxidant, TEMPOL, on right ventricular systolic pressure, vascular remodeling, and enhanced vasoconstrictor reactivity in both chronic hypoxia and hypoxia/SU5416 rat models of pulmonary hypertension. SU5416 is a vascular endothelial growth factor receptor antagonist and the combination of chronic hypoxia/SU5416 produces a model of severe pulmonary arterial hypertension with vascular plexiform lesions/fibrosis that is not present with chronic hypoxia alone. The major findings from this study are: 1) compared to hypoxia alone, hypoxia/SU5416 exposure caused more severe pulmonary hypertension, right ventricular hypertrophy, adventitial lesion formation, and greater vasoconstrictor sensitivity through a superoxide and Rho kinase-dependent Ca2+ sensitization mechanism. 2) Chronic hypoxia increased medial muscularization and superoxide levels, however there was no effect of SU5416 to augment these responses. 3) Treatment with TEMPOL decreased right ventricular systolic pressure in both hypoxia and hypoxia/SU5416 groups. 4) This effect of TEMPOL was associated with normalization of vasoconstrictor responses, but not arterial remodeling. Rather, medial hypertrophy and adventitial fibrotic lesion formation were more pronounced following chronic TEMPOL treatment in hypoxia/SU5416 rats. Our findings support a major role for reactive oxygen species in mediating enhanced vasoconstrictor reactivity and pulmonary hypertension in both chronic hypoxia and hypoxia/SU5416 rat models, despite a paradoxical effect of antioxidant therapy to exacerbate arterial remodeling in animals with severe pulmonary arterial hypertension in the hypoxia/SU5416 model. PMID:28666030
Catena, Cristiana; Verheyen, Nicolas D; Url-Michitsch, Marion; Kraigher-Krainer, Elisabeth; Colussi, GianLuca; Pilz, Stefan; Tomaschitz, Andreas; Pieske, Burkert; Sechi, Leonardo A
2016-03-01
Left ventricular hypertrophy (LVH) is an independent risk factor for cardiovascular morbidity in hypertension. Current evidence suggests a contribution to LVH of plasma aldosterone levels that are inappropriately elevated for the salt status. The aim of this study was to investigate whether inappropriate modulation of aldosterone production by a saline load is associated with left ventricular (LV) mass in hypertensive patients. In 90 hypertensive patients free of clinically relevant cardiovascular complications in whom secondary forms of hypertension were ruled out, we performed a standard intravenous saline load (0.9% NaCl, 2 l in 4 hours) with measurement of plasma aldosterone and active renin at baseline and end of infusion. Bi-dimensional echocardiography was performed for the assessment of cardiac morphology and function. LVH was present in 19% of patients who had significantly worse renal function and higher body mass, blood pressure, and plasma aldosterone levels measured both at baseline and after the saline load than patients without LVH. LV mass was directly related to age, body mass, systolic blood pressure, duration of hypertension, baseline, and post-saline load plasma aldosterone levels and inversely to glomerular filtration. Multivariate regression analysis showed independent correlation of LV mass with body mass, systolic blood pressure, and plasma aldosterone levels measured after intravenous saline load, but not at baseline. In patients with hypertension, aldosterone levels measured after intravenous saline load are related to LV mass independent of age, body mass, and blood pressure, suggesting that limited ability of salt to modulate aldosterone production could contribute to LVH. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Cariou, Eve; Bennani Smires, Youssef; Victor, Gérard; Robin, Guillaume; Ribes, David; Pascal, Pierre; Petermann, Antoine; Fournier, Pauline; Faguer, Stanislas; Roncalli, Jérôme; Rousseau, Hervé; Chauveau, Dominique; Carrié, Didier; Berry, Isabelle; Galinier, Michel; Lairez, Olivier
2017-06-01
Among diagnosis associated with left ventricular hypertrophy (LVH), cardiac amyloidosis (CA) is a progressive disease with poor prognosis. Early noninvasive identification is of growing clinical importance. The objective of our study was to integrate clinical, biologic, electrocardiographic and echocardiographic parameters to build a diagnostic score in patients with LVH. One hundred and fourteen patients with LVH underwent a cardiac magnetic resonance (CMR) and a 99m Tc-hydroxymethylene-diphosphonate scintigraphy ( 99m Tc-HMDP) allowing to discriminate three groups of diagnoses: CA (n = 50 including 31, 18 and 1 ATTR, AL and AA amyloidosis), hypertrophic cardiomyopathy (n = 19) and unspecific cardiomyopathy (n = 45). Seven continuous variables associated with CA (systolic arterial pressure <130 mmHg; PR duration >200 ms; Sokolow index <12 mV; diastolic left ventricular posterior thickness >13 mm; E/Ea ratio >10; global longitudinal strain > -12% and sum of basal longitudinal strain > -47%) were selected and dichotomized according to the best cutoff value to build the diagnostic score, which was validated in an independent cohort of 34 patients with LVH from aortic stenosis. The area under the ROC curve for the diagnosis of CA using the score was 0.933 (95%CI 0.889-0.978). The best cut off value for the score was 3 leading to a sensitivity of 90% and specificity of 81%. Area under the ROC curve for the score was 0.932 in the validation cohort. A diagnostic score >3 was associated with a poorest prognosis. An integrated evaluation of 6 diagnostic factors including arterial blood pressure, ECG and echocardiographic parameters to build a diagnostic score is a simple and easily method to discriminate the 3 main CA in patients with LVH.
Ambler, S Kelly; Hodges, Yvonne K; Jones, Gayle M; Long, Carlin S; Horwitz, Lawrence D
2008-09-01
The prolonged production of reactive oxygen species due to ischemia-reperfusion (I/R) is a potential cause of the pathological remodeling that frequently precedes heart failure. We tested the ability of a potent dithiol antioxidant, bucillamine, to protect against the long-term consequences of I/R injury in a murine model of myocardial infarction. After transiently occluding the left anterior descending coronary artery for 30 min, saline or bucillamine (10 microg/g body wt) was injected intravenously as a bolus within the first 5 min of reperfusion. The antioxidant treatment continued with daily subcutaneous injections for 4 wk. There were no differences in infarct sizes between bucillamine- and saline-treated animals. After 4 wk of reperfusion, cardiac hypertrophy was decreased by bucillamine treatment (ventricular weight-to-body weight ratios: I/R + saline, 4.5 +/- 0.2 mg/g vs. I/R + bucillamine, 4.2 +/- 0.1 mg/g; means +/- SE; P < 0.05). Additionally, the hearts of bucillamine-treated mice had improved contractile function (echocardiographic measurement of fractional shortening) relative to saline controls: I/R + saline, 32 +/- 3%, versus I/R + bucillamine, 41 +/- 4% (P < 0.05). Finally, I/R-induced injury in the saline-treated mice was accompanied by a fetal pattern of gene expression determined by ribonuclease protection assay that was consistent with pathological cardiac hypertrophy and remodeling [increased atrial natriuretic peptide, beta-myosin heavy chain (MHC), skeletal alpha-actin; decreased sarco(endo)plasmic reticulum Ca2+ ATPase 2a, and alpha-MHC-to-beta-MHC ratio]. These changes in gene expression were significantly attenuated by bucillamine. Therefore, treatment with a dithiol antioxidant for 4 wk after I/R preserved ventricular function and prevented the abnormal pattern of gene expression associated with pathological cardiac remodeling.
Relationship of MTHFR gene polymorphisms with renal and cardiac disease
Trovato, Francesca M; Catalano, Daniela; Ragusa, Angela; Martines, G Fabio; Pirri, Clara; Buccheri, Maria Antonietta; Di Nora, Concetta; Trovato, Guglielmo M
2015-01-01
AIM: To investigate the effects of different methylenetetrahydrofolate reductase (MTHFR) 677C>T gene polymorphism and hyperhomocysteinemia for the development of renal failure and cardiovascular events, which are controversial. METHODS: We challenged the relationship, if any, of MTHFR 677C>T and MTHFR 1298A>C polymorphisms with renal and heart function. The present article is a reappraisal of these concepts, investigating within a larger population, and including a subgroup of dialysis patients, if the two most common MTHFR polymorphisms, C677T and A1298C, as homozygous, heterozygous or with a compound heterozygous state, show different association with chronic renal failure requiring hemodialysis. MTHFR polymorphism could be a favorable evolutionary factor, i.e., a protective factor for many ominous conditions, like cancer and renal failure. A similar finding was reported in fatty liver disease in which it is suggested that MTHFR polymorphisms could have maintained and maintain their persistence by an heterozygosis advantage mechanism. We studied a total of 630 Italian Caucasian subject aged 54.60 ± 16.35 years, addressing to the increased hazard of hemodialysis, if any, according to the studied MTHFR genetic polymorphisms. RESULTS: A favorable association with normal renal function of MTHFR polymorphisms, and notably of MTHFR C677T is present independently of the negative effects of left ventricular hypertrophy, increased Intra-Renal arterial Resistance and hyperparathyroidism. CONCLUSION: MTHFR gene polymorphisms could have a protective role on renal function as suggested by their lower frequency among our dialysis patients in end-stage renal failure; differently, the association with left ventricular hypertrophy and reduced left ventricular relaxation suggest some type of indirect, or concurrent mechanism. PMID:25664255
Stiermaier, Thomas; Pöss, Janine; Eitel, Charlotte; de Waha, Suzanne; Fuernau, Georg; Desch, Steffen; Thiele, Holger; Eitel, Ingo
2018-05-16
Left ventricular hypertrophy (LVH) has been suggested as a determinant of outcome in patients with ST-segment elevation myocardial infarction (STEMI). However, available data are inconclusive and the underlying mechanisms remain unclear. Therefore, the aim of this study was to evaluate the impact of LVH on myocardial injury and clinical outcome in a large multicenter STEMI population. Cardiovascular magnetic resonance was performed in 795 patients within 10 days after STEMI to assess left ventricular (LV) mass and parameters of myocardial injury. Gender-specific cutoff values of indexed LV mass were used to define LVH (67 g/m 2 for men and 61 g/m 2 for women). Rates of major adverse cardiac events (MACE) were determined at 12-month follow-up. LVH was present in 438 patients (55%) and associated with a significantly larger infarct size [18.3% of LV mass (%LV) versus 14.0%LV; p < 0.01], a lower myocardial salvage index (47.8 versus 54.4; p < 0.01), larger extent of microvascular obstruction (0.4 versus 0%LV; p < 0.01) and lower LV ejection fraction (47.9 versus 53.2%; p < 0.01) compared to STEMI patients without LVH. The effect of LVH on LV ejection fraction, infarct size and myocardial salvage index remained statistically significant after adjustment for baseline characteristics (p < 0.01 for all). MACE rates at 12 months were numerically higher in patients with versus without LVH without reaching statistical significance (7.5 versus 5.6%; p = 0.32). In STEMI patients, LVH is associated with more pronounced structural and functional alterations in CMR imaging as an indicator for adverse clinical outcomes in STEMI survivors.
Sivén, Sam S E; Niiranen, Teemu J; Langén, Ville L J; Puukka, Pauli J; Kantola, Ilkka M; Jula, Antti M
2017-02-01
Electrocardiographically assessed left-ventricular hypertrophy (ECG-LVH) is a particularly high-risk phenomenon that is a part of every hypertensive patient's initial work-up. Several cross-sectional studies have demonstrated that home blood pressure (BP) has a stronger relation to LVH than office BP. However, longitudinal evidence on the association between home BP and target organ damage is scarce to nonexistent. We studied in a sample of 615 community-dwelling participants (mean age at baseline 53.7 ± 7.2, 58% women) whether change in home BP is more strongly associated with change in ECG-LVH than change in office BP over an 11-year follow-up. Pearson's correlation coefficients between changes in home/office SBP and changes in Sokolow-Lyon index, Cornell voltage, Cornell product and R wave amplitude in aVL were 0.21/0.18, 0.28/0.17, 0.25/0.16, and 0.32/0.20, respectively (asterisk indicates P < 0.05 for between-method difference in correlations with Steiger's z test). For change in home/office DBP and change in the aforementioned ECG-LVH indexes, the correlations were 0.12/0.12, 0.20/0.15, 0.16/0.12, and 0.28/0.19. Multivariable-adjusted regression modelling provided similar results. No clinically significant increase in correlations between home BP and ECG-LVH indexes occurred after the fourth day of home BP measurement. Our study demonstrates for the first time the superiority of home BP over office BP in the follow-up of left ventricular mass. The results of this and previous studies underline the importance of using out-of-office BP measurements as the primary method for assessing blood pressure levels.
Dabkowski, Erinne R; O'Connell, Kelly A; Xu, Wenhong; Ribeiro, Rogerio F; Hecker, Peter A; Shekar, Kadambari Chandra; Daneault, Caroline; Des Rosiers, Christine; Stanley, William C
2013-12-01
Supplementation with the n3 polyunsaturated fatty acid docosahexaenoic acid (DHA) is beneficial in heart failure patients, however the mechanisms are unclear. DHA is incorporated into membrane phospholipids, which may prevent mitochondrial dysfunction. Thus we assessed the effects of DHA supplementation on cardiac mitochondria and the development of heart failure caused by aortic pressure overload. Pathological cardiac hypertrophy was generated in rats by thoracic aortic constriction. Animals were fed either a standard diet or were supplemented with DHA (2.3 % of energy intake). After 14 weeks, heart failure was evident by left ventricular hypertrophy and chamber enlargement compared to shams. Left ventricle fractional shortening was unaffected by DHA treatment in sham animals (44.1 ± 1.6 % vs. 43.5 ± 2.2 % for standard diet and DHA, respectively), and decreased with heart failure in both treatment groups, but to a lesser extent in DHA treated animals (34.9 ± 1.7 %) than with the standard diet (29.7 ± 1.5 %, P < 0.03). DHA supplementation increased DHA content in mitochondrial phospholipids and decreased membrane viscosity. Myocardial mitochondrial oxidative capacity was decreased by heart failure and unaffected by DHA. DHA treatment enhanced Ca(2+) uptake by subsarcolemmal mitochondria in both sham and heart failure groups. Further, DHA lessened Ca(2+)-induced mitochondria swelling, an index of permeability transition, in heart failure animals. Heart failure increased hydrogen peroxide-induced mitochondrial permeability transition compared to sham, which was partially attenuated in interfibrillar mitochondria by treatment with DHA. DHA decreased mitochondrial membrane viscosity and accelerated Ca(2+) uptake, and attenuated susceptibility to mitochondrial permeability transition and development of left ventricular dysfunction.
Ataş, Nuh; Erten, Yasemin; Okyay, Gülay Ulusal; Inal, Salih; Topal, Salih; Öneç, Kürşad; Akyel, Ahmet; Çelik, Bülent; Tavil, Yusuf; Bali, Musa; Arınsoy, Turgay
2014-06-01
Hypertension, non-dipper blood pressure (BP) pattern and decrease in daily urine output have been associated with left ventricular hypertrophy (LVH) in peritoneal dialysis (PD) patients. However, there is lack of data regarding the impact of different PD regimens on these factors. We aimed to investigate the impact of circadian rhythm of BP on LVH in end-stage renal disease patients using automated peritoneal dialysis (APD) or continuous ambulatory peritoneal dialysis (CAPD) modalities. Twenty APD (7 men, 13 women) and 28 CAPD (16 men, 12 women) patients were included into the study. 24-h ambulatory blood pressure monitoring (ABPM) and transthoracic echocardiography besides routine blood examinations were performed. Two groups were compared with each other for ABPM measurements, BP loads, dipping patterns, left ventricular mass index (LVMI) and daily urine output. Mean systolic and diastolic BP measurements, BP loads, LVMI, residual renal function (RRF) and percentage of non-dippers were found to be similar for the two groups. There were positive correlations of LVMI with BP measurements and BP loads. LVMI was found to be significantly higher in diastolic non-dippers compared to dippers (140.4 ± 35.3 vs 114.5 ± 29.7, respectively, P = 0.02). RRF and BP were found to be independent predictors of LVMI. Non-dipping BP pattern was a frequent finding among all PD patients without an inter-group difference. Additionally, higher BP measurements, decrease in daily urine output and non-dipper diastolic BP pattern were associated with LVMI. In order to avoid LVH, besides correction of anemia and volume control, circadian BP variability and diastolic dipping should also be taken into consideration in PD patients. © 2014 The Authors. Therapeutic Apheresis and Dialysis © 2014 International Society for Apheresis.
GPER is required for the age-dependent upregulation of the myocardial endothelin system.
Meyer, Matthias R; Fredette, Natalie C; Sharma, Geetanjali; Barton, Matthias; Prossnitz, Eric R
2016-08-15
Cardiac aging is associated with progressive structural changes and functional impairment, such as left ventricular hypertrophy, fibrosis and diastolic dysfunction. Aging also increases myocardial activity of endothelin-1 (ET-1), a multifunctional peptide with growth-promoting and pro-fibrotic activity. Because the G protein-coupled estrogen receptor (GPER) regulates vascular responsiveness to ET-1, we investigated whether GPER also plays a role in the regulation of the myocardial endothelin system with aging. Young (4month-old) and aged (24month-old) wild-type and Gper-deficient (Gper(-/-)) mice were studied. Gene expression levels of prepro-ET-1, endothelin converting enzymes ECE-1 and ECE-2, and endothelin ETA and ETB receptors were determined by qPCR in left ventricular myocardium. Aging markedly increased steady-state mRNA expression levels of ECE-1, ECE-2, ETA and ETB receptors (each p<0.001 vs. young mice). Deletion of Gper inhibited the age-dependent increase in ECE-2 and ETB receptor mRNA levels (57% and 40% reduction, respectively, each p<0.01 vs. wild-type mice), whereas gene expression of prepro-ET-1, ECE-1, and the ETA receptor was unaffected in Gper(-/-) mice. We identified a novel regulatory mechanism through which the endogenous Gper facilitates the age-dependent increase in myocardial expression of ECE-2 and the ETB receptor, which is compatible with an activating role of GPER for the local endothelin system with aging. Targeting GPER signaling by selective antagonists may therefore be considered a new therapeutic approach to reduce age-dependent increased ET-1 activity and the associated development of left ventricular hypertrophy, fibrosis and heart failure. Copyright © 2016 Elsevier Inc. All rights reserved.
Tian, Jun-Ping; Wang, Hong; Tian, Xin-Kui; Du, Feng-He; Wang, Tao
2018-04-30
Background/aim: Blood pressure (BP) variability is more closely associated with adverse outcomes than ‘usual’ BP in the general population. Residual renal function (RRF) and left ventricular hypertrophy (LVH) are thought to be predictors of poor outcome in dialysis patients. However, only a few studies have focused on BP variation and its link to RRF, LVH, and outcome in peritoneal dialysis (PD) patients. Therefore, we aimed to explore the effect of visit-to-visit BP variability on RRF and LVH in continuous ambulatory PD (CAPD) patients. Materials and methods: We performed an observational study that included all prevalent PD patients between 1 February 2006 and 31 January 2007. All patients underwent BP measurements, pulse wave velocity (PWV), cardiac ultrasound, and biochemical examination during the 1-year observation. Patients were divided into the HBPV group (higher BP variability) and LBPV group (lower BP variability) based on the standard deviation of systolic BP (SBP). Results: There were 70 patients recruited for the final analysis. Patients with HBPV had a higher SBP as compared to patients with LBPV at baseline. Renal Kt/V decreased significantly from 0.50 ± 0.49 to 0.32 ± 0.35 (P < 0.01) in HBPV group (but not in the LBPV group) during follow-up. Patients with HBPV also showed a higher left ventricular mass index (LVMI) and PWV than those with LBPV at the end of follow-up. Conclusion: Our study suggests that BP variability may affect RRF in PD patients. PD patients with HBPV had a faster decline in RRF and higher PWV and LVH.
Jafary, Fahim H; Jafar, Tazeen H
2008-09-01
Indo-Asians have one of the highest rates of cardiovascular disease worldwide. Estimates and determinants of left ventricular hypertrophy (LVH) in this population are not known. We sought to determine the prevalence of and risk factors for LVH in Karachi, Pakistan. We conducted a population-based cross-sectional study on 320 randomly selected adults from the general population aged 40 years or above. LVH was defined as increased left ventricular mass index (LVMI) on echocardiogram (>115 g/m(2) in men and >95 g/m(2) in women) employing the adjusted Devereux equation. Multivariable models were built and logistic regression analysis was done for the primary outcome of LVH. Mean age of subjects was 52.7 (10.4) years, 50% were women. Mean LVMI (SD) was 72.0 (19.2) [median 71.1] g/m(2) in men and 75.7 (25.9) [median 72.9] g/m(2) in women. The overall prevalence of LVH was 21.9% in women and 2.5% in men (P < 0.001). The factors (odds ratio, 95% CI) independently associated with LVH were women versus men (11.35, 3.79-34.02), systolic blood pressure > versus
Left ventricular hypertrophy does not prevent heart failure in experimental hypertension.
Hernán Gómez Llambí, H; Cao, G; Donato, M; Suárez, D; Ottaviano, G; Müller, A; Buchholz, B; Gelpi, R; Otero-Losada, M; Milei, J
2017-07-01
Left ventricular hypertrophy (LVH) secondary to hypertension has been accepted to prevent heart failure (HF) while paradoxically increasing cardiovascular morbi-mortality. To evaluate whether antihypertensive treatment inhibits LVH, restores beta-adrenergic response and affects myocardial oxidative metabolism. Ninety spontaneously hypertensive rats (SHR) were distributed into groups and treated (mg/kg, p.o.) with: losartan 30 (L), hydralazine 11 (H), rosuvastatin 10 (R), carvedilol 20 (C). Hypertension control group comprised 18 normotensive rats (Wistar-Kyoto, WKY). Following euthanasia at 16months, contractility was measured in 50% of rats (Langendorff system) before and after isoproterenol (Iso) 10 -9 M, 10 -7 M and 10 -5 M stimulation. Left ventricular weight (LVW) was measured in the remaining hearts, and normalized by BW. Expression of thioredoxin 1 (Trx-1), peroxyredoxin 2 (Prx-2), glutaredoxin 3 (Grx-3), caspase-3 and brain natriuretic peptide (BNP) was determined. Systolic blood pressure (mmHg): 154±3 (L), 137±1 (H), 190±3 (R)*, 206±3 (SHR)*, 183±1 (C)**, and 141±1 (WKY) (*p<0.05 vs. L, H, WKY, **p<0.05 vs. L, H, WKY, SHR). LVW/BW was higher in SHR and R (p<0.05). Groups SHR, R and C evidenced baseline contractile depression. Response to Iso 10 -5 M was similar in WKY and L. Expression of Trx-1, Prx-2 and Grx-3 increased in C, H, R and L (p<0.01). Present findings argue against the traditional idea and support that LVH might not be required to prevent HF. Increased expression of thioredoxins by antihypertensive treatment might be involved in protection from HF. Copyright © 2017 Elsevier B.V. All rights reserved.
Laszlo, Roman; Kunz, Katia; Dallmeier, Dhayana; Klenk, Jochen; Denkinger, Michael; Koenig, Wolfgang; Rothenbacher, Dietrich; Steinacker, Juergen Michael
2017-10-01
The detection of left ventricular hypertrophy (LVH) is still a common objective of electrocardiography (ECG) in clinical practice. The aim of our study was to evaluate the accuracy of LVH ECG indices in people older than 65 recruited from a population-based cohort (ActiFE-Ulm study). In 432 subjects (mean age 76.2 ± 5.5 years, 51% male), left ventricular mass was echocardiographically determined (Devereux formula) and indexed (LVMI) to body surface area. Several LVH ECG indices (Lewis voltage, Gubner-Ungerleider voltage, Sokolow-Lyon voltage/product, Cornell voltage/product) were calculated with the help of resting ECG data and compared with the echocardiographic assessment. Despite echocardiographic signs of LVH [LVMI > 115 (♂) or >95 g/m 2 (♀)] in 47.5% of all subjects, diagnostic performance of all ECG indices was generally low. Magnitude of all LVH-indices was mainly predicted by frontal QRS axis in multivariate linear regression analysis. In comparison with the literature data from younger subjects, average frontal QRS axis turned counterclockwise. Most probably, age-related counterclockwise turn of frontal QRS axis is mainly explanatory for the decreased magnitude of LVH ECG indices and consecutive worse diagnostic performance of these indices in the elderly. ECG indices for detection of LVH have insufficient predictive values in geriatric subjects and should therefore not be used clinically for this purpose. Nevertheless, due to its established relevancy in cardiac risk stratification in this age group, usage of some established ECG indices might keep its significance even in the age of modern cardiac imaging.
Leigh, J Adam; O'Neal, Wesley T; Soliman, Elsayed Z
2016-06-01
Left ventricular hypertrophy (LVH) diagnosed by electrocardiography (ECG-LVH) and echocardiography (echo-LVH) are independently associated with an increased risk of cardiovascular disease (CVD) events. However, it is unknown if ECG-LVH retains its predictive properties independent of LV anatomy. We compared the risk of CVD associated with ECG-LVH and echo-LVH in 4,076 participants (41% men, 86% white) from the Cardiovascular Health Study, who were free of baseline CVD. ECG-LVH was defined with Minnesota ECG Classification criteria from baseline ECG data. Echo-LVH was defined by gender-specific LV mass values normalized to body surface area (male: >102 g/m(2); female: >88 g/m(2)). ECG-LVH was detected in 144 participants (3.5%) and echo-LVH in 430 participants (11%). Over a median follow-up of 10.6 years, 2,274 CVD events occurred. In a multivariate Cox regression analysis adjusted for common CVD risk factors, ECG-LVH (hazard ratio [HR] 1.84, 95% CI 1.51 to 2.24) and echo-LVH (HR 1.35, 95% CI 1.19 to 1.54) were associated with an increased risk for CVD events. The association between ECG-LVH and CVD events was not substantively altered with further adjustment for echo-LVH (HR 1.76, 95% CI 1.45 to 2.15). In conclusion, the association of ECG-LVH with CVD events is not dependent on echo-LVH. This finding provides support to the concept that ECG-LVH is an electrophysiological marker with predictive properties independent of LV anatomy. Copyright © 2016 Elsevier Inc. All rights reserved.
Pääkkö, Tero J W; Perkiömäki, Juha S; Kesäniemi, Y Antero; Ylitalo, Antti S; Lumme, Jarmo A; Huikuri, Heikki V; Ukkola, Olavi H
2018-03-01
Ambulatory blood pressure (ABP) has been shown to have an association with left ventricular hypertrophy (LVH). We evaluated the association between ABP characteristics and the development of LVH during long-term follow-up (20 years) in 420 middle-aged subjects from OPERA cohort. ABP measurements (ABPM) were recorded and echocardiographic examinations were performed at baseline and revisit. Anthropometrics were measured and laboratory analyses performed at visit. The questionnaire presented to all participants elicited detailed information about their habits. Left ventricular mass index (LVMI) was calculated according to Troys method. Baseline LVMI was a significant independent predictor of LVMI change (p < 0.001). None of the baseline continuous ABPM predicted the change in LVMI. A greater increase in daytime and night-time systolic blood pressure (BP) (p from 0.006 to 0.048) and 24 h, daytime and night-time pulse pressure (PP) (p from 0.005 to 0.034) predicted a greater increase in LVMI. Especially the increase in night-time SBP (p = 0.006) and PP (p = 0.005) predicted a greater increase in LVMI. We also considered circadian BP profiles among subjects, whose ABPM at baseline and echocardiographic measurements both at baseline and follow-up were available. Diastolic non-dippers were observed to show a greater increase in LVMI compared to diastolic dippers (10.6 ± 33.0 g/m 2 vs. 7.0 ± 28.8 g/m 2 , p = 0.032), when baseline LVMI and in-office DBP were taken account. These findings suggest that an increasing ambulatory PP increases and a diastolic non-dipping status may increase the risk for the development of LVH during later life course.
Caveolin 3-dependent loss of t-tubular ICa during hypertrophy and heart failure in mice.
Bryant, Simon M; Kong, Cherrie H T; Watson, Judy J; Gadeberg, Hanne C; James, Andrew F; Cannell, Mark B; Orchard, Clive H
2018-05-01
What is the central question of this study? Heart failure is associated with redistribution of L-type Ca 2+ current (I Ca ) away from the t-tubule membrane to the surface membrane of cardiac ventricular myocytes. However, the underlying mechanism and its dependence on severity of pathology (hypertrophy versus failure) are unclear. What is the main finding and its importance? Increasing severity of response to transverse aortic constriction, from hypertrophy to failure, was accompanied by graded loss of t-tubular I Ca and loss of regulation of I Ca by caveolin 3. Thus, the pathological loss of t-tubular I Ca , which contributes to impaired excitation-contraction coupling and thereby cardiac function in vivo, appears to be attributable to loss of caveolin 3-dependent stimulation of t-tubular I Ca . Previous work has shown redistribution of L-type Ca 2+ current (I Ca ) from the t-tubules to the surface membrane of rat ventricular myocytes after myocardial infarction. However, whether this occurs in all species and in response to other insults, the relationship of this redistribution to the severity of the pathology, and the underlying mechanism, are unknown. We have therefore investigated the response of mouse hearts and myocytes to pressure overload induced by transverse aortic constriction (TAC). Male C57BL/6 mice underwent TAC or equivalent sham operation 8 weeks before use. I Ca and Ca 2+ transients were measured in isolated myocytes, and expression of caveolin 3 (Cav3), junctophilin 2 (Jph2) and bridging integrator 1 (Bin1) was determined. C3SD peptide was used to disrupt Cav3 binding to its protein partners. Some animals showed cardiac hypertrophy in response to TAC with little evidence of heart failure, whereas others showed greater hypertrophy and pulmonary congestion. These graded changes were accompanied by graded cellular hypertrophy, t-tubule disruption, decreased expression of Jph2 and Cav3, and decreased t-tubular I Ca density, with no change at the cell surface, and graded impairment of Ca 2+ release at t-tubules. C3SD decreased I Ca density in control but not in TAC myocytes. These data suggest that the graded changes in cardiac function and size that occur in response to TAC are paralleled by graded changes in cell structure and function, which will contribute to the impaired function observed in vivo. They also suggest that loss of t-tubular I Ca is attributable to loss of Cav3-dependent stimulation of I Ca . © 2018 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.
Cytoskeletal role in protection of the failing heart by β-adrenergic blockade
Cheng, Guangmao; Kasiganesan, Harinath; Baicu, Catalin F.; Wallenborn, J. Grace; Kuppuswamy, Dhandapani
2012-01-01
Formation of a dense microtubule network that impedes cardiac contraction and intracellular transport occurs in severe pressure overload hypertrophy. This process is highly dynamic, since microtubule depolymerization causes striking improvement in contractile function. A molecular etiology for this cytoskeletal alteration has been defined in terms of type 1 and type 2A phosphatase-dependent site-specific dephosphorylation of the predominant myocardial microtubule-associated protein (MAP)4, which then decorates and stabilizes microtubules. This persistent phosphatase activation is dependent upon ongoing upstream activity of p21-activated kinase-1, or Pak1. Because cardiac β-adrenergic activity is markedly and continuously increased in decompensated hypertrophy, and because β-adrenergic activation of cardiac Pak1 and phosphatases has been demonstrated, we asked here whether the highly maladaptive cardiac microtubule phenotype seen in pathological hypertrophy is based on β-adrenergic overdrive and thus could be reversed by β-adrenergic blockade. The data in this study, which were designed to answer this question, show that such is the case; that is, β1- (but not β2-) adrenergic input activates this pathway, which consists of Pak1 activation, increased phosphatase activity, MAP4 dephosphorylation, and thus the stabilization of a dense microtubule network. These data were gathered in a feline model of severe right ventricular (RV) pressure overload hypertrophy in response to tight pulmonary artery banding (PAB) in which a stable, twofold increase in RV mass is reached by 2 wk after pressure overloading. After 2 wk of hypertrophy induction, these PAB cats during the following 2 wk either had no further treatment or had β-adrenergic blockade. The pathological microtubule phenotype and the severe RV cellular contractile dysfunction otherwise seen in this model of RV hypertrophy (PAB No Treatment) was reversed in the treated (PAB β-Blockade) cats. Thus these data provide both a specific etiology and a specific remedy for the abnormal microtubule network found in some forms of pathological cardiac hypertrophy. PMID:22081703
Gawor, Monika; Śpiewak, Mateusz; Kubik, Agata; Wróbel, Aleksandra; Lutyńska, Anna; Marczak, Magdalena; Grzybowski, Jacek
2018-05-23
Myocardial fibrosis in hypertrophic cardiomyopathy (HCM) is associated with worse clinical outcomes. The availability of circulating biomarkers of myocardial fibrosis and hypertrophy would be helpful in clinical practice. The aim of this study was to evaluate usefulness of various biomarkers of myocardial fibrosis and hypertrophy in HCM. Levels of biomarkers: soluble ST2 (sST2), galectin-3 (Gal-3), growth differentiation factor-15 (GDF-15), NT-proBNP and high-sensitivity cardiac troponin T (hs-cTnT) were measured in 60 patients with HCM. All patients underwent cardiac magnetic resonance imaging to calculate parameters of hypertrophy and fibrosis. We observed positive correlations among sST2 levels and left ventricular mass (LVM) (r = 0.32, p = 0.012), LV mass indexed for the body surface area (LVMI) (r = 0.27, p = 0.036) and maximal wall thickness (MWT) (r = 0.31, p = 0.015). No correlation was found between Gal-3 and GDF-15 levels and hypertrophy and fibrosis parameters. We observed positive correlations among hs-cTnT levels and LVM (r = 0.58, p < 0.0001), LVMI (r = 0.48, p = 0.0001), MWT (r = 0.31, p = 0.015) and late gadolinium enhancement (LGE) mass (r = 0.37, p = 0.003). There were positive correlations between NT-proBNP levels and LVM (r = 0.33, p = 0.01), LVMI (r = 0.41, p = 0.001), MWT (r = 0.42, p < 0.001) and LGE mass (r = 0.44, p < 0.001). Although no correlation between sST2 levels and myocardial fibrosis was found, sST2 may provide some additional information about hypertrophy extension. NT-proBNP and hs-cTnT are useful biomarkers in assessment of hypertrophy and fibrosis in HCM.
Combellas, I; Puigbo, J J; Acquatella, H; Tortoledo, F; Gomez, J R
1985-01-01
To study left ventricular diastolic function in Chagas's disease, simultaneous echocardiograms, phonocardiograms, and apexcardiograms were recorded in 20 asymptomatic patients with positive Chagas's serology and no signs of heart disease (group 1), 12 with Chagas's heart disease and symptoms of ventricular arrhythmia but no heart failure (group 2), 20 normal subjects (group 3), and 12 patients with left ventricular hypertrophy (group 4). The recordings were digitised to determine left ventricular isovolumic relaxation time and the rate and duration of left ventricular cavity dimension increase and wall thinning. In groups 1 and 2 (a) aortic valve closure (A2) and mitral valve opening were significantly delayed relative to minimum dimension and were associated with prolonged isovolumic relaxation, (b) left ventricular cavity size was abnormally increased during isovolumic relaxation and abnormally reduced during isovolumic contraction, and (c) peak rate of posterior wall thinning and dimension increase were significantly reduced and duration of posterior wall thinning was significantly prolonged; both of these abnormalities occurred at the onset of diastolic filling. These abnormalities were more pronounced in group 2 and were accompanied by an increase in the height of the apexcardiogram "a" wave, an indication of pronounced atrial systole secondary to end diastolic filling impairment due to reduced left ventricular distensibility. Group 4, which had an established pattern of diastolic abnormalities, showed changes similar to those in group 2; however, the delay in aortic valve closure (A2) and in mitral valve opening and the degree of dimension change were greater in the latter group. Thus early isovolumic relaxation and left ventricular abnormalities were pronounced in the patients with Chagas's heart disease and may precede systolic compromise, which may become apparent in later stages of the disease. The digitised method is valuable in the early detection of myocardial damage. Images PMID:3155954
Zhao, Linshuang; Xu, Chunyan; Xu, Jinling
2014-01-01
To explore the relationship between the autoantibodies against the β1 and AT1 receptors and left ventricular dilatation in patients with type 2 diabetes (T2DM). The autoantibodies against the β1 and angiotensin II type 1 (AT1) receptors of T2DM patients with and without hypertension were screened by ELISA. Multiple logistic regression was used to analyze the risk factors for left ventricular dilatation. The reversing effect of left ventricular dilatation was evaluated after receptor blocker treatment. The positive rates of autoantibodies against the β1 and AT1 receptors (43.0 and 44.1%, respectively) in T2DM patients with hypertension were significantly higher than those in normotensive patients (16.0 and 10.4%, respectively; all p < 0.01). Furthermore, among T2DM patients with hypertension, the positive rates (61.4 and 64.9%, respectively) in patients with left ventricular dilatation were remarkably higher than those with normal left ventricular dimensions (34.4 and 36.1%, respectively; all p < 0.01). The presence of β1 receptor antibody and AT1 receptor antibody were risk factors for left ventricular dilatation (p < 0.05). The curative effect of metoprolol tartrate and valsartan in reversing left ventricular hypertrophy in the group positive for autoantibodies was much better than in the negative group. The findings show that autoantibodies against the β1 and AT1 receptors may play a role in predicting left ventricular dilatation in T2DM patients in combination with hypertension. Metoprolol tartrate and valsartan are effective and safe in the treatment of these patients. © 2014 S. Karger AG, Basel.
Niwa, Koichiro
2017-12-01
Marfan syndrome, bicuspid aortic valve, and/or coarctation of the aorta are associated with medial abnormalities of the ascending aortic or para-coarctation aorta. Medial abnormalities in the ascending aorta are prevalent in other type of patients with a variety of CHDs such as single ventricle, persistent truncus arteriosus, transposition of the great arteries, hypoplastic left heart syndrome, and tetralogy of Fallot, encompassing a wide age range and may predispose to dilatation, aneurysm, and rapture necessitating aortic valve and root surgery. These CHDs exhibit ongoing dilatation of the aortic root and reduced aortic elasticity and increased aortic stiffness that may relate to intrinsic properties of the aortic root. These aortic dilatation and increased stiffness can induce aortic aneurysm, rapture of the aorta, and aortic regurgitation, but also provoke left ventricular hypertrophy, reduced coronary artery flow, and left ventricular failure. Therefore, a new clinical entity can be used to call this association of aortic pathophysiological abnormality, aortic dilation, and aorto-left ventricular interaction - "aortopathy".
Complete transposition of the great arteries with double outlet right ventricle in a dog.
Koo, S T; LeBlanc, N L; Scollan, K F; Sisson, D D
2016-06-01
A 2-year old intact male Collie dog presented to the cardiology service at Oregon State University for evaluation of cyanosis and suspected congenital cardiac disease. Echocardiography revealed a constellation of cardiac abnormalities including a single large vessel exiting the right ventricle with a diminutive left ventricular outflow tract, a ventricular septal defect, and marked concentric right ventricular hypertrophy with moderate right atrial dilation. Cardiac-gated computed tomography confirmed the previous anomalies in addition to supporting a diagnosis of complete transposition of the great arteries, double outlet right ventricle, and pulmonic hypoplasia with a single coronary ostium. Prominent bronchoesophageal collateral vessels were concurrently identified. Clinically, the dog was stable despite mild cyanosis that worsened with exercise; no intervention was elected at the time. This case report describes a rare combination of congenital cardiac defects and the usefulness of cardiac-gated cross-sectional imaging in the anatomic diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.
77-year-old female with syncope.
Abdelsalam, Mahmoud A; Geske, Jeffrey B
2017-02-15
A 77-year-old female was referred for evaluation of an episode of syncope while eating breakfast. There was no history of fall, syncope, prodrome, dyspnoea, chest discomfort or palpitations. Medical history was notable for hyperlipidaemia and treated hypertension. Blood pressure was 140/90 mm Hg, pulse 85 beats per minute (BPM). No murmurs were present on cardiac examination. ECG revealed normal sinus rhythm with left ventricular (LV) hypertrophy (see online supplementary figure S1). Holter monitor demonstrated rare premature ventricular complexes (<1% of beats), without heart block or ventricular tachycardia. Transthoracic echocardiogram is shown in figure 1. Which of the following is the explanation for the flow indicated by the yellow arrow? Aortic stenosisCoronary artery flow, indicative of coronary fistulaHypertrophic cardiomyopathy with apical pouchHypertensive heart diseaseMitral stenosis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
[Left auricular hypertrophy in aortic stenosis in adults].
Boschat, J; Le Mehaute, H; Le Potier, J; Roriz, R; Gilard, M; Bergez, C; Etienne, Y; Blanc, J J; Penther, P
1990-02-01
Left atrial hypertrophy (LAH) was noted from the electrocardiograms of 72 of 98 adult patients (81%) who underwent hemodynamic evaluation of calcified aortostenosis (CAS). The relations between LAH and clinical, echographic and hemodynamic findings are specified. The frequency of LAH was not higher in cases of a history of hypertension, angina pectoris, lipothymia or exercise-induced syncope. In contrast, dyspnea was more frequently associated with LAH (84%) than not (17%). An approximately linear relation was seen between LAH and the mean pulmonary capillary pressure, the mean rate of circumferential decrease (RCF), the coefficient of muscle rigidity (ks of Mirsky), the left ventricular mass (LVM) and the left ventricle-aorta gradient. LAH is, therefore, a frequent sign in patients presenting CAS. Its origin is multifactorial, with a predominance of increased mean capillary pressure in cases of clinical signs of poor safety.
Parikh, Victoria Nicole; Liu, Jing; Shang, Ching; Woods, Christopher; Chang, Alex Chia Yu; Zhao, Mingming; Charo, David N; Grunwald, Zachary; Huang, Yong; Seo, Kinya; Tsao, Philip S; Bernstein, Daniel; Ruiz-Lozano, Pilar; Quertermous, Thomas; Ashley, Euan A
2018-05-18
The G protein coupled receptor APJ is a promising therapeutic target for heart failure. Constitutive deletion of APJ in the mouse is protective against the hypertrophy-heart failure transition via elimination of ligand-independent, β-arrestin dependent stretch transduction. However, the cellular origin of this stretch transduction and the details of its interaction with apelin signaling remain unknown. We generated mice with conditional elimination of APJ in the endothelium (APJ endo-/- ) and myocardium (APJ myo-/- ). No baseline difference was observed in LV function in APJ endo-/- , APJ myo-/- or controls (APJ endo+/+ , APJ myo+/+ ). After exposure to transaortic constriction (TAC), APJ endo-/- animals developed left ventricular failure while APJ myo-/- were protected. At the cellular level, carbon fiber stretch of freshly isolated single cardiomyocytes demonstrated decreased contractile response to stretch in APJ -/- cardiomyocytes compared to APJ +/+ cardiomyocytes. Calcium transient did not change with stretch in either APJ -/- or APJ +/+ cardiomyocytes. Application of apelin to APJ +/+ cardiomyocytes resulted in decreased calcium transient. Further, hearts of mice treated with apelin exhibited decreased phosphorylation at Troponin I (cTnI) N-terminal residues (Ser 22,23), consistent with increased calcium sensitivity. These data establish that APJ stretch transduction is mediated specifically by myocardial APJ, that APJ is necessary for stretch-induced increases in contractility, and that apelin opposes APJ's stretch-mediated hypertrophy signaling by lowering calcium transient while maintaining contractility through myofilament calcium sensitization. These findings underscore apelin's unique potential as a therapeutic agent that can simultaneously support cardiac function and protect against the hypertrophy-heart failure transition.
Feng, Jun; Chen, Hua-Wen; Pi, Li-Juan; Wang, Jin; Zhan, Da-Qian
2017-01-01
The study aimed to investigate the protective effect of tanshinone IIA against cardiac hypertrophy in spontaneously hypertensive rats (SHRs) through the Cys-C/Wnt signaling pathway. Thirty SHRs were randomly divided into cardiac hypertrophy, low- and high-dose tanshinone IIA groups. Ten Wistar-Kyoto rats were selected as control group. The systolic blood pressure (SBP), heart weight (HW), left ventricular weight (LVW) and body weight (BW) of all rats were recorded. HE staining and qRT-PCR were applied to observe the morphology of myocardial tissue and mRNA expressions of COL1A1 and COL3A1. ELISA and Western blotting were used to measure the serum asymmetric dimethylarginine (ADMA), nitric oxide (NO) and cardiac troponin I (cTnI) levels, and the expressions of the Cys-C/Wnt signaling pathway-related proteins, eNOS and Nox4. Compared with the cardiac hypertrophy group, the SBP, HW/BW, LVW/BW, swelling degree of myocardial cells, COL1A1 and COL3A1 mRNA expressions, serum cTnI and ADMA levels, and the Cys-C/Wnt signaling pathway-related proteins and Nox4 expressions in the low- and high-dose tanshinone IIA groups were decreased, but the endothelial NO synthase (eNOS), phosphorylated eNOS (Ser1177) and NO expressions were increased. No significant difference was found between the low- and high-dose tanshinone IIA groups. Our study indicated a protective effect of tanshinone IIA against cardiac hypertrophy in SHRs through inhibiting the Cys-C/Wnt signaling pathway. PMID:28053285
UCP3 Ablation Exacerbates High-Salt Induced Cardiac Hypertrophy and Cardiac Dysfunction.
Lang, Hongmei; Xiang, Yang; Ai, Zhihua; You, Zhiqing; Jin, Xiaolan; Wan, Yong; Yang, Yongjian
2018-04-20
Excessive salt intake and left ventricular hypertrophy (LVH) are both critical for the development of hypertension and heart failure. The uncoupling protein 3 (UCP3) plays a cardio-protective role in early heart failure development. However, the potential role for UCP3 in salt intake and LVH is unclear. UCP3-/- and C57BL/6 mice were placed on either a normal-salt (NS, 0.5%) or a high-salt (HS, 8%) diet for 24 weeks. The cardiac function, endurance capacity, energy expenditure, and mitochondrial functional capacity were measured in each group. Elevated blood pressure was only observed in HS-fed UCP3-/- mice. High salt induced cardiac hypertrophy and dysfunction were observed in both C57BL/6 and UCP3-/- mice. However, the cardiac lesions were more profound in HS-fed UCP3-/- mice. Furthermore, HS-fed UCP3-/-mice experienced more severe mitochondrial respiratory dysfunction compared with HS-fed C57BL/6 mice, represented by the decreased volume of oxygen consumption and heat production at the whole-body level. UCP3 protein was involved in the incidence of high-salt induced hypertension and the progression of cardiac dysfunction in the early stages of heart failure. UCP3 ablation exacerbated high-salt-induced cardiac hypertrophy and cardiac dysfunction. © 2018 The Author(s). Published by S. Karger AG, Basel.
Effects of bisoprolol and losartan treatment in the hypertrophic and failing right heart.
Andersen, Stine; Schultz, Jacob Gammelgaard; Andersen, Asger; Ringgaard, Steffen; Nielsen, Jan M; Holmboe, Sarah; Vildbrad, Mads D; de Man, Frances S; Bogaard, Harm J; Vonk-Noordegraaf, Anton; Nielsen-Kudsk, Jens Erik
2014-11-01
Sympathetic adrenergic stimulation and the renin-angiotensin-aldosterone system are highly elevated in right heart failure. We evaluated if treatment with the adrenergic receptor blocker bisoprolol or the angiotensin II receptor blocker losartan could prevent the progression of right ventricular (RV) hypertrophy and failure in rats after pulmonary trunk banding (PTB). Male Wistar rats were randomized to severe PTB with a 0.5-mm banding clip (PTB0.5, n = 29), moderate PTB with a 0.6-mm banding clip (PTB0.6, n = 28), or sham operation (SHAM, n = 13). The PTB0.5 and PTB0.6 rats were randomized to 6 weeks of 10 mg/kg/d bisoprolol treatment, 20 mg/kg/d losartan treatment, or vehicle treatment. The PTB caused hypertrophy, dilation, and reduced function of the RV in all rats subjected to the procedure. Rats subjected to the more severe banding developed decompensated RV failure with extracardiac manifestations. Treatment with bisoprolol slowed the heart rate, and treatment with losartan lowered mean arterial pressure, confirming adequate dosing, but none of the treatments improved RV function or arrested the progression of RV hypertrophy and failure compared with vehicle. In our PTB model of pressure overload-induced RV hypertrophy and failure, treatment with bisoprolol and losartan did not demonstrate any beneficial effects in compensated or decompensated RV failure. Copyright © 2014 Elsevier Inc. All rights reserved.
Tang, Xilan; Gan, Xiaohong Tracey; Rajapurohitam, Venkatesh; Huang, Cathy Xiaoling; Xue, Jenny; Lui, Edmund M K; Karmazyn, Morris
2016-12-01
There is increasing evidence for a beneficial effect of ginseng on cardiac pathology. Here, we determined whether North American ginseng can modulate the deleterious effects of the β-adrenoceptor agonist isoproterenol on cardiac hypertrophy and function using in vitro and in vivo approaches. Isoproterenol was administered for 2 weeks at either 25 mg/kg per day or 50 mg/kg per day (ISO25 or ISO50) via a subcutaneously implanted osmotic mini-pump to either control rats or those receiving ginseng (0.9 g/L in the drinking water ad libitum). Isoproterenol produced time- and dose-dependent left ventricular dysfunction, although these effects were attenuated by ginseng. Improved cardiac functions were associated with reduced heart masses, as well as prevention in the upregulation of the hypertrophy-related fetal gene expression. Lung masses were similarly attenuated, suggesting reduced pulmonary congestion. In in vitro studies, ginseng (10 μg/mL) completely suppressed the hypertrophic response to 1 μmol/L isoproterenol in terms of myocyte surface area, as well as reduction in the upregulation of fetal gene expression. These effects were associated with attenuation in both protein kinase A and cAMP response element-binding protein phosphorylation. Ginseng attenuates adverse cardiac adrenergic responses and, therefore, may be an effective therapy to reduce hypertrophy and heart failure associated with excessive catecholamine production.
Heymans, Stephane; Lupu, Florea; Terclavers, Sven; Vanwetswinkel, Bjorn; Herbert, Jean-Marc; Baker, Andrew; Collen, Desire; Carmeliet, Peter; Moons, Lieve
2005-01-01
Left ventricular (LV) hypertrophy is a natural response of the heart to increased pressure loading, but accompanying fibrosis and dilatation may result in irreversible life-threatening heart failure. Matrix metalloproteinases (MMPs) have been invoked in various cardiac diseases, however, direct genetic evidence for a role of the plasminogen activator (PA) and MMP systems in pressure overload-induced LV hypertrophy and in heart failure is lacking. Therefore, the consequences of transverse aortic banding (TAB) were analyzed in mice lacking tissue-type PA (t-PA−/−), urokinase-type PA (u-PA−/−), or gelatinase-B (MMP-9−/−), and in wild-type (WT) mice after adenoviral gene transfer of the PA-inhibitor PAI-1 or the MMP-inhibitor TIMP-1. TAB elevated LV pressure comparably in all genotypes. In WT and t-PA−/− mice, cardiomyocyte hypertrophy was associated with myocardial fibrosis, LV dilatation and dysfunction, and pump failure after 7 weeks. In contrast, in u-PA−/− mice or in WT mice after PAI-1- and TIMP-1-gene transfer, cardiomyocyte hypertrophy was moderate and only minimally associated with cardiac fibrosis and LV dilatation, resulting in better preservation of pump function. Deficiency of MMP-9 had an intermediate effect. These findings suggest that the use of u-PA- or MMP-inhibitors might preserve cardiac pump function in LV pressure overloading. PMID:15631996
Suppression of Class I and II Histone Deacetylases Blunts Pressure-Overload Cardiac Hypertrophy
Kong, Yongli; Tannous, Paul; Lu, Guangrong; Berenji, Kambeez; Rothermel, Beverly A.; Olson, Eric N.; Hill, Joseph A.
2014-01-01
Background Recent work has demonstrated the importance of chromatin remodeling, especially histone acetylation, in the control of gene expression in the heart. In cell culture models of cardiac hypertrophy, pharmacological suppression of histone deacetylases (HDACs) can either blunt or amplify cell growth. Thus, HDAC inhibitors hold promise as potential therapeutic agents in hypertrophic heart disease. Methods and Results In the present investigation, we studied 2 broad-spectrum HDAC inhibitors in a physiologically relevant banding model of hypertrophy, observing dose-responsive suppression of ventricular growth that was well tolerated in terms of both clinical outcome and cardiac performance measures. In both short-term (3-week) and long-term (9-week) trials, cardiomyocyte growth was blocked by HDAC inhibition, with no evidence of cell death or apoptosis. Fibrotic change was diminished in hearts treated with HDAC inhibitors, and collagen synthesis in isolated cardiac fibroblasts was blocked. Preservation of systolic function in the setting of blunted hypertrophic growth was documented by echocardiography and by invasive pressure measurements. The hypertrophy-associated switch of adult and fetal isoforms of myosin heavy chain expression was attenuated, which likely contributed to the observed preservation of systolic function in HDAC inhibitor–treated hearts. Conclusions Together, these data suggest that HDAC inhibition is a viable therapeutic strategy that holds promise in the treatment of load-induced heart disease. PMID:16735673
Current Perspectives on Systemic Hypertension in Heart Failure with Preserved Ejection Fraction.
Tam, Marty C; Lee, Ran; Cascino, Thomas M; Konerman, Matthew C; Hummel, Scott L
2017-02-01
Heart failure with preserved ejection fraction (HFpEF) is a prevalent but incompletely understood syndrome. Traditional models of HFpEF pathophysiology revolve around systemic HTN and other causes of increased left ventricular afterload leading to left ventricular hypertrophy (LVH) and diastolic dysfunction. However, emerging models attribute the development of HFpEF to systemic proinflammatory changes secondary to common comorbidities which include HTN. Alterations in passive ventricular stiffness, ventricular-arterial coupling, peripheral microvascular function, systolic reserve, and chronotropic response occur. As a result, HFpEF is heterogeneous in nature, making it difficult to prescribe uniform therapies to all patients. Nonetheless, treating systemic HTN remains a cornerstone of HFpEF management. Antihypertensive therapies have been linked to LVH regression and improvement in diastolic dysfunction. However, to date, no therapies have definitive mortality benefit in HFpEF. Non-pharmacologic management for HTN, including dietary modification, exercise, and treating sleep disordered breathing, may provide some morbidity benefit in the HFpEF population. Future research is need to identify effective treatments, perhaps in more specific subgroups, and focus may need to shift from reducing mortality to improving exercise capacity and symptoms. Tailoring antihypertensive therapies to specific phenotypes of HFpEF may be an important component of this strategy.
Mokoli, Vieux Momeme; Sumaili, Ernest Kiswaya; Lepira, François Bompeka; Mbutiwi, Fiston Ikwa Ndol; Makulo, Jean Robert Rissassy; Bukabau, Justine Busanga; Izeidi, Patrick Parmba; Luse, Jeannine Losa; Mukendi, Stéphane Kalambay; Mashinda, Désiré Kulimba; Nseka, Nazaire Mangani
2018-03-20
Decreased residual urine volume (RUV) is associated with higher mortality in hemodialysis (HD). However, few studies have examined RUV in patients on HD in Sub-Saharan Africa. The aim of this study was to identify predictors of RUV among incident hemodialysis patients in Kinshasa. This historical cohort study enrolled 250 patients with ESRD undergoing hemodialysis between January 2007 and July 2013 in two hemodialysis centers in Kinshasa. RUV were collected over 24 h at the initiation of HD and 6 and 12 months later during the interdialytic period. We compared the baseline characteristics of the patients according to their initial RUV (≤ 500 ml/day vs > 500 ml/day) using Student's t, Mann-Whitney U and Chi2 tests. Linear mixed-effects models were used to search for predictors of decreased RUV by adding potentially predictive baseline covariates of the evolution of RUV to the effect of time: age, sex, diabetes mellitus, hypertension, diastolic blood pressure, diuretics, angiotensin conversion enzyme inhibitors (ACEI), angiotensin receptor blockers, hypovolemia, chronic tubulointerstitial nephropathy, left ventricular hypertrophy and initial hemodialysis characteristic. A value of p < 0.05 was considered the threshold of statistical significance. The majority of hemodialysis patients were male (68.8%, sex ratio 2.2), with a mean age of 52.5 ± 12.3 years. The population's RUV decreased with time, but with a slight deceleration. The mean RUV values were 680 ± 537 ml/day, 558 ± 442 ml/day and 499 ± 475 ml/day, respectively, at the initiation of HD and at 6 and 12 months later. The use of ACEI at the initiation of HD (beta coefficient 219.5, p < 0.001) and the presence of chronic tubulointerstitial nephropathy (beta coefficient 291.8, p = 0.007) were significantly associated with RUV preservation over time. In contrast, the presence of left ventricular hypertrophy at the initiation of HD was significantly associated with decreased RUV over time (beta coefficient - 133.9, p = 0.029). Among incident hemodialysis patients, the use of ACEI, the presence of chronic tubulointerstitial nephropathy and reduced left ventricular hypertrophy are associated with greater RUV preservation in the first year of dialysis.
Right Ventricular Perfusion: Physiology and Clinical Implications.
Crystal, George J; Pagel, Paul S
2018-01-01
Regulation of blood flow to the right ventricle differs significantly from that to the left ventricle. The right ventricle develops a lower systolic pressure than the left ventricle, resulting in reduced extravascular compressive forces and myocardial oxygen demand. Right ventricular perfusion has eight major characteristics that distinguish it from left ventricular perfusion: (1) appreciable perfusion throughout the entire cardiac cycle; (2) reduced myocardial oxygen uptake, blood flow, and oxygen extraction; (3) an oxygen extraction reserve that can be recruited to at least partially offset a reduction in coronary blood flow; (4) less effective pressure-flow autoregulation; (5) the ability to downregulate its metabolic demand during coronary hypoperfusion and thereby maintain contractile function and energy stores; (6) a transmurally uniform reduction in myocardial perfusion in the presence of a hemodynamically significant epicardial coronary stenosis; (7) extensive collateral connections from the left coronary circulation; and (8) possible retrograde perfusion from the right ventricular cavity through the Thebesian veins. These differences promote the maintenance of right ventricular oxygen supply-demand balance and provide relative resistance to ischemia-induced contractile dysfunction and infarction, but they may be compromised during acute or chronic increases in right ventricle afterload resulting from pulmonary arterial hypertension. Contractile function of the thin-walled right ventricle is exquisitely sensitive to afterload. Acute increases in pulmonary arterial pressure reduce right ventricular stroke volume and, if sufficiently large and prolonged, result in right ventricular failure. Right ventricular ischemia plays a prominent role in these effects. The risk of right ventricular ischemia is also heightened during chronic elevations in right ventricular afterload because microvascular growth fails to match myocyte hypertrophy and because microvascular dysfunction is present. The right coronary circulation is more sensitive than the left to α-adrenergic-mediated constriction, which may contribute to its greater propensity for coronary vasospasm. This characteristic of the right coronary circulation may increase its vulnerability to coronary vasoconstriction and impaired right ventricular perfusion during administration of α-adrenergic receptor agonists.
Chen, Bing-Hua; Wu, Rui; An, Dong-Aolei; Shi, Ruo-Yang; Yao, Qiu-Ying; Lu, Qing; Hu, Jiani; Jiang, Meng; Deen, James; Chandra, Ankush; Xu, Jian-Rong; Wu, Lian-Ming
2018-05-07
BOLD (blood oxygen level dependent) MRI can detect regional condition of myocardial oxygen supply and demand by means of paramagnetic properties. Noninvasive assessment of myocardial oxygenation by BOLD MRI in hypertensive patients with hypertension (HTN) left ventricular myocardial hypertrophy (LVMH) and HTN non-LVMH and its correlation with myocardial mechanics were performed. Prospective. Twenty patients with HTN LVMH, 21 patients with HTN non-LVMH, and 23 normotensive controls were enrolled. Cine imaging, T2* and T1 mapping sequences were achieved at 3.0T. Dedicated T1 mapping, T2*, and cine imaging analysis were performed by two radiologists using cvi42. One-way analysis of variance, Kruskal-Wallis test, Bland-Altman analysis, Pearson's correlation coefficient, Spearman's rank correlation. T2* values of HTN LVMH group were significantly lower versus the controls (23.78 ± 3.09 versus 30.77 ± 2.71; P < 0.001) and HTN non-LVMH group (23.78 ± 3.09 versus 28.64 ± 4.23; P < 0.001). Left ventricular peak circumferential strain were reduced in HTN LVMH patients compared with other two groups (-11.32 [-15.64, -10.3], -16.78 [-19.35, -15.34], and -19.73 [-20.57, -18.73]; P < 0.05); and longitudinal strain of HTN LVMH patients were lower than other two groups (-11.31 ± 2.91, -15.1 ± 3.06, and -18.85 ± 1.85; P < 0.05); radial strain of HTN LVMH patients were also lower than other two groups (25.03 ± 16, 40.95 ± 17.5 and 47.9 ± 10.23; P < 0.05). Extracellular volume correlated with peak circumferential, longitudinal, and radial strain (spearman rho = 0.6, 0.64, and -0.69; P < 0.05), respectively; T2* negatively correlated with peak circumferential and longitudinal strain (spearman rho = -0.43 and -0.49; P < 0.05), respectively. Patients with lower T2* values had significant decreases in myocardial mechanics (P < 0.05). HTN LVMH patients have both impaired myocardial mechanics and decreased T2* values compared with HTN non-LVMH and normotensive groups. BOLD MRI could provide a feasible assessment modality for detecting altered T2* due to the change of de-oxygenated hemoglobin and hence to the change of signal intensity in oxygenation-sensitive images. 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018. © 2018 International Society for Magnetic Resonance in Medicine.
Bayauli, M P; Lepira, F B; Kayembe, P K; M'buyamba-Kabangu, J R
2012-03-01
We assessed left ventricular structural alterations associated with chronic kidney disease (CKD) in Congolese patients with type 2 diabetes. This was a cross-sectional study of a case series. We obtained anthropometric, clinical, biological and echocardiographic measurements in 60 consecutive type 2 diabetes patients (37 females, 62% ) aged 20 years or older from the diabetes outpatient clinic, University of Kinshasa Hospital, DRC. We computed creatinine clearance rate according to the MDRD equation and categorised patients into mild (CrCl > 60 ml/min per 1.73 m(2)), moderate (CrCl 30-60 ml/min per 1.73 m(2)) and severe CKD (< 30 ml/min per 1.73 m(2)). Left ventricular hypertrophy (LVH) was indicated by a LV mass index (LVMI) > 51 g/m(2.7) and LV geometry was defined as normal, or with concentric remodelling, eccentric or concentric hypertrophy, using relative wall thickness (RWT) and LVMI. Compared to patients with normal kidney function, CKD patients had higher uric acid levels (450 ± 166 vs 306 ± 107 µmol/l; p ≤ 0.001), a greater proportion of LVH (37 vs 14%; p ≤ 0.05) and longstanding diabetes (13 ± 8 vs 8 ± 6 years; p ≤ 0.001). Their left ventricular internal diameter, diastolic (LVIDD) was (47.00 ± 6.00 vs 43.00 ± 7.00 mm; p ≤ 0.001), LVMI was (47 ± 19 vs 36.00 ± 15 g/m2.7; p ≤ 0.05) and proportions of concentric (22 vs 11%; p ≤ 0.05) or eccentric (15 vs 3%; p ≤ 0.05) LVH were also greater. Severe CKD was associated with increased interventricular septum, diastolic (IVSD) (12.30 ± 3.08 vs 9.45 ± 1.94 mm; p ≤ 0.05), posterior wall thickness, diastolic (PWTD) (11.61 ± 2.78 vs 9.52 ± 1.77 mm; p ≤ 0.01), relative wall thickness (RWT) (0.52 ± 0.17 vs 0.40 ± 0.07; p ≤ 0.01) rate of LVH (50 vs 30%; p ≤ 0.05), and elevated proportions of concentric remodelling (25 vs 15%; p ≤ 0.05) and concentric LVH (42 vs 10%; p ≤ 0.05) in comparison with patients with moderate CKD. In multivariable adjusted analysis, hyperuricaemia emerged as the only predictor of the presence of LVH in patients with CKD (adjusted OR 9.10; 95% CI: 2.40-33.73). In keeping with a higher rate of cardiovascular events usually reported in patients with impaired renal function, CKD patients exhibited LVH and abnormal LV geometry.
Arrhythmia as a cardiac manifestation in MELAS syndrome.
Thomas, Tamara; Craigen, William J; Moore, Ryan; Czosek, Richard; Jefferies, John L
2015-09-01
A 44-year-old female with a diagnosis of mitochondrial myopathy, encephalopathy and stroke-like episodes (MELAS) syndrome had progressive left ventricular hypertrophy (LVH) on echocardiogram. A Holter monitor demonstrated episodes of non-sustained atrial tachycardia, a finding not been previously described in this population. This unique case of MELAS syndrome demonstrates the known associated cardiac manifestation of LVH and the new finding of atrial tachycardia which may represent the potential for subclinical arrhythmia in this population.
Huang, Chun-kai; Chen, Bi-yi; Guo, Ang; Chen, Rong; Zhu, Yan-qi; Kutschke, William; Hong, Jiang; Song, Long-sheng
2016-01-01
Aim: Sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, has been shown to exert beneficial effects in heart failure. The purpose of this study was to test whether sildenafil suppressed transverse-tubule (T-tubule) remodeling in left ventricular (LV) failure and thereby providing the therapeutic benefits. Methods: A pressure overload-induced murine heart failure model was established in mice by thoracic aortic banding (TAB). One day after TAB, the mice received sildenafil (100 mg·kg−1·d−1, sc) or saline for 5 weeks. At the end of treatment, echocardiography was used to examine LV function. Then the intact hearts were dissected out and placed in Langendorff-perfusion chamber for in situ confocal imaging of T-tubule ultrastructure from epicardial myocytes. Results: TAB surgery resulted in heart failure accompanied by remarkable T-tubule remodeling. Sildenafil treatment significantly attenuated TAB-induced cardiac hypertrophy and congestive heart failure, improved LV contractile function, and preserved T-tubule integrity in LV cardiomyocytes. But sildenafil treatment did not significantly affect the chamber dilation. The integrity of LV T-tubule structure was correlated with cardiac hypertrophy (R2=0.74, P<0.01) and global LV function (R2=0.47, P<0.01). Conclusion: Sildenafil effectively ameliorates LV T-tubule remodeling in TAB mice, revealing a novel mechanism underlying the therapeutic benefits of sildenafil in heart failure. PMID:26972492
Metabolic acidosis increases fibroblast growth factor 23 in neonatal mouse bone
Culbertson, Christopher D.; Kyker-Snowman, Kelly; Bushinsky, David A.
2012-01-01
Fibroblast growth factor 23 (FGF23) significantly increases with declining renal function, leading to reduced renal tubular phosphate reabsorption, decreased 1,25-dihydroxyvitamin D, and increased left ventricular hypertrophy. Elevated FGF23 is associated with increased mortality. FGF23 is synthesized in osteoblasts and osteocytes; however, the mechanisms by which it is regulated are not clear. Patients with chronic kidney disease have decreased renal acid excretion leading to metabolic acidosis, which has a direct effect on bone cell activity. We hypothesized that metabolic acidosis would directly increase bone cell FGF23 production. Using cultured neonatal mouse calvariae, we found that metabolic acidosis increased medium FGF23 protein levels as well as FGF23 RNA expression at 24 h and 48 h compared with incubation in neutral pH medium. To exclude that the increased FGF23 was secondary to metabolic acidosis-induced release of bone mineral phosphate, we cultured primary calvarial osteoblasts. In these cells, metabolic acidosis increased FGF23 RNA expression at 6 h compared with incubation in neutral pH medium. Thus metabolic acidosis directly increases FGF23 mRNA and protein in mouse bone. If these results are confirmed in humans with chronic kidney disease, therapeutic interventions to mitigate acidosis, such as bicarbonate administration, may also lower levels of FGF23, decrease left ventricular hypertrophy, and perhaps even decrease mortality. PMID:22647635
Du, Yan; Plante, Eric; Janicki, Joseph S.; Brower, Gregory L.
2010-01-01
The temporal myocardial remodeling induced by chronic ventricular volume overload in male rats was examined. Specifically, left ventricular (LV) cardiomyocyte length and width, sarcomere length, and number of nuclei were measured in male rats (n = 8 to 17) at 1, 3, 5, 7, 21, 35, and 56 days after creation of an infrarenal aortocaval fistula. In contrast to previously published reports of progressive increases in cardiomyocyte length and cross-sectional area at 5 days post-fistula and beyond in female hearts, cardiomyocyte length and width did not increase significantly in males during the first 35 days of volume overload. Furthermore, a significant decrease in cardiomyocyte length relative to age-matched controls, together with a reduced number of sarcomeres per cell, was noted in male hearts at 5 days post-fistula. There was a concurrent increase in the percentage of mononucleated cardiomyocytes from 11.6% to 18% at 5 days post-fistula. These initial differences could not be attributed to cardiomyocyte proliferation, and treatment with a microtubule stabilizing agent prevented them from occurring. The subsequent significant increase in LV weight without corresponding increases in cardiomyocyte dimensions is indicative of hyperplasia. Thus, these findings indicate hyperplasia resulting from cytokinesis of cardiomyocytes is a key mechanism, independent of hypertrophy, that contributes to the significant increase in LV mass in male hearts subjected to chronic volume overload. PMID:20651227
Glue septal ablation: A promising alternative to alcohol septal ablation
Aytemir, Kudret; Oto, Ali
2016-01-01
Hypertrophic cardiomyopathy (HCM) is defined as myocardial hypertrophy in the absence of another cardiac or systemic disease capable of producing the magnitude of present hypertrophy. In about 70% of patients with HCM, there is left ventricular outflow tract (LVOT) obstruction (LVOTO) and this is known as obstructive type of hypertrophic cardiomyopathy (HOCM). Cases refractory to medical treatment have had two options either surgical septal myectomy or alcohol septal ablation (ASA) to alleviate LVOT gradient. ASA may cause some life-threatening complications including conduction disturbances and complete heart block, hemodynamic compromise, ventricular arrhythmias, distant and massive myocardial necrosis. Glue septal ablation (GSA) is a promising technique for the treatment of HOCM. Glue seems to be superior to alcohol due to some intrinsic advantageous properties of glue such as immediate polymerization which prevents the leak into the left anterior descending coronary artery and it is particularly useful in patients with collaterals to the right coronary artery in whom alcohol ablation is contraindicated. In our experience, GSA is effective and also a safe technique without significant complications. GSA decreases LVOT gradient immediately after the procedure and this reduction persists during 12 months of follow-up. It improves New York Heart Association functional capacity and decrease interventricular septal wall thickness. Further studies are needed in order to assess the long-term efficacy and safety of this technique. PMID:27011786
Sulistyowati, Erna; Hsu, Jong-Hau; Cheng, Yuan-Bin; Chang, Fang-Rong; Chen, Ying-Fu; Yeh, Jwu-Lai
2017-10-17
Indonesian herbal medicine Centella asiatica , Justicia gendarussa and Imperata cylindrica decoction (CJID) are known to be efficacious for hypertension. Oxidative stress plays an important role in hypertension-induced left ventricular hypertrophy (H-LVH). This study evaluated whether CJID inhibit cardiac remodeling in spontaneously hypertensive rats (SHRs) through mechanism of oxidative stress-related cardiac-NADPH oxidase (NOXs) pathway: NOX1, NOX2 and NOX4. Forty-weeks-old SHRs and normotensive-WKY rats, were both randomly divided into 2 groups: CJID and control. All rats were treated for 5 weeks. Systolic blood pressure (SBP) and heart rate (HR) were measured. LV morphology, function and performance were assessed by histological staining and echocardiography. Serum and cardiac superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were assessed. Cardiac superoxide and hydrogen peroxide (H 2 O 2 ) productions, protein expressions of SOD2, SOD3, NOX1, NOX2 and NOX4 were also determined. We found that SBP and HR were significantly decreased in SHRs-treated group. Echocardiography showed that CJID significantly improved LV morphometry and function. CJID decreased MDA level, but increased SOD activity. Cardiac superoxide and H 2 O 2 generation were decreased in SHRs-treated group. CJID caused cardiac SODs expressions to be increased but NOXs expressions to be suppressed. In conclusion, CJID prevents H-LVH by reducing reactive oxygen species production via the NOXs-dependent pathway.
Sulistyowati, Erna; Hsu, Jong-Hau; Cheng, Yuan-Bin; Chang, Fang-Rong; Chen, Ying-Fu; Yeh, Jwu-Lai
2017-01-01
Indonesian herbal medicine Centella asiatica, Justicia gendarussa and Imperata cylindrica decoction (CJID) are known to be efficacious for hypertension. Oxidative stress plays an important role in hypertension-induced left ventricular hypertrophy (H-LVH). This study evaluated whether CJID inhibit cardiac remodeling in spontaneously hypertensive rats (SHRs) through mechanism of oxidative stress-related cardiac-NADPH oxidase (NOXs) pathway: NOX1, NOX2 and NOX4. Forty-weeks-old SHRs and normotensive-WKY rats, were both randomly divided into 2 groups: CJID and control. All rats were treated for 5 weeks. Systolic blood pressure (SBP) and heart rate (HR) were measured. LV morphology, function and performance were assessed by histological staining and echocardiography. Serum and cardiac superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were assessed. Cardiac superoxide and hydrogen peroxide (H2O2) productions, protein expressions of SOD2, SOD3, NOX1, NOX2 and NOX4 were also determined. We found that SBP and HR were significantly decreased in SHRs-treated group. Echocardiography showed that CJID significantly improved LV morphometry and function. CJID decreased MDA level, but increased SOD activity. Cardiac superoxide and H2O2 generation were decreased in SHRs-treated group. CJID caused cardiac SODs expressions to be increased but NOXs expressions to be suppressed. In conclusion, CJID prevents H-LVH by reducing reactive oxygen species production via the NOXs-dependent pathway. PMID:29156835
Left Ventricular Hypertrophy and Cognitive Decline in Old Age.
Mahinrad, Simin; Vriend, Annelotte E; Jukema, J Wouter; van Heemst, Diana; Sattar, Naveed; Blauw, Gerard Jan; Macfarlane, Peter W; Clark, Elaine N; de Craen, Anton J M; Sabayan, Behnam
2017-01-01
Patients with advanced heart failure run a greater risk of dementia. Whether early cardiac structural changes also associate with cognitive decline is yet to be determined. We tested whether left ventricular hypertrophy (LVH) derived from electrocardiogram associates with cognitive decline in older subjects at risk of cardiovascular disease. We included 4,233 participants (mean age 75.2 years, 47.8% male) from PROSPER (PROspective Study of Pravastatin in the Elderly at Risk). LVH was assessed from baseline electrocardiograms by measuring the Sokolow-Lyon index. Higher levels of Sokolow-Lyon index indicate higher degrees of LVH. Cognitive domains involving selective attention, processing speed, and immediate and delayed memory were measured at baseline and repeated during a mean follow-up of 3.2 years. At baseline, LVH was not associated with worse cognitive function. During follow-up, participants with higher levels of LVH had a steeper decline in cognitive function including in selective attention (p = 0.009), processing speed (p = 0.010), immediate memory (p < 0.001), and delayed memory (p = 0.002). These associations were independent of cardiovascular risk factors, co-morbidities, and medications. LVH assessed by electrocardiogram associates with steeper decline in cognitive function of older subjects independent of cardiovascular risk factors and co-morbidities. This study provides further evidence on the link between subclinical cardiac structural changes and cognitive decline in older subjects.
[Meningoencephalitis and ventricular arrhythmia caused by yersiniosis].
Pehlke, J R; Geipel, U; von Müller, L; Spiegel, J
2012-09-01
We report on a 19-year-old patient without any immunodeficiency and without a history of significant diseases in whom two seizure attacks as symptoms of meningoencephalitis occurred after he had suffered from abdominal symptoms for a week. Later, we could observe frequent polymorphic ventricular extrasystoles. A massive production of anti-Yersinia IgM, IgG and IgA as a sign of an acute infection could be found, although we were not able to detect the microbe itself with culturing methods. After targetted antibiotic treatment, the patient fully recovered within two weeks and could be discharged from hospital without clinical abnormalities and an almost normalised cell count in the cerebrospinal fluid. Possible ways of infection are mice which the patient kept as pets and his work in the sewer system. The present case reminds us to think of uncommon infectious agents even in young patients without a predisposition but unusual symptoms and/or potentially relevant anamnestic data. © Georg Thieme Verlag KG Stuttgart · New York.
de Andrade, Elisabeth Campos; de Castro Paiva, Kelly Christina; da Silva Guedes, Sarah; Souza, Mariana Lima C; Pereira, Marina Novellino; Miana, Laura Pimenta; de Figueiredo, André Avarese; de Bessa, José; Netto, José Murillo B
2017-08-01
Testosterone is often used in the preoperative period of hypospadias surgery. Previous studies have demonstrated the presence of androgen receptors in cardiac myocytes that can modulate the phenotype. The use of supraphysiological doses of androgens can lead to toxicity on the heart muscle and, in some cases, to left ventricular hypertrophy. This randomized double blind controlled clinical trial aims to evaluate the effect of topical testosterone on left ventricular mass index in boys with hypospadias. Boys with hypospadias aged 6 months to 9 years were included. Children were divided into two groups: G1 - boys who received testosterone propionate 1% ointment twice a day for 30 days, and G2 - boys receiving placebo ointment in the same regimen. All children were submitted to bi-dimensional echocardiographic evaluation to compare the left ventricular mass index, blood pressure, and body mass index before and after treatment (30 and 90 days). Levels of serum testosterone, LH, and FSH were measured. Thirty-five children were analyzed: 17 in G1 and 18 in G2. No differences were found in left ventricular mass index (left ventricular mass indexed by body surface area) prior to treatment. Left ventricular mass index was 59.21 ± 11.91 g/m 2 in G1 and 55.12 ± 8.29 g/m 2 in G2 (p = 0.244) after 30 days of treatment, and 61.13 ± 11.69 g/m 2 in G1 and 62.84 ± 35.99 g/m 2 in G2 (p = 0.852) after 90 days. Serum testosterone levels were 12 (7-80) ng/dL in G1 and 5 (5-7) ng/dL in G2 (p = 0.018) after 30 days of treatment, and 10 (5-11) ng/dL in G1 and 5 (4-5) ng/dL in G2 (p = 0.155), after 90 days (Figure). There was a small increase in systolic blood pressure (SBP) after 30 days (83.82 ± 7.18 mmHg) in the group who receive testosterone (G1) compared with controls (77.5 ± 6.69 mmHg) (p = 0.010). After 90 days, SBP levels returned to basal levels in G1 (82.35 ± 5.62 mmHg) and in G2 (81.38 ± 4.79 mmHg) (p = 0.588). Topical testosterone can be considered safe in the preoperative period of children with hypospadias with no risk of left ventricular hypertrophy. An increase in systolic blood pressure occurs while using testosterone but it is transitory, returning to normal levels after 90 days. Copyright © 2017 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Oxidative stress contributes to methamphetamine-induced left ventricular dysfunction.
Lord, Kevin C; Shenouda, Sylvia K; McIlwain, Elizabeth; Charalampidis, Dimitrios; Lucchesi, Pamela A; Varner, Kurt J
2010-07-01
Our aim was to test the hypothesis that the repeated, binge administration of methamphetamine would produce oxidative stress in the myocardium leading to structural remodeling and impaired left ventricular function. Echocardiography and Millar pressure-volume catheters were used to monitor left ventricular structure and function in rats subjected to four methamphetamine binges (3 mg/kg, iv for 4 days, separated by a 10-day drug-free period). Hearts from treated and control rats were used for histological or proteomic analysis. When compared with saline treatment, four methamphetamine binges produced eccentric left ventricular hypertrophy. The drug also significantly impaired systolic function (decreased fractional shortening, ejection fraction, and adjusted maximal power) and produced significant diastolic dysfunction (increased -dP/dt and tau). Dihydroethedium staining showed that methamphetamine significantly increased (285%) the levels of reactive oxygen species in the left ventricle. Treatment with methamphetamine also resulted in the tyrosine nitration of myofilament (desmin, myosin light chain) and mitochondrial (ATP synthase, NADH dehydrogenase, cytochrome c oxidase, prohibitin) proteins. Treatment with the superoxide dismutase mimetic, tempol in the drinking water prevented methamphetamine-induced left ventricular dilation and systolic dysfunction; however, tempol (2.5 mM) did not prevent the diastolic dysfunction. Tempol significantly reduced, but did not eliminate dihydroethedium staining in the left ventricle, nor did it prevent the tyrosine nitration of mitochondrial and contractile proteins. This study shows that oxidative stress plays a significant role in mediating methamphetamine-induced eccentric left ventricular dilation and systolic dysfunction.
Oxidative stress contributes to methamphetamine-induced left ventricular dysfunction
Lord, Kevin C.; Shenouda, Sylvia K.; McIlwain, Elizabeth; Charalampidis, Dimitrios; Lucchesi, Pamela A.; Varner, Kurt J.
2010-01-01
Aims Our aim was to test the hypothesis that the repeated, binge administration of methamphetamine would produce oxidative stress in the myocardium leading to structural remodeling and impaired left ventricular function. Methods and results Echocardiography and Millar pressure–volume catheters were used to monitor left ventricular structure and function in rats subjected to four methamphetamine binges (3 mg/kg, iv for 4 days, separated by a 10-day drug-free period). Hearts from treated and control rats were used for histological or proteomic analysis. When compared with saline treatment, four methamphetamine binges produced eccentric left ventricular hypertrophy. The drug also significantly impaired systolic function (decreased fractional shortening, ejection fraction, and adjusted maximal power) and produced significant diastolic dysfunction (increased −dP/dt and tau). Dihydroethedium staining showed that methamphetamine significantly increased (285%) the levels of reactive oxygen species in the left ventricle. Treatment with methamphetamine also resulted in the tyrosine nitration of myofilament (desmin, myosin light chain) and mitochondrial (ATP synthase, NADH dehydrogenase, cytochrome c oxidase, prohibitin) proteins. Treatment with the superoxide dismutase mimetic, tempol in the drinking water prevented methamphetamine-induced left ventricular dilation and systolic dysfunction; however, tempol (2.5 mM) did not prevent the diastolic dysfunction. Tempol significantly reduced, but did not eliminate dihydroethedium staining in the left ventricle, nor did it prevent the tyrosine nitration of mitochondrial and contractile proteins. Conclusion This study shows that oxidative stress plays a significant role in mediating methamphetamine-induced eccentric left ventricular dilation and systolic dysfunction. PMID:20139112
Propionyl-L-carnitine limits chronic ventricular dilation after myocardial infarction in rats.
Micheletti, R; Di Paola, E D; Schiavone, A; English, E; Benatti, P; Capasso, J M; Anversa, P; Bianchi, G
1993-04-01
To determine whether propionyl-L-carnitine (PLC) administration ameliorates ventricular remodeling after myocardial infarction, we performed coronary occlusion in rats and examined the long-term effects of the drug 19-24 wk after surgery. In view of the well-established role of angiotensin-converting enzyme (ACE) inhibitors in the reduction of ventricular dilation after infarction, the therapeutic impact of oral PLC (60 mg/kg) was compared with that of enalapril (1 mg/kg). Infarct size measured planimetrically was found to be comparable in untreated, PLC-treated, and enalapril-treated rats, averaging 40-46% of the left ventricular free wall. Heart weight was increased 14, 16, and 11% with no treatment, with PLC, and with enalapril, respectively. The relationship between left ventricular filling pressure and chamber volume demonstrated that PLC and enalapril significantly prevented the expansion in cavitary size after infarction. These protective influences were observed throughout the range of filling pressures measured, from 0 to 30 mmHg. At a uniform reference point of filling pressure of 4 mmHg, untreated infarcted hearts showed an expansion in ventricular volume of 2.17-fold (P < 0.0001). Corresponding increases in this parameter after PLC and enalapril were 36 and 43%, respectively, both not statistically significant. Moreover, PLC was capable of reducing the alterations in myocardial compliance associated with myocardial infarction. In conclusion, PLC reduces the magnitude of decompensated eccentric hypertrophy produced by myocardial infarction in a manner similar to that found with ACE inhibition.
Leite, Nayara de Carvalho; Ferreira, Thiago Rentz; Rickli, Sarah; Borck, Patricia Cristine; Mathias, Paulo Cezar de Freitas; Emilio, Henriette Rosa de Oliveira; Grassiolli, Sabrina
2013-01-01
Obese rats obtained by neonatal monosodium glutamate (MSG) administration present insulin hypersecretion. The metabolic mechanism by which glucose catabolism is coupled to insulin secretion in the pancreatic β-cells from MSG-treated rats is understood. The purpose of this study was to evaluate glucose metabolism in pancreatic islets from MSG-treated rats subjected to swimming training. MSG-treated and control (CON) rats swam for 30 minutes (3 times/week) over a period of 10 weeks. Pancreatic islets were isolated and incubated with glucose in the presence of glycolytic or mitochondrial inhibitors. Swimming training attenuated fat pad accumulation, avoiding changes in the plasma levels of lipids, glucose and insulin in MSG-treated rats. Adipocyte and islet hypertrophy observed in MSG-treated rats were attenuated by exercise. Pancreatic islets from MSG-treated obese rats also showed insulin hypersecretion, greater glucose transporter 2 (GLUT2) expression, increased glycolytic flux and reduced mitochondrial complex III activity. Swimming training attenuated islet hypertrophy and normalised GLUT2 expression, contributing to a reduction in the glucose responsiveness of pancreatic islets from MSG-treated rats without altering glycolytic flux. However, physical training increased the activity of mitochondrial complex III in pancreatic islets from MSG-treated rats without a subsequent increase in glucose-induced insulin secretion. Copyright © 2013 S. Karger AG, Basel.
The Metabolome in Finnish Carriers of the MYBPC3-Q1061X Mutation for Hypertrophic Cardiomyopathy.
Jørgenrud, Benedicte; Jalanko, Mikko; Heliö, Tiina; Jääskeläinen, Pertti; Laine, Mika; Hilvo, Mika; Nieminen, Markku S; Laakso, Markku; Hyötyläinen, Tuulia; Orešič, Matej; Kuusisto, Johanna
2015-01-01
Mutations in the cardiac myosin-binding protein C gene (MYBPC3) are the most common genetic cause of hypertrophic cardiomyopathy (HCM) worldwide. The molecular mechanisms leading to HCM are poorly understood. We investigated the metabolic profiles of mutation carriers with the HCM-causing MYBPC3-Q1061X mutation with and without left ventricular hypertrophy (LVH) and non-affected relatives, and the association of the metabolome to the echocardiographic parameters. 34 hypertrophic subjects carrying the MYBPC3-Q1061X mutation, 19 non-hypertrophic mutation carriers and 20 relatives with neither mutation nor hypertrophy were examined using comprehensive echocardiography. Plasma was analyzed for molecular lipids and polar metabolites using two metabolomics platforms. Concentrations of branched chain amino acids, triglycerides and ether phospholipids were increased in mutation carriers with hypertrophy as compared to controls and non-hypertrophic mutation carriers, and correlated with echocardiographic LVH and signs of diastolic and systolic dysfunction in subjects with the MYBPC3-Q1061X mutation. Our study implicates the potential role of branched chain amino acids, triglycerides and ether phospholipids in HCM, as well as suggests an association of these metabolites with remodeling and dysfunction of the left ventricle.
Huang, Bao-Tao; Peng, Yong; Liu, Wei; Zhang, Chen; Huang, Fang-Yang; Wang, Peng-Ju; Zuo, Zhi-Liang; Liao, Yan-Biao; Chai, Hua; Li, Qiao; Zhao, Zhen-Gang; Luo, Xiao-Lin; Ren, Xin; Huang, Kai-Sen; Meng, Qing-Tao; Chen, Chi; Huang, De-Jia; Chen, Mao
2014-10-01
A new 4-tired classification of left ventricular hypertrophy (LVH) based on LV concentricity and dilation has been proposed; however, the association between the new categorization of LV geometry and outcomes in patients with coronary artery disease (CAD) is still unknown. All the 2297 patients with CAD included underwent echocardiographic examination prior to discharge. Left ventricular mass (LVM) was calculated, and left ventricular end-diastolic volume (EDV) was indexed by body surface area (BSA). Study cohort was divided into five groups according to LV geometry: (i) eccentric nondilated LVH (normal LVM/EDV((2/3)) and EDV/BSA) (n = 129); (ii) eccentric dilated LVH (normal LVM/EDV((2/3)) with increased EDV/BSA) (n = 222); (iii) concentric nondilated LVH (increased LVM/EDV((2/3)) with normal EDV/BSA) (n = 441); (iv) concentric dilated LVH (increased LVM/EDV((2/3)) and EDV/BSA) (n = 118); and (v) normal LV mass (n = 1387). Dilated LVH was associated with a higher event rates of all-cause death (eccentric 13·1% vs. 3·1%; concentric 13·6% vs. 8·4%) and composite events (eccentric: 17·6% vs. 5·4%; concentric: 18·6% vs. 12·7%) compared with nondilated LVH. While eccentric nondilated LVH had comparable risk for adverse outcomes compared with normal LV mass (all-cause death: relative risk (RR) 0·68, 95% confidential interval (CI) 0·25-1·85; composite events: RR 0·75, 95% CI 0·36-1·58). Cox regression analyses showed that eccentric dilated LVH had the highest propensity to all-cause death (adjusted hazard ratio [aHR] 2·752 [95% CI 1·749-4·328], P < 0·001) and composite events (aHR 2·462 [95% CI 1·688-3·592], P < 0·001). In patients with CAD, dilated LVH and nondilated LVH provide distinct prognostic information. Eccentric nondilated LVH does not predict adverse outcomes. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.
Influence of Physical Activity on Hypertension and Cardiac Structure and Function
Hegde, Sheila M.; Solomon, Scott D.
2015-01-01
The global burden of hypertension is rising and accounts for substantial morbidity and mortality. Lifestyle factors such as diet and physical inactivity contribute to this burden, further highlighting the need for prevention efforts to curb this public health epidemic. Regular physical activity is associated with lower blood pressure, reduced cardiovascular risk, and cardiac remodeling. While exercise and hypertension can both be associated with the development of left ventricular hypertrophy (LVH), the cardiac remodeling from hypertension is pathologic with an associated increase in myocyte hypertrophy, fibrosis, and risk of heart failure and mortality, whereas LVH in athletes is generally non-pathologic and lacks the fibrosis seen in hypertension. In hypertensive patients, physical activity has been associated with paradoxical regression or prevention of LVH, suggesting a mechanism by which exercise can benefit hypertensive patients. Further studies are needed to better understand the mechanisms underlying the benefits of physical activity in the hypertensive heart. PMID:26277725