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Sample records for isolated ventricular noncompaction

  1. [Isolated left ventricular noncompaction causing refractory heart failure].

    PubMed

    Meneguz-Moreno, Rafael Alexandre; Rodrigues da Costa Teixeira, Felipe; Rossi Neto, João Manoel; Finger, Marco Aurélio; Casadei, Carolina; Castillo, Maria Teresa; Sanchez de Almeida, Antonio Flávio

    2016-03-01

    Left ventricular noncompaction is a rare congenital anomaly characterized by excessive left ventricular trabeculation, deep intertrabecular recesses and a thin compacted layer due to the arrest of compaction of myocardial fibers during embryonic development. We report the case of a young patient with isolated left ventricular noncompaction, leading to refractory heart failure that required extracorporeal membrane oxygenation followed by emergency heart transplantation. PMID:26928017

  2. Lown-Ganong-Levine syndrome in a 3-month-old infant with isolated left ventricular noncompaction.

    PubMed

    Shabanian, Reza; Kiani, Abdolrazagh; Rad, Elaheh Malakan; Eslamiyeh, Hosein

    2010-02-01

    This report describes a 3-month-old boy with isolated left ventricular noncompaction admitted to a medical facility due to heart failure and dysrhythmia. His electrocardiogram showed a short PR interval and a normal QRS complex after abortion of supraventricular tachycardia in favor of Lown-Ganong-Levine syndrome or enhanced atrioventricular nodal conduction.

  3. A rare case of heterotaxy and left ventricular non-compaction in an adult.

    PubMed

    Chacko, A; Scholtz, L; Vedajallam, S; van Wyk, C

    2016-01-01

    Heterotaxy syndrome with left ventricular non-compaction is a rare co-existence of abnormalities with unknown cause. It can be isolated with no other associations, or associated with congenital heart diseases, or it can occur with multiple other congenital abnormalities. We describe the third reported case of heterotaxy syndrome with left ventricular non-compaction presenting in an adult. PMID:26323941

  4. Left ventricular noncompaction: A rare indication for pediatric heart transplantation.

    PubMed

    Magalhães, Mariana; Costa, Patrícia; Vaz, Maria Teresa; Pinheiro Torres, José; Areias, José Carlos

    2016-01-01

    Isolated left ventricular noncompaction is a rare congenital cardiomyopathy, characterized morphologically by a dilated left ventricle, prominent trabeculations and deep intertrabecular recesses in the ventricular myocardium, with no other structural heart disease. It is thought to be secondary to an arrest of normal myocardial compaction during fetal life. Clinically, the disease presents with heart failure, embolic events, arrhythmias or sudden death. Current diagnostic criteria are based on clinical and imaging data and two-dimensional and color Doppler echocardiography is the first-line exam. There is no specific therapy and treatment is aimed at associated comorbidities. Cases refractory to medical therapy may require heart transplantation. The authors describe a case of severe and refractory heart failure, which was the initial presentation of isolated left ventricular noncompaction in a previously healthy male child, who underwent successful heart transplantation.

  5. Left Ventricular Noncompaction: A Distinct Genetic Cardiomyopathy?

    PubMed

    Arbustini, Eloisa; Favalli, Valentina; Narula, Nupoor; Serio, Alessandra; Grasso, Maurizia

    2016-08-30

    Left ventricular noncompaction (LVNC) describes a ventricular wall anatomy characterized by prominent left ventricular (LV) trabeculae, a thin compacted layer, and deep intertrabecular recesses. Individual variability is extreme, and trabeculae represent a sort of individual "cardioprinting." By itself, the diagnosis of LVNC does not coincide with that of a "cardiomyopathy" because it can be observed in healthy subjects with normal LV size and function, and it can be acquired and is reversible. Rarely, LVNC is intrinsically part of a cardiomyopathy; the paradigmatic examples are infantile tafazzinopathies. When associated with LV dilation and dysfunction, hypertrophy, or congenital heart disease, the genetic cause may overlap. The prevalence of LVNC in healthy athletes, its possible reversibility, and increasing diagnosis in healthy subjects suggests cautious use of the term LVNC cardiomyopathy, which describes the morphology but not the functional profile of the cardiomyopathy. PMID:27561770

  6. Noncompaction of the ventricular myocardium associated with mitral regurgitation and preserved ventricular systolic function.

    PubMed

    Ali, Sulafa Khalid M; Omran, Ahmed S; Najm, Hani; Godman, Michael J

    2004-01-01

    Noncompaction of the ventricular myocardium is an embryonic cardiomyopathy that is increasingly being recognized. Mitral regurgitation, when present, is usually a result of the associated left ventricular systolic dysfunction. We report 4 patients with noncompaction of the ventricular myocardium in whom ventricular systolic function was preserved. Mitral regurgitation was associated with changes in the mitral valve leaflets and an abnormal coaptation pattern. This association of noncompaction of the ventricular myocardium with mitral regurgitation has not, to our knowledge, been reported.

  7. Adherence to thresholds: overdiagnosis of left ventricular noncompaction cardiomyopathy.

    PubMed

    Kini, Vinay; Ferrari, Victor A; Han, Yuchi; Jha, Saurabh

    2015-08-01

    Thresholds derived from quantification in imaging are increasingly used to define disease. This derivation is not an exact science. When one uses a threshold to define a disease, one does not clearly demarcate disease from normality because the threshold includes overlapping spectra of mild disease and normality. Thus, use of the threshold will mislabel normal individuals with disease. In this perspective, we will describe how the threshold has been derived for left ventricular noncompaction cardiomyopathy, the statistical biases in the design of studies used to derive the threshold, and the dangers of overdiagnosis when the threshold is used to rule out left ventricular noncompaction cardiomyopathy.

  8. Left Ventricular Non-compaction in Holt-Oram Syndrome.

    PubMed

    Kapadia, Renuka; Choudhary, Preeti; Collins, Nicholas; Celermajer, David; Puranik, Rajesh

    2016-06-01

    Holt-Oram Syndrome is an autosomal dominant condition with complete penetrance and which involves upper limb skeletal and cardiac abnormalities. The latter can be structural defects or involve the conduction system. This report details the occurrence of left ventricular non-compaction in multiple family members with Holt-Oram Syndrome. It is recommended that patients with the Holt-Oram Syndrome be considered for comprehensive cardiac evaluation to exclude non-compaction cardiomyopathy as this may have significant prognostic implications. PMID:26874791

  9. Postoperative normalization of left ventricular noncompaction and new echocardiographic signs in aorta to left ventricular tunnel.

    PubMed

    Malakan Rad, Elaheh; Zeinaloo, Ali Akbar

    2013-04-01

    We report postoperative normalization of left ventricular noncompaction in a neonate undergoing successful neonatal surgery for type II aorta to left ventricular tunnel (ALVT) associated with a large patent ductus arteriosus, floppy and extremely redundant anterior mitral leaflet, right coronary artery arising directly from the tunnel, and severe left ventricular noncompaction. We also described 2 novel echocardiographic findings in ALVT including "triple wavy line sign" on M-mode echocardiography which disappeared 1 month after operation and "abnormally increased left ventricular posterior wall motion" on M-mode of standard parasternal long-axis view on color tissue Doppler imaging (TDI) that also normalized postoperatively. We showed that proper definition of endocardial border is extremely important in strain and strain rate imaging in the context of left ventricular noncompaction. Preoperative longitudinal strain and strain rate were significantly decreased in comparison to radial strain and strain rate. Circumferential strain and strain rate were normal. PMID:23346986

  10. Ebstein's Anomaly, Left Ventricular Noncompaction, and Sudden Cardiac Death

    PubMed Central

    McGee, Michael; Warner, Luke; Collins, Nicholas

    2015-01-01

    Ebstein's anomaly is a congenital disorder characterized by apical displacement of the septal leaflet of the tricuspid valve. Ebstein's anomaly may be seen in association with other cardiac conditions, including patent foramen ovale, atrial septal defect, and left ventricular noncompaction (LVNC). LVNC is characterized by increased trabeculation within the left ventricular apex. Echocardiography is often used to diagnose LVNC; however, magnetic resonance (MR) imaging offers superior characterization of the myocardium. We report a case of sudden cardiac death in a patient with Ebstein's anomaly with unrecognized LVNC noted on post mortem examination with screening documenting the presence of LVNC in one of the patient's twin sons. PMID:26240764

  11. Noncompaction of the Ventricular Myocardium and Polycystic Kidney Disease: A Case Report.

    PubMed

    Fukino, Keiko; Ishiwata, Junpei; Shinohara, Hiroki; Oshima, Tsukasa; Kozaki, Tsunashi; Ikutomi, Masayasu; Amaki, Toshihiro; Nakamura, Fumitaka

    2016-06-01

    Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common hereditary disorders, characterized by the formation of multiple cysts in the kidneys and other organs, as well as noncystic manifestations such as cerebral aneurysm. The most common cardiovascular disorders associated with ADPKD include valvular abnormalities and aortic aneurysm. An association between ADPKD and impaired left ventricular function has occasionally been reported. We describe a 74-year-old woman with ADPKD and exertional dyspnea. Impaired left ventricular function resulting from noncompaction of the ventricular myocardium (NVM) and secondary left ventricular aneurysm were diagnosed. Cardiac sarcoidosis and ischemic heart disease were ruled out. Myocardial ischemia resulting from NVM was the presumptive cause of the ventricular aneurysm. To our knowledge, this is the first report of concurrent isolated NVM and left ventricular aneurysm in a patient with ADPKD. ADPKD and various cardiomyopathies, including NVM, are all reported to involve mutations of sarcomere genes, suggesting a possible link between the conditions. PMID:26873255

  12. Right ventricular noncompaction in a neonate with complex congenital heart disease.

    PubMed

    Alehan, Dursun; Dogan, Omer Faruk

    2005-08-01

    Ventricular noncompaction is a rare unclassified cardiomyopathy occurring because of arrest of the normal intrauterine compaction of the loose luminal component of the ventricular myocardium. There is limited data regarding its diagnosis and outcome in children. It is recognised, however, that right ventricular involvement is extremely rare. We report a case in which only the right ventricular myocardium was noncompacted, a situation which led to heart failure soon after birth.

  13. A rare form of cardiomyopathy: left ventricular non-compaction cardiomyopathy

    PubMed Central

    Goud, Aditya; Padmanabhan, Sriram

    2016-01-01

    Left ventricular non-compaction is a recently recognized, rare form of cardiomyopathy. It is based on the arrest of endomyocardial morphogenesis during embryogenesis. It was first described in 1984 by Engberding who described it as isolated ‘sinusoids’ within the LV. Right now its prevalence is estimated at 0.014 to 1.3 and 3–4% in heart failure patients. Its clinical manifestations are highly variable, ranging from no symptoms to disabling congestive heart failure, arrhythmias, and systemic thromboemboli. Doppler Echocardiogram is considered the diagnostic procedure of choice and treatment is symptomatic management of its symptoms and complications. PMID:26908378

  14. Incessant slow bundle branch reentrant ventricular tachycardia in a young patient with left ventricular noncompaction.

    PubMed

    Barra, Sérgio; Moreno, Nuno; Providência, Rui; Gonçalves, Helena; Primo, João José

    2013-06-01

    A 15-year-old girl was admitted to the cardiology outpatient clinic due to mild palpitations and documented incessant slow ventricular tachycardia (VT) with left bundle branch block (LBBB) pattern. The baseline electrocardiogram revealed first-degree atrioventricular block and intraventricular conduction defect. Transthoracic echocardiography showed prominent trabeculae and intertrabecular recesses suggesting left ventricular noncompaction (LVNC), which was confirmed by cardiac magnetic resonance imaging. During electrophysiological study, a sustained bundle branch reentrant VT with LBBB pattern and cycle length of 480 ms, similar to the clinical tachycardia, was easily and reproducibly inducible. As there was considerable risk of need for chronic ventricular pacing following right bundle ablation, no ablation was attempted and a cardioverter-defibrillator was implanted. To the best of our knowledge, no case reports of BBR-VT as the first manifestation of LVNC have been published. Furthermore, this is an extremely rare presentation of BBR-VT, which is usually a highly malignant arrhythmia.

  15. Congenital left ventricular aneurysm coexisting with left ventricular non-compaction in a newborn.

    PubMed

    Ootani, Katsuki; Shimada, Jun; Kitagawa, Yosuke; Konno, Yuki; Miura, Fumitake; Takahashi, Toru; Ito, Etsuro; Ichinose, Kouta; Yonesaka, Susumu

    2014-10-01

    Described herein is the case of a rare combination of congenital left ventricular (LV) aneurysm and left ventricular non-compaction (LVNC) in a newborn. The patient developed refractory heart failure soon after birth and died at 5 months of age. The etiology of both congenital LV aneurysm and LVNC seems to be maldevelopment of the ventricular myocardium during early fetal life. Treatment should be individually tailored depending on clinical severity, and treatment options are limited. Given that this combination of congenital LV aneurysm and LVNC is significantly associated with poor prognosis, it appears that patients with congenital LV aneurysm and LVNC are candidates for early, aggressive intervention, including surgical aneurysmectomy and evaluation for transplantation. It is important to be aware of this combination of congenital LV aneurysm and LVNC, and to make earlier decisions on therapeutic strategy.

  16. Left Ventricular Non-Compaction –Challenges and Controversies

    PubMed Central

    FLORIA, Mariana; TINICA, Grigore; GRECU, Mihaela

    2014-01-01

    Cardiomyopathies classification is based on morphological and functional phenotypes and subcategories of familial/genetic and non-familial/non-genetic disease. The non-compaction cardiomyopathy is a rare disorder which is considered to be an unclassified cardiomyopathy according to the ESC Working Group on Myocardial and Pericardial Diseases and the World Health Organization or a primary genetically-determined cardiomyopathy according to the American Heart Association. The diagnosis of non-compaction is challenging and its nosology is debated since this morphological trait can be shared by different cardiomyopathies and non-cardiomyopathy conditions. Myocardial structure has a spectrum from normal variants to the pathological phenotype of non-compaction cardiomyopathy, which reflects the embryonic structure of the human heart due to an arrest in the compaction process during the first trimester. However, when a definite diagnosis of non-compaction is made, the diagnostic process should orient towards a genetic disease with a relatively high probability of sarcomere mutations. Non-compaction cardiomyopathy is a diagnostically challenging entity. Nowadays there are some controversies associated with this cardiomyopathy, that it worth to be discussed. PMID:25705294

  17. Left ventricular non-compaction -challenges and controversies.

    PubMed

    Floria, Mariana; Tinica, Grigore; Grecu, Mihaela

    2014-09-01

    Cardiomyopathies classification is based on morphological and functional phenotypes and subcategories of familial/genetic and non-familial/non-genetic disease. The non-compaction cardiomyopathy is a rare disorder which is considered to be an unclassified cardiomyopathy according to the ESC Working Group on Myocardial and Pericardial Diseases and the World Health Organization or a primary genetically-determined cardiomyopathy according to the American Heart Association. The diagnosis of non-compaction is challenging and its nosology is debated since this morphological trait can be shared by different cardiomyopathies and non-cardiomyopathy conditions. Myocardial structure has a spectrum from normal variants to the pathological phenotype of non-compaction cardiomyopathy, which reflects the embryonic structure of the human heart due to an arrest in the compaction process during the first trimester. However, when a definite diagnosis of non-compaction is made, the diagnostic process should orient towards a genetic disease with a relatively high probability of sarcomere mutations. Non-compaction cardiomyopathy is a diagnostically challenging entity. Nowadays there are some controversies associated with this cardiomyopathy, that it worth to be discussed.

  18. Left Ventricular Non-Compaction in Athletes: To Play or Not to Play.

    PubMed

    Coris, Eric Emmanuel; Moran, Byron Keith; De Cuba, Raymond; Farrar, Ted; Curtis, Anne B

    2016-09-01

    Isolated left ventricular non-compaction (LVNC) has usually been viewed as a rare cardiomyopathy in athletes. However, with advances in diagnostic imaging techniques and increased use of pre-participation screening electrocardiograms (ECGs), apparent LVNC is being recognized in an increasing number of athletes. Given the lack of a true gold standard for diagnosis, significant debate continues regarding optimal diagnostic criteria. There are increasing data to support the possibility of over-diagnosing this cardiomyopathy in an athletic population due to the physiologic adaptation to the extreme preload and afterload characteristic of intense athletic participation. This appears to be particularly true in African-American or African-Caribbean athletes. The most common presenting symptom in the athlete with true LVNC is exertional syncope. Evaluation of the at-risk athlete will typically include a complete history, with attention to cardiac symptoms, family history of premature cardiovascular disease or sudden cardiac death (SCD), physical examination, 12-lead ECG, two-dimensional echocardiography, and, in some cases, cardiac magnetic resonance imaging with gadolinium contrast. In addition, stress echocardiography, 24- to 48-h Holter monitoring, or 30-day event monitoring for arrhythmias may be necessary to fully evaluate the athlete's risk. Adverse outcomes with LVNC include ventricular dysfunction, arrhythmias, syncope, SCD, and thromboembolism. Asymptomatic athletes with hypertrabeculation of the left ventricle but normal ventricular function likely do not require restrictions on activity. Symptomatic individuals who meet criteria for LVNC, especially those with abnormal ventricular function and exercise-induced symptoms or arrhythmias, should be prohibited from participating in vigorous sports activities. PMID:27002622

  19. Left Ventricular Noncompaction Combined With Epinephrine-Secreted Pheochromocytoma Inducing Heart Failure.

    PubMed

    Han, Ling; Luo, Jing-Gang; Chen, Xin; Hu, Wen-Ze; Chen, Li-Wei; Xin, Xiao-Ming; Yang, Ming; Duan, Jun; Zou, Feng-Jun; Teng, Xu; Qi, Yong-Fen

    2016-01-01

    Pheochromocytomas and left ventricular noncompaction (LVNC) are both rare diseases. In this patient, the long duration of the catecholamine-secreted pheochromocytoma caused myocardial ischemia, pressure overload, and hypertrophy, resulting in the onset of heart failure (HF). The LVNC might be associated with the acute attack of HF induced by the pheochromocytoma. This is the first case reporting LVNC in combination with HF secondary to pheochromocytoma.

  20. Pregnancy and treatment outcome in a patient with left ventricular non-compaction.

    PubMed

    Sawant, Rahul D; Freeman, Leisa J; Stanley, Katherine P S; McKelvey, Alistair

    2013-05-01

    Left ventricular non-compaction (LVNC) is a rare form of cardiomyopathy. This case reviews a woman with familial LVNC (EF 45%, NYHA class I, evidence of non-sustained ventricular tachycardia pre-pregnancy) who had significant decompensation with heart failure in the third trimester that required early delivery. Deterioration in symptoms and LV function 7 days after delivery required further hospitalization and aggressive treatment. Suppression of lactation with bromocriptine, together with standard heart failure management, has allowed recovery and return to full activities and work. Acknowledged adverse risk factors in LVNC are considered, and pre-pregnancy risk assessment is reviewed. There is no specific treatment for LVNC in pregnancy besides the usual management of dilated cardiomyopathy. This is the ninth case report of LVNC in pregnancy reported in the literature.

  1. Left ventricular noncompaction in patients with β-thalassemia: uncovering a previously unrecognized abnormality.

    PubMed

    Piga, Antonio; Longo, Filomena; Musallam, Khaled M; Veltri, Andrea; Ferroni, Francesca; Chiribiri, Amedeo; Bonamini, Rodolfo

    2012-12-01

    Left ventricular noncompaction (LVNC) is a rare cardiomyopathy with potentially serious outcomes. It results in multiple and excessive trabeculations, deep intertrabecular recesses, and a thickened ventricular myocardium with two distinct layers, compacted and noncompacted. The condition is most commonly congenital; however, acquired forms have also been described. A recent report of LVNC detected in a β-thalassemia twin suggested an association with cardiac siderosis. In a cross-sectional study of 135 transfusion-dependent patients with β-thalassemia (130 major and 5 intermedia, mean age 29.6 ± 7.7 years, 49.6% males) presenting for cardiac iron assessment by magnetic resonance imaging (MRI), we evaluated the prevalence and risk factors for LVNC. None of the patients had neuromuscular or congenital heart disease. Eighteen patients (13.3%; 95% confidence interval [CI] = 8.6-20.1) fulfilled the preassigned strict criteria for LVNC on cardiac MRI. There were no statistically significant differences between patients with and without LVNC with respect to demographics; hemoglobin levels; splenectomy status; systemic, hepatic, and cardiac iron overload indices; hepatic disease and infection studies; or iron chelator type. Patients with LVNC were more likely to have heart failure (adjusted odds ratio = 1.77; 95% CI = 0.29-10.89); although with high uncertainty. Patients with β-thalassemia have a higher prevalence of LVNC than normal individuals. As this finding could not be explained by conventional risk factors in this patient population, further investigation of the underlying mechanisms of LVNC is warranted. This remains crucial for an entity with adverse cardiac outcomes, especially in patients with β-thalassemia where cardiac disease remains a primary cause of mortality.

  2. Loss of Function Mutations in NNT Are Associated with Left Ventricular Noncompaction

    PubMed Central

    Bainbridge, Matthew N.; Davis, Erica E.; Choi, Wen-Yee; Dickson, Amy; Martinez, Hugo R.; Wang, Min; Dinh, Huyen; Muzny, Donna; Pignatelli, Ricardo; Katsanis, Nicholas; Boerwinkle, Eric; Gibbs, Richard; Jefferies, John L.

    2015-01-01

    Background Left ventricular noncompaction (LVNC) is an autosomal dominant, genetically heterogeneous cardiomyopathy with variable severity, which may co-occur with cardiac hypertrophy. Methods and Results Here, we generated whole exome sequence (WES) data from multiple members from five families with LVNC. In four out of five families, the candidate causative mutation segregates with disease in known LVNC genes MYH7 and TPM1. Subsequent sequencing of MYH7 in a larger LVNC cohort identified seven novel likely disease causing variants. In the fifth family, we identified a frameshift mutation in NNT, a nuclear encoded mitochondrial protein, not implicated previously in human cardiomyopathies. Resequencing of NNT in additional LVNC families identified a second likely pathogenic missense allele. Suppression of nnt in zebrafish caused early ventricular malformation and contractility defects, likely driven by altered cardiomyocyte proliferation. In vivo complementation studies showed that mutant human NNT failed to rescue nnt morpholino-induced heart dysfunction, indicating a probable haploinsufficiency mechanism. Conclusions Together, our data expand the genetic spectrum of LVNC and demonstrate how the intersection of WES with in vivo functional studies can accelerate the identification of genes that drive human genetic disorders. PMID:26025024

  3. A Rare Association of Non-Compaction of the Ventricular Myocardium, and Non-Immune Hydrops Fetalis.

    PubMed

    Nandyal, Raja; Moorthy, Ganga

    2016-01-01

    Hydrops fetalis is a rare manifestation of severe congestive heart failure in a fetus, resulting in pathological fluid accumulation in fetal soft tissues and/or serous cavities. Non-compaction of the ventricular myocardium, frequently referred to as the left ventricular non-compaction (LVNC), is a very rare congenital cardiomyopathy. For LVNC, echocardiography is the diagnostic modality of choice. Various diagnostic criteria exist based on either echocardiography or MRI. Currently, nonimmune hydrops fetalis (NIHF) comprise almost 90% of all hydrops fetalis cases. Among cardiovascular conditions that contribute to NIHF (20%), structural malformations (especially hypoplastic left heart, endocardial cushion defect) and arrhythmias are the most frequent etiological factors. We describe an extremely preterm neonate who presented with features of non-Immune hydrops fetalis (NIHF) associated with LVNC and profound refractory systemic hypotension. PMID:27328555

  4. Left Ventricular Noncompaction Diagnosis and Management Relevant to Pre-participation Screening of Athletes.

    PubMed

    Caselli, Stefano; Attenhofer Jost, Christine H; Jenni, Rolf; Pelliccia, Antonio

    2015-09-01

    Left ventricular noncompaction (LVNC) has been extensively studied over the last years, and an increasing number of cases have been reported worldwide, with a large proportion comprising young and asymptomatic subjects, including athletes. The current epidemic of LVNC is likely the consequence of several causes, that is, the increased awareness of the disease and the refined cardiovascular imaging techniques. The current diagnostic methods, based uniquely on definition of morphologic findings, do not always resolve the overlap of a physiological myocardial architecture comprising a prominent trabecular pattern from a mild phenotypic expression of the real disease. Appropriate criteria for identification and management of LVNC in athletes have, therefore, become a novel challenge for cardiologists and sport physicians, who are required to solve the question of diagnosis and appropriate management in the setting of pre-participation cardiovascular screening. Indeed, although it is important to timely identify a true myocardial disease, to reduce the burden of adverse cardiac event in a young athlete, in contrast, a misdiagnosis of LVNC may lead to unwarranted restriction of the athlete lifestyle, with detrimental psychological, social, and economic consequences. This review report has been planned, therefore, to help physicians in diagnosing and managing athletes presenting with a morphologic pattern suggestive of LVNC with specific focus on criteria for advising sport participation.

  5. Isolated noncompaction of the myocardium: multiplane transesophageal echocardiography diagnosis in an adult.

    PubMed

    Maltagliati, A; Pepi, M

    2000-11-01

    We describe a case of isolated noncompaction of the myocardium in a 66-year-old patient. Peculiar anatomic features of this disease were clearly suspected on transthoracic echocardiography and precisely recognized through transesophageal echocardiography. The role of transthoracic and transesophageal echocardiography in the detection of this rare disease is described in this report.

  6. Left ventricular non-compaction revealed by aortic regurgitation due to Kawasaki disease in a boy with LDB3 mutation.

    PubMed

    Hachiya, Akira; Motoki, Noriko; Akazawa, Yohei; Matsuzaki, Satoshi; Hirono, Keiichi; Hata, Yukiko; Nishida, Naoki; Ichida, Fukiko; Koike, Kenichi

    2016-08-01

    Kawasaki disease (KD) is an acute febrile illness of childhood characterized by systemic vasculitis, especially coronary arteritis. Aortic valve regurgitation (AVR) is a relatively common complication. There have been no reports to date of heart failure and left ventricular non-compaction (LVNC) after acute KD, although the precise etiology of this condition remains unclear. A 6-month-old boy with KD was admitted to hospital. Despite high-dose i.v. gammaglobulin for dilation of the coronary artery, moderate AVR appeared, and thereafter he developed heart failure. A rough, dense LV myocardium indicated LVNC. On genetic testing a heterogenous 163G > A substitution changing a valine to isoleucine in LIM domain binding protein 3 (LDB3) was identified. Additional cardiac stress, such as that caused by AVR and/or KD might have triggered cardiac failure in the form of LVNC due to LDB3 mutation.

  7. The variable clinical presentation of, and outcome for, noncompaction of the ventricular myocardium in infants and children, an under-diagnosed cardiomyopathy.

    PubMed

    Ali, Sulafa K M; Godman, Michael J

    2004-08-01

    Noncompaction of the ventricular myocardium is increasingly recognized as an important cause of cardiomyopathy. Its echocardiographic definition, however, is not yet clearly refined, and differentiation from other conditions with hypertrabeculation can be difficult. We report a prospective short-term follow-up of 15 children with noncompaction, excluding those with associated complex congenital cardiac disease. The clinical presentation and outcome were variable, with 2 patients being asymptomatic. For 5 patients, presentation was with cardiac failure due to depressed myocardial function. The function deteriorated in two, remained the same in two, and improved in the other patient. Cardiac failure due to mitral regurgitation was the mode of presentation in 2 patients with preserved myocardial function, one of whom needed replacement of the mitral valve. In 6 patients (40%), symptoms of cardiac failure were due to noncomplex congenital cardiac disease. All of them had ventricular septal defects. In addition, two had cleft mitral valves, and one had a large persistently patent arterial duct. The diagnosis of noncompaction was initially missed on more than one echocardiographic study in one-third of our patients. We conclude that noncompaction is under-diagnosed, and is not as rare as is thought. In children, it is often associated with other cardiac lesions that can cause cardiac failure in the presence of preserved myocardial function.

  8. PLEKHM2 mutation leads to abnormal localization of lysosomes, impaired autophagy flux and associates with recessive dilated cardiomyopathy and left ventricular noncompaction.

    PubMed

    Muhammad, Emad; Levitas, Aviva; Singh, Sonia R; Braiman, Alex; Ofir, Rivka; Etzion, Sharon; Sheffield, Val C; Etzion, Yoram; Carrier, Lucie; Parvari, Ruti

    2015-12-20

    Gene mutations, mostly segregating with a dominant mode of inheritance, are important causes of dilated cardiomyopathy (DCM), a disease characterized by enlarged ventricular dimensions, impaired cardiac function, heart failure and high risk of death. Another myocardial abnormality often linked to gene mutations is left ventricular noncompaction (LVNC) characterized by a typical diffuse spongy appearance of the left ventricle. Here, we describe a large Bedouin family presenting with a severe recessive DCM and LVNC. Homozygosity mapping and exome sequencing identified a single gene variant that segregated as expected and was neither reported in databases nor in Bedouin population controls. The PLEKHM2 cDNA2156_2157delAG variant causes the frameshift p.Lys645AlafsTer12 and/or the skipping of exon 11 that results in deletion of 30 highly conserved amino acids. PLEKHM2 is known to interact with several Rabs and with kinesin-1, affecting endosomal trafficking. Accordingly, patients' primary fibroblasts exhibited abnormal subcellular distribution of endosomes marked by Rab5, Rab7 and Rab9, as well as the Golgi apparatus. In addition, lysosomes appeared to be concentrated in the perinuclear region, and autophagy flux was impaired. Transfection of wild-type PLEKHM2 cDNA into patient's fibroblasts corrected the subcellular distribution of the lysosomes, supporting the causal effect of PLEKHM2 mutation. PLEKHM2 joins LAMP-2 and BAG3 as a disease gene altering autophagy resulting in an isolated cardiac phenotype. The association of PLEKHM2 mutation with DCM and LVNC supports the importance of autophagy for normal cardiac function. PMID:26464484

  9. Orthotopic heart transplantation in two infants with histiocytoid cardiomyopathy and left ventricular non-compaction.

    PubMed

    Siehr, Stephanie L; Bernstein, Daniel; Yeh, Justin; Berry, Gerald J; Rosenthal, David N; Hollander, Seth A

    2013-11-01

    HC is a rare cause of congestive heart failure that typically presents with malignant ventricular arrhythmias in infants, often requiring urgent intervention. Successful heart transplantation in a patient with HC has only been reported once (J Heart Lung Transplant 2004: 23: 902). The combination of HC with concurrent LVNC has only been described three times (Int J Legal Med 2009: 123: 47; Hum Pathol 2005: 36: 403; Pediatr Dev Pathol 2012: 15: 397). We report two rare cases of HC with LVNC in two infants presenting with cardiogenic shock, one requiring ECMO support who was successfully bridged to orthotopic heart transplantation with a Berlin Heart LVAD.

  10. Monoamniotic monochorionic twins discordant for noncompaction cardiomyopathy.

    PubMed

    Ng, Dianna; Bouhlal, Yosr; Ursell, Philip C; Shieh, Joseph T C

    2013-06-01

    Occasionally "identical twins" are phenotypically different, raising the question of zygosity and the issue of genetic versus environmental influences during development. We recently noted monochorionic-monoamniotic twins, one of which had an isolated cardiac abnormality, noncompaction cardiomyopathy, a condition characterized by cardiac ventricular hypertrabeculation. We examined the prenatal course and subsequent pathologic correlation since ventricular morphogenesis may depend on early muscular contraction and blood flow. The monochorionic-monoamniotic female twin pair was initially identified since one fetus presented with increased nuchal translucency. Complete heart block was later identified in the fetus with nuchal translucency who did not survive after delivery. In contrast, the unaffected twin had normal cardiac studies both prenatally and postnatally. Pathologic analysis of the affected twin demonstrated noncompaction of the left ventricle with dysplasia of the aortic and pulmonary valves. Dissection of the cardiac conduction system disclosed atrioventricular bundle fibrosis. Maternal lupus studies, amniocentesis with karyotype, and studies for 22q11.2 were normal. To test for zygosity, we performed multiple STR marker analysis and found that all markers were shared even using nonblood tissues from the affected twin. These studies demonstrate that monozygotic twins that are monochorionic monoamniotic can be discordant for cardiac noncompaction. The results suggest further investigation into the potential roles of pathologic fibrosis, contractility, and blood flow in cardiac ventricle development. PMID:23636980

  11. Combination of Whole Genome Sequencing, Linkage, and Functional Studies Implicates a Missense Mutation in Titin as a Cause of Autosomal Dominant Cardiomyopathy With Features of Left Ventricular Noncompaction

    PubMed Central

    Hastings, Robert; de Villiers, Carin P.; Hooper, Charlotte; Ormondroyd, Liz; Pagnamenta, Alistair; Lise, Stefano; Salatino, Silvia; Knight, Samantha J.L.; Taylor, Jenny C.; Thomson, Kate L.; Arnold, Linda; Chatziefthimiou, Spyros D.; Konarev, Petr V.; Wilmanns, Matthias; Ehler, Elisabeth; Ghisleni, Andrea; Gautel, Mathias; Blair, Edward; Watkins, Hugh

    2016-01-01

    Background— High throughput next-generation sequencing techniques have made whole genome sequencing accessible in clinical practice; however, the abundance of variation in the human genomes makes the identification of a disease-causing mutation on a background of benign rare variants challenging. Methods and Results— Here we combine whole genome sequencing with linkage analysis in a 3-generation family affected by cardiomyopathy with features of autosomal dominant left ventricular noncompaction cardiomyopathy. A missense mutation in the giant protein titin is the only plausible disease-causing variant that segregates with disease among the 7 surviving affected individuals, with interrogation of the entire genome excluding other potential causes. This A178D missense mutation, affecting a conserved residue in the second immunoglobulin-like domain of titin, was introduced in a bacterially expressed recombinant protein fragment and biophysically characterized in comparison to its wild-type counterpart. Multiple experiments, including size exclusion chromatography, small-angle x ray scattering, and circular dichroism spectroscopy suggest partial unfolding and domain destabilization in the presence of the mutation. Moreover, binding experiments in mammalian cells show that the mutation markedly impairs binding to the titin ligand telethonin. Conclusions— Here we present genetic and functional evidence implicating the novel A178D missense mutation in titin as the cause of a highly penetrant familial cardiomyopathy with features of left ventricular noncompaction. This expands the spectrum of titin’s roles in cardiomyopathies. It furthermore highlights that rare titin missense variants, currently often ignored or left uninterpreted, should be considered to be relevant for cardiomyopathies and can be identified by the approach presented here. PMID:27625337

  12. Next-generation sequencing (NGS) as a fast molecular diagnosis tool for left ventricular noncompaction in an infant with compound mutations in the MYBPC3 gene.

    PubMed

    Schaefer, Elise; Helms, Pauline; Marcellin, Luc; Desprez, Philippe; Billaud, Philippe; Chanavat, Valérie; Rousson, Robert; Millat, Gilles

    2014-03-01

    Left ventricular noncompaction (LVNC) is a clinically heterogeneous disorder characterized by a trabecular meshwork and deep intertrabecular myocardial recesses that communicate with the left ventricular cavity. LVNC is classified as a rare genetic cardiomyopathy. Molecular diagnosis is a challenge for the medical community as the condition shares morphologic features of hypertrophic and dilated cardiomyopathies. Several genetic causes of LVNC have been reported, with variable modes of inheritance, including autosomal dominant and X-linked inheritance, but relatively few responsible genes have been identified. In this report, we describe a case of a severe form of LVNC leading to death at 6 months of life. NGS sequencing using a custom design for hypertrophic cardiomyopathy panel allowed us to identify compound heterozygosity in the MYBPC3 gene (p.Lys505del, p.Pro955fs) in 3 days, confirming NGS sequencing as a fast molecular diagnosis tool. Other studies have reported neonatal presentation of cardiomyopathies associated with compound heterozygous or homozygous MYBPC3 mutations. In this family and in families in which parental truncating MYBPC3 mutations are identified, preimplantation or prenatal genetic screening should be considered as these genotypes leads to neonatal mortality and morbidity.

  13. Noncompaction cardiomyopathy and pregnancy: An alarming coexistence ending in a favourable outcome

    PubMed Central

    Plastiras, Sotiris C; Pamboucas, Constantinos; Toumanidis, Savvas

    2012-01-01

    Noncompaction of the left ventricular myocardium has gained increasing recognition over the past 25 years. This rare disease is caused by the arrest of myocardial morphogenesis. The classical triad of complications are heart failure, arrhythmias, including sudden cardiac death, and systemic embolic events. There is a paucity of data regarding women with left ventricular noncompaction cardiomyopathy and pregnancy outcome. The first report of an uneventful vaginal delivery without deterioration of left ventircular noncompaction cardiomyopathy is presented. PMID:23620702

  14. Noncompaction myocardium in association with type Ib glycogen storage disease.

    PubMed

    Goeppert, Benjamin; Lindner, Martin; Vogel, Monika Nadja; Warth, Arne; Stenzinger, Albrecht; Renner, Marcus; Schnabel, Philipp; Schirmacher, Peter; Autschbach, Frank; Weichert, Wilko

    2012-10-15

    Noncompaction myocardium is a rare disorder assumed to occur as an arrest of the compaction process during the normal development of the heart. Left ventricular noncompaction has been reported to be associated with a variety of cardiac and extracardiac, especially neuromuscular abnormalities. Moreover, it has been suggested that metabolic alterations could be responsible for the noncompaction. However, no association of noncompaction myocardium with type Ib glycogen storage disease (GSD) has been reported so far. Type Ib GSD is due to a defect of a transmembrane protein which results, similar to type Ia GSD, in hypoglycemia, a markedly enlarged liver and, additionally, in neutropenia, recurrent infections, and inflammatory bowel disease. Until now, no muscular or cardiac involvement has been described in type Ib GSD patients. The present case represents the first report of a noncompaction myocardium in a child with type Ib GSD who died of sudden clinical deterioration at the age of four.

  15. Isolated right ventricular failure in hyperthyroidism: a clinical dilemma

    PubMed Central

    McDonough, Ryan J.; Moul, Marvin S.; Beckman, Darrick; Slim, Ahmad M.

    2011-01-01

    We present a unique case of a 42-year-old gentleman with newly diagnosed Graves’ disease and isolated right ventricular failure. Extensive evaluation to include echocardiogram and cardiac catheterization were negative for significant pulmonary hypertension or coronary artery disease as potential etiologies. Hyperthyroid induced vasospasm is a rare but reported clinical entity that serves to be a clinical and diagnostic dilemma. PMID:22049310

  16. Common arterial trunk and ventricular non-compaction in Lrp2 knockout mice indicate a crucial role of LRP2 in cardiac development

    PubMed Central

    Baardman, Maria E.; Zwier, Mathijs V.; Wisse, Lambertus J.; Gittenberger-de Groot, Adriana C.; Kerstjens-Frederikse, Wilhelmina S.; Hofstra, Robert M. W.; Jurdzinski, Angelika; Hierck, Beerend P.; Jongbloed, Monique R. M.; Berger, Rolf M. F.; Plösch, Torsten; DeRuiter, Marco C.

    2016-01-01

    ABSTRACT Lipoprotein-related receptor protein 2 (LRP2) is important for development of the embryonic neural crest and brain in both mice and humans. Although a role in cardiovascular development can be expected, the hearts of Lrp2 knockout (KO) mice have not yet been investigated. We studied the cardiovascular development of Lrp2 KO mice between embryonic day 10.5 (E10.5) and E15.5, applying morphometry and immunohistochemistry, using antibodies against Tfap2α (neural crest cells), Nkx2.5 (second heart field), WT1 (epicardium derived cells), tropomyosin (myocardium) and LRP2. The Lrp2 KO mice display a range of severe cardiovascular abnormalities, including aortic arch anomalies, common arterial trunk (persistent truncus arteriosus) with coronary artery anomalies, ventricular septal defects, overriding of the tricuspid valve and marked thinning of the ventricular myocardium. Both the neural crest cells and second heart field, which are essential for the lengthening and growth of the right ventricular outflow tract, are abnormally positioned in the Lrp2 KO. This explains the absence of the aorto-pulmonary septum, which leads to common arterial trunk and ventricular septal defects. Severe blebbing of the epicardial cells covering the ventricles is seen. Epithelial-mesenchymal transition does occur; however, there are fewer WT1-positive epicardium-derived cells in the ventricular wall as compared to normal, coinciding with the myocardial thinning and deep intertrabecular spaces. LRP2 plays a crucial role in cardiovascular development in mice. This corroborates findings of cardiac anomalies in humans with LRP2 mutations. Future studies should reveal the underlying signaling mechanisms in which LRP2 is involved during cardiogenesis. PMID:26822476

  17. Dual Endothelin Receptor Blockade Abrogates Right Ventricular Remodeling and Biventricular Fibrosis in Isolated Elevated Right Ventricular Afterload

    PubMed Central

    Nielsen, Eva Amalie; Sun, Mei; Honjo, Osami; Hjortdal, Vibeke E.; Redington, Andrew N.; Friedberg, Mark K.

    2016-01-01

    Background Pulmonary arterial hypertension is usually fatal due to right ventricular failure and is frequently associated with co-existing left ventricular dysfunction. Endothelin-1 is a powerful pro-fibrotic mediator and vasoconstrictor that is elevated in pulmonary arterial hypertension. Endothelin receptor blockers are commonly used as pulmonary vasodilators, however their effect on biventricular injury, remodeling and function, despite elevated isolated right ventricular afterload is unknown. Methods Elevated right ventricular afterload was induced by progressive pulmonary artery banding. Seven rabbits underwent pulmonary artery banding without macitentan; 13 received pulmonary artery banding + macitentan; and 5 did not undergo inflation of the pulmonary artery band (sham-operated controls). Results: Right and left ventricular collagen content was increased with pulmonary artery banding compared to sham-operated controls and ameliorated by macitentan. Right ventricular fibrosis signaling (connective tissue growth factor and endothelin-1 protein levels); extra-cellular matrix remodeling (matrix-metalloproteinases 2 and 9), apoptosis and apoptosis-related peptides (caspases 3 and 8) were increased with pulmonary artery banding compared with sham-operated controls and decreased with macitentan. Conclusion Isolated right ventricular afterload causes biventricular fibrosis, right ventricular apoptosis and extra cellular matrix remodeling, mediated by up-regulation of endothelin-1 and connective tissue growth factor signaling. These pathological changes are ameliorated by dual endothelin receptor blockade despite persistent elevated right ventricular afterload. PMID:26765263

  18. Acquired Fontan paradox in isolated right ventricular cardiomyopathy.

    PubMed

    Saran, Mahim; Sivasubramonian, Sivasankaran; Abhilash, Sreevilasam P; Tharakan, Jaganmohan A

    2016-01-01

    A 44-year-old woman presented with features of congestive heart failure. Echocardiography revealed severe right ventricular dysfunction along with passive minimally pulsatile pulmonary blood flow suggesting very high systemic venous pressures. This was confirmed with cardiac catheterization in which the pressures of superior vena cava and inferior vena cava (19 mmHg) were higher than the pulmonary artery pressures (17 mmHg). Elevation of systemic venous pressures above the pulmonary venous pressures, Fontan paradox, to drive the forward flow, is a specific feature of artificially created cavopulmonary shunts. Late stage of isolated right ventricular cardiomyopathy resulted in the spontaneous evolution of Fontan circulation with a nonfunctional right ventricle in this patient. PMID:27625525

  19. Acquired Fontan paradox in isolated right ventricular cardiomyopathy

    PubMed Central

    Saran, Mahim; Sivasubramonian, Sivasankaran; Abhilash, Sreevilasam P; Tharakan, Jaganmohan A

    2016-01-01

    A 44-year-old woman presented with features of congestive heart failure. Echocardiography revealed severe right ventricular dysfunction along with passive minimally pulsatile pulmonary blood flow suggesting very high systemic venous pressures. This was confirmed with cardiac catheterization in which the pressures of superior vena cava and inferior vena cava (19 mmHg) were higher than the pulmonary artery pressures (17 mmHg). Elevation of systemic venous pressures above the pulmonary venous pressures, Fontan paradox, to drive the forward flow, is a specific feature of artificially created cavopulmonary shunts. Late stage of isolated right ventricular cardiomyopathy resulted in the spontaneous evolution of Fontan circulation with a nonfunctional right ventricle in this patient. PMID:27625525

  20. Isolated Right Ventricular Infarction Mimicking Anterior ST-Segment Elevation

    PubMed Central

    Oktay, Veysel; Coskun, Ugur; Yildiz, Ahmet; Gurmen, Tevfik

    2016-01-01

    Acute coronary syndromes in patients with presence of ST-segment elevation in the anterior precordial leads indicates left anterior descending coronary artery occlusion. However, anterior ST-segment elevation has also been described in right ventricular myocardial infarction and is thought to be due to right coronary artery (RCA) occlusion. We present a rare case of isolated RVMI presenting with anterior ST-segment elevation due to proximal occlusion of a right coronary artery that was treated by primary coronary angioplasty. Primary coronary angioplasty and stenting of this artery was performed resulting in resolution of the chest pain and ST- segment elevation. PMID:27190867

  1. Non-compaction cardiomyopathy in an asymptomatic athlete.

    PubMed

    Manus, Margaret Kapor; Roy, Satyajeet; Stag, Rosemarie; Hyman, Daniel

    2016-01-01

    Prevention of sudden cardiac death in athletes requires the screening and recognition of pathologies that often remain clinically silent for years until provoked by a physiologic stressor. This can result in the manifestation of disease and even death. Left ventricular non-compaction cardiomyopathy (LVNC), newly classified as a distinct entity arising in the adult population, is a cardiomyopathy that at initial presentation can manifest as a wide spectrum of symptoms from asymptomatic to ventricular arrhythmias, systemic embolism and even sudden cardiac death. We present the case of an asymptomatic athlete found to have LVNC and discuss the implications this finding may have on sports participation. PMID:27535732

  2. Noncompaction and embolic myocardial infarction: the importance of oral anticoagulation.

    PubMed

    Pulignano, Giovanni; Tinti, Maria Denitza; Tolone, Stefano; Musto, Carmine; De Lio, Lucia; Pino, Paolo Giuseppe; Minardi, Giovanni; Violini, Roberto; Uguccioni, Massimo

    2015-01-01

    Left ventricular noncompaction (LVNC) is characterized by left ventricular (LV) hypertrabeculations and is associated with heart failure, arrhythmias and embolism. We report the case of a 67-year-old LVNC patient, under oral anticoagulation (OAC) therapy for apical thrombosis. After she discontinued OAC, the thrombus involved almost the whole of the left ventricle; in a few months her condition worsened, requiring hospitalization, and despite heparin infusion she experienced myocardial infarction (MI), caused by embolic occlusion of the left anterior descending artery. Although infrequent as a complication of LVNC, and usually attributable to microvascular dysfunction, in this case MI seems due to coronary thromboembolism from dislodged thrombotic material in the left ventricle.

  3. Abnormal myocardial strain rate in noncompaction of the left ventricle.

    PubMed

    Williams, R Ian; Masani, Navroz D; Buchalter, Maurice B; Fraser, Alan G

    2003-03-01

    A 28-year-old woman presented in the second trimester of pregnancy with palpitations and left heart failure. Transthoracic echocardiography showed features consistent with isolated noncompaction of the left ventricle. Doppler tissue echocardiography with strain-rate imaging revealed unique appearances of paradoxical alternating bands of compression and expansion throughout systole and diastole. These features may be pathognomonic for this disease.

  4. Isolated Left Ventricular Apical Hypoplasia: Reporting a Case With Mild Manifestations and Different Echocardiography Features

    PubMed Central

    Mirdamadi, Ahmad; Ashrafi, Samira

    2016-01-01

    Introduction Isolated left ventricular apical hypoplasia is an unusual type of cardiomyopathy that presents with different clinical manifestations according to the age of the disease, ranging from no symptoms in children to congestive heart failure, pulmonary edema, or even malignant tachycardia in adults. To our knowledge, only a few cases of isolated left ventricular apical hypoplasia have been reported in Asian adults. Case Presentation Herein, we described an adult case of isolated left ventricular apical hypoplasia referred to our heart center in Isfahan, Iran in 2015 with a complaint of mild dyspnea with the absence of obvious fatty tissue in the heart’s apex and an absence of any shunt, which are common findings in patients with this phenomenon. Conclusions Patients faced with isolated left ventricular apical hypoplasia should be monitored by echocardiography because of this disease’s possible progressive trend to life-threatening consequences. PMID:27800175

  5. Stimulation of isolated ventricular myocytes within an open architecture microarray.

    PubMed

    Klauke, Norbert; Smith, Godfrey L; Cooper, Jonathan M

    2005-03-01

    This paper is concerned with the physiological responses of single heart cells within microfluidic chambers, in response to stimulation by integrated microelectrodes. To enable these investigations, which included the measurement of action potential duration, intracellular Ca2+ and cell shortening, a series of microfluidic chambers (50 microm wide, 180 microm long, 400 microm high, 500 microm pitch) and connecting channels (200 microm wide, 5000 microm long, 50 microm high, 500 microm pitch) were replica-moulded into the silicone elastomer, polydimethylsiloxane (PDMS). The structures were formed against a master of posts and lines, photolithograhically patterned into the high aspect ratio photoresist SU-8. The chambers within the slab of PDMS were aligned against pairs of stimulating gold microelectrodes (50 microm long, 20 microm wide, 0.1-10 microm thick, 180 microm apart) patterned on a microscope coverslip base, thus defining cavities of approximately 4 nL volume. The assembly was filled with physiological saline and single isolated rabbit ventricular myocytes were introduced by micropipetting, thus creating limited volumes of saline above individual myocytes that could be varied between 4 nL and > or = 4 microL. The application of transient current pulses to the cells via the electrodes caused transient contractions with constant amplitude (recorded as changes in sarcomere length), confirming that excitation contraction coupling (EC coupling) remained functional in these limited volumes. Continuous monitoring of the intracellular Ca2+ (using calcium sensitive dyes) showed, that in the absence of bath perfusion, the amplitude of the transients remained constant for approximately 3 min in the 4-nL volume and approximately 20 min for the 4 microL volume. Beyond this time, the cells became unexcitable until the bath was renewed. The action potential duration (APD) was recorded at stimulation frequencies of 1 Hz and 0.5 Hz using potential sensitive dyes and was

  6. Right Ventricular Outflow Tract Obstruction Caused by Isolated Sinus of Valsalva Aneurysm.

    PubMed

    Abu Saleh, Walid K; Lin, Chun Huie; Reardon, Michael J; Ramlawi, Basel

    2016-08-01

    Isolated sinus of Valsalva aneurysm is a rare occurrence, with an incidence of <1.5% among congenital heart disease repairs in the world. We recount the case of a 64-year-old man who presented with right-sided heart failure symptoms caused by a severely dilated right coronary sinus of Valsalva aneurysm that substantially obstructed the right ventricular outflow tract. Successful surgical repair involved right ventricular outflow tract resection and subcoronary patch repair. PMID:27547152

  7. The non-compact Weyl equation

    NASA Astrophysics Data System (ADS)

    Doikou, Anastasia; Ioannidou, Theodora

    2011-04-01

    A non-compact version of the Weyl equation is proposed, based on the infinite dimensional spin zero representation of the mathfrak{s}{mathfrak{l}_2} algebra. Solutions of the aforementioned equation are obtained in terms of the Kummer functions. In this context, we discuss the ADHMN approach in order to construct the corresponding non-compact BPS monopoles.

  8. [Permanent cardiac stimulation in a patient with isolated dextrocardia and ventricular septal defect].

    PubMed

    Słowiński, S; Derlaga, B; Kapusta, J

    A case of pacemaker implantation because of acquired atrioventricular block third degree in woman aged 39 years with rare isolated dextrocardia with inversion of cardiac ventricles, compensatory transposition of both aorta and pulmonary artery, and ventricular septal defect. The end of electrode has wedged in the apex of the arterial ventricle. Following pacemaker implantation, patients clinical course of gynaecological operation was uneventful.

  9. Mechanisms by which calcium receptor stimulation modifies electromechanical coupling in isolated ventricular cardiomyocytes.

    PubMed

    Schreckenberg, Rolf; Dyukova, Elena; Sitdikova, Guzel; Abdallah, Yaser; Schlüter, Klaus-Dieter

    2015-02-01

    The calcium-sensing receptor (CaR) is widely expressed throughout the entire cardiovascular system and is capable of activating signaling pathways in different cells. Alongside calcium, the CaR also responds to physiological polycations such as putrescine underlining a participation in physiological and pathophysiological processes. Here, we aimed to determine mechanisms as to how CaR activation affects the contractile responsiveness of ventricular cardiomyocytes under basal and stimulated conditions. For that purpose, cardiac myocytes from 3-month-old male Wistar rats were isolated, and the acute effects of an antagonist (NPS2390), agonists (putrescine and gadolinium), or of downregulation of the CaR by siRNA on cell shortening were recorded in a cell-edge-detection system. In addition, experiments were performed on muscle stripes and Langendorff preparations. Mechanistic insights were taken from calcium transients of beating fura-2 AM-loaded cardiomyocytes and western blots. Isolated ventricular cardiomyocytes constitutively express CaR. The expression in the atria is less pronounced. Acute inhibition of CaR reduced basal cell shortening of ventricular myocytes at nearly physiological levels of extracellular calcium. Inhibition of CaR strongly reduced contractility of ventricular muscle stripes but not of atria. Activation of CaR by putrescine and gadolinium influences the contractile responsiveness of isolated cardiomyocytes. Increased calcium mobilization from the sarcoplasmic reticulum via an IP3-dependent mechanism was responsible for amplified systolic calcium transients and a subsequent improvement in cell shortening. Alongside with these effects, activation of CaR increased relaxation velocity of the cells. In conclusion, ventricular CaR expression affects contractile parameters of ventricular heart muscle cells and modifies electromechanical coupling of cardiomyocytes.

  10. Echocardiographic Evaluation of Left Ventricular Function, Mass and Wall Stress in Children with Isolated Ventricular Septal Defect

    PubMed Central

    Waggoner, Alan D.; Nouri, Soraya; Schaffer, Michael S.; Chen, Su-Chiung

    1985-01-01

    M-Mode echocardiography was performed in 22 normal children and 22 children with ventricular septal defects. Left ventricular and left atrial chamber dimensions and wall thicknesses were measured in all patients. Utilizing these data, indices of left ventricular function were derived: shortening fraction, velocity of fiber shortening, peak diastolic fiber lengthening, end-systolic wall stress, radius thickness ratio, and ventricular mass. The results showed that ventricular septal defect was associated with enlarged left ventricular and atrial dimensions and increased shortening fraction, but that velocity of shortening and early diastolic lengthening remained normal. Left ventricular mass was increased, thus maintaining normal wall stress and radius/thickness ratio. Cardiac failure complicating ventricular septal defect was associated with enlarged left ventricular and atrial dimensions (indexed for weight). Ventricular mass, wall stress and function, however, were similar in subjects with ventricular septal defect, with or without cardiac failure. Since left ventricular mass was adequate to maintain wall stress and function in subjects with heart failure, other factors were presumably responsible for heart failure complicating ventricular septal defect. PMID:15227026

  11. Sustained vortex-like waves in normal isolated ventricular muscle.

    PubMed Central

    Davidenko, J M; Kent, P F; Chialvo, D R; Michaels, D C; Jalife, J

    1990-01-01

    Sustained reentrant excitation may be initiated in small (20 x 20 x less than 0.6 mm) preparations of normal ventricular muscle. A single appropriately timed premature electrical stimulus applied perpendicularly to the wake of a propagating quasiplanar wavefront gives rise to circulation of self-sustaining excitation waves, which pivot at high frequency (5-7 Hz) around a relatively small "phaseless" region. Such a region develops only very low amplitude depolarizations. Once initiated, most episodes of reentrant activity last indefinitely but can be interrupted by the application of an appropriately timed electrical stimulus. The entire course of the electrical activity is visualized with high temporal and spatial resolution, as well as high signal-to-noise ratio, using voltage-sensitive dyes and optical mapping. Two- and three-dimensional graphics of the fluorescence changes recorded by a 10 x 10 photodiode array from a surface of 12 x 12 mm provide sequential images (every msec) of voltage distribution during a reentrant vortex. The results suggest that two-dimensional vortex-like reentry in cardiac muscle is analogous to spiral waves in other biological and chemical excitable media. Images PMID:2247448

  12. Pathologic features of dilated cardiomyopathy with localized noncompaction in a child with deletion 1p36 syndrome.

    PubMed

    Pearce, F Bennett; Litovsky, Silvio H; Dabal, Robert J; Robin, Nathaniel; Dure, Leon J; George, James F; Kirklin, James K

    2012-01-01

    Dilated cardiomyopathy and ventricular noncompaction have been reported in association with deletion 1p36 syndrome. Previous descriptions include echocardiographic and/or gross pathologic descriptions. There are no previous reports of microscopic findings. We report a case with descriptions of echocardiographic, gross pathologic, and microscopic findings.

  13. Calcium current in isolated neonatal rat ventricular myocytes.

    PubMed Central

    Cohen, N M; Lederer, W J

    1987-01-01

    1. Calcium currents (ICa) from neonatal rat ventricular heart muscle cells grown in primary culture were examined using the 'whole-cell' voltage-clamp technique (Hamill, Marty, Neher, Sakmann & Sigworth, 1981). Examination of ICa was limited to one calcium channel type, 'L' type (Nilius, Hess, Lansman & Tsien, 1985), by appropriate voltage protocols. 2. We measured transient and steady-state components of ICa, and could generally describe ICa in terms of the steady-state activation (d infinity) and inactivation (f infinity) parameters. 3. We observed that the reduction of ICa by the calcium channel antagonist D600 can be explained by both a shift of d infinity to more positive potentials as well as a slight reduction of ICa conductance. D600 did not significantly alter either the rate of inactivation of ICa or the voltage dependence of f infinity. 4. The calcium channel modulator BAY K8644 shifted both d infinity and f infinity to more negative potentials. Additionally, BAY K8644 increased the rate of inactivation at potentials between +5 and +55 mV. Furthermore, BAY K8644 also increased ICa conductance, a change consistent with a promotion of 'mode 2' calcium channel activity (Hess, Lansman & Tsien, 1984). 5. We conclude that, as predicted by d infinity and f infinity, there is a significant steady-state component of ICa ('window current') at plateau potentials in neonatal rat heart cells. Modulation of the steady-state and transient components of ICa by various agents can be attributed both to specific alterations in d infinity and f infinity and to more complicated alterations in the mode of calcium channel activity. PMID:2451004

  14. Congenital isolated cleft mitral valve leaflet and apical muscular ventricular septal defect in a Holstein calf.

    PubMed

    Depenbrock, Sarah M; Visser, Lance C; Kohnken, Rebecca A; Russell, Duncan S; Simpson, Katharine M; Bonagura, John D

    2015-09-01

    A 5-week-old Holstein heifer calf presented for emergency treatment of signs referable to gastrointestinal disease and hypovolemic shock. Fluid resuscitation uncovered clinical signs of primary cardiac disease and echocardiography revealed multiple congenital cardiac defects. Malformations included a cleft anterior mitral valve leaflet resembling an isolated cleft mitral valve and an apically-located muscular ventricular septal defect. The echocardiographic and postmortem findings associated with these defects are presented and discussed in this report.

  15. Overreaction to noncompaction in a patient with ankylosing spondylitis, Parkinson disease, migraine and myopathy.

    PubMed

    Stöllberger, Claudia; Stix, Alexander; Finsterer, Josef

    2011-07-01

    A patient with ankylosing spondylitis, migraine, Parkinson syndrome, renal insufficiency and myopathy, received an implantable-cardioverter-defibrillator because of asymptomatic left ventricular hypertrabeculation/noncompaction as primary prophylaxis against sudden cardiac death. Inadvertently the ventricular lead was placed in a cardiac vein, the patient suffered from pericardial effusion and it was impossible to remove the lead. Implantation of an implantable-cardioverter-defibrillator simply upon the presence of LVHT appears not justified and may be more harmful than beneficial. Studies about the risk of SCD in adults with LVHT are necessary and will hopefully clarify if primary prevention of SCD is indicated.

  16. The effect of hexane on the ventricular fibrillation threshold of the isolated perfused rat heart.

    PubMed

    Khedun, S M; Maharaj, B; Leary, W P; Lockett, C J

    1992-01-01

    This investigation was conducted to determine the influence of hexane on the ventricular fibrillation threshold of the isolated perfused rat heart and myocardial electrolyte levels. Ventricular fibrillation threshold was measured using the Langendorff perfusion apparatus. Heart rate was measured by a universal digital counter and the cardiac flow by collecting the outflow of the heating chamber below the heart into a graduated measuring cylinder. Magnesium and zinc were measured by atomic absorption spectrophotometry and potassium by flame photometry. Two groups of rats were studied; those in the experimental group were given 0.2 ml of hexane and the control group 0.2 ml olive oil subcutaneously for 90 days. Their hearts were removed under anaesthesia. Half of the experimental and control hearts were mounted on the Langendorff perfusion apparatus and the heart rate, coronary flow and ventricular fibrillation threshold were measured. The hearts of the other half were used to measure myocardial electrolyte levels. In the experimental group the ventricular fibrillation threshold decreased (4.72 (S.D. +/- 1.87) vs 9.48 (S.D. +/- 2.98); P less than 0.001). There was no change in the coronary flow and heart rate in between the groups. The mean myocardial potassium levels (2586 (S.D. +/- 162) vs 2968 (S.D. +/- 218) micrograms/g; P less than 0.001), magnesium levels (164 (S.D. +/- 28) vs 208 (S.D. +/- 18) micrograms/g; P less than 0.001) and zinc levels (19.6 (S.D. +/- 4) vs 33.8 (S.D. +/- 6.8) micrograms/g; P less than 0.001) were significantly lower in the hexane-treated group compared to controls. Hexane, a constituent of glue and benzine, is cardiotoxic; marked derangement in myocardial electrolytes and a reduced ventricular fibrillation threshold, indicating an increased myocardial vulnerability to arrhythmias, was noted in the experimental animals. PMID:1729763

  17. Differential Expression Levels of Integrin α6 Enable the Selective Identification and Isolation of Atrial and Ventricular Cardiomyocytes

    PubMed Central

    Wiencierz, Anne Maria; Kernbach, Manuel; Ecklebe, Josephine; Monnerat, Gustavo; Tomiuk, Stefan; Raulf, Alexandra; Christalla, Peter; Malan, Daniela; Hesse, Michael; Bosio, Andreas; Fleischmann, Bernd K.; Eckardt, Dominik

    2015-01-01

    Rationale Central questions such as cardiomyocyte subtype emergence during cardiogenesis or the availability of cardiomyocyte subtypes for cell replacement therapy require selective identification and purification of atrial and ventricular cardiomyocytes. However, current methodologies do not allow for a transgene-free selective isolation of atrial or ventricular cardiomyocytes due to the lack of subtype specific cell surface markers. Methods and Results In order to develop cell surface marker-based isolation procedures for cardiomyocyte subtypes, we performed an antibody-based screening on embryonic mouse hearts. Our data indicate that atrial and ventricular cardiomyocytes are characterized by differential expression of integrin α6 (ITGA6) throughout development and in the adult heart. We discovered that the expression level of this surface marker correlates with the intracellular subtype-specific expression of MLC-2a and MLC-2v on the single cell level and thereby enables the discrimination of cardiomyocyte subtypes by flow cytometry. Based on the differential expression of ITGA6 in atria and ventricles during cardiogenesis, we developed purification protocols for atrial and ventricular cardiomyocytes from mouse hearts. Atrial and ventricular identities of sorted cells were confirmed by expression profiling and patch clamp analysis. Conclusion Here, we introduce a non-genetic, antibody-based approach to specifically isolate highly pure and viable atrial and ventricular cardiomyocytes from mouse hearts of various developmental stages. This will facilitate in-depth characterization of the individual cellular subsets and support translational research applications. PMID:26618511

  18. Noncompaction and Dilated Cardiomyopathy in a Patient with Schizophrenia

    PubMed Central

    Stöllberger, Claudia

    2016-01-01

    Objectives. Psychosis and left ventricular hypertrabeculation (or noncompaction) (LVHT) have not been described in the same patient. Here we report a patient with a long-term history of schizophrenia who was later diagnosed with dilated cardiomyopathy (dCMP) and LVHT. Case Report. A 47-year-old Caucasian male developed nondifferentiated schizophrenia at the age of 26 y. Since the age of 33 y he was regularly drinking alcohol. At the age of 47 y he developed heart failure. Transthoracic echocardiography showed an enlarged left ventricle, reduced systolic function, and surprisingly LVHT in the apical segment. Additionally, the left atrium was enlarged, the right ventricular cavities were mildly enlarged, and there were pulmonary hypertension and a small pericardial effusion. Cardiac MRI confirmed the echocardiographic findings. Since coronary angiography was normal, dilated cardiomyopathy was additionally diagnosed. Since he was taking clozapine during years, dilated cardiomyopathy could be due to not only alcohol consumption but also the long-term neuroleptic medication. Conclusions. LVHT may be associated with nondifferentiated psychosis. Management of LVHT is challenging in patients with psychosis due to poor compliance and adherence of these patients. Patients with LVHT and psychosis need particular attention since they usually take cardiotoxic drugs for a long time, which may further deteriorate the prognosis of LVHT. PMID:27547471

  19. Streptozotocin-induced diabetes prolongs twitch duration without affecting the energetics of isolated ventricular trabeculae

    PubMed Central

    2014-01-01

    Background Diabetes induces numerous electrical, ionic and biochemical defects in the heart. A general feature of diabetic myocardium is its low rate of activity, commonly characterised by prolonged twitch duration. This diabetes-induced mechanical change, however, seems to have no effect on contractile performance (i.e., force production) at the tissue level. Hence, we hypothesise that diabetes has no effect on either myocardial work output or heat production and, consequently, the dependence of myocardial efficiency on afterload of diabetic tissue is the same as that of healthy tissue. Methods We used isolated left ventricular trabeculae (streptozotocin-induced diabetes versus control) as our experimental tissue preparations. We measured a number of indices of mechanical (stress production, twitch duration, extent of shortening, shortening velocity, shortening power, stiffness, and work output) and energetic (heat production, change of enthalpy, and efficiency) performance. We calculated efficiency as the ratio of work output to change of enthalpy (the sum of work and heat). Results Consistent with literature results, we showed that peak twitch stress of diabetic tissue was normal despite suffering prolonged duration. We report, for the first time, the effect of diabetes on mechanoenergetic performance. We found that the indices of performance listed above were unaffected by diabetes. Hence, since neither work output nor change of enthalpy was affected, the efficiency-afterload relation of diabetic tissue was unaffected, as hypothesised. Conclusions Diabetes prolongs twitch duration without having an effect on work output or heat production, and hence efficiency, of isolated ventricular trabeculae. Collectively, our results, arising from isolated trabeculae, reconcile the discrepancy between the mechanical performance of the whole heart and its tissues. PMID:24731754

  20. Infinitely many singular interactions on noncompact manifolds

    SciTech Connect

    Kaynak, Burak Tevfik Turgut, O. Teoman

    2015-05-15

    We show that the ground state energy is bounded from below when there are infinitely many attractive delta function potentials placed in arbitrary locations, while all being separated at least by a minimum distance, on two dimensional non-compact manifold. To facilitate the reading of the paper, we first present the arguments in the setting of Cartan–Hadamard manifolds and then subsequently discuss the general case. For this purpose, we employ the heat kernel techniques as well as some comparison theorems of Riemannian geometry, thus generalizing the arguments in the flat case following the approach presented in Albeverio et al. (2004). - Highlights: • Schrödinger-operator for infinitely many singular interactions on noncompact manifolds. • Proof of the finiteness of the ground-state energy.

  1. Stimulation of single isolated adult ventricular myocytes within a low volume using a planar microelectrode array.

    PubMed

    Klauke, Norbert; Smith, Godfrey L; Cooper, Jon

    2003-09-01

    Microchannels (40- microm wide, 10- microm high, 10-mm long, 70- microm pitch) were patterned in the silicone elastomer, polydimethylsiloxane on a microscope coverslip base. Integrated within each microchamber were individually addressable stimulation electrodes (40- microm wide, 20- microm long, 100-nm thick) and a common central pseudo-reference electrode (60- microm wide, 500- microm long, 100-nm thick). Isolated rabbit ventricular myocytes were introduced into the chamber by micropipetting and subsequently capped with a layer of mineral oil, thus creating limited volumes of saline around individual myocytes that could be varied from 5 nL to 100 pL. Excitation contraction coupling was studied by monitoring myocyte shortening and intracellular Ca(2+) transients (using Fluo-3 fluorescence). The amplitude of stimulated myocyte shortening and Ca(2+) transients remained constant for 90 min in the larger volume (5 nL) configuration, although the shortening (but not the Ca(2+) transient) amplitude gradually decreased to 20% of control within 60 min in the low volume (100 pL) arrangement. These studies indicate a lower limit for the extracellular volume required to stimulate isolated adult cardiac myocytes. Whereas this arrangement could be used to create a screening assay for drugs, individual microchannels (100 pL) can also be used to study the effects of limited extracellular volume on the contractility of single cardiac myocytes.

  2. Stimulation of Single Isolated Adult Ventricular Myocytes within a Low Volume Using a Planar Microelectrode Array

    PubMed Central

    Klauke, Norbert; Smith, Godfrey L.; Cooper, Jon

    2003-01-01

    Microchannels (40-μm wide, 10-μm high, 10-mm long, 70-μm pitch) were patterned in the silicone elastomer, polydimethylsiloxane on a microscope coverslip base. Integrated within each microchamber were individually addressable stimulation electrodes (40-μm wide, 20-μm long, 100-nm thick) and a common central pseudo-reference electrode (60-μm wide, 500-μm long, 100-nm thick). Isolated rabbit ventricular myocytes were introduced into the chamber by micropipetting and subsequently capped with a layer of mineral oil, thus creating limited volumes of saline around individual myocytes that could be varied from 5 nL to 100 pL. Excitation contraction coupling was studied by monitoring myocyte shortening and intracellular Ca2+ transients (using Fluo-3 fluorescence) . The amplitude of stimulated myocyte shortening and Ca2+ transients remained constant for 90 min in the larger volume (5 nL) configuration, although the shortening (but not the Ca2+ transient) amplitude gradually decreased to 20% of control within 60 min in the low volume (100 pL) arrangement. These studies indicate a lower limit for the extracellular volume required to stimulate isolated adult cardiac myocytes. Whereas this arrangement could be used to create a screening assay for drugs, individual microchannels (100 pL) can also be used to study the effects of limited extracellular volume on the contractility of single cardiac myocytes. PMID:12944291

  3. Pharmacological inhibition of IK1 by PA-6 in isolated rat hearts affects ventricular repolarization and refractoriness.

    PubMed

    Skarsfeldt, Mark A; Carstensen, Helena; Skibsbye, Lasse; Tang, Chuyi; Buhl, Rikke; Bentzen, Bo H; Jespersen, Thomas

    2016-04-01

    The inwardly rectifying potassium current (IK 1) conducted through Kir2.X channels contribute to repolarization of the cardiac action potential and to stabilization of the resting membrane potential in cardiomyocytes. Our aim was to investigate the effect of the recently discovered IK 1 inhibitor PA-6 on action potential repolarization and refractoriness in isolated rat hearts. Transiently transfected HEK-293 cells expressing IK 1 were voltage-clamped with ramp protocols. Langendorff-perfused heart experiments were performed on male Sprague-Dawley rats, effective refractory period, Wenckebach cycle length, and ventricular effective refractory period were determined following 200 nmol/L PA-6 perfusion. 200 nmol/L PA-6 resulted in a significant time-latency in drug effect on the IK 1 current expressed in HEK-293 cells, giving rise to a maximal effect at 20 min. In the Langendorff-perfused heart experiments, PA-6 prolonged the ventricular action potential duration at 90% repolarization (from 41.8 ± 6.5 msec to 72.6 ± 21.1 msec, 74% compared to baseline, P < 0.01, n = 6). In parallel, PA-6 significantly prolonged the ventricular effective refractory period compared to baseline (from 34.8 ± 4.6 msec to 58.1 ± 14.7 msec, 67%, P < 0.01, n = 6). PA-6 increased the short-term beat-to-beat variability and ventricular fibrillation was observed in two of six hearts. Neither atrial ERP nor duration of atrial fibrillation was altered following PA-6 application. The results show that pharmacological inhibition of cardiac IK 1 affects ventricular action potential repolarization and refractoriness and increases the risk of ventricular arrhythmia in isolated rat hearts. PMID:27117805

  4. Pharmacological inhibition of IK1 by PA-6 in isolated rat hearts affects ventricular repolarization and refractoriness.

    PubMed

    Skarsfeldt, Mark A; Carstensen, Helena; Skibsbye, Lasse; Tang, Chuyi; Buhl, Rikke; Bentzen, Bo H; Jespersen, Thomas

    2016-04-01

    The inwardly rectifying potassium current (IK 1) conducted through Kir2.X channels contribute to repolarization of the cardiac action potential and to stabilization of the resting membrane potential in cardiomyocytes. Our aim was to investigate the effect of the recently discovered IK 1 inhibitor PA-6 on action potential repolarization and refractoriness in isolated rat hearts. Transiently transfected HEK-293 cells expressing IK 1 were voltage-clamped with ramp protocols. Langendorff-perfused heart experiments were performed on male Sprague-Dawley rats, effective refractory period, Wenckebach cycle length, and ventricular effective refractory period were determined following 200 nmol/L PA-6 perfusion. 200 nmol/L PA-6 resulted in a significant time-latency in drug effect on the IK 1 current expressed in HEK-293 cells, giving rise to a maximal effect at 20 min. In the Langendorff-perfused heart experiments, PA-6 prolonged the ventricular action potential duration at 90% repolarization (from 41.8 ± 6.5 msec to 72.6 ± 21.1 msec, 74% compared to baseline, P < 0.01, n = 6). In parallel, PA-6 significantly prolonged the ventricular effective refractory period compared to baseline (from 34.8 ± 4.6 msec to 58.1 ± 14.7 msec, 67%, P < 0.01, n = 6). PA-6 increased the short-term beat-to-beat variability and ventricular fibrillation was observed in two of six hearts. Neither atrial ERP nor duration of atrial fibrillation was altered following PA-6 application. The results show that pharmacological inhibition of cardiac IK 1 affects ventricular action potential repolarization and refractoriness and increases the risk of ventricular arrhythmia in isolated rat hearts.

  5. Isolated congenital cardiac diverticulum originating from the left ventricular apex: Report of a pediatric case

    PubMed Central

    Uysal, Fahrettin; Bostan, Ozlem Mehtap; Toprak, Muhammed Hamza Halil; Signak, Isik Senkaya; Cil, Ergun

    2016-01-01

    Congenital ventricular diverticulum is a rare cardiac anomaly defined as a localized protrusion of the ventricular free wall. Although, it is usually asymptomatic, complications such as embolism, infective endocarditis, and arrhythmias can occur. The diagnosis can be made by echocardiography, cardiac magnetic resonance imaging, or catheter angiography. Surgical resection is the treatment of choice in symptomatic patients, whereas the management of asymptomatic patients often represents a therapeutic dilemma. We report here, a 9-month-old patient with asymptomatic congenital left ventricular (LV) diverticulum associated with epigastric hernia. PMID:27212863

  6. Non-compact nonlinear sigma models

    NASA Astrophysics Data System (ADS)

    de Rham, Claudia; Tolley, Andrew J.; Zhou, Shuang-Yong

    2016-09-01

    The target space of a nonlinear sigma model is usually required to be positive definite to avoid ghosts. We introduce a unique class of nonlinear sigma models where the target space metric has a Lorentzian signature, thus the associated group being non-compact. We show that the would-be ghost associated with the negative direction is fully projected out by 2 second-class constraints, and there exist stable solutions in this class of models. This result also has important implications for Lorentz-invariant massive gravity: There exist stable nontrivial vacua in massive gravity that are free from any linear vDVZ-discontinuity and a Λ2 decoupling limit can be defined on these vacua.

  7. Itraconazole decreases left ventricular contractility in isolated rabbit heart: Mechanism of action

    SciTech Connect

    Qu, Yusheng; Fang, Mei; Gao, BaoXi; Amouzadeh, Hamid R.; Li, Nianyu; Narayanan, Padma; Acton, Paul; Lawrence, Jeff; Vargas, Hugo M.

    2013-04-15

    Itraconazole (ITZ) is an approved antifungal agent that carries a “black box warning” in its label regarding a risk of negative cardiac inotropy based on clinical findings. Since the mechanism of the negative inotropic effect is unknown, we performed a variety of preclinical and mechanistic studies to explore the pharmacological profile of ITZ and understand the negative inotropic mechanism. ITZ was evaluated in: (1) an isolated rabbit heart (IRH) preparation using Langendorff retrograde perfusion; (2) ion channel studies; (3) a rat heart mitochondrial function profiling screen; (4) a mitochondrial membrane potential (MMP) assay; (5) in vitro pharmacology profiling assays (148 receptors, ion channels, transporters, and enzymes); and (6) a kinase selectivity panel (451 kinases). In the IRH, ITZ decreased cardiac contractility (> 30%) at 0.3 μM, with increasing effect at higher concentrations, which indicated a direct negative inotropic effect upon the heart. It also decreased heart rate and coronary flow (≥ 1 μM) and prolonged PR/QRS intervals (3 μM). In mechanistic studies, ITZ inhibited the cardiac NaV channel (IC{sub 50}: 4.2 μM) and was devoid of any functional inhibitory effect at the remaining pharmacological targets. Lastly, ITZ did not affect MMP, nor interfere with mitochondrial enzymes or processes involved with fuel substrate utilization or energy formation. Overall, the cardiovascular and mechanistic data suggest that ITZ-induced negative inotropy is a direct effect on the heart, in addition, the potential involvement of mitochondria function and L-type Ca{sup 2+} channels are eliminated. The exact mechanism underlying the negative inotropy is uncertain, and requires further study. - Highlights: ► Effect of itraconazole (ITZ) was assessed in the isolated rabbit heart (IRH) assay. ► ITZ decreased ventricular contractility in IRH, indicating a direct effect. ► IC{sub 50} of ITZ on L-type I{sub Ca} was greater than 30 μM, on I{sub Na} was 4

  8. Ventricular filling slows epicardial conduction and increases action potential duration in an optical mapping study of the isolated rabbit heart

    NASA Technical Reports Server (NTRS)

    Sung, Derrick; Mills, Robert W.; Schettler, Jan; Narayan, Sanjiv M.; Omens, Jeffrey H.; McCulloch, Andrew D.; McCullough, A. D. (Principal Investigator)

    2003-01-01

    INTRODUCTION: Mechanical stimulation can induce electrophysiologic changes in cardiac myocytes, but how mechanoelectric feedback in the intact heart affects action potential propagation remains unclear. METHODS AND RESULTS: Changes in action potential propagation and repolarization with increased left ventricular end-diastolic pressure from 0 to 30 mmHg were investigated using optical mapping in isolated perfused rabbit hearts. With respect to 0 mmHg, epicardial strain at 30 mmHg in the anterior left ventricle averaged 0.040 +/- 0.004 in the muscle fiber direction and 0.032 +/- 0.006 in the cross-fiber direction. An increase in ventricular loading increased average epicardial activation time by 25%+/- 3% (P < 0.0001) and correspondingly decreased average apparent surface conduction velocity by 16%+/- 7% (P = 0.007). Ventricular loading did not significantly alter action potential duration at 20% repolarization (APD20) but did at 80% repolarization (APD80), from 179 +/- 7 msec to 207 +/- 5 msec (P < 0.0001). The dispersion of APD20 was decreased with loading from 19 +/- 2 msec to 13 +/- 2 msec (P = 0.024), whereas the dispersion of APD80 was not significantly changed. These electrophysiologic changes with ventricular loading were not affected by the nonspecific stretch-activated channel blocker streptomycin (200 microM) and were not attributable to changes in myocardial perfusion or the presence of an electromechanical decoupling agent (butanedione monoxime) during optical mapping. CONCLUSION: Acute loading of the left ventricle of the isolated rabbit heart decreased apparent epicardial conduction velocity and increased action potential duration by a load-dependent mechanism that may not involve stretch-activated channels.

  9. Calcium influx inhibition: possible mechanism of the negative effect of tetrahydropalmatine on left ventricular pressure in isolated rat heart.

    PubMed

    Chan, P; Chiu, W T; Chen, Y J; Wu, P J; Cheng, J T

    1999-05-01

    The active ingredient dl-tetrahydropalmatine (THP) isolated from the traditional Chinese herb Corydalis racemosa has been found to have antihypertensive effects. However, severe cardiac and neurological toxic effects were reported from using this herb for the treatment of pain. In an isolated perfused rat heart model, THP at the concentration of 100 microM was found to have a negative effect (-45%) on left ventricular pressure and this effect was produced concentration-dependently from concentrations lower than 50 microM. In isolated cardiomyocytes, radioactive calcium influx was also inhibited significantly by THP at the concentration of 100 microM and this effect was also in a concentration-dependent manner (-39%). In a patient with latent heart disease, the use of Corydalis should probably be detrimental, the toxic effect was probably due to calcium influx inhibition.

  10. Heat production of quiescent ventricular trabeculae isolated from guinea-pig heart.

    PubMed Central

    Daut, J; Elzinga, G

    1988-01-01

    1. A new calorimetric technique has been developed which allows continuous measurement of the rate of energy expenditure in superfused preparations of cardiac muscle. Thin trabeculae of guinea-pig ventricular muscle were mounted in a Perspex tube of 0.8 mm inner diameter and the temperature difference of the perfusate upstream and downstream of the preparation was measured. 2. The resting heat rate of trabeculae of 240-575 microns diameter from guinea-pig heart was determined repeatedly for up to 6 h after cardiectomy. It did not vary with time during the course of the experiment. 3. The average resting heat rate measured in HEPES-buffered Tyrode solution containing 20 mM-glucose and 2 mM-pyruvate as substrates was 130 +/- 29 mW/g dry weight or 36 +/- 8 mW/cm3 of tissue (n = 15). This is an order of magnitude larger than the resting heat rate reported in the literature for isolated cardiac preparations. 4. After omitting the pyruvate from the superfusate the resting heat rate decreased to 60-70% of its steady value within 4 min. After readmission of pyruvate this effect was reversed. The average resting heat rate with glucose as sole substrate was 23 +/- 4 mW/cm3. 5. Uncoupling of the mitochondria by 50 microM-2,4-dinitrophenol (DNP) increased the heat rate up to 170 mW/cm3. This effect could be maintained for several minutes and was fully reversible. Raising the external K+ concentration to 150 mM (NaCl replaced by KCl) induced a transient rise in the rate of heat production up to 115 mW/cm3. 6. The heat production during uncoupling of the mitochondria and during potassium contractures was inversely related to the diameter of the preparation. Calculation based on Hill's equation (Hill, 1928) indicated that this was caused by the development of anoxia at the core of the preparation. 7. In contrast, the rate of heat production of quiescent preparations was not correlated with diameter and calculation indicated that at rest there was no anoxic core. The high value of

  11. A high-resolution thermoelectric module-based calorimeter for measuring the energetics of isolated ventricular trabeculae at body temperature.

    PubMed

    Johnston, Callum M; Han, June-Chiew; Ruddy, Bryan P; Nielsen, Poul M F; Taberner, Andrew J

    2015-07-15

    Isolated ventricular trabeculae are the most common experimental preparations used in the study of cardiac energetics. However, the experiments have been conducted at subphysiological temperatures. We have overcome this limitation by designing and constructing a novel calorimeter with sufficiently high thermal resolution for simultaneously measuring the heat output and force production of isolated, contracting, ventricular trabeculae at body temperature. This development was largely motivated by the need to better understand cardiac energetics by performing such measurements at body temperature to relate tissue performance to whole heart behavior in vivo. Our approach uses solid-state thermoelectric modules, tailored for both temperature sensing and temperature control. The thermoelectric modules have high sensitivity and low noise, which, when coupled with a multilevel temperature control system, enable an exceptionally high temperature resolution with a noise-equivalent power an order of magnitude greater than those of other existing muscle calorimeters. Our system allows us to rapidly and easily change the experimental temperature without disturbing the state of the muscle. Our calorimeter is useful in many experiments that explore the energetics of normal physiology as well as pathophysiology of cardiac muscle.

  12. [Left-ventricular function and physical exertion tolerance in patients with myocardial infarction with isolated lesion of the coronary arteries].

    PubMed

    Golikov, A P; Levshunov, S P; Belozerov, G E

    1989-01-01

    Myocardial infarction area and left-ventricular myocardial contractility, determined by sectoral scanning, and exercise tolerance were assessed in 47 myocardial infarction patients with isolated coronary arterial lesions. The area under myocardial infarction was shown to be dependent on the site of the atherosclerotic process rather than the degree of stenosis in patients with isolated coronary arterial lesions. A relationship was established between the incidence of complications developing in the acute phase of infarction and the degree of stenosis. The disease was complicated more frequently in patients with coronary arterial occlusion as compared to those with severe coronary-arterial stenosis. High stress tolerance, irrespective of the site of myocardial infarction, is an evidence of great functional potentials in this category of patients.

  13. [Isolated left ventricular muscular diverticulum in an adult. Value of non-invasive examinations].

    PubMed

    Holeman, A; Bellorini, M; Lefevre, T; Lévy, M; Loiret, J; Huerta, F; Thébault, B; Funck, F

    1997-10-01

    The authors report a case of ventriculum in a 45 year old women investigated for chest pain. This was a congenital muscular left ventricular diverticulum confirmed by a complete imaging series including echocardiography, magnetic resonance imaging, angio-scintigraphy and conventional angiography. This diverticulum was unusual due to the fact that there was no associated congenital disease and that it was discovered in an adult. The authors review the literature and discuss the value of non-invasive imaging procedures.

  14. Prolonged asystole in a patient with an isolated left ventricular assist device.

    PubMed

    Javed, Wasim; Chaggar, Parminder S; Venkateswaran, Rajamiyer; Shaw, Steven M

    2016-09-01

    Left ventricular assist devices (LVADs) are well established in the management of end-stage heart failure as either destination therapy, a bridge prior to cardiac transplantation or during myocardial recovery. Despite LVADs requiring adequate left ventricular preload to effectively augment systemic circulation, there have been rare cases of patients with LVADs surviving sustained, normally fatal arrhythmias, such as ventricular fibrillation and asystole. Whilst current reports describe an LVAD patient surviving 15 days with such an arrhythmia, we describe the case of a patient with an LVAD surviving 104 days of asystole via a Fontan mechanism of circulation, which we believe is the longest known survival of a sustained fatal arrhythmia. This case highlights the physiology of circulations supported by LVADs and the unique challenges that may arise in managing ambulant LVAD patients, such as predicting prognosis. Given the increasing use of LVADs to treat end-stage heart failure, these issues are likely to become more frequently encountered in the future. PMID:27539188

  15. The hypertrabeculated (noncompacted) left ventricle is different from the ventricle of embryos and ectothermic vertebrates.

    PubMed

    Jensen, Bjarke; Agger, Peter; de Boer, Bouke A; Oostra, Roelof-Jan; Pedersen, Michael; van der Wal, Allard C; Nils Planken, R; Moorman, Antoon F M

    2016-07-01

    Ventricular hypertrabeculation (noncompaction) is a poorly characterized condition associated with heart failure. The condition is widely assumed to be the retention of the trabeculated ventricular design of the embryo and ectothermic (cold-blooded) vertebrates. This assumption appears simplistic and counterfactual. Here, we measured a set of anatomical parameters in hypertrabeculation in man and in the ventricles of embryos and animals. We compared humans with left ventricular hypertrabeculation (N=21) with humans with structurally normal left ventricles (N=54). We measured ejection fraction and ventricular trabeculation using cardiovascular MRI. Ventricular trabeculation was further measured in series of embryonic human and 9 animal species, and in hearts of 15 adult animal species using MRI, CT, or histology. In human, hypertrabeculated left ventricles were significantly different from structurally normal left ventricles by all structural measures and ejection fraction. They were far less trabeculated than human embryonic hearts (15-40% trabeculated volume versus 55-80%). Early in development all vertebrate embryos acquired a ventricle with approximately 80% trabeculations, but only ectotherms retained the 80% trabeculation throughout development. Endothermic (warm-blooded) animals including human slowly matured in fetal and postnatal stages towards ventricles with little trabeculations, generally less than 30%. Further, the trabeculations of all embryos and adult ectotherms were very thin, less than 50 μm wide, whereas the trabeculations in adult endotherms and in the setting of hypertrabeculation were wider by orders of magnitude. It is concluded in contrast to a prevailing assumption, the hypertrabeculated left ventricle is not like the ventricle of the embryo or of adult ectotherms. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes

  16. The hypertrabeculated (noncompacted) left ventricle is different from the ventricle of embryos and ectothermic vertebrates.

    PubMed

    Jensen, Bjarke; Agger, Peter; de Boer, Bouke A; Oostra, Roelof-Jan; Pedersen, Michael; van der Wal, Allard C; Nils Planken, R; Moorman, Antoon F M

    2016-07-01

    Ventricular hypertrabeculation (noncompaction) is a poorly characterized condition associated with heart failure. The condition is widely assumed to be the retention of the trabeculated ventricular design of the embryo and ectothermic (cold-blooded) vertebrates. This assumption appears simplistic and counterfactual. Here, we measured a set of anatomical parameters in hypertrabeculation in man and in the ventricles of embryos and animals. We compared humans with left ventricular hypertrabeculation (N=21) with humans with structurally normal left ventricles (N=54). We measured ejection fraction and ventricular trabeculation using cardiovascular MRI. Ventricular trabeculation was further measured in series of embryonic human and 9 animal species, and in hearts of 15 adult animal species using MRI, CT, or histology. In human, hypertrabeculated left ventricles were significantly different from structurally normal left ventricles by all structural measures and ejection fraction. They were far less trabeculated than human embryonic hearts (15-40% trabeculated volume versus 55-80%). Early in development all vertebrate embryos acquired a ventricle with approximately 80% trabeculations, but only ectotherms retained the 80% trabeculation throughout development. Endothermic (warm-blooded) animals including human slowly matured in fetal and postnatal stages towards ventricles with little trabeculations, generally less than 30%. Further, the trabeculations of all embryos and adult ectotherms were very thin, less than 50 μm wide, whereas the trabeculations in adult endotherms and in the setting of hypertrabeculation were wider by orders of magnitude. It is concluded in contrast to a prevailing assumption, the hypertrabeculated left ventricle is not like the ventricle of the embryo or of adult ectotherms. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes

  17. Unidirectional block between isolated rabbit ventricular cells coupled by a variable resistance.

    PubMed Central

    Joyner, R W; Sugiura, H; Tan, R C

    1991-01-01

    We have used pairs of electrically coupled cardiac cells to investigate the dependence of successful conduction of an action potential on three components of the conduction process: (a) the amount of depolarization required to be produced in the nonstimulated cell (the "sink" for current flow) to initiate an action potential in the nonstimulated cell, (b) the intercellular resistance as the path for intercellular current flow, and (c) the ability of the stimulated cell to maintain a high membrane potential to serve as the "source" of current during the conduction process. We present data from eight pairs of simultaneously recorded rabbit ventricular cells, with the two cells of each pair physically separated from each other. We used an electronic circuit to pass currents into and out of each cell such that these currents produced the effects of any desired level of intercellular resistance. The cells of equal size (as assessed by their current threshold and their input resistance for small depolarizations) show bidirectional failure of conduction at very high values of intercellular resistance which then converts to successful bidirectional conduction at lower values of intercellular resistance. For cell pairs with asymmetrical cell sizes, there is a large range of values of intercellular resistance over which unidirectional block occurs with conduction successful from the larger cell to the smaller cell but with conduction block from the smaller cell to the larger cell. We then further show that one important component which limits the conduction process is the large early repolarization which occurs in the stimulated cell during the process of conduction, a process that we term "source loading." PMID:1760503

  18. Characterization and agonist regulation of muscarinic ([3H]N-methyl scopolamine) receptors in isolated ventricular myocytes from rat.

    PubMed

    Horackova, M; Robinson, B; Wilkinson, M

    1990-11-01

    Cell surface muscarinic cholinergic receptors have been characterized and quantified for the first time, in intact, isolated adult rat cardiomyocytes. The cells were previously established as functionally fully compatible with cellular responses in intact cardiac tissue. The specific binding of the hydrophilic radioligand, [3H]-NMS, (N-methyl-[3H]-scopolamine methylchloride) was found to be stereo-specific, saturable, reversible and of high affinity. Binding of [3H]-NMS demonstrated appropriate drug specificity and was positively correlated with increasing cell concentrations. Bmax for [3H]-NMS binding to ventricular myocytes, enzymatically dissociated from adult male rats, was 15.8 +/- 1.03 fmol/25 x 10(3) cells (at 4 degrees C) and KD was 0.27 +/- 0.05 nM (n = 14). Binding assays performed at a higher incubation temperature (30 degrees C) yielded a higher Bmax value (22.1 +/- 1.6 fmol/25 x 10(3) cells; n = 11; P less than 0.005 vs. Bmax at 4 degrees C) but an unchanged KD (0.23 +/- 0.06 nM). Pretreatment of myocytes with the muscarinic agonist carbachol (1 mM) at 37 degrees C resulted in a reduction (down-regulation) in specific binding of the hydrophilic ligand [3H]-NMS. The magnitude of this reduction and its rate of recovery were dependent on the time of the exposure to carbachol. Exposures of 30-60 min elicited down-regulated by 35% (Bmax = 14.29 +/- 1.66 changed to 9.5 +/- 1.79 fmol/25 x 10(3) cells, without change in KD P less than 0.01, n = 4). The down-regulation of the muscarinic receptors by carbachol was insensitive to application of bacitracin - an inhibitor of endocytosis. On the other hand preincubation with 10(-9)M atropine, a muscarinic antagonist, hindered the agonist-induced receptor "loss" from the cell surface confirming the muscarinic nature of these receptors. We conclude that our preparation of intact, isolated ventricular cardiomyocytes is ideally suited for the study of cell surface muscarinic receptor regulation under physiological and

  19. Characterization and agonist regulation of muscarinic ([3H]N-methyl scopolamine) receptors in isolated ventricular myocytes from rat.

    PubMed

    Horackova, M; Robinson, B; Wilkinson, M

    1990-11-01

    Cell surface muscarinic cholinergic receptors have been characterized and quantified for the first time, in intact, isolated adult rat cardiomyocytes. The cells were previously established as functionally fully compatible with cellular responses in intact cardiac tissue. The specific binding of the hydrophilic radioligand, [3H]-NMS, (N-methyl-[3H]-scopolamine methylchloride) was found to be stereo-specific, saturable, reversible and of high affinity. Binding of [3H]-NMS demonstrated appropriate drug specificity and was positively correlated with increasing cell concentrations. Bmax for [3H]-NMS binding to ventricular myocytes, enzymatically dissociated from adult male rats, was 15.8 +/- 1.03 fmol/25 x 10(3) cells (at 4 degrees C) and KD was 0.27 +/- 0.05 nM (n = 14). Binding assays performed at a higher incubation temperature (30 degrees C) yielded a higher Bmax value (22.1 +/- 1.6 fmol/25 x 10(3) cells; n = 11; P less than 0.005 vs. Bmax at 4 degrees C) but an unchanged KD (0.23 +/- 0.06 nM). Pretreatment of myocytes with the muscarinic agonist carbachol (1 mM) at 37 degrees C resulted in a reduction (down-regulation) in specific binding of the hydrophilic ligand [3H]-NMS. The magnitude of this reduction and its rate of recovery were dependent on the time of the exposure to carbachol. Exposures of 30-60 min elicited down-regulated by 35% (Bmax = 14.29 +/- 1.66 changed to 9.5 +/- 1.79 fmol/25 x 10(3) cells, without change in KD P less than 0.01, n = 4). The down-regulation of the muscarinic receptors by carbachol was insensitive to application of bacitracin - an inhibitor of endocytosis. On the other hand preincubation with 10(-9)M atropine, a muscarinic antagonist, hindered the agonist-induced receptor "loss" from the cell surface confirming the muscarinic nature of these receptors. We conclude that our preparation of intact, isolated ventricular cardiomyocytes is ideally suited for the study of cell surface muscarinic receptor regulation under physiological and

  20. Electrical and mechanical effects of new aminosteroids on guinea-pig isolated ventricular muscle.

    PubMed Central

    Adamantidis, M. M.; Honoré, E. R.; Dupuis, B. A.

    1988-01-01

    1. LND 623 and LND 796 are two aminosteroid derivatives which exert similar positive inotropic effects to digitalis. Their electrophysiological, toxic and inotropic effects were investigated in both normal and partially K+-depolarized ventricular muscle. 2. In guinea-pig myocardial fibres, LND 623 and LND 796 required tenfold higher concentrations than digoxin to induce the same signs of toxicity; e.g. triggered activities generated from delayed afterdepolarizations, leading to the marked depression of action potential characteristics and inexcitability. These abnormal rhythms and delayed afterdepolarizations were abolished by 1 mM caffeine. The toxic effects were reversed by washout, particularly in the case of LND 796. 3. In normal-K+ solution, LND 623 and LND 796 exhibited concentration-dependent positive inotropic effects on guinea-pig papillary muscle and increased concomitantly resting membrane potential and action potential amplitude. The range of active concentrations (0.1 to 1 microM) of LND 623 was larger than that of digoxin (0.3 to 1 microM). Like digoxin, LND 796 exerted negative inotropic effects at the lowest concentrations (0.01 to 0.03 microM) and positive inotropic effects at high concentrations (1 and 3 microM). 4. In partially K+-depolarized papillary muscle, in the presence of 2 microM histamine, LND 623 (3 and 10 microM) and LND 796 (10 and 30 microM) enhanced the two components P1 and P2 of the contraction and increased slow action potential amplitude, resting potential and maximal rate of depolarization. Low concentrations (0.03 to 0.3 microM) of LND 796 induced negative inotropic effects. beta-Adrenoceptor blockade with atenolol (1 microM) did not modify the activity of LND 623 but significantly enhanced the negative inotropic effect on P2 induced by 1 and 3 microM LND 796 and reduced the positive inotropic effect on P1 and P2 of the highest concentration (30 microM) studied. 5. In the presence of either caffeine (1 mM) or Ca2+-free, Sr2

  1. Right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle and ventricular septal defect

    PubMed Central

    Mangukia, Chirantan; Sethi, Sonali; Agarwal, Saket; Mishra, Smita; Satsangi, Deepak kumar

    2014-01-01

    Herein, we report an unusual case of right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle with ventricular septal defect. The blood supply to the innominate artery was by a collateral arising from the descending aorta. The embryological development of this anomaly can be explained by the hypothetical double aortic arch model proposed by Edwards with interruption of the arch at two levels. PMID:24987265

  2. [Relations of the duration of pre-existing angina pectoris, collateral circulation and left ventricular function after isolated coronary occlusion with or without myocardial infarction].

    PubMed

    Juillière, Y; Danchin, N; Grentzinger, A; Suty-Selton, C; Perrin, O; Guenoun, P; Pernot, C; Cherrier, F

    1990-10-01

    The aim of this retrospective study was to determine the relationship between the duration of preceding angina pectoris, collateral circulation and left ventricular function after isolated coronary occlusion with or without myocardial infarction. Coronary angiography of 138 consecutive patients showed isolated and complete occlusions of the left anterior descending (58 patients) or right coronary artery (80 patients). One hundred and four patients had myocardial infarction with (Group A, n = 21) or without (Group B, n = 83) preceding angina pectoris and 34 had angina without myocardial infarction (Group C). The left ventricular ejection fraction was measured by ventriculography in the 30 degrees right anterior oblique projection. The collateral circulation was assessed by coronary angiography and evaluated as follows: no flow or flow limited to collateral branches (subgroup 1) and partial or complete filling of the epicardial arterial segment (subgroup 2). In the global population the left ventricular ejection fraction was higher and the duration of preceding angina pectoris was longer in the subgroups with a well developed collateral circulation. There was no difference in ejection fraction between Groups A and B (presence of myocardial infarction), on the other hand, within each of the groups, a good collateral circulation (subgroup 2) was associated with a significantly higher ejection fraction. Group C (without infarction) patients had better ejection fractions than Groups A or B, especially when the collateral circulation was poorly developed. Within Group C, the quality of the collateral circulation did not seem to affect the ejection fraction. The left ventricular ejection fraction is lower in patients with isolated coronary occlusion and myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Acute reversal of phospholamban inhibition facilitates the rhythmic whole-cell propagating calcium waves in isolated ventricular myocytes.

    PubMed

    Chan, Yi-Hsin; Tsai, Wei-Chung; Song, Zhen; Ko, Christopher Y; Qu, Zhilin; Weiss, James N; Lin, Shien-Fong; Chen, Peng-Sheng; Jones, Larry R; Chen, Zhenhui

    2015-03-01

    Phospholamban (PLB) inhibits the activity of cardiac sarcoplasmic reticulum (SR) Ca(2+)-ATPase (SERCA2a). Phosphorylation of PLB during sympathetic activation reverses SERCA2a inhibition, increasing SR Ca(2+) uptake. However, sympathetic activation also modulates multiple other intracellular targets in ventricular myocytes (VMs), making it impossible to determine the specific effects of the reversal of PLB inhibition on the spontaneous SR Ca(2+) release. Therefore, it remains unclear how PLB regulates rhythmic activity in VMs. Here, we used the Fab fragment of 2D12, a monoclonal anti-PLB antibody, to test how acute reversal of PLB inhibition affects the spontaneous SR Ca(2+) release in normal VMs. Ca(2+) sparks and spontaneous Ca(2+) waves (SCWs) were recorded in the line-scan mode of confocal microscopy using the Ca(2+) fluorescent dye Fluo-4 in isolated permeabilized mouse VMs. Fab, which reverses PLB inhibition, significantly increased the frequency, amplitude, and spatial/temporal spread of Ca(2+) sparks in VMs exposed to 50 nM free [Ca(2+)]. At physiological diastolic free [Ca(2+)] (100-200 nM), Fab facilitated the formation of whole-cell propagating SCWs. At higher free [Ca(2+)], Fab increased the frequency and velocity, but decreased the decay time of the SCWs. cAMP had little additional effect on the frequency or morphology of Ca(2+) sparks or SCWs after Fab addition. These findings were complemented by computer simulations. In conclusion, acute reversal of PLB inhibition alone significantly increased the spontaneous SR Ca(2+) release, leading to the facilitation and organization of whole-cell propagating SCWs in normal VMs. PLB thus plays a key role in subcellular Ca(2+) dynamics and rhythmic activity of VMs.

  4. Ventricular assist device

    MedlinePlus

    VAD; RVAD; LVAD; BVAD; Right ventricular assist device; Left ventricular assist device; Biventricular assist device; Heart pump; Left ventricular assist system; LVAS; Implantable ventricular assist device

  5. Role of left ventricular twist mechanics in cardiomyopathies, dance of the helices

    PubMed Central

    Kauer, Floris; Geleijnse, Marcel Leonard; van Dalen, Bastiaan Martijn

    2015-01-01

    Left ventricular twist is an essential part of left ventricular function. Nevertheless, knowledge is limited in “the cardiology community” as it comes to twist mechanics. Fortunately the development of speckle tracking echocardiography, allowing accurate, reproducible and rapid bedside assessment of left ventricular twist, has boosted the interest in this important mechanical aspect of left ventricular deformation. Although the fundamental physiological role of left ventricular twist is undisputable, the clinical relevance of assessment of left ventricular twist in cardiomyopathies still needs to be established. The fact remains; analysis of left ventricular twist mechanics has already provided substantial pathophysiological understanding on a comprehensive variety of cardiomyopathies. It has become clear that increased left ventricular twist in for example hypertrophic cardiomyopathy may be an early sign of subendocardial (microvascular) dysfunction. Furthermore, decreased left ventricular twist may be caused by left ventricular dilatation or an extensive myocardial scar. Finally, the detection of left ventricular rigid body rotation in noncompaction cardiomyopathy may provide an indispensible method to objectively confirm this difficult diagnosis. All this endorses the value of left ventricular twist in the field of cardiomyopathies and may further encourage the implementation of left ventricular twist parameters in the “diagnostic toolbox” for cardiomyopathies. PMID:26322187

  6. Effects of bepridil on ventricular depolarization and repolarization of rabbit isolated hearts with particular reference to its possible proarrhythmic properties.

    PubMed Central

    Osaka, T.; Kodama, I.; Toyama, J.; Yamada, K.

    1988-01-01

    1. Effects of bepridil on ventricular depolarization and repolarization sequences were examined in rabbit Langendorff-perfused hearts. 2. In distant bipolar electrograms (DBEs), bepridil, 10(-6) M, caused a significant prolongation of QT intervals. At 10(-5) M, the QT prolongation was further enhanced, and a significant prolongation of QRS duration was also observed. Polymorphous ventricular tachycardia was frequently induced by a single premature stimulus at the higher concentration. 3. In epicardial electrograms recorded through modified bipolar electrodes, bepridil, 10(-6) M, prolonged the interval from the peak negative deflection of the QRS complex to the apex of the T wave (Q-aT), which corresponded to the intracellular action potential duration at 90% repolarization (APD90). The Q-aT prolongation was larger in the base than in the apex, resulting in a marked distortion and dispersion of repolarization. The epicardial activation sequence was unaffected. 4. At 10(-5) M bepridil, the dispersion of repolarization was much more enhanced by activation delay in the epicardial surface. 5. These findings suggest that bepridil causes regionally different lengthening of APD in ventricular muscle leading to an increase in temporal dispersion of repolarization, and that this dispersion may be inducive for re-entrant arrhythmias when accompanied by slow conduction at toxic doses. PMID:3260528

  7. Ventricular arrhythmias.

    PubMed Central

    Kavanagh, K M; Wyse, D G

    1988-01-01

    Sudden cardiac death claims thousands of Canadians annually. Ventricular tachycardia and fibrillation account for up to 85% of these deaths. Identifying the patients at risk remains a major challenge. Those who have recurrent ventricular tachycardia or have been resuscitated from ventricular fibrillation are generally considered to be at highest risk. Although ventricular premature beats in the absence of previous ventricular tachycardia or fibrillation are not helpful in identifying such patients in most cases, they can indicate increased risk for sudden cardiac death in the presence of a structural cardiac abnormality, particularly recent myocardial infarction; however, the need for treatment in such cases is speculative and is being investigated. Treatment is mandatory for survivors of an episode of ventricular fibrillation and those with recurrent sustained ventricular tachycardia or torsade de pointes ventricular tachycardia. The approach to management is either invasive or noninvasive. Selection of an antiarrhythmic agent is facilitated by knowledge of some basic electrophysiologic features of the heart and of the classification of antiarrhythmic drugs. However, drug therapy has to be individualized on the basis of efficacy, left ventricular function and adverse effects or potential adverse effects of the drug. Amiodarone therapy or nonpharmacologic therapy should be considered if a suitable antiarrhythmic agent cannot be found. PMID:3284626

  8. Closure of aorto-right ventricular tunnel with Amplatzer duct occluder II.

    PubMed

    Vijayalakshmi, I B; Narasimhan, Chitra; Agarwal, Ashish

    2013-04-01

    Aorto-right ventricular tunnel (ARVT) is a very rare, congenital, abnormal extracardiac channel that connects the ascending aorta at or above the sinotubular junction to the cavity of the right ventricle. Only 16 cases have been reported thus far in the English literature. We report the first transcatheter closure of ARVT with the Amplatzer duct occluder II in an infant, with both coronary arteries arising from the left coronary sinus and with biventricular apical non-compaction.

  9. Closure of aorto-right ventricular tunnel with Amplatzer duct occluder II.

    PubMed

    Vijayalakshmi, I B; Narasimhan, Chitra; Agarwal, Ashish

    2013-04-01

    Aorto-right ventricular tunnel (ARVT) is a very rare, congenital, abnormal extracardiac channel that connects the ascending aorta at or above the sinotubular junction to the cavity of the right ventricle. Only 16 cases have been reported thus far in the English literature. We report the first transcatheter closure of ARVT with the Amplatzer duct occluder II in an infant, with both coronary arteries arising from the left coronary sinus and with biventricular apical non-compaction. PMID:23549501

  10. Aeroacoustic theory for noncompact wing-gust interaction

    NASA Technical Reports Server (NTRS)

    Martinez, R.; Widnall, S. E.

    1981-01-01

    Three aeroacoustic models for noncompact wing-gust interaction were developed for subsonic flow. The first is that for a two dimensional (infinite span) wing passing through an oblique gust. The unsteady pressure field was obtained by the Wiener-Hopf technique; the airfoil loading and the associated acoustic field were calculated, respectively, by allowing the field point down on the airfoil surface, or by letting it go to infinity. The second model is a simple spanwise superposition of two dimensional solutions to account for three dimensional acoustic effects of wing rotation (for a helicopter blade, or some other rotating planform) and of finiteness of wing span. A three dimensional theory for a single gust was applied to calculate the acoustic signature in closed form due to blade vortex interaction in helicopters. The third model is that of a quarter infinite plate with side edge through a gust at high subsonic speed. An approximate solution for the three dimensional loading and the associated three dimensional acoustic field in closed form was obtained. The results reflected the acoustic effect of satisfying the correct loading condition at the side edge.

  11. Wilson loops in noncompact U(1) gauge theories at criticality

    SciTech Connect

    Metlitski, Max A.

    2008-04-15

    We study the properties of Wilson loops in three-dimensional noncompact U(1) gauge theories with global Abelian symmetries. We use duality in the continuum and on the lattice to argue that, close to the critical point between the Higgs and Coulomb phases, all correlators of the Wilson loops are periodic functions of the Wilson loop charge, Q. The period depends on the global symmetry of the theory, which determines the magnetic flux carried by the dual particles. For single flavor scalar electrodynamics, the emergent period is Q=1. In the general case of N complex scalars with a U(1){sup N-1} global symmetry, the period is Q=N. We also give some arguments why this phenomenon does not generalize to theories with a full non-Abelian SU(N) symmetry, where no periodicity in Q is expected. Implications for lattice simulations, as well as for physical systems, such as easy-plane antiferromagnets and disordered superfluids, are noted.

  12. On a Mathematical Model with Noncompact Boundary Conditions Describing Bacterial Population

    NASA Astrophysics Data System (ADS)

    Boulanouar, Mohamed

    2013-04-01

    In this work, we are concerned with the well-posedness of a mathematical model describing a maturation-velocity structured bacterial population. Each bacterium is distinguished by its degree of maturity and its maturation velocity. The bacterial mitosis is mathematically described by noncompact boundary conditions. We show that the mathematical model is governed by a positive strongly continuous semigroup.

  13. Contribution of sarcolemmal sodium-calcium exchange and intracellular calcium release to force development in isolated canine ventricular muscle

    PubMed Central

    1992-01-01

    The aim of this work was to determine the relationship between peak twitch amplitude and sarcoplasmic reticulum (SR) Ca2+ content during changes of stimulation frequency in isolated canine ventricle, and to estimate the extent to which these changes were dependent upon sarcolemmal Na(+)-Ca2+ exchange. In physiological [Na+]o, increased stimulation frequency in the 0.2-2-Hz range resulted in a positive inotropic effect characterized by an increase in peak twitch amplitude and a decrease in the duration of contraction, measured as changes in isometric force development or unloaded cell shortening in intact muscle and isolated single cells, respectively. Action potentials recorded from single cells indicated that the inotropic effect was associated with a progressive decrease of action potential duration and a marked reduction in average time spent by the cell near the resting potential during the stimulus train. The frequency-dependent increase of peak twitch force was correlated with an increase of Ca2+ uptake into and release from the SR. This was estimated indirectly using the phasic contractile response to rapid (less than 1 s) lowering of perfusate temperature from 37 degrees C to 0-2 degrees C and changes of twitch amplitude resulting from perturbations in the pattern of electrical stimulation. Lowering [Na+]o from 140 to 70 mM resulted in an increase of contractile strength, which was accompanied by a similar increase of apparent SR Ca2+ content, both of which could be abolished by exposure to ryanodine (1 x 10(-8) M), caffeine (3 x 10(-3) M), or nifedipine (2 x 10(-6) M). Increased stimulation frequency in 70 mM [Na+]o resulted in a negative contractile staircase, characterized by a graded decrease of peak isometric force development or unloaded cell shortening. SR Ca2+ content estimated under identical conditions remained unaltered. Rate constants derived from mechanical restitution studies implied that the depressant effect of increased stimulation

  14. Effects of salicylic acid on post-ischaemic ventricular function and purine efflux in isolated mouse hearts.

    PubMed

    Farthing, Don; Gehr, Lynne; Karnes, H Thomas; Sica, Domenic; Gehr, Todd; Larus, Terri; Farthing, Christine; Xi, Lei

    2007-01-01

    Acetyl salicylic acid (aspirin) is one of the most widely used drugs in the world. Various plasma concentrations of aspirin and its predominant metabolite, salicylic acid, are required for its antiarthritic (1.5-2.5 mM), anti-inflammatory (0.5-5.0 mM) or antiplatelet (0.18-0.36 mM) actions. A recent study demonstrated the inhibitory effects of both aspirin and salicylic acid on oxidative phosphorylation and ATP synthesis in isolated rat cardiac mitochondria in a dose-dependent manner (0-10 mM concentration range). In this context, the present study was conducted to determine the effects of salicylic acid on inosine efflux (a potential biomarker of acute cardiac ischaemia) as well as cardiac contractile function in the isolated mouse heart following 20 min of zero-flow global ischaemia. Inosine efflux was found at significantly higher concentrations in ischaemic hearts perfused with Krebs buffer fortified with 1.0 mM salicylic acid compared with those without salicylic acid (12575+/-3319 vs. 1437+/-348 ng ml(-1) min(-1), mean+/-SEM, n=6 per group, p<0.01). These results indicate that 1.0 mM salicylic acid potentiates 8.8-fold ATP nucleotide purine catabolism into its metabolites (e.g. inosine, hypoxanthine). Salicylic acid (0.1 or 1.0 mM) did not appreciably inhibit purine nucleoside phosphorylase (the enzyme converts inosine to hypoxanthine) suggesting the augmented inosine efflux was due to the salicylic acid effect on upstream elements of cellular respiration. Whereas post-ischaemic cardiac function was further depressed by 1.0 mM salicylic acid, perfusion with 0.1 mM salicylic acid led to a remarkable functional improvement despite moderately increased inosine efflux (2.7-fold). We conclude that inosine is a sensitive biomarker for detecting cardiac ischaemia and salicylic acid-induced effects on cellular respiration. However, the inosine efflux level appears to be a poor predictor of the individual post-ischaemic cardiac functional recovery in this ex vivo

  15. Effects of salicylic acid on post-ischaemic ventricular function and purine efflux in isolated mouse hearts.

    PubMed

    Farthing, Don; Gehr, Lynne; Karnes, H Thomas; Sica, Domenic; Gehr, Todd; Larus, Terri; Farthing, Christine; Xi, Lei

    2007-01-01

    Acetyl salicylic acid (aspirin) is one of the most widely used drugs in the world. Various plasma concentrations of aspirin and its predominant metabolite, salicylic acid, are required for its antiarthritic (1.5-2.5 mM), anti-inflammatory (0.5-5.0 mM) or antiplatelet (0.18-0.36 mM) actions. A recent study demonstrated the inhibitory effects of both aspirin and salicylic acid on oxidative phosphorylation and ATP synthesis in isolated rat cardiac mitochondria in a dose-dependent manner (0-10 mM concentration range). In this context, the present study was conducted to determine the effects of salicylic acid on inosine efflux (a potential biomarker of acute cardiac ischaemia) as well as cardiac contractile function in the isolated mouse heart following 20 min of zero-flow global ischaemia. Inosine efflux was found at significantly higher concentrations in ischaemic hearts perfused with Krebs buffer fortified with 1.0 mM salicylic acid compared with those without salicylic acid (12575+/-3319 vs. 1437+/-348 ng ml(-1) min(-1), mean+/-SEM, n=6 per group, p<0.01). These results indicate that 1.0 mM salicylic acid potentiates 8.8-fold ATP nucleotide purine catabolism into its metabolites (e.g. inosine, hypoxanthine). Salicylic acid (0.1 or 1.0 mM) did not appreciably inhibit purine nucleoside phosphorylase (the enzyme converts inosine to hypoxanthine) suggesting the augmented inosine efflux was due to the salicylic acid effect on upstream elements of cellular respiration. Whereas post-ischaemic cardiac function was further depressed by 1.0 mM salicylic acid, perfusion with 0.1 mM salicylic acid led to a remarkable functional improvement despite moderately increased inosine efflux (2.7-fold). We conclude that inosine is a sensitive biomarker for detecting cardiac ischaemia and salicylic acid-induced effects on cellular respiration. However, the inosine efflux level appears to be a poor predictor of the individual post-ischaemic cardiac functional recovery in this ex vivo

  16. The calcium-independent transient outward potassium current in isolated ferret right ventricular myocytes. I. Basic characterization and kinetic analysis

    PubMed Central

    1993-01-01

    Enzymatically isolated myocytes from ferret right ventricles (12-16 wk, male) were studied using the whole cell patch clamp technique. The macroscopic properties of a transient outward K+ current I(to) were quantified. I(to) is selective for K+, with a PNa/PK of 0.082. Activation of I(to) is a voltage-dependent process, with both activation and inactivation being independent of Na+ or Ca2+ influx. Steady-state inactivation is well described by a single Boltzmann relationship (V1/2 = -13.5 mV; k = 5.6 mV). Substantial inactivation can occur during a subthreshold depolarization without any measurable macroscopic current. Both development of and recovery from inactivation are well described by single exponential processes. Ensemble averages of single I(to) channel currents recorded in cell-attached patches reproduce macroscopic I(to) and indicate that inactivation is complete at depolarized potentials. The overall inactivation/recovery time constant curve has a bell-shaped potential dependence that peaks between -10 and -20 mV, with time constants (22 degrees C) ranging from 23 ms (-90 mV) to 304 ms (-10 mV). Steady-state activation displays a sigmoidal dependence on membrane potential, with a net aggregate half- activation potential of +22.5 mV. Activation kinetics (0 to +70 mV, 22 degrees C) are rapid, with I(to) peaking in approximately 5-15 ms at +50 mV. Experiments conducted at reduced temperatures (12 degrees C) demonstrate that activation occurs with a time delay. A nonlinear least- squares analysis indicates that three closed kinetic states are necessary and sufficient to model activation. Derived time constants of activation (22 degrees C) ranged from 10 ms (+10 mV) to 2 ms (+70 mV). Within the framework of Hodgkin-Huxley formalism, Ito gating can be described using an a3i formulation. PMID:8505627

  17. Effects of the Selective Stretch-Activated Channel Blocker GsMtx4 on Stretch-Induced Changes in Refractoriness in Isolated Rat Hearts and on Ventricular Premature Beats and Arrhythmias after Coronary Occlusion in Swine

    PubMed Central

    Barrabés, José A.; Inserte, Javier; Agulló, Luis; Rodríguez-Sinovas, Antonio; Alburquerque-Béjar, Juan J.; Garcia-Dorado, David

    2015-01-01

    Mechanical factors may contribute to ischemic ventricular arrhythmias. GsMtx4 peptide, a selective stretch-activated channel blocker, inhibits stretch-induced atrial arrhythmias. We aimed to assess whether GsMtx4 protects against ventricular ectopy and arrhythmias following coronary occlusion in swine. First, the effects of 170-nM GsMtx4 on the changes in the effective refractory period (ERP) induced by left ventricular (LV) dilatation were assessed in 8 isolated rat hearts. Then, 44 anesthetized, open-chest pigs subjected to 50-min left anterior descending artery occlusion and 2-h reperfusion were blindly allocated to GsMtx4 (57 μg/kg iv. bolus and 3.8 μg/kg/min infusion, calculated to attain the above concentration in plasma) or saline, starting 5-min before occlusion and continuing until after reflow. In rat hearts, LV distension induced progressive reductions in ERP (35±2, 32±2, and 29±2 ms at 0, 20, and 40 mmHg of LV end-diastolic pressure, respectively, P<0.001) that were prevented by GsMTx4 (33±2, 33±2, and 32±2 ms, respectively, P=0.002 for the interaction with LV end-diastolic pressure). Pigs receiving GsMtx4 had similar number of ventricular premature beats during the ischemic period as control pigs (110±28 vs. 103±21, respectively, P=0.842). There were not significant differences among treated and untreated animals in the incidence of ventricular fibrillation (13.6 vs. 22.7%, respectively, P=0.696) or tachycardia (36.4 vs. 50.0%, P=0.361) or in the number of ventricular tachycardia episodes during the occlusion period (1.8±0.7 vs. 5.5±2.6, P=0.323). Thus, GsMtx4 administered under these conditions does not suppress ventricular ectopy following coronary occlusion in swine. Whether it might protect against malignant arrhythmias should be tested in studies powered for these outcomes. PMID:25938516

  18. Arrhythmogenic Right Ventricular Dysplasia

    MedlinePlus

    MENU Return to Web version Arrhythmogenic Right Ventricular Dysplasia Overview What is arrhythmogenic right ventricular dysplasia? Arrhythmogenic right ventricular dysplasia (say: “uh-rith-mo-jen-ic right ven-trick- ...

  19. Inhibitory Effect of Cinobufagin on L-Type Ca2+ Currents, Contractility, and Ca2+ Homeostasis of Isolated Adult Rat Ventricular Myocytes

    PubMed Central

    Li, Pinya; Song, Qiongtao; Liu, Tao; Wu, Zhonglin; Chu, Xi; Zhang, Xuan; Zhang, Ying; Gao, Yonggang; Zhang, Jianping; Chu, Li

    2014-01-01

    Cinobufagin (CBG), a major bioactive ingredient of the bufanolide steroid compounds of Chan Su, has been widely used to treat coronary heart disease. At present, the effect of CBG on the L-type Ca2+ current (ICa-L) of ventricular myocytes remains undefined. The aim of the present study was to characterize the effect of CBG on intracellular Ca2+ ([Ca2+]i) handling and cell contractility in rat ventricular myocytes. CBG was investigated by determining its influence on ICa-L, Ca2+ transient, and contractility in rat ventricular myocytes using the whole-cell patch-clamp technique and video-based edge-detection and dual-excitation fluorescence photomultiplier systems. The dose of CBG (10−8 M) decreased the maximal inhibition of CBG by 47.93%. CBG reduced ICa-L in a concentration-dependent manner with an IC50 of 4 × 10−10 M, upshifted the current-voltage curve of ICa-L, and shifted the activation and inactivation curves of ICa-L leftward. Moreover, CBG diminished the amplitude of the cell shortening and Ca2+ transients with a decrease in the time to peak (Tp) and the time to 50% of the baseline (Tr). CBG inhibited L-type Ca2+ channels, and reduced [Ca2+]i and contractility in adult rat ventricular myocytes. These findings contribute to the understanding of the cardioprotective efficacy of CBG. PMID:24977199

  20. Ventricular septal defect (image)

    MedlinePlus

    Ventricular septal defect is a congenital defect of the heart, that occurs as an abnormal opening in ... wall that separates the right and left ventricles. Ventricular septal defect may also be associated with other ...

  1. Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis.

    PubMed

    Han, Peidong; Bloomekatz, Joshua; Ren, Jie; Zhang, Ruilin; Grinstein, Jonathan D; Zhao, Long; Burns, C Geoffrey; Burns, Caroline E; Anderson, Ryan M; Chi, Neil C

    2016-06-29

    Many organs are composed of complex tissue walls that are structurally organized to optimize organ function. In particular, the ventricular myocardial wall of the heart comprises an outer compact layer that concentrically encircles the ridge-like inner trabecular layer. Although disruption in the morphogenesis of this myocardial wall can lead to various forms of congenital heart disease and non-compaction cardiomyopathies, it remains unclear how embryonic cardiomyocytes assemble to form ventricular wall layers of appropriate spatial dimensions and myocardial mass. Here we use advanced genetic and imaging tools in zebrafish to reveal an interplay between myocardial Notch and Erbb2 signalling that directs the spatial allocation of myocardial cells to their proper morphological positions in the ventricular wall. Although previous studies have shown that endocardial Notch signalling non-cell-autonomously promotes myocardial trabeculation through Erbb2 and bone morphogenetic protein (BMP) signalling, we discover that distinct ventricular cardiomyocyte clusters exhibit myocardial Notch activity that cell-autonomously inhibits Erbb2 signalling and prevents cardiomyocyte sprouting and trabeculation. Myocardial-specific Notch inactivation leads to ventricles of reduced size and increased wall thickness because of excessive trabeculae, whereas widespread myocardial Notch activity results in ventricles of increased size with a single-cell-thick wall but no trabeculae. Notably, this myocardial Notch signalling is activated non-cell-autonomously by neighbouring Erbb2-activated cardiomyocytes that sprout and form nascent trabeculae. Thus, these findings support an interactive cellular feedback process that guides the assembly of cardiomyocytes to morphologically create the ventricular myocardial wall and more broadly provide insight into the cellular dynamics of how diverse cell lineages organize to create form.

  2. Coordinating cardiomyocyte interactions to direct ventricular chamber morphogenesis.

    PubMed

    Han, Peidong; Bloomekatz, Joshua; Ren, Jie; Zhang, Ruilin; Grinstein, Jonathan D; Zhao, Long; Burns, C Geoffrey; Burns, Caroline E; Anderson, Ryan M; Chi, Neil C

    2016-06-30

    Many organs are composed of complex tissue walls that are structurally organized to optimize organ function. In particular, the ventricular myocardial wall of the heart comprises an outer compact layer that concentrically encircles the ridge-like inner trabecular layer. Although disruption in the morphogenesis of this myocardial wall can lead to various forms of congenital heart disease and non-compaction cardiomyopathies, it remains unclear how embryonic cardiomyocytes assemble to form ventricular wall layers of appropriate spatial dimensions and myocardial mass. Here we use advanced genetic and imaging tools in zebrafish to reveal an interplay between myocardial Notch and Erbb2 signalling that directs the spatial allocation of myocardial cells to their proper morphological positions in the ventricular wall. Although previous studies have shown that endocardial Notch signalling non-cell-autonomously promotes myocardial trabeculation through Erbb2 and bone morphogenetic protein (BMP) signalling, we discover that distinct ventricular cardiomyocyte clusters exhibit myocardial Notch activity that cell-autonomously inhibits Erbb2 signalling and prevents cardiomyocyte sprouting and trabeculation. Myocardial-specific Notch inactivation leads to ventricles of reduced size and increased wall thickness because of excessive trabeculae, whereas widespread myocardial Notch activity results in ventricles of increased size with a single-cell-thick wall but no trabeculae. Notably, this myocardial Notch signalling is activated non-cell-autonomously by neighbouring Erbb2-activated cardiomyocytes that sprout and form nascent trabeculae. Thus, these findings support an interactive cellular feedback process that guides the assembly of cardiomyocytes to morphologically create the ventricular myocardial wall and more broadly provide insight into the cellular dynamics of how diverse cell lineages organize to create form. PMID:27357797

  3. QED{sub 3} on a space-time lattice: Compact versus noncompact formulation

    SciTech Connect

    Fiore, R.; Giudice, P.; Giuliano, D.; Marmottini, D.; Papa, A.; Sodano, P.

    2005-11-01

    We study quantum electrodynamics in a (2+1)-dimensional space-time with two flavors of dynamical fermions by numerical simulations on the lattice. We discretize the theory using both the compact and the noncompact formulations and analyze the behavior of the chiral condensate and of the monopole density in the finite lattice regime as well as in the continuum limit. By comparing the results obtained with the two approaches, we draw some conclusions about the possible equivalence of the two lattice formulations in the continuum limit.

  4. Spatiotemporal evolution of ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Witkowski, Francis X.; Leon, L. Joshua; Penkoske, Patricia A.; Giles, Wayne R.; Spano, Mark L.; Ditto, William L.; Winfree, Arthur T.

    1998-03-01

    Sudden cardiac death is the leading cause of death in the industrialized world, with the majority of such tragedies being due to ventricular fibrillation. Ventricular fibrillation is a frenzied and irregular disturbance of the heart rhythm that quickly renders the heart incapable of sustaining life. Rotors, electrophysiological structures that emit rotating spiral waves, occur in several systems that all share with the heart the functional properties of excitability and refractoriness. These re-entrant waves, seen in numerical solutions of simplified models of cardiac tissue, may occur during ventricular tachycardias,. It has been difficult to detect such forms of re-entry in fibrillating mammalian ventricles. Here we show that, in isolated perfused dog hearts, high spatial and temporal resolution mapping of optical transmembrane potentials can easily detect transiently erupting rotors during the early phase of ventricular fibrillation. This activity is characterized by a relatively high spatiotemporal cross-correlation. During this early fibrillatory interval, frequent wavefront collisions and wavebreak generation are also dominant features. Interestingly, this spatiotemporal pattern undergoes an evolution to a less highly spatially correlated mechanism that lacks the epicardial manifestations of rotors despite continued myocardial perfusion.

  5. Classification of Invariant Differential Operators for Non-Compact Lie Algebras via Parabolic Relations

    NASA Astrophysics Data System (ADS)

    Dobrev, V. K.

    2014-05-01

    In the present paper we review the progress of the project of classification and construction of invariant differential operators for non-compact semisimple Lie groups. Our starting points is the class of algebras, which we called earlier 'conformal Lie algebras' (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this we introduced recently the new notion of parabolic relation between two non-compact semisimple Lie algebras G and G' that have the same complexification and possess maximal parabolic subalgebras with the same complexification. Thus, we consider the exceptional algebra E7(7) which is parabolically related to the CLA E7(-25). Other interesting examples are the orthogonal algebras so(p, q) all of which are parabolically related to the conformal algebra so(n, 2) with p + q = n + 2, the parabolic subalgebras including the Lorentz subalgebra so(n - 1,1) and its analogs so(p - 1, q - 1). Further we consider the algebras sl(2n, Bbb R) and for n = 2k the algebras su* (4k) which are parabolically related to the CLA su(n,n). Further we consider the algebras sp(r,r) which are parabolically related to the CLA sp(2r, Bbb R). We consider also E6(6) and E6(2) which are parabolically related to the hermitian symmetric case E6(-14),

  6. A porcine model for acute ischaemic right ventricular dysfunction

    PubMed Central

    Haraldsen, Pernille; Lindstedt, Sandra; Metzsch, Carsten; Algotsson, Lars; Ingemansson, Richard

    2014-01-01

    OBJECTIVES To establish an experimental model for acute ischaemic isolated right ventricular dysfunction and the subsequent haemodynamic changes. METHODS An open-chest porcine model with ischaemic dysfunction of the right ventricle induced by ligation of the three main branches supporting the right ventricular free wall. Invasive monitoring of mean arterial blood pressure (MAP), central venous pressure (CVP), left atrial pressure (LAP) and right ventricular pressure (RVP); ultrasonic measurement of cardiac output (CO) and calculation of haemodynamic parameters such as stroke volume (SV), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and right ventricular stroke work (RVSW) using standard formulae. RESULTS The ischaemic challenge to the right ventricle resulted in a significant (≥30%) reduction in RVSW associated with an increase (6–25%) in CVP and reduction (8–18%) in pulmonary artery pressure (PAP) despite unchanged PVR, all reflecting the failing right ventricle. There was also a significant drop in CO (14–22%) despite unchanged LAP indicating lessened transpulmonary delivery of left ventricular preload due to the failing right ventricle causing the haemodynamic compromise rather than left ventricular failure. Supraventricular and ventricular arrhythmias occurred in three and two out of seven pigs, respectively—all of which except one were successfully resuscitated with cardioversion and/or defibrillation. CONCLUSIONS This novel open-chest porcine model of induced ischaemia of the right ventricular free wall resulted in significant haemodynamic compromise confirmed using standard haemodynamic measurements making it useful for further research on acute, ischaemic isolated right ventricular failure. PMID:24092465

  7. Percutaneous left ventricular restoration.

    PubMed

    Ige, Mobolaji; Al-Kindi, Sadeer G; Attizzani, Guilherme; Costa, Marco; Oliveira, Guilherme H

    2015-04-01

    The ventricular partitioning device known as Parachute is the first and only percutaneously implantable device aimed at restoration of normal left ventricular geometry in humans. Since its conception, this technology has undergone extensive animal and human testing, with proved feasibility and safety, and is currently being studied in a pivotal randomized clinical trial. This article discusses ventricular remodeling and therapies attempted in the past, details the components of the ventricular partitioning device, describes the implanting technique, and reviews the most current experience of this device in humans.

  8. Percutaneous left ventricular restoration.

    PubMed

    Ige, Mobolaji; Al-Kindi, Sadeer G; Attizzani, Guilherme; Costa, Marco; Oliveira, Guilherme H

    2015-04-01

    The ventricular partitioning device known as Parachute is the first and only percutaneously implantable device aimed at restoration of normal left ventricular geometry in humans. Since its conception, this technology has undergone extensive animal and human testing, with proved feasibility and safety, and is currently being studied in a pivotal randomized clinical trial. This article discusses ventricular remodeling and therapies attempted in the past, details the components of the ventricular partitioning device, describes the implanting technique, and reviews the most current experience of this device in humans. PMID:25834974

  9. Right ventricular mass estimation by angioechocardiography.

    PubMed

    Arcilla, R A; Mathew, R; Sodt, P; Lester, L; Cahill, N; Thilenius, O G

    1976-01-01

    A combined angiocardiographic-echocardiographic method for estimating right ventricular wall mass is described. Biplane cineangiocardiograms are analyzed for ventricular volume in end-diastole, and wall thickness is determined from echocardiograms obtained with a high frequency transducer and strip chart recorder, The intracavitary and the external surface volumes of the ventricle are derived, and the difference multiplied by 1.050, the specific gravity of myocardium. Excellent correlation was observed between right ventricular wall mass and body surface area in normal children (r = 0.93). The mean right ventricular mass was 44.5 g/M2 as compared to 78.1 g/M2 for the left ventricle, corresponding mass/EDV values were 0.48 g/cm3 and 1.26 g/cm3, respectively. In isolated right ventricular pressure overload, the increase in right ventricular mass is chiefly due to the increase in wall thickness; in volume overload, it is due mostly to the increase in chamber volume,

  10. The index theory on non-compact manifolds with proper group action

    NASA Astrophysics Data System (ADS)

    Braverman, Maxim

    2015-12-01

    We construct a regularized index of a generalized Dirac operator on a complete Riemannian manifold endowed with a proper action of a unimodular Lie group. We show that the index is preserved by a certain class of non-compact cobordisms and prove a gluing formula for the regularized index. The results of this paper generalize our previous construction of index for compact group action and the recent paper of Hochs and Mathai who studied the case of a Hamiltonian action on a symplectic manifold. As an application of the cobordism invariance of the index we give an affirmative answer to a question of Hochs and Mathai about the independence of the Hochs-Mathai quantization of the metric, connection and other choices.

  11. Noncompact lattice QED with two charges: Phase diagram and renormalization group flow

    SciTech Connect

    Ali Khan, A.

    1996-06-01

    The phase diagram of noncompact lattice QED in four dimensions with staggered fermions of charges 1 and {minus}1/2 is investigated. The renormalized charges are determined and found to be in agreement with perturbation theory. This is an indication that there is no continuum limit with nonvanishing renormalized gauge coupling, and that the theory has a validity bound for every finite value of the renormalized coupling. The renormalization group flow of the charges is investigated and an estimate for the validity bound as a function of the cutoff is obtained. Generalizing this estimate to all fermions in the standard model, it is found that a cutoff at the Planck scale implies that {alpha}{sub {ital R}} has to be less than 1/80. Because of spontaneous chiral symmetry breaking, strongly bound fermion-antifermion composite states are generated. Their spectrum is discussed. {copyright} {ital 1996 The American Physical Society.}

  12. Right ventricular failure after left ventricular assist device insertion: preoperative risk factors.

    PubMed

    Santambrogio, Luisa; Bianchi, Tiziana; Fuardo, Marinella; Gazzoli, Fabrizio; Veronesi, Roberto; Braschi, Antonio; Maurelli, Marco

    2006-08-01

    Right ventricular failure after left ventricular assist device placement is the major concern on weaning from cardiopulmonary bypass and it is one of the most serious complications in the postoperative period. This complication has a poor prognosis and is generally unpredictable. The identification of pre-operative risk factor for this serious complication is incomplete yet. In order to determine pre-operative risk for severe right ventricular failure after left ventricular assist device support we analyzed preoperative hemodynamics, laboratory data and characteristics of 48 patients who received Novacor (World Heart Corp., Ottawa, ON, Canada). We compared the data from the patients who developed right ventricular failure and the patients who did not. Right ventricular failure occurred in 16% of the patients. There was no significant difference between the groups in demographic characteristics. We identified as preoperative risk factors the pre-operative low mean pulmonary artery and the impairment of hepatic and renal function on laboratory data. Our results confirm in part the findings of the few previous studies. This information may be useful for the patient selection for isolated left ventricular assist device implantation, but other studies are necessary before establishing criteria for patient selection for univentricular support universally accepted.

  13. Ventricular tachycardia in acromegaly.

    PubMed

    Arias, Miguel A; Pachón, Marta; Rodríguez-Padial, Luis

    2011-02-01

    Cases of sudden cardiac death have been reported in patients with acromegaly. Malignant ventricular arrhythmias may play an important role in this fatal complication, but the exact mechanisms are not well understood. We report on an acromegalic patient presenting with documented recurrent syncopal ventricular tachycardia.

  14. Matrix models, 4D black holes and topological strings on non-compact Calabi-Yau manifolds

    NASA Astrophysics Data System (ADS)

    Danielsson, Ulf H.; Olsson, Martin E.; Vonk, Marcel

    2004-11-01

    We study the relation between c = 1 matrix models at self-dual radii and topological strings on non-compact Calabi-Yau manifolds. Particularly the special case of the deformed matrix model is investigated in detail. Using recent results on the equivalence of the partition function of topological strings and that of four dimensional BPS black holes, we are able to calculate the entropy of the black holes, using matrix models. In particular, we show how to deal with the divergences that arise as a result of the non-compactness of the Calabi-Yau. The main result is that the entropy of the black hole at zero temperature coincides with the canonical free energy of the matrix model, up to a proportionality constant given by the self-dual temperature of the matrix model.

  15. Quantum reference frames associated with noncompact groups: The case of translations and boosts and the role of mass

    NASA Astrophysics Data System (ADS)

    Smith, Alexander R. H.; Piani, Marco; Mann, Robert B.

    2016-07-01

    Quantum communication without a shared reference frame or the construction of a relational quantum theory requires the notion of a quantum reference frame. We analyze aspects of quantum reference frames associated with noncompact groups, specifically, the group of spatial translations and Galilean boosts. We begin by demonstrating how the usually employed group average, used to dispense of the notion of an external reference frame, leads to unphysical states when applied to reference frames associated with noncompact groups. However, we show that this average does lead naturally to a reduced state on the relative degrees of freedom of a system, which was previously considered by Angelo et al. [J. Phys. A: Math. Theor. 44, 145304 (2011), 10.1088/1751-8113/44/14/145304]. We then study in detail the informational properties of this reduced state for systems of two and three particles in Gaussian states.

  16. Vulnerability to ventricular fibrillation

    NASA Astrophysics Data System (ADS)

    Janse, Michiel J.

    1998-03-01

    One of the factors that favors the development of ventricular fibrillation is an increase in the dispersion of refractoriness. Experiments will be described in which an increase in dispersion in the recovery of excitability was determined during brief episodes of enhanced sympathetic nerve activity, known to increase the risk of fibrillation. Whereas in the normal heart ventricular fibrillation can be induced by a strong electrical shock, a premature stimulus of moderate intensity only induces fibrillation in the presence of regional ischemia, which greatly increases the dispersion of refractoriness. One factor that is of importance for the transition of reentrant ventricular tachycardia to ventricular fibrillation during acute regional ischemia is the subendocardial Purkinje system. After selective destruction of the Purkinje network by lugol, reentrant tachycardias still develop in the ischemic region, but they do not degenerate into fibrillation. Finally, attempts were made to determine the minimal mass of thin ventricular myocardium required to sustain fibrillation induced by burst pacing. This was done by freezing of subendocardial and midmural layers. The rim of surviving epicardial muscle had to be larger than 20 g. Extracellular electrograms during fibrillation in both the intact and the "frozen" left ventricle were indistinguishable, but activation patterns were markedly different. In the intact ventricle epicardial activation was compatible with multiple wavelet reentry, in the "frozen" heart a single, or at most two wandering reentrant waves were seen.

  17. Right ventricular assistance for experimental right ventricular dysfunction.

    PubMed

    Jett, G K; Applebaum, R E; Clark, R E

    1986-08-01

    Right ventricular dysfunction frequently occurs in patients undergoing correction of congenital cardiac defects, as well as in other clinical settings. The purpose of the present study was to surgically induce right ventricular dysfunction and then provide circulatory support with a right ventricular assist device. Right ventricular hypertrophy was created in 13 neonatal lambs by pulmonary artery banding. Right ventricular dysfunction was produced in all animals by performing a right ventriculotomy with the animal supported by cardiopulmonary bypass. In four unassisted animals the circulation failed after separation from bypass. Seven experimental animals underwent the insertion of a pneumatically activated ventricular assist device between the proximal pulmonary artery and the right ventricular apex. Periods with the right ventricular assist device on and off in each animal were compared. The right ventricular assist device increased cardiac output from 0.72 +/- 0.15 to 2.24 +/- 0.23 L/min (p less than 0.0002), increased left atrial pressure from 7 +/- 1 to 11 +/- 1 mm Hg (p less than 0.0005), and increased aortic systolic pressure from 53 +/- 9 to 85 +/- 9 mm Hg (p less than 0.0001). Right ventricular assistance significantly reduced the right ventricular end-diastolic pressure from 19 +/- 3 to 12 +/- 1 mm Hg (p less than 0.0001). Pulmonary artery peak pressure distal to the band increased from 27 +/- 3 to 52 +/- 5 mm Hg (p less than 0.0001). The results indicate that right ventricular dysfunction can be produced by a vertical cardiotomy in a hypertrophied right ventricle with persistent outflow tract obstruction. Right ventricular dysfunction can be effectively reversed by a right ventricular assist device, which may prove clinically useful in managing patients with refractory right ventricular failure.

  18. N = 2 Maxwell-Einstein Supergravity theories: their compact and non-compact gaugings and Jordan algebras

    SciTech Connect

    Guenaydin, M.; Sierra, G.; Townsend, P.K.

    1985-01-01

    In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is followed by a complete classification of the N = 2 MESGT's whose target manifolds parametrized by the scalar fields are symmetric spaces. 39 refs.

  19. Action of ATP on ventricular automaticity.

    PubMed

    Stark, G; Domanowits, H; Sterz, F; Stark, U; Bachernegg, M; Kickenweiz, E; Decrinis, M; Laggner, A N; Tritthart, H A

    1994-11-01

    ATP is an effective treatment of supraventricular tachycardia when the atrioventricular (AV) node is part of the reentrant circuit. However, the lower a pace-maker in the pacemaker hierarchy, the more sensitive it is to adenosine. Therefore, we investigated the effects of ATP on ventricular automaticity in in vivo and in vitro conditions. Wide and narrow QRS complex tachycardia in 46 patients was treated with 6, 12, and 18 mg ATP as sequential intravenous (i.v.) bolus. ATP terminated tachycardias in 67%. Bolus infusion ATP caused < or = 6.4-s asystole that was self-limited. Perfusion of isolated spontaneously beating guinea pig heart with 100 microM ATP completely suppressed ventricular automaticity. After ATP-infusion was discontinued, the first ventricular beat was evident after 3.1 +/- 0.9 s and sinus node activity recovered with a time constant of 3.0 +/- 1.1 s. Because sinus node and ventricular automaticity recovered within seconds after ATP infusion was discontinued in vitro, recovery in vivo is also likely to be determined by the short half-life (+1/2) of ATP. PMID:7532751

  20. Right Ventricular Myxoma.

    PubMed

    Vadivelmurugan, S; Senthamarai; Sakthimohan; Janarthanan; Balanayagam; Anand, Vijay; Venkateswaran, K J; Ramkumar; Selvaraj

    2015-10-01

    We report a case of 30 year female who presented with complaints of intermittent chest pain and breathlessness for 8 months, Diagnosed to have right ventricular mass protruding into main pulmonary artery during each systole. The mass was completely excised. Histopathological examination showed myxoma. PMID:27608701

  1. Aorto-ventricular tunnel.

    PubMed

    McKay, Roxane

    2007-10-08

    Aorto-ventricular tunnel is a congenital, extracardiac channel which connects the ascending aorta above the sinutubular junction to the cavity of the left, or (less commonly) right ventricle. The exact incidence is unknown, estimates ranging from 0.5% of fetal cardiac malformations to less than 0.1% of congenitally malformed hearts in clinico-pathological series. Approximately 130 cases have been reported in the literature, about twice as many cases in males as in females. Associated defects, usually involving the proximal coronary arteries, or the aortic or pulmonary valves, are present in nearly half the cases. Occasional patients present with an asymptomatic heart murmur and cardiac enlargement, but most suffer heart failure in the first year of life. The etiology of aorto-ventricular tunnel is uncertain. It appears to result from a combination of maldevelopment of the cushions which give rise to the pulmonary and aortic roots, and abnormal separation of these structures. Echocardiography is the diagnostic investigation of choice. Antenatal diagnosis by fetal echocardiography is reliable after 18 weeks gestation. Aorto-ventricular tunnel must be distinguished from other lesions which cause rapid run-off of blood from the aorta and produce cardiac failure. Optimal management of symptomatic aorto-ventricular tunnel consists of diagnosis by echocardiography, complimented with cardiac catheterization as needed to elucidate coronary arterial origins or associated defects, and prompt surgical repair. Observation of the exceedingly rare, asymptomatic patient with a small tunnel may be justified by occasional spontaneous closure. All patients require life-long follow-up for recurrence of the tunnel, aortic valve incompetence, left ventricular function, and aneurysmal enlargement of the ascending aorta.

  2. Prevalence, Patterns, and Clinical Predictors of Left Ventricular Late Gadolinium Enhancement in Patients Undergoing Cardiac Magnetic Resonance Prior to Pulmonary Vein Antral Isolation for Atrial Fibrillation: A Cross-Sectional Observational Study.

    PubMed

    Nance, John W; Khurram, Irfan M; Nazarian, Saman; DeWire, Jane; Calkins, Hugh; Zimmerman, Stefan L

    2015-09-01

    Cardiac magnetic resonance (CMR) imaging is increasingly used to evaluate patients with atrial fibrillation (AF) before pulmonary vein antral isolation (PVAI). The purpose of this study was to assess the incidence and pattern of left ventricular (LV) late gadolinium enhancement (LGE) in patients undergoing CMR before PVAI and compare the clinical and demographic differences of patients with and without LV LGE. Clinical and demographic data on 62 patients (mean age 61 ± 7.9, 69% male) undergoing CMR before PVAI for AF were collected. Two observers, masked to clinical histories, independently recorded the prevalence, extent (number of myocardial segments), and pattern (subendocardial, midmyocardial, or subepicardial) of LV LGE in each patient. Clinical and demographic predictors of LV LGE were determined using logistic regression. Twenty-three patients (37%) demonstrated LV LGE affecting a mean of 3.0 ± 2.1 myocardial segments. There was no difference in LV ejection fraction between patients with and without LGE, and most (65%) patients with LGE had normal wall motion. Only age (P = 0.04) and a history of congestive heart failure (P = .03) were statistically significant independent predictors of LGE. The most common LGE pattern was midmyocardial, seen in 17 of 23 (74%) patients. Only 4 of 23 (17%) patients had LGE in an "expected" pattern based on clinical history. Of the remaining 19 patients, 4 had known congestive heart failure, 5 nonischemic cardiomyopathy, 4 known coronary artery disease, and 2 prior aortic valve replacement. Six of 23 (26%) patients had no known coronary artery, valvular, or myocardial disease. There is a high prevalence of unexpected LV scar in patients undergoing CMR before PVAI for AF, with most patients demonstrating a nonischemic pattern of LV LGE and no wall motion abnormalities (ie, subclinical disease). The high prevalence of unexpected LGE in these patients may argue for CMR as the modality of choice for imaging

  3. Transcatheter device closure of pseudoaneurysms of the left ventricular wall: An emerging therapeutic option.

    PubMed

    Madan, Tarun; Juneja, Manish; Raval, Abhishek; Thakkar, Bhavesh

    2016-02-01

    Left ventricular pseudoaneurysm is a rare but serious complication of acute myocardial infarction and cardiac surgery. While surgical intervention is the conventional therapeutic option, transcatheter closure can be considered in selected patients with suitable morphology of the pseudoaneurysm. We report a case of successful transcatheter closure of a left ventricular pseudoaneurysm orifice and isolation of the sac using an Amplatzer septal occluder.

  4. Anger and ventricular arrhythmias

    PubMed Central

    Lampert, Rachel

    2011-01-01

    Purpose of review Although anecdotal evidence has long suggested links between emotion and ventricular arrhythmia, more recent studies have prospectively demonstrated the arrhythmogenic effects of anger, as well as mechanisms underlying these effects. Recent findings Epidemiological studies reveal that psychological stress increases sudden death, as well as arrhythmias, in patients with implantable cardioverter-defibrillators, in populations during emotionally devastating disasters such as earthquake or war. Diary-based studies confirm that anger and other negative emotions can trigger potentially lethal ventricular arrhythmias. Anger alters electrophysiological properties of the myocardium, including T-wave alternans, a measure of heterogeneity of repolarization, suggesting one mechanistic link between emotion and arrhythmia. Pilot studies of behavioral interventions have shown promise in decreasing arrhythmias in patients with implantable cardioverter-defibrillators. Summary Anger and other strong emotions can trigger polymorphic, potentially life-threatening ventricular arrhythmias in vulnerable patients. Through autonomic changes including increased sympathetic activity and vagal withdrawal, anger leads to increases in heterogeneity of repolarization as measured by T-wave alternans, known to be associated with arrhythmogenesis, as well as increasing inducibility of arrhythmia. Further delineation of mechanisms linking anger and arrhythmia, and of approaches to decrease the detrimental effects of anger and other negative emotions on arrhythmogenesis, are important areas of future investigation. PMID:19864944

  5. [Ventricular septal perforation].

    PubMed

    Ohno, Nobuhisa; Komeda, Masaharu

    2004-07-01

    As a mechanical complication of acute myocardial infarction, ventricular septal perforation (VSP) occurs mostly within 1 week after infarction. Although incidence of the disease is only 1-2% of transmural infarction, patients are into serious condition progressively once it happens. Even if patients were treated medically under intensive care protocol, they would almost always present congestive heart failure due to massive volume overload. Hence VSP should be treated surgically as soon as possible after its onset. We believe that infarct exclusion technique is standard procedure of surgical treatment, because it is relatively simple, makes less bleeding and gives minimal damage to right ventricle. Acute mortality has come down to 10-20% after introduction of this procedure. Cardiogenic shock before surgery, severe right heart failure and high age are important predictors of death. It is still difficult to save patients who are in severe cardiogenic shock with very low ventricular function. New treatments such as ventricular assist device, heart transplantation and regeneration therapy are waited for this high risk group of patients.

  6. Significance of postshunt ventricular asymmetries.

    PubMed

    Linder, M; Diehl, J T; Sklar, F H

    1981-08-01

    Ventricular asymmetries after shunt surgery were studied. Right and left ventricular areas from pre-and postoperative computerized tomography scans were measured with a computer digitizing technique, and the respective areas were expressed as a ratio. Measurements were made from the scans of 15 hydrocephalic children selected at random. Ages at surgery ranged from 1 to 101 weeks. The results indicate a significantly greater decrease in ventricular size on the side of the ventricular shunt catheter. Multiple regression analysis showed no relationship between the magnitude of change in ventricular size and either the patients' age orn the time intervals between surgery and follow-up scans. Possible mechanisms for these postshunt ventricular asymmetries are discussed.

  7. Imaging for the Diagnosis of an Unusual Case of Left Ventricular Aneurysm

    SciTech Connect

    Russo, G. Sarais, C.; Corbetti, F.; Ramondo, A.; Daliento, L.

    2005-04-15

    An isolated ventricular diverticulum in an adult patient investigated for chest pain is reported. An exhaustive diagnosis was obtained by different means and complementary imaging techniques such as echocardiography, cardiovascular magnetic resonance imaging and cineangiography.

  8. Noncompact three-dimensional quantum electrodynamics with N{sub f}=1 and N{sub f}=4

    SciTech Connect

    Hands, S.J.; Kogut, J.B.; Scorzato, L.; Strouthos, C.G.

    2004-09-01

    We present numerical results for noncompact three-dimensional quantum electrodynamics for numbers of flavors N{sub f}=1 and N{sub f}=4. In particular, we address the issue of whether chiral symmetry is spontaneously broken in the continuum limit, and obtain a positive answer for N{sub f}=1, with a dimensionless condensate estimated to be {beta}{sup 2}<{psi}{psi}>{approx_equal}O(10{sup -3}), implying that the critical number of flavors N{sub fc}>1. We also compare the N{sub f}=1 and N{sub f}=4 models by analyzing the transition from strong to weak coupling behavior using an equation of state based on a continuous phase transition. While some qualitative differences emerge, it appears difficult to determine whether N{sub f}=4 lies above or below N{sub fc}.

  9. Postpartal right ventricular thrombosis.

    PubMed

    Velicki, Lazar; Milosavljević, Aleksandar; Majin, Marijan; Vujin, Bojan; Kovacević, Pavle

    2008-11-01

    The discovery of an intracardial mass in patients presents a serious diagnostic dilemma. The differential diagnosis of this condition may seem abundant, but myxomas and intracardial thrombosis are the most frequent diagnoses. A connection between pregnancy and the presence of thrombosis has been documented frequently. Normal pregnancy leads to changes of the coagulative and fibrinolytic status toward a hypercoagulable condition which has its own physiological justification (the risk of blood loss decreases during labor). The case of a patient suffering from postpartal right ventricular thrombosis, which was successfully resolved by surgery as described in this contribution, demonstrates the value of a multidisciplinary approach.

  10. [Catheter ablation of focus triggering ventricular fibrillation in patients with structural heart disease].

    PubMed

    Kautzner, Josef; Peichl, Petr

    2014-12-01

    First experiences with ablation of focus triggering ventricular fibrillation were reported in isolated cases of idiopathic ventricular fibrillation. Later, there were described the options in management of an electrical instability triggered by ectopic activity in patients after myocardial infarction. In both cases it was shown that the sources of extrasystoles originate almost exclusively from conducting system of chambers. Subsequently, isolated cases were also reported in other structural diseases. It is important that the urgent catheter ablation is able to remove focus which triggers electric instability. In many cases it is a lifesaving procedure. This review summarizes the current knowledge of the catheter ablation of focus triggering ventricular fibrillation with structural heart disease.

  11. Overlapping left ventricular restoration.

    PubMed

    Matsui, Yoshiro

    2009-06-01

    Cardiac transplantation, a final option of treatment for refractory heart failure, has not been a standard procedure in Japan especially, mainly because of the shortage of donors. However, surgical methods to restore native heart function, such as surgical ventricular restoration (SVR), are often effective for these cases. The Dor procedure has been used for ischemic cardiomyopathy cases presenting with broad akinetic segments. This is a fine method to exclude the scarred septum and to reduce the intraventricular cavity by encircling purse-string suture, but it may produce a postoperative spherical ventricular shape as a result of endoventricular patch repair. Also, partial left ventriculectomy is not recommended for non-ischemic dilated cardiomyopathy cases for now. A modification of these SVR and surgical approaches to functional mitral regurgitation has been named "overlapping ventriculoplasty" without endoventricular patch and resection of viable cardiac muscle, and "mitral complex reconstruction", which consists of mitral annuloplasty, papillary muscle approximation, and suspension. Although the long-term prognosis of these procedures is undetermined, they could be an important option, at least as an alternative bridge to transplantation. This review will describe the concepts and some technical aspects of these procedures for the end-stage heart. PMID:19474505

  12. Nonischemic Left Ventricular Scar as a Substrate of Life-Threatening Ventricular Arrhythmias and Sudden Cardiac Death in Competitive Athletes

    PubMed Central

    Zorzi, Alessandro; Perazzolo Marra, Martina; Rigato, Ilaria; De Lazzari, Manuel; Susana, Angela; Niero, Alice; Pilichou, Kalliopi; Migliore, Federico; Rizzo, Stefania; Giorgi, Benedetta; De Conti, Giorgio; Sarto, Patrizio; Serratosa, Luis; Patrizi, Giampiero; De Maria, Elia; Pelliccia, Antonio; Basso, Cristina; Schiavon, Maurizio; Bauce, Barbara; Iliceto, Sabino; Thiene, Gaetano

    2016-01-01

    Background— The clinical profile and arrhythmic outcome of competitive athletes with isolated nonischemic left ventricular (LV) scar as evidenced by contrast-enhanced cardiac magnetic resonance remain to be elucidated. Methods and Results— We compared 35 athletes (80% men, age: 14–48 years) with ventricular arrhythmias and isolated LV subepicardial/midmyocardial late gadolinium enhancement (LGE) on contrast-enhanced cardiac magnetic resonance (group A) with 38 athletes with ventricular arrhythmias and no LGE (group B) and 40 healthy control athletes (group C). A stria LGE pattern with subepicardial/midmyocardial distribution, mostly involving the lateral LV wall, was found in 27 (77%) of group A versus 0 controls (group C; P<0.001), whereas a spotty pattern of LGE localized at the junction of the right ventricle to the septum was respectively observed in 11 (31%) versus 10 (25%; P=0.52). All athletes with stria pattern showed ventricular arrhythmias with a predominant right bundle branch block morphology, 13 of 27 (48%) showed ECG repolarization abnormalities, and 5 of 27 (19%) showed echocardiographic hypokinesis of the lateral LV wall. The majority of athletes with no or spotty LGE pattern had ventricular arrhythmias with a predominant left bundle branch block morphology and no ECG or echocardiographic abnormalities. During a follow-up of 38±25 months, 6 of 27 (22%) athletes with stria pattern experienced malignant arrhythmic events such as appropriate implantable cardiac defibrillator shock (n=4), sustained ventricular tachycardia (n=1), or sudden death (n=1), compared with none of athletes with no or LGE spotty pattern and controls. Conclusions— Isolated nonischemic LV LGE with a stria pattern may be associated with life-threatening arrhythmias and sudden death in the athlete. Because of its subepicardial/midmyocardial location, LV scar is often not detected by echocardiography. PMID:27390211

  13. Arrhythmogenic right ventricular cardiomyopathy in a weimaraner

    PubMed Central

    Eason, Bryan D.; Leach, Stacey B.; Kuroki, Keiichi

    2015-01-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) was diagnosed postmortem in a weimaraner dog. Syncope, ventricular arrhythmias, and sudden death in this patient combined with the histopathological fatty tissue infiltration affecting the right ventricular myocardium are consistent with previous reports of ARVC in non-boxer dogs. Arrhythmogenic right ventricular cardiomyopathy has not been previously reported in weimaraners. PMID:26483577

  14. Right ventricular apex pacing: is it obsolete?

    PubMed

    Sanaa, Islem; Franceschi, Frédéric; Prevot, Sébastien; Bastard, Emilie; Deharo, Jean-Claude

    2009-02-01

    Clinical trials in patients with pacemakers for sinus node dysfunction or atrioventricular block have highlighted the fact that desynchronization of ventricular contraction induced by right ventricular apical pacing is associated with long-term morbidity and mortality. These clinical data confirm pathophysiological results indicating that right ventricular apical pacing causes abnormal ventricular contraction, reduces pump function and leads to myocardial hypertrophy and ultrastructural abnormalities. In this manuscript, we discuss the clinical evidence for the adverse and beneficial effects of various right ventricular pacing sites, left ventricular pacing sites and biventricular pacing. We also propose a decisional algorithm for pacing modalities, based on atrioventricular conduction, left ventricular function and expected lifespan. PMID:19303581

  15. Facts about Ventricular Septal Defect

    MedlinePlus

    ... The size of the ventricular septal defect will influence what symptoms, if any, are present, and whether ... this image. Close Information For... Media Policy Makers Language: English Español (Spanish) File Formats Help: How do ...

  16. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

    NASA Astrophysics Data System (ADS)

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-01

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  17. The relationship of left ventricular trabeculation to ventricular function and structure over 9.5 years follow up: the Multi-Ethnic Study of Atherosclerosis

    PubMed Central

    Zemrak, Filip; Ahlman, Mark A.; Captur, Gabriella; Mohiddin, Saidi A; Kawel-Boehm, Nadine; Prince, Martin R.; Moon, James C.; Hundley, William G.; Lima, João A.C.; Bluemke, David A; Petersen, Steffen E

    2015-01-01

    Background Left ventricular (LV) trabeculation is highly variable between individuals, is increased in some diseases (e.g. congenital heart disease or cardiomyopathies), but its significance in population representative individuals is unknown. Objectives To determine if excessive LV trabeculation in population representative subjects is associated with preceding changes in cardiac volumes and function. Methods The extent of trabeculation, expressed as the ratio of non-compacted to compacted (NC/C) myocardium was measured for technical reasons on cardiac magnetic resonance (CMR) long-axis cine images in 2742 subjects in the Multi-Ethnic Study of Atherosclerosis (mean age 68.7 years, 52.3% women, 56.4% with hypertension, 16.8% with diabetes) at the exam 5. These were considered in quintiles of trabeculation extent, with quintile 5’s NC/C 2.46 – 5.41. We determined the relationship between maximal NC/C ratio and preceding change (9.5 year between exam 1 and 5) in end-systolic volume indexed to the body surface area (ESVi). Secondary analysis assessed associations between maximal NC/C and preceding changes in end-diastolic volume indexed to the body surface area (EDVi) and ejection fraction (EF). Results Over 9.5 years, ESVi decreased by 1.3 ml/m2, EDVi decreased by 5.1 ml/m2 and EF decreased by 0.6% (p<0.0001). There were no clinically relevant differences in LV volumes and systolic function change between the quintiles of trabeculation extent, even in subjects with the excessive trabeculation. Conclusions Greater extent of and even excessive LV trabeculations measured in end-diastole in asymptomatic population representative individuals appears benign and is not associated with deterioration in left ventricular volumes or function over an almost 10 year period. PMID:25440091

  18. Catheter ablation of a monofocal premature ventricular complex triggering idiopathic ventricular fibrillation.

    PubMed

    Takatsuki, S; Mitamura, H; Ogawa, S

    2001-07-01

    A 62 year old man was admitted for evaluation of recurrent episodes of syncope. A surface ECG showed frequent repetitive premature ventricular complexes of right ventricular outflow tract origin. Ventricular fibrillation was inducible by programmed electrical stimulation but otherwise cardiac evaluation was unremarkable. A diagnosis of idiopathic ventricular fibrillation was made and an implantable cardioverter-defibrillator (ICD) was installed. However, spontaneous ventricular fibrillation recurred, requiring repeated ICD discharges. The ventricular fibrillation was reproducibly triggered by a single premature ventricular complex with a specific QRS morphology. Radiofrequency catheter ablation was carried out to eradicate this complex. No ventricular fibrillation has developed after this procedure, and the patient does not require drug treatment.

  19. Epicardial Ablation of Ventricular Tachycardia

    PubMed Central

    Tung, Roderick; Shivkumar, Kalyanam

    2015-01-01

    Epicardial mapping and ablation via a percutaneous subxiphoid technique has been instrumental in improving the working understanding of complex myocardial scars in various arrhythmogenic substrates. Endocardial ablation alone may not be sufficient in patients with ischemic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and Chagas disease to prevent recurrent ventricular tachycardia. Multiple observational studies have demonstrated greater freedom from recurrence with adjunctive epicardial ablation compared with endocardial ablation alone. While epicardial ablation is performed predominantly at tertiary referral centers, knowledge of the technical approach, clinical indications, and potential complications is imperative to maximizing clinical success and patient safety. In 1996, Sosa and colleagues modified the pericardiocentesis technique to enable percutaneous access to the pericardial space for mapping and catheter ablation of ventricular tachycardia.1 Originally developed for patients with epicardial scarring due to chagasic cardiomyopathy and patients with ischemic cardiomyopathy refractory to endocardial ablationm,2,3 this approach has since become an essential part of the armamentarium for the treatment of ventricular tachycardia. Myocardial scars are three-dimensionally complex with varying degrees of transmurality, and the ability to map and ablate the epicardial surface has contributed to a greater understanding of scar-related VT in postinfarction cardiomyopathy and nonischemic substrates including idiopathic dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, and chagasic cardiomyopathy. In this review, we highlight the percutaneous approach and discuss clinical indications and potential complications. PMID:26306131

  20. Molecular mechanisms of ventricular hypoplasia.

    PubMed

    Srivastava, D; Gottlieb, P D; Olson, E N

    2002-01-01

    We have established the beginnings of a road map to understand how ventricular cells become specified, differentiate, and expand into a functional cardiac chamber (Fig. 5). The transcriptional networks described here provide clear evidence that disruption of pathways affecting ventricular growth could be the underlying etiology in a subset of children born with malformation of the right or left ventricle. As we learn details of the precise mechanisms through which the critical factors function, the challenge will lie in devising innovative methods to augment or modify the effects of gene mutations on ventricular development. Because most congenital heart disease likely occurs in a setting of heterozygous, predisposing mutations of one or more genes, modulation of activity of critical pathways in a preventive fashion may be useful in averting disease in genetically susceptible individuals. PMID:12858532

  1. Genetics Home Reference: catecholaminergic polymorphic ventricular tachycardia

    MedlinePlus

    ... for This Page Cerrone M, Napolitano C, Priori SG. Catecholaminergic polymorphic ventricular tachycardia: A paradigm to understand ... on PubMed Central Liu N, Ruan Y, Priori SG. Catecholaminergic polymorphic ventricular tachycardia. Prog Cardiovasc Dis. 2008 ...

  2. Analysis of Ventricular Function by Computed Tomography

    PubMed Central

    Rizvi, Asim; Deaño, Roderick C.; Bachman, Daniel P.; Xiong, Guanglei; Min, James K.; Truong, Quynh A.

    2014-01-01

    The assessment of ventricular function, cardiac chamber dimensions and ventricular mass is fundamental for clinical diagnosis, risk assessment, therapeutic decisions, and prognosis in patients with cardiac disease. Although cardiac computed tomography (CT) is a noninvasive imaging technique often used for the assessment of coronary artery disease, it can also be utilized to obtain important data about left and right ventricular function and morphology. In this review, we will discuss the clinical indications for the use of cardiac CT for ventricular analysis, review the evidence on the assessment of ventricular function compared to existing imaging modalities such cardiac MRI and echocardiography, provide a typical cardiac CT protocol for image acquisition and post-processing for ventricular analysis, and provide step-by-step instructions to acquire multiplanar cardiac views for ventricular assessment from the standard axial, coronal, and sagittal planes. Furthermore, both qualitative and quantitative assessments of ventricular function as well as sample reporting are detailed. PMID:25576407

  3. Left Ventricular Assist Devices

    PubMed Central

    2004-01-01

    Executive Summary Objective The objective of this health technology policy assessment was to determine the effectiveness and cost-effectiveness of using implantable ventricular assist devices in the treatment of end-stage heart failure. Heart Failure Heart failure is a complex syndrome that impairs the ability of the heart to maintain adequate blood circulation, resulting in multiorgan abnormalities and, eventually, death. In the period of 1994 to 1997, 38,702 individuals in Ontario had a first hospital admission for heart failure. Despite reported improvement in survival, the five-year mortality rate for heart failure is about 50%. For patients with end-stage heart failure that does not respond to medical therapy, surgical treatment or traditional circulatory assist devices, heart transplantation (in appropriate patients) is the only treatment that provides significant patient benefit. Heart Transplant in Ontario With a shortage in the supply of donor hearts, patients are waiting longer for a heart transplant and may die before a donor heart is available. From 1999 to 2003, 55 to 74 people received a heart transplant in Ontario each year. Another 12 to 21 people died while waiting for a suitable donor heart. Of these, 1 to 5 deaths occurred in people under 18 years old. The rate-limiting factor in heart transplant is the supply of donor hearts. Without an increase in available donor hearts, attempts at prolonging the life of some patients on the transplant wait list could have a harmful effect on other patients that are being pushed down the waiting list (knock on effect). LVAD Technology Ventricular assist devices [VADs] have been developed to provide circulatory assistance to patients with end-stage heart failure. These are small pumps that usually assist the damaged left ventricle [LVADs] and may be situated within the body (intracorporeal] or outside the body [extracorporeal). Some of these devices were designed for use in the right ventricle [RVAD] or both

  4. [Fulguration of extrasystolic ventricular focus].

    PubMed

    Velázquez Rodríguez, E; Rosas, F; Frank, R; Fontaine, G; Tonet, J; Lascault, G; Gallais, Y

    1995-01-01

    A case is presented of symptomatic premature ventricular contractions refractory to drug therapy with right bundle branch block QRS morphology and left axis deviation in a 68-year-old female without structural heart disease. Endocardial mapping localized the extrasystolic focus at meso-inferoapical region of the left ventricular septum suggesting an origin from the Purkinje network of the left posterior fascicle. Catheter ablation with direct-current energy abolished extrasystolic complexes, without complications. The patient remained asymptomatic over a follow-up of 3 months. PMID:7543744

  5. Catheter ablation of a polymorphic ventricular tachycardia inducing monofocal premature ventricular complex.

    PubMed

    Uemura, Takashi; Yamabe, Hiroshige; Tanaka, Yasuaki; Morihisa, Kenji; Kawano, Hiroaki; Kaikita, Koichi; Sumida, Hitoshi; Sugiyama, Seigo; Ogawa, Hisao

    2008-01-01

    Ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is considered benign, but sometimes it causes polymorphic ventricular tachycardia and ventricular fibrillation, resulting in sudden cardiac death. A 58-year-old woman without structural heart disease was admitted for evaluation of recurrent episodes of syncope. Surface ECG showed frequent repetitive premature ventricular contraction (PVC) of RVOT origin. Polymorphic ventricular tachycardia triggered by the same PVC was documented by Holter ECG during an episode of syncope. Radiofrequency catheter ablation was performed to eradicate this PVC. No polymorphic ventricular tachycardia has developed after the procedure, and the patient has had no recurrence of syncope.

  6. Allicin inhibits transient outward potassium currents in mouse ventricular myocytes

    PubMed Central

    CAO, HONG; HUANG, CONGXIN; WANG, XIN

    2016-01-01

    Allicin is the active constituent of garlic, a widely used spice and food. The remedial properties of garlic have also been extensively researched and it has been demonstrated that allicin is able to inhibit the transient outward potassium current (Ito) in atrial myocytes. However, the direct effect of allicin on Ito in ventricular myocytes has yet to be elucidated. In the present study, the effects of allicin on Ito in ventricular myocytes isolated from mice were investigated, using the whole-cell patch recording technique. The results revealed that Ito current was not significantly suppressed by allicin in the low-dose group (10 µmol/l; P>0.05). However, Ito was significantly inhibited by higher doses of allicin (30, 100 and 300 µmol/l; P<0.05 vs. control; n=6) in a concentration-dependent manner (IC50=41.6 µmol/l). In addition, a high concentration of allicin (≥100 µmol/l) was able to accelerate the voltage-dependent inactivation of Ito in mouse ventricular myocytes. In conclusion, the present study revealed that allicin inhibited the Ito in mouse ventricular myocytes, which may be the mechanism through which allicin exerts its antiarrhythmic effect. PMID:27168824

  7. Prevention of Ventricular Arrhythmia and Calcium Dysregulation in a Catecholaminergic Polymorphic Ventricular Tachycardia Mouse Model Carrying Calsequestrin-2 Mutation

    PubMed Central

    Alcalai, Ronny; Wakimoto, Hiroko; Arad, Michael; Planer, David; Konno, Tetsuo; Wang, Libin; Seidman, Jon G.; Seidman, Christine E.; Berul, Charles I

    2010-01-01

    Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial arrhythmic syndrome caused by mutations in genes encoding the calcium-regulation proteins cardiac ryanodine receptor (RyR2) or calsequestrin-2 (CASQ2). Mechanistic studies indicate that CPVT is mediated by diastolic Ca2+ overload and increased Ca2+ leak through the RyR2 channel, implying that treatment targeting these defects might be efficacious in CPVT. Method and results CPVT mouse models that lack CASQ2 were treated with Ca2+-channel inhibitors, β-adrenergic inhibitors, or Mg2+. Treatment effects on ventricular arrhythmia, sarcoplasmic reticulum (SR) protein expression and Ca2+ transients of isolated myocytes were assessed. Each study agent reduced the frequency of stress-induced ventricular arrhythmia in mutant mice. The Ca2+ channel blocker verapamil was most efficacious and completely prevented arrhythmia in 85% of mice. Verapamil significantly increased the SR Ca2+ content in mutant myocytes, diminished diastolic Ca2+ overload, increased systolic Ca2+ amplitude, and prevented Ca2+ oscillations in stressed mutant myocytes. Conclusions Ca2+ channel inhibition by verapamil rectified abnormal calcium handling in CPVT myocytes and prevented ventricular arrhythmias. Verapamil-induced partial normalization of SR Ca2+ content in mutant myocytes implicates CASQ2 as modulator of RyR2 activity, rather than or in addition to, Ca2+ buffer protein. Agents such as verapamil that attenuate cardiomyocyte calcium overload are appropriate for assessing clinical efficacy in human CPVT. PMID:20807279

  8. Ventricular arrhythmias: state of the art.

    PubMed

    Schleifer, J William; Srivathsan, Komandoor

    2013-11-01

    The management of ventricular tachycardia and ventricular fibrillation in the cardiac intensive care unit can be complex. These arrhythmias have many triggers, including ischemia, sympathetic stimulation, and medication toxicities, as well as many different substrates, ranging from ischemic and nonischemic cardiomyopathies to rare genetic conditions such as Brugada syndrome and long QT syndrome. Different settings, such as congenital heart disease, postoperative ventricular arrhythmias, and ventricular assist devices, increase the complexity of management. This article reviews the variety of situations and cardiac conditions that give rise to ventricular arrhythmias, focusing on inpatient management strategies.

  9. Two Types of Calcium Channels in Guinea Pig Ventricular Myocytes

    NASA Astrophysics Data System (ADS)

    Mitra, Raman; Morad, Martin

    1986-07-01

    In cardiac muscle, Ca2+ plays a key role in regulation of numerous processes, including generation of the action potential and development of tension. The entry of Ca2+ into the cell is regulated primarily by voltage-gated channels in the membrane. Until recently, it was felt that only one type of Ca2+ channel existed in cardiac ventricular muscle. Experiments reported here suggest that in isolated guinea pig ventricular myocytes, there are two distinct types of Ca2+ channels with markedly different activation thresholds, inactivation kinetics, and sensitivities to inorganic and organic Ca2+ channel blockers. The channels were also distinguished based on their response to increased frequency of clamping such that the current through the low-threshold channel decreased while that through the high-threshold channel increased. In a few cells, the current through both channels was enhanced by isoproterenol, a β -adrenergic agonist, but only the high-threshold channel was enhanced by the Ca2+-channel agonist Bay K 8644. Thus, isolated guinea pig ventricular myocytes appear to have two types of Ca2+ channels distinguished by various criteria.

  10. Congenital left ventricular apical aneurysm presenting as ventricular tachycardia.

    PubMed

    Amado, José; Marques, Nuno; Candeias, Rui; Gago, Paula; de Jesus, Ilídio

    2016-10-01

    The authors present the case of a 34-year-old male patient seen in our department due to palpitations. On the electrocardiogram monomorphic ventricular tachycardia (VT) was documented, treated successfully with amiodarone. The subsequent study revealed a normal echocardiogram and an apical aneurysm of the left ventricle on magnetic resonance imaging, confirmed by computed tomography coronary angiography that also excluded coronary disease. He underwent an electrophysiological study to determine the origin of the VT and to perform catheter ablation using electroanatomical mapping. VT was induced and radiofrequency applications were performed in the left ventricular aneurysm area. VT was no longer inducible, with acute success. Despite this it was decided to implant a subcutaneous implantable cardioverter-defibrillator (ICD). Eight months after the ablation the patient was admitted again due to VT, treated by the ICD.

  11. Mechanics of left ventricular aneurysm.

    PubMed

    Radhakrishnan, S; Ghista, D N; Jayaraman, G

    1986-01-01

    When a coronary artery is significantly occluded, the left ventricular myocardial segment, which is perfused by that coronary artery, will become ischaemic and even irreversibly infarcted. An acute infarct has very low stiffness and if it involves the entire wall there is a risk of rupture; however, in the absence of such a critical situation, fibrous tissue is laid into the infarcted myocardial segment. Such an infarcted fibrotic myocardial segment will not be able to contract, and so generate tensile stress. The surrounding intact myocardium will contract and generate wall stress, thereby developing a high intra-chamber systolic pressure; the chronically infarcted and fibrotic segment will have to sustain this high chamber pressure. Its loss of contractility and the resulting reduced systolic stiffness relative to the intact segment, will cause it to deform into a bulge; this is an aneurysm. When a left ventricular chamber with an aneurysm contracts during the systolic phase, some blood also goes into the aneurysm, and this decreases the stroke volume; since the aneurysm wall is passive, stagnant blood flow prevails in the aneurysm itself, which in turn can give rise to the formation of a mural thrombus. These serious consequences provide a justification for the analysis of an infarcted left ventricular chamber, in order to predict the size of the aneurysmic bulge. Such an analysis is presented in this paper. To determine the left ventricular wall deformation, and the stress arising from infarction of a wall segment (which leads to a ventricular aneurysm) the left ventricle is modelled here as a pressurized ellipsoidal shell. Deformations of infarcted wall segments are computed for several damaged wall-thicknesses in left ventricles of different shapes. The analysis involves a derivation of equations for wall-stress equilibrium with the chamber pressure, and myocardial incompressibility before and after infarct formation. The equations are solved by the Newton

  12. Heterogeneity of ventricular repolarization in newborns with severe aortic coarctation.

    PubMed

    Nigro, Gerardo; Russo, Vincenzo; Rago, Anna; Papa, Andrea Antonio; Cioppa, Nadia Della; Di Meo, Federica; Corcione, Antonio; Caianiello, Giuseppe; Russo, Maria Giovanna; Calabrò, Raffaele

    2012-02-01

    Sudden death is a possible occurrence for newborns younger than 1 year with severe aortic coarctation (CoA) before surgical correction. Basic research and animal experiments have shown electrophysiologic changes during mechanical ventricular pressure overload. The current study aimed to evaluate the effect of severe CoA on the heterogeneity of ventricular repolarization by examining corrected QT and JT interval dispersion (respectively, QTc-D and JTc-D) and electrocardiographic parameters of spatial heterogeneity of ventricular repolarization in newborns with no associated congenital cardiac malformations. The study enrolled 30 isolated severe CoA neonates (age, 45 ± 15 days; 17 males) with normal size and wall thickness of the left ventricle before surgical correction and 30 age- and sex-matched healthy newborns used as control subjects. Heart rate, QRS duration, maximum and minimum QT and JT intervals, and QTc-D and JTc-D measurements were performed. The healthy control group did not significantly differ from the CoA group in terms of heart rate, weight, height, and echocardiographic parameters. Compared with the healthy control group, the CoA group presented significantly increased values of QTc-D (109.7 ± 43.4 vs. 23 ± 15 ms; P = 0.03) and JTc-D (99.1 ± 43.3 vs. 65.8 ± 24.1 ms; P = 0.04). A statistically significant correlation was found between the Doppler peak pressure gradient across the coarctation site and the values of QTc-D (r = 0.48; P = 0.03) and JTc-D (r = 0.42; P = 0.04). Our study showed significantly increased QTc-D and JTc-D in isolated CoA newborns with normal left ventricular geometry. PMID:21968578

  13. Ventricular assist devices: initial orientation.

    PubMed

    Schweiger, Martin; Dave, Hitendu; Lemme, Frithjof; Romanchenko, Olga; Hofmann, Michael; Hübler, Michael

    2013-08-01

    Ventricular assist device (VAD) technology has come from large pulsatile-flow devices with a high rate of technical malfunctions to small continuous flow (cf) devices. Mechanical circulatory support (MCS) systems may be used as short-, mid- or long-term support. Especially if mid- or long-term support is anticipated left VADs (LVADs) have been reported with excellent one and two year survival rates and improved quality of life (QoL). Timing of implantation, patient selection, assessing function of the right ventricular and surgical considerations regarding surgical access side, valve pathology and exit side of the percutaneous lead remain crucial issues for the outcome. In contrast VADs designed for children especially for all age groups, are still underrepresented but increased experience with existing pediatric VADs as well as introduction of second and third generation VADs into in the pediatric age group, offer new perspectives.

  14. Ventricular assist devices: initial orientation

    PubMed Central

    Dave, Hitendu; Lemme, Frithjof; Romanchenko, Olga; Hofmann, Michael; Hübler, Michael

    2013-01-01

    Ventricular assist device (VAD) technology has come from large pulsatile-flow devices with a high rate of technical malfunctions to small continuous flow (cf) devices. Mechanical circulatory support (MCS) systems may be used as short-, mid- or long-term support. Especially if mid- or long-term support is anticipated left VADs (LVADs) have been reported with excellent one and two year survival rates and improved quality of life (QoL). Timing of implantation, patient selection, assessing function of the right ventricular and surgical considerations regarding surgical access side, valve pathology and exit side of the percutaneous lead remain crucial issues for the outcome. In contrast VADs designed for children especially for all age groups, are still underrepresented but increased experience with existing pediatric VADs as well as introduction of second and third generation VADs into in the pediatric age group, offer new perspectives. PMID:23991317

  15. Ventricular hypertrophy--physiological mechanisms.

    PubMed

    Vaughan Williams, E M

    1986-01-01

    Adult cardiac myocytes are incapable of mitosis. Dead cells are replaced by connective tissue so that after myocardial infarction (MI), function can only be restored by compensatory hypertrophy of the surviving myocardium. In physiological hypertrophy in response to exercise, high altitude, or mild hypertension, additional myoplasm expands cell diameter in an orderly fashion; Z-lines are in register and the normal ratio of volume densities of contractile elements, mitochondria, and capillaries is conserved. In hypertrophy induced by aortic or pulmonary artery banding or by experimental or congenital hypertension, the borderline between physiological and pathological hypertrophy may be crossed, causing disorganization of fibers and an unfavourable contractile element to capillary ratio. There was, therefore, a need for a graded model of hypertrophy, which involves simulating an altitude of 6,000 m at sea level by supplying rabbits with appropriate nitrogen/oxygen mixtures. In this environment, 50% right ventricular hypertrophy can be achieved without alteration of left ventricular weight or hematocrit. Longer exposures produced 100% right ventricular hypertrophy, with only moderate increases in hematocrit and left ventricular weight. It is well known that adrenergic stimulation causes cardiac hypertrophy, and it has been suggested that release of a trophic factor from sympathetic nerves, either noradrenaline or a protein, might be a necessary stimulus for growth. If so, long-term treatment of post-MI patients with beta-adrenergic blocking agents could inhibit a desirable compensatory hypertrophy of the surviving myocardium. In the above model it has been found, however, that neither beta-blockade nor chemical sympathectomy with guanethidine or 6-hydroxydopamine had any effect on the hypertrophy, nor did treatment with verapamil or nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Different effects of abnormal activation and myocardial disease on left ventricular ejection and filling times

    PubMed Central

    Zhou, Q; Henein, M; Coats, A; Gibson, D

    2000-01-01

    BACKGROUND—Ventricular activation is often abnormal in patients with dilated cardiomyopathy, but its specific effects on timing remain undetermined.
OBJECTIVE—To investigate the use of the ratio of the sum of left ventricular ejection and filling times to the total RR interval (Z ratio) to dissociate the effects of abnormal activation from those of cavity dilatation.
METHODS—Subjects were 20 normal individuals, 11 patients with isolated left bundle branch block (LBBB, QRS duration > 120 ms), 17 with dilated cardiomyopathy and normal activation, and 23 with dilated cardiomyopathy and LBBB. An additional 30 patients (nine with normal ventricular systolic function and 21 with dilated cardiomyopathy) were studied before and after right ventricular pacing. Left ventricular ejection and filling times were measured by pulsed wave Doppler and cavity size by M mode echocardiography.
RESULTS—Z ratio was independent of RR interval in all groups. Mean (SD) Z ratio was 82 (10)% for normal subjects, 66 (10)% for isolated LBBB (p < 0.01 v normal), 77 (7)% for dilated cardiomyopathy without LBBB (NS v normal), and 61 (7)% for dilated cardiomyopathy with LBBB (p < 0.01 v normal). In the nine patients with normal left ventricular size and QRS duration, Z ratio fell from 88 (6)% in sinus rhythm to 77 (10)% with right ventricular pacing (p = 0.26). In the 21 patients with dilated cardiomyopathy and LBBB, Z ratio rose from 59 (10)% in sinus rhythm to 74 (9)% with right ventricular DDD pacing (p < 0.001).
CONCLUSIONS—Z ratio dissociates the effects of abnormal ventricular activation and systolic disease. It also clearly differentiates right ventricular pacing from LBBB. It may thus be useful in comparing the haemodynamic effects of different pacing modes in patients with or without left ventricular disease.


Keywords: dilated cardiomyopathy; pacemaker; left bundle branch block; echocardiography. PMID:10956289

  17. Nomogram for calculation of left ventricular volumes.

    PubMed Central

    Saksena, F B; Saksena, G B

    1977-01-01

    A nomogram has been devised for the rapid derivation of left ventricular volumes from single-plane angiograms obtained in the 30 degrees right anterior oblique projection. The left ventricular volumes are derived from the use of the area-length formula of Dodge. The computed left ventricular volumes may then be adjusted to correspond to the actual volumes by an appropriate conversion chart. PMID:911567

  18. Regional myocardial shape and dimensions of the working isolated canine left ventricle

    NASA Technical Reports Server (NTRS)

    Ritman, E. L.; Tsuiki, K.; Donald, D.; Wood, E. H.

    1975-01-01

    The extent to which the dynamic shape and dimensions of the isolated left ventricular myocardial wall differ throughout the myocardium and how these differences are characteristic of the anatomic location was demonstrated. The use of a biplane X-ray technique and a metabolically-supported isolated canine left ventricle preparation provided an angiographically ideal means of measuring mechanical dynamics of the myocardium while the intact left ventricular myocardial structure and electrical activation pattern retains most of the in situ ventricular characteristics.

  19. Discrete series of unitary irreducible representations of the U{sub q}(u(3, 1)) and U{sub q}(u(n, 1)) noncompact quantum algebras

    SciTech Connect

    Smirnov, Yu. F.; Asherova, R. M.

    2011-06-15

    The structure of all discrete series of unitary irreducible representations of the U{sub q}(u(3, 1)) and U{sub q}(u(n, 1)) noncompact quantum algebras are investigated with the aid of extremal projection operators and the q-analog of the Mickelsson-Zhelobenko algebra Z(g, g Prime ){sub q}. The orthonormal basis constructed in the infinite-dimensional space of irreducible representations of the U{sub q}(u(n, 1)) Superset-Of-Or-Equal-To U{sub q}(u(n)) algebra is the q-analog of the Gelfand-Graev basis in the space of the corresponding irreducible representations of the u(n, 1) Superset-Of-Or-Equal-To u(n) classical algebra.

  20. Ventricular fibrillation following autologous intramyocardial cell therapy for inherited cardiomyopathy.

    PubMed

    Pytel, Peter; Husain, Aliya; Moskowitz, Ivan; Raman, Jai; MacLeod, Heather; Anderson, Allen S; Burke, Martin; McNally, Elizabeth M

    2010-01-01

    A 41-year-old male with cardiomyopathy from an inherited beta myosin heavy-chain mutation underwent treatment for heart failure with intramyocardial cell transplantation. He received direct injections into his heart of autologous precursor cells isolated from his blood. He immediately suffered ventricular fibrillation. Although he was resuscitated, he experienced a prolonged downward course that prohibited his undergoing transplantation. His autopsy revealed marked fibrosis throughout the myocardium with areas of mononuclear cell infiltrate. This case highlights the potential adverse effects associated with intramyocardial therapy in the cardiomyopathic heart.

  1. Ventricular fibrillation following autologous intramyocardial cell therapy for inherited cardiomyopathy

    PubMed Central

    Pytel, Peter; Husain, Aliya; Moskowitz, Ivan; Raman, Jai; MacLeod, Heather; Anderson, Allen S.; Burke, Martin; McNally, Elizabeth M.

    2010-01-01

    A 41 year old male with cardiomyopathy from an inherited β myosin heavy chain mutation underwent treatment for heart failure with intramyocardial cell transplantation. He received direct injections into his heart of autologous precursor cells isolated from his blood. He immediately suffered ventricular fibrillation. Although he was resuscitated, he experienced a prolonged downward course that prohibited his undergoing transplantation. His autopsy revealed marked fibrosis throughout the myocardium with areas of mononuclear cell infiltrate. This case highlights the potential adverse effects associated with intramyocardial therapy in the cardiomyopathic heart. PMID:19026577

  2. Failure of aneurysmectomy to improve left ventricular function.

    PubMed Central

    Sesto, M; Schwarz, F; Thiedemann, K U; Flameng, W; Schlepper, M

    1979-01-01

    Biplane left ventricular angiography was performed in 22 patients with isolated obstructive disease of the anterior descending branch of the left coronary artery and with an anterior aneurysm following transmural myocardial infarction. Six patients were restudied between 6 and 10 months after aneurysmectomy. Left ventricular reserve was estimated by analysis of a spontaneous postextrasystolic beat. Using angiographic techniques a contractile section, a transitional section, and a noncontractile section were identified. From the surgical patients the excised aneurysm and a transmural needle biopsy of the transitional section were investigated by light microscopy. With increasing volumes of noncontractile and transitional sections, total end-diastolic volume (r = 0.81, P less than 0.001) and end-systolic volume (r = 0.94, P less than 0.001) increased linearly, while the ejection fraction decreased (r = 0.70, P less than 0.001). No relation was found between the combined volumes of the noncontractile and transitional sections on the one hand, and the end-diastolic volume, the end-systolic volume, or the ejection fraction of the contractile section on the other hand. After aneurysmectomy a significant decrease was found in end-diastolic volume (194 to 133 ml/m2, P less than 0.001) and end-systolic volume (124 to 83 ml/m2, P less than 0.001) but no change occurred in ejection fraction (35 to 37%) and left ventricular end-diastolic pressure (23 to 25 mmHg). Surgical resection included part of the transitional section, which before surgery had an average ejection fraction of 27 per cent during a normal beat, rising to 41 per cent in a postextrasystolic beat. The transitional section after surgery now formed a large akinetic area of the anterior wall. We conclude that aneurysmectomy in isolated left anterior descending artery disease with anterior aneurysm fails to improve left ventricular function because the effect of reduction of left ventricular volumes is offset by

  3. Intracellular Ca(2+) dynamics and the stability of ventricular tachycardia.

    PubMed Central

    Chudin, E; Goldhaber, J; Garfinkel, A; Weiss, J; Kogan, B

    1999-01-01

    Ventricular fibrillation (VF), the major cause of sudden cardiac death, is typically preceded by ventricular tachycardia (VT), but the mechanisms underlying the transition from VT to VF are poorly understood. Intracellular Ca(2+) overload occurs during rapid heart rates typical of VT and is also known to promote arrhythmias. We therefore studied the role of intracellular Ca(2+) dynamics in the transition from VT to VF, using a combined experimental and mathematical modeling approach. Our results show that 1) rapid pacing of rabbit ventricular myocytes at 35 degrees C led to increased intracellular Ca(2+) levels and complex patterns of action potential (AP) configuration and the intracellular Ca(2+) transients; 2) the complex patterns of the Ca(2+) transient arose directly from the dynamics of intracellular Ca(2+) cycling, and were not merely passive responses to beat-to-beat alterations in AP; 3) the complex Ca(2+) dynamics were simulated in a modified version of the Luo-Rudy (LR) ventricular action potential with improved intracellular Ca(2+) dynamics, and showed good agreement with the experimental findings in isolated myocytes; and 4) when incorporated into simulated two-dimensional cardiac tissue, this action potential model produced a form of spiral wave breakup from VT to a VF-like state in which intracellular Ca(2+) dynamics played a key role through its influence on Ca(2+)-sensitive membrane currents such as I(Ca), I(NaCa), and I(ns(Ca)). To the extent that spiral wave breakup is useful as a model for the transition from VT to VF, these findings suggest that intracellular Ca(2+) dynamics may play an important role in the destabilization of VT and its degeneration into VF. PMID:10585917

  4. An Unusual Etiology for Bidirectional Ventricular Tachycardia.

    PubMed

    Zhao, Yun-Tao; Wang, Lei; Yi, Zhong

    2016-03-01

    Bidirectional ventricular tachycardia is a rare variety of tachycardia with a morphologically distinct presentation. The QRS axis and/or morphology alternate in the frontal plane leads. We report a patient with bidirectional ventricular tachycardia in association with aconitine poisoning. PMID:26604120

  5. Bidirectional ventricular tachycardia of unusual etiology

    PubMed Central

    Chakraborty, Praloy; Kaul, Bhavna; Mandal, Kausik; Isser, H.S.; Bansal, Sandeep; Subramanian, Anandaraja

    2016-01-01

    Bidirectional ventricular tachycardia (BDVT) is a rare form of ventricular arrhythmia, characterized by changing QRS axis of 180 degrees. Digitalis toxicity is considered as commonest cause of BDVT; other causes include aconite toxicity, myocarditis, myocardial infarction, metastatic cardiac tumour and cardiac channelopathies. We describe a case of BDVT in a patient with Anderson-Tawil syndrome. PMID:27479206

  6. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  7. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  8. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  9. Ventricular candidiasis in stone curlews (Burhinus oedicnemus).

    PubMed

    Caliendo, Valentina; Bull, Andrew

    2011-09-01

    Ventricular candidiasis is consistently one of the most prominent pathologic conditions diagnosed in stone curlews (Burhinus oedicnemus) in the United Arab Emirates, predominately affecting the captive population. Predisposing factors are a humid environment, stress, immunosuppression, inadequate nutrition, and an extended use of oral antibiotics. In this report, we describe the clinical signs, diagnosis, and pathologic result in stone curlews with ventricular candidiasis.

  10. Ventricular fibrillation coinciding with phentermine initiation.

    PubMed

    Tobbia, Patrick; Norris, Leslie A; Klima, Lawrence D

    2012-01-01

    A 70-year-old woman developed ventricular fibrillation subsequent to initiation of phentermine therapy. She was hospitalised and experienced recurrent ventricular fibrillation. During cardiac catheterisation, she was found to have a right coronary artery vasospasm, which resolved with intravenous nitroglycerin. Her phentermine was discontinued and the patient remained symptom free at last follow-up. PMID:23076689

  11. Ventricular-Fold Dynamics in Human Phonation

    ERIC Educational Resources Information Center

    Bailly, Lucie; Bernardoni, Nathalie Henrich; Müller, Frank; Rohlfs, Anna-Katharina; Hess, Markus

    2014-01-01

    Purpose: In this study, the authors aimed (a) to provide a classification of the ventricular-fold dynamics during voicing, (b) to study the aerodynamic impact of these motions on vocal-fold vibrations, and (c) to assess whether ventricular-fold oscillations could be sustained by aerodynamic coupling with the vocal folds. Method: A 72-sample…

  12. What Is a Ventricular Assist Device?

    MedlinePlus

    ... basic types of VADs are a left ventricular assist device (LVAD) and a right ventricular assist device (RVAD). If both types are used at the same time, they're called a biventricular assist device (BIVAD). The LVAD is the most common type of VAD. It ...

  13. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  14. 21 CFR 882.4060 - Ventricular cannula.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular cannula. 882.4060 Section 882.4060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  15. Circulatory support for right ventricular dysfunction.

    PubMed

    Jett, G K; Picone, A L; Clark, R E

    1987-07-01

    New modes of circulatory support for right ventricular dysfunction have recently been described. The present study compared the effectiveness of pulmonary artery balloon counterpulsation with a right ventricular assist device for support of surgically induced right ventricular dysfunction. Right ventricular hypertrophy was created in 16 neonatal lambs by pulmonary artery banding. Right ventricular dysfunction was produced in all animals by performing a right ventriculotomy and maintaining the pulmonary artery band. Four unassisted animals developed severe acute right heart failure and died. Six sheep had pulmonary artery balloon counterpulsation with a Dacron graft anastomosed to the proximal pulmonary artery as a reservoir for a 40 ml intra-aortic balloon after the onset of heart failure. The remaining six sheep had a pneumatically activated ventricular assist device inserted between the proximal pulmonary artery and the right ventricular apex. Periods of circulatory support with the balloon pump and the assist device on and off were compared. Decreases in right atrial pressure were observed with both balloon counterpulsation and right ventricular assistance: 14 +/- 1 to 11 +/- 1 mm Hg, p less than 0.0001, versus 19 +/- 2 to 12 +/- 2 mm Hg, p less than 0.0002, respectively. Cardiac output increased with both balloon counterpulsation and ventricular assistance: 1.45 +/- 0.16 to 2.03 +/- 0.13 L/min, p less than 0.001, versus 0.72 +/- 0.15 to 2.24 +/- 0.23 L/min, p less than 0.0002, respectively. Aortic systolic pressure increased in both support groups: 78 +/- 7 to 99 +/- 6 mm Hg, p less than 0.0004, versus 53 +/- 9 to 85 +/- 9 mm Hg, p less than 0.0001, respectively. Ventricular assistance produced greater changes in the right atrial pressure (39% +/- 6% versus 17% +/- 3%, p less than 0.01), cardiac output (153% +/- 39% versus 54% +/- 11%, p less than 0.05), and aortic systolic pressure (85% +/- 13% versus 39% +/- 9%, p less than 0.01). The insertion of a right

  16. Giant and thrombosed left ventricular aneurysm.

    PubMed

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  17. Arrhythmogenic right ventricular cardiomyopathy in two cats.

    PubMed

    Harvey, A M; Battersby, I A; Faena, M; Fews, D; Darke, P G G; Ferasin, L

    2005-03-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disease characterised by infiltration of the myocardium by adipose and fibrous tissue. The disease is an important cause of sudden death in humans, but has rarely been described in animals. This report describes ARVC in two cats with right-sided congestive heart failure. One cat had also experienced previous episodes of syncope. Standard six-lead and 24-hour (Holter) electrocardiogram recording revealed complete atrioventricular block and multiform ventricular ectopics in both cats, with the addition of ventricular tachycardia, ventricular bigeminy and R-on-T phenomenon in one of them. On echocardiography, the right ventricle and atrium were massively dilated and hypokinetic. The survival times of the cats were three days and 16 days following diagnosis. Histopathology in one case revealed fibro-fatty infiltration of the myocardium, predominantly affecting the right ventricular free wall. PMID:15789811

  18. Giant and thrombosed left ventricular aneurysm

    PubMed Central

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-01-01

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention. PMID:26225205

  19. Giant and thrombosed left ventricular aneurysm.

    PubMed

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention. PMID:26225205

  20. Coronary haemodynamics in left ventricular hypertrophy.

    PubMed Central

    Wallbridge, D. R.; Cobbe, S. M.

    1996-01-01

    BACKGROUND: Left ventricular hypertrophy is associated with an increased risk of cardiovascular morbidity and mortality. Previous studies have shown that patients with left ventricular hypertrophy develop electrocardiographic changes and left ventricular dysfunction during acute hypotension, and suggest that the lower end of autoregulation may be shifted upwards. AIM: To measure coronary blood flow (velocity) and flow reserve during acute hypotension in patients with left ventricular hypertrophy. PATIENTS: Eight patients with atypical chest pain and seven with hypertensive left ventricular hypertrophy; all with angiographically normal epicardial vessels. SETTING: Tertiary referral centre. METHODS: The physiological range of blood pressure was determined by previous ambulatory monitoring. Left ventricular mass was determined by echocardiography. At cardiac catheterisation, left coronary blood flow velocity was measured using a Judkins style Doppler tipped catheter. During acute hypotension with sodium nitroprusside, coronary blood flow velocity was recorded at rest and during maximal hyperaemia induced by intracoronary injection of adenosine. Quantitative coronary angiography was performed manually. RESULTS: For both groups coronary blood flow velocity remained relatively constant over a range of physiological diastolic blood pressures and showed a steep relation with diastolic blood pressure during maximal hyperaemia with intracoronary adenosine. Absolute coronary blood flow (calculated from quantitative angiographic data), standardised for left ventricular mass, showed reduced flow in the hypertensive group at rest and during maximal vasodilatation. CONCLUSION: The results are consistent with an inadequate blood supply to the hypertrophied heart, but no upward shift of the lower end of the autoregulatory range was observed. PMID:8705764

  1. Conquering the third ventricular chamber.

    PubMed

    Cohen-Gadol, Aaron A; Geryk, Bruce; Binder, Devin K; Tubbs, R Shane

    2009-09-01

    Surgery within the third ventricle was a special challenge early in the conception of the discipline of neurosurgery due to a lack of diagnostic methods and difficulty in reaching and removing lesions affecting this vital region. Walter Dandy and Harvey Cushing performed pioneering approaches of the third ventricular region. The authors have reviewed the previously undisclosed efforts of Cushing to approach the third ventricle through a direct review of his available patient records at the Cushing Brain Tumor Registry. The authors compare these efforts to those of Dandy published in Dandy's pioneering work Benign Tumors in the Third Ventricle of the Brain: Diagnosis and Treatment. Based on the review of these records, the authors attempt to examine the foundations of surgery within the third ventricle. PMID:19361257

  2. Self-inflicted ventricular septal defect

    PubMed Central

    Leaver, D. G.; Sharma, R. N.; Glennie, J. S.

    1970-01-01

    A case of attempted suicide is described which is believed to be the first reported example of survival after a self-inflicted penetrating knife wound of the heart. The 12 cm. blade entered the right ventricle and damaged one of the papillary muscles. The ventricular septum was also perforated. At cardiotomy the stab wound in the free wall of the right ventricle was surtured and the papillary muscle repaired. The ventricular septal defect was closed, but a small left-to-right shunt at ventricular level reappeared after operation. Images PMID:5433343

  3. Calcium-activated potassium current modulates ventricular repolarization in chronic heart failure.

    PubMed

    Bonilla, Ingrid M; Long, Victor P; Vargas-Pinto, Pedro; Wright, Patrick; Belevych, Andriy; Lou, Qing; Mowrey, Kent; Yoo, Jae; Binkley, Philip F; Fedorov, Vadim V; Györke, Sandor; Janssen, Paulus M L; Kilic, Ahmet; Mohler, Peter J; Carnes, Cynthia A

    2014-01-01

    The role of I(KCa) in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of I(KCa) blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The I(KCa) blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by I(KCa) blockade in all of the groups studied. I(KCa) blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. I(KCa) blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, I(KCa) blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for I(KCa) in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles.

  4. Management of Ventricular Arrhythmias in Patients with Mechanical Ventricular Support Devices.

    PubMed

    Healy, Chris; Viles-Gonzalez, Juan F; Sacher, Frederic; Coffey, James O; d'Avila, Andre

    2015-08-01

    The use of mechanical ventricular support devices in the management of patients with advanced heart failure continues to increase. These devices have been shown to prolong life as a destination therapy and to increase survival when used as a bridge to transplantation. However, they are associated with a high rate of complications, including bleeding, infection, device malfunction, and ventricular arrhythmias (VAs). The mechanical support provided by the device typically allows for VAs to be well tolerated in the acute setting, though there are numerous long-term complications related to VAs such as ventricular remodeling, right ventricular failure in patients with left ventricular assist devices, and possibly increased mortality. Controversy exists as to the appropriate role of implantable cardioverter defibrillators in these patients. This review will focus on the management options available for patients with mechanical ventricular support devices and VAs. PMID:26072439

  5. Polymorphic Ventricular Tachycardia/Ventricular Fibrillation and Sudden Cardiac Death in the Normal Heart.

    PubMed

    Shah, Ashok J; Hocini, Meleze; Denis, Arnaud; Derval, Nicolas; Sacher, Frederic; Jais, Pierre; Haissaguerre, Michel

    2016-09-01

    Primary electrical diseases manifest with polymorphic ventricular tachycardia (PMVT) and ventricular fibrillation (VF) and along with idiopathic VF contribute to about 10% of sudden cardiac deaths (SCDs) overall. These disorders include long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, short QT syndrome, and early repolarization syndrome. This article reviews the clinical electrophysiological management of PMVT/VF in a structurally normal heart affected with these disorders. PMID:27521091

  6. Effect of Transmurally Heterogeneous Myocyte Excitation-Contraction Coupling on Left Ventricular Electromechanics

    PubMed Central

    Campbell, Stuart G.; Howard, Elliot; Aguado-Sierra, Jazmin; Coppola, Benjamin A.; Omens, Jeffrey H.; Mulligan, Lawrence J.; McCulloch, Andrew D.; Kerckhoffs, Roy CP

    2009-01-01

    The excitation-contraction coupling properties of cardiac myocytes isolated from different regions of the mammalian left ventricular wall have been shown to vary considerably, with uncertain effects on ventricular function. We embedded a cell-level excitation-contraction coupling model with region-dependent parameters within a simple finite element model of left ventricular geometry to study effects of electromechanical heterogeneity on local myocardial mechanics and global hemodynamics. This model was compared with one in which heterogeneous myocyte parameters were assigned randomly throughout the mesh while preserving the total amount of each cell subtype. The two models displayed nearly identical transmural patterns of fibre and cross-fibre strains at end systole, but showed clear differences in fibre strains at earlier points during systole. Hemodynamic function, including peak left ventricular pressure, maximum rate of left ventricular pressure development, and stroke volume were essentially identical in the two models. These results suggest that in the intact ventricle heterogeneously distributed myocyte subtypes primarily impact local deformation of the myocardium, and that these effects are greatest during early systole. PMID:19251984

  7. Arrhythmogenic ventricular cardiomyopathy: A paradigm shift from right to biventricular disease

    PubMed Central

    Saguner, Ardan M; Brunckhorst, Corinna; Duru, Firat

    2014-01-01

    Arrhythmogenic ventricular cardiomyopathy (AVC) is generally referred to as arrhythmogenic right ventricular (RV) cardiomyopathy/dysplasia and constitutes an inherited cardiomyopathy. Affected patients may succumb to sudden cardiac death (SCD), ventricular tachyarrhythmias (VTA) and heart failure. Genetic studies have identified causative mutations in genes encoding proteins of the intercalated disk that lead to reduced myocardial electro-mechanical stability. The term arrhythmogenic RV cardiomyopathy is somewhat misleading as biventricular involvement or isolated left ventricular (LV) involvement may be present and thus a broader term such as AVC should be preferred. The diagnosis is established on a point score basis according to the revised 2010 task force criteria utilizing imaging modalities, demonstrating fibrous replacement through biopsy, electrocardiographic abnormalities, ventricular arrhythmias and a positive family history including identification of genetic mutations. Although several risk factors for SCD such as previous cardiac arrest, syncope, documented VTA, severe RV/LV dysfunction and young age at manifestation have been identified, risk stratification still needs improvement, especially in asymptomatic family members. Particularly, the role of genetic testing and environmental factors has to be further elucidated. Therapeutic interventions include restriction from physical exercise, beta-blockers, sotalol, amiodarone, implantable cardioverter-defibrillators and catheter ablation. Life-long follow-up is warranted in symptomatic patients, but also asymptomatic carriers of pathogenic mutations. PMID:24772256

  8. Left ventricular function in patients with ventricular arrhythmias and aortic valve disease

    SciTech Connect

    Santinga, J.T.; Kirsh, M.M.; Brady, T.J.; Thrall, J.; Pitt, B.

    1983-02-01

    Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease.

  9. Rest and exercise ventricular function in adults with congenital ventricular septal defects

    SciTech Connect

    Jablonsky, G.; Hilton, J.D.; Liu, P.P.; Morch, J.E.; Druck, M.N.; Bar-Shlomo, B.Z.; McLaughlin, P.R.

    1983-01-15

    Rest and exercise right and left ventricular function were compared using equilibrium gated radionuclide angiography in 19 normal sedentary control subjects and 34 patients with hemodynamically documented congenital ventricular septal defect (VSD). Gated radionuclide angiography was performed at rest and during each level of graded supine bicycle exercise to fatigue. Heart rate, blood pressure, maximal work load achieved, and right and left ventricular ejection fractions were assessed. The control subjects demonstrated an increase in both the left and right ventricular ejection fractions with exercise. All study groups failed to demonstrate an increase in ejection fraction in either ventricle with exercise. Furthermore, resting left ventricular ejection fraction in Groups 2 and 3 was lower than that in the control subjects and resting right ventricular ejection fraction was lower in Group 3 versus control subjects. Thus left and right ventricular function on exercise were abnormal in patients with residual VSD as compared with control subjects; rest and exercise left ventricular ejection fractions remained abnormal despite surgical closure of VSD in the remote past; resting left and right ventricular function was abnormal in patients with Eisenmenger's complex; lifelong volume overload may be detrimental to myocardial function.

  10. Local regional stimulation of single isolated ventricular myocytes using microfluidics.

    PubMed

    Klauke, Norbert; Smith, Godfrey; Cooper, Jonathan M

    2009-08-01

    The regional manipulation of the microenvironment surrounding single adult cardiac myocytes in a microfluidic structure is described. The flow rates of laminar streams were adjusted such that the fluid interface between an injection flow and a perfusion flow was manipulated laterally to stimulate regions of the cell surface. Using this general principle, we were able to selectively expose defined regions of the cell to test solutions, with predefined pulse durations and frequencies. We demonstrate the transient depolarisation of the cardiomyocyte through the regional chemical stimulation of localized areas of the cell with elevated potassium concentrations (100 mM). The results show that chemical stimulation at frequencies < or = 0.25 Hz evoked Ca(2+) transients and cell shortening, comparable to those induced by electrical (field) stimulation. At higher frequencies the membrane potential failed to recover sufficiently from the depolarisation with the high K(+) solution, possibly because of the slow clearance of the ion from the t-tubular system. To test this hypothesis, the clearance of fluorescently labeled 10 kDa dextran from the t-system was measured and found to be approximately 0.5 s delayed compared to that of the bulk extracellular space, indicating the slow diffusion inside the confined space of the tubular membrane invaginations.

  11. Sequential Notch activation regulates ventricular chamber development

    PubMed Central

    D'Amato, Gaetano; Luxán, Guillermo; del Monte-Nieto, Gonzalo; Martínez-Poveda, Beatriz; Torroja, Carlos; Walter, Wencke; Bochter, Matthew S.; Benedito, Rui; Cole, Susan; Martinez, Fernando; Hadjantonakis, Anna-Katerina; Uemura, Akiyoshi; Jiménez-Borreguero, Luis J.; de la Pompa, José Luis

    2016-01-01

    Ventricular chambers are essential for the rhythmic contraction and relaxation occurring in every heartbeat throughout life. Congenital abnormalities in ventricular chamber formation cause severe human heart defects. How the early trabecular meshwork of myocardial fibres forms and subsequently develops into mature chambers is poorly understood. We show that Notch signalling first connects chamber endocardium and myocardium to sustain trabeculation, and later coordinates ventricular patterning and compaction with coronary vessel development to generate the mature chamber, through a temporal sequence of ligand signalling determined by the glycosyltransferase manic fringe (MFng). Early endocardial expression of MFng promotes Dll4–Notch1 signalling, which induces trabeculation in the developing ventricle. Ventricular maturation and compaction require MFng and Dll4 downregulation in the endocardium, which allows myocardial Jag1 and Jag2 signalling to Notch1 in this tissue. Perturbation of this signalling equilibrium severely disrupts heart chamber formation. Our results open a new research avenue into the pathogenesis of cardiomyopathies. PMID:26641715

  12. Idiopathic left ventricular hypertrophy in an infant.

    PubMed

    Bhardwaj, Rajeev; Bhardwaj, Praveen

    2011-01-01

    Cardiac hypertrophy in infancy has been a subject of considerable interest. We present a case of significant left ventricular hypertrophy without any associated cause, presenting in infancy. PMID:23550435

  13. Ventricular repolarization measures for arrhythmic risk stratification

    PubMed Central

    Monitillo, Francesco; Leone, Marta; Rizzo, Caterina; Passantino, Andrea; Iacoviello, Massimo

    2016-01-01

    Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave (QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice. PMID:26839657

  14. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  15. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  16. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  17. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  18. 21 CFR 882.4100 - Ventricular catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for injection of material into, or removal of material from, the brain. (b) Classification. Class II...

  19. Cardiac sarcoidosis mimicking right ventricular dysplasia.

    PubMed

    Shiraishi, Jun; Tatsumi, Tetsuya; Shimoo, Kazutoshi; Katsume, Asako; Mani, Hiroki; Kobara, Miyuki; Shirayama, Takeshi; Azuma, Akihiro; Nakagawa, Masao

    2003-02-01

    A 59-year-old woman with skin sarcoidosis was admitted to hospital for assessment of complete atrioventricular block. Cross-sectional echocardiography showed that the apical free wall of the right ventricle was thin and dyskinetic with dilation of the right ventricle. Thallium-201 myocardial imaging revealed a normal distribution. Both gallium-67 and technetium-99m pyrophosphate scintigraphy revealed no abnormal uptake in the myocardium. Right ventriculography showed chamber dilation and dyskinesis of the apical free wall, whereas left ventriculography showed normokinesis, mimicking right ventricular dysplasia. Cardiac sarcoidosis was diagnosed on examination of an endomyocardial biopsy specimen from the right ventricle. A permanent pacemaker was implanted to manage the complete atrioventricular block. After steroid treatment, electrocardiography showed first-degree atrioventricular block and echocardiography revealed an improvement in the right ventricular chamber dilation. Reports of cardiac sarcoidosis mimicking right ventricular dysplasia are extremely rare and as this case shows, right ventricular involvement may be one of its manifestations.

  20. Premature Ventricular Complexes and Premature Ventricular Complex Induced Cardiomyopathy.

    PubMed

    Latchamsetty, Rakesh; Bogun, Frank

    2015-09-01

    Presentation, prognosis, and management of premature ventricular complexes (PVCs) vary significantly among patients and depend on PVC characteristics as well as patient comorbidities. Presentation can range from incidental discovery in an asymptomatic patient to debilitating heart failure. Prognosis depends on, among other factors, the presence or absence of structural heart disease, PVC burden and other factors detailed in this review. Our understanding of the clinical significance of frequent PVCs, particularly as it relates to development of cardiomyopathy, has advanced greatly in the past decade. In this article, we explore the mechanisms governing PVC initiation and discuss prevalence and frequency of PVCs in the general population. We also explore prognostic implications based on PVC frequency as well as the presence or absence of underlying heart disease. We then take a focused look at PVC-induced cardiomyopathy and identify predictors for developing cardiomyopathy. Finally, we discuss clinical evaluation and management of patients presenting with frequent PVCs. Management can include clinical observation, addressing reversible causes, lifestyle modification, pharmacotherapy, or catheter ablation.

  1. Ventricular restoration--a surgical approach to reverse ventricular remodeling.

    PubMed

    Buckberg, Gerald D

    2004-10-01

    Congestive heart failure is most often caused by scar from coronary occlusion. The transition from occluded vessel to scar to dilation results in a remodeled ventricle that changes shape from ellipse to sphere. This shape change following an index event is called remodeling and a surgical approach for restoration (bring back to normal) will be described that uses the patient's own tissue, rather than employing heart replacement by mechanical devices or transplantation. The surgical restoration approach was taken by the RESTORE group that comprises an international medical and surgical team that will report (a) the remodeling infrastructure, role of compensatory remote muscle, and factors underlying surgical restoration decisions, (b) structural basis for ventricular geometric changes and surgical background for restoration, (c) individual rebuilding experience in 1150 patients over 20 years from one center, (d) integrated 5 year results from the RESTORE team in 1198 patients, (e) electrical aspects of restoration in 382 patients with only one AICD used, (f) how restoration improves mechanical synchrony without electrical devices, (g) geometric reasons for secondary mitral insufficiency and impact of adding mitral repair during SVR procedures, and (h) importance of defining site specific scar in no ischemic disease to identify a similar trigger lesion in non ischemic cardiomyopathy. The importance of a team approach by the RESTORE group may set the benchmark for collaborative world wide groups, and thereby depart from traditional focal approaches by individual disciplines. PMID:15886970

  2. Right ventricular false tendons, a cadaveric approach.

    PubMed

    Loukas, Marios; Wartmann, Christopher T; Tubbs, R Shane; Apaydin, Nihal; Louis, Robert G; Black, Brandie; Jordan, Robert

    2008-06-01

    Left ventricular false tendons (LFTs) have been extensively described and recognized by gross anatomic studies. However, there is very little information available regarding right ventricular false tendons (RFTs). The aim of our study, therefore, was to explore and delineate the morphology, topography and morphometry of the RFTs, and provide a comprehensive picture of their anatomy across a broad range of specimens. We identified 35/100 heart specimens containing right ventricular RFTs and classified them into five types. In Type I (21, 47.7%) the RFTs, was located between the ventricular septum and the anterior papillary muscle; in Type II (11, 22.9%) between ventricular septum and the posterior papillary muscle; in Type III (7, 14.5%) between the anterior leaflet of the tricuspid valve and the right ventricular free wall; in Type IV (5, 10.4%) between the posterior papillary muscle and the ventricular free wall; and lastly, in Type V (4, 8.3%) between the anterior papillary muscle and ventricular free wall. The mean length of the RFTs was 18 +/- 7 mm with a mean diameter of 1.4 +/- 05 mm. Histologic examination with Masson trichrome and PAS revealed that 20 (41.6%) of the 48 RFTs carried conduction tissue fibers. The presence of conduction tissue fibers within the RFTs was limited to Types I, III, and IV. In Types II and V the RFTs resembled fibrous structures in contrast with Type I, II and IV, which were composed more of muscular fibers, including conduction tissue fibers. RFTs containing conduction tissue fibers were identified, which may implicate them in the appearance of arrhythmias.

  3. Ventricular Septal Defect from Takotsubo Syndrome

    PubMed Central

    Caplow, Julie; Quatromoni, Neha

    2016-01-01

    Takotsubo Syndrome is a transient condition characterized by left ventricular systolic dysfunction with apical akinesis/dyskinesis and ballooning. Although the prognosis with medical management is excellent in most cases, rare cases of serious complications can occur. We present here a case of a 71-year-old woman presenting with acute decompensated heart failure with initial findings consistent with a myocardial infarction, who was found instead to have an acute ventricular septal defect as a complication of Takotsubo Syndrome. PMID:27563471

  4. [Ventricular contractility: Physiology and clinical projection].

    PubMed

    Domenech, Raúl J; Parra, Víctor M

    2016-06-01

    The contractile state of the heart is the result of myocardial contractility, the intrinsic mechanism that regulates the force and the shortening of the ventricle and determines the ventricular ejection volume. However, the ejection volume is also modulated by ventricular preload (diastolic ventricular volume) and afterload (resistance to ejection). Accordingly, a decrease in contractility may be masked by changes in preload or afterload, maintaining a normal ejection volume and delaying the diagnosis of myocardial damage. Thus, it is necessary to develop a non-invasive method to measure contractility in the clinical practice. We review in this article the basic principles of cardiac contraction, the concept of contractility and its measurement with the ventricular pressure-volume loop, an experimental method that also measures most of the hemodynamic variables of the cardiac cycle including preload, afterload, ventricular work, ventricular lusitropy and arterial elastance. This method has been recently validated in cardiac patients and allows to evaluate the evolution of contractility in heart failure in a non invasive way. Although some modifications are still necessary, it will probably have an extensive use in practical cardiology in the near future. PMID:27598497

  5. Electrohydraulic ventricular assist device development.

    PubMed

    Diegel, P D; Mussivand, T; Holfert, J W; Juretich, J T; Miller, J A; Maclean, G K; Szurmak, Z; Santerre, J P; Rajagopalan, K; Dew, P A

    1992-01-01

    An electrohydraulic ventricular assist device has been developed. An axial flow pump driven by a brushless DC motor provides actuation. Energy is supplied by internal Ni/Cd batteries and by external Ag/Zn batteries, both rechargeable. Electromagnetic induction is used to pass energy through the skin with a transcutaneous energy transfer (TET) system. Physiologic control, battery management, motor commutation, and communication functions are performed by a surface mount internal controller. An infrared data link within the TET coils provides bidirectional communication between the external and internal controllers. A computer model was developed to predict system performance. The dimensions are 180 mm x 116 mm x 40 mm. An in vitro system pumped 5.7 L/min at 10 mmHg inflow and 100 mmHg outflow pressure. The internal battery can provide the projected energy requirements for 40 min after 540 charge/discharge cycles, and the external battery is capable of 4 hr of operation after 150 cycles. The TET system can deliver 60 W of power and exceeds 80% efficiency between 15 and 30 W. The device configuration is based on human cadaver and intraoperative fit trials. The device is being modified for calf implantation by redirecting the blood ports, increasing the output, and incorporating the internal controller in the unified device base. PMID:1457871

  6. Resveratrol reduces intracellular free calcium concentration in rat ventricular myocytes.

    PubMed

    Liu, Zheng; Zhang, Li-Ping; Ma, Hui-Jie; Wang, Chuan; Li, Ming; Wang, Qing-Shan

    2005-10-25

    Resveratrol (trans-3, 4', 5-trihydroxy stilbene), a phytoalexin found in grape skins and red wine, has been reported to have a wide range of biological and pharmacological properties. It has been speculated that resveratrol may have cardioprotective activity. The objective of our study was to investigate the effects of resveratrol on intracellular calcium concentration ([Ca(2+)](i)) in rat ventricular myocytes. [Ca(2+)](i) was detected by laser scanning confocal microscopy. The results showed that resveratrol (15~60 mumol/L) reduced [Ca(2+)](i) in normal and Ca(2+)-free Tyrode's solution in a concentration-dependent manner. The effects of resveratrol on [Ca(2+)](i) in normal Tyrode's solution was partially inhibited by pretreatment with sodium orthovanadate (Na3VO4, 1.0 mmol/L, P<0.01), an inhibitor of protein tyrosine phosphatase, or L-type Ca(2+) channel agonist Bay K8644 (10 mumol/L, P<0.05), but could not be antagonized by NO synthase inhibitor L-NAME (1.0 mmol/L). Resveratrol also markedly inhibited the ryanodine-induced [Ca(2+)](i) increase in Ca(2+)-free Tyrode's solution (P<0.01). When Ca(2+) waves were produced by increasing extracellular Ca(2+) concentration from 1 to 10 mmol/L, resveratrol (60 mumol/L) could reduce the velocity and duration of propagating waves, and block the propagating waves of elevated [Ca(2+)](i). These results suggest that resveratrol may reduce the [Ca(2+)](i) in isolated rat ventricular myocytes. The inhibition of voltage-dependent Ca(2+) channel and tyrosine kinase, and alleviation of Ca(2+) release from sarcoplasmic reticulum (SR) are possibly involved in the effects of resveratrol on rat ventricular myocytes. These findings could help explain the protective activity of resveratrol against cardiovascular disease. PMID:16220198

  7. Right ventricular volume analysis by angiography in right ventricular cardiomyopathy.

    PubMed

    Indik, Julia H; Dallas, William J; Gear, Kathleen; Tandri, Harikrishna; Bluemke, David A; Moukabary, Talal; Marcus, Frank I

    2012-06-01

    Imaging of the right ventricle (RV) for the diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is commonly performed by echocardiography or magnetic resonance imaging (MRI). Angiography is an alternative modality, particularly when MRI cannot be performed. We hypothesized that RV volume and ejection fraction computed by angiography would correlate with these quantities as computed by MRI. RV volumes and ejection fraction were computed for subjects enrolled in the North American ARVC/D Registry, with both RV angiography and MRI studies. Angiography was performed in the 30° right anterior oblique (RAO) and 60° left anterior oblique (LAO) views. Angiographic volumes were computed by RAO view and two-view (RAO and LAO) formulae. 17 subjects were analyzed (11 men and 6 women), with 15 subjects classified as affected, and two as unaffected by modified Task Force criteria. The correlation coefficient of MRI to the two-view angiographic analysis was 0.72 (P = 0.003) for end-diastolic volume and 0.68 (P = 0.005) for ejection fraction. Angiographically derived volumes were larger than MRI derived volume (P = 0.009) and with the slope in a linear relationship equal to 0.8 for end diastolic volume, and 0.9 for RV ejection fraction (P < 0.001), computed by the two view formula. End-diastolic volumes and ejection fractions of the RV obtained by dual view angiography correlate with these quantities by MRI. RV end-diastolic volumes are larger by RV angiography in comparison with MRI.

  8. Left ventricular function: time-varying elastance and left ventricular aortic coupling.

    PubMed

    Walley, Keith R

    2016-01-01

    Many aspects of left ventricular function are explained by considering ventricular pressure-volume characteristics. Contractility is best measured by the slope, Emax, of the end-systolic pressure-volume relationship. Ventricular systole is usefully characterized by a time-varying elastance (ΔP/ΔV). An extended area, the pressure-volume area, subtended by the ventricular pressure-volume loop (useful mechanical work) and the ESPVR (energy expended without mechanical work), is linearly related to myocardial oxygen consumption per beat. For energetically efficient systolic ejection ventricular elastance should be, and is, matched to aortic elastance. Without matching, the fraction of energy expended without mechanical work increases and energy is lost during ejection across the aortic valve. Ventricular function curves, derived from ventricular pressure-volume characteristics, interact with venous return curves to regulate cardiac output. Thus, consideration of ventricular pressure-volume relationships highlight features that allow the heart to efficiently respond to any demand for cardiac output and oxygen delivery. PMID:27613430

  9. Left ventricular oxygen consumption and organ blood flow distribution during pulsatile ventricular assist.

    PubMed

    Pantalos, G M; Marks, J D; Riebman, J B; Everett, S D; Burns, G L; Burton, N A; DePaulis, R

    1988-01-01

    One goal of left ventricular assistance is the reduction of left ventricular myocardial oxygen consumption while delivering adequate organ blood flow. The effect of assist device operation control mode and uptake cannulation method on the achievement of this goal was studied in six acutely prepared calves with healthy hearts. All combinations of left ventricular assistance significantly reduced the myocardial oxygen consumption; the reduction was independent of control mode. During ventricular assistance, regional organ blood flow distribution and myocardial endocardial/epicardial blood flow ratio were not different from values during the control, unassisted condition. Regardless of the left ventricular assist device uptake method or operational control mode, significant reduction in myocardial oxygen consumption was achieved while maintaining organ blood flow distribution.

  10. Significance of Late Gadolinium Enhancement at Right Ventricular Attachment to Ventricular Septum in Patients With Hypertrophic Cardiomyopathy.

    PubMed

    Chan, Raymond H; Maron, Barry J; Olivotto, Iacopo; Assenza, Gabriele E; Haas, Tammy S; Lesser, John R; Gruner, Christiane; Crean, Andrew M; Rakowski, Harry; Rowin, Ethan; Udelson, James; Lombardi, Massimo; Tomberli, Benedetta; Spirito, Paolo; Formisano, Francesco; Marra, Martina P; Biagini, Elena; Autore, Camillo; Manning, Warren J; Appelbaum, Evan; Roberts, William C; Basso, Cristina; Maron, Martin S

    2015-08-01

    Cardiovascular magnetic resonance (CMR) with extensive late gadolinium enhancement (LGE) is a novel marker for increased risk for sudden death (SD) in patients with hypertrophic cardiomyopathy (HC). Small focal areas of LGE confined to the region of right ventricular (RV) insertion to ventricular septum (VS) have emerged as a frequent and highly visible CMR imaging pattern of uncertain significance. The aim of this study was to evaluate the prognostic significance of LGE confined to the RV insertion area in patients with HC. CMR was performed in 1,293 consecutive patients with HC from 7 HC centers, followed for 3.4 ± 1.7 years. Of 1,293 patients (47 ± 14 years), 134 (10%) had LGE present only in the anterior and/or inferior areas of the RV insertion to VS, occupying 3.7 ± 2.9% of left ventricular myocardium. Neither the presence nor extent of LGE in these isolated areas was a predictor of adverse HC-related risk, including SD (adjusted hazard ratio 0.82, 95% confidence interval 0.45 to 1.50, p = 0.53; adjusted hazard ratio 1.16/10% increase in LGE, 95% confidence interval 0.29 to 4.65, p = 0.83, respectively). Histopathology in 20 HC hearts show the insertion areas of RV attachment to be composed of a greatly expanded extracellular space characterized predominantly by interstitial-type fibrosis and interspersed disorganized myocyte patterns and architecture. In conclusion, LGE confined to the insertion areas of RV to VS was associated with low risk of adverse events (including SD). Gadolinium pooling in this region of the left ventricle does not reflect myocyte death and repair with replacement fibrosis or scarring.

  11. Modeling left ventricular diastolic dysfunction: classification and key indicators

    PubMed Central

    2011-01-01

    Background Mathematical modeling can be employed to overcome the practical difficulty of isolating the mechanisms responsible for clinical heart failure in the setting of normal left ventricular ejection fraction (HFNEF). In a human cardiovascular respiratory system (H-CRS) model we introduce three cases of left ventricular diastolic dysfunction (LVDD): (1) impaired left ventricular active relaxation (IR-type); (2) increased passive stiffness (restrictive or R-type); and (3) the combination of both (pseudo-normal or PN-type), to produce HFNEF. The effects of increasing systolic contractility are also considered. Model results showing ensuing heart failure and mechanisms involved are reported. Methods We employ our previously described H-CRS model with modified pulmonary compliances to better mimic normal pulmonary blood distribution. IR-type is modeled by changing the activation function of the left ventricle (LV), and R-type by increasing diastolic stiffness of the LV wall and septum. A 5th-order Cash-Karp Runge-Kutta numerical integration method solves the model differential equations. Results IR-type and R-type decrease LV stroke volume, cardiac output, ejection fraction (EF), and mean systemic arterial pressure. Heart rate, pulmonary pressures, pulmonary volumes, and pulmonary and systemic arterial-venous O2 and CO2 differences increase. IR-type decreases, but R-type increases the mitral E/A ratio. PN-type produces the well-described, pseudo-normal mitral inflow pattern. All three types of LVDD reduce right ventricular (RV) and LV EF, but the latter remains normal or near normal. Simulations show reduced EF is partly restored by an accompanying increase in systolic stiffness, a compensatory mechanism that may lead clinicians to miss the presence of HF if they only consider LVEF and other indices of LV function. Simulations using the H-CRS model indicate that changes in RV function might well be diagnostic. This study also highlights the importance of septal

  12. Modified Stumper technique for acute postoperative bifurcation stenosis causing right ventricular failure after Ross procedure

    PubMed Central

    Divekar, Abhay A

    2016-01-01

    In this report, we describe a 15-year-old patient who underwent a Ross procedure for a regurgitant bicuspid aortic valve and ascending aortic dilation. After the operation was over, he could not be separated from cardiopulmonary bypass and was noted to have isolated right ventricular failure. This report takes the reader through the diagnostic evaluation, highlights the importance of invasive assessment in the immediate postoperative period, and discusses successful transcatheter intervention in the acute postoperative setting.

  13. Modified Stumper technique for acute postoperative bifurcation stenosis causing right ventricular failure after Ross procedure

    PubMed Central

    Divekar, Abhay A

    2016-01-01

    In this report, we describe a 15-year-old patient who underwent a Ross procedure for a regurgitant bicuspid aortic valve and ascending aortic dilation. After the operation was over, he could not be separated from cardiopulmonary bypass and was noted to have isolated right ventricular failure. This report takes the reader through the diagnostic evaluation, highlights the importance of invasive assessment in the immediate postoperative period, and discusses successful transcatheter intervention in the acute postoperative setting. PMID:27625524

  14. Ventricular patch endocarditis caused by Propionibacterium acnes: advantages of gallium scanning.

    PubMed

    Vandenbos, F; Roger, P M; Mondain-Miton, V; Dunais, B; Fouché, R; Kreitmann, P; Carles, D; Migneco, O; Dellamonica, P

    2001-11-01

    Propionibacterium acnes is a weakly pathogenic commensal of the skin. When isolated from blood cultures it is often considered a contaminant. However, P. acnes may be responsible for severe infections and its role in certain cases of infectious endocarditis has now been definitely established.(1) We report a case of endocarditis due to P. acnes stemming from a ventricular patch and revealed by a gallium 67 scan. PMID:11869063

  15. Leptin decreases heart rate associated with increased ventricular repolarization via its receptor.

    PubMed

    Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H; Hull, Robert; Davis, Mary; Yu, Han-Gang

    2015-11-15

    Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 μg/kg) decreased resting heart rate; at high doses (150-300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias.

  16. Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia1

    PubMed Central

    Indik, Julia H; Marcus, Frank I

    2003-01-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is characterized by the patchy replacement of myocardium by fatty or fibrofatty tissue. These changes lead to structural abnormalities including right ventricular enlargement and wall motion abnormalities that can be detected by echocardiography, angiography, and cine MRI. ARVC/D is a genetically heterogeneous disorder, since it has been linked to several chromosomal loci. Myocarditis may also be a contributing etiological factor. Patients are typically diagnosed during adolescence or young adulthood. Presenting symptoms are generally related to ventricular arrhythmias. Concern for the risk of sudden cardiac death may lead to the implantation of an intracardiac defibrillator. An ongoing multicenter international registry should further our understanding of this disease. PMID:16943913

  17. Ventricular tachycardia following trans-apical aortic valve replacement.

    PubMed

    Beinart, Roy; Danik, Stephan; Palacios, Igor; Barrett, Conor; Inglessis, Ignacio; Agnihotri, Arvind; Passeri, Jonathan

    2012-03-01

    Transcatheter aortic valve replacement (TAVR) is a relatively new procedure for high-risk patients with severe aortic stenosis. We report a case of a new left ventricular outflow tract ventricular tachycardia following TAVR. PMID:22016303

  18. [Right ventricular myxoma. A rare case of pulmonary stenosis].

    PubMed

    Riera, J M; Vila, I C; Serrano, J M; Aleixandre, L M; Baliarda, X R; de Auta, G M; Ruiz, F E; Domenech, J P; Garriga, J R

    1996-02-01

    We discuss a case of a fourteen year old girl in whom, clinical signs of right ventricular outflow obstruction were discovered following a syncopal attack. A right ventricular tumor was observed by echocardiography. Histology confirmed the diagnosis of myxoma.

  19. Echocardiographic differentiation of atrioventricular septal defects from inlet ventricular septal defects and mitral valve clefts.

    PubMed

    Sulafa, Ali K M; Tamimi, Omer; Najm, Hani K; Godman, Michael J

    2005-03-01

    Left ventricular inlet/outlet ratio and percent left atrioventricular valve (AVV) guarded by the posterior leaflet are valuable for characterizing atrioventricular septal defect (AVSD). We performed these measurements echocardiographically in normal patients (n = 101), patients who had AVSD (n = 37), those who had isolated perimembranous inlet ventricular septal defect (VSD; n = 12), and those who had "isolated" mitral valve clefts (n = 5). Surgical findings of 38 patients were reviewed. The normal inlet/outlet ratio was 1.03 +/- 0.07. For patients who had AVSD, the ratio was 0.82 +/- 0.06 (95% confidence interval [CI] 0.180 to 0.237, p = 0.001). For patients who had an isolated inlet VSD, this ratio was lower than that in normal patients (0.93 +/- 0.08, 95% CI 034 to 0.116, p = 0.001) but higher than that in patients who had AVSD (95% CI -0.175 to 0.091, p = 0.001). The percent left AVV guarded by the posterior leaflet was 56 +/- 1.4 in normal patients. For patients who had AVSD, it was significantly lower (43 +/- 1.1). For patients who had an isolated VSD and those who had an isolated mitral cleft, it was normal (57 +/- 1.9 and 55 +/- 2.2, respectively). The 2 measurements are valuable in differentiating AVSD from inlet VSD and isolated mitral cleft, but percent left AVV guarded by the posterior leaflet is more specific.

  20. Right Ventricular Cardiomyopathy Meeting the Arrhythmogenic Right Ventricular Dysplasia Revised Criteria? Don't Forget Sarcoidosis!

    PubMed Central

    Vasaturo, Sabina; Ploeg, David E.; Buitrago, Guadalupe; Zeppenfeld, Katja; Veselic-Charvat, Maud

    2015-01-01

    A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland. PMID:25995699

  1. Cardiomyopathy induced by incessant fascicular ventricular tachycardia.

    PubMed

    Velázquez-Rodríguez, Enrique; Rodríguez-Piña, Horacio; Pacheco-Bouthillier, Alex; Deras-Mejía, Luz María

    2013-01-01

    A 12-year-old girl with symptoms of fatigue, decreased exercise tolerance and progressive dyspnea (New York Heart Association functional class III) with a possible diagnosis of dilated cardiomyopathy secondary to viral myocarditis. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, she was referred for electrophysiological study. The diagnosis was idiopathic left ventricular tachycardia involving the posterior fascicle of the left bundle branch. After successful treatment with radiofrequency catheter ablation guided by a Purkinje potential radiological and echocardiographic evaluation showed complete reversal of left ventricular function in the first 3 months and no recurrence of arrhythmia during 2 years of follow up.

  2. Mechanisms of transplant right ventricular dysfunction.

    PubMed Central

    Van Trigt, P; Bittner, H B; Kendall, S W; Milano, C A

    1995-01-01

    OBJECTIVE: Right ventricular (RV) dysfunction remains the leading cause of early mortality after cardiac transplantation. The effect of brain death and subsequent hypothermic cardioplegic arrest and storage on subsequent post-transplant right ventricular function was examined. SUMMARY BACKGROUND DATA: Right ventricular dysfunction in the donor heart usually is attributed to failure of the donor right ventricle to adapt to the sudden increase in afterload (pulmonary vascular resistance) in the recipient. Strategies to improve ventricular mechanics in the postoperative period are aimed at reducing pulmonary vascular resistance with vasodilators or augmenting right ventricular contractility with inotropic agents. Events occurring in the donor heart (brain death, hypothermic cardioplegic arrest, and storage) also may be directly related to post-transplant RV dysfunction. METHODS: A canine model of brain death and orthotopic cardiac transplantation was used. A dynamic pressure-volume analysis of RV mechanics was performed using micromanometers and sonomicrometric dimension transducers. Systolic function was assessed by measurement of preload recruitable stroke work (PRSW). Brain death was induced in 17 dogs by inflation of an intracranial balloon. Right ventricular function then was assessed serially to 6 hours (PRSW). Right ventricular adrenergic beta receptor density and function was sampled at control and after 6 hours of brain death. The effect of cardioplegic arrest and hypothermic storage was assessed in a second group of 17 dogs, using the same instrumentation and method of RV analysis. RESULTS: A significant decrease in right ventricular PRSW occurred after brain death, with the average decrease being 37% +/- 10.4% from the control. The RV myocardial beta adrenergic receptor density did not significantly change (253 +/- 34 fmol/ng control vs. 336 +/- 54 fmol/ng after brain death). The adenylyl cyclase activity of the RV beta receptor was assessed and was not

  3. Premature Ventricular Complexes in Apparently Normal Hearts.

    PubMed

    Luebbert, Jeffrey; Auberson, Denise; Marchlinski, Francis

    2016-09-01

    Premature ventricular complexes (PVCs) are consistently associated with worse prognosis and higher morbidity and mortality. This article reviews PVCs and their presentation in patients with an apparently normal heart. Patients with PVCs may be completely asymptomatic, whereas others may note severely disabling symptoms. Cardiomyopathy may occur with frequent PVCs. Diagnostic work-up is directed at obtaining 12-lead ECG to characterize QRS morphology, Holter monitor to assess frequency, and echo and advanced imaging to assess for early cardiomyopathy and exclude structural heart disease. Options for management include watchful waiting, medical therapy, or catheter ablation. Malignant variants of PVCs may induce ventricular fibrillation even in a normal heart. PMID:27521085

  4. Pattern Organization of Premature Ventricular Heartbeats

    NASA Astrophysics Data System (ADS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Ivanov, Plamen; Stanley, H. Eugene; Stanley, Gene; Goldberger, Ary L.

    2000-03-01

    Increased number of premature (abnormal) ventricular beats in a record of heartbeat intervals are known to be associated with an advanced stage of pathology (e.g. congestive heart failure). These abnormal beats usually occur in repeated bursts for relatively short periods of time. Here we ask the question if particular abnormal patterns appear throughout records of heartbeat intervals. We study the temporal organization of specific patterns of ventricular beats in long 24 hour records and their relation to different stages of disease. We analyze the statistical properties of such patterns and combination of patterns by means of crosscorrelation matrices.

  5. Arrhythmias in two patients with left ventricular bypass transplants.

    PubMed Central

    Kennelly, B M; Corte, P; Losman, J; Barnard, C N

    1976-01-01

    Two patients who underwent left ventricular bypass transplants are described. Both patients sustained postoperative rhythm disturbances of their own hearts during sinus rhythm of the donor hearts. Illustrative examples of atrial flutter, ventricular flutter, ventricular fibrillation, blocked atrial extrasystoles, and double ventricular parasystole in the recipient hearts are presented. The patients tolerated all these arrhythmias well during uninterrupted sinus rhythm in the donor heart. The problems in interpretation of arrhythmias in the presence of two hearts are discussed. Images PMID:788729

  6. A study on premature ventricular contractions caused by ultrasound exposure with microbubbles using cultured ventricular muscle cells

    NASA Astrophysics Data System (ADS)

    Kudo, N.; Yokoyama, G.; Ikebuchi, M.; Okada, K.; Kawahara, K.; Yamamoto, K.

    2004-01-01

    It has been shown that diagnostic ultrasound examination using a contrast agent can cause premature ventricular contractions (PVCs). In this study, we investigated a usefulness of a new technique using cultured cardiac myocytes to study mechanisms of PVC production. Cardiac myocytes were isolated from neonatal rats and cultured on a cover glass. The cover glass was attached to an observation chamber in which it was possible to observe changes in myocytes during ultrasound exposure. In the experiments, cardiac myocytes were exposed to pulsed ultrasound in the presence and absence of microbubbles. The pressure amplitudes (peak-negative pressures) were set at 5 steps, -0.28, -0.55, -0.73, -0.92 and -1.1 MPa, and threshold pressure to produce a PVC was recorded. The results showed that the presence of microbubbles attached to a cell reduces threshold pressure for producing PVCs, and it was concluded that our method is useful for studying the mechanisms of PVC production.

  7. A Case Report of Renal Sympathetic Denervation for the Treatment of Polymorphic Ventricular Premature Complexes

    PubMed Central

    Kiuchi, Márcio Galindo; Vitorio, Frederico Puppim; da Silva, Gustavo Ramalho; Paz, Luis Marcelo Rodrigues; Souto, Gladyston Luiz Lima

    2015-01-01

    Abstract Premature ventricular complexes are very common, appearing most frequently in patients with hypertension, obesity, sleep apnea, and structural heart disease. Sympathetic hyperactivity plays a critical role in the development, maintenance, and aggravation of ventricular arrhythmias. Recently, Armaganijan et al reported the relevance of sympathetic activation in patients with ventricular arrhythmias and suggested a potential role for catheter-based renal sympathetic denervation in reducing the arrhythmic burden. In this report, we describe a 32-year-old hypertensive male patient presenting with a high incidence of polymorphic premature ventricular complexes on a 24 hour Holter monitor. Beginning 1 year prior, the patient experienced episodes of presyncope, syncope, and tachycardia palpitations. The patient was taking losartan 100 mg/day, which kept his blood pressure (BP) under control, and sotalol 160 mg twice daily. Bisoprolol 10 mg/day was used previously but was not successful for controlling the episodes. The 24 hour Holter performed after the onset of sotalol 160 mg twice daily showed a heart rate ranging between 48 (minimum)–78 (average)–119 (maximum) bpm; 14,286 polymorphic premature ventricular complexes; 3 episodes of nonsustained ventricular tachycardia, the largest composed of 4 beats at a rate of 197 bpm; and 14 isolated atrial ectopic beats. Cardiac magnetic resonance imaging with gadolinium perfusion performed at rest and under pharmacological stress with dipyridamole showed increased left atrial internal volume, preserved systolic global biventricular function, and an absence of infarcted or ischemic areas. The patient underwent bilateral renal sympathetic denervation. The only drug used postprocedure was losartan 25 mg/day. Three months after the patient underwent renal sympathetic denervation, the mean BP value dropped to 132/86 mmHg, the mean systolic/diastolic 24 hour ambulatory BP measurement was reduced to 128/83

  8. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545 Ventricular bypass (assist) device. (a) Identification. A ventricular bypass (assist) device is a device that assists... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ventricular bypass (assist) device....

  9. Left ventricular pseudoaneurysm perceived as a left lung mass

    PubMed Central

    Yaliniz, Hafize; Gocen, Ugur; Atalay, Atakan; Salih, Orhan Kemal

    2016-01-01

    Left ventricular pseudoaneurysm is a rare complication of aneurysmectomy. We present a case of a surgically treated left ventricular pseudoaneurysm, which was diagnosed three years after coronary artery bypass grafting and left ventricular aneurysmectomy. The presenting symptoms, diagnostic evaluation, and surgical repair are described. PMID:27516793

  10. Effect of temperature on rate of left ventricular pressure fall in humans.

    PubMed Central

    Luke, R A; Gillbe, C E; Bonser, R S; Paneth, M; Somerset, D; Thomas, J; Gibson, D G

    1989-01-01

    The time constant (T) of left ventricular pressure fall is widely used as an index of ventricular "relaxation". It is not known whether its rate limiting step is deactivation, an enzymic energy consuming reaction whose rate is therefore sensitive to temperature, or elastic recoil. To distinguish between these possibilities, the time constant was measured by simple logarithmic (Tlog) and exponential (Texp) methods in 12 patients during cooling before coronary artery grafting. Ventricular loading conditions were altered by transfusion from bypass to maintain arterial and left atrial pressures constant in individual patients, though heart rate fell from 86 (8.4) to 68 (10) beats/min. Tlog increased from 49 (10) ms mean (SD), at 37 degrees C to 86 (15) ms at 31 degrees C, and Texp from 63(14) at 37 degrees C to 112 (23) ms at 31 degrees C with intermediate values at 34 degrees C. Texp proved sensitive to "noise" at low temperatures, but the overall change in Tlog with temperature was 9% per degree C--considerably less than that observed experimentally for the rate of tension decline of isolated myocardium, and possibly itself an overestimate because of the concomitant fall in heart rate. The relatively small effect of temperature on Tlog in humans, associated with a considerable load sensitivity appearing under hypothermic conditions, does not favour simple dependence on deactivation as the rate limiting step of left ventricular pressure fall, but suggests that its determinants may be complex. PMID:2736194

  11. Acute inferior myocardial infarction with right ventricular infarction is more prone to develop cardiogenic shock.

    PubMed

    Bari, M A; Roy, A K; Islam, M Z; Aditya, G; Bhuiyan, A S

    2015-01-01

    Cardiogenic shock is rare in isolated acute inferior myocardial infarction but there is relationship of cardiogenic shock with inferior myocardial infarction if associated with right ventricular infarction. A prospective study was carried out to see the association of cardiogenic shock with inferior myocardial infarction if associated with right ventricular infarction. This study was conducted from January 2011 to November 2011. A total of 100 cases were selected as study population which was taken from the Department of Cardiology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh. Among them 50 were in Group A and 50 were in Group B. Group A was the patients of acute myocardial infarction with right ventricular infarction. Group B was the patients of acute myocardial infarction without right ventricular infarction. It revealed that 9(18%) in Group A and 3(6%) in Group B developed cardiogenic shock which is statistically significant (p<0.05). The study concluded that AMI (Inf) with RVI is significantly associated with cardiogenic shock.

  12. A murine experimental model for the mechanical behaviour of viable right-ventricular myocardium

    PubMed Central

    Valdez-Jasso, Daniela; Simon, Marc A; Champion, Hunter C; Sacks, Michael S

    2012-01-01

    Although right-ventricular function is an important determinant of cardio-pulmonary performance in health and disease, right ventricular myocardium mechanical behaviour has received relatively little attention. We present a novel experimental method for quantifying the mechanical behaviour of transmurally intact, viable right-ventricular myocardium. Seven murine right ventricular free wall (RVFW) specimens were isolated and biaxial mechanical behaviour measured, along with quantification of the local transmural myofibre and collagen fibre architecture. We developed a complementary strain energy function based method to capture the average biomechanical response. Overall, murine RVFW revealed distinct mechanical anisotropy. The preferential alignment of the myofibres and collagen fibres to the apex-to-outflow-tract direction was consistent with this also being the mechanically stiffer axis. We also observed that the myofibre and collagen fibre orientations were remarkably uniform throughout the entire RVFW thickness. Thus, our findings indicate a close correspondence between the tissue microstructure and biomechanical behaviour of the RVFW myocardium, and are a first step towards elucidating the structure–function of non-contracted murine RVFW myocardium in health and disease. PMID:22848044

  13. Outpatient management of intra-corporeal left ventricular assist device system in children: a multi-center experience.

    PubMed

    Schweiger, M; Vanderpluym, C; Jeewa, A; Canter, C E; Jansz, P; Parrino, P E; Miera, O; Schmitto, J; Mehegan, M; Adachi, I; Hübler, M; Zimpfer, D

    2015-02-01

    Little is known about the outcomes of children supported on intracorporeal left ventricular assist device (HVAD), and the feasibility of outpatient management. All centers with pediatric patients discharged from the hospital on the device were identified using company database. A total of 14 centers were contacted, with 9 centers, contributing data retrospectively. From 2011 to 2013, 12 pediatric patients (7 females), mean aged 11.9 ± 2.3 years (range 8-15), mean weight 43 ± 19 kg (range 18-81), mean body surface area 1.3 ± 0.3 m(2) (range 0.76-1.96) were identified. Diagnosis included: dilated cardiomyopathy (CMP) (n = 5), noncompaction CMP (n = 4), toxic CMP (n = 2) and viral CMP (n = 1). Indications for support were permanent support (n = 1), bridge to recovery (n = 1) and bridge to transplantation (n = 10). Prior to HVAD implantation, all patients received intravenous inotropes and two patients were on temporary mechanical support. Overall mortality was 0%. Mean duration of inpatient and outpatient support were 56 (range: 19-95 days) and 290 days (range: 42-790), respectively. Mean readmission rate was 0.02 per patient month (2.1 per patient). No adverse events involving emergency department occurred. Eight children resumed local schooling. Home discharge of children supported on HVAD is feasible and safe. School integration can be achieved. There is wide center variability to discharge practice for children.

  14. Positive inotropic effect of porcine left ventricular extract on canine ventricular muscle.

    PubMed Central

    Navaratnam, S.; Chau, T.; Agbanyo, M.; Bose, D.; Khatter, J. C.

    1990-01-01

    1. We previously isolated an extract from porcine left ventricle that possessed digitalis-like properties such as inhibition of cardiac and kidney Na+, K(+)-ATPase, displacement of [3H]-ouabain from its binding sites and cross reactivity with digoxin antibodies. The extract also had a positive inotropic effect on the guinea-pig heart. 2. In the present study the positive inotropic response of the extract was characterized in canine right ventricular trabeculae. Maximum inotropic response (501 +/- 20%) was produced by 300 microliters and the half maximal increase occurred with 125 microliters of the extract. 3. Ouabagenin produced aftercontractions in rapidly paced trabeculae. Equipotent and even greater amounts of the extract did not produce aftercontractions. 4. The extract increased the amplitude of the delayed component (P2) of biphasic contractions produced by replacing about 92-96% of the external Ca with Sr. A smaller increase in the size of the early component (P1) was also seen. 5. The extract decreased post-rest potentiation after rest for 30s and 2 min. After 8 min of rest, post-rest potentiation was converted to post-rest depression. 6. The extract (20 microliters) produced a decrease in the amplitude of the post-rest rapid cooling contracture (RCC) at all rest intervals. The steady state RCC, although greater than that in the control muscle, was increased to a lesser extent than the size of the steady state electrically driven contractions. 7. It is suggested that the extract from porcine left ventricle produces a positive inotropic response by increasing the trans-sarcolemmal influx of Ca.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2257439

  15. Epicardial and endocardial mapping determine most successful site of ablation for ventricular tachyarrhythmias originating from left ventricular summit.

    PubMed

    Iijima, Kenichi; Chinushi, Masaomi; Furushima, Hiroshi; Aizawa, Yoshifusa

    2012-06-01

    A 34-year-old woman presented with idiopathic premature ventricular complex (PVC) and ventricular tachycardia (VT) originating from the area called the left ventricular summit. Radiofrequency (RF) application both through the coronary sinus and to the epicardial surface transiently suppressed the VT/PVC. Radiofrequency with sufficient energy was only applicable from the endocardial site, and the VT/PVC was successfully eliminated.

  16. Radionuclide analysis of right and left ventricular response to exercise in patients with atrial and ventricular septal defects

    SciTech Connect

    Peter, C.A.; Bowyer, K.; Jones, R.H.

    1983-03-01

    In patients with ventricular or atrial septal defect, the ventricle which is chronically volume overloaded might not appropriately respond to increased demand for an augmentation in output and thereby might limit total cardiac function. In this study we simultaneously measured right and left ventricular response to exercise in 10 normal individuals, 10 patients with ventricular septal defect (VSD), and 10 patients with atrial septal defect (ASD). The normal subjects increased both right and left ventricular ejection fraction, end-diastolic volume, and stroke volume to achieve a higher cardiac output during exercise. Patients with VSD failed to increase right ventricular ejection fraction, but increased right ventricular end-diastolic volume and stroke volume. Left ventricular end-diastolic volume did not increase in these patients but ejection fraction, stroke volume, and forward left ventricular output achieved during exercise were comparable to the response observed in healthy subjects. In the patients with ASD, no rest-to-exercise change occurred in either right ventricular ejection fraction, end-diastolic volume, or stroke volume. In addition, left ventricular end-diastolic volume failed to increase, and despite an increase in ejection fraction, left ventricular stroke volume remained unchanged from rest to exercise. Therefore, cardiac output was augmented only by the heart rate increase in these patients. Right ventricular function appeared to be the major determinant of total cardiac output during exercise in patients with cardiac septal defects and left-to-right shunt.

  17. Mechanisms of ventricular arrhythmias: a perspective.

    PubMed

    Kléber, A G

    1991-01-01

    The most important ventricular arrhythmias, the ventricular tachycardias (VTs) and ventricular fibrillations (VFs), are thought to underlie the majority of cases of sudden cardiac death. In ischemic heart disease, they can be divided into several pathophysiological entities: (a) arrhythmias occurring during the acute reversible phase of ischemia, (b) arrhythmias taking place during reperfusion of acutely ischemic myocardium, (c) arrhythmias occurring 24-72 h after acute infarction, and (d) arrhythmias associated with chronic infarction. In all three settings, the mechanisms sustaining ventricular arrhythmias need to be distinguished from initiating mechanisms. With the exception of the 24-72-h stage, these arrhythmias are sustained by circus movement with reentry: the electrophysiological determinants of circus movements at a cellular level and, consequently, the appearance of the circulating wave fronts, differ according to the ischemic phase. In acute ischemia, multiple circulating waves, with somewhat large diameters, change their vortexes from beat to beat. In chronic infarction, the location of the stable circuits with elongated central zones of block are closely related to myocardial fiber architecture and probably to scar tissue. These differences indicate that (a) in acute ischemia, the conduction disturbances are mainly determined by the development of inexcitability at the level of cardiac membranes; and (b) in chronic infarction, the site of conduction block and the pivoting points of the wave fronts are determined by impairment of electrical cell-to-cell coupling. In contrast to the mechanisms sustaining VT and VF, the initiating mechanisms are less well defined.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1723111

  18. Catheter ablation of parahisian premature ventricular complex.

    PubMed

    Kim, Jun; Kim, Jeong Su; Park, Yong Hyun; Kim, June Hong; Chun, Kook Jin

    2011-12-01

    Catheter ablation is performed in selected patients with a symptomatic premature ventricular complex (PVC) or PVC-induced cardiomyopathy. Ablation of PVC from the His region has a high risk of inducing a complete atrioventricular block. Here we report successful catheter ablation of a parahisian PVC in a 63-year-old man.

  19. Ventricular myoarchitecture in tetralogy of Fallot.

    PubMed Central

    Sanchez-Quintana, D.; Anderson, R. H.; Ho, S. Y.

    1996-01-01

    BACKGROUND: Little attention has been paid to the architecture of the muscle fibres of the ventricular walls in congenitally malformed hearts. In this study the gross pattern of myocardial fibres in normal hearts was compared with that in cases of tetralogy of Fallot. METHODS AND RESULTS: After morphological examination nine specimens with tetralogy were dissected to study the ventricular myoarchitecture. Changes were found in the shape of the malformed ventricles. The ventricular walls were arranged in layers in all hearts. Superficial and deep layers were present in both ventricles, with the superficial layer showing a more oblique orientation in the specimens with tetralogy than in normal hearts. Modifications of muscle fibre that were related to the type of malformation were seen in the deep layer. A middle layer was present in the left ventricles of normal hearts and specimens with tetralogy: this showed a horizontal orientation in both groups. In contrast, a middle layer was found in the right ventricle only in specimens showing tetralogy. CONCLUSIONS: The malformed hearts showed modifications in ventricular shape, in the arrangement of muscle in the right ventricle, and in the overall myoarchitecture. These changes could well be the consequence of the same agent (or agents) that caused the structural defect. Images PMID:8868990

  20. [Current management of patients with ventricular tachycardia].

    PubMed

    Puljević, D; Buljević, B; Milicić, D

    2001-01-01

    Ventricular arrhythmia has for decades been considered as a premonitory sign and risk marker of sudden death. Novel theories about arrhythmogenesis and conditions for the occurrence of sudden death, as well as evidence about proarrhythmic effect of antiarrhythmic drugs, have changed the views on the treatment of ventricular arrhythmia. Ventricular tachycardia (VT) is most often associated with structural heart disease: ischemic heart disease and previous myocardial infarction, cardiomyopathy (dilated and hypertrophic), arrhythmogenic right ventricular dysplasia, valvular heart disease (mitral valve prolapse), heart failure, condition after surgical correction of a congenital heart disease. Sometimes VT occurs without structural heart disease (congenital LQTS, Brugada syndrome, idiopathic VT). Today's standpoint is to treat only symptomatic and/or prognostically significant arrhythmias. Prognostic significance of VT mostly depends on the type and degree of structural heart disease and on global cardiac function. In patients with asymptomatic non-sustained VT and low risk for sudden death no treatment is needed or antiarrhythmics are administered. Conversely, in high risk patients implantation of automatic cardioverter-defibrillator is indicated. In the treatment of acute attack of VT the following can be used: electroconversion, cardiac pacing (overdrive), lidocaine, amiodarone, beta-blockers, and occasionally magnesium or verapamil. In the prevention of recurrent arrhythmia and sudden death we can use: amiodarone, sotalol, mexiletin, phenytoin, beta-blockers, radiofrequency ablation, implantable cardioverter-defibrillator, and in specific patients verapamil, pacemaker or left ganglion stellatum denervation.

  1. Diagnosis and management of ventricular dysphonia.

    PubMed

    Von Hake, C P; Ganzman, I P; Mauer, T P

    1989-02-01

    Ventricular phonation may develop on a functional level, or it may occur as an alternative voice for the patient who has an organic disease of the true vocal folds. Three cases that represent iatrogenic, traumatic, and neurologic forms of the disorder are reported. Diagnosis, treatment, and guidelines for follow-up speech therapy are discussed.

  2. Comparison of effectiveness of right ventricular septal pacing versus right ventricular apical pacing.

    PubMed

    Cano, Oscar; Osca, Joaquín; Sancho-Tello, María-José; Sánchez, Juan M; Ortiz, Víctor; Castro, José E; Salvador, Antonio; Olagüe, José

    2010-05-15

    Chronic right ventricular apical pacing (RVAP) has been associated with negative hemodynamic and clinical effects. The aim of the present study was to compare RVAP with right ventricular septal pacing (RVSP) in terms of echocardiographic features and clinical outcomes. A total of 93 patients without structural heart disease and with an indication for a permanent pacemaker were randomly assigned to receive a screw-in lead either in the RV apex (n = 46) or in the RV mid-septum (n = 47). The patients were divided into 3 subgroups according to the percentage of ventricular pacing: control group (n = 21, percentage of ventricular pacing < or =10%), RVAP group (n = 28), or RVSP group (n = 32; both latter groups had a percentage of ventricular pacing >10%). The RVAP group had more intraventricular dyssynchrony and a trend toward a worse left ventricular ejection fraction compared to the RVSP and control groups at 12 months of follow-up (maximal delay to peak systolic velocity between any of the 6 left ventricular basal segments was 57.8 +/- 38.2, 35.5 +/- 20.6, and 36.5 +/- 17.8 ms for RVAP, RVSP, and control group, respectively; p = 0.006; mean left ventricular ejection fraction 62.9 +/- 7.9%, 66.5 +/- 7.2%, and 66.6 +/- 7.2%, respectively, p = 0.14). Up to 48.1% of the RVAP patients showed significant intraventricular dyssynchrony compared to 19.4% of the RVSP patients and 23.8% of the controls (p = 0.04). However, no overt clinical benefits from RVSP were found. In conclusion, RVAP was associated with increased dyssynchrony compared to the RVSP and control patients. RVSP could represent an alternative pacing site in selected patients to reduce the harmful effects of traditional RVAP. PMID:20451689

  3. Catheter ablation of ventricular tachycardia related to a septo-apical left ventricular aneurysm

    PubMed Central

    Rosu, Radu; Cismaru, Gabriel; Muresan, Lucian; Puiu, Mihai; Andronache, Marius; Gusetu, Gabriel; Pop, Dana; Mircea, Petru-Adrian; Zdrenghea, Dumitru

    2015-01-01

    A 60-year-old male patient with previous myocardial infarction (30 years ago) presented to our cardiology department for sustained monomorphic ventricular tachycardia. The patient presented multiple episodes of tachycardia treated by his internal cardiac defibrillator. Radiofrequency ablation was proposed as curative treatment. The mechanism of the ventricular tachycardia was demonstrated by electrophysiological study using three-dimensional mapping system: Carto 3 (Biosense Webster). Ventricular tachycardia was induced either mechanically or by programmed ventricular stimulation. The tachycardia cycle length was 380 msec. The voltage map confirmed the presence of the septo-apical aneurysm with a local voltage < 0.5 mV. Activation mapping revealed a figure-in-8 circuit of VT with the entrance point inside the dense scar and the exit point at the border zone (between the aneurysm and the healthy tissue of the left ventricular septo-apical region). Radiofrequency energy was delivered at the isthmus of the tachycardia rendering it uniducible by programmed ventricular stimulation. PMID:26770613

  4. Fontan-Like Hemodynamics Complicated With Ventricular Fibrillation During Left Ventricular Assist Device Support.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Nitta, Daisuke; Kinoshita, Osamu; Nawata, Kan; Ono, Minoru

    2016-07-27

    We experienced a patient who had received an implantable continuous-flow left ventricular assist device (LVAD) (HeartMate II, Thoratec Corp, Pleasanton, CA, USA) and was admitted to our hospital because of repeated ventricular tachyarrhythmias refractory to electrical defibrillation as well as intensive pharmacological therapy. We decided to discontinue defibrillating, but under ventricular fibrillation his hemodynamics were maintained without end-organ dysfunction during LVAD support (mean right atrial pressure 18 mmHg; pulmonary vascular resistance 1.6 WU; pulmonary capillary wedge pressure 11 mmHg; cardiac index 2.04 L/minute/m(2)) due to optimization of the rotation speed (from 8800 to 9200 rpm). Such "Fontan-like circulation" could be accomplished by adequate volume control, lowering pulmonary vascular resistance, and potent LV blood removal by optimal rotation speed of the LVAD, although the precise conditions to maintain the Fontan-like circulation during LVAD therapy remained uncertain. Considering the severe donor heart shortage and high degree of difficulty of the catheter ablation procedure to manage ventricular tachyarrhythmias, constructing a Fontan-like circulation in the presence of ventricular tachyarrhythmias may be one unique strategy. Longterm prognosis in patients with sustained ventricular tachyarrhythmias during LVAD support would be a future concern. PMID:27385606

  5. Left ventricular function in chronic aortic regurgitation

    SciTech Connect

    Iskandrian, A.S.; Hakki, A.H.; Manno, B.; Amenta, A.; Kane, S.A.

    1983-06-01

    Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability (p) . 0.02) and during exercise (p . 0.0002), higher cardiac index at exercise (p . 0.0008) and lower exercise end-systolic volume (p . 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p . 0.001) and cardiac index at rest (p . 0.03) and exercise (p . 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.

  6. The multiple electrocardiographic manifestations of ventricular repolarization memory.

    PubMed

    Chiale, Pablo A; Etcheverry, Daniel; Pastori, Julio D; Fernandez, Pablo A; Garro, Hugo A; González, Mario D; Elizari, Marcelo V

    2014-08-01

    T wave "memory" is a peculiar variety of cardiac remodeling caused by a transient change in the course of ventricular depolarization (due to ventricular pacing, rate-dependent intraventricular block, ventricular preexcitation or tachyarrhythmias with wide QRS complexes). It is usually manifested by inverted T waves that appears when normal ventricular activation is restored. This phenomenon is cumulative and occurs earlier if the ventricular myocardium has previously been exposed to the same conditioning stimuli. In this article the different conditions giving rise to "classical" T wave memory development are reviewed and also "another" type of T wave memory is described. It is also shown that cardiac memory may induce not only negative (pseudo-primary) T waves but also a reversal of primary and pseudoprimary T waves leading to "normalization" of ventricular repolarization. The knowledge of these dissimilar consequences of T wave memory is essential to assess the characteristics of ventricular repolarization.

  7. Role of signal-averaged electrocardiography and ventricular late potentials in patients with chronic obstructive pulmonary disease.

    PubMed

    Buzea, C A; Dan, G A; Dan, Anca Rodica; Delcea, Caterina; Balea, M I; Gologanu, Daniela Stefana; Dobranici, Mihaela; Popescu, Raluca Alexandra

    2015-01-01

    Patients with chronic obstructive pulmonary disease (COPD) have an increased risk for cardiac arrhythmias. Ventricular late potentials (VLP) on signal-averaged electrocardiography (SAECG) are associated with an increased risk for malignant ventricular arrhythmias. Our aim is to investigate the modifications of SAECG parameters and the presence of VLP as possible indicators of proarrhythmic substrate in patients with COPD. We prospectively enrolled 41 consecutive patients in the COPD group and 63 patients without any history of pulmonary disease, matched for age and hypertension history, in the control group. Pulmonary function tests, arterial blood gases, echocardiography, 24-hour Holter monitoring and SAECG were performed. We measured total filtered QRS duration (QRSf), duration of high frequency, low-amplitude signals < 40 V (HFLA40), and root mean square voltage in the last 40 ms (RMS40). VLP were considered if at least two of these parameters were abnormal. Results. We did not register any significant differences in QRSf, HFLA40 or RMS40 between the two groups. In the COPD group there was a non-significant higher percentage of patients with VLP in comparison with the control group. In the COPD patients we registered a significantly higher number of isolated premature ventricular beats and of combined complex ventricular arrhythmias, consisting of polymorphic PVC, couplets, triplets or nonsustained ventricular tachycardias. None of these arrhythmic parameters correlated with SAECG variables or with the presence of VLP. Conclusion. In COPD patients parameters measured on signal-averaged electrocardiography and ventricular late potentials analysis have little value in risk stratification for ventricular arrhythmias.

  8. Right ventricular filling in dilated cardiomyopathy.

    PubMed Central

    Fujimoto, S.; Parker, K. H.; Gibson, D. G.

    1995-01-01

    PURPOSE--To assess right ventricular filling in dilated cardiomyopathy. PATIENTS--32 patients with dilated cardiomyopathy and 24 healthy controls. METHODS--Stroke distances were measured by pulsed Doppler echocardiography at left ventricular outflow and left and right ventricular inflow. The inflow tract dimensions of both ventricles and the outflow tract dimension of the left ventricle were measured from two dimensional images. Right and left sided atrioventricular (AV) ring excursions were measured by M mode echocardiography at the tricuspid and mitral rings. Stroke volume was derived as stroke distance multiplied by left ventricular outflow tract area. Total stroke distances were calculated as the sum of AV valve Doppler stroke distances and ring excursion. The effective orifice areas of the two AV valves were thus defined as stroke volumes divided by total stroke distance. RESULTS--Total tricuspid stroke distance was normally less than mitral (6.0 (1.7) v 7.6 (1.7) cm, P < 0.05), implying that effective orifice area of the tricuspid valve was consistently greater (6.6 (1.6) v 4.5 (0.8) cm2, P < 0.01). Total tricuspid ring excursion was normally more than mitral (2.30 (0.30) v 1.62 (0.22) cm, P < 0.01). Total tricuspid stroke distance in dilated cardiomyopathy was also less than mitral (7.8 (2.4) v 9.7 (2.8) cm, P < 0.05). Tricuspid stroke distance was significantly increased in patients with dilated cardiomyopathy compared with that in healthy controls (P < 0.05 v controls), though stroke volume was much smaller (26 (10) v 63 (11) ml, P < 0.01) so that tricuspid effective orifice area was reduced to less than half normal (2.7 (1.2) cm2, P < 0.01). Total tricuspid ring long axis excursion was more than mitral (1.37 (0.6) v 0.74 (0.21) cm, P < 0.01). Right ventricular end diastolic inflow dimension was increased compared with that in healthy controls (3.9 (0.7) v 2.8 (0.5) cm, P < 0.01), correlating inversely with tricuspid effective orifice area (r = -0.71, P

  9. Increased dispersion of ventricular repolarization and ventricular tachyarrhythmias in the globally ischaemic rabbit heart.

    PubMed

    Kurz, R W; Xiao-Lin, R; Franz, M R

    1993-11-01

    Contemporary concepts of ischaemic ventricular tachyarrhythmias (VTA) are based on increased electrophysiological heterogeneity of the myocardium. We developed a multi-site monophasic action potential recording system for an isolated rabbit heart to study the effects of global ischaemia on the electrophysiological properties at different ventricular sites simultaneously. The hearts were paced from the right ventricle (RV), and conduction time (CT), action potential duration (APD) and total repolarization time (TRT = [CT + APD]) were measured during normal perfusion and ischaemia. The dispersion of these parameters was calculated as the maximal difference between simultaneous recordings. Inducibility of VTA by programmed extrastimulation (ES) was investigated under normal and ischaemic conditions. During global ischaemia, CT increased progressively, showing a faster and greater increase at the left ventricle (LV) than at the RV. After 10 min the prolongation of CT reached a plateau at the LV while it continued to rise in the RV. The dispersion of CT increased from 14.5 +/- 2.7 ms during normal perfusion to a maximum of 79.8 +/- 17.2 ms after 14 min of ischaemia (P < 0.0001). APD was uniform at the three sites (190.9 +/- 10.2, 185.0 +/- 8.6 and 179.3 +/- 9.8 ms, ns) during normal perfusion but changed non-uniformly during ischaemia. There was a transient lengthening of APD until 1 and 3 min of ischaemia at the LV sites followed by a rapid shortening of APD. At the RV site, APD continued to increase until 5 min of ischaemia and then shortened gradually. Consequently, dispersion of APD showed a rapid initial rise from 17.7 +/- 2.7 ms to 77.8 +/- 10.2 ms (P < 0.0001) followed by a slower final increase. TRT was uniform during normal perfusion (210.4 +/- 10.3, 213.1 +/- 7.8, 212.1 +/- 10.3 ms, ns) but became non-uniform during global ischaemia. The dispersion of TRT increased from 15.4 +/- 4.2 ms to 92.6 +/- 23.2 ms (P < 0.0001) during 14 min of global ischaemia. Both CT

  10. Transmitral exclusion of a giant congenital left ventricular aneurysm associated with mitral insufficiency in adult.

    PubMed

    El Malki, Hicham; El Kandoussi, Tahar; Rhissassi, Jaafar; Laaroussi, Mohamed

    2015-12-01

    Congenital left ventricular aneurysm is rare, poorly understood and potentially lethal. It usually occurs in isolation. Its combination with mitral insufficiency is an uncommon entity. Because the literature on this kind of aneurysms consists of case reports and small series described especially in children, we report here an interesting and unique case of an adult aged 35 years bearing simultaneously a congenital left ventricular aneurysm and mitral insufficiency. Without medical past history, he consults for palpitations and dyspnoea. Once diagnosis was made by chest X-ray, echocardiography and computed tomography, an open heart surgery was necessary to prevent complications. Through a transmitral approach, aneurysmal exclusion was performed by closing the aneurysmal collar with a Dacron patch and mitral replacement was accomplished. At 12 months, follow-up was favourable without residual communication between aneurysm and ventricle or paraprosthetic leak. PMID:26399261

  11. Prenatal diagnosis of left ventricular diverticulum and coarctation of the aorta.

    PubMed

    Hunter, L E; Pushparajah, K; Miller, O; Anderson, D; Simpson, J M

    2016-02-01

    Congenital left ventricular diverticulum (LVD) is a rare abnormality of the myocardium which has been detected previously in the fetus. Lesions have been reported from as early as 12 weeks' gestation but are more commonly detected in the mid-second trimester. Fetal presentation of LVD ranges from an abnormal four-chamber view of the heart, arrhythmia or isolated pericardial effusion to fetal hydrops with associated heart failure. Here, we describe the prenatal diagnosis of an infant with LVD originating from the left ventricular outflow tract associated with coarctation of the aorta. The diagnosis was confirmed postnatally by two-dimensional echocardiography and cardiac magnetic resonance imaging. We hypothesize that the lesion compromised antegrade flow into the transverse aortic arch, which may have contributed to underdevelopment of the aortic arch and subsequently the development of coarctation of the aorta. This is a unique case of LVD and coarctation of the aorta. PMID:26376444

  12. Electrocardiographic and morphometric features in patients with ventricular tachycardia of right ventricular origin

    PubMed Central

    Kazmierczak, J; De Sutter, J; Tavernier, R; Cuvelier, C; Dimmer, C; Jordaens, L

    1998-01-01

    Objective—To study differences between repetitive monomorphic ventricular tachycardia (RMVT) of right ventricular origin, and ventricular tachycardia in arrhythmogenic right ventricular dysplasia (ARVD).
Patients—Consecutive groups with RMVT (n = 15) or ARVD (n = 12), comparable for age and function.
Methods—Analysis of baseline, tachycardia, and signal averaged ECGs, clinical data, and right endomyocardial biopsies. Pathological findings were related to regional depolarisation (QRS width) and repolarisation (QT interval, QT dispersion).
Results—There was no difference in age, ejection fraction, QRS width in leads I, V1, and V6, and QT indices. During ventricular tachycardia, more patients with ARVD had a QS wave in V1 (p < 0.05). There were significant differences for unfiltered QRS, filtered QRS, low amplitude signal duration, and the root mean square voltage content. In the absence of bundle branch block, differences became non-significant for unfiltered and filtered QRS duration. Mean (SD) percentage of biopsy surface differed between RMVT and ARVD: normal myocytes (74(3.4)% v 64.5(9.3)%; p < 0.05); fibrosis (3(1.7)% v 8.9(5.2)%; p < 0.05). When all patients were included, there were significant correlations between fibrosis and age (r = 0.6761), and fibrosis and QRS width (r = 0.5524 for lead I; r = 0.5254 for lead V1; and r = 0.6017 for lead V6).
Conclusions—The ECG during tachycardia and signal averaging are helpful in discriminating between ARVD and RMVT patients. There are differences in the proportions of normal myocytes and fibrosis. The QRS duration is correlated with the amount of fibrous tissue in patients with ventricular tachycardia of right ventricular origin.

 Keywords: arrhythmogenic right ventricular dysplasia;  electrocardiography;  endomyocardial biopsy;  ventricular arrhythmias PMID:9616349

  13. Left Ventricular Dilatation Increases the Risk of Ventricular Arrhythmias in Patients With Reduced Systolic Function

    PubMed Central

    Aleong, Ryan G; Mulvahill, Matthew J; Halder, Indrani; Carlson, Nichole E; Singh, Madhurmeet; Bloom, Heather L; Dudley, Samuel C; Ellinor, Patrick T; Shalaby, Alaa; Weiss, Raul; Gutmann, Rebecca; Sauer, William H; Narayanan, Kumar; Chugh, Sumeet S; Saba, Samir; London, Barry

    2015-01-01

    Background Reduced left ventricular (LV) ejection fraction increases the risk of ventricular arrhythmias; however, LV ejection fraction has a low sensitivity to predict ventricular arrhythmias. LV dilatation and mass may be useful to further risk-stratify for ventricular arrhythmias. Methods and Results Patients from the Genetic Risk of Assessment of Defibrillator Events (GRADE) study (N =930), a study of heart failure subjects with defibrillators, were assessed for appropriate implantable cardioverter-defibrillator shock and death, heart transplant, or ventricular assist device placement by LV diameter and mass. LV mass was divided into normal, mild, moderate, and severe classifications. Severe LV end-diastolic diameter had worse shock-free survival than normal and mild LV end-diastolic diameter (P =0.0002 and 0.0063, respectively; 2-year shock free, severe 74%, moderate 80%, mild 91%, normal 88%; 4-year shock free, severe 62%, moderate 69%, mild 72%, normal 81%) and freedom from death, transplant, or ventricular assist device compared with normal and moderate LV end-diastolic diameter (P<0.0001 and 0.0441, respectively; 2-year survival: severe 78%, moderate 85%, mild 82%, normal 89%; 4-year survival: severe 55%, moderate 64%, mild 63%, normal 74%). Severe LV mass had worse shock-free survival than normal and mild LV mass (P =0.0370 and 0.0280, respectively; 2-year shock free: severe 80%, moderate 81%, mild 91%, normal 87%; 4-year shock free: severe 68%, moderate 73%, mild 76%, normal 76%) but no association with death, transplant, or ventricular assist device (P =0.1319). In a multivariable Cox proportional hazards analysis adjusted for LV ejection fraction, LV end-diastolic diameter was associated with appropriate implantable cardioverter-defibrillator shocks (hazard ratio 1.22, P =0.020). LV end-diastolic diameter was associated with time to death, transplant, or ventricular assist device (hazard ratio 1.29, P =0.0009). Conclusions LV dilatation may complement

  14. Morphometric analysis of cerebral ventricular system from MR images

    NASA Astrophysics Data System (ADS)

    Aziz, Aamer; Hu, QingMao; Nowinski, Wieslaw L.

    2004-04-01

    Cerebrospinal fluid filled ventricular system is an essential part of brain. The volume, shape and size of this ventricular system remain more or less constant and various pathologies directly or indirectly affect them. Morphometric analysis of cerebral ventricular system is important for evaluating changes due to growth, aging, intrinsic and extrinsic pathologies. Previous quantification efforts using ex vivo techniques suffered considerable error due to deformation of slices during sectioning, and numerous other factors. In vivo studies using air or contrast media also introduce volumetric changes in the ventricles thus giving erroneous quantitative information. Imaging of ventricular anatomy avoids these problems and allows repetitive studies following progression of ventricular system changes due to disease or natural processes. We have developed a methodology for automated extraction of ventricular system from MR neuroimages. Once extracted, landmarks are located on the surface of ventricular system automatically. These landmarks are then used for calculation of the ventricular shape, volume and size. A total of 20 brain ventricular systems were analyzed. The morphometric dimensions of the ventricles are presented in this paper. This study forms an initial basis for more advanced work on ventricular segmentation and morphometry.

  15. Patient selection for left ventricular assist devices.

    PubMed

    Lund, Lars H; Matthews, Jennifer; Aaronson, Keith

    2010-05-01

    Heart transplantation (HTx) improves symptoms and prolongs life in advanced heart failure (HF), but organ supply is limited. In recent years, mechanical circulatory support and specifically implantable left ventricular assist devices (LVADs) have undergone technical improvements, and outcomes have improved dramatically. Left ventricular assist devices are now viable options for patients with severe HF as bridge to transplantation, destination therapy, or as bridge to recovery. Many believe that LVADs may soon provide outcomes similar to, or better than, HTx, launching a new era of end-stage HF management. The key to improving outcomes is patient selection, but the field is changing rapidly and guidelines and consensus are limited. This review summarizes recent reports of predictors of poor outcomes and provides an overview of selection for LVAD therapy. PMID:20172939

  16. Ventricular assist device in univentricular heart physiology.

    PubMed

    Brancaccio, Gianluca; Gandolfo, Fabrizio; Carotti, Adriano; Amodeo, Antonio

    2013-04-01

    The use of mechanical cardiac assistance is well established as a bridge to orthotopic heart transplantation (OHT) or to recovery for patients with congestive heart failure, however, the experience in single ventricle (SV) physiology is still limited. We report two cases of mechanical assistance in patients with SV physiology: a 2-year old male with hypoplastic left heart syndrome who underwent Norwood Stage I and II followed by HF and a 4-year old female with a univentricular heart who developed a severe right ventricular dysfunction 2 years after a cavopulmonary shunt. Mechanical support utilizing ventricular assist devices (VADs) is considered a valid tool to bridge patients with congestive heart failure to either OHT or to recovery. Increasing experience and improved outcomes utilizing this technology in children with biventricular hearts have led to considering employing these devices in failing SV treatment. We present 2 cases of terminally ill children with SV who were assisted with a VAD.

  17. Catecholaminergic polymorphic ventricular tachycardia: a current overview.

    PubMed

    Leite, Luiz R; Henz, Benhur D; Macedo, Paula G; Santos, Simone N; Barreto, José R; Zanatta, André; Fenelon, Guilherme; Cruz Filho, Fernando E S

    2009-03-01

    Catecholaminergic polymorphic ventricular tachycardia occurs in healthy children and young adults causing syncope and sudden cardiac death. This is a familial disease, which affect de novo mutation in 50% of the cases. At least two causative genes have been described to be localized in the chromosome 1; mutation of the ryanodine receptor gene and calsequestrin gene. The classical clinical presentation is syncope triggered by exercise and emotion in children and adolescents with no structural heart disease. Polymorphic ventricular tachycardia during treadmill testing, or after isoproterenol infusion, is the most common feature. Therapeutic options include, beta-blockers, calcium-channel blockers and, an implantable cardioverter defibrillator is indicated in high-risk patients. Risk stratification of this disease is very challenging, since some risk factors proved to be useful in some series but not in others. However, family history of sudden cardiac death and symptoms initiated in very young children are important predictors.

  18. Ventricular fibrillation during sport activity successfully treated.

    PubMed

    Gonzalez, Maria Margarita; Marques, Flávio Rocha Brito; Vianna, Caio Brito; Eid, Carlos Alberto; Feitosa-Filho, Gilson Soares; Timerman, Sergio

    2009-08-01

    Survival after out-of-hospital cardiopulmonary arrest is estimated at less than 5%. We report a case of ventricular fibrillation during sports activity. Cardiopulmonary resuscitation was initiated early by a layperson, and defibrillation was successfully performed within less than three minutes, with an automated external defibrillator. The public access to defibrillation programs has increased the survival after out-of-hospital ventricular fibrillation. We should encourage the training of laypeople in relation to the use of automated external defibrillators and the Basic Life Support program by stimulating their implementation in places where large numbers of people gather or where people are at a high risk of sudden death, as is the case of sports centers.

  19. Youngest case of third ventricular anaplastic neurocytoma.

    PubMed

    Shravan Kumar, Chinnikatti; Sharma, D N; Sharma, Kuldeep; Haresh, K P; Rath, G K

    2010-04-01

    A 6-year-old child presented to us with on and off headache and vomiting for 4 months. On examination, there was bilateral papilledema with mild intracranial hypertension but with no neurological deficits. Magnetic resonance imaging (MRI) showed third ventricular mass with obstructive hydrocephalus with possibility of glioma. The patient underwent gross tumor excision and histopathology confirmed anaplastic neurocytoma. The postoperative MRI showed residual disease. The patient treated with adjuvant radiotherapy and temozolamide chemotherapy. PMID:21209769

  20. Youngest case of third ventricular anaplastic neurocytoma

    PubMed Central

    Shravan Kumar, Chinnikatti; Sharma, D. N.; Sharma, Kuldeep; Haresh, K. P.; Rath, G. K.

    2010-01-01

    A 6-year-old child presented to us with on and off headache and vomiting for 4 months. On examination, there was bilateral papilledema with mild intracranial hypertension but with no neurological deficits. Magnetic resonance imaging (MRI) showed third ventricular mass with obstructive hydrocephalus with possibility of glioma. The patient underwent gross tumor excision and histopathology confirmed anaplastic neurocytoma. The postoperative MRI showed residual disease. The patient treated with adjuvant radiotherapy and temozolamide chemotherapy. PMID:21209769

  1. [Ventricular fibrillation following deodorant spray inhalation].

    PubMed

    Girard, F; Le Tacon, S; Maria, M; Pierrard, O; Monin, P

    2008-01-01

    We report one case of out-of-hospital cardiac arrest with ventricular fibrillation following butane poisoning after inhalation of antiperspiration aerosol. An early management using semi-automatic defibrillator explained the success of the resuscitation. The mechanism of butane toxicity could be an increased sensitivity of cardiac receptors to circulating catecholamines, responsible for cardiac arrest during exercise and for resuscitation difficulties. The indication of epinephrine is discussed.

  2. Left ventricular heart failure and pulmonary hypertension†

    PubMed Central

    Rosenkranz, Stephan; Gibbs, J. Simon R.; Wachter, Rolf; De Marco, Teresa; Vonk-Noordegraaf, Anton; Vachiéry, Jean-Luc

    2016-01-01

    In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65–80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a ‘left ventricular phenotype’ to a ‘right ventricular phenotype’ across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context. PMID:26508169

  3. Ventricular assist devices: The future is now.

    PubMed

    Lima, Brian; Mack, Michael; Gonzalez-Stawinski, Gonzalo V

    2015-05-01

    Heart failure has become a global epidemic. For advanced heart failure, a broad assortment of device options have been introduced for both acute and prolonged intervals of hemodynamic assistance. Durable implantable ventricular assist devices (VADs) in particular play a key role in the management of advanced heart failure. This review focuses specifically on the current outcomes with VAD therapy, highlights the results from pivotal clinical trials, and summarizes the various device options on the market and those in preclinical development. PMID:25596799

  4. Salbutamol Abuse is Associated with Ventricular Fibrillation.

    PubMed

    Uysal, Emin; Solak, Suleyman; Carus, Murat; Uzun, Nedim; Cevik, Erdem

    2015-06-01

    Salbutamol-induced cardiac complications are well-established. Herein, we describe a case of a 24-year female who was admitted to the emergency department because of a suicide attempt with salbutamol (76 mg). Salbutamol abuse induced the development of supraventricular tachycardia and ventricular fibrillation. Regular sinus rhythm was restored with defibrillation. The hypokalemic patient who stayed in the intensive care unit was discharged after 48 hours of hospitalization. PMID:27336070

  5. Dynamic aortomyoplasty to assist left ventricular failure.

    PubMed

    Chachques, J C; Grandjean, P A; Cabrera Fischer, E I; Latremouille, C; Jebara, V A; Bourgeois, I; Carpentier, A

    1990-02-01

    The efficacy of skeletal muscle contractile force to augment left ventricular function has been demonstrated experimentally and clinically by the cardiomyoplasty procedure. Another approach in biomechanical cardiac assistance is the use of electrostimulated skeletal muscle in an extracardiac position. We describe an autologous counterpulsating device using the native ascending aorta as a ventricular chamber wrapped by an electrostimulated latissimus dorsi muscle flap (LDMF). This model avoids thrombotic complications observed in skeletal muscle neo-ventricles associated with prosthetic chambers. In 8 goats, a right LDMF was transferred to the thoracic cavity by removal of the second rib. In 4 goats, the diameter of the aorta was enlarged by surgical implantation (using lateral clamping) of an autologous pericardial patch. The LDMF was wrapped around the ascending aorta and electrostimulated using an external diastolic pulse generator connected to a sensing myocardial lead and to LDMF pacing electrodes. Hemodynamic studies were performed (left ventricular, aortic, and pulmonary artery pressures and rate of rise of left ventricular pressure). The LDMF diastolic counterpulsation was performed using a burst of 30 Hz, with a delay from the R wave adjusted to provide optimal diastolic augmentation. Percent increase in the subendocardial viability index was calculated during unassisted and assisted cardiac cycles (1:2) at baseline and after acute heart failure induced by the administration of high doses of propranolol hydrochloride (3 mg/kg intravenously). Diastolic aortic counterpulsation by the stimulated LDMF resulted in a significant improvement in the subendocardial viability index both at baseline and after induced cardiac failure in both groups, though the increase was greater in the group with aortic enlargement.

  6. Muscular Anatomy of the Human Ventricular Folds

    PubMed Central

    Moon, Jerald; Alipour, Fariborz

    2013-01-01

    Objective The purpose of this study was to better understand the muscular anatomy of the ventricular folds (VF) to help improve biomechanical modeling of phonation and to better understand the role of these muscles during phonatory and non-phonatory tasks. Method Four human larynges were decalcified and sectioned coronally from the posterior to anterior using a CryoJane tape transfer system, and stained using Massons trichrome. The total and relative area of muscles observed in each section were calculated and used for characterizing muscle distribution within the ventricular folds. Results The ventricular folds of the larynges contained anteriorly coursing thyroarytenoid and ventricularis muscle fibers lying in the lower half of the VF posteriorly, with some ventricularis muscle evident in the upper and lateral portion of the fold more anteriorly. Very little muscle tissue was observed in the medial half of the fold, and the anterior half of the VF was largely devoid of any muscle tissue. All four VF’s contained muscle bundles coursing superiorly and medially through the upper half of the fold toward the lateral margin of the epiglottis. Conclusions While variability in expression was evident, the well-defined thyroarytenoid muscle was readily apparent lateral to the arytenoid cartilage in all specimens. PMID:24224399

  7. Quantitative cineangiographic analysis of ventricular volume and mass in patients with single ventricle: relation to ventricular morphologies.

    PubMed

    Sano, T; Ogawa, M; Yabuuchi, H; Matsuda, H; Nakano, S; Shimazaki, Y; Taniguchi, K; Arisawa, J; Hirose, H; Kawashima, Y

    1988-01-01

    With the use of biplane selective ventriculography, the ventricular volume, ejection fraction, and ventricular mass were evaluated in 28 patients with a single ventricle, and those with the left ventricular type (LV type, 12 patients) and right ventricular type (RV type, 16 patients) were compared. There were no significant differences in terms of age, hemoglobin, systemic oxygen saturation, or pulmonary-to-systemic flow ratio in the two groups. No patients with atrioventricular valve regurgitation were included. The ventricular cavity volume was calculated by the area-length method. The ventricular mass volume was determined as the shell volume created by subtracting the ventricular cavity volume from the total ventricular volume calculated by adding the free wall thickness to the chamber dimensions. The ventricular mass volume was converted to mass by multiplying by the gravity of the heart muscle. There was no significant difference between patients with the LV type and RV type of single ventricle with respect to the end-diastolic ventricular volume (188 +/- 53 and 179 +/- 61 ml/m2 in LV and RV types, respectively), end-systolic volume (88 +/- 31 and 84 +/- 27 ml/m2), or ejection fraction (0.54 +/- 0.06 and 0.52 +/- 0.06).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3335072

  8. Amiodarone for the treatment and prevention of ventricular fibrillation and ventricular tachycardia

    PubMed Central

    Van Herendael, Hugo; Dorian, Paul

    2010-01-01

    Amiodarone has emerged as the leading antiarrhythmic therapy for termination and prevention of ventricular arrhythmia in different clinical settings because of its proven efficacy and safety. In patients with shock refractory out-of-hospital cardiac arrest and hemodynamically destabilizing ventricular arrhythmia, amiodarone is the most effective drug available to assist in resuscitation. Although the superiority of the transvenous implantable cardioverter defibrillator (ICD) over amiodarone has been well established in the preventive treatment of patients at high risk of life-threatening ventricular arrhythmias, amiodarone (if used with a beta-blocker) is the most effective antiarrhythmic drug to prevent ICD shocks and treat electrical storm. Both the pharmacokinetics and the electrophysiologic profile of amiodarone are complex, and its optimal and safe use requires careful patient surveillance with respect to potential adverse effects. PMID:20730062

  9. Are isolated wetlands isolated?

    USGS Publications Warehouse

    Smith, Loren M.; Euliss, Ned H.; Haukos, David A.

    2011-01-01

    While federal regulations during the past 10 years have treated isolated wetlands as unconnected to aquatic resources protected by the Clean Water Act, they provide critical ecosystem services to society that extend well beyond their wetland boundaries. The authors offer well-documented examples from the scientific literature on some of the ecosystem services provided by isolated wetlands to society and other ecosystems.

  10. A new electric method for non-invasive continuous monitoring of stroke volume and ventricular volume-time curves

    PubMed Central

    2012-01-01

    Background In this paper a new non-invasive, operator-free, continuous ventricular stroke volume monitoring device (Hemodynamic Cardiac Profiler, HCP) is presented, that measures the average stroke volume (SV) for each period of 20 seconds, as well as ventricular volume-time curves for each cardiac cycle, using a new electric method (Ventricular Field Recognition) with six independent electrode pairs distributed over the frontal thoracic skin. In contrast to existing non-invasive electric methods, our method does not use the algorithms of impedance or bioreactance cardiography. Instead, our method is based on specific 2D spatial patterns on the thoracic skin, representing the distribution, over the thorax, of changes in the applied current field caused by cardiac volume changes during the cardiac cycle. Since total heart volume variation during the cardiac cycle is a poor indicator for ventricular stroke volume, our HCP separates atrial filling effects from ventricular filling effects, and retrieves the volume changes of only the ventricles. Methods ex-vivo experiments on a post-mortem human heart have been performed to measure the effects of increasing the blood volume inside the ventricles in isolation, leaving the atrial volume invariant (which can not be done in-vivo). These effects have been measured as a specific 2D pattern of voltage changes on the thoracic skin. Furthermore, a working prototype of the HCP has been developed that uses these ex-vivo results in an algorithm to decompose voltage changes, that were measured in-vivo by the HCP on the thoracic skin of a human volunteer, into an atrial component and a ventricular component, in almost real-time (with a delay of maximally 39 seconds). The HCP prototype has been tested in-vivo on 7 human volunteers, using G-suit inflation and deflation to provoke stroke volume changes, and LVot Doppler as a reference technique. Results The ex-vivo measurements showed that ventricular filling caused a pattern over the

  11. Assessment and management of right ventricular failure in left ventricular assist device patients.

    PubMed

    Holman, William L; Acharya, Deepak; Siric, Franjo; Loyaga-Rendon, Renzo Y

    2015-01-01

    Mechanical circulatory support devices, including ventricular assist devices (VADs) and the total artificial heart, have evolved to become accepted therapeutic options for patients with severe congestive heart failure. Continuous-flow left VADs are the most prevalent option for mechanical circulatory assistance and reliably provide years of support. However, problems related to acute and chronic right heart failure in patients with left VADs continue to cause important mortality and morbidity. This review discusses the assessment and management of right ventricular failure in left VAD patients. The goal is to summarize current knowledge and suggest new approaches to managing this problem.

  12. Induction of ventricular collapse by an axial flow blood pump.

    PubMed

    Amin, D V; Antaki, J F; Litwak, P; Thomas, D; Wu, Z J; Watach, M

    1998-01-01

    An important consideration for clinical application of rotary blood pump based ventricular assist is the avoidance of ventricular collapse due to excessive operating speed. Because healthy animals do not typically demonstrate this phenomenon, it is difficult to evaluate control algorithms for avoiding suction in vivo. An acute hemodynamic study was thus conducted to determine the conditions under which suction could be induced. A 70 kg calf was implanted with an axial flow assist device (Nimbus/UoP IVAS; Nimbus Inc., Rancho Cordova, CA) cannulated from the left ventricular apex to ascending aorta. On initiation of pump operation, several vasoactive interventions were performed to alter preload, afterload, and contractility of the left ventricle. Initially, dobutamine increased contractility and heart rate ([HR] = 139; baseline = 70), but ventricular collapse was not achievable, even at the maximal pump speed of 15,000 rpm. Norepinephrine decreased HR (HR = 60), increased contractility, and increased systemic vascular resistance ([SVR] = 24; baseline = 15), resulting in ventricular collapse at a pump speed of 14,000 rpm. Isoproterenol (beta agonist) increased HR (HR = 103) and decreased SVR (SVR = 12), but ventricular collapse was not achieved. Inferior vena cava occlusion reduced preload, and ventricular collapse was achieved at speeds as low as 11,000 rpm. Esmolol (beta1 antagonist) decreased HR (HR = 55) and contractility, and ventricular collapse was achieved at 11,500 rpm. Episodes of ventricular collapse were characterized initially by the pump output exceeding the venous return and the aortic valve remaining closed throughout the cardiac cycle. If continued, the mitral valve would remain open throughout the cardiac cycle. Using these unique states of the mitral and aortic valves, the onset of ventricular collapse could reliably be identified. It is hoped that the ability to detect the onset of ventricular collapse, rather than the event itself, will assist in

  13. Right ventricular function before and after percutaneous balloon mitral valvuloplasty.

    PubMed

    Burger, W; Brinkies, C; Illert, S; Teupe, C; Kneissl, G D; Schräder, R

    1997-01-01

    Aim of this study was to evaluate right ventricular performance in patients with mitral stenosis and its modification by balloon valvuloplasty. Right ventricular volumes of 24 patients with postrheumatic mitral stenosis were determined by thermodilution 1 or 2 days before and 1 or 2 days after valvuloplasty. Right ventricular ejection fraction at rest was 43 (36-47)% (median and interquartile range). Right ventricular end-diastolic volume was 100 (86-119) ml/m2. Supine bicycle exercise (50 Watt) reduced right ventricular ejection fraction to 30 (29-37)% (P < 0.0001) and increased right ventricular end-diastolic volume to 124 (112-141) ml/m2 (P < 0.0001). At rest, right ventricular ejection fraction correlated inversely with pulmonary vascular resistance (r = -0.64, P < 0.0001), while no significant correlation with mitral valve area was found. Valvuloplasty increased right ventricular ejection fraction at rest to 48 (44-50)% (P < 0.005), and during exercise to 42 (38-45)% (P < 0.0001). This improvement of right ventricular ejection fraction correlated inversely with the value of this parameter before valvuloplasty (r = -0.88, P < 0.0001) and with the gain in stroke volume (r = 0.57, P < 0.01). The right ventricular function curve, disturbed before commissurotomy, was reestablished by the procedure. In conclusion, at the here investigated stage of mitral stenosis right ventricular function is reversibly impaired. This is predominantly caused by the hemodynamic consequences of the valvular defect and not by an impairment of right ventricular myocardial function.

  14. [Ventricular fibrillation following hyperventilation and apneic underwater swimming].

    PubMed

    Antonelli, Dante; Freedberg, Nahum A; Turgeman, Yoav

    2014-10-01

    This is a case study of an 18 years old boy who lost consciousness during apneic underwater swimming. When cardiopulmonary resuscitation was initiated ventricular fibrillation was seen on cardiac monitoring. Bradycardia, atrial and ventricular premature beats are a known response to hyperventilation and apneic underwater diving. This case is the first documentation of ventricular fibritllation as a cause of sudden cardiac death during apneic underwater swimming.

  15. Witten index for noncompact dynamics

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Joo; Yi, Piljin

    2016-06-01

    Among gauged dynamics motivated by string theory, we find many with gapless asymptotic directions. Although the natural boundary condition for ground states is L 2, one often turns on chemical potentials or supersymmetric mass terms to regulate the infrared issues, instead, and computes the twisted partition function. We point out how this procedure generically fails to capture physical L 2 Witten index with often misleading results. We also explore how, nevertheless, the Witten index is sometimes intricately embedded in such twisted partition functions. For d = 1 theories with gapless continuum sector from gauge multiplets, such as non-primitive quivers and pure Yang-Mills, a further subtlety exists, leading to fractional expressions. Quite unexpectedly, however, the integral L 2 Witten index can be extracted directly and easily from the twisted partition function of such theories. This phenomenon is tied to the notion of the rational invariant that appears naturally in the wall-crossing formulae, and offers a general mechanism of reading off Witten index directly from the twisted partition function. Along the way, we correct early numerical results for some of mathcal{N} = 4 , 8 , 16 pure Yang-Mills quantum mechanics, and count threshold bound states for general gauge groups beyond SU( N ).

  16. Genetic manipulation of periostin expression reveals a role in cardiac hypertrophy and ventricular remodeling.

    PubMed

    Oka, Toru; Xu, Jian; Kaiser, Robert A; Melendez, Jaime; Hambleton, Michael; Sargent, Michelle A; Lorts, Angela; Brunskill, Eric W; Dorn, Gerald W; Conway, Simon J; Aronow, Bruce J; Robbins, Jeffrey; Molkentin, Jeffery D

    2007-08-01

    The cardiac extracellular matrix is a dynamic structural support network that is both influenced by, and a regulator of, pathological remodeling and hypertrophic growth. In response to pathologic insults, the adult heart reexpresses the secreted extracellular matrix protein periostin (Pn). Here we show that Pn is critically involved in regulating the cardiac hypertrophic response, interstitial fibrosis, and ventricular remodeling following long-term pressure overload stimulation and myocardial infarction. Mice lacking the gene encoding Pn (Postn) were more prone to ventricular rupture in the first 10 days after a myocardial infarction, but surviving mice showed less fibrosis and better ventricular performance. Pn(-/-) mice also showed less fibrosis and hypertrophy following long-term pressure overload, suggesting an intimate relationship between Pn and the regulation of cardiac remodeling. In contrast, inducible overexpression of Pn in the heart protected mice from rupture following myocardial infarction and induced spontaneous hypertrophy with aging. With respect to a mechanism underlying these alterations, Pn(-/-) hearts showed an altered molecular program in fibroblast function. Indeed, fibroblasts isolated from Pn(-/-) hearts were less effective in adherence to cardiac myocytes and were characterized by a dramatic alteration in global gene expression (7% of all genes). These are the first genetic data detailing the function of Pn in the adult heart as a regulator of cardiac remodeling and hypertrophy. PMID:17569887

  17. A Computational Model of the Human Left-Ventricular Epicardial Myocyte

    PubMed Central

    Iyer, Vivek; Mazhari, Reza; Winslow, Raimond L.

    2004-01-01

    A computational model of the human left-ventricular epicardial myocyte is presented. Models of each of the major ionic currents present in these cells are formulated and validated using experimental data obtained from studies of recombinant human ion channels and/or whole-cell recording from single myocytes isolated from human left-ventricular subepicardium. Continuous-time Markov chain models for the gating of the fast Na+ current, transient outward current, rapid component of the delayed rectifier current, and the L-type calcium current are modified to represent human data at physiological temperature. A new model for the gating of the slow component of the delayed rectifier current is formulated and validated against experimental data. Properties of calcium handling and exchanger currents are altered to appropriately represent the dynamics of intracellular ion concentrations. The model is able to both reproduce and predict a wide range of behaviors observed experimentally including action potential morphology, ionic currents, intracellular calcium transients, frequency dependence of action-potential duration, Ca2+-frequency relations, and extrasystolic restitution/post-extrasystolic potentiation. The model therefore serves as a useful tool for investigating mechanisms of arrhythmia and consequences of drug-channel interactions in the human left-ventricular myocyte. PMID:15345532

  18. The physics of left ventricular ejection and its implications for muscle mechanics.

    PubMed

    Gordon, D G

    1976-05-01

    The ejection stage of the left ventricle of the heart is analyzed using the proper form of Newton's Second Law of Motion and a simple cylindrical ventricular model. The Laplace relation is then used to calculate the dynamic relationship between force, velocity and acceleration in an average, circumferential, equitorial myocardial wall fiber, yielding: Fm=Fa + Cacf + Dvcf2 where Fm is the force in the fiber, Fa the fiber force that would be required to match aortic pressure, acf the acceleration and vcf the velocity of shortening of the fiber. C is a constant, and D is a geometrical parameter that varies smoothly with time. The significance of the above equation is discussed both in terms of muscle function (total muscular force) and pump function afterload Fa and the differential force, Fm - Fa): The afterload component Fa provides the pressure head needed to force the blood through the capillaries (Poiseuille flow) and varies with time in accordance with the impedance of the vascular system (auxotonic loading). The differential component force Fm - Fa provides the ventricular impulse needed to overcome the inertia of the system due to (1) the mass of the blood, (2) the geometrical constriction of the outflow tract as one moves downstream (Bernoulli effect), and (2) the moving ventricular walls. Analysis of this sort should help in attempting to separate the intrinsic properties of cardiac muscle and the pump function of the intact heart. The important role that isolated muscle experiments can play in this effort is discussed.

  19. B-Type Natriuretic Peptide Levels Predict Ventricular Arrhythmia Post Left Ventricular Assist Device Implantation.

    PubMed

    Hellman, Yaron; Malik, Adnan S; Lin, Hongbo; Shen, Changyu; Wang, I-Wen; Wozniak, Thomas C; Hashmi, Zubair A; Pickrell, Jeanette; Jani, Milena; Caccamo, Marco A; Gradus-Pizlo, Irmina; Hadi, Azam

    2015-12-01

    B-type natriuretic peptide (BNP) levels have been shown to predict ventricular arrhythmia (VA) and sudden death in patients with heart failure. We sought to determine whether BNP levels before left ventricular assist device (LVAD) implantation can predict VA post LVAD implantation in advanced heart failure patients. We conducted a retrospective study consisting of patients who underwent LVAD implantation in our institution during the period of May 2009-March 2013. The study was limited to patients receiving a HeartMate II or HeartWare LVAD. Acute myocardial infarction patients were excluded. We compared between the patients who developed VA within 15 days post LVAD implantation to the patients without VA. A total of 85 patients underwent LVAD implantation during the study period. Eleven patients were excluded (five acute MI, four without BNP measurements, and two discharged earlier than 13 days post LVAD implantation). The incidence of VA was 31%, with 91% ventricular tachycardia (VT) and 9% ventricular fibrillation. BNP remained the single most powerful predictor of VA even after adjustment for other borderline significant factors in a multivariate logistic regression model (P < 0.05). BNP levels are a strong predictor of VA post LVAD implantation, surpassing previously described risk factors such as age and VT in the past. PMID:25864448

  20. Catheter ablation for ventricular tachyarrhythmias in patients supported by continuous-flow left ventricular assist devices.

    PubMed

    Garan, Arthur R; Iyer, Vivek; Whang, William; Mody, Kanika P; Yuzefpolskaya, Melana; Colombo, Paolo C; Te-Frey, Rosie; Takayama, Hiroo; Naka, Yoshifumi; Garan, Hasan; Jorde, Ulrich P; Uriel, Nir

    2014-01-01

    Ventricular arrhythmias (VAs) are common after implantation of a left ventricular assist device (LVAD) and in a subset of patients may be refractory to medication. Morbidity from VA in this population includes right ventricular failure (RVF). We sought to evaluate the efficacy of catheter ablation for VA in patients with LVAD. A retrospective analysis of patients supported by continuous-flow LVAD referred for catheter ablation of ventricular tachycardia (VT) between 2008 and the present was performed. Seven patients were referred for VT ablation an average of 236 ± 292 days after LVAD implantation. Three patients (42.9%) developed RVF in the setting of intractable arrhythmias. A transfemoral approach was used for six patients (85.7%) and an epicardial for one patient (14.3%). The clinical VT was inducible and successfully ablated in six patients (85.7%). The location of these arrhythmias was apical in three cases (42.9%). A total of 13 VTs were ablated in seven patients. Although the majority had reduction in VA frequency, recurrent VAs were observed in six patients (85.7%). One patient (14.3%) experienced a bleeding complication after the procedure. For patients with a high VA burden after LVAD implantation, VT ablation is safe and feasible, but VA frequently recurs.

  1. Conduction defects, ventricular arrhythmias, and late death after surgical closure of ventricular septal defect.

    PubMed Central

    Blake, R S; Chung, E E; Wesley, H; Hallidie-Smith, K A

    1982-01-01

    One hundred and eighty-seven patients who had surgical closure of a ventricular septal defect between 1958 and 1975 were followed for up to 21 years. there were 17 late sudden deaths of which eight occurred in completely fit patients while nine were already under medical care. In an attempt to elucidate possible risk factors and reoperative and serial postoperative electrocardiograms of all patients were studied. Fifty-one unselected healthy follow-up patients agreed to 24 hour ambulatory monitoring. Progressive exercise testing (Bruce protocol) was carried out on 31 of them and an additional seven patients. There was a significant correlation between recorded ventricular arrhythmias and conduction defects, particularly progressive conduction defects. Transient complete heart block carried a bad prognosis and grade 3-4b ventricular arrhythmias were a major risk factor and recorded in 10 of the 17 patients who died. Long-term postoperative electrocardiographic follow-up is recommended and 24 hour ambulatory monitoring and exercise testing complement the findings of the resting electrocardiogram. The long-term treatment of survivors found to have ventricular arrhythmias must be considered. PMID:7066115

  2. Hemodynamic effects of encainide in patients with ventricular arrhythmia and poor ventricular function

    SciTech Connect

    Sami, M.H.; Derbekyan, V.A.; Lisbona, R.

    1983-09-01

    Gated cardiac scanning was used to evaluate the hemodynamic effects of encainide in 19 patients (1 woman) with complex ventricular arrhythmia and depressed left ventricular (LV) function (ejection fraction less than 45%). Patients were 36 to 80 years old (average 61). All were candidates for long-term encainide therapy after having failed with currently available antiarrhythmics. Sixty-three percent had congestive heart failure before they received encainide. All were evaluated in the hospital before encainide therapy by a gated cardiac scan performed at least 3 days after discontinuing all antiarrhythmic drugs. Patients received oral encainide in doses of 75 to 200 mg. Gated cardiac scans were repeated 1 to 2 weeks later when an 80% reduction in frequency of premature ventricular complexes was observed on a 24-hour Holter recording. No patient had worsening of congestive heart failure during encainide therapy. Encainide did not significantly affect ejection fraction, which averaged 22 +/- 10% before and 25 +/- 14% (SD) after encainide (difference not significant (NS)). Other hemodynamic variables, including heart rate, blood pressure, stroke volume and end-diastolic volume, remained unchanged during encainide therapy. Digoxin blood levels in 10 patients averaged 1.04 +/- 0.43 before and 1.22 +/- 0.47 mg/ml (NS) during encainide therapy. Thus, encainide given orally in clinically effective doses does not appear to have significant hemodynamic effects in patients with ventricular arrhythmia and depressed LV function.

  3. Latent Left Ventricular Outflow Tract Obstruction Due to Accessory Mitral Valve in a 12-Year-Old Boy

    PubMed Central

    Yun, Kyung Won; Park, Yong Hyun; Lee, Sang Hyun; Kim, Jeong Su; Kim, June Hong; Chun, Kook Jin

    2016-01-01

    Accessory mitral valve (AMV) is a rare congenital anomaly which can cause left ventricular outflow tract (LVOT) obstruction. Patients with isolated AMV usually present with exertional dyspnea, chest pain, or syncope during the first ten years of life. In patients with AMV, detection of latent LVOT obstruction can be clinically challenging. We here present a case of AMV causing latent LVOT obstruction in an adolescent, which was diagnosed by echocardiography with dobutamine provocation and finally treated by successful surgical resection. PMID:27471367

  4. Ventricular shunt infections: immunopathogenesis and clinical management.

    PubMed

    Gutierrez-Murgas, Yenis; Snowden, Jessica N

    2014-11-15

    Ventricular shunts are the most common neurosurgical procedure performed in the United States. This hydrocephalus treatment is often complicated by infection of the device with biofilm-forming bacteria. In this review, we discuss the pathogenesis of shunt infection, as well as the implications of the biofilm formation on treatment and prevention of these infections. Many questions remain, including the contribution of glia and the impact of inflammation on developmental outcomes following infection. Immune responses within the CNS must be carefully regulated to contain infection while minimizing bystander damage; further study is needed to design optimal treatment strategies for these patients.

  5. [Recurrent failed ICD therapy of ventricular tachycardia].

    PubMed

    Hein, W; Ellringmann, U; Vollmann, D; Rostock, T; Schott, P

    2012-11-01

    Implantable cardioverter defibrillators (ICD) are used as standard therapy to prevent sudden cardiac death in heart failure patients. Today, physicians in emergency and intensive care medicine are often confronted with problems of ICD therapy in these patients. We report a case of a patient suffering from recurrent ventricular tachycardia (VT) requiring antiarrhythmia treatment with amiodarone. With an increasing drug loading, the VT cycle length was progressively prolonged resulting in a slow VT undetectable for the ICD. Subsequently, the patient was scheduled for VT ablation after which the patient became free of arrhythmia recurrences. PMID:23070331

  6. Left ventricular assist device management and complications.

    PubMed

    Birati, Edo Y; Rame, J Eduardo

    2014-07-01

    Patients on long-term left ventricular assist device (LVAD) support present unique challenges in the intensive care unit. It is crucial to know the status of end-organ perfusion, which may require invasive hemodynamic monitoring with a systemic arterial and pulmonary artery catheter. Depending on the indication for LVAD support (bridge to decision or cardiac transplantation vs destination therapy), it is important to readdress goals of care with the patient (if possible) and their family after major events have occurred that challenge the survival of the patient. PMID:24996611

  7. A Randomized Controlled Trial:Treatments on Infundibular Ventricular Septal Defect

    ClinicalTrials.gov

    2015-02-06

    Heart Septal Defects, Ventricular; Double Outlet Right Ventricle, Noncommitted VSD; Double Outlet Right Ventricle, Subaortic VSD; Double Outlet Right Ventricle, Subpulmonary VSD; Supracristal Ventricular Septal Defect

  8. Current-Voltage Relationship for Late Na(+) Current in Adult Rat Ventricular Myocytes.

    PubMed

    Clark, R B; Giles, W R

    2016-01-01

    It is now well established that the slowly inactivating component of the Na(+) current (INa-L) in the mammalian heart is a significant regulator of the action potential waveform. This insight has led to detailed studies of the role of INa-L in a number of important and challenging pathophysiological settings. These include genetically based ventricular arrhythmias (LQT 1, 2, and 3), ventricular arrhythmias arising from progressive cardiomyopathies (including diabetic), and proarrhythmic abnormalities that develop during local or global ventricular ischemia. Inhibition of INa-L may also be a useful strategy for management of atrial flutter and fibrillation. Many important biophysical parameters that characterize INa-L have been identified; and INa-L as an antiarrhythmia drug target has been studied extensively. However, relatively little information is available regarding (1) the ion transfer or current-voltage relationship for INa-L or (2) the time course of its reactivation at membrane potentials similar to the resting or diastolic membrane potential in mammalian ventricle. This chapter is based on our preliminary findings concerning these two very important physiological/biophysical descriptors for INa-L. Our results were obtained using whole-cell voltage clamp methods applied to enzymatically isolated rat ventricular myocytes. A chemical agent, BDF 9148, which was once considered to be a drug candidate in the Na(+)-dependent inotropic agent category has been used to markedly enhance INa-L current. BDF acts in a potent, selective, and reversible fashion. These BDF 9148 effects are compared and contrasted with the prototypical activator of INa-L, a sea anemone toxin, ATX II. PMID:27586292

  9. Current-Voltage Relationship for Late Na(+) Current in Adult Rat Ventricular Myocytes.

    PubMed

    Clark, R B; Giles, W R

    2016-01-01

    It is now well established that the slowly inactivating component of the Na(+) current (INa-L) in the mammalian heart is a significant regulator of the action potential waveform. This insight has led to detailed studies of the role of INa-L in a number of important and challenging pathophysiological settings. These include genetically based ventricular arrhythmias (LQT 1, 2, and 3), ventricular arrhythmias arising from progressive cardiomyopathies (including diabetic), and proarrhythmic abnormalities that develop during local or global ventricular ischemia. Inhibition of INa-L may also be a useful strategy for management of atrial flutter and fibrillation. Many important biophysical parameters that characterize INa-L have been identified; and INa-L as an antiarrhythmia drug target has been studied extensively. However, relatively little information is available regarding (1) the ion transfer or current-voltage relationship for INa-L or (2) the time course of its reactivation at membrane potentials similar to the resting or diastolic membrane potential in mammalian ventricle. This chapter is based on our preliminary findings concerning these two very important physiological/biophysical descriptors for INa-L. Our results were obtained using whole-cell voltage clamp methods applied to enzymatically isolated rat ventricular myocytes. A chemical agent, BDF 9148, which was once considered to be a drug candidate in the Na(+)-dependent inotropic agent category has been used to markedly enhance INa-L current. BDF acts in a potent, selective, and reversible fashion. These BDF 9148 effects are compared and contrasted with the prototypical activator of INa-L, a sea anemone toxin, ATX II.

  10. Changes in vascular properties, not ventricular properties, predominantly contribute to baroreflex regulation of arterial pressure.

    PubMed

    Sakamoto, Takafumi; Kakino, Takamori; Sakamoto, Kazuo; Tobushi, Tomoyuki; Tanaka, Atsushi; Saku, Keita; Hosokawa, Kazuya; Onitsuka, Ken; Murayama, Yoshinori; Tsutsumi, Takaki; Ide, Tomomi; Sunagawa, Kenji

    2015-01-01

    Baroreflex modulates both the ventricular and vascular properties and stabilizes arterial pressure (AP). However, how changes in those mechanical properties quantitatively impact the dynamic AP regulation remains unknown. We developed a framework of circulatory equilibrium, in which both venous return and cardiac output are expressed as functions of left ventricular (LV) end-systolic elastance (Ees), heart rate (HR), systemic vascular resistance (R), and stressed blood volume (V). We investigated the contribution of each mechanical property using the framework of circulatory equilibrium. In six anesthetized dogs, we vascularly isolated carotid sinuses and randomly changed carotid sinus pressure (CSP), while measuring the LV Ees, aortic flow, right and left atrial pressure, and AP for at least 60 min. We estimated transfer functions from CSP to Ees, HR, R, and V in each dog. We then predicted these parameters in response to changes in CSP from the transfer functions using a data set not used for identifying transfer functions and predicted changes in AP using the equilibrium framework. Predicted APs matched reasonably well with those measured (r2=0.85-0.96, P<0.001). Sensitivity analyses indicated that Ees and HR (ventricular properties) accounted for 14±4 and 4±2%, respectively, whereas R and V (vascular properties) accounted for 32±4 and 39±4%, respectively, of baroreflex-induced AP regulation. We concluded that baroreflex-induced dynamic AP changes can be accurately predicted by the transfer functions from CSP to mechanical properties using our framework of circulatory equilibrium. Changes in the vascular properties, not the ventricular properties, predominantly determine baroreflex-induced AP regulation. PMID:25362137

  11. 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.

  12. Echocardiographic assessment of ejection fraction in left ventricular hypertrophy

    PubMed Central

    Wandt, B; Bojo, L; Tolagen, K; Wranne, B

    1999-01-01

    OBJECTIVE—To investigate the value of Simpson's rule, Teichholz's formula, and recording of mitral ring motion in assessing left ventricular ejection fraction (EF) in patients with left ventricular hypertrophy.
DESIGN—Left ventricular ejection fraction calculated by Simpson's rule and by Techholz's formula and estimated by mitral ring motion was compared with values obtained by radionuclide angiography.
SETTING—Secondary referral centre.
PATIENTS—16 patients with left ventricular hypertrophy and a clinical diagnosis of hypertrophic cardiomyopathy or hypertension.
RESULTS—Calculation by Teichholz's formula overestimated left ventricular ejection fraction by 10% (p = 0.002) and estimation based on mitral ring motion—that is, long axis measurements—underestimated ejection fraction by 19% (p = 0.002), without significant correlation between ring motion and ejection fraction. There was no significant difference between mean values of ejection fraction calculated by Simpson's rule and measured by the reference method, but a considerable scatter about the regression line with a standard error of the estimate of 9.3 EF%.
CONCLUSIONS—In patients with left ventricular hypertrophy the ejection fraction, calculated by Teichholz's formula or Simpson's rule, is a poor measure of left ventricular function. When mitral ring motion is used for the assessment in these patients the function should be expressed in ways other than by the ejection fraction.


Keywords: left ventricular hypertrophy; ejection fraction; mitral ring motion; atrioventricular plane displacement PMID:10409535

  13. Right ventricular dysfunction in patients with septic shock.

    PubMed

    Dhainaut, J F; Lanore, J J; de Gournay, J M; Huyghebaert, M F; Brunet, F; Villemant, D; Monsallier, J F

    1988-01-01

    Using a rapid computerized thermodilution method, we examined the evolution of right ventricular performance in 23 patients with septic shock. Nine survived the episode of septic shock. The other 14 patients died of refractory circulatory shock. Significant right ventricular systolic dysfunction, defined as decreased ejection fraction (-39%) and right ventricular dilation (+38%) was observed in all patients with septic shock. However, in the survivors, increased right ventricular preload may prevent hemodynamic evidence of right ventricular pump failure by utilizing the Frank-Starling mechanism to maintain stroke volume. Conversely, in the nonsurvivors, right ventricular dysfunction was more prononced two days after the onset of septic shock, leading to a fall in stroke. In the last patients, a decrease in contractility appears to be the major factor accounting for decreased right ventricular performance, as evidenced by the marked increase in end-systolic volume (+27%) without significant change in pulmonary artery pressure, during the later stage of septic shock. The observed right ventricular pump failure then appears associated with an alteration in diastolic mechanical properties of this ventricle, as suggested by a leftward displacement of the individual pressure-volume curves. PMID:3403793

  14. Bradyarrhythmias: first presentation of arrhythmogenic right ventricular cardiomyopathy?

    PubMed

    Burghouwt, Danielle E; Kammeraad, Janneke Ae; Knops, Paul; du Plessis, Frederik A; de Groot, Natasja Ms

    2015-04-01

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disorder characterized by progressive replacement of myocardial cells by fibro-fatty tissue giving rise to ventricular tachyarrhythmias. In this case report, we describe a pediatric patient with sinoatrial arrests and second degree atrioventricular conduction block several years before ARVC became apparent. These findings suggest that bradyarrhythmias can also be the first expression of ARVC.

  15. Aortic coarctation, aneurysm, and ventricular dysfunction in an asymptomatic infant.

    PubMed

    García, Ana I; Aguilar, Juan M; García, Enrique

    2016-06-01

    Aortic arch coarctation with post-coarctation aneurysm is rare in infants. We present the case of an asymptomatic 3-month-old infant with severe left ventricular dysfunction in this setting. The patient underwent surgical repair, and the left ventricular ejection fraction improved to recovery the 4th post-operative month. PMID:26980403

  16. Left ventricular guidewire pacing for transcatheter aortic valve implantation.

    PubMed

    Guérios, Enio E; Wenaweser, Peter; Meier, Bernhard

    2013-12-01

    Previous reports prove the safety and efficacy of cardiac pacing employing a guidewire in the left ventricle as unipolar pacing electrode. We describe the use of left ventricular guidewire pacing as an alternative to conventional transvenous temporary right ventricular pacing in the context of transcatheter aortic valve implantation.

  17. Aortic coarctation, aneurysm, and ventricular dysfunction in an asymptomatic infant.

    PubMed

    García, Ana I; Aguilar, Juan M; García, Enrique

    2016-06-01

    Aortic arch coarctation with post-coarctation aneurysm is rare in infants. We present the case of an asymptomatic 3-month-old infant with severe left ventricular dysfunction in this setting. The patient underwent surgical repair, and the left ventricular ejection fraction improved to recovery the 4th post-operative month.

  18. Arrhythmogenic right ventricular dysplasia/cardiomyopathy in a Siberian husky.

    PubMed

    Fernández del Palacio, M J; Bernal, L J; Bayón, A; Bernabé, A; Montes de Oca, R; Seva, J

    2001-03-01

    A seven-month-old male Siberian husky was presented with a recent history of anorexia, hindlimb weakness and syncope. Physical examination revealed severe tachycardia, tachypnoea and dyspnoea. Mucous membranes were pale and femoral pulses were weak. An electrocardiogram showed sustained ventricular tachycardia with a left bundle branch block configuration. Thoracic radiographs revealed slight right ventricular enlargement and two-dimensional echocardiography revealed mild right ventricular dilation at the cardiac apex and some hyperechogenic areas on the right side of the interventricular septum. Administration of intravenous lignocaine converted the ventricular tachycardia to sinus rhythm. The maintenance antiarrhythmic therapy consisted of oral procainamide and propranolol. Three weeks later the dog died suddenly. On postmortem examination, the right ventricular free wall was very thin at the apex, infundibulum and caudal aspect of the right ventricular parietal wall, similar to the 'triangle of dysplasia' of human patients. Histopathological examination revealed replacement of several areas of right ventricular free wall myocardium with connective tissue and fat. The right atrium and left ventricle were less severely affected by the same lesions. The clinical and pathological findings are similar to those reported in young people with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

  19. Ultrasonic Sensors For Measuring Regional Ventricular Function

    NASA Astrophysics Data System (ADS)

    Hartley, C. J.; Rabinovitz, R. S.; Patel, B.; Suignard, L. J.; Litowitz, H.; Chelly, J. E.; Jeroudi, M. O.; Charlat, M. L.; O'Neill, P. G.; Noon, G. P.

    1988-04-01

    Measurement of systolic wall thickening by sonomicrometry is an accurate index of regional left ventricular (LV) function, but the trauma of crystal inserion precludes its clinical use. We have developed a 4-mm 10 MHz ultrasonic probe which can either be sutured or applied via suction to the epicar-diuui and can measure wall thickening at anv depth of the LV wall. In 18 dogs, the suction probe correlated well (r=0.97) with previously validated sutured probe. To assess clinical feasibility, the probe was applied to the epicardium of 45 patients undergoing coronary bypass surgery. Good wall thickening tracings were obtained with no trauma. Transmural LV thickening fraction prior to bypass surgery was 32 ± 6 % (X ± SEM) at the midventricular lateral wall, 29 ± 5 % at the anterior basal wall and 25 ± 5 % at the midventricular posterior wall. Right ventricular thickening fraction averaged 25 ± 4 %. In general, wall thickening during immediate postoperative period remained unchanged compared to preoperative thickening fraction. Exteriorization of a wire attached to the sutured probe allows in situ monitoring of wall thickening for 48-72 h after surgery and subsequent removal. Thus, this probe is an accurate, atraumatic method for measuring right and LV regional function. Transmural, endocardial and epicardial function can be mapped at various sites during surgery and post-operatively one can follow serial changes of regional function and assess the effects of cardioplegia and other therapeutic interventions.

  20. ECG manifestations of left ventricular electrical remodeling.

    PubMed

    Estes, E Harvey

    2012-01-01

    Research and thinking about the electrocardiographic manifestations of left ventricular hypertrophy has been constrained by a limited conceptual model of the process: heart disease produces chamber enlargement (increased mass), which in turn produces an altered electrocardiogram. The process is much more complex than can be represented in this simple model. A more robust and intricate model is proposed, in which heart (and vascular) disease causes structural changes, electrical changes, biochemical changes, and others, all of which interact to produce electrical remodeling of ventricular myocardium. This electrical remodeling results in a variety of ECG changes. All of these changes interact, leading to an altered clinical course, and to premature death. It is suggested that research, based on this model, can provide new clues to the processes involved, and improve the prediction of clinical outcomes. New directions in research, in recording equipment, and in organizational activities are suggested to test this new model, and to improve the usefulness of the electrocardiogram as a research and diagnostic tool.

  1. Distinct loading conditions reveal various patterns of right ventricular adaptation.

    PubMed

    Borgdorff, Marinus A J; Bartelds, Beatrijs; Dickinson, Michael G; Steendijk, Paul; de Vroomen, Maartje; Berger, Rolf M F

    2013-08-01

    Right ventricular (RV) failure due to chronically abnormal loading is a main determinant of outcome in pulmonary hypertension (PH) and congenital heart disease. However, distinct types of RV loading have been associated with different outcomes. To determine whether the adaptive RV response depends on loading type, we compared hemodynamics, exercise, and hypertrophy in models of pressure overload due to pulmonary artery banding (PAB), pressure overload due to PH, combined pressure and volume overload, and isolated volume load. Ninety-four rats were subjected to either PAB, monocrotaline-induced PH (PH), aortocaval shunt (shunt), or combined monocrotaline and aortocaval shunt (PH + shunt). We performed pressure-volume analysis and voluntary exercise measurements at 4 wk. We compared PAB to PH (part I) and PH + shunt to either isolated PH or shunt (part II). In part I, enhanced contractility (end-systolic elastance and preload recruitable stroke work) was present in PH and PAB, but strongest in PAB. Frank-Starling mechanism was active in both PAB and PH. In PAB this was accompanied by diastolic dysfunction (increased end-diastolic elastance, relaxation constant), clinical signs of RV failure, and reduced exercise. These distinct responses were not attributable to differences in hypertrophy. In part II, in PH + shunt the contractility response was blunted compared with PH, which caused pseudonormalization of parameters. Additional volume overload strongly enhanced hypertrophy in PH. We conclude that different types of loading result in distinct patterns of RV adaptation. This is of importance for the approach to patients with chronically increased RV load and for experimental studies in various types of RV failure.

  2. The electrocardiographic diagnosis of intraventricular blocks coexisting with ventricular preexcitation.

    PubMed

    Chiale, Pablo A; Elizari, Marcelo V

    2012-09-01

    The electrocardiographic diagnosis of intraventricular conduction disturbances may be hindered by the coexistence of ventricular preexcitation. In fact, the premature depolarization of ventricular myocardium through an accessory pathway tends to conceal any electrocardiographic manifestation of a bundle-branch block. However, there are several conditions favoring the diagnosis of bundle-branch block associated with ventricular preexcitation: intermittency of ventricular preexcitation and/or bundle-branch block, fast atrioventricular (AV) nodal impulse propagation, slow conduction over the accessory pathway or between its ventricular insertion site and the remaining myocardium, and presence of atrioventricular junctional ectopic beats exposing the intraventricular conduction disturbance. This article reexamines the available data on preexcitation in patients with intraventricular blocks and presents clinical examples to emphasize the importance of a thorough examination of the electrocardiogram to attain the correct diagnosis of this association.

  3. Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal.

    PubMed

    Abu Saleh, Walid K; Al Jabbari, Odeaa; Bruckner, Brian A; Suarez, Erik E; Estep, Jerry D; Loebe, Matthias

    2015-08-01

    Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device. PMID:26234850

  4. Left Ventricular Assist Device Implantation After Intracardiac Parachute Device Removal.

    PubMed

    Abu Saleh, Walid K; Al Jabbari, Odeaa; Bruckner, Brian A; Suarez, Erik E; Estep, Jerry D; Loebe, Matthias

    2015-08-01

    Left ventricular assist device implantation is a proven and efficient modality for the treatment of end-stage heart failure. Left ventricular assist device versatility as a bridge to heart transplantation or destination therapy has led to improved patient outcomes with a concomitant rise in its overall use. Other less invasive treatment modalities are being developed to improve heart function and morbidity and mortality for the heart failure population. Percutaneous ventricular restoration is a new investigational therapy that deploys an intracardiac parachute to wall off damaged myocardium in patients with dilated left ventricles and ischemic heart failure. Clinical trials are under way to test the efficacy of percutaneous ventricular restoration using the parachute device. This review describes our encounter with the parachute device, its explantation due to refractory heart failure, and surgical replacement with a left ventricular assist device.

  5. A case of premature ventricular contractions, ventricular tachycardia, and arrhythmic storm induced by right ventricular pacing during cardiac resynchronization therapy: Electrophysiological mechanism and catheter ablation

    PubMed Central

    Pedretti, Stefano; Vargiu, Sara; Paolucci, Marco; Lunati, Maurizio

    2015-01-01

    A 77-year-old man with ischemic cardiomyopathy and a cardiac resynchronization therapy-defibrillator (CRT-D) device came to our attention due to incessant ventricular tachycardia and multiple implantable cardioverter defibrillator (ICD) shocks. An electrocardiogram showed non-sustained monomorphic ventricular tachycardias (NSVTs) constantly occurring after each biventricular stimulation. During an electrophysiological study, NSVTs reproducibly recurred only after right ventricular (RV) pacing; LV pacing did not induce any NSVTs. The activation map was consistent with a localized reentry at the interventricular septum, and a double exit; at the LV exit site, a single radiofrequency energy application immediately interrupted the occurrence of the NSVTs. Current evidence supports LV pacing to be pro-arrhythmogenic in few CRT patients. This unusual case shows that RV pacing during CRT could produce frequent ventricular arrhythmias and arrhythmic storm. Catheter ablation can be considered an effective therapeutic option, especially when CRT maintenance is highly advisable. PMID:26702324

  6. [Ventricular activation sequence estimated by body surface isochrone map].

    PubMed

    Hayashi, H; Ishikawa, T; Takami, K; Kojima, H; Yabe, S; Ohsugi, S; Miyachi, K; Sotobata, I

    1985-06-01

    This study was performed to evaluate the usefulness of the body surface isochrone map (VAT map) for identifying the ventricular activation sequence, and it was correlated with the isopotential map. Subjects consisted of 42 normal healthy adults, 18 patients with artificial ventricular pacemakers, and 100 patients with ventricular premature beats (VPB). The sites of pacemaker implantations were the right ventricular endocardial apex (nine cases), right ventricular epicardial apex (five cases), right ventricular inflow tract (one case), left ventricular epicardial apex (one case), and posterior base of the left ventricle via the coronary sinus (two cases). An isopotential map was recorded by the mapper HPM-6500 (Chunichi-Denshi Co.) on the basis of an 87 unipolar lead ECG, and a VAT isochrone map was drawn by a minicomputer. The normal VAT map was classified by type according to alignment of isochrone lines, and their frequency was 57.1% for type A, 16.7% for type B, and 26.2% for type C. In the VAT map of ventricular pacing, the body surface area of initial isochrone lines represented well the sites of pacemaker stimuli. In the VAT map of VPB, the sites of origin of VPB agreed well with those as determined by the previous study using an isopotential map. The density of the isochrone lines suggested the mode of conduction via the specialized conduction system or ventricular muscle. The VAT map is a very useful diagnostic method to predict the ventricular activation sequence more directly in a single sheet of the map. PMID:2419457

  7. Nipro extra-corporeal left ventricular assist device fitting after left ventricular reconstruction with mitral valve plasty.

    PubMed

    Arakawa, Mamoru; Yamaguchi, Atsushi; Nishimura, Takashi; Itoh, Satoshi; Yuri, Koichi; Kyo, Shunei; Adachi, Hideo

    2015-12-01

    Both left ventricular assist device and left ventricular reconstruction are treatment choices for severe heart failure conditions. Our institution performed a left ventricular assist device installation following a left ventricular reconstruction procedure on a 42-year-old male patient who presented with dilated cardiomyopathy and low cardiac output syndrome. A mitral valve plasty was used to correct the acute mitral valve regurgitation and we performed a Nipro extra-corporeal left ventricular assist device installation on post-operative day 14. Due to the left ventricular reconstruction that the patient had in a previous operation, we needed to attach an apical cuff on posterior apex, insert the inflow cannula with a large curve, and shift the skin insertion site laterally to the left. We assessed the angle between the cardiac longitudinal axis and the inflow cannula using computed tomography. The patient did not complain of any subjective symptoms of heart failure. Although Nipro extra-corporeal left ventricular assist device installation after left ventricular reconstruction has several difficulties historically, we have experienced a successful case.

  8. Relationship of ventricular arrhythmias to the angiographically and scintigraphically estimated extent of ventricular damage late after myocardial infarction

    SciTech Connect

    Huikuri, H.V.; Korhonen, U.R.; Linnaluoto, M.K.; Takkunen, J.T.

    1987-03-01

    In order to study the quantitative relationship of ventricular arrhythmias to myocardial damage and ischemia, 61 patients with a previous myocardial infarction (at least 6 months previously) were studied by 24-hour ambulatory ECG monitoring, cardiac catheterization, and thallium-201 scintigraphy. Thirty-five patients (57%) had no ectopic beats or only infrequent, unifocal ones and 26 patients (43%) had complex ventricular arrhythmias. Left ventricular function was lower in the latter, but the number of diseased vessels did not differ in the two groups. The reduction of thallium activity in the infarct area was more marked in patients with complex arrhythmias. Multiple thallium defects were not more common in arrhythmia patients, however. These data support the view that complex ventricular arrhythmias are more closely related to the severity of ventricular damage than the presence of myocardial ischemia remote to the area of previous infarction.

  9. Risk factors predictive of right ventricular failure after left ventricular assist device implantation.

    PubMed

    Drakos, Stavros G; Janicki, Lindsay; Horne, Benjamin D; Kfoury, Abdallah G; Reid, Bruce B; Clayson, Stephen; Horton, Kenneth; Haddad, Francois; Li, Dean Y; Renlund, Dale G; Fisher, Patrick W

    2010-04-01

    Right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation appears to be associated with increased mortality. However, the determination of which patients are at greater risk of developing postoperative RVF remains controversial and relatively unknown. We sought to determine the preoperative risk factors for the development of RVF after LVAD implantation. The data were obtained for 175 consecutive patients who had received an LVAD. RVF was defined by the need for inhaled nitric oxide for >/=48 hours or intravenous inotropes for >14 days and/or right ventricular assist device implantation. An RVF risk score was developed from the beta coefficients of the independent variables from a multivariate logistic regression model predicting RVF. Destination therapy (DT) was identified as the indication for LVAD implantation in 42% of our patients. RVF after LVAD occurred in 44% of patients (n = 77). The mortality rates for patients with RVF were significantly greater at 30, 180, and 365 days after implantation compared to patients with no RVF. By multivariate logistic regression analysis, 3 preoperative factors were significantly associated with RVF after LVAD implantation: (1) a preoperative need for intra-aortic balloon counterpulsation, (2) increased pulmonary vascular resistance, and (3) DT. The developed RVF risk score effectively stratified the risk of RV failure and death after LVAD implantation. In conclusion, given the progressively growing need for DT, the developed RVF risk score, derived from a population with a large percentage of DT patients, might lead to improved patient selection and help stratify patients who could potentially benefit from early right ventricular assist device implantation. PMID:20346326

  10. Large Right Ventricular Clot in Pulmonary Atresia With Intact Ventricular Septum: In Defense of Biventricular Approach.

    PubMed

    Dutta, Nilanjan; Ghosh, Rajarshi; Awasthy, Neeraj; Iyer, Parvathi U; Girotra, Sumir; Iyer, Krishna S

    2016-09-01

    Thrombus formation within the right ventricle (RV) in the setting of pulmonary atresia with intact ventricular septum (PAIVS) is not a very common occurrence and can be catastrophic. We present the case of a seven-month-old child with PAIVS and RV clot who successfully underwent biventricular repair. We discuss the interesting case and the rationale for management by means of biventricular repair over single ventricle repair when feasible in such a setting.

  11. Electrophysiologic features of fetal ventricular aneurysms and diverticula

    PubMed Central

    PETERS, CARLI; WACKER-GUSSMANN, ANNETTE; STRASBURGER, JANETTE F; CUNEO, BETTINA F; GOTTEINER, NINA; GULECYUZ, MEHEMET; WAKAI, RONALD T

    2014-01-01

    Objective Congenital ventricular wall defects are very rare and include congenital ventricular aneurysms (CVAs) and diverticula (CVDs). Method We report a series of five fetuses: three with CVAs and two with CVDs referred due to fetal arrhythmia. In addition to routine fetal echocardiography, fetal magnetocardiography (fMCG) was used. The literature in CVA and CVD is reviewed. Results Incessant premature ventricular contractions (PVC), mainly bigeminy and trigeminy were found in three fetuses with CVAs and in one with CVD, who also had ventricular couplets. The other fetus with CVD, referred because of PVCs, had only sinus tachycardia. ST elevation was noted in two. Fetal movement had a variable impact on PVC’s. Postnatal evaluation demonstrated two persistent left ventricular aneurysms and one persistent right CVD; one CVD resolved at 35 weeks gestation. Two neonates had incessant PVCs. Both arrhythmias resolved spontaneously while being treated with propranolol. Conclusion FMCG is complementary to echocardiographic imaging. In fetuses with left ventricular wall defects, additional electrophysiological diagnosis can be made by fMCG, including the complexity of ventricular ectopy, arrhythmic response to fetal movement, presence of ST-T wave abnormalities, and atrial amplitude increases. Prenatal risk factor assessment using fMCG can additionally support post-natal treatment and follow-up. PMID:25284224

  12. Tricuspid atresia: analysis of coronary artery distribution and ventricular morphology.

    PubMed Central

    Deanfield, J E; Tommasini, G; Anderson, R H; Macartney, F J

    1982-01-01

    There is still disagreement concerning the precise nature of the anterior ventricular chamber in "tricuspid atresia". Some argue that it is a right ventricle, while our own previous studies have suggested it is comparable to the outlet chamber seen in classical "single ventricle". We have compared the morphology of the anterior ventricular chambers in 48 examples of tricuspid atresia (absent right atrioventricular connection), 24 hearts with double inlet to the left ventricular chamber, and 15 hearts with pulmonary atresia and intact ventricular septum. Since there is further disagreement concerning the nature of the coronary artery which delimits the posterior extent of the ventricular septum in these hearts, we analysed the position of this vessel relative to external reference points on the atrioventricular junction. No significant difference was found with respect to the morphometry of hearts with tricuspid atresia (absent right atrioventricular connection) and those with double inlet. In both groups, however, significant differences were shown between hearts with ventriculoarterial concordance and discordance. Coronary artery disposition was the same in both groups and different from that found in hearts with pulmonary atresia and intact septum. We conclude that the ventricular morphology is comparable in hearts with tricuspid atresia (absent right atrioventricular connection) and those with double inlet to a left ventricular chamber. The lesions are distinguishable by their atrioventricular connection which is nevertheless univentricular in both. Images PMID:7138712

  13. The Multiple Electrocardiographic Manifestations of Ventricular Repolarization Memory

    PubMed Central

    Chiale, Pablo A; Etcheverry, Daniel; Pastori, Julio D; Fernández, Pablo A; Garro, Hugo A; González, Mario D; Elizari, Marcelo V

    2014-01-01

    T wave “memory” is a peculiar variety of cardiac remodeling caused by a transient change in the course of ventricular depolarization (due to ventricular pacing, rate-dependent intraventricular block, ventricular preexcitation or tachyarrhythmias with wide QRS complexes). It is usually manifested by inverted T waves that appears when normal ventricular activation is restored. This phenomenon is cumulative and occurs earlier if the ventricular myocardium has previously been exposed to the same conditioning stimuli. In this article the different conditions giving rise to “classical” T wave memory development are reviewed and also “another” type of T wave memory is described. It is also shown that cardiac memory may induce not only negative (pseudo-primary) T waves but also a reversal of primary and pseudo-primary T waves leading to “normalization” of ventricular repolarization. The knowledge of these dissimilar consequences of T wave memory is essential to assess the characteristics of ventricular repolarization. PMID:24827802

  14. Risk factors for asymptomatic ventricular dysfunction in rheumatoid arthritis patients.

    PubMed

    Garza-García, Carlos; Rocío, Sánchez-Santillán; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Eduardo, Canseco; López-Campos, José Luis; Keirns-Davis, Candace

    2013-01-01

    Objective. The aim of the study was to describe echocardiographic abnormalities in patients with rheumatoid arthritis, concurrent systemic comorbidities, rheumatologic clinical activity, serologic markers of rheumatoid arthritis, and inflammatory activity. Methods. In an observational, cross-sectional study, rheumatoid arthritis outpatients were included (n = 105). Conventional transthoracic echocardiographic variables were compared between patients with arthritis and non-RA controls (n = 41). For rheumatoid arthritis patients, articular activity and rheumatologic and inflammatory markers were obtained. Results. Ventricular dysfunction was found in 54.3% of the population: systolic (18.1%), diastolic (32.4%), and/or right (24.8%), with lower ejection fraction (P < 0.0001). Pulmonary hypertension was found in 46.9%. Other echocardiographic findings included increased left atrial diameter (P = 0.01), aortic diameter (P = 0.01), ventricular septum (P = 0.01), left ventricular posterior wall (P = 0.013), and right ventricular (P = 0.01) and atrial diameters compared to control subjects. Rheumatoid factor and anti-CCP antibodies levels were significantly elevated in cases with ventricular dysfunction. Angina and myocardial infarction, diabetes, and dyslipidemia were the main risk factors for ventricular dysfunction. Conclusions. Ventricular dysfunction is common in rheumatoid arthritis and associated with longer disease duration and increased serologic markers of rheumatoid arthritis. Screening for cardiac abnormalities should be considered in this kind of patients.

  15. Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

    PubMed

    Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

    2014-04-01

    Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator.

  16. Risk Factors for Asymptomatic Ventricular Dysfunction in Rheumatoid Arthritis Patients

    PubMed Central

    Garza-García, Carlos; Rocío, Sánchez-Santillán; Orea-Tejeda, Arturo; Castillo-Martínez, Lilia; Eduardo, Canseco; López-Campos, José Luis; Keirns-Davis, Candace

    2013-01-01

    Objective. The aim of the study was to describe echocardiographic abnormalities in patients with rheumatoid arthritis, concurrent systemic comorbidities, rheumatologic clinical activity, serologic markers of rheumatoid arthritis, and inflammatory activity. Methods. In an observational, cross-sectional study, rheumatoid arthritis outpatients were included (n = 105). Conventional transthoracic echocardiographic variables were compared between patients with arthritis and non-RA controls (n = 41). For rheumatoid arthritis patients, articular activity and rheumatologic and inflammatory markers were obtained. Results. Ventricular dysfunction was found in 54.3% of the population: systolic (18.1%), diastolic (32.4%), and/or right (24.8%), with lower ejection fraction (P < 0.0001). Pulmonary hypertension was found in 46.9%. Other echocardiographic findings included increased left atrial diameter (P = 0.01), aortic diameter (P = 0.01), ventricular septum (P = 0.01), left ventricular posterior wall (P = 0.013), and right ventricular (P = 0.01) and atrial diameters compared to control subjects. Rheumatoid factor and anti-CCP antibodies levels were significantly elevated in cases with ventricular dysfunction. Angina and myocardial infarction, diabetes, and dyslipidemia were the main risk factors for ventricular dysfunction. Conclusions. Ventricular dysfunction is common in rheumatoid arthritis and associated with longer disease duration and increased serologic markers of rheumatoid arthritis. Screening for cardiac abnormalities should be considered in this kind of patients. PMID:24368945

  17. Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

    PubMed

    Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

    2014-04-01

    Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator. PMID:24780127

  18. Effects of ventricular insertion sites on rotational motion of left ventricular segments studied by cardiac MR

    PubMed Central

    Robson, M D; Rider, O J; Pegg, T J; Dasanu, C A; Jung, B A; Clarke, K; Holloway, C J

    2013-01-01

    Objective: Obtaining new details for rotational motion of left ventricular (LV) segments using velocity encoding cardiac MR and correlating the regional motion patterns to LV insertion sites. Methods: Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Peak rotational velocities and circumferential velocity curves were obtained for 16 ventricular segments. Results: Reduced peak clockwise velocities of anteroseptal segments (i.e. Segments 2 and 8) and peak counterclockwise velocities of inferoseptal segments (i.e. Segments 3 and 9) were the most prominent findings. The observations can be attributed to the LV insertion sites into the right ventricle, limiting the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments as viewed from the apex. Relatively lower clockwise velocities of Segment 5 and counterclockwise velocities of Segment 6 were also noted, suggesting a cardiac fixation point between these two segments, which is in close proximity to the lateral LV wall. Conclusion: Apart from showing different rotational patterns of LV base, mid ventricle and apex, the study showed significant differences in the rotational velocities of individual LV segments. Correlating regional wall motion with known orientation of myocardial aggregates has also provided new insights into the mechanisms of LV rotational motions during a cardiac cycle. Advances in knowledge: LV insertion into the right ventricle limits the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments adjacent to the ventricular insertion sites. The pattern should be differentiated from wall motion abnormalities in cardiac pathology. PMID:24133098

  19. Reverse ventricular remodeling and improved ventricular compliance after heart transplantation in infants and young children.

    PubMed

    Farooqi, Kanwal M; Lopez, Leo; Pass, Robert H; Hsu, Daphne T; Lamour, Jacqueline M

    2014-08-01

    After heart transplantation (HT) in infants and young children, environmental and intrinsic factors may lead to changes in the geometry and compliance of the donor heart. Serial demographic, clinical, hemodynamic, and echocardiographic data were obtained from HT recipients younger than 4 years of age. Echocardiographic chamber measurement z-scores were compared using recipient body surface area from the time of HT to 1 week, 3 months, and last follow-up visit. Left ventricular end-diastolic volume (LVEDV) z-scores were correlated with pulmonary capillary wedge pressure (PCWP) at each time point. Heart transplantation was performed for 13 children between March 2009 and December 2012, 9 of whom (69%) were boys. The median age at HT was 8 months (range, 4-43 months), and the mean follow-up period was 13 ± 7 months. Left ventricular end-diastolic dimension z-scores decreased significantly (p = 0.03) between HT and 1 week, then increased from 1 week to 3 and 12 months. (-1.32 ± 1.7, -0.71 ± 1.8, 0.41 ± 2.1, 0.79 ± 2.3, respectively). A positive relationship (R(2) = 0.48) between the LVEDV z-score and PCPW was present at the last follow-up visit. For infants and young children, the allograft demonstrates appropriate growth by 1 year after HT. Left ventricular compliance improves over time.

  20. Ventricular assist devices in the adult.

    PubMed

    Richards, Nancy M; Stahl, Mary A

    2007-01-01

    Ventricular assist devices (VADs) play an increasingly important role in the care of cardiovascular patients. Developed initially for support of cardiothoracic surgery patients experiencing difficulty in weaning from cardiopulmonary bypass, these devices have been used extensively as a bridge to cardiac transplantation for patients who are failing on medical management. Research has demonstrated the effectiveness of a VAD as destination therapy, providing a permanent means of support for patients with advanced heart failure who are not eligible for heart transplantation. Applications for VADs are expanding and advances in technology occurring to support these new applications. This article provides an overview of current and emerging VADs and nursing management of the VAD patient. PMID:17356352

  1. Endocarditis in left ventricular assist device

    PubMed Central

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-01-01

    Summary Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement.

  2. Integrative modeling of the cardiac ventricular myocyte

    PubMed Central

    Winslow, Raimond L.; Cortassa, Sonia; O'Rourke, Brian; Hashambhoy, Yasmin L.; Rice, John Jeremy; Greenstein, Joseph L.

    2011-01-01

    Cardiac electrophysiology is a discipline with a rich 50-year history of experimental research coupled with integrative modeling which has enabled us to achieve a quantitative understanding of the relationships between molecular function and the integrated behavior of the cardiac myocyte in health and disease. In this paper, we review the development of integrative computational models of the cardiac myocyte. We begin with a historical overview of key cardiac cell models that helped shape the field. We then narrow our focus to models of the cardiac ventricular myocyte and describe these models in the context of their subcellular functional systems including dynamic models of voltage-gated ion channels, mitochondrial energy production, ATP-dependent and electrogenic membrane transporters, intracellular Ca dynamics, mechanical contraction, and regulatory signal transduction pathways. We describe key advances and limitations of the models as well as point to new directions for future modeling research. PMID:20865780

  3. Right Ventricular Dysfunction During Intensive Pharmacologic Unloading Persists After Mechanical Unloading

    PubMed Central

    Palardy, Maryse; Nohria, Anju; Rivero, Jose; Lakdawala, Neal; Campbell, Patricia; Kato, Mahoto; Griffin, Leslie M.; Smith, Colleen M.; Couper, Gregory S.; Stevenson, Lynne W.; Givertz, Michael M.

    2014-01-01

    Background Right ventricular (RV) dysfunction is associated with adverse outcomes in heart failure (HF). Mechanical unloading should be more effective than pharmacologic therapy to reduce RV afterload and improve RV function. We compared RV size and function after aggressive medical unloading therapy to that achieved in the same patients after 3 months of left ventricular assist device (LVAD) support. Methods and Results We studied twenty patients who underwent isolated LVAD placement (9 pulsatile and 11 axial flow). Echocardiograms were performed after inpatient optimization with diuretic and inotropic therapy and compared to studies done after 3 months of LVAD support. After medical optimization right atrial pressure was 11±5 mm Hg, mean pulmonary artery pressure 36±11 mm Hg, pulmonary capillary wedge pressure 23±9 mm Hg, and cardiac index 2.0±0.6 L/min/m2. Pre-operatively, RV dysfunction was moderate (2.6 ±0.9 on 0-4 scale), RV diameter at the base was 3.1±0.6 cm, and mid-RV was 3.5±0.6 cm. After median LVAD support of 123 days (92-170), RV size and global RV dysfunction (2.6 ±0.9) failed to improve, despite reduced RV afterload. Conclusions RV dysfunction seen on intensive medical therapy persisted after 3 months of LVAD unloading therapy. Selection of candidates for isolated LV support should anticipate persistence of RV dysfunction observed on inotropic therapy. PMID:20206896

  4. Metastatic right ventricular mass with intracavitary obliteration

    PubMed Central

    Kalvakuri, Kavitha; Banga, Sandeep; Upalakalin, Nalinee; Shaw, Crystal; Davila, Wilmer Fernando; Mungee, Sudhir

    2016-01-01

    Metastatic cardiac tumors are more common than the primary cardiac tumors. Cervical cancer metastasizing outside of the pelvis is commonly spread to the lungs, liver, bones and lymph nodes than to the heart. Right-sided metastasis to the heart is more common than to the left side. Intramural spread is more common than intracavitary growth of metastatic cardiac tumors leading to delayed clinical presentation. Intracavitary mass can be confused with intracavitary thrombus which can be seen in the setting of pulmonary embolism. Transthoracic echocardiography plays a major role in the decision making and management of pulmonary embolism, and this modality can also be used to diagnose cardiac masses. Other modalities like TEE, cardiac CT, cardiac MRI and PET-CT scan have further utility in delineating these masses. This may help to plan appropriate management of the right ventricular mass particularly in cases where the patient history and CT pulmonary angiography results favor the diagnosis of pulmonary embolism. We present the case of a 49-year-old woman with a history of supracervical hysterectomy and salpingo-oophorectomy on oral estrogen therapy who was admitted with complaints of pleuritic chest pain and respiratory insufficiency after a long flight. Initial work-up showed sub-segmental pulmonary embolus in the right posterior lower lobe pulmonary artery, and the patient was managed on intravenous heparin. Lack of appropriate response to standard therapy led to further evaluation. Multimodality imaging and biopsies revealed a large right intracavitary ventricular metastatic squamous cell tumor, with the cervix as the primary source. PMID:27406457

  5. Left Ventricular Diastolic Dysfunction in Peritoneal Dialysis

    PubMed Central

    Wu, Cho-Kai; Lee, Jen-Kuang; Wu, Yi-Fan; Tsai, Chia-Ti; Chiang, Fu-Tien; Hwang, Juey-Jen; Lin, Jiunn-Lee; Hung, Kuan-Yu; Huang, Jenq-Wen; Lin, Jou-Wei

    2015-01-01

    Abstract Left ventricular diastolic dysfunction (LVDD) is common among patients undergoing peritoneal dialysis (PD). We examined the relationship between LVDD, major adverse cardiovascular events (MACE), and mortality in PD patients. A total of 149 patients undergoing PD with preserved left ventricular systolic function were included and followed for 3.5 years. LVDD was diagnosed (according to the European Society of Cardiology guidelines) by conventional and tissue Doppler echocardiography. Serum high-sensitivity C-reactive protein (hsCRP) was measured. The location and volume of adipose tissue were assessed by computed tomography (CT) at the level of the fourth lumbar vertebra. Subjects with LVDD had higher levels of hsCRP, and more visceral and peritoneal fat than controls. The relationship between adjusted visceral adipose tissue and LVDD became nonsignificant when hsCRP and baseline demographic data were introduced into the logistic regression model (odds ratio = 1.52, P = 0.07). Subsequent hierarchical multivariate Cox regression analysis showed that LVDD was one of the most powerful determinants of MACE and mortality after adjusting for all confounding factors (hazard ratio [HR]: 1.71, 95% confidence interval [CI]: 1.43–3.51, P = 0.02 and HR: 2.25, 95% CI: 1.45–2.91, P = 0.04, respectively). Systemic inflammation (hsCRP) was also significantly associated with MACE and mortality (HR: 2.03, P = 0.03 and HR: 2.16, P = 0.04, respectively). LVDD is associated with systemic inflammation and increased visceral fat in patients undergoing PD. LVDD is also a sensitive, independent indicator of future MACE and mortality in PD patients. PMID:25997054

  6. Safety Testing of Left Ventricular Vent Valves.

    PubMed

    Gavin, Caroline; Coblentz, John; Acsell, Jeffrey R; Shackelford, Anthony G; Sistino, Joseph J

    2015-03-01

    Vent vacuum relief valves (VRVs) are used to limit the negative pressure at the ventricular vent catheter tip as well as prevent reversal of blood flow and prevention of air embolism. The purpose of this study was to evaluate the performance of three commercially available ventricular vent valves. The negative pressure at which the vent valve opened was measured at the valve inlet using high-fidelity pressure transducers. Also, the flow rate at which air entrainment occurred due to valve opening was recorded. Using a 51.5 cm column of saline, the resistance for each valve was calculated. The mean ± SD opening negative pressures were -231.3 ± 35.2 mmHg for the Quest Medical valve, -219.8 mmHg ± 17.2 for the Sorin valve, and -329.6 · 38.0 mmHg for the Terumo valve. The red Quest Medical valve opened at a lower flow (1.44 ± .03 L/min) than the dark blue Sorin valve (2.93 ± .01 L/min) and light blue LH130 Terumo valve (2.36 ± .02 L/min). The Sorin valve had the least resistance of 34.1 dyn-s/cm, followed by the Terumo LH130 valve resistance of 58.1 dyn·s/cm5, and the Quest Medical VRV-II valve with a resistance of 66.5 dyn·s/cm. We found that the valves are significantly different in the negative pressure generated. Understanding the limitations of these devices is important to reduce the occurrence of adverse events associated with venting and to select the best device for a specific clinical application.

  7. LEFT VENTRICULAR HYPERTROPHY AFTER HYPERTENSIVE PREGNANCY DISORDERS

    PubMed Central

    Scantlebury, Dawn C.; Kane, Garvan C.; Wiste, Heather J.; Bailey, Kent R.; Turner, Stephen T.; Arnett, Donna K.; Devereux, Richard B.; Mosley, Thomas H.; Hunt, Steven C.; Weder, Alan B.; Rodriguez, Beatriz; Boerwinkle, Eric; Weissgerber, Tracey L.; Garovic, Vesna D.

    2015-01-01

    Objective Cardiac changes of hypertensive pregnancy include left ventricular hypertrophy (LVH) and diastolic dysfunction. These are thought to regress postpartum. We hypothesized that women with a history of hypertensive pregnancy would have altered left ventricular (LV) geometry and function when compared to women with only normotensive pregnancies. Methods In this cohort study, we analyzed echocardiograms of 2637 women who participated in the Family Blood Pressure Program (FBPP). We compared LV mass and function in women with hypertensive pregnancy compared to those with normotensive pregnancies. Results Women were evaluated at a mean age of 56 years: 427 (16%) had at least one hypertensive pregnancy; 2210 (84%) had normotensive pregnancies. Compared to women with normotensive pregnancies, women with hypertensive pregnancy had a greater risk of LVH (OR: 1.42, 95% CI 1.01-1.99, p=0.05), after adjusting for age, race, research network of the FBPP, education, parity, BMI, hypertension and diabetes. When duration of hypertension was taken into account, this relationship was no longer significant (OR: 1.19, CI 0.08-1.78 p=0.38). Women with hypertensive pregnancies also had greater left atrial size and lower mitral E/A ratio after adjusting for demographic variables. The prevalence of systolic dysfunction was similar between the groups. Conclusions A history of hypertensive pregnancy is associated with LVH after adjusting for risk factors; this might be explained by longer duration of hypertension. This finding supports current guidelines recommending surveillance of women following a hypertensive pregnancy, and sets the stage for longitudinal echocardiographic studies to further elucidate progression of LV geometry and function after pregnancy. PMID:26243788

  8. Left and right ventricular diastolic function in hemodialysis patients.

    PubMed

    Rudhani, Ibrahim Destan; Bajraktari, Gani; Kryziu, Emrush; Zylfiu, Bejtush; Sadiku, Shemsedin; Elezi, Ymer; Rexhepaj, Nehat; Vitia, Arber; Emini, Merita; Abazi, Murat; Berbatovci-Ukimeraj, M; Kryeziu, Kaltrina; Hsanagjekaj, Venera; Korca, Hajrije; Ukimeri, Aferdita

    2010-11-01

    The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD) and the correlation of this function with the duration of HD. The study included 42 patients (22 females and 20 males) with chronic renal failure (CRF), treated with HD, and 40 healthy subjects (24 females and 16 males) with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects underwent detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the interventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E), acceleration time of E wave (AT-E), tricuspid E and A waves (E tr and A tr ) and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.

  9. Percutaneous Ventricular Assist Devices: New Deus Ex Machina?

    PubMed Central

    Arroyo, Diego; Cook, Stéphane

    2011-01-01

    The development of ventricular assist devices has broadened the means with which one can treat acute heart failure. Percutaneous ventricular assist devices (pVAD) have risen from recent technological advances. They are smaller, easier, and faster to implant, all important qualities in the setting of acute heart failure. The present paper briefly describes the functioning and assets of the most common devices used today. It gives an overview of the current evidence and indications for left ventricular assist device use in cardiogenic shock and high-risk percutaneous coronary intervention. Finally, extracorporeal life support devices are dealt with in the setting of hemodynamic support. PMID:22091361

  10. Right ventricular outflow tract tachycardia worsened during pregnancy.

    PubMed

    Kambiré, Yibar; Konaté, Lassina; Millogo, Georges Rosario Christian; Sib, Elodie; Amoussou, Myriam; Nebié, Lucie Valérie Adélaïde; Niakara, Ali

    2015-01-01

    We report the case of a 35 years old woman without underlying heart disease who was diagnosed with a right ventricular outflow tract tachycardia worsened during pregnancy. The diagnosis of ventricular tachycardia was made early in her pregnancy course but the patient had symptoms three months earlier. Her disease course was marked by rhythmic storms during the second trimester of pregnancy that led to three hospitalizations accounting for about two weeks in total. The combination of nadolol 80 mg and flecainide tablets 150 mg improved her rhythmic storms. Radiofrequency allowed a radical cure of this ventricular tachycardia. The patient is now asymptomatic 27 months after radiofrequency treatment. PMID:26090018

  11. Hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus.

    PubMed

    Van Treeck, Benjamin J; Masoud, Amgad G

    2014-01-01

    Clinical hypothyroidism is the most common hormone deficiency in the United States and is found in 0.3% of the U.S. population. It is associated with characteristic symptoms that can be readily identified by a careful history and physical examination. Hypothyroidism affects many bodily systems; in particular the cardiovascular system is impacted via multiple mechanisms.3 Occasionally hypothyroidism leads to transient left ventricular systolic dysfunction, termed hypothyroid cardiomyopathy. A rare sequela of this condition is a left ventricular thrombus, which has been described in two case reports thus far. Here we report a third case of reversible hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus. PMID:25438369

  12. [Coronary effects of left ventricular hypertrophy associated with hypertension].

    PubMed

    Trimarco, B; de Luca, N; Ricciardelli, B; Rosiello, G; Lembo, G; Rendina, V; Raponi, M; Marchegiano, R; Volpe, M

    1990-12-01

    Left ventricular hypertrophy secondary to hypertension has been associated with a reduction of maximum coronary flow per unit mass as shown by the increase in the minimal threshold of coronary vascular resistance per gramme. This phenomenon has usually been attributed to an increase in muscle mass with absent or inadequate vascular compensation. However, chronic hypertension may induce a function reduction in coronary flow. In particular, it has been recently shown that coronary vascular resistances are influenced by a cardio-cardiac reflex involving the baroreceptor response. Left ventricular hypertrophy could alter the function of the ventricular receptors and favourise myocardial ischemia by preventing the adaptation of coronary flow to myocardial metabolic demands.

  13. Arrhythmogenic right ventricular cardiomyopathy/dysplasia: an updated imaging approach.

    PubMed

    Zimmerman, Stefan L

    2015-02-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a rare inherited cardiomyopathy characterized by fibrofatty replacement of the right ventricular myocardium and risk of sudden death from ventricular tachyarrhythmias. Cardiac magnetic resonance (MR) imaging plays an important role in the diagnostic evaluation of patients and family members suspected of having ARVC/D. This article discusses the epidemiology and pathophysiology of ARVC/D, reviews typical MR imaging findings and diagnostic criteria, and summarizes potential pitfalls in the MR imaging evaluation of patients suspected of having ARVC/D.

  14. A Case of Cough-induced Ventricular Tachycardia in a Patient with a Left Ventricular Assist Device.

    PubMed

    Ruckdeschel, Emily Sue; Wolfel, Eugene; Nguyen, Duy Thai

    2016-03-01

    In this case, the patient's ventricular tachycardia (VT) was specifically induced by coughing, which has not previously been described. Decreasing the rotational speed of the left ventricular assist device (LVAD) and increasing preload by stopping the patient's nitrates and reducing diuretic dose allowed improved filling of the left ventricle (LV) and increased LV volumes. When coughing recurred, the effects on the LV cavity were less pronounced and thus VT was reduced. Although ventricular arrhythmias are common after LVAD placement, this is a unique case in which VT was caused by coughing, which is ordinarily not considered arrhythmogenic. PMID:26920187

  15. How best to assess right ventricular function by echocardiography*

    PubMed Central

    DiLorenzo, Michael P.; Bhatt, Shivani M.; Mercer-Rosa, Laura

    2016-01-01

    Right ventricular function is a crucial determinant of long-term outcomes of children with heart disease. Quantification of right ventricular systolic and diastolic performance by echocardiography is of paramount importance, given the prevalence of children with heart disease, particularly those with involvement of the right heart, such as single or systemic right ventricles, tetralogy of Fallot, and pulmonary arterial hypertension. Identification of poor right ventricular performance can provide an opportunity to intervene. In this review, we will go through the different systolic and diastolic indices, as well as their application in practice. Quantification of right ventricular function is possible and should be routinely performed using a combination of different measures, taking into account each disease state. Quantification is extremely useful for individual patient follow-up. Laboratories should continue to strive to optimise reproducibility through quality improvement and quality assurance efforts in addition to investing in technology and training for new, promising techniques, such as three-dimensional echocardiography. PMID:26675593

  16. Ablation of frequent premature ventricular complex in an athlete.

    PubMed

    Grazioli, G; Fernández-Armenta, J; Prat, S; Berruezo, A; Brugada, J; Sitges, M

    2015-12-01

    Premature ventricular complex are common findings in the exam of many athletes. There is no extensive scientific evidence in the management of this situation particularly when associated with borderline contractile function of the left ventricle. In this case report, we present a 35-year-old asymptomatic healthy athlete with high incidence (over 10,000 beats in 24 h) of premature ventricular complex and left ventricular dilatation with dysfunction, which persisted after a resting period of 6 months without training. We performed radiofrequency ablation of the premature ventricular complex focus. After 1-year follow-up, he was asymptomatic without arrhythmia and the left ventricle normalized its size and function as shown by echocardiogram and cardiac magnetic resonance.

  17. Eisenmenger ventricular septal defect in a Humboldt penguin (Spheniscus humboldti).

    PubMed

    Laughlin, D S; Ialeggio, D M; Trupkiewicz, J G; Sleeper, M M

    2016-09-01

    The Eisenmenger ventricular septal defect is an uncommon type of ventricular septal defect characterised in humans by a traditionally perimembranous ventricular septal defect, anterior deviation (cranioventral deviation in small animal patients) of the muscular outlet septum causing malalignment relative to the remainder of the muscular septum, and overriding of the aortic valve. This anomaly is reported infrequently in human patients and was identified in a 45-day-old Humboldt Penguin, Spheniscus humboldti, with signs of poor growth and a cardiac murmur. This case report describes the findings in this penguin and summarises the anatomy and classification of this cardiac anomaly. To the authors' knowledge this is the first report of an Eisenmenger ventricular septal defect in a veterinary patient.

  18. Idiopathic Paroxysmal Ventricular Tachycardia in Infants and Children

    ERIC Educational Resources Information Center

    Hernandez, Antonio; And Others

    1975-01-01

    Laboratory tests including blood count serum electrolyte measures, and electroencephalograms were performed on seven children ages 1 day to 18 years with recurrent attacks of rapid heart action known as idiopathic paroxysmal ventricular tachycardia. (CL)

  19. How best to assess right ventricular function by echocardiography.

    PubMed

    DiLorenzo, Michael P; Bhatt, Shivani M; Mercer-Rosa, Laura

    2015-12-01

    Right ventricular function is a crucial determinant of long-term outcomes of children with heart disease. Quantification of right ventricular systolic and diastolic performance by echocardiography is of paramount importance, given the prevalence of children with heart disease, particularly those with involvement of the right heart, such as single or systemic right ventricles, tetralogy of Fallot, and pulmonary arterial hypertension. Identification of poor right ventricular performance can provide an opportunity to intervene. In this review, we will go through the different systolic and diastolic indices, as well as their application in practice. Quantification of right ventricular function is possible and should be routinely performed using a combination of different measures, taking into account each disease state. Quantification is extremely useful for individual patient follow-up. Laboratories should continue to strive to optimise reproducibility through quality improvement and quality assurance efforts in addition to investing in technology and training for new, promising techniques, such as three-dimensional echocardiography.

  20. Eisenmenger ventricular septal defect in a Humboldt penguin (Spheniscus humboldti).

    PubMed

    Laughlin, D S; Ialeggio, D M; Trupkiewicz, J G; Sleeper, M M

    2016-09-01

    The Eisenmenger ventricular septal defect is an uncommon type of ventricular septal defect characterised in humans by a traditionally perimembranous ventricular septal defect, anterior deviation (cranioventral deviation in small animal patients) of the muscular outlet septum causing malalignment relative to the remainder of the muscular septum, and overriding of the aortic valve. This anomaly is reported infrequently in human patients and was identified in a 45-day-old Humboldt Penguin, Spheniscus humboldti, with signs of poor growth and a cardiac murmur. This case report describes the findings in this penguin and summarises the anatomy and classification of this cardiac anomaly. To the authors' knowledge this is the first report of an Eisenmenger ventricular septal defect in a veterinary patient. PMID:27286906

  1. Left ventricular assist devices—current state and perspectives

    PubMed Central

    Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-01-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature. PMID:27621895

  2. Canine left ventricular mass estimation by two-dimensional echocardiography.

    PubMed

    Schiller, N B; Skiôldebrand, C G; Schiller, E J; Mavroudis, C C; Silverman, N H; Rahimtoola, S H; Lipton, M J

    1983-07-01

    This study was designed to develop a two-dimensional echocardiographic method of measuring the mass of the left ventricle. The general formula for an ellipse was used to derive an algorithm that described the shell volume of concentric truncated ellipsoids. In 10 canine left ventricular two-dimensional echocardiograms, this algorithm accurately predicted postmortem left ventricular mass (r = .98, SEE +/- 6 g) and was independent of cardiac cycle phase (systole vs diastole, r = .92). PMID:6851047

  3. Left ventricular assist devices-current state and perspectives.

    PubMed

    Prinzing, Anatol; Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-08-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature. PMID:27621895

  4. Left ventricular assist devices—current state and perspectives

    PubMed Central

    Herold, Ulf; Berkefeld, Anna; Krane, Markus; Lange, Rüdiger; Voss, Bernhard

    2016-01-01

    Mechanical circulatory support devices have become an important treatment tool for severe acute and chronic heart failure, since heart transplantation cannot meet the demands because of a lack of available donor organs. Since implantation of the first ventricular assist device a constant development of the suitability of these devices has been made. This review will introduce different generations of left ventricular assist devices (LVAD) and elaborate on clinical indications, risk stratification and current literature.

  5. Ultrasound stylet for non-image-guided ventricular catheterization.

    PubMed

    Coulson, Nathaniel K; Chiarelli, Peter A; Su, David K; Chang, Jason J; MacConaghy, Brian; Murthy, Revathi; Toms, Peter; Robb, Terrence L; Ellenbogen, Richard G; Browd, Samuel R; Mourad, Pierre D

    2015-10-01

    OBJECT Urgent ventriculostomy placement can be a lifesaving procedure in the setting of hydrocephalus or elevated intracranial pressure. While external ventricular drain (EVD) insertion is common, there remains a high rate of suboptimal drain placement. Here, the authors seek to demonstrate the feasibility of an ultrasound-based guidance system that can be inserted into an existing EVD catheter to provide a linear ultrasound trace that guides the user toward the ventricle. METHODS The ultrasound stylet was constructed as a thin metal tube, with dimensions equivalent to standard catheter stylets, bearing a single-element, ceramic ultrasound transducer at the tip. Ultrasound backscatter signals from the porcine ventricle were processed by custom electronics to offer real-time information about ventricular location relative to the catheter. Data collected from the prototype device were compared with reference measurements obtained using standard clinical ultrasound imaging. RESULTS A study of porcine ventricular catheterization using the experimental device yielded a high rate of successful catheter placement after a single pass (10 of 12 trials), despite the small size of pig ventricles and the lack of prior instruction on porcine ventricular architecture. A characteristic double-peak signal was identified, which originated from ultrasound reflections off of the near and far ventricular walls. Ventricular dimensions, as obtained from the width between peaks, were in agreement with standard ultrasound reference measurements (p < 0.05). Furthermore, linear ultrasound backscatter data permitted in situ measurement of the stylet distance to the ventricular wall (p < 0.05), which assisted in catheter guidance. CONCLUSIONS The authors have demonstrated the ability of the prototype ultrasound stylet to guide ventricular access in the porcine brain. The alternative design of the device makes it potentially easy to integrate into the standard workflow for bedside EVD

  6. Sequential radionuclide imaging during paracorporeal left ventricular support.

    PubMed

    Sweet, S E; Sussman, H A; Ryan, T J; Bernhard, W F; Berger, R L

    1980-09-01

    A paracorporeal left ventricular to ascending aorta assist device (LVAD) was utilized in four patients with refractory cardiogenic shock following cardiac surgery. Hemodynamic stabilization was achieved in all four patients, two of whom were subsequently discharged from the hospital and continue to do well one year later. A technique is described for obtaining radionuclide ejection fractions (EFs) during temporary LVAD interruption. The EFs appeared to be predictive of eventual unassisted ventricular function and possibly of patient survival.

  7. Unique properties of the ATP-sensitive K⁺ channel in the mouse ventricular cardiac conduction system.

    PubMed

    Bao, Li; Kefaloyianni, Eirini; Lader, Joshua; Hong, Miyoun; Morley, Gregory; Fishman, Glenn I; Sobie, Eric A; Coetzee, William A

    2011-12-01

    Background- The specialized cardiac conduction system (CCS) expresses a unique complement of ion channels that confer a specific electrophysiological profile. ATP-sensitive potassium (K(ATP)) channels in these myocytes have not been systemically investigated. Methods and Results- We recorded K(ATP) channels in isolated CCS myocytes using Cntn2-EGFP reporter mice. The CCS K(ATP) channels were less sensitive to inhibitory cytosolic ATP compared with ventricular channels and more strongly activated by MgADP. They also had a smaller slope conductance. The 2 types of channels had similar intraburst open and closed times, but the CCS K(ATP) channel had a prolonged interburst closed time. CCS K(ATP) channels were strongly activated by diazoxide and less by levcromakalim, whereas the ventricular K(ATP) channel had a reverse pharmacological profile. CCS myocytes express elevated levels of Kir6.1 but reduced Kir6.2 and SUR2A mRNA compared with ventricular myocytes (SUR1 expression was negligible). SUR2B mRNA expression was higher in CCS myocytes relative to SUR2A. Canine Purkinje fibers expressed higher levels of Kir6.1 and SUR2B protein relative to the ventricle. Numeric simulation predicts a high sensitivity of the Purkinje action potential to changes in ATP:ADP ratio. Cardiac conduction time was prolonged by low-flow ischemia in isolated, perfused mouse hearts, which was prevented by glibenclamide. Conclusions- These data imply a differential electrophysiological response (and possible contribution to arrhythmias) of the ventricular CCS to K(ATP) channel opening during periods of ischemia.

  8. Ventricular repolarization in a rat model of global heart failure.

    PubMed

    Krandycheva, Valeria; Kharin, Sergey; Strelkova, Marina; Shumikhin, Konstantin; Sobolev, Aleksey; Shmakov, Dmitry

    2013-07-01

    Isoproterenol in high doses induces infarction-like myocardial damage and structural and functional remodelling of the ventricular myocardium. The purpose of the present study was to investigate ventricular repolarization in a rat model of isoproterenol-induced heart failure. Isoproterenol was administered twice to female Wistar rats (170 mg/kg, s.c., 24 h apart). Four weeks after the injections, cardiac output was measured and unipolar epicardial ventricular electrograms were recorded in situ. Activation-recovery intervals were calculated to assess repolarization. Histological examination of the heart ventricles was also performed. Heart failure in rats treated with isoproterenol was indicated by myocardial histopathological damage and reduced cardiac output. In rats with heart failure, the regional differences in activation-recovery interval prolongation over the ventricular epicardium resulted in increasing heterogeneity in the activation-recovery interval distribution and increasing repolarization heterogeneity of the ventricular subepicardium. Myocardial damage and haemodynamic changes in heart failure induced by isoproterenol were accompanied by significant changes in ventricular repolarization, which were not associated with myocardial hypertrophy.

  9. Fetal Right Ventricular Diverticulum Detected by Prenatal Ultrasound Screening

    PubMed Central

    Hayashi, Kaori; Tsuji, Shunichiro; Ono, Tetsuo; Ishiko, Akiko; Takahashi, Kentaro; Murakami, Takashi

    2016-01-01

    Prenatal ultrasound screening has allowed for the detection of in utero cardiac abnormalities. Specifically, distinction is possible between ventricular diverticula and aneurysms, which is important because each condition has a different clinical outcome. We report the case of a 35-year-old, gravida 1, para 1 woman, with no significant past medical history, who underwent routine prenatal ultrasound screening at 32 weeks' gestation. A four-chamber ultrasound of the fetal heart combined with M-mode echocardiography showed abnormal dilatation of the right ventricular chamber measuring 2.2 cm × 1.0 cm but with normal contractility. Delivery was performed at full term by cesarean section, and a right ventricular diverticulum was confirmed by postnatal cardiac computed tomography. The baby developed normally with no cardiac sequelae during followup. This case demonstrates the importance of making a correct diagnosis of ventricular diverticula by prenatal ultrasound when abnormal dilatation of the fetal ventricle is identified during routine screening. Because evaluating the wall contractility by M-mode ultrasound leads to evaluating whether it has the myocardium, we conclude that M-mode echocardiography is effective for the purpose of prenatal cardiac diagnosis and can distinguish between ventricular aneurysms and functioning ventricular diverticula.

  10. A Striking Coronary Artery Pattern in a Grown-Up Congenital Heart Disease Patient

    PubMed Central

    Iacovelli, Fortunato; Pepe, Martino; Contegiacomo, Gaetano; Alberotanza, Vito; Masi, Filippo; Bortone, Alessandro Santo; Favale, Stefano

    2016-01-01

    Left ventricular noncompaction (LVNC) is a myocardial disorder probably due to the arrest of normal embryogenesis of the left ventricle. It could be isolated or associated with other extracardiac and cardiac abnormalities, including coronary artery anomalies. Despite the continuous improvement of imaging resolution quality, this cardiomyopathy still remains frequently misdiagnosed, especially if associated with other heart diseases. We report a case of LVNC association with both malposition of the great arteries and a very original coronary artery pattern. PMID:26881144

  11. A Striking Coronary Artery Pattern in a Grown-Up Congenital Heart Disease Patient.

    PubMed

    Iacovelli, Fortunato; Pepe, Martino; Contegiacomo, Gaetano; Alberotanza, Vito; Masi, Filippo; Bortone, Alessandro Santo; Favale, Stefano

    2016-01-01

    Left ventricular noncompaction (LVNC) is a myocardial disorder probably due to the arrest of normal embryogenesis of the left ventricle. It could be isolated or associated with other extracardiac and cardiac abnormalities, including coronary artery anomalies. Despite the continuous improvement of imaging resolution quality, this cardiomyopathy still remains frequently misdiagnosed, especially if associated with other heart diseases. We report a case of LVNC association with both malposition of the great arteries and a very original coronary artery pattern. PMID:26881144

  12. Unruptured Sinus of Valsalva Aneurysm with Right Ventricular Outflow Tract Obstruction and Supracristal Ventricular Septal Defect: A Rare Case.

    PubMed

    Sridhar, Ganiga Srinivasaiah; Sadiq, Muhammad Athar; Ahmad, Wan Azman Wan; Supuramaniam, Chitra; Watson, Timothy; Abidin, Imran Zainal; Chee, Kok Han

    2015-10-01

    Unruptured right sinus of Valsalva aneurysm that causes severe obstruction of the right ventricular outflow tract is extremely rare. We describe the case of a 47-year-old woman who presented with exertional dyspnea. Upon investigation, we discovered an unruptured right sinus of Valsalva aneurysm with associated right ventricular outflow tract obstruction and a supracristal ventricular septal defect. To our knowledge, only 2 such cases have previously been reported in the medical literature. Although treatment of unruptured sinus of Valsalva aneurysm remains debatable, surgery should be considered for extremely large aneurysms or for progressive enlargement of the aneurysm on serial evaluation. Surgery was undertaken in our patient because there was clear evidence of right ventricular outflow tract obstruction, right-sided heart dilation, and associated exertional dyspnea.

  13. Use of right ventricular support with a centrifugal pump in post-valve surgery right ventricular failure: a case series.

    PubMed

    Moulodi, Abdol Rasoul; Sheibat Zadeh, Gholam Reza; Sabzi, Feridoun

    2014-01-12

    The optimal treatment method for right ventricular failure after valve surgery complicated by a low cardiac output has not been determined, although several case reports have been published on patients with ventricular failure and arrhythmia who were bridged to cardiac transplantation using biventricular or left ventricular assist devices. This case series illustrates successful circulatory support of 4 patients with prolonged low cardiac outputs and right ventricular failure and arrhythmias after valvular heart surgery with or without severe pulmonary hypertension. In-hospital death occurred in one patient and 3 patients were discharged from the hospital with good general condition. At two years' follow-up, 2 patients were in functional class one but another patient underwent laparotomy for multiple splenic abscesses and died from multiple organ failure.

  14. Left ventricular mechanics and arterial-ventricular coupling following high-intensity interval exercise.

    PubMed

    Cote, Anita T; Bredin, Shannon S D; Phillips, Aaron A; Koehle, Michael S; Glier, Melissa B; Devlin, Angela M; Warburton, Darren E R

    2013-12-01

    High-intensity exercise induces marked physiological stress affecting the secretion of catecholamines. Sustained elevations in catecholamines are thought to desensitize cardiac beta receptors and may be a possible mechanism in impaired cardiac function following strenuous exercise. In addition, attenuated arterial-ventricular coupling may identify vascular mechanisms in connection with postexercise attenuations in ventricular function. Thirty-nine normally active (NA) and endurance-trained (ET) men and women completed an echocardiographic evaluation of left ventricular function before and after an acute bout of high-intensity interval exercise (15 bouts of 1:2 min work:recovery cycling: 100% peak power output and 50 W, respectively). Following exercise, time to peak twist and peak untwisting velocity were delayed (P < 0.01) but did not differ by sex or training status. Interactions for sex and condition (rest vs. exercise) were found for longitudinal diastolic strain rate (men, 1.46 ± 0.19 to 1.28 ± 0.23 s(-1) vs. women, 1.62 ± 0.25 to 1.63 ± 0.26 s(-1); P = 0.01) and arterial elastance (men 2.20 ± 0.65 to 3.24 ± 1.02 mmHg · ml(-1) · m(-2) vs. women 2.51 ± 0.61 to 2.93 ± 0.68 mmHg · ml(-1) · m(-2); P = 0.04). No cardiac variables were found associated with catecholamine levels. The change in twist mechanics was associated with baseline aortic pulse-wave velocity (r(2) = 0.27, P = 0.001). We conclude that males display greater reductions in contractility in response to high-intensity interval exercise, independent of catecholamine concentrations. Furthermore, a novel association of arterial stiffness and twist mechanics following high-intensity acute exercise illustrates the influence of vascular integrity on cardiac mechanics.

  15. [The process of ventricular remodeling after acute myocardial infarct associated with left ventricular aneurysm and ventricular septum rupture treated with radical surgery].

    PubMed

    Hůla, J

    1997-01-01

    Even after a successful operation of mechanical complications on account of acute myocardial infarction gradually developing adverse remodelling of the left ventricle has to be envisaged. In a six-year clinical study by means of echocardiography the authors followed up systematically some cardiac dimensions and volumes and functional systolic and diastolic left ventricular parameters. The changes pertained in particular to the endsystolic and enddiastolic volume, the ejection fraction, the peak maximum rate, early and late diastolic filling and their ratio as well as to indirect values of the mean pressure in the pulmonary artery. These changes, which at first indicated impaired relaxation, are caused subsequently by increasing stiffness of the left ventricle. With regard to the large number of complicated pathophysiological phenomena pertaining to active relaxation and passive elastic properties of the left ventricle during ventricular diastole, different Doppler parameters must be evaluated very carefully, individually and with regard to the clinical condition. Attention is drawn to the importance of complicating mitral regurgitations and an increased pressure in the left atrium and lesser circulation after aneurysmectomy of the left ventricle. Mitral regurgitation has an impact on the process of left ventricular filling investigated by means of diastolic Doppler functions. Despite limitations of echocardiographic methods within the framework of assessment of diastolic left ventricular functions after myocardial infarction echocardiography remains the main means for evaluating left ventricular function by a non-invasive route and its position in this respect is irreplaceable. Further experimental work is needed for better understanding, use and more intelligent interpretation of non-invasive parameters of left ventricular function also in these complicated conditions after surgery of mechanical complications resulting from myocardial infarction. PMID:9221569

  16. Ventricular volume measured from sestamibi gated tomograms

    SciTech Connect

    Nichols, K.; DePuey, E.G.; Salensky, H. |

    1994-05-01

    Since left ventricular (LV) end-diastolic volume (EDV) and end-systolic volume (ESV) are valuable prognostic indicators, deriving accurate LV volumes could enhance the prognostic utility of Tc-99m sestamibi myocardial perfusion SPECT. We examined two methods of obtaining volumes adjunctive to sestamibi injections. A previously reported method of computing volumes from gated first pass (FP) images by combining maximum and total counts with IV maximum depth information from an orthogonal view was tested by imaging the LV chamber of a thoracic/cardiac phantom in RAO-30{degrees} and LAO-60{degrees} projections. Computed volume agreed with known volume to within 4.9%. In a separate experiment, tomograms of the simulated myocardium of the phantom were acquired which were reoriented into vertical and horizontal long-axis slices on which an observer drew inner LV outlines, and from which volume was computed using a scatter-corrected Simpson`s rule method. Computed phantom volume agreed with known simulated LV volume to within 3.5%. To evaluate these volume methods for patient data, we analyzed LV ED and ES images of 39 patients acquired in simultaneous biplane RAO-30{degrees} and LAO-60{degrees} projections during FP bolus transit of 840 MBq Tc-99m sestamibi. One hour later, 64 projections were acquired in 64{sup 2} matrices for 20 seconds each, gated at 8 frames per R-R interval.

  17. CFD Modeling of Ventricular Assist Device

    NASA Astrophysics Data System (ADS)

    Wood, Houston; Allaire, Paul; McDaniel, James; Landrot, Nicolas; Day, Steven

    2000-11-01

    The HeartQuest blood pump is a centrifugal pump in which the rotor is suspended by magnetic bearings. The pump is being designed for use as an implantable Ventricular Assist Device. In previous computational modeling of the pump, the blood flow in three separate regions has been analyzed: the impeller, the front clearance region and the back clearance region. In this approach, the models are axially symmetric, and the calculations are simplified. However, the real flow is 3-dimensional because of the exit volute. In order to validate computational fluid dynamics modeling of the blood pump, a complete computational model has been realized. The computational model includes an impeller, a front clearance gap, a back clearance gap, and an exit volute. The full Navier-Stokes equations are solved inside the pump, and a k-e model is used to model the turbulence. The software used is the commercially available program TASCFLOW from the company AEA. In this paper, numerical predictions will be explained and compared with experimental measurements of the flow field obtained by laser particle imaging velocimetry.

  18. Endocarditis in left ventricular assist device

    PubMed Central

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-01-01

    Summary Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement. PMID:27672540

  19. Ventricular fibrillation time constant for swine.

    PubMed

    Wu, Jiun-Yan; Nimunkar, Amit J; Sun, Hongyu; O'Rourke, Ann; Huebner, Shane; Will, James A; Webster, John G

    2008-10-01

    The strength-duration curve for cardiac excitation can be modeled by a parallel resistor-capacitor circuit that has a time constant. Experiments on six pigs were performed by delivering current from the X26 Taser dart at a distance from the heart to cause ventricular fibrillation (VF). The X26 Taser is an electromuscular incapacitation device (EMD), which generates about 50 kV and delivers a pulse train of about 15-19 pulses s(-1) with a pulse duration of about 150 micros and peak current about 2 A. Similarly a continuous 60 Hz alternating current of the amplitude required to cause VF was delivered from the same distance. The average current and duration of the current pulse were estimated in both sets of experiments. The strength-duration equation was solved to yield an average time constant of 2.87 ms +/- 1.90 (SD). Results obtained may help in the development of safety standards for future electromuscular incapacitation devices (EMDs) without requiring additional animal tests.

  20. Arrhythmogenic Right Ventricular Dysplasia in Neuromuscular Disorders

    PubMed Central

    Finsterer, Josef; Stöllberger, Claudia

    2016-01-01

    OBJECTIVES Arrhythmogenic right ventricular dysplasia (ARVD) is a rare, genetic disorder predominantly affecting the right ventricle. There is increasing evidence that in some cases, ARVD is due to mutations in genes, which have also been implicated in primary myopathies. This review gives an overview about myopathy-associated ARVD and how these patients can be managed. METHODS A literature review was done using appropriate search terms. RESULTS The myopathy, which is most frequently associated with ARVD, is the myofibrillar myopathy due to desmin mutations. Only in a single patient, ARVD was described in myotonic dystrophy type 1. However, there are a number of genes causing either myopathy or ARVD. These genes include lamin A/C, ZASP/cypher, transmembrane protein-43, titin, and the ryanodine receptor-2 gene. Diagnosis and treatment are identical for myopathy-associated ARVD and nonmyopathy-associated ARVD. CONCLUSIONS Patients with primary myopathy due to mutations in the desmin, dystrophia myotonica protein kinase, lamin A/C, ZASP/cypher, transmembrane protein-43, titin, or the ryanodine receptor-2 gene should be screened for ARVD. Patients carrying a pathogenic variant in any of these genes should undergo annual cardiological investigations for cardiac function and arrhythmias. PMID:27790050

  1. [Takotsubo syndrome. Transient left ventricular dyskinesia].

    PubMed

    Pérez Pérez, F M; Sánchez Salado, J

    2014-03-01

    The Takotsubo syndrome, also called transient apical dyskinesia syndrome, was first described in Japan in the 1990s. It is a rare entity found in almost 1% of all patients with suspicion of acute coronary syndrome. It usually affects postmenopausal women with a few cardiovascular risk factors. It is characterized by angina-type chest pain, electrocardiographic changes, elevation of the enzymes of myocardial injury, absence of coronary obstruction on angiography, and a characteristic left ventricular anteroapical dyskinesia, which returns to normal within a few days. Severe emotional stress is the most common trigger for this syndrome. The aetiopathogenesis of this syndrome remains to be defined. This syndrome has been considered a clinical condition since 2001, when a series of 88 cases was published. It is a disease with a partially known mechanism, characterised by the morphology adopted by the left ventricle secondary to hypokinesis or dyskinesia of the apical segments, and hypercontractility of basal segments. Unlike acute coronary syndrome, patients with left ventricle dysfunction do not have atherothrombotic disease in the coronary arteries. In addition, the alterations described are reversible. Some clinical diagnostic criteria have been proposed, although they are still controversial, as well as in the complementary examinations required for diagnosis.

  2. Loperamide Induced Life Threatening Ventricular Arrhythmia

    PubMed Central

    Bodar, Vijaykumar; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community. PMID:27547470

  3. Loperamide Induced Life Threatening Ventricular Arrhythmia.

    PubMed

    Upadhyay, Ankit; Bodar, Vijaykumar; Malekzadegan, Mohammad; Singh, Sharanjit; Frumkin, William; Mangla, Aditya; Doshi, Kaushik

    2016-01-01

    Loperamide is over-the-counter antidiarrheal agent acting on peripherally located μ opioid receptors. It is gaining popularity among drug abusers as opioid substitute. We report a case of a 46-year-old male that was presented after cardiac arrest. After ruling out ischemia, cardiomyopathy, pulmonary embolism, central nervous system pathology, sepsis, and other drug toxicity, we found out that patient was using around 100 mg of Loperamide to control his chronic diarrhea presumably because of irritable bowel syndrome for last five years and consumed up to 200 mg of Loperamide daily for last two days before the cardiac arrest. We hypothesize that the patient's QTc prolongation and subsequent cardiac arrest are due to Loperamide toxicity. Patient experienced gradual resolution of tachyarrhythmia and gradual decrease in QTc interval during hospitalization which supports the evidence of causal relationship between Loperamide overdose and potentially fatal arrhythmias. It also provided the clue that patient may have congenital long QT syndrome which was unmasked by Loperamide causing ventricular arrhythmias. This case adds one more pearl in the literature to support that Loperamide overdose related cardiac toxicity does exist and it raises concerns over Loperamide abuse in the community. PMID:27547470

  4. Endocarditis in left ventricular assist device.

    PubMed

    Thyagarajan, Braghadheeswar; Kumar, Monisha Priyadarshini; Sikachi, Rutuja R; Agrawal, Abhinav

    2016-08-01

    Heart failure is one of the leading causes of death in developed nations. End stage heart failure often requires cardiac transplantation for survival. The left ventricular assist device (LVAD) has been one of the biggest evolvements in heart failure management often serving as bridge to transplant or destination therapy in advanced heart failure. Like any other medical device, LVAD is associated with complications with infections being reported in many patients. Endocarditis developing secondary to the placement of LVAD is not a frequent, serious and difficult to treat condition with high morbidity and mortality. Currently, there are few retrospective studies and case reports reporting the same. In our review, we found the most common cause of endocarditis in LVAD was due to bacteria. Both bacterial and fungal endocarditis were associated with high morbidity and mortality. In this review we will be discussing the risk factors, organisms involved, diagnostic tests, management strategies, complications, and outcomes in patients who developed endocarditis secondary to LVAD placement. PMID:27672540

  5. Pregnancy course and outcomes in women with arrhythmogenic right ventricular cardiomyopathy

    PubMed Central

    Hodes, Anke R; Tichnell, Crystal; te Riele, Anneline S J M; Murray, Brittney; Groeneweg, Judith A; Sawant, Abhishek C; Russell, Stuart D; van Spaendonck-Zwarts, Karin Y; van den Berg, Maarten P; Wilde, Arthur A; Tandri, Harikrishna; Judge, Daniel P; Hauer, Richard N W; Calkins, Hugh; van Tintelen, J Peter; James, Cynthia A

    2016-01-01

    Objectives To characterise pregnancy course and outcomes in women with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). Methods From a combined Johns Hopkins/Dutch ARVD/C registry, we identified 26 women affected with ARVD/C (by 2010 Task Force Criteria) during 39 singleton pregnancies >13 weeks (1–4 per woman). Cardiac symptoms, treatment and episodes of sustained ventricular arrhythmias (VAs) and heart failure (HF) ≥ Class C were characterised. Obstetric outcomes were ascertained. Incidence of VA and HF were compared with rates in the non-pregnant state. Long-term disease course was compared with 117 childbearing-aged female patients with ARVD/C who had not experienced pregnancy with ARVD/C. Results Treatment during pregnancy (n=39) included β blockers (n=16), antiarrhythmics (n=6), diuretics (n=3) and implantable cardioverter defibrillators (ICDs) (n=28). In five pregnancies (13%), a single VA occurred, including two ICD-terminated events. Arrhythmias occurred disproportionately in probands without VA history (p=0.045). HF, managed on an outpatient basis, developed in two pregnancies (5%) in women with pre-existing overt biventricular or isolated right ventricular disease. All infants were live-born without major obstetric complications. Caesarean sections (n=11, 28%) had obstetric indications, except one (HF). β Blocker therapy was associated with lower birth weight (3.1±0.48 kg vs 3.7±0.57 kg; p=0.002). During follow-up children remained healthy (median 3.4 years), and mothers were without cardiac mortality or transplant. Neither VA nor HF incidence was significantly increased during pregnancy. ARVD/C course (mean 6.5±5.6 years) did not differ based on pregnancy history. Conclusions While most pregnancies in patients with ARVD/C were tolerated well, 13% were complicated by VA and 5% by HF. PMID:26719359

  6. Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery

    PubMed Central

    Goldsmith, Yulia; Chan, Jacqueline; Iskandir, Marina; Gulkarov, Iosif; Tortolani, Anthony; Brener, Sorin J.; Sacchi, Terrence J.; Heitner, John F.

    2015-01-01

    Background The significance of right ventricular ejection fraction (RVEF), independent of left ventricular ejection fraction (LVEF), following isolated coronary artery bypass grafting (CABG) and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR), independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery. Methods From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female) were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered <35% and <45%, respectively. Elective primary procedures include CABG (56%) and valve (44%). Thirty-day outcomes were perioperative complications, length of stay, cardiac re-hospitalizations and early mortaility; long-term (> 30 days) outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months. Findings Forty-eight patients had reduced RVEF (mean 25%) and 61 patients had normal RVEF (mean 50%) (p<0.001). Fifty-four patients had reduced LVEF (mean 30%) and 55 patients had normal LVEF (mean 59%) (p<0.001). Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05). Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03). Reduced LVEF did not influence long-term cardiac re-hospitalization. Conclusion Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures. PMID:26197273

  7. Morphology of left ventricular outflow tract structures in patients with subaortic stenosis and a ventricular septal defect.

    PubMed Central

    Kitchiner, D; Jackson, M; Malaiya, N; Walsh, K; Peart, I; Arnold, R; Smith, A

    1994-01-01

    OBJECTIVE--To compare the incidence and prognosis of subaortic stenosis associated with a ventricular septal defect and to define the morphological basis of subaortic stenosis. DESIGN--Presentation and follow up data on 202 patients with subaortic stenosis seen at the Royal Liverpool Children's Hospital between 1 January 1960 and 31 December 1991 were reviewed. Survivors were traced to assess their current clinical state. Necropsy specimens of 291 patients with lesions associated with subaortic stenosis were also examined. RESULTS--In the clinical study; 65 (32.1%) of the 202 patients with subaortic stenosis had a ventricular septal defect (excluding an atrioventricular septal defect). 32 of these patients had a short segment (fibromuscular) subaortic stenosis. 33 had subaortic stenosis produced by deviation of muscular components of the outflow tracts. In 17 patients (51.5%) this was caused by posterior deviation or extension of structures into the left ventricular outflow tract, resulting in obstruction above the ventricular septal defect. In the other 16 patients (48.5%) there was over-riding of the aorta with concordant ventriculoarterial connections, (without compromise to right ventricular outflow) producing subaortic stenosis below the ventricular septal defect. Additional fibrous obstruction occurred in 39% of the patients with deviated structures. The age at presentation was lower (P < 0.01) in patients with deviated structures (median (range) 0.4 (0 to 9.2) months) than in those with short segment obstruction (median (range) 4.2 (0 to 84.9) months). The incidence of aortic arch obstruction was higher (P < 0.002) in patients with deviated structures than in those with short segment obstruction (38%). In the morphological study 35 pathological specimens showed obstructive muscular structures in the left ventricular outflow tract either above or below the ventricular septal defect. 16 had either posterior deviation of the outlet septum or extension of the

  8. Dysplastic conditions of the right ventricular myocardium: Uhl's anomaly vs arrhythmogenic right ventricular dysplasia.

    PubMed Central

    Gerlis, L M; Schmidt-Ott, S C; Ho, S Y; Anderson, R H

    1993-01-01

    OBJECTIVE--Since 1905 there have been many reports of cases in which the right ventricle was deficient in myocardium. Several terms have been used to describe this condition. Of these, "Uhl's anomaly" and "arrhythmogenic right ventricular dysplasia" are most often used. Our study investigates the relation between these entities. METHOD--Five cases with a primary deficiency of the right ventricular musculature were examined. The findings were compared with those published reports to evaluate the similarities and differences between Uhl's anomaly and arrhythmogenic dysplasia. RESULTS--The five cases showed two patterns of myocardial deficiency in the right ventricle. On the one hand, the parietal wall was paper thin with complete absence of musculature and apposition of the endocardial and epicardial layers. On the other hand, patchy, localised fibrofatty tissue replacement was found within the parietal musculature. Evidence from our cases, combined with analysis of other publications, showed different modes and timing of clinical presentation of the patients with these two anatomical conditions, congestive heart failure or arrhythmia. CONCLUSIONS--The conditions variously described as Uhl's anomaly and arrhythmogenic dysplasia are separate and distinct morphological entities. Images PMID:8435240

  9. Inhaled Nitric Oxide Augments Left Ventricular Assist Device Capacity by Ameliorating Secondary Right Ventricular Failure.

    PubMed

    Lovich, Mark A; Pezone, Matthew J; Wakim, Matthew G; Denton, Ryan J; Maslov, Mikhail Y; Murray, Michael R; Tsukada, Hisashi; Agnihotri, Arvind K; Roscigno, Robert F; Gamero, Lucas G; Gilbert, Richard J

    2015-01-01

    Clinical right ventricular (RV) impairment can occur with left ventricular assist device (LVAD) use, thereby compromising the therapeutic effectiveness. The underlying mechanism of this RV failure may be related to induced abnormalities of septal wall motion, RV distension and ischemia, decreased LV filling, and aberrations of LVAD flow. Inhaled nitric oxide (NO), a potent pulmonary vasodilator, may reduce RV afterload, and thereby increase LV filling, LVAD flow, and cardiac output (CO). To investigate the mechanisms associated with LVAD-induced RV dysfunction and its treatment, we created a swine model of hypoxia-induced pulmonary hypertension and acute LVAD-induced RV failure and assessed the physiological effects of NO. Increased LVAD speed resulted in linear increases in LVAD flow until pulse pressure narrowed. Higher speeds induced flow instability, LV collapse, a precipitous fall of both LVAD flow and CO. Nitric oxide (20 ppm) treatment significantly increased the maximal achievable LVAD speed, LVAD flow, CO, and LV diameter. Nitric oxide resulted in decreased pulmonary vascular resistance and RV distension, increased RV ejection, promoted LV filling and improved LVAD performance. Inhaled NO may thus have broad utility for the management of biventricular disease managed by LVAD implantation through the effects of NO on LV and RV wall dynamics. PMID:25710771

  10. A Physiological Controller for Turbodynamic Ventricular Assist Devices Based on Left Ventricular Systolic Pressure.

    PubMed

    Petrou, Anastasios; Ochsner, Gregor; Amacher, Raffael; Pergantis, Panagiotis; Rebholz, Mathias; Meboldt, Mirko; Schmid Daners, Marianne

    2016-09-01

    The current article presents a novel physiological feedback controller for turbodynamic ventricular assist devices (tVADs). This controller is based on the recording of the left ventricular (LV) pressure measured at the inlet cannula of a tVAD thus requiring only one pressure sensor. The LV systolic pressure (SP) is proposed as an indicator to determine the varying perfusion requirements. The algorithm to extract the SP from the pump inlet pressure signal used for the controller to adjust the speed of the tVAD shows robust behavior. Its performance was evaluated on a hybrid mock circulation. The experiments with changing perfusion requirements were compared with a physiological circulation and a pathological one assisted with a tVAD operated at constant speed. A sensitivity analysis of the controller parameters was conducted to identify their limits and their influence on a circulation. The performance of the proposed SP controller was evaluated for various values of LV contractility, as well as for a simulated pressure sensor drift. The response of a pathological circulation assisted by a tVAD controlled by the introduced SP controller matched the physiological circulation well, while over- and underpumping events were eliminated. The controller presented a robust performance during experiments with simulated pressure sensor drift. PMID:27645395

  11. Effect of Continued Cardiac Resynchronization Therapy on Ventricular Arrhythmias After Left Ventricular Assist Device Implantation.

    PubMed

    Schleifer, John William; Mookadam, Farouk; Kransdorf, Evan P; Nanda, Udai; Adams, Jonathon C; Cha, Stephen; Pajaro, Octavio E; Steidley, David Eric; Scott, Robert L; Carvajal, Tomas; Saadiq, Rayya A; Srivathsan, Komandoor

    2016-08-15

    Cardiac resynchronization therapy (CRT) reduces ventricular arrhythmia (VA) burden in some patients with heart failure, but its effect after left ventricular assist device (LVAD) implantation is unknown. We compared VA burden in patients with CRT devices in situ who underwent LVAD implantation and continued CRT (n = 39) to those who had CRT turned off before discharge (n = 26). Implantable cardioverter-defibrillator (ICD) shocks were significantly reduced in patients with continued CRT (1.5 ± 2.7 shocks per patient vs 5.5 ± 9.3 with CRT off, p = 0.014). There was a nonsignificant reduction in cumulative VA episodes per patient with CRT continued at discharge (42 ± 105 VA per patient vs 82 ± 198 with CRT off, p = 0.29). On-treatment analysis by whether CRT was on or off identified a significantly lower burden of VA (17 ± 1 per patient-year CRT on vs 37 ± 1 per patient-year CRT off, p <0.0001) and ICD shocks (1.2 ± 0.3 per patient-year CRT on vs 1.7 ± 0.3 per patient-year CRT off, p = 0.018). In conclusion, continued CRT is associated with significantly reduced ICD shocks and VA burden after LVAD implantation. PMID:27328958

  12. Early repolarization as a predictor of premature ventricular beats.

    PubMed

    Matoshvili, Z T; Petriashvili, Sh G; Archadze, A T; Azaladze, I G

    2015-02-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. Aim of this observational study was to compare number of premature ventricular beats in the different groups of patients with early repolarization. The result of this observational study shows that there are: 1,74 fold higher number of premature ventricular beats in 41-74 year subgroup VS 19-40 year subgroup; 1,31 fold higher number of premature ventricular beats in male subgroup VS female subgroup (But this difference is not statistically significant, because t=1,49, p=0,141); 2,85 fold higher number of premature ventricular beats in CAD+ERP subgroup VS ERP without CAD subgroup; 1,74 fold higher number of premature ventricular beats in HF+ERP subgroup VS ERP without HF subgroup; 1,81 fold higher number of premature ventricular beats in CAD+ERP subgroup VS CAD without ERP subgroup; 1,58 fold higher number of premature ventricular beats in HF+ERP subgroup VS HF without ERP subgroup; So, CAD+ERP is very arrhythmogenic condition, after this is HF+ERP, Then Age. This study shows that ERP independently increase number of PVB in different groups (CAD, HF). This is principally new and very important result. Also the number of patients is enough to make this conclusion.

  13. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device

    PubMed Central

    Bansal, Shelley; Rosas, Paola C.; Mazzaferri, Ernest L.; Sai-Sudhakar, Chittoor B.

    2016-01-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome. PMID:27034560

  14. Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction

    PubMed Central

    Kim, Tae Hoon; Shin, Yu Rim; Kim, Young Sam; Kim, Do Jung; Kim, Hyohyun; Shin, Hong Ju; Htut, Aung Thein; Park, Han Ki

    2015-01-01

    A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients. PMID:26665108

  15. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device.

    PubMed

    Ravi, Yazhini; Bansal, Shelley; Rosas, Paola C; Mazzaferri, Ernest L; Sai-Sudhakar, Chittoor B

    2016-04-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome. PMID:27034560

  16. Surgical considerations for the explantation of the Parachute left ventricular partitioning device and the implantation of the HeartMate II left ventricular assist device.

    PubMed

    Ravi, Yazhini; Bansal, Shelley; Rosas, Paola C; Mazzaferri, Ernest L; Sai-Sudhakar, Chittoor B

    2016-04-01

    Chronic heart failure is the leading cause of death in the world. With newer therapies, the burden of this disease has decreased; however, a significant number of patients remain refractive to existing therapies. Myocardial infarction often leads to ventricular remodeling and eventually contributes to heart failure. The Parachute™ (Cardiokinetix, Menlo Park, CA) is the first device designed for percutaneous ventricular restoration therapy, which reduces left ventricular volume and minimizes the risk of open surgical procedures. For the first time, we report a case of explantation of the Parachute ventricular partitioning device and transition to a HeartMate II™ left ventricular assist device and the surgical considerations for a successful outcome.

  17. Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction.

    PubMed

    Kim, Tae Hoon; Shin, Yu Rim; Kim, Young Sam; Kim, Do Jung; Kim, Hyohyun; Shin, Hong Ju; Htut, Aung Thein; Park, Han Ki

    2015-12-01

    A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients.

  18. Cardiac fibroblast GSK-3β regulates ventricular remodeling and dysfunction in ischemic heart

    PubMed Central

    Lal, Hind; Ahmad, Firdos; Zhou, Jibin; Yu, Justine E.; Vagnozzi, Ronald J.; Guo, Yuanjun; Yu, Daohai; Tsai, Emily J.; Woodgett, James; Gao, Erhe; Force, Thomas

    2014-01-01

    Background Myocardial infarction-induced remodeling includes chamber dilatation, contractile dysfunction, and fibrosis. Of these, fibrosis is the least understood. Following MI, activated cardiac fibroblasts (CFs) deposit extracellular matrix. Current therapies to prevent fibrosis are inadequate and new molecular targets are needed. Methods and Results Herein we report that GSK-3β is phosphorylated (inhibited) in fibrotic tissues from ischemic human and mouse heart. Using two fibroblast-specific GSK-3β knockout mouse models, we show that deletion of GSK-3β in CFs leads to fibrogenesis, left ventricular dysfunction and excessive scarring in the ischemic heart. Deletion of GSK-3β induces a pro-fibrotic myofibroblast phenotype in isolated CFs, in post-MI hearts, and in MEFs deleted for GSK-3β. Mechanistically, GSK-3β inhibits pro-fibrotic TGF-β1-SMAD-3 signaling via interactions with SMAD-3. Moreover, deletion of GSK-3β resulted in the suppression of SMAD-3 transcriptional activity. This pathway is central to the pathology since a small molecule inhibitor of SMAD-3 largely prevented fibrosis and limited LV remodeling. Conclusion These studies support targeting GSK-3β in myocardial fibrotic disorders and establish critical roles of CFs in remodeling and ventricular dysfunction. PMID:24899689

  19. EPICARDIAL AND INTRAMURAL EXCITATION DURING VENTRICULAR PACING: EFFECT OF MYOCARDIAL STRUCTURE

    PubMed Central

    Taccardi, Bruno; Punske, Bonnie B.; Macchi, Emilio; MacLeod, Robert S.; Ershler, Philip R.

    2009-01-01

    Published studies show that ventricular pacing in canine hearts produces three distinct patterns of epicardial excitation: elliptical isochrones near an epicardial pacing site, with asymmetrical bulges; areas with high propagation velocity, up to 2 or 3 m/s and numerous breakthrough sites; lower velocity areas (< 1 m/s) where excitation moves across the epicardial projection of the septum. With increasing pacing depth the magnitude of epicardial potential maxima becomes asymmetrical. The electrophysiological mechanisms that generate the distinct patterns have not been fully elucidated. In this study we investigated those mechanisms experimentally. Under pentobarbital anesthesia epicardial and intramural excitation isochrone and potential maps have been recorded from 22 exposed or isolated dog hearts, by means of epicardial electrode arrays and transmural plunge electrodes. In 5 experiments, a ventricular cavity was perfused with diluted Lugol solution. Results The epicardial bulges result from electrotonic attraction from the helically shaped subepicardial portions of the wave front. The high velocity patterns and the associated multiple breakthroughs are due to involvement of the Purkinje network. The low velocity at the septum crossing is due to the missing Purkinje involvement in that area. The asymmetric magnitude of the epicardial potential maxima and the shift of the breakthrough sites provoked by deep stimulation are a consequence of the epi-endocardial obliqueness of the intramural fibers. These results improve our understanding of intramural and epicardial propagation during PVCs and paced beats. This can be useful for interpreting epicardial maps recorded at surgery or inversely computed from body surface ECGs. PMID:18263708

  20. Adenosine triphosphate attenuates renal sympathetic nerve activity through left ventricular chemosensitive receptors.

    PubMed

    Taneyama, C; Benson, K T; Hild, P G; Goto, H

    1997-02-01

    We previously reported that ATP, but not adenosine, administered i.v. attenuates the baroreflex-mediated increase in sympathetic nerve activity in response to arterial hypotension by a vagal afferent mechanism. It was not elucidated in that study which vagal afferent endings are involved. Mongrel dogs were anesthetized with alpha-chloralose, thoracotomy was performed and a 27-gauge hypodermic needle was inserted into the left circumflex coronary artery. The left renal sympathetic nerves were isolated and placed on a bipolar silver electrode for measurement of renal sympathetic nerve activity (RSNA). Dose-response effects of intracoronary or i.v. infusion of ATP (100, 200 or 400 microg/kg/min) on RSNA and mean arterial pressure were studied in neuraxis-intact and cervically vagotomized dogs. RSNA was increased dose-dependently with decreasing mean arterial pressure during the i.v. ATP infusion. Elevation of RSNA was attenuated by higher intracoronary ATP infusion rates, despite the fact that mean arterial pressure was decreased dose-dependently. Left ventricular end-diastolic pressure, however, remained unchanged. This suppression of RSNA by the intracoronary ATP infusion was completely abolished by bilateral cervical vagotomy. Our data suggest that ATP attenuates reflex increases in sympathetic nerve activity by possibly stimulating ventricular chemoreceptors with cardiac vagal afferents. PMID:9023265

  1. [Hypothermia induced alteration of refractoriness in the ventricular myocardium of ground souirrel Citellus undulatus].

    PubMed

    Kuz'min, V S; Abramov, A A; Egorov, Iu V; Rozenshtraukh, L V

    2014-12-01

    Bioelectrical activity and refractoriness in ventricular myocardium of the hibernator--ground squirrel Citellus undulatus were investigated during hypothermia. Experiments were performed with use of isolated, perfused preparations of papillary muscle from right ventricular. Preparations were obtained from hibernating (HS), summer active (SAS) squirrels and from rats. Bioelectrical activity was registered using the standard microelectrode technique at 37-17 degrees C. Action potentials duration (APD), refractoriness duration (RD) and the velocity of the action potential wave front (dV/dt) were estimated. Hypothermia induced APD and RD prolongation were demonstrated in all groups of experimental animals. However, normalized RD was significantly longer in the HS group during hypothermia than in SAS and rats. Ratio of RD to APD in HS group exceeds unity at 17 degrees C, which allows to suggest so called "postrepolarization refractoriness" during hypothermia. Also, HS reveal more prominent preservation of dV/dt during hypothermia than SAS and rat. Significant prolongation of RD and maintenance of normal excitation conduction during hypothermia probably plays essential role in hibernators resistivity to cold induced arrhythmias.

  2. The Effects of Puerarin on Rat Ventricular Myocytes and the Potential Mechanism

    PubMed Central

    Xu, Hao; Zhao, Manxi; Liang, Shenghui; Huang, Quanshu; Xiao, Yunchuan; Ye, Liang; Wang, Qinyi; He, Longmei; Ma, Lanxiang; Zhang, Hua; Zhang, Li; Jiang, Hui; Ke, Xiao; Gu, Yuchun

    2016-01-01

    Puerarin, a known isoflavone, is commonly found as a Chinese herb medicine. It is widely used in China to treat cardiac diseases such as angina, cardiac infarction and arrhythmia. However, its cardioprotective mechanism remains unclear. In this study, puerarin significantly prolonged ventricular action potential duration (APD) with a dosage dependent manner in the micromolar range on isolated rat ventricular myocytes. However, submicromolar puerarin had no effect on resting membrane potential (RMP), action potential amplitude (APA) and maximal velocity of depolarization (Vmax) of action potential. Only above the concentration of 10 mM, puerarin exhibited more aggressive effect on action potential, and shifted RMP to the positive direction. Millimolar concentrations of puerarin significantly inhibited inward rectified K+ channels in a dosage dependent manner, and exhibited bigger effects upon Kir2.1 vs Kir2.3 in transfected HEK293 cells. As low as micromolar range concentrations of puerarin significantly inhibited Kv7.1 and IKs. These inhibitory effects may due to the direct inhibition of puerarin upon channels not via the PKA-dependent pathway. These results provided direct preclinical evidence that puerarin prolonged APD via its inhibitory effect upon Kv7.1 and IKs, contributing to a better understanding the mechanism of puerarin cardioprotection in the treatment of cardiovascular diseases. PMID:27762288

  3. An appreciation of some timing functions of a cardiac resynchronization device capable of left ventricular sensing.

    PubMed

    Barold, S Serge; Kucher, Andreas

    2016-09-01

    Some systems for cardiac resynchronization therapy (CRT) offer left ventricular sensing. This discussion with an illustrative case demonstrates that timing cycles in these devices may sometimes be difficult to understand because of left ventricular sensing. Programming of the left ventricular upper rate interval is crucial to optimize the resynchronization ability of the system. Interactions with the maximum sensor rate, the right ventricular upper rate interval, the left ventricular T wave protection algorithm, and the minimum ventricular tachycardia detection rate have to be considered. PMID:27605233

  4. Right Ventricular Tissue Doppler in Space Flight

    NASA Technical Reports Server (NTRS)

    Hamilton, Douglas R.; Barratt, Michael R.; Sargsyan, Ashot E.; Ebert, Douglas; Garcia, Kathleen M.; Martin, David S.; Dulchavsky, Scott A.; Duncan, J. Michael

    2009-01-01

    Tissue Doppler (TD) registers movement of a given sample of cardiac tissue throughout the cardiac cycle. TD spectra of the right ventricle (RV) were obtained from a long-duration ISS crewmember as a portion of an ongoing experiment ("Braslet" test objective). To our knowledge, this is the first report of RV TD conducted in space flight, and the data represent reproducibility and fidelity of this application in space and serve as the first "space normal" data set. Methods RV TD was performed by astronaut scientists remotely guided by an ultrasound expert from Mission Control Center, Houston, TX. In four of the subjects, RV TD was acquired from the free wall near the tricuspid annulus in two separate sessions 4 to 7 days apart. A fifth subject had only one session. All digital DICOM frames were exported for off-line analysis. Systolic (S ), early diastolic (E ) and late diastolic (A ) velocities were measured. RV Tei-index was calculated using diastolic and systolic time intervals as a combined measure of myocardial performance. Results and Discussion The mean values from the first 4 subjects (8 sessions) were used as the on-orbit reference data, and subject 5 was considered as a hypothetical patient for comparison (see Table). The greatest difference was in the early diastolic A (31 %) yet the standard deviation (a) for A amongst the reference subjects was 2.25 (mean = 16.02). Of interest is the Tei index, a simple and feasible indicator of overall ventricular function; it was similar amongst all the subjects. The late diastolic A seems to compensate for the variance in E . Normal Tei index for the RV is < 0.3, yet our data show all but one subject consistently above this level, notwithstanding their nominal responses to daily exercise in microgravity. These data remind us that the physiology of RV preload in altered gravity environments is still not completely understood.

  5. Voltage clamp experiments on ventricular myocardial fibres

    PubMed Central

    Beeler, G. W.; Reuter, H.

    1970-01-01

    1. A voltage clamp method utilizing a sucrose gap and glass microelectrodes was developed and used to study dog ventricular myocardial fibre bundles. The limitations and the reliability of this method are demonstrated by a series of tests. 2. A dynamic sodium current, excited at membrane potentials more positive than -65 mV, was measured. The equilibrium potential for this large, rapid inward current depends directly on [Na]o, shifting 29·0 ± 2·3 mV (± S.E. of mean), as opposed to a theoretically expected value of 30·6 mV, when [Na]o is reduced to 31% of normal. 3. Sodium current is inactivated by conditioning depolarizations. Complete inactivation occurs with conditioning potentials more positive than -45 mV, and 50% inactivation occurs at about -55 mV. The location of the inactivation curve shifts along the voltage axis, when [Ca]o is varied between 0·2 and 7·2 mM. 4. A second, much smaller and slower net inward current, with a threshold around -30 mV, and an equilibrium potential above +40 mV was also observed. 5. The `steady-state' current—voltage relationship (after 300-600 msec) exhibits inward-going (anomalous) rectification with negative slope between -50 and -25 mV. 6. A small, very slowly developing component of outward current was observed at inside positive potentials. The equilibrium potential for this current, although slightly dependent on [K]o, is neither identical with the potassium equilibrium potential nor with the resting potential in normal Tyrode solution. 7. Anatomical limitations, primarily resistance in the extracellular space within the bundle, prevent complete characterization of the rapid, large sodium current, but do not limit the application of the clamp method to the study of other, smaller and slower currents. The evidence for this is discussed extensively in the Appendix. PMID:5503866

  6. Genetic epidemiology of left ventricular hypertrophy

    PubMed Central

    Bella, Jonathan N; Göring, Harald HH

    2012-01-01

    Left ventricular (LV) hypertrophy is a strong independent predictor of increased cardiovascular morbidity and mortality in clinical and population-based samples. Clinical and hemodynamic stimuli to LV hypertrophy induce not only an increase in cardiac mass and wall thickness but also a fundamental reconfiguration of the protein, cellular and molecular components of the myocardium. Several studies have indicated that LV mass is influenced by genetic factors. The substantial heritability (h2) for LV mass in population-based samples of varying ethnicity indicates robust genetic influences on LV hypertrophy. Genome-wide linkage and association studies in diverse populations have been performed to identify genes influencing LV mass, and although several chromosomal regions have been found to be significantly associated with LV mass, the specific genes and functional variants contained in these chromosomal regions have yet to be identified. In addition, multiple studies have tried to link single-nucleotide polymorphisms (SNPs) in regulatory and pathway genes with common forms of LV hypertrophy, but there is little evidence that these genetic variations are functional. Up to this point in time, the results obtained in genetic studies are of limited clinical value. Much of the heritability remains unexplained, the identity of the underlying gene pathways, genes, and functional variants remains unknown, and the promise of genetically-based risk prediction and personalized medicine remain unfulfilled. However, molecular biological technologies continue to improve rapidly, and the long-term potential of sophisticated genetic investigations using these modern genomic technologies, coupled with smart study designs, remains intact. Ultimately, genetic investigations offer much promise for future prevention, early intervention and treatment of this major public health issue. PMID:23173100

  7. Air pollution effects on ventricular repolarization.

    PubMed

    Lux, Robert L; Pope, C Arden

    2009-05-01

    We conducted a retrospective study of a set of previously published electrocardiographic data to investigate the possible direct association between levels of particulate air pollution and changes in ventricular repolarization -- the cardiac electrophysiologic process that manifests itself as the T wave* of the electrocardiogram (ECG) and that is definitively linked to and responsible for increased arrhythmogenesis. The published findings from this data set demonstrated a clear cardiac effect, namely, a reduction in heart rate variability (HRV) parameter values with increased levels of particulate air pollution (Pope et al. 2004), suggesting possible arrhythmogenic effects. Given this positive finding and the well-established sensitivity of cardiac repolarization to physiologic, pharmacologic, and neurologic interventions, and in light of emerging novel tools for assessing repolarization, we hypothesized that high levels of particulate air pollution would alter repolarization independent of changes in heart rate and, consequently, would increase arrhythmogenic risk. The likely mechanism of any deleterious effects on repolarization would be alteration of sodium, calcium, and potassium channels. The channel's structure, function, and kinetics are responsible for generating the cellular action potentials, which, when summed over the entire heart, result in the waves recorded by the ECG. A positive finding would provide evidence that increased levels of air pollution may be directly linked to increases in arrhythmogenic risk and, potentially, sudden cardiac death. The study population consisted of 88 nonsmoking, elderly subjects in whom multiple, continuous, 24-hour, 2-channel ECG recordings were collected, along with blood samples to evaluate inflammatory mechanisms (not pursued in the current study). The concentration of fine particulate matter (PM2.5, particulate matter with an aerodynamic diameter < or = 2.5 microm) in daily samples was measured or estimated and

  8. Heterogeneity of Left Ventricular Signal Characteristics in Response to Acute Vagal Stimulation during Ventricular Fibrillation in Dogs

    PubMed Central

    Nazeri, Alireza; Elayda, MacArthur A.; Dragnev, Lubomir; Frank, Christopher M.; Qu, Jihong; Afonso, Valtino X.; Rasekh, Abdi; Saeed, Mohammad; Cheng, Jie; Shuraih, Mossaab; Massumi, Ali; Razavi, Mehdi

    2011-01-01

    Studies have shown that long-term vagal stimulation is protective against ventricular fibrillation; however, the effects of acute vagal stimulation during ventricular fibrillation in the normal heart have not been investigated. We examined the effects of acute vagal stimulation on ventricular fibrillation in a canine model. In 4 dogs, we induced 30-second periods of ventricular fibrillation by means of intraventricular pacing. During 2 of the 4 periods of fibrillation that we analyzed, vagal stimulation was delivered through electrodes in the caudal ends of the vagus nerves. Noncontact unipolar electrograms were recorded from 3 ventricular regions: the basal septum, apical septum, and lateral free wall. We then computed the most frequent cycle length, mean organization index, and mean electrogram amplitude for each region. During fibrillation, vagal stimulation shortened the most frequent cycle lengths in the basal septum (P=0.02) and apical septum (P=0.0001), but not in the lateral wall (P=0.46). In addition, vagal stimulation significantly reduced the mean organization indices in the apical septum (P <0.001) and lateral wall (P <0.001), but not in the basal septum (P=0.19). Furthermore, vagal stimulation raised the mean electrogram amplitude in the basal septum (P <0.01) but lowered it substantially in the apical septum (P=0.00005) and lateral wall (P=0.00003). We conclude that vagal stimulation acutely affects the characteristics of ventricular fibrillation in canine myocardium in a spatially heterogeneous manner. This nonuniformity of response may have implications with regard to manipulating the autonomic system as a means of modifying the substrate for ventricular dysrhythmias. PMID:22199421

  9. Correlation of Left Ventricular Diastolic Function and Left Ventricular Geometry in Patients with Obstructive Sleep Apnoea Syndrome

    PubMed Central

    Wang, J; Zhang, H; Wu, C; Han, J; Guo, Z; Jia, C; Yang, L; Hao, Y; Xu, K; Liu, X; Si, J

    2015-01-01

    ABSTRACT Background: The aim of this study is to evaluate the correlation of the left ventricular diastolic function and the left ventricular geometry in patients with obstructive sleep apnoea syndrome (OSAS) by echocardiography. Methods: The 181 patients diagnosed with OSAS were divided into the normal geometry group (NG), the concentric remodelling group (CR), the eccentric hypertrophy group (EH) and the concentric hypertrophy group (CH). Pearson correlation analysis and multiple linear regression analysis were performed toward the correlation of the left ventricular diastolic function and the left ventricular geometry. Results: The E peak in the EH and CH group was significantly reduced, with significant difference; the E/A, Em, Am and Em/Am was reduced in the order of the CR, EH and CH groups, while E/Em was increased, and the difference was significant. Pearson correlation analysis revealed that the Em/Am showed significant negative correlations with the left ventricular mass index (LVMI) [r = −0.419] and relative wall thickness (RWT) [r = −0.289], while the E/Em was significantly positively correlated with the LVMI (r = 0.638) and RWT [r = 0.328] (p < 0.001). Multiple linear regression analysis revealed that LVMI and RWT had influence on the Em/Am and E/Em (r2 = 0.402, r2 = 0.107, p < 0.001). The left ventricular diastolic dysfunction was the worst in the CH group. Conclusions: There was correlation between the left ventricular diastolic dysfunction and the changes in cardiac geometry. PMID:26360680

  10. Survival and complications following ventricular assist pumping for cardiogenic shock.

    PubMed Central

    Pennock, J L; Pierce, W S; Wisman, C B; Bull, A P; Waldhausen, J A

    1983-01-01

    Thirty patients (pts) have undergone ventricular assist pumping for up to 25.4 days (mean 6.8 days). Twenty-eight pts could not be weaned from cardiopulmonary bypass (CPB) after open heart operations and two pts sustained myocardial infarctions (MI), with cardiogenic shock unresponsive to medical therapy previous to surgery. Twenty-two pts required left ventricular assistance (LVA); 55% (12/22) were weaned from the pump and 32% (7/22) survived. Two pts required right ventricular assistance (RVA); both were weaned from the pump and survived. Six pts required right and left ventricular assistance (BVA) and none survived. Postoperative survival for program years 1976 through 1979 (14 pts) was 14% (2/14). Postoperative survival for program years 1980 through 1982 (16 pts) was 44% (7/16), reflecting improved pump insertion techniques (left atrial cannulation) and pt management. Since 1980, 12 pts have required LVA, nine have been weaned from the pump, and six pts have survived (50%). One pt has required RVA and has survived, and three pts requiring BVA did not survive. Seven pts have been alive and well 5, 9, 14, 19, 24, 30 and 36 months after surgery. Five are NYHA functional Class I status and two pts are NYHA Class II status. Current data indicates that single ventricular assistance in pts who cannot be weaned from CPB is "reasonable and therapeutic treatment to extend life." Images Fig. 1. PMID:6625718

  11. Experience with the Sarns centrifugal pump in postcardiotomy ventricular failure.

    PubMed

    Curtis, J J; Walls, J T; Schmaltz, R; Boley, T M; Nawarawong, W; Landreneau, R J

    1992-09-01

    The reported clinical use of the Sarns centrifugal pump (Sarns, Inc./3M, Ann Arbor, Mich.) as a cardiac assist device for postcardiotomy ventricular failure is limited. During a 25-month period ending November 1988, we used 40 Sarns centrifugal pumps as univentricular or biventricular cardiac assist devices in 27 patients who could not be weaned from cardiopulmonary bypass despite maximal pharmacologic and intraaortic balloon support. Eighteen men and nine women with a mean age of 60.4 years (28 to 83) required assistance. Left ventricular assist alone was used in 12 patients, right ventricular assist in 2, and biventricular assist in 13. The duration of assist ranged from 2 to 434 hours (median 45). Centrifugal assist was successful in weaning 100% of the patients. Ten of 27 patients (37%) improved hemodynamically, allowing removal of the device(s), and 5 of 27 (18.5%) survived hospitalization. Survival of patients requiring left ventricular assist only was 33.3% (4/12). Complications were common and included renal failure, hemorrhage, coagulopathy, ventricular arrhythmias, sepsis, cerebrovascular accident, and wound infection. During 3560 centrifugal pump hours, no pump thrombosis was observed. The Sarns centrifugal pump is an effective assist device when used to salvage patients who otherwise cannot be weaned from cardiopulmonary bypass. Statistical analysis of preoperative patient characteristics, operative risk factors, and postoperative complications failed to predict which patients would be weaned from cardiac assist or which would survive.

  12. Ventricular arrhythmias in congestive heart failure: clinical significance and management.

    PubMed Central

    Khoshnevis, G R; Massumi, A

    1999-01-01

    The benefit of defibrillator therapy has been well established for patients with LV dysfunction (ejection fraction less than 35%), coronary artery disease, NSVT, and inducible and nonsuppressible ventricular tachycardia. Implantable cardioverter-defibrillator therapy is also indicated for all CHF patients in NYHA functional classes I, II, and III who present with aborted sudden cardiac death, or ventricular fibrillation, or hemodynamically unstable ventricular tachycardia--and also in patients with syncope with no documented ventricular tachycardia but with inducible ventricular tachycardia at electrophysiology study. The ongoing MADIT II trial was designed to evaluate the benefit of prophylactic ICD implantation in these patients (ejection fraction less than 30%, coronary artery disease, and NSVT) without prior risk stratification by PES. The CABG Patch trial concluded that prophylactic placement of an ICD during coronary artery bypass grafting in patients with low ejection fraction and abnormal SAECG is not justifiable. Except for the indications described above, ICD implantation has not been proved to be beneficial as primary or secondary therapy. Until more data are available, patients should be encouraged to enroll in the ongoing clinical trials. PMID:10217470

  13. Idiopathic ventricular tachycardia: feasibility and efficacy of catheter ablation.

    PubMed

    Velazquez Rodriguez, E; Frank, R; Fontaine, G; Tonet, J; Lascault, G; Rosas, F; Eslami, M; Nakazato, Y

    1995-01-01

    Idiopathic ventricular tachycardia is a well described syndrome of both left and right ventricular origin. This study reports the feasibility and efficacy of catheter ablation in this entity. Fourteen patients (mean age 30 +/- 10 years of age) and six patients (mean age 51 +/- 9 years of age) underwent endocardial catheter ablation with either direct-current shocks and radiofrequency energy, respectively. Earliest right and left ventricular activation and endocardial mapping during tachycardia were made to localize the site of ventricular tachycardia origin. The overall clinical efficacy was 93% for direct-current method with a mean number of shocks of 3.3 +/- 0.9/patient after a mean follow-up of 38 +/- 25 months. Radiofrequency ablation achieved an overall clinical efficacy of 83.6% with a mean of 3.2 pulses/patient during a follow-up of 10.5 +/- 4 months. The isoenzyme MB fraction of peak creatine kinase after ablation was less than 5%. There were no complications in any patient who underwent radiofrequency energy. Endocardial catheter ablation is feasible in patients with idiopathic ventricular tachycardia. Both methods are highly effective but radiofrequency energy is most desirable because of its lack of barotrauma, and may be considered as early therapy. PMID:7620280

  14. Left ventricular systolic and diastolic function in hyperthyroidism

    SciTech Connect

    Friedman, M.J.; Okada, R.D.; Ewy, G.A.; Hellman, D.J.

    1982-12-01

    In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.

  15. Ventricular dysfunction following direct-current shock atrioventricular junction ablation.

    PubMed

    Warren, R J; Vohra, J K; Chan, W; Lichtenstein, M; Mond, H G; Hunt, D

    1991-02-01

    Catheter-induced His bundle ablation for refractory supraventricular arrhythmias is most commonly performed with direct-current shock energy of 200-300 joules. The high energy pulse delivered by direct-current shock produces a lesion in the atrioventricular node by fulguration, with the residual energy being dissipated as a pressure wave. The effect of direct-current shock His bundle ablation on global and regional ventricular function was assessed in 14 consecutive patients by radionuclide ventriculography performed before and after ablation and again three months later. All studies were performed with ventricular pacing at 110 bpm. Global left ventricular ejection fraction was found to be significantly reduced at the three month study (0.43 +/- 0.03 vs 0.50 +/- 0.03, pre ablation, p = 0.02). A significant reduction in wall-motion score was also seen in six of the seven patients who had normal wall motion in pacing rhythm prior to ablation. Deterioration was mainly seen at the left and right ventricular apices. The observed reduction in ventricular function that follows direct-current shock His bundle ablation may result from myocardial damage from electro-coagulation or from barotrauma and supports continued investigation into alternative, less traumatic energy sources for the procedure. PMID:2036072

  16. Ventricular dysfunction in children with obstructive sleep apnea: radionuclide assessment

    SciTech Connect

    Tal, A.; Leiberman, A.; Margulis, G.; Sofer, S.

    1988-01-01

    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% (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.

  17. Surgical ventricular restoration for the treatment of heart failure.

    PubMed

    Buckberg, Gerald; Athanasuleas, Constantine; Conte, John

    2012-12-01

    Heart failure (HF) is an emerging epidemic affecting 15 million people in the USA and Europe. HF-related mortality was unchanged between 1995 and 2009, despite a decrease in the incidence of cardiovascular disease. Conventional explanations include an aging population and improved treatment of acute myocardial infarction and HF. An adverse relationship between structure and function is the central theme in patients with systolic dysfunction. The normal elliptical ventricular shape becomes spherical in ischemic, valvular, and nonischemic dilated cardiomyopathy. Therapeutic decisions should be made on the basis of ventricular volume rather than ejection fraction. When left ventricular end-systolic volume index exceeds 60 ml/m², medical therapy, CABG surgery, and mitral repair have limited benefit. This form-function relationship can be corrected by surgical ventricular restoration (SVR), which returns the ventricle to a normal volume and shape. Consistent early and late benefits in the treatment of ischemic dilated cardiomyopathy with SVR have been reported in >5,000 patients from various international centers. The prospective, randomized STICH trial did not confirm these findings and the reasons for this discrepancy are examined in detail. Future surgical options for SVR in nonischemic and valvular dilated cardiomyopathy, and its integration with left ventricular assist devices and cell therapy, are described.

  18. Inhibition of premature ventricular extrastimuli by subthreshold conditioning stimuli.

    PubMed

    Skale, B T; Kallok, M J; Prystowsky, E N; Gill, R M; Zipes, D P

    1985-07-01

    The purpose of this study was to determine whether trains of subthreshold high frequency conditioning stimuli (333 Hz, 1 ms duration, 2 ms interval) delivered to the canine ventricle inhibited the response to a premature stimulus (S2) more effectively than did a single subthreshold conditioning stimulus. It was found that trains of conditioning stimuli (mean 1.21 mA) inhibited the response to S2 152 ms beyond expiration of the ventricular effective refractory period, whereas a single conditioning stimulus inhibited S2 only 20 ms or less beyond the ventricular effective refractory period. In late diastole, trains of conditioning stimuli failed to inhibit S2 when the train of stimuli caused ventricular depolarization or the latter occurred in response to the next sinus impulse. Trains of conditioning stimuli did not induce ventricular arrhythmias. Lidocaine or autonomic blockade did not alter the response to trains of conditioning stimuli. Trains of conditioning stimuli or a single conditioning stimulus inhibited the response to S2 only when they were delivered at the same electrode site. By lengthening the ventricular effective refractory period, trains of conditioning stimuli could prevent or terminate tachycardias, but this possibility is constrained, at present, by the spatial limitations of the technique.

  19. Positive T wave overshoot as a sign of ventricular enlargement.

    PubMed

    Short, D; Weir, J

    1984-03-01

    A consecutive series of 86 patients with an inverted T wave showing terminal positivity (overshoot) of a specific pattern in the resting electrocardiogram were studied. Patients with bundle branch block or electrocardiographic evidence of acute infarction and those taking digoxin or a similar drug were excluded. In 67 patients the heart was examined by echocardiography and in a further two by direct inspection. Sixty six of the 69 patients had an abnormal thickness of the left (or right) ventricle or a calculated left ventricular mass greater than 200 g. Seven of the patients examined by echocardiography had clinically pure ischaemic heart disease; all showed evidence of left ventricular enlargement. In only 39 of the 63 patients with anatomical evidence of left ventricular hypertrophy or dilatation did the electrocardiogram satisfy the standard voltage criterion of left ventricular hypertrophy. In the absence of acute infarction, bundle branch block, or digitalisation positive T wave overshoot of the pattern described is a sign of increased ventricular mass. PMID:6230092

  20. Ventricular dysfunction following direct-current shock atrioventricular junction ablation.

    PubMed

    Warren, R J; Vohra, J K; Chan, W; Lichtenstein, M; Mond, H G; Hunt, D

    1991-02-01

    Catheter-induced His bundle ablation for refractory supraventricular arrhythmias is most commonly performed with direct-current shock energy of 200-300 joules. The high energy pulse delivered by direct-current shock produces a lesion in the atrioventricular node by fulguration, with the residual energy being dissipated as a pressure wave. The effect of direct-current shock His bundle ablation on global and regional ventricular function was assessed in 14 consecutive patients by radionuclide ventriculography performed before and after ablation and again three months later. All studies were performed with ventricular pacing at 110 bpm. Global left ventricular ejection fraction was found to be significantly reduced at the three month study (0.43 +/- 0.03 vs 0.50 +/- 0.03, pre ablation, p = 0.02). A significant reduction in wall-motion score was also seen in six of the seven patients who had normal wall motion in pacing rhythm prior to ablation. Deterioration was mainly seen at the left and right ventricular apices. The observed reduction in ventricular function that follows direct-current shock His bundle ablation may result from myocardial damage from electro-coagulation or from barotrauma and supports continued investigation into alternative, less traumatic energy sources for the procedure.

  1. Acceleration of cerebral ventricular expansion in the Cardiovascular Health Study.

    PubMed

    Carmichael, Owen T; Kuller, L H; Lopez, O L; Thompson, P M; Dutton, R A; Lu, A; Lee, S E; Lee, J Y; Aizenstein, H J; Meltzer, C C; Liu, Y; Toga, A W; Becker, J T

    2007-09-01

    Interactions between prevalent late-life medical conditions and expansion of the cerebral ventricles are not well understood. Thirty elderly subjects received three magnetic resonance (MR) scans each, in 1997-1999, 2002-2004, and 2003-2005. A linear expansion model of MR-measured lateral ventricle volume was estimated for each subject by fitting a line to a plot of their 1997-1999 and 2002-2004 volumes as a function of time. Acceleration in ventricular expansion was defined as the deviation between the 2003-2005 volumes measured from MR and the 2003-2005 volumes predicted by the linear expansion model. Ventricular acceleration was analyzed in a multivariate model with age, race, history of heart disease, diabetes, and hypertension as fixed effects. Ventricular acceleration was significantly higher in non-whites, diabetics, and those without heart disease (p<0.05). Ventricular acceleration was higher in subjects with a history of hypertension, but the difference was not statistically significant (p=0.08). Acceleration of ventricular expansion in the elderly may be related to demographic and cardiovascular factors.

  2. Left ventricular systolic and diastolic function in hyperthyroidism.

    PubMed

    Friedman, M J; Okada, R D; Ewy, G A; Hellman, D J

    1982-12-01

    In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.

  3. Aspirate from human stented saphenous vein grafts induces epicardial coronary vasoconstriction and impairs perfusion and left ventricular function in rat bioassay hearts with pharmacologically induced endothelial dysfunction.

    PubMed

    Lieder, Helmut R; Baars, Theodor; Kahlert, Philipp; Kleinbongard, Petra

    2016-08-01

    Stent implantation into aortocoronary saphenous vein grafts (SVG) releases particulate debris and soluble vasoactive mediators, for example, serotonin. We now analyzed effects of the soluble mediators released into the coronary arterial blood during stent implantation on vasomotion of isolated rat epicardial coronary artery segments and on coronary flow and left ventricular developed pressure in isolated perfused rat hearts. Coronary blood was retrieved during percutaneous SVG intervention using a distal occlusion/aspiration protection device in nine symptomatic patients with stable angina pectoris and a flow-limiting SVG stenosis. The blood was separated into particulate debris and plasma. Responses to coronary plasma were determined in isolated rat epicardial coronary arteries and in isolated, constant pressure-perfused rat hearts (±nitric oxide synthase [NOS] inhibition and ±serotonin receptor blockade, respectively). Coronary aspirate plasma taken after stent implantation induced a stronger vasoconstriction of rat epicardial coronary arteries (52 ± 8% of maximal potassium chloride induced vasoconstriction [% KClmax = 100%]) than plasma taken before stent implantation (12 ± 8% of KClmax); NOS inhibition augmented this vasoconstrictor response (to 110 ± 15% and 24 ± 9% of KClmax). Coronary aspirate plasma taken after stent implantation reduced in isolated perfused rat hearts only under NOS inhibition coronary flow by 17 ± 3% and left ventricular developed pressure by 25 ± 4%. Blockade of serotonin receptors abrogated these effects. Coronary aspirate plasma taken after stent implantation induces vasoconstriction in isolated rat epicardial coronary arteries and reduces coronary flow and left ventricular developed pressure in isolated perfused rat hearts with pharmacologically induced endothelial dysfunction. PMID:27482071

  4. Prolongation of atrio-ventricular node conduction in a rabbit model of ischaemic cardiomyopathy: Role of fibrosis and connexin remodelling.

    PubMed

    Nisbet, Ashley M; Camelliti, Patrizia; Walker, Nicola L; Burton, Francis L; Cobbe, Stuart M; Kohl, Peter; Smith, Godfrey L

    2016-05-01

    Conduction abnormalities are frequently associated with cardiac disease, though the mechanisms underlying the commonly associated increases in PQ interval are not known. This study uses a chronic left ventricular (LV) apex myocardial infarction (MI) model in the rabbit to create significant left ventricular dysfunction (LVD) 8weeks post-MI. In vivo studies established that the PQ interval increases by approximately 7ms (10%) with no significant change in average heart rate. Optical mapping of isolated Langendorff perfused rabbit hearts recapitulated this result: time to earliest activation of the LV was increased by 14ms (16%) in the LVD group. Intra-atrial and LV transmural conduction times were not altered in the LVD group. Isolated AVN preparations from the LVD group demonstrated a significantly longer conduction time (by approximately 20ms) between atrial and His electrograms than sham controls across a range of pacing cycle lengths. This difference was accompanied by increased effective refractory period and Wenckebach cycle length, suggesting significantly altered AVN electrophysiology post-MI. The AVN origin of abnormality was further highlighted by optical mapping of the isolated AVN. Immunohistochemistry of AVN preparations revealed increased fibrosis and gap junction protein (connexin43 and 40) remodelling in the AVN of LVD animals compared to sham. A significant increase in myocyte-non-myocyte connexin co-localization was also observed after LVD. These changes may increase the electrotonic load experienced by AVN muscle cells and contribute to slowed conduction velocity within the AVN.

  5. Non-genetic Purification of Ventricular Cardiomyocytes from Differentiating Embryonic Stem Cells through Molecular Beacons Targeting IRX-4

    PubMed Central

    Ban, Kiwon; Wile, Brian; Cho, Kyu-Won; Kim, Sangsung; Song, Ming-Ke; Kim, Sang Yoon; Singer, Jason; Syed, Anum; Yu, Shan Ping; Wagner, Mary; Bao, Gang; Yoon, Young-sup

    2015-01-01

    Summary Isolation of ventricular cardiomyocytes (vCMs) has been challenging due to the lack of specific surface markers. Here we show that vCMs can be purified from differentiating mouse embryonic stem cells (mESCs) using molecular beacons (MBs) targeting specific intracellular mRNAs. We designed MBs (IRX4 MBs) to target mRNA encoding Iroquois homeobox protein 4 (Irx4), a transcription factor specific for vCMs. To purify mESC vCMs, IRX4 MBs were delivered into cardiomyogenically differentiating mESCs, and IRX4 MBs-positive cells were FACS-sorted. We found that, of the cells isolated, ∼98% displayed vCM-like action potentials by electrophysiological analyses. These MB-purified vCMs continuously maintained their CM characteristics as verified by spontaneous beating, Ca2+ transient, and expression of vCM-specific proteins. Our study shows the feasibility of isolating pure vCMs via cell sorting without modifying host genes. The homogeneous and functional ventricular CMs generated via the MB-based method can be useful for disease investigation, drug discovery, and cell-based therapies. PMID:26651608

  6. On the clinical characterization of impulse and suction force contributions by the diastolic left ventricular vortex

    NASA Astrophysics Data System (ADS)

    Martinez-Legazpi, Pablo; Alhama, Marta; Benito, Yolanda; Bermejo, Javier; Yotti, Raquel; Perez-David, Esther; Barrio, Alicia; Perez-Del-Villar, Candelas; Gonzalez-Mansilla, Ana; Fernandez-Aviles, Francisco; Del Alamo, Juan C.

    2012-11-01

    One of the fluid-dynamic mechanisms that characterize the diastolic phase of the cardiac cycle is the formation of a left ventricular (LV) vortex ring that has been proposed to improve LV filling. However, direct clinical quantification of the contribution of this vortex to LV filling is elusive. In this clinical study, we considered 20 patients with dilated cardiomyopathy (DCM) and 40 healthy volunteers. We have developed and validated a method that derives two-dimensional maps of the LV flow from standard color-Doppler sequences. This study employs the new imaging modality in combination with a vortex identification method and a panel method in order to isolate and estimate the direct contribution of the LV vortex to fluid impulse and suction force during filling in the healthy and diseased populations. Funded by NIH Grant R21HL108268.

  7. Onychomycosis due to Candida parapsilosis in a Child with Ventricular Septal Defect: An Unusual Predisposition

    PubMed Central

    Hosuru Subramanya, Supram; Hamal, Deependra; Nayak, Niranjan; Gokhale, Shishir

    2016-01-01

    Candida parapsilosis is emerging as a potential pathogen for onychomycosis. A 4-year-old male child with perimembranous ventricular septal defect (VSD) was admitted with features of cystitis and was treated with broad spectrum antibiotics. Two weeks later, he developed yellowish discoloration of nails of both hands. The sloughed out nail, on microscopy, showed numerous yeast forms that were identified as Candida parapsilosis by both phenotypic and genotypic methods. Antifungal sensitivity testing of the isolate was performed by microbroth dilution method in accordance with CLSI guidelines. Patient was successfully treated with topical amphotericin B and oral fluconazole. Thus, one should have a high index of suspicion of C. parapsilosis onychomycosis, especially when the patient is in the paediatric age group, presenting with unusual predisposing condition like congenital heart disease, and is on broad spectrum antibiotics. PMID:27195165

  8. Post craniotomy extra-ventricular drain (EVD) associated nosocomial meningitis: CSF diagnostic criteria.

    PubMed

    Muñoz-Gómez, Sigridh; Wirkowski, Elizabeth; Cunha, Burke A

    2015-01-01

    Because external ventricular drains (EVDs) provide access to cerebrospinal fluid (CSF), there is potential for EVD associated acute bacterial meningitis (EVD-AM). Post-craniotomy, in patients with EVDs, one or more CSF abnormalities are commonly present making the diagnosis of EVD-AM problematic. EVD-AM was defined as elevated CSF lactic acid (>6 nmol/L), plus CSF marked pleocytosis (>50 WBCs/mm(3)), plus a positive Gram stain (same morphology as CSF isolate), plus a positive CSF culture of neuropathogen (same morphology as Gram stained organism). We reviewed 22 adults with EVDs to determine if our four CSF parameters combined accurately identified EVD-AM. No single or combination of <4 CSF parameters correctly diagnosed or ruled out EVD-AM. Combined our four CSF parameters clearly differentiated EVD-AM from one case of pseudomeningitis due to E. cloacae. We conclude that our four CSF criteria combined are useful in diagnosing EVD-AM in adults.

  9. Three-dimensional CFD/MRI modeling reveals that ventricular surgical restoration improves ventricular function by modifying intraventricular blood flow.

    PubMed

    Khalafvand, S S; Zhong, L; Ng, E Y K

    2014-10-01

    Surgical ventricular restoration (SVR) is designed to normalize distorted ventricular shape and size in patients with left ventricular (LV) dysfunction and akinetic and dyskinetic segments. This study is aimed to quantify the characteristics of LV as a pump for a case before and after SVR, which is followed by coronary artery bypass grafting (CABG). We hypothesize that SVR+CABG improves heart flow. A patient with heart failure had magnetic resonance (MR) scans before and 4 months after SVR. LV endocardial geometries were semi-automated segmented and reconstructed using our customized algorithm. The arbitrary Lagrangian-Eulerian formulation of Navier-Stokes equations was solved to derive the flow patterns and calculate pressure differences in LV. After SVR, LV ejection fraction increased from 34% to 48% in patient but was still lower than normal (70%). Second, LV vortices were stronger than pre-surgery but still weaker than normal. The maximum pressure differences between ventricular base and apex increased from 180 to 400 Pa during diastole, from 252 to 560 Pa during systole, respectively. As anticipated, SVR reduced LV volumes and augmented LV ejection fraction. Three-dimensional CFD/MRI modeling suggests that improved diastolic and systolic ventricular function after SVR is associated with changes in intraventricular blood flow.

  10. Model for end-stage liver disease predicts right ventricular failure in patients with left ventricular assist devices.

    PubMed

    Yost, Gardner L; Coyle, Laura; Bhat, Geetha; Tatooles, Antone J

    2016-03-01

    High rates of right ventricular failure continue to affect postoperative outcomes in patients implanted with left ventricular assist devices (LVADs). Development of right ventricular failure and implantation with right ventricular assist devices is known to be associated with significantly increased mortality. The model for end-stage liver disease (MELD) score is an effective means of evaluating liver dysfunction. We investigated the prognostic utility of postoperative MELD on post-LVAD implantation outcomes. MELD scores, demographic data, and outcomes including length of stay, survival, and postoperative right ventricular failure were collected for 256 patients implanted with continuous flow LVADs. Regression and Kaplan-Meier analyses were used to investigate the relationship between MELD and all outcomes. Increased MELD score was found to be an independent predictor of both right heart failure and necessity for RVAD implantation (OR 1.097, CI 1.040-1.158, p = 0.001; OR 1.121, CI 1.015, p = 0.024, respectively). Patients with RV failure and who underwent RVAD implantation had reduced postoperative survival compared to patients with RV dysfunction (no RV failure = 651.4 ± 609.8 days, RV failure = 392.6 ± 444.8 days, RVAD = 89.3 ± 72.8 days; p < 0.001). In conclusion, MELD can be used to reliably predict postoperative right heart failure and the necessity for RVAD implantation. Those patients with RV failure and RVADs experience significantly increased postoperative mortality compared to those without RV dysfunction. PMID:26187243

  11. Laboratory Markers of Ventricular Arrhythmia Risk in Renal Failure

    PubMed Central

    2014-01-01

    Sudden cardiac death continues to be a major public health problem. Ventricular arrhythmia is a main cause of sudden cardiac death. The present review addresses the links between renal function tests, several laboratory markers, and ventricular arrhythmia risk in patients with renal disease, undergoing or not hemodialysis or renal transplant, focusing on recent clinical studies. Therapy of hypokalemia, hypocalcemia, and hypomagnesemia should be an emergency and performed simultaneously under electrocardiographic monitoring in patients with renal failure. Serum phosphates and iron, PTH level, renal function, hemoglobin and hematocrit, pH, inflammatory markers, proteinuria and microalbuminuria, and osmolarity should be monitored, besides standard 12-lead ECG, in order to prevent ventricular arrhythmia and sudden cardiac death. PMID:24982887

  12. Premature ventricular complex-induced chronic cough and cough syncope.

    PubMed

    Stec, S; Dabrowska, M; Zaborska, B; Bielicki, P; Maskey-Warzechowska, M; Tarnowski, W; Chazan, R; Kulakowski, P

    2007-08-01

    The present case study reports a case of chronic cough and cough syncope associated with frequent premature ventricular complexes (PVCs). Careful analysis of cough-related symptoms and ECG monitoring led to the suspicion of PVC-induced cough. A coincidence between PVCs and episodes of cough was also documented by a portable multichannel recorder. Moreover, Doppler echocardiography revealed a PVC-induced transient increase in the pulmonary artery blood flow. After exclusion of other possible aetiologies, complete relief of chronic cough and cough syncope was achieved by radiofrequency ablation of the arrhythmogenic focus located in the right ventricular outflow tract. Premature ventricular complexes should be considered as a cause of chronic cough and cough syncope and an interdisciplinary cooperation can lead to successful diagnosis and treatment of this condition.

  13. A case of arrhythmogenic right ventricular cardiomyopathy—Naxos disease

    PubMed Central

    Saravanan, R.R.; Amuthan, V.; Janarthanan, R.A.; Balasubramanian, S.; Mohamed, S. Naina

    2012-01-01

    We present a case of arrhythmogenic right ventricular cardiomyopathy (ARVC)—Naxos disease. The patient is 21-year-old male with no history of previous heart disease admitted in a private hospital for rhythm disorder in heart. The condition was diagnosed as ventricular tachycardia (VT) and was treated with cardioversion. The patient was referred to our hospital for further evaluation. On examination patient had palmoplantar keratoderma, wooly hair, and dystrophic nails. The cardiovascular system examination was clinically normal. His electrocardiogram showed epsilon wave in lead V1; echocardiography showed hypo-echogenic tissues in the right ventricular (RV) apex and free wall; magnetic resonance imaging (MRI) investigation revealed fibrofatty replacement of RV free wall and dyskinetic RV wall with diastolic outbulging. PMID:22572432

  14. Passive ventricular remodeling in cardiac disease: focus on heterogeneity

    PubMed Central

    Kessler, Elise L.; Boulaksil, Mohamed; van Rijen, Harold V. M.; Vos, Marc A.; van Veen, Toon A. B.

    2014-01-01

    Passive ventricular remodeling is defined by the process of molecular ventricular adaptation to different forms of cardiac pathophysiology. It includes changes in tissue architecture, such as hypertrophy, fiber disarray, alterations in cell size and fibrosis. Besides that, it also includes molecular remodeling of gap junctions, especially those composed by Connexin43 proteins (Cx43) in the ventricles that affect cell-to-cell propagation of the electrical impulse, and changes in the sodium channels that modify excitability. All those alterations appear mainly in a heterogeneous manner, creating irregular and inhomogeneous electrical and mechanical coupling throughout the heart. This can predispose to reentry arrhythmias and adds to a further deterioration into heart failure. In this review, passive ventricular remodeling is described in Hypertrophic Cardiomyopathy (HCM), Dilated Cardiomyopathy (DCM), Ischemic Cardiomyopathy (ICM), and Arrhythmogenic Cardiomyopathy (ACM), with a main focus on the heterogeneity of those alterations mentioned above. PMID:25566084

  15. Revascularization in severe left ventricular dysfunction.

    PubMed

    Velazquez, Eric J; Bonow, Robert O

    2015-02-17

    The highest-risk patients with heart failure with reduced ejection fraction are those with ischemic cardiomyopathy and severe left ventricular systolic dysfunction (ejection fraction≤35%). The cornerstone of treatment is guideline-driven medical therapy for all patients and implantable device therapy for appropriately selected patients. Surgical revascularization offers the potential for improved survival and quality of life, particularly in patients with more extensive multivessel disease and the greatest degree of left ventricular systolic dysfunction and remodeling. These are also the patients at greatest short-term risk of mortality with coronary artery bypass graft surgery. The short-term risks of surgery need to be balanced against the potential for long-term benefit. This review discusses the evolving data on the role of surgical revascularization, surgical ventricular reconstruction, and mitral valve surgery in this high-risk patient population.

  16. Polymer-based restoration of left ventricular mechanics.

    PubMed

    Lee, Randall J; Hinson, Andy; Helgerson, Sam; Bauernschmitt, Robert; Sabbah, Hani N

    2013-01-01

    Heart failure continues to be a major health care concern with relatively few options for severely advanced heart failure patients. The hallmark of heart failure is the progressive dilatation of the left ventricle, thinning of the left ventricular wall leading to increased wall stress and increased myocardial oxygen consumption. Applying Laplace's law to the failing dilated ventricle, left ventricular augmentation utilizes a tissue engineering strategy to increase wall thickness and reduce chamber diameter, resulting in a decrease in wall stress and improved left ventricular function. A review of the rationale for an in situ tissue engineering approach for this treatment of heart failure and early clinical results of the Algisyl-LVR™ program are presented. PMID:22469060

  17. Postinfarct Left Ventricular Remodelling: A Prevailing Cause of Heart Failure

    PubMed Central

    Galli, Alessio; Lombardi, Federico

    2016-01-01

    Heart failure is a chronic disease with high morbidity and mortality, which represents a growing challenge in medicine. A major risk factor for heart failure with reduced ejection fraction is a history of myocardial infarction. The expansion of a large infarct scar and subsequent regional ventricular dilatation can cause postinfarct remodelling, leading to significant enlargement of the left ventricular chamber. It has a negative prognostic value, because it precedes the clinical manifestations of heart failure. The characteristics of the infarcted myocardium predicting postinfarct remodelling can be studied with cardiac magnetic resonance and experimental imaging modalities such as diffusion tensor imaging can identify the changes in the architecture of myocardial fibers. This review discusses all the aspects related to postinfarct left ventricular remodelling: definition, pathogenesis, diagnosis, consequences, and available therapies, together with experimental interventions that show promising results against postinfarct remodelling and heart failure. PMID:26989555

  18. Noninvasive evaluation of ventricular hypertrophy in professional athletes.

    PubMed

    Roeske, W R; O'Rourke, R A; Klein, A; Leopold, G; Karliner, J S

    1976-02-01

    Athletes often exhibit ECG findings which are considered to be abnormal. Therefore, we used noninvasive graphic methods to study 42 active professional male basketball players, ranging in age from 21 to 31 years, without clinically evident heart disease. Of the 42, 11 (25%) met the Romhilt-Estes ECG voltage criteria for left ventricular hypertrophy, and 12 (29%) satisfied VCG criteria for left ventricular enlargement; nine (21%) had left ventricular hypertrophy by both methods. In 33 subjects (79%) the 0.04 sec vector in the horizontal plane was anterior, and 29 of these exhibited one or more standard criteria for right ventricular enlargement; the ECG and VCG were concordant for right ventricular hypertrophy in 16 subjects (38%). Submaximal treadmill exercise tests (Bruce protocol) were normal in eight athletes, while in one subject ventricular premature beats occurred during the test. In 24 of 25 athletes (96%) from whom phonocardiograms were obtained a third heart sound was recorded, while in 14 (56%), a fourth heart sound was present. Of the 14 athletes who had a fourth heart sound, 12 (86%) had either ECG or VCG evidence of ventricular hypertrophy. Only four of 23 athletes had an increased cardiothoracic ratio (greater than .50) on routine chest X-ray. Ten athletes and ten control subjects matched for height, weight and body surface area had echocardiograms satisfactory for analysis. The left ventricular end-diastolic dimension in the athletes averaged 53.7 +/- 1.3 (SE) mm compared with a value of 49.9 +/- 0.7 mm in the control subjects (P less than 0.02), and was increased (greater than or equal to 56 mm) in four. Left ventricular posterior wall thickness averaged 11.1 +/- 0.6 mm, compared with a value of 9.8 +/- 0.5 mm in the control subjects (P less than 0.05), and was increased (greater than or equal to 11 mm) in six athletes. The right ventricular end-diastolic dimension averaged 20.8 +/- 1.1 mm compared with a value of 12.9 +/- 2.2 mm in the controls (P

  19. Sudden death in right ventricular dysplasia with minimal gross abnormalities.

    PubMed

    Burke, A P; Robinson, S; Radentz, S; Smialek, J; Virmani, R

    1999-03-01

    Arrhythmogenic right ventricular cardiomyopathy is emerging as a relatively common cause of exercise-induced sudden death in the young. The diagnostic criteria at autopsy are, however, not fully established, leading to both over- and underdiagnosis. We report a young man and a young woman dying suddenly of right ventricular dysplasia during exercise, in whom the gross autopsy findings in the right ventricle were minimal or even absent. However, the histologic features in both right and left ventricles were typical of the disease, and consisted of fibrofatty infiltrates with typical myocyte degeneration of the right ventricle and subepicardial regions of the left ventricle. These cases illustrate that microscopic findings are diagnostic and may be present in the absence of gross findings. Marked fat replacement is not essential for the diagnosis of right ventricular dysplasia, and the right ventricle should be extensively sampled histologically in all cases of sudden unexpected death, especially those that are exercise related.

  20. Tunneling a Pulmonary Artery Graft: A Simplified Way to Insert and Remove a Temporary Right Ventricular Assist Device.

    PubMed

    Saxena, Pankaj; Marasco, Silvana F

    2015-12-01

    Right ventricular failure can occur early or late after left ventricular assist device implantation. Support with a right ventricular assist device is needed in patients whose right ventricular failure does not respond to conservative management. The use of a temporary right ventricular assist device can enable the recovery of right ventricular function and avoid the use of a more permanent biventricular assist device, which is associated with complications and higher costs. We present our technique of instituting temporary right ventricular assist device support in patients who have undergone left ventricular assist device implantation.

  1. β-Adrenergic stimulation and rapid pacing mutually promote heterogeneous electrical failure and ventricular fibrillation in the globally ischemic heart.

    PubMed

    Garg, Vivek; Taylor, Tyson; Warren, Mark; Venable, Paul; Sciuto, Katie; Shibayama, Junko; Zaitsev, Alexey

    2015-05-01

    Global ischemia, catecholamine surge, and rapid heart rhythm (RHR) due to ventricular tachycardia or ventricular fibrillation (VF) are the three major factors of sudden cardiac arrest (SCA). Loss of excitability culminating in global electrical failure (asystole) is the major adverse outcome of SCA with increasing prevalence worldwide. The roles of catecholamines and RHR in the electrical failure during SCA remain unclear. We hypothesized that both β-adrenergic stimulation (βAS) and RHR accelerate electrical failure in the globally ischemic heart. We performed optical mapping of the action potential (OAP) in the right ventricular (RV) and left (LV) ventricular epicardium of isolated rabbit hearts subjected to 30-min global ischemia. Hearts were paced at a cycle length of either 300 or 200 ms, and either in the presence or in the absence of β-agonist isoproterenol (30 nM). 2,3-Butanedione monoxime (20 mM) was used to reduce motion artifact. We found that RHR and βAS synergistically accelerated the decline of the OAP upstroke velocity and the progressive expansion of inexcitable regions. Under all conditions, inexcitability developed faster in the LV than in the RV. At the same time, both RHR and βAS shortened the time to VF (TVF) during ischemia. Moreover, the time at which 10% of the mapped LV area became inexcitable strongly correlated with TVF (R(2) = 0 .72, P < 0.0001). We conclude that both βAS and RHR are major factors of electrical depression and failure in the globally ischemic heart and may contribute to adverse outcomes of SCA such as asystole and recurrent/persistent VF.

  2. β-Adrenergic stimulation and rapid pacing mutually promote heterogeneous electrical failure and ventricular fibrillation in the globally ischemic heart

    PubMed Central

    Garg, Vivek; Taylor, Tyson; Warren, Mark; Venable, Paul; Sciuto, Katie; Shibayama, Junko

    2015-01-01

    Global ischemia, catecholamine surge, and rapid heart rhythm (RHR) due to ventricular tachycardia or ventricular fibrillation (VF) are the three major factors of sudden cardiac arrest (SCA). Loss of excitability culminating in global electrical failure (asystole) is the major adverse outcome of SCA with increasing prevalence worldwide. The roles of catecholamines and RHR in the electrical failure during SCA remain unclear. We hypothesized that both β-adrenergic stimulation (βAS) and RHR accelerate electrical failure in the globally ischemic heart. We performed optical mapping of the action potential (OAP) in the right ventricular (RV) and left (LV) ventricular epicardium of isolated rabbit hearts subjected to 30-min global ischemia. Hearts were paced at a cycle length of either 300 or 200 ms, and either in the presence or in the absence of β-agonist isoproterenol (30 nM). 2,3-Butanedione monoxime (20 mM) was used to reduce motion artifact. We found that RHR and βAS synergistically accelerated the decline of the OAP upstroke velocity and the progressive expansion of inexcitable regions. Under all conditions, inexcitability developed faster in the LV than in the RV. At the same time, both RHR and βAS shortened the time to VF (TVF) during ischemia. Moreover, the time at which 10% of the mapped LV area became inexcitable strongly correlated with TVF (R2 = 0 .72, P < 0.0001). We conclude that both βAS and RHR are major factors of electrical depression and failure in the globally ischemic heart and may contribute to adverse outcomes of SCA such as asystole and recurrent/persistent VF. PMID:25713306

  3. Predictors of right ventricular failure after left ventricular assist device implantation.

    PubMed

    Koprivanac, Marijan; Kelava, Marta; Sirić, Franjo; Cruz, Vincent B; Moazami, Nader; Mihaljević, Tomislav

    2014-12-01

    Number of left ventricular assist device (LVAD) implantations increases every year, particularly LVADs for destination therapy (DT). Right ventricular failure (RVF) has been recognized as a serious complication of LVAD implantation. Reported incidence of RVF after LVAD ranges from 6% to 44%, varying mostly due to differences in RVF definition, different types of LVADs, and differences in patient populations included in studies. RVF complicating LVAD implantation is associated with worse postoperative mortality and morbidity including worse end-organ function, longer hospital length of stay, and lower success of bridge to transplant (BTT) therapy. Importance of RVF and its predictors in a setting of LVAD implantation has been recognized early, as evidenced by abundant number of attempts to identify independent risk factors and develop RVF predictor scores with a common purpose to improve patient selection and outcomes by recognizing potential need for biventricular assist device (BiVAD) at the time of LVAD implantation. The aim of this article is to review and summarize current body of knowledge on risk factors and prediction scores of RVF after LVAD implantation. Despite abundance of studies and proposed risk scores for RVF following LVAD, certain common limitations make their implementation and clinical usefulness questionable. Regardless, value of these studies lies in providing information on potential key predictors for RVF that can be taken into account in clinical decision making. Further investigation of current predictors and existing scores as well as new studies involving larger patient populations and more sophisticated statistical prediction models are necessary. Additionally, a short description of our empirical institutional approach to management of RVF following LVAD implantation is provided. PMID:25559829

  4. Improvement of Right Ventricular Hemodynamics with Left Ventricular Endocardial Pacing during Cardiac Resynchronization Therapy

    PubMed Central

    HYDE, EOIN R.; BEHAR, JONATHAN M.; CROZIER, ANDREW; CLARIDGE, SIMON; JACKSON, TOM; SOHAL, MANAV; GILL, JASWINDER S.; O'NEILL, MARK D.; RAZAVI, REZA; RINALDI, CHRISTOPHER A.

    2016-01-01

    Background Cardiac resynchronization therapy (CRT) with biventricular epicardial (BV‐CS) or endocardial left ventricular (LV) stimulation (BV‐EN) improves LV hemodynamics. The effect of CRT on right ventricular function is less clear, particularly for BV‐EN. Our objective was to compare the simultaneous acute hemodynamic response (AHR) of the right and left ventricles (RV and LV) with BV‐CS and BV‐EN in order to determine the optimal mode of CRT delivery. Methods Nine patients with previously implanted CRT devices successfully underwent a temporary pacing study. Pressure wires measured the simultaneous AHR in both ventricles during different pacing protocols. Conventional epicardial CRT was delivered in LV‐only (LV‐CS) and BV‐CS configurations and compared with BV‐EN pacing in multiple locations using a roving decapolar catheter. Results Best BV‐EN (optimal AHR of all LV endocardial pacing sites) produced a significantly greater RV AHR compared with LV‐CS and BV‐CS pacing (P < 0.05). RV AHR had a significantly increased standard deviation compared to LV AHR (P < 0.05) with a weak correlation between RV and LV AHR (Spearman rs = −0.06). Compromised biventricular optimization, whereby RV AHR was increased at the expense of a smaller decrease in LV AHR, was achieved in 56% of cases, all with BV‐EN pacing. Conclusions BV‐EN pacing produces significant increases in both LV and RV AHR, above that achievable with conventional epicardial pacing. RV AHR cannot be used as a surrogate for optimizing LV AHR; however, compromised biventricular optimization is possible. The beneficial effect of endocardial LV pacing on RV function may have important clinical benefits beyond conventional CRT. PMID:27001004

  5. Noninvasive Cardiac Screening in Young Athletes With Ventricular Arrhythmias

    PubMed Central

    Steriotis, Alexandros Klavdios; Nava, Andrea; Rigato, Ilaria; Mazzotti, Elisa; Daliento, Luciano; Thiene, Gaetano; Basso, Cristina; Corrado, Domenico; Bauce, Barbara

    2013-01-01

    The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Results of ECG were normal in most athletes (85%). VAs were initially detected prevalently during exercise testing (85%) and in the remaining cases on ECG and Holter monitoring. Premature ventricular complexes disappeared during exercise in 56% of subjects. Premature ventricular complexes during Holter monitoring averaged 4,700 per day, predominantly monomorphic (88%), single, and/or in couplets (79%). The most important echocardiographic findings were mitral valve prolapse in 29 patients (20%), congenital heart disease in 4 (3%), and right ventricular regional kinetic abnormalities in 5 (3.5%). On cardiac magnetic resonance imaging, right ventricular regional kinetic abnormalities were detected in 9 of 30 athletes and were diagnostic of arrhythmogenic right ventricular cardiomyopathy in only 1 athlete. Overall, 30% of athletes were judged to have potentially dangerous VAs. In asymptomatic athletes with prevalently normal ECG, most VAs can be identified by adding an exercise test during preparticipation screening. In conclusion, cardiac screening with noninvasive examinations remains a fundamental tool for the identification of a possible pathologic substrate and for the characterization of electrical instability. PMID:23219000

  6. Transapical miniaturized ventricular assist device: Design and initial testing

    PubMed Central

    Slaughter, Mark S.; Giridharan, Guruprasad A.; Tamez, Dan; LaRose, Jeff; Sobieski, Mike A.; Sherwood, Leslie; Koenig, Steven C.

    2013-01-01

    Background Left ventricular assist devices are increasingly used to treat patients with advanced and otherwise refractory heart failure as bridge to transplant or destination therapy. We evaluated a new miniaturized left ventricular assist device that requires minimal surgery for implantation, potentially allowing implantation in earlier stage heart failure. Methods HeartWare (Miami Lakes, Fla) developed transapical miniaturized ventricular assist device. Acute (n = 4), 1-week (n = 2), and 30-day (n = 4) bovine model experiments evaluated hemodynamic efficacy and biocompatibility of the device, which was implanted through small left thoracotomy with single insertion at apex of left ventricle without cardiopulmonary bypass. The device outflow cannula was positioned across the aortic valve. The international normalized ratio was maintained between 2.0 and 2.5 with warfarin. Hemodynamic, echocardiographic, fluoroscopic, hematologic, and blood chemistry measurements were evaluated. Results The device was successfully implanted through the left ventricular apex in all 10 animals. The device was operated at 15,000 ± 1000 rpm (power consumption, 3.5–6.0 W). The device maintained normal end-organ perfusion with no significant hemolysis (0–30 mg/dL). There were no pump failures or device-related complications. At autopsy, no abnormalities were seen in endocardium, aortic valve leaflets, or aortic root. There was no evidence of thromboembolism or abnormalities in any peripheral end organs. Conclusions We successfully demonstrated feasibility of a novel intraventricular assist device that can be completely implanted through left ventricular apex. This transapical surgical approach eliminates needs for sternotomy, device pocket, cardiopulmonary bypass, ventricular coring, and construction of an outflow graft anastomosis. PMID:21320708

  7. Backscatter and attenuation characterization of ventricular myocardium

    NASA Astrophysics Data System (ADS)

    Gibson, Allyson Ann

    2009-12-01

    This Dissertation presents quantitative ultrasonic measurements of the myocardium in fetal hearts and adult human hearts with the goal of studying the physics of sound waves incident upon anisotropic and inhomogeneous materials. Ultrasound has been used as a clinical tool to assess heart structure and function for several decades. The clinical usefulness of this noninvasive approach has grown with our understanding of the physical mechanisms underlying the interaction of ultrasonic waves with the myocardium. In this Dissertation, integrated backscatter and attenuation analyses were performed on midgestational fetal hearts to assess potential differences in the left and right ventricular myocardium. The hearts were interrogated using a 50 MHz transducer that enabled finer spatial resolution than could be achieved at more typical clinical frequencies. Ultrasonic data analyses demonstrated different patterns and relative levels of backscatter and attenuation from the myocardium of the left ventricle and the right ventricle. Ultrasonic data of adult human hearts were acquired with a clinical imaging system and quantified by their magnitude and time delay of cyclic variation of myocardial backscatter. The results were analyzing using Bayes Classification and ROC analysis to quantify potential advantages of using a combination of two features of cyclic variation of myocardial backscatter over using only one or the other feature to distinguish between groups of subjects. When the subjects were classified based on hemoglobin A1c, the homeostasis model assessment of insulin resistance, and the ratio of triglyceride to high-density lipoprotein-cholesterol, differences in the magnitude and normalized time delay of cyclic variation of myocardial backscatter were observed. The cyclic variation results also suggested a trend toward a larger area under the ROC curve when information from magnitude and time delay of cyclic variation is combined using Bayes classification than when

  8. Continual electric field stimulation preserves contractile function of adult ventricular myocytes in primary culture.

    PubMed

    Berger, H J; Prasad, S K; Davidoff, A J; Pimental, D; Ellingsen, O; Marsh, J D; Smith, T W; Kelly, R A

    1994-01-01

    To model with greater fidelity the electromechanical function of freshly isolated heart muscle cells in primary culture, we describe a technique for the continual electrical stimulation of adult myocytes at physiological frequencies for several days. A reusable plastic cover was constructed to fit standard, disposable 175-cm2 tissue culture flasks and to hold parallel graphite electrodes along the long axis of each flask, which treated a uniform electric field that resulted in a capture efficiency of ventricular myocytes of 75-80%. Computer-controlled amplifiers were designed to be capable of driving a number of flasks concurrently, each containing up to 4 x 10(6) myocytes, over a range of stimulation frequencies (from 0.1 to 7.0 Hz) with reversal of electrode polarity after each stimulus to prevent the development of pH gradients around each electrode. Unlike quiescent, unstimulated myocytes, the amplitude of contraction, and velocities of shortening and relaxation did not change in myocytes paced at 3-5 Hz for up to 72 h. The maintenance of normal contractile function in paced myocytes required mechanical contraction per se, since paced myocytes that remained quiescent due to the inclusion of 2.5 microM verapamil in the culture medium for 48 h also exhibited a decline in contractility when paced after verapamil removal. Similarly, pacing increased peak calcium current compared with quiescent cells that had not been paced. Thus myocyte contraction at physiological frequencies induced by continual uniform electric field stimulation in short-term primary culture in defining medium maintains some biophysical parameters of myocyte phenotype that are similar to those observed in freshly isolated adult ventricular myocytes.

  9. Cancer stem cells from a rare form of glioblastoma multiforme involving the neurogenic ventricular wall

    PubMed Central

    2012-01-01

    Background The cancer stem cell (CSC) hypothesis posits that deregulated neural stem cells (NSCs) form the basis of brain tumors such as glioblastoma multiforme (GBM). GBM, however, usually forms in the cerebral white matter while normal NSCs reside in subventricular and hippocampal regions. We attempted to characterize CSCs from a rare form of glioblastoma multiforme involving the neurogenic ventricular wall. Methods We described isolating CSCs from a GBM involving the lateral ventricles and characterized these cells with in vitro molecular biomarker profiling, cellular behavior, ex vivo and in vivo techniques. Results The patient’s MRI revealed a heterogeneous mass with associated edema, involving the left subventricular zone. Histological examination of the tumor established it as being a high-grade glial neoplasm, characterized by polygonal and fusiform cells with marked nuclear atypia, amphophilic cytoplasm, prominent nucleoli, frequent mitotic figures, irregular zones of necrosis and vascular hyperplasia. Recurrence of the tumor occurred shortly after the surgical resection. CD133-positive cells, isolated from the tumor, expressed stem cell markers including nestin, CD133, Ki67, Sox2, EFNB1, EFNB2, EFNB3, Cav-1, Musashi, Nucleostemin, Notch 2, Notch 4, and Pax6. Biomarkers expressed in differentiated cells included Cathepsin L, Cathepsin B, Mucin18, Mucin24, c-Myc, NSE, and TIMP1. Expression of unique cancer-related transcripts in these CD133-positive cells, such as caveolin-1 and −2, do not appear to have been previously reported in the literature. Ex vivo organotypic brain slice co-culture showed that the CD133+ cells behaved like tumor cells. The CD133-positive cells also induced tumor formation when they were stereotactically transplanted into the brains of the immune-deficient NOD/SCID mice. Conclusions This brain tumor involving the neurogenic lateral ventricular wall was comprised of tumor-forming, CD133-positive cancer stem cells, which are likely

  10. Irukandji syndrome, catecholamines, and mid-ventricular stress cardiomyopathy.

    PubMed

    Tiong, Keith

    2009-03-01

    We present here the first reported case of mid-ventricular stress cardiomyopathy secondary to 'Irukandji syndrome', following envenomisation from a jellyfish. Carukia barnesi is a cubozoan or box jellyfish found in Far North Queensland, Australia prevalent during the warmer months of the year. It has been associated with 'Irukandji syndrome' as characterized by a sympathetic overdrive secondary to an excess of endogenous catecholamines release. There have been previous cases of sudden onset of left ventricular dysfunction and jellyfish. The author believes that this case is important because it highlights the possible association between the sudden release in catecholamines and stress cardiomyopathy. PMID:18801721

  11. Mechanisms of Ventricular Arrhythmias: From Molecular Fluctuations to Electrical Turbulence

    PubMed Central

    Qu, Zhilin; Weiss, James N.

    2015-01-01

    Ventricular arrhythmias have complex causes and mechanisms. Despite extensive investigation involving many clinical, experimental, and computational studies, effective biological therapeutics are still very limited. In this article, we review our current understanding of the mechanisms of ventricular arrhythmias by summarizing the state of knowledge spanning from the molecular scale to electrical wave behavior at the tissue and organ scales and how the complex nonlinear interactions integrate into the dynamics of arrhythmias in the heart. We discuss the challenges that we face in synthesizing these dynamics to develop safe and effective novel therapeutic approaches. PMID:25340965

  12. Determination of left ventricular mass through SPECT imaging

    NASA Astrophysics Data System (ADS)

    Zárate-Morales, A.; Rodríguez-Villafuerte, M.; Martínez-Rodríguez, F.; Arévila-Ceballos, N.

    1998-08-01

    An edge detection algorithm has been applied to estimate left ventricular (LV) mass from single photon emission computed tomography (SPECT) thallium-201 images. The algorithm was validated using SPECT images of a phantom. The algorithm was applied to 20 patient studies from the Hospital de Cardiologia, Centro Médico Nacional Siglo XXI. Left ventricular masses derived from the stress and redistribution studies were highly correlated (r=0.96). The average LV masses obtained were 162±37 g and 169±34 g in the redistribution and stress studies, respectively.

  13. Iron deficiency and hemolytic anemia reversed by ventricular septal myectomy.

    PubMed

    Thotakura, Sudhir; Costa, Steven M; Cable, Christian

    2015-10-01

    Hemolytic anemia has been reported to occur in the setting of aortic stenosis and prosthetic heart valves, but much more rarely in association with obstructive hypertrophic cardiomyopathy (HC). Of the few descriptions of hemolytic anemia secondary to HC, all but one case involved bacterial endocarditis contributing to left ventricular outflow tract obstruction. We present the case of a 67-year-old man with recurrent hemolytic anemia and HC, without infective endocarditis. Attempts at iron repletion and augmentation of beta-blocker therapy proved his anemia to be refractory to medical management. Ventricular septal myectomy led to the resolution of hemolysis, anemia, and its coexisting symptoms.

  14. Pathological Ventricular Remodeling: Mechanisms: Part 1 of 2

    PubMed Central

    Xie, Min; Burchfield, Jana S.; Hill, Joseph A.

    2013-01-01

    Despite declines in heart failure morbidity and mortality with current therapies, re-hospitalization rates remain distressingly high, impacting substantially on individuals, society, and the economy. As a result, the need for new therapeutic advances and novel medical devices is urgent. Disease-related left ventricular remodeling is a complex process involving cardiac myocyte growth and death, vascular rarefaction, fibrosis, inflammation, and electrophysiological remodeling. As these events are highly inter-related, targeting one single molecule or process may not be sufficient. Here, we review molecular and cellular mechanisms governing pathological ventricular remodeling. PMID:23877061

  15. Limitations to Chronic Right Ventricular Assist Device Support.

    PubMed

    Karimov, Jamshid H; Sunagawa, Gengo; Horvath, David; Fukamachi, Kiyotaka; Starling, Randall C; Moazami, Nader

    2016-08-01

    Failure of the right ventricle represents a significant clinical problem and may have different causes, with rates varying between 5% and 50% in patients supported by a left ventricular assist device (LVAD). However, treatment options and device development for right ventricular failure (RVF) have significantly lagged behind those for LVADs. Newer technologies designed or adapted for RV support are needed to provide adequate long-term circulatory support. In this review, we discuss (1) the significance of RVF and its physiologic implications, (2) device constraints affecting treatment options for RVF, and (3) implantable VADs potentially available for RV support. PMID:27106620

  16. A global perspective of arrhythmogenic right ventricular cardiomyopathy

    PubMed Central

    Elmaghawry, Mohamed; Alhashemi, Mohammed; Zorzi, Alessandro; Yacoub, Magdi H

    2012-01-01

    Abstract: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive inherited heart disease characterized by ventricular arrhythmias and sudden cardiac death especially in the young. ARVC has been traditionally associated with the Mediterranean basin, as many seminal studies on the disease have originated from research groups of this region. Today, however, numerous ARVC registries from all over the world emphasize that the disease does not have a specific racial or geographical predilection. This work provides a review on the global perspective of ARVC. PMID:24688993

  17. Ventricular assist devices: preparing for catastrophic environmental events.

    PubMed

    Bartell, Lisa A

    2005-09-01

    In the summer of 2004, Florida experienced 4 major hurricanes in a matter of weeks. These hurricanes left many Floridians without power and passable roads, interrupted communications, and destroyed some homes. During this time, Tampa General Hospital had 1 patient living at home with an implanted ventricular assist device. The patient had been discharged home only 2 weeks before hurricane Frances hit hard. Although the patient was able to stay at home and experienced no major problems with the device, there were several situations that taught us many lessons about caring for patients with ventricular assist devices during environmental catastrophic events.

  18. Ion beam sputter-etched ventricular catheter for hydrocephalus shunt

    NASA Technical Reports Server (NTRS)

    Banks, B. A. (Inventor)

    1983-01-01

    A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

  19. Androgenic anabolic steroids also impair right ventricular function.

    PubMed

    Kasikcioglu, Erdem; Oflaz, Huseyin; Umman, Berrin; Bugra, Zehra

    2009-05-01

    Chronic anabolic steroid use suppresses left ventricular functions. However, there is no information regarding the chronic effects of anabolic steroids on right ventricular function which also plays a key role in global cardiac function. The main objective of the present study was to investigate the effects of androgenic anabolic steroids usage among athletes on remodeling the right part of the heart. Androgenic-anabolic steroids-using bodybuilders had smaller diastolic velocities of both ventricles than drug-free bodybuilders and sedentary counterparts. This study shows that androgenic anabolic steroids-using bodybuilders exhibited depressed diastolic functions of both ventricles.

  20. Overview of left ventricular outpouchings on cardiac magnetic resonance imaging

    PubMed Central

    Kumar, Sanjeev

    2015-01-01

    Left ventricular outpouchings commonly include aneurysm, pseudoaneurysm, and diverticulum and are now being increasingly detected on imaging. Distinction between these entities is of prime importance to guide proper management as outcomes for these entities differ substantially. Chest radiograph is usually nonspecific in their diagnosis. Echocardiography, multi-detector computed tomography evaluation and angiography are helpful in the diagnosis with their inherit limitations. Cardiac magnetic resonance imaging (MRI) is emerging as a very useful tool that allows simultaneous anatomical and functional evaluation along with tissue characterization, which has diagnostic, theraputic and prognostic implications. This article gives an overview of left ventricular outpouchings with special emphasis on their differentiation using cardiac MRI. PMID:26675616

  1. EKG isolator

    NASA Technical Reports Server (NTRS)

    Palmer, E.; Rasquin, J. R.; Smith, H. E.

    1971-01-01

    Light beam transmits heartbeat signal from electrodes on patient to electrocardiograph without exposing patient to possible severe electrical shock. System provides complete isolation between patient and EKG instrumentation.

  2. Adjuvant therapy with methylene blue in the treatment of right ventricular failure after pulmonary embolectomy.

    PubMed

    Raikhelkar, Jayashree K; Milla, Federico; Darrow, Bruce; Scurlock, Corey

    2011-04-01

    Severe pulmonary embolism often leads to right ventricular failure after surgical embolectomy secondary to ischaemia reperfusion injury and acute lung injury (ALI). Acute right ventricular dysfunction is traditionally treated with inotropes and vasopressors to maintain cardiac output and coronary perfusion as well as selective pulmonary vasodilators to provide right ventricular afterload reduction. We report the first case of utilisation of methylene (MB) in a patient with acute right ventricular failure and vasoplegic shock after surgical pulmonary embolectomy. PMID:20952252

  3. Reversal of premature ventricular complex-induced cardiomyopathy following successful radiofrequency catheter ablation.

    PubMed

    Efremidis, Michalis; Letsas, Konstantinos P; Sideris, Antonios; Kardaras, Fotios

    2008-06-01

    Premature ventricular complex (PVC)-induced cardiomyopathy is an underappreciated cause of left-ventricular (LV) dysfunction. The present report describes the case of an elderly man with a very high burden of monomorphic PVCs and LV dysfunction. Elimination of the left ventricular focus following radiofrequency catheter ablation resulted in reversal of cardiomyopathy.

  4. Reversal of ventricular premature beat induced cardiomyopathy by radiofrequency catheter ablation.

    PubMed

    Blaauw, Y; Pison, L; van Opstal, J M; Dennert, R M; Heesen, W F; Crijns, H J G M

    2010-10-01

    Frequent monomorphic ventricular premature beats (VPBs) may lead to left ventricular dysfunction. We describe two patients with frequent monomorphic VPBs and dilated cardiomyopathy in whom left ventricular function normalised after elimination of the VPBs by radiofrequency catheter ablation. The recent literature on this topic is summarised and potential candidates for catheter ablation are discussed. (Neth Heart J 2010;18:493-8.).

  5. Short Communication: Conformal Therapy for Peri-Ventricular Brain Tumors: Is Target Volume Deformation an Issue?

    SciTech Connect

    Bauman, Glenn Woodford, Curtis; Yartsev, Slav

    2008-04-01

    Physiologic variations in ventricular volumes could have important implications for treating patients with peri-ventricular brain tumors, yet no data exist in the literature addressing this issue. Daily megavoltage computed tomography (CT) scans in a patient with neurocytoma receiving fractionated radiation revealed minimal changes, suggesting that margins accounting for ventricular deformation are not necessary.

  6. Ventricular septal defect and double-chambered right ventricle in an alpaca.

    PubMed

    Poser, Helen; Dalla Pria, Angela; De Benedictis, Giulia M; Stelletta, Calogero; Berlanda, Michele; Guglielmini, Carlo

    2015-03-01

    A 20-month-old male alpaca was referred for evaluation of a cardiac murmur evident since birth. Echocardiography identified a ventricular septal defect (VSD) and a fibro-muscular band causing a stenosis of the right ventricular outflow tract. Right ventricular catheterization and selective angiography confirmed the diagnosis of VSD and double-chambered right ventricle with bidirectional shunting.

  7. Parasympathetic neurons in the cranial medial ventricular fat pad on the dog heart selectively decrease ventricular contractility.

    PubMed

    Dickerson, L W; Rodak, D J; Fleming, T J; Gatti, P J; Massari, V J; McKenzie, J C; Gillis, R A

    1998-05-28

    We hypothesized that selective control of ventricular contractility might be mediated by postganglionic parasympathetic neurons in the cranial medial ventricular (CMV) ganglion plexus located in a fat pad at the base of the aorta. Sinus rate, atrioventricular (AV) conduction (ventricular rate during atrial pacing), and left ventricular contractile force (LV dP/dt during right ventricular pacing) were measured in eight chloralose-anesthetized dogs both before and during bilateral cervical vagus stimulation (20-30 V, 0.5 ms pulses, 15-20 Hz). Seven of these dogs were tested under beta-adrenergic blockade (propranolol, 0.8 mg kg(-1) i.v.). Control responses included sinus node bradycardia or arrest during spontaneous rhythm, high grade AV block or complete heart block, and a 30% decrease in contractility from 2118 +/- 186 to 1526 +/- 187 mm Hg s(-1) (P < 0.05). Next, the ganglionic blocker trimethaphan (0.3-1.0 ml of a 50 microg ml(-1) solution) was injected into the CMV fat pad. Then vagal stimulation was repeated, which now produced a relatively small 5% (N.S., P > 0.05) decrease in contractility but still elicited the same degree of sinus bradycardia and AV block (N = 8, P < 0.05). Five dogs were re-tested 3 h after trimethaphan fat pad injection, at which time blockade of vagally-induced negative inotropy was partially reversed, as vagal stimulation decreased LV dP/dt by 19%. The same dose of trimethaphan given either locally into other fat pads (PVFP or IVC-ILA) or systemically (i.v.) had no effect on vagally-induced negative inotropy. Thus, parasympathetic ganglia located in the CMV fat pad mediated a decrease in ventricular contractility during vagal stimulation. Blockade of the CMV fat pad had no effect on vagally-mediated slowing of sinus rate or AV conduction.

  8. Heart rate variability in isolated rabbit hearts.

    PubMed

    Frey, B; Heger, G; Mayer, C; Kiegler, B; Stöhr, H; Steurer, G

    1996-11-01

    The presence of heart rate variability (HRV) in patients with cardiac denervation after heart transplantation raised our interest in HRV of isolated, denervated hearts. Hearts from seven adult white ELCO rabbits were transferred to a perfusion apparatus. All hearts were perfused in the working mode and in the Langendorff mode for 20 minutes each. HRV was analyzed in the frequency domain. A computer simulated test ECG at a constant rate of 2 Hz was used for error estimation of the system. In the isolated, denervated heart, HRV was of random, broadband fluctuations, different from the well-characterized oscillations at specific frequencies in intact animals. Mean NN was 423 +/- 51 ms in the Langendorff mode, 406 +/- 33 ms in the working heart mode, and 500 ms in the test ECG. Total power was 663 +/- 207 ms2, 817 +/- 318 ms2, and 3.7 ms2, respectively. There was no significant difference in any measure of HRV between Langendorff and working heart modes. The data provide evidence for the presence of HRV in isolated, denervated rabbit hearts. Left atrial and ventricular filling, i.e., the working heart mode, did not alter HRV, indicating that left atrial or ventricular stretch did not influence the sinus nodal discharge rate.

  9. Regional myocardial shape and dimensions of the working isolated canine left ventricle

    NASA Technical Reports Server (NTRS)

    Ritman, E.; Tsuiki, K.; Donald, D.; Wood, E. H.

    1975-01-01

    Angiographic experiments were performed on isolated canine left ventricle preparations using donor dog to supply blood to the coronary circulation via a rotary pump to control coronary flow. The angiographic record was transferred from video tape to video disk for detailed uninterrupted sequential analysis at a frequency of 60 fields/sec. It is shown that the use of a biplane X-ray technique and a metabolically supported isolated canine left ventricle preparation provides an angiographically ideal means of measuring the mechanical dynamics of the myocardium while the intact left ventricular myocardial structure and electrical activation pattern retain most of the in situ ventricular characteristics. In particular, biplane X-ray angiography of the left ventricle can provide estimates of total ventricular function such as ejection fraction, stroke volume, and myocardial mass correct to within 15% under the angiographically ideal conditions of the preparation.

  10. The feasibility and efficacy of right ventricular assistance without thoracotomy.

    PubMed

    Yano, M; Matsuo, K; Hatane, T; Araki, K; Onitsuka, T; Shibata, K; Koga, Y

    1993-01-01

    Mechanical right ventricular assistance has never been percutaneously instituted. We invented a new method for administering right ventricular assistance without thoracotomy (RAWT) and evaluated its effects in acute experiments using dogs. To institute RAWT, an outflow cannula was inserted into the pulmonary artery from the femoral vein, and an inflow cannula was inserted into the right atrium from the right jugular vein. A Swan-Ganz catheter inserted into the outflow cannula led it to the pulmonary artery under blood pressure monitoring only. A Sarns' centrifugal pump was used as a blood pump. We applied this system to biventricular failed hearts supported by a left ventricular assist device. We could increase cardiac output from 53.3 +/- 31.8 to 77.8 +/- 31.7 ml/min/kg, and mean aortic pressure from 43.5 +/- 12.3 to 57.5 +/- 11.2 mm Hg with RAWT. The right ventricular unloading effect of RAWT was not disturbed by regurgitation through the pulmonary or tricuspid valve.

  11. Perventricular closure of a perimembranous ventricular septal defect.

    PubMed

    Schreiber, Christian; Nöbauer, Christian; Zhang, Fengwei; Zhuang, Zhongyun

    2013-01-01

    In recent years, perventricular ventricular septal defect device closure without cardiopulmonary bypass has gained increasing acceptance in China. Under transoesophageal echocardiography guidance, muscular, perimembranous and even doubly committed defects are closed. We performed the first application of this technique outside of China and explain step-by-step the hybrid procedure.

  12. Advances in Modeling Ventricular Arrhythmias: from Mechanisms to the Clinic

    PubMed Central

    Trayanova, Natalia A.; Boyle, Patrick M.

    2014-01-01

    Modern cardiovascular research has increasingly recognized that heart models and simulation can help interpret an array of experimental data and dissect important mechanisms and interrelationships, with developments rooted in the iterative interaction between modeling and experimentation. This article reviews the progress made in simulating cardiac electrical behavior at the level of the organ and, specifically, in the development of models of ventricular arrhythmias and fibrillation, as well as their termination (defibrillation). The ability to construct multi-scale models of ventricular arrhythmias, representing integrative behavior from the molecule to the entire organ, has enabled mechanistic inquiry into the dynamics of ventricular arrhythmias in the diseased myocardium, in understanding drug-induced pro-arrhythmia, and in the development of new modalities for defibrillation, to name a few. In this article we also review the initial use of ventricular models of arrhythmia in personalized diagnosis, treatment planning, and prevention of sudden cardiac death. Implementing individualized cardiac simulations at the patient bedside is poised to become one of the most thrilling examples of computational science and engineering approaches in translational medicine. PMID:24375958

  13. Left ventricular function impairment in pregnancy-induced hypertension.

    PubMed

    Vázquez Blanco, M; Roisinblit, J; Grosso, O; Rodriguez, G; Robert, S; Berensztein, C S; Vega, H R; Lerman, J

    2001-03-01

    The changes induced by transient hypertension on cardiac structure and function are unclear. Pregnancy-induced hypertension offers a natural and spontaneous model of this condition. To assess the potential of echocardiographic Doppler to unmask left ventricular function impairment, we studied 28 women aged 26.4 +/- 7.2 years with pregnancy-induced hypertension defined as blood pressure higher than 140/90 mm Hg in the third trimester of pregnancy without a history of hypertension. Twenty normal pregnant women, aged 27.5 +/- 6.4 years, were the controls. Left ventricular diastolic diameter, fractional shortening, E velocity, A velocity, E/A ratio, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), ejection time (ET), and the combined index of myocardial performance (Tei index = IRT + ICT/ET), were calculated by echocardiography Doppler 2 to 4 days postpartum. There were statistically significant differences between groups in the following parameters: E/A ratio: 1.3 +/- 0.3 in pregnancy-induced hypertension v 1.5 +/- 0.3 in normal pregnant women (P < .05), IRT: 104 +/- 14 msec v 84 +/- 7 msec (P < .000), and the Tei index: 0.51 +/- 0.15 v 0.35 +/- 0.04 (P < .00), respectively. According to this data pregnancy-induced hypertension evaluated 2 to 4 days after delivery showed left ventricular dysfunction, mainly diastolic. The IRT and the Tei index are the most useful echocardiographic parameters to unmask left ventricular dysfunction in pregnancy-induced hypertension.

  14. Cardiac cryosurgery: regional myocardial blood flow of ventricular cryolesions

    SciTech Connect

    Holman, W.L.; Ikeshita, M.; Lease, J.G.; Smith, P.K.; Ungerleider, R.M.; Cox, J.L.

    1986-11-01

    Cryosurgery is one of three methods introduced recently for the treatment of ventricular tachyarrhythmias. Cryothermic exposure ablates arrhythmogenic ventricular myocardium, and produces a dense fibrous scar with a sharp border to histologically normal tissue. Myocardial blood flow in the region of the cryolesion, however, has not been quantitated. The purpose of this study was to measure regional blood flow within and around the cryolesion in an attempt to identify ischemic zones that might become arrhythmogenic. Left ventricular cryolesions were created in eleven adult dogs. Two weeks later, the animals underwent radioactive tracer microsphere injection for quantitation of regional myocardial blood flow. The fibrotic cryolesion demonstrated a significantly depressed blood flow (0.44 +/- 0.07 ml/min/g) compared to blood flow in control tissue (1.36 +/- 0.12 ml/min/g) (P less than 0.001). A 1-mm strip of myocardium immediately adjacent to the cryolesion, as well as other myocardium surrounding and subjacent to the cryolesion, did not show a significant decrease in regional blood flow. The border between the fibrotic cryolesion and the surrounding myocardium is, therefore, sharply defined not only in terms of histology but also in regards to regional blood flow. These data lend further support to the safe clinical use of cryothermia in the treatment of refractory ventricular tachycardia.

  15. Laparoscopic repair of diaphragmatic hernia after left ventricular assist device.

    PubMed

    Farma, Jeffrey; Leeser, David; Furukawa, Satoshi; Dempsey, Daniel T

    2003-06-01

    This case report describes a patient with a symptomatic diaphragmatic hernia that developed after orthotopic heart transplantation and explantation of a left ventricular assist device. The hernia was repaired laparoscopically, and at 6-month follow-up, she is without evidence of recurrence.

  16. Towards the development of a pediatric ventricular assist device.

    PubMed

    Borovetz, Harvey S; Badylak, Stephen; Boston, J Robert; Johnson, Carl; Kormos, Robert; Kameneva, Marina V; Simaan, Marwan; Snyder, Trevor A; Tsukui, Hiro; Wagner, William R; Woolley, Joshua; Antaki, James; Diao, Chenguang; Vandenberghe, Stijn; Keller, Bradley; Morell, Victor; Wearden, Peter; Webber, Steven; Gardiner, Jeff; Li, Chung M; Paden, Dave; Paden, Bradley; Snyder, Shaun; Wu, Jingchun; Bearnson, Gill; Hawkins, John A; Jacobs, Gordon; Kirk, John; Khanwilkar, Pratap; Kouretas, Peter C; Long, James; Shaddy, R E

    2006-01-01

    The very limited options available to treat ventricular failure in children with congenital and acquired heart diseases have motivated the development of a pediatric ventricular assist device at the University of Pittsburgh (UoP) and University of Pittsburgh Medical Center (UPMC). Our effort involves a consortium consisting of UoP, Children's Hospital of Pittsburgh (CHP), Carnegie Mellon University, World Heart Corporation, and LaunchPoint Technologies, Inc. The overall aim of our program is to develop a highly reliable, biocompatible ventricular assist device (VAD) for chronic support (6 months) of the unique and high-risk population of children between 3 and 15 kg (patients from birth to 2 years of age). The innovative pediatric ventricular assist device we are developing is based on a miniature mixed flow turbodynamic pump featuring magnetic levitation, to assure minimal blood trauma and risk of thrombosis. This review article discusses the limitations of current pediatric cardiac assist treatment options and the work to date by our consortium toward the development of a pediatric VAD.

  17. Normalised radionuclide measures of left ventricular diastolic function.

    PubMed

    Lee, K J; Southee, A E; Bautovich, G J; Freedman, B; McLaughlin, A F; Rossleigh, M A; Hutton, B F; Morris, J G

    1989-01-01

    Abnormal left ventricular diastolic function is being increasingly recognised in patients with clinical heart failure and normal systolic function. A simple routine radionuclide measure of diastolic function would therefore be useful. To establish this, the relationship of peak diastolic filling rate (normalized for either end diastolic volume, stroke volume, or peak systolic emptying rate), and heart rate, age, and left ventricular ejection fraction was studied in 64 subjects with normal cardiovascular systems using routine gated heart pool studies. The peak filling rate, when normalized to end diastolic volume, correlated significantly with heart rate, age and left ventricular ejection fraction, whereas normalization to stroke volume correlated significantly to heart rate and age but not to left ventricular ejection fraction. Peak filling rate normalized for peak systolic emptying rate correlated with age only. Multiple regression equations were determined for each of the normalized peak filling rates in order to establish normal ranges for each parameter. When using peak filling rate normalized for end diastolic volume or stroke volume, appropriate allowance must be made for heart rate, age and ejection fraction. Peak filling rate normalized to peak ejection rate is a heart rate independent parameter which allows the performance of the patient's ventricle in diastole to be compared with its systolic function. It may be used in patients with normal systolic function to serially follow diastolic function or if age corrected, to screen for diastolic dysfunction. PMID:2540982

  18. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular bypass (assist) device. 870.3545 Section 870.3545 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545...

  19. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ventricular bypass (assist) device. 870.3545 Section 870.3545 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545...

  20. Electronic circuit detects left ventricular ejection events in cardiovascular system

    NASA Technical Reports Server (NTRS)

    Gebben, V. D.; Webb, J. A., Jr.

    1972-01-01

    Electronic circuit processes arterial blood pressure waveform to produce discrete signals that coincide with beginning and end of left ventricular ejection. Output signals provide timing signals for computers that monitor cardiovascular systems. Circuit operates reliably for heart rates between 50 and 200 beats per minute.

  1. Calcium-sensing receptor induces rat neonatal ventricular cardiomyocyte apoptosis

    SciTech Connect

    Sun Yihua; Liu Meina; Li Hong; Shi Sa; Zhao Yajun; Wang Rui; Xu Changqing . E-mail: syh200415@yahoo.com.cn

    2006-12-01

    The calcium-sensing receptor (CaSR) exists in many tissues, and its expression has been identified in rat cardiac tissue. However, Physiological importance and pathophysiological involvement of CaSR in homeostatic regulation of cardiac function are unclear. To investigate the relation of CaSR and apoptosis in cardiomyocytes, we examined the role of the CaSR activator gadolinium chloride (GdCl{sub 3}) in rat neonatal ventricular cardiomyocytes. Expression of the CaSR protein was observed by Western blot. The apoptotic ratio of rat neonatal ventricular cardiomyocytes was measured with flow cytometry and immunofluorescence techniques. A laser scan confocal microscope was used to detect the intracellular concentration of calcium ([Ca{sup 2+}]{sub i}) in rat neonatal ventricular cardiomyocytes using the acetoxymethyl ester of fluo-3 (fluo-3/(AM)) as a fluorescent dye. The results showed that GdCl{sub 3} increased the phosphorylation of extracellular signal-regulated protein kinase (ERK), c-Jun NH{sub 2}-terminal protein kinases (JNK), and p38. GdCl{sub 3} also activated caspase 9 and increased apoptosis in myocyte by increasing [Ca{sup 2+}]{sub i}. In conclusion, these results suggest that CaSR promotes cardiomyocyte apoptosis in rat neonatal ventricular cardiomyocytes through activation of mitogen-activated protein kinases and caspase 9 signaling pathways.

  2. Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology

    PubMed Central

    Krishnamoorthi, Shankarjee; Perotti, Luigi E.; Borgstrom, Nils P.; Ajijola, Olujimi A.; Frid, Anna; Ponnaluri, Aditya V.; Weiss, James N.; Qu, Zhilin; Klug, William S.; Ennis, Daniel B.; Garfinkel, Alan

    2014-01-01

    We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations. PMID:25493967

  3. Intramyocardial activation in early ventricular arrhythmias following coronary artery ligation.

    PubMed

    Kaplinsky, E; Ogawa, S; Kmetzo, J; Balke, C W; Dreifus, L S

    1980-01-01

    Subendocardial, subepicardial and intramyocardial activation in the ischemic zone was investigated in 20 anesthetized open chest dogs 0-30 minutes after the ligation of the left anterior descending coronary artery. Single and composite electrograms and lead 2 of the ECG were recorded. Coronary artery ligation produced marked delay, fragmentation, and reduction in amplitude in the electrical activity of the subepicardial and intramyocardial muscle layers. The activation remained synchronous in the subendocardial muscle layers. Extension of electrical activity in the ischemic subepicardium and intramyocardium beyond the T wave of the surface ECG preceded the onset of immediate ventricular arrhythmias (IVA) during the initial ten minute period after coronary artery ligation. However, a second surge of delayed ventricular arrhythmias (DVA), 10-30 minutes after ligation, was not associated with the appearance of diastolic electrical activity in any of the subepicardial or myocardial layers. It appears that subepicardial as well as intramyocardial reentry could play an important role in the genesis of the immediate ventricular arrhythmias (1-10 minutes after ligation). In contrast, no obvious reentrant activity as evidenced by delayed and fragmented electrical activity could be observed in the electrogram from any of the myocardial electrical activity could be observed in the electrogram from any of the myocardial layers with the appearance of delayed ventricular ectopic activity 10-30 minutes after ligation.

  4. Haemolysis after Amplatzer device closure of ventricular septal defect

    PubMed Central

    Mulvaney, S; Grech, V

    2007-01-01

    Over the last few years, a vast variety of devices have been developed to close various septal defects through the transcatheter route. Haemolysis has been documented after Amplatzer device closure of patent ductus arteriousus, atrial septal defect, and ventricular septal defect. We report one patient with self-limiting haemolysis after implantation of an Amplatzer perimembranous VSD device. PMID:22368673

  5. Novel Micropatterned Cardiac Cell Cultures with Realistic Ventricular Microstructure

    PubMed Central

    Badie, Nima; Bursac, Nenad

    2009-01-01

    Systematic studies of cardiac structure-function relationships to date have been hindered by the intrinsic complexity and variability of in vivo and ex vivo model systems. Thus, we set out to develop a reproducible cell culture system that can accurately replicate the realistic microstructure of native cardiac tissues. Using cell micropatterning techniques, we aligned cultured cardiomyocytes at micro- and macroscopic spatial scales to follow local directions of cardiac fibers in murine ventricular cross sections, as measured by high-resolution diffusion tensor magnetic resonance imaging. To elucidate the roles of ventricular tissue microstructure in macroscopic impulse conduction, we optically mapped membrane potentials in micropatterned cardiac cultures with realistic tissue boundaries and natural cell orientation, cardiac cultures with realistic tissue boundaries but random cell orientation, and standard isotropic monolayers. At 2 Hz pacing, both microscopic changes in cell orientation and ventricular tissue boundaries independently and synergistically increased the spatial dispersion of conduction velocity, but not the action potential duration. The realistic variations in intramural microstructure created unique spatial signatures in micro- and macroscopic impulse propagation within ventricular cross-section cultures. This novel in vitro model system is expected to help bridge the existing gap between experimental structure-function studies in standard cardiac monolayers and intact heart tissues. PMID:19413993

  6. Novel Role for Vinculin in Ventricular Myocyte Mechanics and Dysfunction

    PubMed Central

    Tangney, Jared R.; Chuang, Joyce S.; Janssen, Matthew S.; Krishnamurthy, Adarsh; Liao, Peter; Hoshijima, Masahiko; Wu, Xin; Meininger, Gerald A.; Muthuchamy, Mariappan; Zemljic-Harpf, Alice; Ross, Robert S.; Frank, Lawrence R.; McCulloch, Andrew D.; Omens, Jeffrey H.

    2013-01-01

    Vinculin (Vcl) plays a key structural role in ventricular myocytes that, when disrupted, can lead to contractile dysfunction and dilated cardiomyopathy. To investigate the role of Vcl in myocyte and myocardial function, cardiomyocyte-specific Vcl knockout mice (cVclKO) and littermate control wild-type mice were studied with transmission electron microscopy (TEM) and in vivo magnetic resonance imaging (MRI) tagging before the onset of global ventricular dysfunction. MRI revealed significantly decreased systolic strains transverse to the myofiber axis in vivo, but no changes along the muscle fibers or in fiber tension in papillary muscles from heterozygous global Vcl null mice. Myofilament lattice spacing from TEM was significantly greater in cVclKO versus wild-type hearts fixed in the unloaded state. AFM in Vcl heterozygous null mouse myocytes showed a significant decrease in membrane cortical stiffness. A multiscale computational model of ventricular mechanics incorporating cross-bridge geometry and lattice mechanics showed that increased transverse systolic stiffness due to increased lattice spacing may explain the systolic wall strains associated with Vcl deficiency, before the onset of ventricular dysfunction. Loss of cardiac myocyte Vcl may decrease systolic transverse strains in vivo by decreasing membrane cortical tension, which decreases transverse compression of the lattice thereby increasing interfilament spacing and stress transverse to the myofibers. PMID:23561539

  7. Sustained Ventricular Tachycardia and Cardiogenic Shock due to Scorpion Envenomation.

    PubMed

    Miranda, Carlos Henrique; Maio, Karina Tozatto; Moreira, Henrique Turin; Moraes, Marcos; Custodio, Viviane Imaculada do Carmo; Pazin-Filho, Antonio; Cupo, Palmira

    2014-01-01

    We describe a case of severe scorpion envenomation in an adult patient, with the presence of very rapid sustained ventricular tachycardia followed by cardiogenic shock, which was reversed by scorpion antivenom administration. Scorpion venom causes cardiac changes that can lead to an environment favoring arrhythmogenesis. PMID:24715906

  8. Absence of left ventricular hypertrophy in elite college basketball players.

    PubMed

    Wolfe, L A; Martin, R P; Seip, R L

    1985-09-01

    Left ventricular dimensions of 11 successful male college basketball players engaged in pre-season conditioning (mean age, 20.3 years) and 13 tall healthy male controls (mean age, 21.6 years) were studied by echocardiography. Left ventricular internal dimension (LVIDd, mm), posterior wall thickness (PWT, mm), septal thickness (ST, mm), and calculated left ventricular mass (LV mass, g) in the athletes were within or only slightly in excess of echocardiographic normal limits and mean values were not significantly different from the control group. LVIDd (mm/m2 body surface area) was significantly lower in the athletes. However, five guard-type players displayed significantly greater mean values for PWT and LV mass compared to six taller forwards/centers with linear body builds. It was concluded that left ventricular hypertrophy is not a common characteristic of college basketball players. It was hypothesized that cardiac dimensions of young men may vary independently of gross body size in relation to somatotype or other anthropometric variables.

  9. Ventricular Septal Perforation Caused by the Strut of a Mitral Valve Bioprosthesis.

    PubMed

    Dagnegård, Hanna H; Ugander, Martin; Liska, Jan; Källner, Göran G

    2016-03-01

    Ventricular rupture is a well-known complication of mitral valve replacement. We report a rare complication in which the strut of a recently implanted mitral bioprosthesis eroded through the ventricular septum. We present the strategy of the reoperation in which the sutures holding the repair patch were also used to support the new prosthesis. In addition to ventricular rupture and obstruction of the left ventricular outflow tract by a mitral bioprosthesis, the risk of iatrogenic ventricular septal defect (VSD) should be considered when choosing, sizing, and implanting a mitral bioprosthesis. PMID:26897197

  10. An ECG changed the life of a young boy: a case of arrhythmogenic right ventricular dysplasia

    PubMed Central

    Altun, Ibrahim; Akin, Fatih; Sahin, Cem; Beydilli, Halil

    2014-01-01

    Arrhythmogenic right ventricular dysplasia (ARVD) is a progressive condition with the right ventricular myocardium being replaced by fibrofatty tissue. It is a hereditary disorder mostly caused by desmosome gene mutations. The prevalence of arrhythmogenic right ventricular cardiomyopathy is about 1/1000–5000. Clinical presentation is usually related to ventricular tachycardias, syncope, presyncope or ventricular fibrillation leading to cardiac arrest, mostly in young people and athletes. We report a case of a 17-year-old boy from Turkey, who was referred to our cardiology department for an ECG, required of him prior to joining a football team. PMID:25344388

  11. Duration of diastole versus cycle length as correlates of left ventricular ejection time

    NASA Technical Reports Server (NTRS)

    Weisdorf, D.; Spodick, D. H.

    1976-01-01

    Studies were done on 82 normal subjects to evaluate cycle length vs duration of diastole as determinants of left ventricular ejection time. Cycle length and its reciprocal, heart rate, had the highest correlation with left ventricular ejection time. Removal of the self-correlation of left ventricular ejection time within cycle length reduces the correlation so that, of all intervals, duration of diastole had the highest correlation as a determinant of left ventricular ejection time. Cycle length and heart rate remain valuable as spuriously close but not misleading correlates for predicting or correcting left ventricular ejection time.

  12. A case of hybrid closure of a muscular ventricular septal defect: anatomical complexity and surgical management.

    PubMed

    Karimi, Mohsen; Hulsebus, Elise; Murdison, Kenneth; Wiles, Henry

    2012-06-01

    Complex muscular ventricular septal defect poses difficult surgical management and is associated with high morbidity and mortality despite advancements in surgical therapy. Device closure of muscular ventricular septal defect has been encouraging and has been used in hybrid approach at a few centres. However, device closure has some limitations in patients with complex muscular ventricular septal defect. We report a case of perventricular device closure of a complex muscular ventricular septal defect in a beating heart with entrapped right ventricular disc and its surgical management.

  13. J point elevation as a predictor of premature ventricular beats.

    PubMed

    Matoshvili, Z; Petriashvili, Sh; Archvadze, A; Azaladze, I

    2014-01-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. 36 patients were included in this observation. There are 36 patients (19-68 years old) with early repolarization ECG patterns. All this 36 patients were divided into two groups according to their level of J point elevation. First group consisted of 12 patients with J point elevation ≥0,15 mV; second group - of 24 patients with J point elevation <0,15 mV. We make 24 h ECG holter monitoring all this patients to evaluate absolute number of premature ventricular beat during 24 h. Before and during this monitoring patients don't take any antyarrhythmic drugs. In the first group (J point elevation ≥0,15 mV) sum of premature ventricular beats were 27432, in the second group (J point elevation <0,15 mV) sum of premature ventricular beats were 31 896. The results of this observational study shows that there is 1,72 fold higher number of premature ventricular beats in first group. So, J point elevation equal or more then 0,15 mV, is more arrhythmogenic and induces premature ventricular beats. This is principally new and very important result.

  14. Normal rate of ventricular emptying in valvular aortic stenosis.

    PubMed Central

    Lederman, S M; Gash, A K; Bove, A A; Spann, J F

    1981-01-01

    The delayed upstroke of the arterial pulse in valvular aortic stenosis has been attributed, in part, to prolonged left ventricular emptying. Left ventricular emptying rate, however, has not been measured in aortic stenosis. We assessed the rate of left ventricular emptying by computer analysis of biplane cineangiograms in seven normal subjects, six patients with mild to moderate aortic stenosis, and 12 patients with severe aortic stenosis. As an indicator of delayed arterial pulse rise, T time index (time to half maximum aortic pressure corrected for heart rate) was measured in each group. T time index averaged 0.07 +/- 0.01 units in normal subjects, 0.14 +/- 0.04 units in the patients with mild to moderate aortic stenosis, and 0.13 +/- 0.05 units in those with severe aortic stenosis. Patients with mild to moderate and severe aortic stenosis differed significantly from normal subjects. Relative emptying rates were defined as the percentage of initial systolic volume ejected divided by the percentage of systole elapsed. These relative emptying rates were determined during the first, second, and third thirds of systole in all three groups. No significant decrease in the relative rate of left ventricular emptying was noted when each group of patients with aortic stenosis was compared with the normal subjects. Neither was there slowing in the actual rate of ejection of blood in ml per second throughout systole. We conclude that the rate of ventricular emptying is normal in aortic stenosis and does not explain the arterial pulse delay in this disease. PMID:7295438

  15. Molsidomine prevents post-ischaemic ventricular fibrillation in dogs.

    PubMed Central

    Cano, J. P.; Guillen, J. C.; Jouve, R.; Langlet, F.; Puddu, P. E.; Rolland, P. H.; Serradimigni, A.

    1986-01-01

    Forty anaesthetized dogs were subjected to left circumflex coronary artery ligation followed by reperfusion. Molsidomine was randomly administered to 20 dogs (50 micrograms kg-1 as an i.v. bolus - 15 min prior to coronary occlusion - followed by an infusion of 0.05 micrograms kg-1 min-1. Standard electrocardiographic leads 2 and 3 were continuously recorded to measure ST segment and delta R% changes and to document both the number of ventricular premature beats and the onset of ventricular fibrillation; aortic pressure and cardiac output were measured; thromboxane B2 plasma levels, platelet aggregation produced by ADP, and molsidomine plasma levels were determined before and at 10, 30 and 75 min after the start of the drug protocol. Molsidomine protected the treated animals from early (10 min) post-ischaemic ventricular fibrillation (0 of 20 vs 6 of 20, P = 0.0202), reduced the incidence of overall post-occlusion ventricular fibrillation (3 of 20 vs 10 of 20, P = 0.0407) and improved the total survival rate (P = 0.0067). In molsidomine treated dogs: mean aortic pressure and the rate-pressure product were lowered 10 min after the start of the drug; immediate post-occlusion (3 min) ST segment changes (0.82 +/- 0.52 vs 1.52 +/- 0.78 mV, P less than 0.025) and delta R% changes (37 +/- 50 vs 90 +/- 84%, P less than 0.025) were less marked; the number of ventricular premature beats was lowered and finally, a progressive decline of platelet aggregation produced by ADP was achieved after 75 min of drug infusion. These results were obtained in the presence of mean plasma levels of molsidomine ranging from 20 to 28 ng ml-1. The time-action curve of the antifibrillatory effect of molsidomine parallels those at the level of post-ischaemic electrocardiographic changes. Images Figure 2 PMID:3755634

  16. Clobutinol delays ventricular repolarization in the guinea pig heart: comparison with cardiac effects of HERG K+ channel inhibitor E-4031.

    PubMed

    Takahara, Akira; Sasaki, Rieko; Nakamura, Mariko; Sendo, Akiko; Sakurai, Yukiko; Namekata, Iyuki; Tanaka, Hikaru

    2009-12-01

    Clobutinol has been clinically reported to induce long QT syndrome. To clarify its cardiac electrophysiological properties, we compared effects of clobutinol on the isolated myocardium and anesthetized guinea pig heart with those of a hERG K channel blocker, E-4031. In isolated guinea pig ventricular tissues, clobutinol (3 microM) as well as E-4031 (10-100 nM) prolonged the action potential duration without affecting maximum upstroke velocity, but no further prolongation was observed after application of 30 microM clobutinol. In anesthetized closed-chest guinea pigs, clobutinol (1 and 10 mg/kg, intravenously) and E-4031 (0.01 and 1 mg/kg, intravenously) prolonged the QT interval and duration of the monophasic action potential (MAP) in a dose-dependent manner and at the same time increased the beat-to-beat variability of the MAP duration and reversed use-dependent prolongation of the MAP duration and triangulation of the MAP configuration. These results suggest that clobutinol delayed the ventricular repolarization and increased the proarrhythmic parameters linked to the hERG K channel inhibitor-induced torsade de pointes arrhythmias.

  17. Clobutinol delays ventricular repolarization in the guinea pig heart: comparison with cardiac effects of HERG K+ channel inhibitor E-4031.

    PubMed

    Takahara, Akira; Sasaki, Rieko; Nakamura, Mariko; Sendo, Akiko; Sakurai, Yukiko; Namekata, Iyuki; Tanaka, Hikaru

    2009-12-01

    Clobutinol has been clinically reported to induce long QT syndrome. To clarify its cardiac electrophysiological properties, we compared effects of clobutinol on the isolated myocardium and anesthetized guinea pig heart with those of a hERG K channel blocker, E-4031. In isolated guinea pig ventricular tissues, clobutinol (3 microM) as well as E-4031 (10-100 nM) prolonged the action potential duration without affecting maximum upstroke velocity, but no further prolongation was observed after application of 30 microM clobutinol. In anesthetized closed-chest guinea pigs, clobutinol (1 and 10 mg/kg, intravenously) and E-4031 (0.01 and 1 mg/kg, intravenously) prolonged the QT interval and duration of the monophasic action potential (MAP) in a dose-dependent manner and at the same time increased the beat-to-beat variability of the MAP duration and reversed use-dependent prolongation of the MAP duration and triangulation of the MAP configuration. These results suggest that clobutinol delayed the ventricular repolarization and increased the proarrhythmic parameters linked to the hERG K channel inhibitor-induced torsade de pointes arrhythmias. PMID:19770670

  18. Evaluation of left ventricular scar identification from contrast enhanced magnetic resonance imaging for guidance of ventricular catheter ablation therapy

    NASA Astrophysics Data System (ADS)

    Rettmann, M. E.; Lehmann, H. I.; Johnson, S. B.; Packer, D. L.

    2016-03-01

    Patients with ventricular arrhythmias typically exhibit myocardial scarring, which is believed to be an important anatomic substrate for reentrant circuits, thereby making these regions a key target in catheter ablation therapy. In ablation therapy, a catheter is guided into the left ventricle and radiofrequency energy is delivered into the tissue to interrupt arrhythmic electrical pathways. Low bipolar voltage regions are typically localized during the procedure through point-by-point construction of an electroanatomic map by sampling the endocardial surface with the ablation catheter and are used as a surrogate for myocardial scar. This process is time consuming, requires significant skill, and has the potential to miss low voltage sites. This has led to efforts to quantify myocardial scar preoperatively using delayed, contrast-enhanced MRI. In this paper, we evaluate the utility of left ventricular scar identification from delayed contrast enhanced magnetic resonance imaging for guidance of catheter ablation of ventricular arrhythmias. Myocardial infarcts were created in three canines followed by a delayed, contrast enhanced MRI scan and electroanatomic mapping. The left ventricle and myocardial scar is segmented from preoperative MRI images and sampled points from the procedural electroanatomical map are registered to the segmented endocardial surface. Sampled points with low bipolar voltage points visually align with the segmented scar regions. This work demonstrates the potential utility of using preoperative delayed, enhanced MRI to identify myocardial scarring for guidance of ventricular catheter ablation therapy.

  19. Shoshin beriberi with vasospastic angina pectoris possible mechanism of mid-ventricular obstruction: possible mechanism of mid-ventricular obstruction.

    PubMed

    Ito, Masahiro; Tanabe, Yasuhiko; Suzuki, Kaoru; Kumakura, Makoto; Aizawa, Yoshifusa

    2002-11-01

    A 73-year-old heavy drinker was admitted to hospital in a state of shock. He had been suffering from frequent angina at rest, causing him to drink more heavily in an effort to overcome his anginal chest pain. He had been drinking hard each day and had not eaten for 4 weeks. His hemodynamic state on admission showed high-output heart failure. Echocardiography revealed hyperkinesis of the left ventricle and mid-ventricular obstruction with peak intraventricular gradients of 30 mmHg. Although no improvement was seen despite administering the maximal dose in catecholamine therapy, his condition improved rapidly after vitamin B(1) was administered. Cardiac catheterization revealed mid-ventricular obstruction with an apical aneurysm. Coronary artery spasm was induced by injecting acetylcholine in the distal site of the left anterior descending artery, which perfused the area of the apical aneurysm. In the present case, both left ventricular hyperkinesis caused by shoshin beriberi and apical myocardial infarction caused by frequent coronary spasms produced mid-ventricular obstruction with an apical aneurysm.

  20. Elucidation of the spatial ventricular gradient and its link with dispersion of repolarization.

    PubMed

    Draisma, Harmen H M; Schalij, Martin J; van der Wall, Ernst E; Swenne, Cees A

    2006-09-01

    The ventricular gradient, a notion conceived by Wilson et al during the 1930s, has contributed considerably to a better understanding of the ECG manifestations of the cardiac repolarization process. The power of the ventricular gradient is its ability to assess the primary factors that contribute to the T wave (i.e., heterogeneity of action potential morphology throughout the ventricles) in the presence of secondary factors contributing to the T wave (i.e., heterogeneity in ventricular depolarization instants). Where T-wave morphology is an ECG expression of heterogeneity of the repolarization, the ventricular gradient discriminates between primary or secondary causes of such heterogeneity. Besides the spatial ventricular gradient (Burger's three-dimensional elaboration of Wilson's two-dimensional concept), body surface mapping of local components of the ventricular gradient has emerged as a technique for assessing local ventricular action potential duration heterogeneity. The latter is believed to contribute to localization of arrhythmogenic areas in the heart. The spatial ventricular gradient, which can be computed on the basis of a regular routine ECG and does not require body surface mapping, aims to assess the overall heterogeneity of ventricular action potential morphology. This review addresses the nature and diagnostic potential of the spatial ventricular gradient. The main focus is the role of the spatial ventricular gradient in ECG assessment of dispersion of repolarization, a key factor in arrhythmogeneity.

  1. Postoperative thallium-201 myocardial images. Evidence of regression of right ventricular hypertrophy in man.

    PubMed Central

    Yamazaki, H; Tsugu, T; Handa, S; Takagi, Y; Ohsuzu, F; Kondo, M; Kubo, A; Inoue, T; Nakamura, Y

    1982-01-01

    Thallium-201 myocardial scintigraphic studies were performed on 24 patients with chronic right ventricular overload before and after surgical correction of haemodynamic overload. The ages of the patients ranged from 20 to 65 years (mean 39 years) at operation. The degree of right ventricular visualisation remained essentially unchanged in an early postoperative study (four to 60 days), though a decrease in right ventricular cavity size was noted in patients with right ventricular volume overload. On later follow-up (18 to 36 months), thallium uptake in the right ventricle was definitely less than before operation in all 13 patients studied at this time. Because thallium-201 radioactivity reflects myocardial blood flow and mass, our study indicates that right ventricular hypertrophy is largely reversible. Thus, thallium-201 myocardial scintigraphy can be used to assess non-invasively regression of right ventricular hypertrophy in patients with right ventricular overload. Images PMID:6215051

  2. Left atrial appendage dysfunction in a patient with premature ventricular contractions - a risk factor for stroke?

    PubMed

    Patel, Sandeep M; Ackerman, Michael J; Asirvatham, Samuel J

    2013-01-01

    A 16-year-old female with ventricular dysfunction and frequent ventricular arrhythmia presented with a cardioembolic stroke. Prior electrophysiology study and ablation was performed for ventricular tachycardia (VT). For remaining ventricular ectopy, the patient was maintained on carvedilol and mexiletine. After one year on this regimen, she presented with an acute stroke. Transesophageal echocardiography revealed no evidence of an intracardiac or ventricular thrombus but demonstrated markedly decreased left atrial appendage (LAA) flow velocity worsened during frequent premature ventricular contractions (PVC). In the absence of atrial fibrillation (AF), the LAA dysfunction was considered secondary to the frequent PVCs and was thought to be the underlying cause for the stroke. We present this case to highlight a potential under recognized association between LAA dysfunction and ventricular arrhythmia, similar to that observed with atrioventricular dyssynchronous pacing. PMID:24086095

  3. Social isolation

    PubMed Central

    Cacioppo, John T.; Hawkley, Louise C.; Norman, Greg J.; Berntson, Gary G.

    2011-01-01

    Social species, by definition, form organizations that extend beyond the individual. These structures evolved hand in hand with behavioral, neural, hormonal, cellular, and genetic mechanisms to support them because the consequent social behaviors helped these organisms survive, reproduce, and care for offspring sufficiently long that they too reproduced. Social isolation represents a lens through which to investigate these behavioral, neural, hormonal, cellular, and genetic mechanisms. Evidence from human and nonhuman animal studies indicates that isolation heightens sensitivity to social threats (predator evasion) and motivates the renewal of social connections. The effects of perceived isolation in humans share much in common with the effects of experimental manipulations of isolation in nonhuman social species: increased tonic sympathetic tonus and HPA activation, and decreased inflammatory control, immunity, sleep salubrity, and expression of genes regulating glucocorticoid responses. Together, these effects contribute to higher rates of morbidity and mortality in older adults. PMID:21651565

  4. The effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline-induced right ventricular failure

    PubMed Central

    Bae, Hyun Kyung; Lee, Hyeryon; Kim, Kwan Chang

    2016-01-01

    Purpose Pulmonary arterial hypertension (PAH) leads to right ventricular failure (RVF) as well as an increase in pulmonary vascular resistance. Our purpose was to study the effect of sildenafil on right ventricular remodeling in a rat model of monocrotaline (MCT)-induced RVF. Methods The rats were distributed randomly into 3 groups. The control (C) group, the monocrotaline (M) group (MCT 60 mg/kg) and the sildenafil (S) group (MCT 60 mg/kg+ sildenafil 30 mg/kg/day for 28 days). Masson Trichrome staining was used for heart tissues. Western blot analysis and immunohistochemical staining were performed. Results The mean right ventricular pressure (RVP) was significantly lower in the S group at weeks 1, 2, and 4. The number of intra-acinar arteries and the medial wall thickness of the pulmonary arterioles significantly lessened in the S group at week 4. The collagen content also decreased in heart tissues in the S group at week 4. Protein expression levels of B-cell lymphoma-2 (Bcl-2)-associated X, caspase-3, Bcl-2, interleukin (IL)-6, matrix metalloproteinase (MMP)-2, endothelial nitric oxide synthase (eNOS), endothelin (ET)-1 and ET receptor A (ERA) in lung tissues greatly decreased in the S group at week 4 according to immunohistochemical staining. According to Western blotting, protein expression levels of troponin I, brain natriuretic peptide, caspase-3, Bcl-2, tumor necrosis factor-α, IL-6, MMP-2, eNOS, ET-1, and ERA in heart tissues greatly diminished in the S group at week 4. Conclusion Sildenafil alleviated right ventricular hypertrophy and mean RVP. These data suggest that sildenafil improves right ventricular function. PMID:27462355

  5. Increased rat cardiac angiotensin converting enzyme activity and mRNA expression in pressure overload left ventricular hypertrophy. Effects on coronary resistance, contractility, and relaxation.

    PubMed Central

    Schunkert, H; Dzau, V J; Tang, S S; Hirsch, A T; Apstein, C S; Lorell, B H

    1990-01-01

    We compared the activity and physiologic effects of cardiac angiotensin converting enzyme (ACE) using isovolumic hearts from male Wistar rats with left ventricular hypertrophy due to chronic experimental aortic stenosis and from control rats. In response to the infusion of 3.5 X 10(-8) M angiotensin I in the isolated buffer perfused beating hearts, the intracardiac fractional conversion to angiotensin II was higher in the hypertrophied hearts compared with the controls (17.3 +/- 4.1% vs 6.8 +/- 1.3%, P less than 0.01). ACE activity was also significantly increased in the free wall, septum, and apex of the hypertrophied left ventricle, whereas ACE activity from the nonhypertrophied right ventricle of the aortic stenosis rats was not different from that of the control rats. Northern blot analyses of poly(A)+ purified RNA demonstrated the expression of ACE mRNA, which was increased fourfold in left ventricular tissue obtained from the hearts with left ventricular hypertrophy compared with the controls. In both groups, the intracardiac conversion of angiotensin I to angiotensin II caused a comparable dose-dependent increase in coronary resistance. In the control hearts, angiotensin II activation had no significant effect on systolic or diastolic function; however, it was associated with a dose-dependent depression of left ventricular diastolic relaxation in the hypertrophied hearts. These novel observations suggest that cardiac ACE is induced in hearts with left ventricular hypertrophy, and that the resultant intracardiac activation of angiotensin II may have differential effects on myocardial relaxation in hypertrophied hearts relative to controls. Images PMID:2174912

  6. Adult rodent neurogenic regions: the ventricular subependyma contains neural stem cells, but the dentate gyrus contains restricted progenitors.

    PubMed

    Seaberg, Raewyn M; van der Kooy, Derek

    2002-03-01

    Neurogenesis persists in two adult brain regions: the ventricular subependyma and the subgranular cell layer in the hippocampal dentate gyrus (DG). Previous work in many laboratories has shown explicitly that multipotential, self-renewing stem cells in the subependyma are the source of newly generated migrating neurons that traverse the rostral migratory stream and incorporate into the olfactory bulb as interneurons. These stem cells have been specifically isolated from the subependyma, and their properties of self-renewal and multipotentiality have been demonstrated in vitro. In contrast, it is a widely held assumption that the "hippocampal" stem cells that can be isolated in vitro from adult hippocampus reside in the neurogenic subgranular layer and represent the source of new granule cell neurons, but this has never been tested directly. Primary cell isolates derived from the precise microdissection of adult rodent neurogenic regions were compared using two very different commonly used culture methods: a clonal colony-forming (neurosphere) assay and a monolayer culture system. Importantly, both of these culture methods generated the same conclusion: stem cells can be isolated from hippocampus-adjacent regions of subependyma, but the adult DG proper does not contain a population of resident neural stem cells. Indeed, although the lateral ventricle and other ventricular subependymal regions directly adjacent to the hippocampus contain neural stem cells that exhibit long-term self-renewal and multipotentiality, separate neuronal and glial progenitors with limited self-renewal capacity are present in the adult DG, suggesting that neuron-specific progenitors and not multipotential stem cells are the source of newly generated DG neurons throughout adulthood.

  7. Encircling endocardial ventriculotomy for refractory ischemic ventricular tachycardia. II. Effects on regional myocardial blood flow.

    PubMed

    Ungerleider, R M; Holman, W L; Stanley, T E; Lofland, G K; Williams, J M; Smith, P K; Quick, G; Cox, J L

    1982-06-01

    Previous experimental studies of the encircling endocardial ventriculotomy (EEV) have shown a significant alteration of normal local electrical activity within the encompassed region. Although this procedure may result in isolation of ventricular arrhythmias, the data are more suggestive of a less specific effect on regional myocardial blood flow. This study examines the effect of EEV on local myocardial blood flow using the radioactive tracer microsphere technique in 10 dogs. Flows were determined before and after an EEV with the animals on cardiopulmonary bypass at controlled perfusion pressures, temperatures, and heart rates. Blood flow was studied at subepicardial and subendocardial levels inside, outside, and bordering the EEV. Prior to performance of the EEV, subepicardial blood flow in the left ventricular myocardium ranged from 0.81 +/- 0.07 to 0.89 +/- 0.08 ml/gm/min. Subendocardial flows ranged from 0.80 +/- 0.07 to 0.91 +/- 0.09 ml/gm/min. There was no significant difference between any of the flows across each respective layer of myocardium. Following the EEV procedure, blood flow to the subendocardium within the EEV fell to 0.33 +/- 0.07 ml/gm/min, while flow to the subendocardium of the normal regions of the same hearts actually increased to 1.21 +/- 0.23 ml/gm/min. Similar changes occurred at subepicardial levels, with flow at the center of the EEV falling to 0.66 +/- 0.10 ml/gm/min despite a tendency for normal subepicardial flow to increase to 1.78 +/- 0.24 ml/gm/min. Superimposed ischemia to the EEV-encompassed myocardium, created by occlusion of the distal left anterior descending coronary artery (LAD), accentuated this abnormality by demonstrating that the region continues to receive some flow from epicardially based coronary vessels. The data from this study show that the EEV decreased regional blood flow to the encompassed myocardium and suggests that myocardial ischemia may be responsible for ablation of the delicate re-entrant mechanisms

  8. Altered Na/Ca exchange distribution in ventricular myocytes from failing hearts

    PubMed Central

    Gadeberg, Hanne C.; Bryant, Simon M.; James, Andrew F.

    2015-01-01

    In mammalian cardiac ventricular myocytes, Ca efflux via Na/Ca exchange (NCX) occurs predominantly at T tubules. Heart failure is associated with disrupted t-tubular structure, but its effect on t-tubular function is less clear. We therefore investigated t-tubular NCX activity in ventricular myocytes isolated from rat hearts ∼18 wk after coronary artery ligation (CAL) or corresponding sham operation (Sham). NCX current (INCX) and l-type Ca current (ICa) were recorded using the whole cell, voltage-clamp technique in intact and detubulated (DT) myocytes; intracellular free Ca concentration ([Ca]i) was monitored simultaneously using fluo-4. INCX was activated and measured during application of caffeine to release Ca from sarcoplasmic reticulum (SR). Whole cell INCX was not significantly different in Sham and CAL myocytes and occurred predominantly in the T tubules in Sham myocytes. CAL was associated with redistribution of INCX and ICa away from the T tubules to the cell surface and an increase in t-tubular INCX/ICa density from 0.12 in Sham to 0.30 in CAL myocytes. The decrease in t-tubular INCX in CAL myocytes was accompanied by an increase in the fraction of Ca sequestered by SR. However, SR Ca content was not significantly different in Sham, Sham DT, and CAL myocytes but was significantly increased by DT of CAL myocytes. In Sham myocytes, there was hysteresis between INCX and [Ca]i, which was absent in DT Sham but present in CAL and DT CAL myocytes. These data suggest altered distribution of NCX in CAL myocytes. PMID:26566728

  9. Impact of Nonischemic Scar Features on Local Ventricular Electrograms and Scar-Related Ventricular Tachycardia Circuits in Patients with Nonischemic Cardiomyopathy

    PubMed Central

    Sasaki, Takeshi; Miller, Christopher F.; Hansford, Rozann; Zipunnikov, Vadim; Zviman, Menekhem M.; Marine, Joseph E.; Spragg, David; Cheng, Alan; Tandri, Harikrishna; Sinha, Sunil; Kolandaivelu, Aravindan; Zimmerman, Stefan L.; Bluemke, David A.; Tomaselli, Gordon F.; Berger, Ronald D.; Halperin, Henry R.; Calkins, Hugh; Nazarian, Saman

    2013-01-01

    Background The association of local electrogram features with scar morphology and distribution in nonischemic cardiomyopathy (NICM) has not been investigated. We aimed to quantify the association of scar on late-gadolinium enhanced cardiac magnetic resonance (LGE-CMR) with local electrograms and ventricular tachycardia (VT) circuit sites in patients with NICM. Methods and Results Fifteen patients with NICM underwent LGE-CMR before VT ablation. The transmural extent and intramural types (endocardial, mid-wall, epicardial, patchy, transmural) of scar were measured in LGE-CMR short axis planes. Electro-anatomic map (EAM) points were registered to LGE-CMR images. Myocardial wall thickness, scar transmurality, and intramural scar types were independently associated with electrogram amplitude, duration, and deflections in linear mixed effects multivariable models, clustered by patient. Fractionated and isolated potentials were more likely to be observed in regions with higher scar transmurality (P<0.0001 by ANOVA) and in regions with patchy scar (versus endocardial, mid wall, epicardial scar, P<0.05 by ANOVA). Most VT circuit sites were located in scar with >25% scar transmurality. Conclusions Electrogram features are associated with scar morphology and distribution in patients with NICM. Prior knowledge of electrogram image associations may optimize procedural strategies including the decision to obtain epicardial access. PMID:24235267

  10. [Experimental principles for preserving annulo-ventricular integrity of the mitral valve].

    PubMed

    Gams, E; Schad, H; Heimisch, W

    1996-06-01

    Despite numerous improvement in cardiac surgery the results in mitral valve replacement are still not satisfactory, since impaired left ventricular function continues to be a problem during the postoperative course. In order to investigate the effect of mitral valve replacement on left ventricular function canine experiments were performed: During extracorporeal circulation bileaflet mitral valve prostheses were implanted preserving the ventriculo-annular continuity. Flexible wires were slung around the chordae of the subvalvular mitral apparatus and brought to the outside through the left ventricular wall. Left ventricular diameters were measured by sonomicrometry, left ventricular stroke volume, left ventricular enddiastolic volume and ejection fraction by dye dilution technique as well as left ventricular and aortic pressure by catheter tip manometers. After finishing cardiopulmonary bypass control values were registered and different preload values achieved by volume loading with blood transfusions to left ventricular enddiastolic pressures of 12 mm Hg. Subsequently under normovolumic conditions the chordae tendineae of the anterior and posterior papillary muscles of the mitral valve were cut from the outside, while the heart was beating, by application of electrocautery on the steel wires. Following severance of the ventriculo-annular continuity of the mitral valve again function curves of left ventricular hemodynamics were made during volume transfusions. When the chordae had been divided the left ventricular enddiastolic diameter increased by 10% in the major axis, while in the minor axis no significant changes occurred. The systolic shortening was impaired substantially by reduction of 43% during the ejection phase when the subvalvular mitral apparatus had been severed. Left ventricular enddiastolic volume was increased by 18% at any preload level, while left ventricular ejection fraction was reduced by 16%. Consequently left ventricular stroke volume was

  11. Right Ventricular Apical Flattening as an Echocardiographic Screening Tool for Right Ventricular Enlargement.

    PubMed

    Buddhe, Sujatha; Ferguson, Mark; Arya, Bhawna; Soriano, Brian D

    2016-03-01

    Right ventricular dilation is a common complication after tetralogy of Fallot (TOF) repair. Traditional echocardiographic assessments are imprecise due to the RV's location and complex geometry. We propose a novel echocardiographic measurement: RV apical flattening (RVAF) as a screening tool to help identify subjects with severe RV dilation. Patients with repaired TOF who had both echocardiograms and CMR's within 6-month interval at our institution were included in the study. The RVAF was measured in the four-chamber echocardiographic view as the minor length of RV cavity at the level of RV apical endocardium. Subjects were divided into two groups (group I: RVEDVi ≥ 150 ml/m(2) and group II; RVEDVi < 150 ml/m(2)). Echocardiogram and CMR data were compared between groups. A total of 75 subjects were included in the study. Mean age was 12.8 ± 3.6 years. Group I had 36 subjects, and group II had 39 subjects. The mean RVAF was significantly higher in group I (2.7 ± 0.5 cm) compared with group II (1.7 ± 0.4 cm; p < 0.001). There was significant correlation between RVAF and RVEDVi (r = 0.81; p < 0.001). By ROC analysis, an RVAF cutoff value of 2.0 cm had 94 % sensitivity and 77 % specificity in identifying severe RV dilation (area under the curve 0.95). RVAF is a simple and effective echocardiographic screening tool to help identify severe RV dilation. In conjunction with other 2D echocardiographic parameters, this technique would help further refine echocardiography-guided patient selection for timing of CMR and pulmonary valve replacement.

  12. Three-wall segment (TriSeg) model describing mechanics and hemodynamics of ventricular interaction.

    PubMed

    Lumens, Joost; Delhaas, Tammo; Kirn, Borut; Arts, Theo

    2009-11-01

    A mathematical model (TriSeg model) of ventricular mechanics incorporating mechanical interaction of the left and right ventricular free walls and the interventricular septum is presented. Global left and right ventricular pump mechanics were related to representative myofiber mechanics in the three ventricular walls, satisfying the principle of conservation of energy. The walls were mechanically coupled satisfying tensile force equilibrium in the junction. Wall sizes and masses were rendered by adaptation to normalize mechanical myofiber load to physiological standard levels. The TriSeg model was implemented in the previously published lumped closed-loop CircAdapt model of heart and circulation. Simulation results of cardiac mechanics and hemodynamics during normal ventricular loading, acute pulmonary hypertension, and chronic pulmonary hypertension (including load adaptation) agreed with clinical data as obtained in healthy volunteers and pulmonary hypertension patients. In chronic pulmonary hypertension, the model predicted right ventricular free wall hypertrophy, increased systolic pulmonary flow acceleration, and increased right ventricular isovolumic contraction and relaxation times. Furthermore, septal curvature decreased linearly with its transmural pressure difference. In conclusion, the TriSeg model enables realistic simulation of ventricular mechanics including interaction between left and right ventricular pump mechanics, dynamics of septal geometry, and myofiber mechanics in the three ventricular walls.

  13. 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.

  14. Hemodynamic-impact-based prioritization of ventricular tachycardia alarms.

    PubMed

    Desai, Kalpit; Lexa, Michael; Matthews, Brett; Genc, Sahika

    2014-01-01

    Ventricular tachycardia (V-tach) is a very serious condition that occurs when the ventricles are driven at high rates. The abnormal excitation pathways make ventricular contraction less synchronous resulting in less effective filling and emptying of the left ventricles. However, almost half of the V-tach alarms declared through processing of patterns observed in electrocardiography are not clinically actionable. The focus of this study is to provide guidance on determining whether a technically-correct V-tach alarm is clinically-actionable by determining its "hemodynamic impact". A supervisory learning approach based on conditional inference trees to determine the hemodynamic impact of a V-tach alarm based on extracted features is described. According to preliminary results on a subset of Multiparameter intelligent monitoring in intensive care II (MIMIC-II) database, true positive rate of more than 90% can be achieved. PMID:25570734

  15. T Wave Alternans And Ventricular Tachyarrhythmia Risk Stratification: A Review

    PubMed Central

    Takagi, Masahiko; Yoshikawa, Junichi

    2003-01-01

    Sudden cardiac death (SCD) is one of the leading causes of mortality in industrialized countries. Thus, identifying patients at high risk of SCD is an important goal. T wave alternans (TWA) is a new method for identifying patients with lethal ventricular tachyarrhythmias, and is dependent on heart rate. The maximal predictive accuracy is achieved at heart rates between 100 and 120 bpm, so that TWA is usually measured during exercise, phamacological stress, or atrial pacing. It has been shown that TWA has high sensitivity and negative predictive value for predicting SCD after myocardial infarction and is also useful for predicting SCD in patients with nonischemic cardiomyopathy. Although the implantable cardioverter defibrillator (ICD) is now the primary therapy for preventing SCD, it is difficult to identify those patients who are susceptible to lethal ventricular tachyarrhythmias for primary prevention. In the prediction of SCD, TWA can be used as a screening test of appropriate patients for further electrophysiological examination and therapy. PMID:16943959

  16. Vortex Formation Time is Not an Index of Ventricular Function

    PubMed Central

    Vlachos, Pavlos P.; Little, William C.

    2015-01-01

    The diastolic intraventricular ring vortex formation and pinch-off process may provide clinically useful insights into diastolic function in health and disease. The vortex ring formation time (FT) concept, based on hydrodynamic experiments dealing with unconfined (large tank) flow, has attracted considerable attention and popularity. Dynamic conditions evolving within the very confined space of a filling, expansible ventricular chamber with relaxing and rebounding viscoelastic muscular boundaries, diverge from unconfined (large tank) flow and encompass rebounding walls’ suction and myocardial relaxation. Indeed, clinical/physiological findings seeking validation in vivo failed to support the notion that FT is an index of normal/abnormal diastolic ventricular function. Therefore, FT as originally proposed cannot and should not be utilized as such an index. Evidently, physiologically accurate models accounting for coupled hydrodynamic and (patho)physiological myocardial wall interactions with the intraventricular flow are still needed to enhance our understanding and yield diastolic function indices useful and reliable in the clinical setting. PMID:25609509

  17. Double outlet from chambers of left ventricular morphology.

    PubMed Central

    Coto, E O; Jimenez, M Q; Castaneda, A R; Rufilanchas, J J; Deverall, P B

    1979-01-01

    This series of 5 cases with double outlet of morphologically left ventricular chamber includes 4 found during a review of 1700 heart specimens (incidence 0.23%) and 1 found at operation and successfully corrected. Abnormal atrioventricular connection precluding total correction was present in the 4 anatomical cases. Clinical diagnosis may be difficult and it is suggested that axial cineangiography may make anatomical diagnosis easier. Absence of the infundibular septum and aortic laevoposition are frequent. As some cases can be surgically corrected, accurate information is required on the size of the right ventricle, the morphology and function of the atrioventricular valves, the presence, size, and position of the ventricular septal defect, and the degree and type of outflow tract obstruction. Images PMID:475930

  18. Novel Left Ventricular Assist System® II

    PubMed Central

    Liotta, Domingo

    2004-01-01

    The pump's outflow connector of the Novel Left Ventricular Assist System® I (Novel LVAS® I) has been redesigned to be sutured to the infrarenal abdominal aorta either as a procedure of choice (due to its simplicity) or as an alternative in the presence of an unhealthy descending thoracic aorta. The implantation of the Novel Left Ventricular Assist System® II (Novel LVAS® II) requires only a single passage of the pump's inflow connector through the diaphragm. Of still greater importance, the Novel LVAS II enables a considerably shorter (20- or 22-mm) Dacron vascular graft as the outflow connector to the abdominal infrarenal aorta. The electrocardiogram-synchronized Novel LVAS II possibly ensures the most effective approach to the perfusion of visceral organs and kidneys, while avoiding both excessive mechanical stress on the blood and anatomical and functional damage to the native left ventricle. PMID:15562850

  19. [The design of bionic left ventricular auxiliary pump].

    PubMed

    Jin, Henglin; Hu, Xiaobing; Du, Lei

    2015-01-01

    This paper reports a novel design of bionic left ventricular auxiliary pump, and the characteristic is that elastic diaphragm of pump driven by hydraulic, having smooth, reliable blood supply, can prevent blood clots, can use the flow sensor, pressure sensor detection showing the blood pressure and blood volume at the inlet and outlet of the pump. The pump can go with heart rate synchronization or asynchronous auxiliary by the R wave of human body's ECG. The design goal is realization of bionic throb. Through the animal experiment, the blood pressure waveforms are close to expectations, stable flow can stroke according to the set value, which prove that the pump can meet the requirement for heart disease patients for bionic left ventricular assistant.

  20. Angiocardiographic methods for determination of left ventricular geometry and volume

    NASA Technical Reports Server (NTRS)

    Sandler, H.; Dodge, H. T.

    1974-01-01

    Methods are described for calculating left ventricular (LV) dimensions and chamber volumes from radiographic films. The use of biplane films for the calculation of LV volume and volume change is based on the assumption of an ellipsoidal geometry. Calculation of LV volumes from biplane films usually overestimated known volumes in postmortem hearts regardless of the methods used for volume calculation. The reasons for this are probably best explained by the fact that a smooth-surface ellipse is used to represent the irregular cavity of the LV chamber. LV volume calculated from data in a single plane compared favorably and closely with volumes calculated from biplane films. A table of normal values of ventricular volume established by angiographic studies is presented.