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1

Cardiac Resynchronization Therapy Using a Dual Chamber Pacemaker in Patients with Severe Left Ventricular Dysfunction and a Left Bundle Branch Block  

PubMed Central

Through the use of a dual chamber (DDD) pacemaker, we achieved a cardiac resynchronization effect in a 51-year-old female patient who was transferred to our hospital from another hospital for an operation for three-vessel coronary artery disease. Her electrocardiogram showed a left bundle branch block (LBBB) and a prolonged QRS interval of 166 milliseconds. Severe left ventricle (LV) dysfunction was diagnosed via echocardiography. Coronary artery bypass grafting (CABG) was then performed. In order to accelerate left atrial activation and reduce the conduction defect, DDD pacing using right atrial and left and right ventricular pacing wires was initiated postoperatively. The cardiac output was measured immediately, and one and twelve hours after arrival in the intensive care unit. The cardiac output changed from 2.8, 2.4, and 3.6 L/min without pacing to 3.5, 3.4, and 3.5 L/min on initiation of pacing. The biventricular synchronization using DDD pacing was turned off 18 hours after surgery. She was transferred to a general ward with a cardiac output of 3.9 L/min. In patients with coronary artery disease, severe LV dysfunction, and LBBB, cardiac resynchronization therapy can be achieved through DDD pacing after CABG.

Jung, Jae Jun; Kim, In Sook; Jeong, Jae-Han; Jeong, Dong Seop

2013-01-01

2

[Inhospital thrombolism of right cardiac chambers].  

PubMed

Veins of lower extremities are classic sources of pulmonary artery thromboembolism (PATE). But one should not underestimate presence of thrombi in other potential sources - veins of small pelvis, superior vena cava, and chambers of the heart. We analyzed 652 case histories and autopsy data of patients in whom PATE had been revealed at pathological anatomical investigation and selected 157 cases in which right heart chambers were sources of emboli (right atrium in 83.5% and right ventricle - in 13.7% of cases). According to autopsy data average mass of the heart was 512.5+/-36.1 g. In most patients it exceeded norm. Thrombi in both right and left cardiac chambers were found in 52.3% of cases. Eighty three patients had history of myocardial infarction or were treated for MI during last hospitalization; 52.3% of patients had atrial fibrillation. After detailed study of all anamnestic, clinical, instrumental, and pathologic-anatomic data we selected 69 factors which according to contemporary views could facilitate formation of thrombus in the right cardiac chambers. Using these factors and method of logistic regression we created a mathematical model for assessment of probability of the presence of thrombi in right cardiac chambers. PMID:23953045

Vasil'tseva, O Ia; Vorozhtsova, I N; Karpov, R S

2013-01-01

3

Increased left atrial chamber stiffness in hypertrophic cardiomyopathy.  

PubMed Central

OBJECTIVE--To investigate left atrial chamber stiffness and its influence on left atrial and left ventricular functions in hypertrophic cardiomyopathy. DESIGN--Prospective study. SETTING--Department of internal medicine in a university teaching hospital. PATIENTS--Five control subjects, six patients with essential hypertension, and 11 patients with hypertrophic cardiomyopathy. INTERVENTIONS--Measurement of left atrial pressure by a tip micromanometer and of real-time left atrial volume from left atrial cineangiograms. MAIN OUTCOME MEASURE--Left atrial stiffness constant determined by fitting the ascending limb of the v loop of the left atrial pressure-volume relation to an exponential curve. RESULTS--The mean (SD) left atrial chamber stiffness constant was significantly larger in patients with hypertrophic cardiomyopathy than in controls (0.063 (0.018) v 0.041 (0.006), p < 0.05) and was correlated with left ventricular wall thickness (r = 0.560, p < 0.01). Left atrial reservoir volume (left atrial emptying volume before atrial contraction) was significantly smaller in patients with hypertrophic cardiomyopathy than in the controls (7.3 (2.1) v 12.5 (4.4) ml/m2, p < 0.01) and was inversely correlated with the left atrial chamber stiffness constant (r = -0.598, p < 0.01). The cardiac index was inversely correlated with the left atrial chamber stiffness constant (r = -0.542, p < 0.01). CONCLUSIONS--Left atrial chamber stiffness was increased in patients with hypertrophic cardiomyopathy and this affected the left atrial reservoir function. This may in turn have affected cardiac output.

Sanada, H; Shimizu, M; Sugihara, N; Shimizu, K; Ino, H; Takeda, R

1993-01-01

4

Linear vs. Quadratic Optimization Algorithms for Bias Correction of Left Ventricle Chamber Boundaries in Low Contrast Projection Ventriculograms Produced from Xray Cardiac Catheterization Procedure  

Microsoft Academic Search

Cardiac catheterization procedure produces ventriculograms which have very low contrast in the apical, anterior and inferior\\u000a zones of the left ventricle (LV). Pixel-based classifiers operating on these images produce boundaries which have systematic\\u000a positional and orientation bias and have a mean error of about 10.5 mm. Using the LV convex information, comprising of the\\u000a apex and the aortic valve plane,

Jasjit S. Suri; Robert M. Haralick; Florence H. Sheehan

1999-01-01

5

Two-chambered right ventricle: simulating two-chambered left ventricle.  

PubMed Central

Two cases are described of a most unusual variant of two-chambered right ventricle. In both the ventricular septal defect was between the distal chamber of the right ventricle and the left ventricle. However the extensive dividing 'septum' between proximal and distal parts of the right ventricle converted the latter, haemodynamically, into part of the left ventricle. In the first case the distal chamber supported the aorta in the left anterior position, the pulmonary artery arising from the proximal part of the right ventricle. In the second the pulmonary artery arose from the distal chamber and the aorta from the proximal chamber. Though in both the ventriculoarterial connection was double outlet right ventricle, functionally there was arterial concordance in case 1 and discordance in case 2. A further disconcerting feature was the resemblance of the distal right ventricular chamber to the rudimentary chamber of a univentricular heart of left ventricular type. Images

Beitzke, A; Anderson, R H; Wilkinson, J L; Shinebourne, E A

1979-01-01

6

Cardiac papillary fibroelastoma in left ventricular apex.  

PubMed

Papillary fibroelastoma (PF) is a rare benign heart tumor and represents less than 10% of primary cardiac tumors. It mainly affects the cardiac valves and is often discovered during open heart surgery or autopsy. We present a case of a patient who was detected with a left ventricular apex tumor during the evaluation of the transient ischemic attack. The patient underwent surgery, and subsequently, macroscopic and microscopic examination confirmed the diagnosis of PF. PMID:17868885

Company Campins, María Margarita; Antón, Ester; Enríquez, Fernando; Palmer, Juan; Serra, J Enrique; Bonnìn, Oriol

2007-08-06

7

13. Second floor, northeast chamber, south wall. Closet to left; ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Second floor, northeast chamber, south wall. Closet to left; bath to right. Stairs to attic are above shelves in the bath. - Conner Homestead, House, Epping Road (State Route 101), Exeter, Rockingham County, NH

8

The decrease of cardiac chamber volumes and output during positive-pressure ventilation.  

PubMed

Positive-pressure ventilation (PPV) is widely used for treatment of acute cardiorespiratory failure, occasionally at the expense of compromised cardiac function and arterial blood pressure. The explanation why has largely rested on interpretation of intracardiac pressure changes. We evaluated the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary artery were measured by CMR during PPV levels of 0, 10, and 20 cmH2O applied via a respirator and a face mask. All cardiac chamber volumes decreased in proportion to the level of PPV. Following 20-cmH2O PPV, the total diastolic and systolic cardiac volumes (±SE) decreased from 605 (±29) ml to 446 (±29) ml (P < 0.001) and from 265 (±17) ml to 212 (±16) ml (P < 0.001). Left ventricular stroke volume decreased by 27 (±4) ml/beat; heart rate increased by 7 (±2) beats/min; and CO decreased by 1.0 (±0.4) l/min (P < 0.001). From 0 to 20 cmH2O, right and left ventricular peak filling rates decreased by -146 (±32) and -187 (±64) ml/s (P < 0.05) but maximal emptying rates were unchanged. Cardiac filling and output decrease with increasing PPV in healthy volunteers. The decrease is seen even at low levels of PPV and should be taken into account when submitting patients to mechanical ventilation with positive pressures. The decrease in CO is fully explained by the Frank-Starling mechanism. PMID:23893161

Kyhl, Kasper; Ahtarovski, Kiril Aleksov; Iversen, Kasper; Thomsen, Carsten; Vejlstrup, Niels; Engstrøm, Thomas; Madsen, Per Lav

2013-07-26

9

Short atrioventricular delay dual-chamber pacing early after coronary artery bypass grafting in patients with poor left ventricular function  

Microsoft Academic Search

Objective: To investigate the effect of short atrioventricular (AV) delay dual-chamber pacing on mean arterial pressure (MAP) and stroke volume index (SVI) in patients with poor left ventricular (LV) function after cardiac surgery.Design: A prospective study.Setting: A university hospital, single-center study.Participants: The study group consisted of 20 patients aged 63 ± 9 years with a left ventricular ejection fraction (LVEF)

Andreas Liebold; Gabriele Rödig; Johannes Merk; Dietrich E. Birnbaum

1998-01-01

10

Use of real-time three-dimensional echocardiography to assess left ventricular systolic synchronization after dual-chamber pacing therapy  

PubMed Central

This study was designed to evaluate the left ventricular systolic synchronization in patients implanted with dual-chamber DDD mode cardiac pacemakers by real-time three-dimensional echocardiography (RT3DE). Twenty patients implanted with DDD mode cardiac pacemakers for 12 months and 20 healthy subjects underwent RT3DE. This method provided left ventricular end-diastolic volume (LEDV), left ventricular end-systolic volume (LESV), stroke volume (SV), left ventricular ejection fraction (LVEF), the mean value of the time to minimal systolic volume of the 16 left ventricular segments (Tmean), the standard deviation of Tmean (T-SD), the maximal difference of the time to minimal systolic volume of the 16 left ventricular segments (Tmax) and time-volume curves of the 16 left ventricular segments. Results showed that compared with the healthy group, LESV was significantly increased (P<0.05), SV and LVEF were significantly decreased (P<0.05) and T-SD and Tmax were significantly prolonged (P<0.05) in patients implanted with DDD mode cardiac pacemakers. The time to minimal systolic volume of the 16 left ventricular segments time-volume curves differed in patients implanted with DDD mode cardiac pacemakers. Asynchronization of the left ventricular systolic performance in patients implanted with DDD mode cardiac pacemakers was observed. The results showed that RT3DE is a quantitative method used to evaluate left ventricular systolic synchronization.

LIU, LIN; ZHANG, LIANZHONG; DUAN, SHAOBO

2012-01-01

11

Reptilian heart development and the molecular basis of cardiac chamber evolution.  

PubMed

The emergence of terrestrial life witnessed the need for more sophisticated circulatory systems. This has evolved in birds, mammals and crocodilians into complete septation of the heart into left and right sides, allowing separate pulmonary and systemic circulatory systems, a key requirement for the evolution of endothermy. However, the evolution of the amniote heart is poorly understood. Reptilian hearts have been the subject of debate in the context of the evolution of cardiac septation: do they possess a single ventricular chamber or two incompletely septated ventricles? Here we examine heart development in the red-eared slider turtle, Trachemys scripta elegans (a chelonian), and the green anole, Anolis carolinensis (a squamate), focusing on gene expression in the developing ventricles. Both reptiles initially form a ventricular chamber that homogenously expresses the T-box transcription factor gene Tbx5. In contrast, in birds and mammals, Tbx5 is restricted to left ventricle precursors. In later stages, Tbx5 expression in the turtle (but not anole) heart is gradually restricted to a distinct left ventricle, forming a left-right gradient. This suggests that Tbx5 expression was refined during evolution to pattern the ventricles. In support of this hypothesis, we show that loss of Tbx5 in the mouse ventricle results in a single chamber lacking distinct identity, indicating a requirement for Tbx5 in septation. Importantly, misexpression of Tbx5 throughout the developing myocardium to mimic the reptilian expression pattern also results in a single mispatterned ventricular chamber lacking septation. Thus ventricular septation is established by a steep and correctly positioned Tbx5 gradient. Our findings provide a molecular mechanism for the evolution of the amniote ventricle, and support the concept that altered expression of developmental regulators is a key mechanism of vertebrate evolution. PMID:19727199

Koshiba-Takeuchi, Kazuko; Mori, Alessandro D; Kaynak, Bogac L; Cebra-Thomas, Judith; Sukonnik, Tatyana; Georges, Romain O; Latham, Stephany; Beck, Laurel; Beck, Laural; Henkelman, R Mark; Black, Brian L; Olson, Eric N; Wade, Juli; Takeuchi, Jun K; Nemer, Mona; Gilbert, Scott F; Bruneau, Benoit G

2009-09-01

12

Reptilian heart development and the molecular basis of cardiac chamber evolution  

PubMed Central

The emergence of terrestrial life witnessed the need for more sophisticated circulatory systems. This has evolved in birds, mammals, and crocodilians into complete septation of the heart into left and right sides, allowing separate pulmonary and systemic circulatory systems, a key requirement for the evolution of endothermy1–3. However, the evolution of the amniote heart is poorly understood. Reptilian hearts have been the subject of debate in the context of the evolution of cardiac septation: do they possess a single ventricular chamber or two incompletely septated ventricles4–7? We examined heart development in the red-eared slider turtle, Trachemys scripta elegans (a chelonian), and the green anole, Anolis carolinensis (a squamate), focusing on gene expression in the developing ventricles. Both reptiles initially form a ventricular chamber that homogenously expresses the T-box transcription factor gene Tbx5. In contrast, in birds and mammals, Tbx5 is restricted to left ventricle precursors8,9. In later stages, Tbx5 expression in the turtle (but not anole) heart is gradually restricted to a distinct left ventricle, forming a left-right gradient. This suggests that Tbx5 expression was refined during evolution to pattern the ventricles. In support of this hypothesis, we show that loss of Tbx5 in the mouse ventricle results in a single chamber lacking distinct identity, indicating a requirement for Tbx5 in septation. Importantly, misexpression of Tbx5 throughout the developing myocardium to mimic the reptilian expression pattern also results in a single mispatterned ventricular chamber lacking septation. Thus, ventricular septation is established by a steep and correctly positioned Tbx5 gradient. Our findings provide a molecular mechanism for the evolution of the amniote ventricle, and support the concept that altered expression of developmental regulators is a key mechanism of vertebrate evolution.

Koshiba-Takeuchi, Kazuko; Mori, Alessandro D.; Kaynak, Bogac L.; Cebra-Thomas, Judith; Sukonnik, Tatyana; Georges, Romain O.; Latham, Stephany; Beck, Laural; Henkelman, R. Mark; Black, Brian L.; Olson, Eric N.; Wade, Juli; Takeuchi, Jun K.; Nemer, Mona; Gilbert, Scott F.; Bruneau, Benoit G.

2009-01-01

13

Shape and dimensions of cardiac chambers: Importance of CT section thickness and orientation. [Dogs  

Microsoft Academic Search

Three-dimensional (3D) computed tomography (CT) scan data were used to quantitate the geometry of all heart chambers. The Dynamic Spatial Reconstructor (DSR) was used to scan dogs with in situ casts of the cardiac chambers. Chamber volumes estimated from DSR images were accurate within 5% of water displacement volume measurements of the actual casts for chambers greater than 11 ml

E. A. Hoffman; E. L. Ritman

1985-01-01

14

Differentiation between left bundle branch block and left ventricular hypertrophy: implications for cardiac resynchronization therapy.  

PubMed

Recent clinical trials have demonstrated that cardiac resynchronization therapy (CRT) reduces heart failure hospitalizations and mortality in patients with complete left bundle branch block (LBBB), but potentially not those with right bundle branch block or nonspecific LV conduction delay, such as that due to LV hypertrophy (LVH). Furthermore, endocardial mapping and simulation studies have suggested that one-third of patients diagnosed with LBBB by conventional electrocardiographic criteria are misdiagnosed, and these patients likely have a combination of LVH, LV chamber dilatation and delayed initiation of LV activation (incomplete LBBB). Increase in LV size due to hypertrophy/dilatation and slowed intramyocardial conduction velocity prolong QRS duration in patients with LVH, which can frequently go above the QRS duration threshold of 120 ms conventionally used to diagnose LBBB. New strict criteria for diagnosing complete LBBB have been proposed that utilize longer QRS duration thresholds (130 ms in women and 140 ms in men) and require the presence of mid-QRS notching/slurring in at least 2 of the leads I, aVL, V1, V2, V5 or V6. The emergence of CRT has led to an increased need to differentiate complete LBBB from LVH and other types of intraventricular conduction delay, which should be further studied. PMID:23022304

Strauss, David G

2012-09-28

15

Complete rightward cardiac luxation caused due to left tension pneumothorax.  

PubMed

We present a 4-year-old patient with severe rightward cardiac dislocation due to left tension pneumothorax after surgical closure of a perimembranous ventricular septal defect. The chest roentgenograms showed the "dextrocardia-like" appearance of the cardiac silhouette. Given the persistent severe cardiac dislocation despite resolution of the pneumothorax, and considering the patient's ongoing hemodynamic instability, we decided to reopen the chest to return the heart to its natural position. The procedure was uneventful, and the patient was discharged at home on postoperative day 5. PMID:23910116

Federici, Duccio; Vavassori, Angelo; Mantovani, Lorenzo; Cattaneo, Sergio; Ciuffreda, Matteo; Seddio, Francesco; Galletti, Lorenzo

2013-08-01

16

Temporary left-sided mechanical cardiac support during acute myocarditis.  

PubMed

Acute myocarditis is usually a self-limiting viral illness. Rarely, however, myocardial depression can be profound leading to circulatory collapse. Mechanical cardiac support in the form of intraaortic balloon pumps or ventricular assist devices have been used in these unusual cases to maintain systemic perfusion until transplantation or left ventricular recovery occurs. We report a young patient with acute myocarditis who required left heart mechanical support and who, however, was successfully weaned despite only minimal myocardial recovery. PMID:8031810

Kesler, K A; Pruitt, A L; Turrentine, M W; Heimansohn, D A; Brown, J W

17

A novel cardiac MR chamber volume model for mechanical dyssynchrony assessment  

NASA Astrophysics Data System (ADS)

A novel cardiac chamber volume model is proposed for the assessment of left ventricular mechanical dyssynchrony. The tool is potentially useful for assessment of regional cardiac function and identification of mechanical dyssynchrony on MRI. Dyssynchrony results typically from a contraction delay between one or more individual left ventricular segments, which in turn leads to inefficient ventricular function and ultimately heart failure. Cardiac resynchronization therapy has emerged as an electrical treatment of choice for heart failure patients with dyssynchrony. Prior MRI techniques have relied on assessments of actual cardiac wall changes either using standard cine MR images or specialized pulse sequences. In this abstract, we detail a semi-automated method that evaluates dyssynchrony based on segmental volumetric analysis of the left ventricular (LV) chamber as illustrated on standard cine MR images. Twelve sectors each were chosen for the basal and mid-ventricular slices and 8 sectors were chosen for apical slices for a total of 32 sectors. For each slice (i.e. basal, mid and apical), a systolic dyssynchrony index (SDI) was measured. SDI, a parameter used for 3D echocardiographic analysis of dyssynchrony, was defined as the corrected standard deviation of the time at which minimal volume is reached in each sector. The SDI measurement of a healthy volunteer was 3.54%. In a patient with acute myocardial infarction, the SDI measurements 10.98%, 16.57% and 1.41% for basal, mid-ventricular and apical LV slices, respectively. Based on published 3D echocardiogram reference threshold values, the patient's SDI corresponds to moderate basal dysfunction, severe mid-ventricular dysfunction, and normal apical LV function, which were confirmed on echocardiography. The LV chamber segmental volume analysis model and SDI is feasible using standard cine MR data and may provide more reliable assessment of patients with dyssynchrony especially if the LV myocardium is thin or if the MR images have spatial resolution insufficient for proper resolution of wall thickness-features problematic for dyssynchrony assessment using existing MR techniques.

Song, Ting; Fung, Maggie; Stainsby, Jeffrey A.; Hood, Maureen N.; Ho, Vincent B.

2009-02-01

18

Single Site Left Ventricular Pacing for Cardiac Resynchronization  

Microsoft Academic Search

hronic, dilated heart failure is often accompanied by delayed ventricular electrical activation manifested as prolonged QRS duration, most commonly in the form of left bundle branch block (LBBB). Exploration of the link between the sequence of cardiac electrical activation and mechanical function is one of the most exciting contemporary areas of research in heart failure, but recognition of the importance

William G. Stevenson; Michael O. Sweeney

19

Thoracoscopic Left Ventricular Lead Implantation in Cardiac Resynchronization Therapy  

PubMed Central

Cardiac resynchronization therapy is known to reduce morbidity and mortality in patients with advanced heart failure as a result of dyssynchrony and systolic dysfunction of the left ventricle. Placement of the left ventricular (LV) lead via the coronary sinus can be difficult. When LV lead implantation is difficult, a video-assisted epicardial approach can be a good alternative. Although there are several reports of video-assisted epicardial LV lead implantation, mini-thoracotomy and lead implantation under direct vision have been used in most series. A 49-yr-old woman with dilated cardiomyopathy underwent the video-assisted epicardial LV lead implantation because percutaneous transvenous approach was difficult due to small cardiac veins. The patient was discharged without problems and showed improved cardiac function at the 3 follow-up months. We report the first successful total thoracoscopic LV lead implantation (without mini-thoracotomy) in Korea.

Jeong, Dong Seop; Park, Pyo Won; Lee, Young Tak; Park, Seung-Jung; Kim, June Soo

2012-01-01

20

[Primary cardiac leiomyosarcoma originating from the left atrium].  

PubMed

Primary malignant cardiac tumors occur extremely rarely. Among these, leiomyosarcomas are exceptionally rare. We described a case of left atrial leiomyosarcoma in which surgical intervention was followed by adjuvant radiation therapy. A 74-year-old male was admitted for dyspnea. Chest X-ray showed severe pulmonary congestion. Echocardiography revealed large tumor in the left atrium. Emergency operation was performed. The tumor invaded the left atrial wall and the mitral valve, and the lesion was resected as extensively as possible. Postoperative pathologic examination confirmed leiomyosarcoma. He underwent adjuvant radiotherapy postoperatively. However, early local recurrence was recognized. He died due to sudden circulatory collapse in 8th postoperative month. As cardiac leiomyosarcomas have extremely poor prognosis, complete resection and effective postoperative adjuvant therapy are necessary. PMID:23117358

Nakanishi, Harumi; Furukawa, Kojiro; Noguchi, Ryo; Furutachi, Akira; Itoh, Manabu; Kamohara, Keiji; Okazaki, Yukio; Yamasaki, Fumio; Morita, Shigeki

2012-11-01

21

Cardiac catheter complications related to left main stem disease.  

PubMed Central

OBJECTIVE: To examine the incidence and outcome of cardiac catheter complications related to left main coronary artery disease or damage using the CECCC (Confidential Enquiry into Cardiac Catheter Complications) database. SETTING: Coordinating centre for national database. DESIGN: Retrospective analysis of reports to a national multicentre database for cardiac catheter complications. Complications involving the left main coronary artery were flagged at entry. Where necessary additional information was sought from participating centres. 112,921 procedures were registered, 12,849 of which were coronary angioplasties and the remainder diagnostic studies. RESULTS: The total number of cases for which complications were recorded was 993 (0.88%). In 61 (6.14%) of the 993 cases complications were associated with left main coronary disease or damage. In 57 (93%) of these 61 cases complications were major, necessitating resuscitation or immediate coronary bypass grafting. Ten patients (16%) died in the catheter laboratory, a further 9 (15%) within 24 hours, and a total of 23 patients (38%) died within one month of the procedure. Left main stem related complications account for 17% of total mortality in the CECCC database. Urgent coronary bypass grafting was attempted in 42 patients, of whom 31 were alive at one month. In all of the six reported PTCA-related complications the cause was traumatic damage to the left main coronary artery. Operators of all grades of seniority experienced complications in similar proportions. CONCLUSIONS: The risk of a complication relating to the left main stem is relatively low, but when such complications occur they tend to be life-threatening and contribute a fifth of total catheter-related mortality. In the absence of a widely available non-invasive investigation with good predictive value for left main stem disease, the best safeguard is careful technique. Patients who do develop complications should have emergency coronary bypass grafting.

Kovac, J. D.; de Bono, D. P.

1996-01-01

22

[Clinical evaluation of coronary artery fistula and coronary artery-cardiac chamber shunt].  

PubMed

Coronary artery fistula and coronary artery-cardiac chamber shunts were observed in 16 cases out of 462 consecutive cases in which coronary angiography was performed. 9 of these cases had coronary artery fistula, 5 of the cases had coronary artery-cardiac chamber shunts. 2 cases had both of these conditions. Coronary artery fistula has a draining vein originating from the coronary artery and an entering vein terminating in the cardiac chamber or the pulmonary artery. Coronary artery-cardiac chamber shunts have no such veins, and contrast material used in the injection phase of coronary angiography escapes directly into the cardiac chamber. 2 cases of coronary artery fistula, 2 cases of coronary artery-cardiac chamber shunts, and 1 case involving the both of these conditions showed positive results in submaximal exercise tolerance tests, and no significant arteriosclerotic changes in the coronary artery. These factors lead us to suggest that coronary artery-cardiac chamber shunts cause cardiac ischemia for the same reason that coronary artery fistula does. PMID:2320796

Higuchi, H; Takeuchi, M; Shiozaki, A; Tanaka, T; Fukui, A; Kawahira, S; Houda, N; Nakano, T

1990-02-01

23

Left ventricular segmentation of cardiac magnetic resonance images using a novel edge following technique  

Microsoft Academic Search

This paper presents a novel edge following technique for image segmentation designed to segment the left ventricle in cardiac magnetic resonance (MR) images. This is a required step to determine the volume of left ventricle in a cardiac MR image, which is an essential tool for cardiac diagnosis. The traditional method for extracting them from cardiac MR images is by

Krit Somkantha; Nipon Theera-Umpon; Sansanee Auephanwiriyakul

2008-01-01

24

Left Ventricular Hypertrophy Influences Cardiac Prognosis in Patients Undergoing Dobutamine Cardiac Stress Testing  

PubMed Central

Background This study was performed to determine the utility of dobutamine stress test results for predicting myocardial infarction (MI) and cardiac death in patients with chest pain and left ventricular hypertrophy (LVH). Methods and Results Three hundred fifty-three (353) participants, aged 64±12 years (54% men) underwent dobutamine cardiovascular magnetic resonance (DCMR) stress testing and then were followed for 6±2 (range 0.5 to 11.5) years to assess the post-DCMR occurrence of MI or cardiac death. Left ventricular mass and the presence or absence of ischemia were determined; LVH was defined as > 96 g/m2 in men and > 77 g/m2 in women. LVH was present in 62 participants (18 % of the men and 17% of the women, p=0.90). Seventy-one (20%) participants experienced a MI or cardiac death during follow-up. The MI and cardiac death rate was more frequent in those with versus without LVH (32% vs. 17%, p=0.009). In multivariable analysis that accounted for the presence of pre-existing coronary artery disease, hypertension, diabetes, stress induced ischemia, and reduced LVEF, LVH was an independent predictor of MI and cardiac death (hazard ratio = 1.99, 95% confidence interval = 1.13-3.50; p=0.02). Conclusions Left ventricular hypertrophy is predictive of future MI and cardiac death in patients with or without inducible ischemia during dobutamine cardiac stress testing. As a result, LVH should be reported in those referred for dobutamine cardiac stress tests, particularly those without inducible ischemia, in whom otherwise one would assume a favorable cardiac prognosis.

Charoenpanichkit, Charaslak; Morgan, Timothy M.; Hamilton, Craig A.; Wallace, Eric L.; Robinson, Killian; Ntim, William O.; Hundley, W. Gregory

2011-01-01

25

[The process of remodeling of left chambers of the heart and dysfunction of endothelium of peripheral vessels in hypertensive premenopausal women].  

PubMed

Results of ultrasound study of 230 premenopausal women with I-II stage essential hypertension (EH) in relation to functional state of endothelium of peripheral arteries are presented. Endothelial dysfunction in hypertensive premenopausal women can be one of factors contributing to remodeling of left cardiac chamber. Women with EH and endothelial dysfunction compared with those with conserved vascular endothelial function more often had hypertrophic variants of left ventricular myocardial remodeling (mostly of concentric type). Premenopausal women with EH had diastolic dysfunction of the left ventricle with impairment of both its rigidity and active relaxation, more pronounced in the presence of dysfunction of endothelium of peripheral vessels. PMID:19254216

Khabibulina, M M; Serebrennikov, R V; Iordanidi, Ia S; Grishina, I F

2009-01-01

26

Management of Acute Regurgitation in Left-Sided Cardiac Valves  

PubMed Central

The management of acute, severe cardiac valvular regurgitation requires expeditious multidisciplinary care. Although acute, severe valvular regurgitation can be a true surgical emergency, accurate diagnosis and subsequent treatment decisions require clinical acumen, appropriate imaging, and sound judgment. An accurate and timely diagnosis is essential for successful outcomes and requires appropriate expertise and a sufficiently high degree of suspicion in a variety of settings. Whereas cardiovascular collapse is the most obvious and common presentation of acute cardiac valvular regurgitation, findings may be subtle, and the clinical presentation can often be nonspecific. Consequently, other acute conditions such as sepsis, pneumonia, or nonvalvular heart failure may be mistaken for acute valvular regurgitation. In comparison with that of the right-sided valves, regurgitation of the left-sided valves is more common and has greater clinical impact. Therefore, this review focuses on acute regurgitation of the aortic and mitral valves.

Mokadam, Nahush A.; Stout, Karen K.; Verrier, Edward D.

2011-01-01

27

Semi-automatic algorithm for construction of the left ventricular area variation curve over a complete cardiac cycle  

PubMed Central

Background Two-dimensional echocardiography (2D-echo) allows the evaluation of cardiac structures and their movements. A wide range of clinical diagnoses are based on the performance of the left ventricle. The evaluation of myocardial function is typically performed by manual segmentation of the ventricular cavity in a series of dynamic images. This process is laborious and operator dependent. The automatic segmentation of the left ventricle in 4-chamber long-axis images during diastole is troublesome, because of the opening of the mitral valve. Methods This work presents a method for segmentation of the left ventricle in dynamic 2D-echo 4-chamber long-axis images over the complete cardiac cycle. The proposed algorithm is based on classic image processing techniques, including time-averaging and wavelet-based denoising, edge enhancement filtering, morphological operations, homotopy modification, and watershed segmentation. The proposed method is semi-automatic, requiring a single user intervention for identification of the position of the mitral valve in the first temporal frame of the video sequence. Image segmentation is performed on a set of dynamic 2D-echo images collected from an examination covering two consecutive cardiac cycles. Results The proposed method is demonstrated and evaluated on twelve healthy volunteers. The results are quantitatively evaluated using four different metrics, in a comparison with contours manually segmented by a specialist, and with four alternative methods from the literature. The method's intra- and inter-operator variabilities are also evaluated. Conclusions The proposed method allows the automatic construction of the area variation curve of the left ventricle corresponding to a complete cardiac cycle. This may potentially be used for the identification of several clinical parameters, including the area variation fraction. This parameter could potentially be used for evaluating the global systolic function of the left ventricle.

2010-01-01

28

Surgical left cardiac sympathetic denervation for long QT syndrome: effects on QT interval and heart rate  

Microsoft Academic Search

The primary aim of the present study was to investigate the short-term effects of surgical left cardiac sympathetic denervation (LCSD) on the QT interval and heart rate in patients with congenital long QT syndrome (LQTS). Left cardiac sympathetic denervation was performed in five LQTS patients who had a history of syncope. The patients’ 12-lead and 24-h Holter monitoring ECG was

Cuilan Li; Dayi Hu; Lihua Shang; Shan Ma; Wenling Liu; Yuntian Li; Zhimin Ma; Chuzhong Tang; Yunqing Mei; Lexin Wang

2005-01-01

29

Cardiac Resynchronization Therapy and Implantable Cardiac Defibrillators in Left Ventricular Systolic Dysfunction. Evidence Report/Technology Assessment Number 152.  

National Technical Information Service (NTIS)

Cardiac resynchronization therapy (CRT) refers to atrial-synchronized biventricular pacing (i.e., pacing the right atrium, right ventricle, and left ventricle). CRT improves the electrical dyssynchrony found in many patients with heart failure (HF) and th...

B. Vandermeer C. Friesen C. Spooner D. M. Dryden F. A. McAlister J. Ezekowitz N. Hooton

2007-01-01

30

Comparison of ethanol concentrations in right cardiac blood, left cardiac blood and peripheral blood in a series of 30 cases  

Microsoft Academic Search

The aim of this study was to compare ethanol concentrations in right cardiac blood, left cardiac blood and peripheral blood. Samples were taken from a series of 30 medicolegal autopsies. Ethanol was measured by headspace GC-FID. In each case, the degree of putrefaction, chest or abdominal injury, and\\/or regurgitation of gastric contents into the airways were noted. Our results show

Anne-Laure Pelissier-Alicot; Nicolas Coste; Christophe Bartoli; Marie-Dominique Piercecchi-Marti; Alain Sanvoisin; Joanny Gouvernet; Georges Leonetti

2006-01-01

31

Balloon dilation of an imperforate cor triatriatum dexter in a Golden Retriever with concurrent double-chambered right ventricle and subsequent evaluation by cardiac magnetic resonance imaging.  

PubMed

A 12-week-old male Golden Retriever was presented with signs of right-sided congestive heart failure and a grade V/VI left craniosternal systolic murmur. Echocardiography identified a double-chambered right ventricle and dilated coronary sinus (CS) running into an inter-atrial chamber. This was confirmed to be an imperforate cor triatriatum dexter (CTD) by selective angiographic studies. To the authors' knowledge this is the first case reported of imperforate CTD successfully treated by membranostomy and balloon dilation. Cardiac MRI confirmed the echocardiographic and angiographic findings and provided a more precise understanding of the venous abnormalities. PMID:21835710

López-Alvarez, Jordi; Dukes-McEwan, Joanna; Martin, Mike W S; Killick, David; Fonfara, Sonja; Fraser McConnell, J

2011-08-10

32

A left ventricular lipoma diagnosed on three-dimensional electrocardiogram-gated cardiac computed tomography  

Microsoft Academic Search

Cardiac lipomas are extremely rare primary benign cardiac tumors. We describe a patient with a chief complaint of ventricular\\u000a tachycardia associated with a lipoma arising in the left ventricular myocardium. The cardiac lipoma was qualitatively evaluated\\u000a and its location was accurately determined noninvasively with the use of three-dimensional images reconstructed from data\\u000a acquired by electrocardiogram-gated cardiac computed tomography (CT). Our

Hiromitsu Hayashi; Fumitaka Hidaka; Tomonari Kiriyama; Hidetaka Sato; Ryo Takagi; Shinichiro Kumita

2008-01-01

33

A Nondestructive Method for Casting the Cardiac Chambers Post-Mortem  

PubMed Central

A method has been developed that permits accurate casting of cardiac chambers in diastole without macerating or otherwise damaging the heart specimen. The castings accurately reflect the size of all openings, passages and anomalous communications. Comparison with in vivo angiographic studies should prove useful for refining and validating clinical findings. Images

Carlstein, Rudolf G.

1984-01-01

34

Differential requirement for BMP signaling in atrial and ventricular lineages establishes cardiac chamber proportionality.  

PubMed

The function of an organ relies upon the proper relative proportions of its individual operational components. For example, effective embryonic circulation requires the appropriate relative sizes of each of the distinct pumps created by the atrial and ventricular cardiac chambers. Although the differences between atrial and ventricular cardiomyocytes are well established, little is known about the mechanisms regulating production of proportional numbers of each cell type. We find that mutation of the zebrafish type I BMP receptor gene alk8 causes reduction of atrial size without affecting the ventricle. Loss of atrial tissue is evident in the lateral mesoderm prior to heart tube formation and results from the inhibition of BMP signaling during cardiac progenitor specification stages. Comparison of the effects of decreased and increased BMP signaling further demonstrates that atrial cardiomyocyte production correlates with levels of BMP signaling while ventricular cardiomyocyte production is less susceptible to manipulation of BMP signaling. Additionally, mosaic analysis provides evidence for a cell-autonomous requirement for BMP signaling during cardiomyocyte formation and chamber fate assignment. Together, our studies uncover a new role for BMP signaling in the regulation of chamber size, supporting a model in which differential reception of cardiac inductive signals establishes chamber proportion. PMID:19232521

Marques, Sara R; Yelon, Deborah

2009-02-20

35

Differential requirement for BMP signaling in atrial and ventricular lineages establishes cardiac chamber proportionality  

PubMed Central

The function of an organ relies upon the proper relative proportions of its individual operational components. For example, effective embryonic circulation requires the appropriate relative sizes of each of the distinct pumps created by the atrial and ventricular cardiac chambers. Although the differences between atrial and ventricular cardiomyocytes are well established, little is known about the mechanisms regulating production of proportional numbers of each cell type. We find that mutation of the zebrafish type I BMP receptor gene alk8 causes reduction of atrial size without affecting the ventricle. Loss of atrial tissue is evident in the lateral mesoderm prior to heart tube formation and results from the inhibition of BMP signaling during cardiac progenitor specification stages. Comparison of the effects of decreased and increased BMP signaling further demonstrates that atrial cardiomyocyte production correlates with levels of BMP signaling while ventricular cardiomyocyte production is less susceptible to manipulation of BMP signaling. Additionally, mosaic analysis provides evidence for a cell-autonomous requirement for BMP signaling during cardiomyocyte formation and chamber fate assignment. Together, our studies uncover a new role for BMP signaling in the regulation of chamber size, supporting a model in which differential reception of cardiac inductive signals establishes chamber proportion.

Marques, Sara R.; Yelon, Deborah

2009-01-01

36

Nonischemic left ventricular dysfunction after pediatric cardiac transplantation: treatment with plasmapheresis and OKT3  

Microsoft Academic Search

BackgroundAcquired left ventricular dysfunction after pediatric cardiac transplantation is associated with a high mortality rate. It often occurs without biopsy evidence of cellular rejection or severe transplant coronary arteriopathy.

Delwyn McOmber; Jill Ibrahim; Douglas M Lublin; Jeffrey E Saffitz; Catherine Ong-Simon; Eric N Mendeloff; Charles B Huddleston; Charles E Canter

2004-01-01

37

The miR-143-adducin3 pathway is essential for cardiac chamber morphogenesis.  

PubMed

Discovering the genetic and cellular mechanisms that drive cardiac morphogenesis remains a fundamental goal, as three-dimensional architecture greatly impacts functional capacity. During development, accurately contoured chambers balloon from a primitive tube in a process characterized by regional changes in myocardial cell size and shape. How these localized changes are achieved remains elusive. Here, we show in zebrafish that microRNA-143 (miR-143) is required for chamber morphogenesis through direct repression of adducin3 (add3), which encodes an F-actin capping protein. Knockdown of miR-143 or disruption of the miR-143-add3 interaction inhibits ventricular cardiomyocyte F-actin remodeling, which blocks their normal growth and elongation and leads to ventricular collapse and decreased contractility. Using mosaic analyses, we find that miR-143 and add3 act cell-autonomously to control F-actin dynamics and cell morphology. As proper chamber emergence relies on precise control of cytoskeletal polymerization, Add3 represents an attractive target to be fine-tuned by both uniform signals, such as miR-143, and undiscovered localized signals. Together, our data uncover the miR-143-add3 genetic pathway as essential for cardiac chamber formation and function through active adjustment of myocardial cell morphology. PMID:20460367

Deacon, Dekker C; Nevis, Kathleen R; Cashman, Timothy J; Zhou, Yong; Zhao, Long; Washko, Daniel; Guner-Ataman, Burcu; Burns, C Geoffrey; Burns, Caroline E

2010-06-01

38

Use of vital capacity for cardiac failure risk estimation in persons with coronary disease and left ventricular hypertrophy  

Microsoft Academic Search

Cardiac failure is a common lethal outcome of coronary heart disease and left ventricular hypertrophy. The efficacy of forced vital capacity (FVC), measured biennially, in predicting the onset of cardiac failure was explored in 818 Framingham Study subjects with these predisposing conditions, among whom 324 developed cardiac failure. Among the men and women who had coronary disease or left ventricular

William B. Kannel; Ralph B. D'Agostino; Halit Silbershatz

1996-01-01

39

Four-chamber heart modeling and automatic segmentation for 3D cardiac CT volumes  

NASA Astrophysics Data System (ADS)

Multi-chamber heart segmentation is a prerequisite for quantification of the cardiac function. In this paper, we propose an automatic heart chamber segmentation system. There are two closely related tasks to develop such a system: heart modeling and automatic model fitting to an unseen volume. The heart is a complicated non-rigid organ with four chambers and several major vessel trunks attached. A flexible and accurate model is necessary to capture the heart chamber shape at an appropriate level of details. In our four-chamber surface mesh model, the following two factors are considered and traded-off: 1) accuracy in anatomy and 2) easiness for both annotation and automatic detection. Important landmarks such as valves and cusp points on the interventricular septum are explicitly represented in our model. These landmarks can be detected reliably to guide the automatic model fitting process. We also propose two mechanisms, the rotation-axis based and parallel-slice based resampling methods, to establish mesh point correspondence, which is necessary to build a statistical shape model to enforce priori shape constraints in the model fitting procedure. Using this model, we develop an efficient and robust approach for automatic heart chamber segmentation in 3D computed tomography (CT) volumes. Our approach is based on recent advances in learning discriminative object models and we exploit a large database of annotated CT volumes. We formulate the segmentation as a two step learning problem: anatomical structure localization and boundary delineation. A novel algorithm, Marginal Space Learning (MSL), is introduced to solve the 9-dimensional similarity transformation search problem for localizing the heart chambers. After determining the pose of the heart chambers, we estimate the 3D shape through learning-based boundary delineation. Extensive experiments demonstrate the efficiency and robustness of the proposed approach, comparing favorably to the state-of-the-art. This is the first study reporting stable results on a large cardiac CT dataset with 323 volumes. In addition, we achieve a speed of less than eight seconds for automatic segmentation of all four chambers.

Zheng, Yefeng; Georgescu, Bogdan; Barbu, Adrian; Scheuering, Michael; Comaniciu, Dorin

2008-04-01

40

A case with dextrocardia, ventricular septal defect, persistent left superior vena cava and drainage of the great cardiac vein into the left internal thoracic vein  

Microsoft Academic Search

A 17-month-old female patient was operated on for ventricular septal defect and pulmonary stenosis. During the operation several cardiac anomalies were observed these were dextrocardia, ventricular septal defect, persistent left superior vena cava, drainage of the great cardiac vein into the left internal thoracic vein and a pericardial pouch. These anomalies have not previously been reported together.

N. Yener; H. S. Sürücü; R. Dogan; M. M. Aldur

2001-01-01

41

Left ventricular systolic torsion correlates global cardiac performance during dyssynchrony and cardiac resynchronization therapy  

PubMed Central

Left ventricular (LV) systolic torsion is a primary mechanism contributing to stroke volume (SV). We hypothesized that change in LV torsion parallels changes in global systolic performance during dyssynchrony and cardiac resynchronization therapy (CRT). Seven anesthetized open chest dogs had LV pressure-volume relationship. Apical, basal, and mid-LV cross-sectional echocardiographic images were studied by speckle tracking analysis. Right atrial (RA) pacing served as control. Right ventricular (RV) pacing simulated left bundle branch block. Simultaneous RV-LV free wall and RV-LV apex pacing (CRTfw and CRTa, respectively) modeled CRT. Dyssynchrony was defined as the time difference in peak strain between earliest and latest segments. Torsion was calculated as the maximum difference between the apical and basal rotation. RA pacing had minimal dyssynchrony (52 ± 36 ms). RV pacing induced dyssynchrony (189 ± 61 ms, P < 0.05). CRTa decreased dyssynchrony (46 ± 36 ms, P < 0.05 vs. RV pacing), whereas CRTfw did not (110 ± 96 ms). Torsion during baseline RA was 6.6 ± 3.7°. RV pacing decreased torsion (5.1 ± 3.6°, P < 0.05 vs. control), and reduced SV, stroke work (SW), and dP/dtmax compared with RA (21 ± 5 vs. 17 ± 5 ml, 252 ± 61 vs. 151 ± 64 mJ, and 2,063 ± 456 vs. 1,603 ± 424 mmHg/s, respectively, P < 0.05). CRTa improved torsion, SV, SW, and dP/dtmax compared with RV pacing (7.7 ± 4.7°, 23 ± 3 ml, 240 ± 50 mJ, and 1,947 ± 647 mmHg/s, respectively, P < 0.05), whereas CRTfw did not (5.1 ± 3.6°, 18 ± 5 ml, 175 ± 48 mJ, and 1,699 ± 432 mmHg/s, respectively, P < 0.05). LV torsion changes covaried across conditions with SW (y = 0.94x+12.27, r = 0.81, P < 0.0001) and SV (y = 0.66x+0.91, r = 0.81, P < 0.0001). LV dyssynchrony changes did not correlate with SW or SV (r = ?0.12, P = 0.61 and r = 0.08, P = 0.73, respectively). Thus, we conclude that LV torsion is primarily altered by dyssynchrony, and CRT that restores LV performance also restores torsion.

Lamia, Bouchra; Tanabe, Masaki; Tanaka, Hidekazu; Kim, Hyung Kook; Gorcsan, John

2011-01-01

42

Dual-Chamber Pacing for Cardiac Arrhythmias: Controversies in Cloning the Conduction System  

PubMed Central

From the outset, the art and science of cardiac pacing has been beset with a variety of problems. With the passage of time and concentrated effort in the interrelated sciences, many have been solved. We no longer are concerned with premature battery failure or leaking pulse-generator capsules, but now focus on an entirely new set of issues that beg for resolution. Foremost among these is the true role of dual-chamber pacing in the treatment of slow and fast cardiac arrhythmias of a multitude of etiologies. Secondary to that issue is the cascade of problems brought about by a burgeoning of technical capabilities, such as micro-miniaturized computing devices, complex pacemaker programmability with telemetry functions, the impact of these technologies on therapeutic indications and techniques, the proliferation of pacemaker utilization, and the summative socioeconomic implications.

Parsonnet, Victor; Bernstein, Alan D.; Norman, John C.

1984-01-01

43

Left ventricular outflow tract obstruction: should cardiac screening be offered to first-degree relatives?  

Microsoft Academic Search

ObjectivesTo determine whether offering cardiac screening to relatives of patients with left ventricular outflow tract obstructions (LVOTOs) would be justified.BackgroundLVOTOs have been recognised as a group of congenital heart diseases with ‘high heritability’. One of the LVOTOs, the bicuspid aortic valve, is often asymptomatic, but has become known to be associated with sudden, unexpected cardiac death. However, the need for

Wilhelmina S Kerstjens-Frederikse; Gideon J Du Marchie Sarvaas; Jolien S Ruiter; Peter C Van Den Akker; Arno M Temmerman; Joost P Van Melle; Robert M W Hofstra; Rolf M F Berger

2011-01-01

44

Left ventricular non-compaction and its cardiac and neurologic implications.  

PubMed

Left ventricular non-compaction, also known as left ventricular hypertrabeculation (LVHT), is a morphological abnormality of the left ventricular myocardium, characterised by a meshwork of myocardial strings, interlacing, and orderless in arrangement. LVHT is most frequently located in the apex and the lateral wall and may occur with or without other congenital or acquired cardiac abnormalities. LVHT is believed to be congenital in the majority of the cases but may develop during life in single cases (acquired LVHT). Congenital LVHT is believed to result from defective late-stage embryonic development of the myocardial architecture. The pathogenesis of acquired LVHT remains speculative. LVHT is most frequently found on transthoracic echocardiography and cardiac MRI but may be visualised also with other imaging techniques. In the majority of the cases, LVHT is associated with hereditary cardiac, neuromuscular, non-cardiac/non-muscle disease, or chromosomal aberrations. In the majority of the cases, LVHT is complicated by ventricular arrhythmias, systolic dysfunction, cardiac embolism, or sudden cardiac death. LVHT per se does not require a specific treatment. Only in case of complications, such as ventricular arrhythmias, cardioembolism, or systolic dysfunction, adequate therapy is indicated. Though initially assessed as poor, the prognosis of LVHT has meanwhile improved, most likely due to the increased awareness for the abnormality and the timely administration of adequate therapy. PMID:20549343

Finsterer, Josef

2010-11-01

45

Iatrogenic left internal mammary artery to great cardiac vein anastomosis treated with coil embolization.  

PubMed

Inadvertent left internal mammary artery (LIMA)-great cardiac vein (GCV) anastomosis is a rare complication of coronary artery bypass graft surgery. Patients with iatrogenic aortocoronary fistula (ACF) were usually treated surgical repair, percutaneous embolic occlusion with coil or balloon. We report a case of iatrogenic LIMA to GCV anastomosis successfully treated with coil embolization and protected left main coronary intervention through the percutaneous transfemoral approach. PMID:21430997

Jung, Il Soon; Jeong, Jin-Ok; Kim, Song Soo; Shin, Byung Seok; Shin, Sung Kyun; Park, Yong Kyu; Jin, Seon-Ah; Ahn, Kye Taek; Seong, In-Whan

2011-02-28

46

Cardiac tamponade due to left ventricular pseudoaneurysm after aortic valve replacement.  

PubMed

Left ventricular outflow tract pseudoaneurysm is a rare but a potentially lethal complication, mainly after aortic root endocarditis or surgery. Usually, it originates from a dehiscence in the mitral-aortic intervalvular fibrosa and arises posteriorly to the aortic root. We report a rare case of a patient with cardiac tamponade due to left ventricular pseudoaneurysm after aortic valve replacement. The subsequent surgical resection was performed successfully. PMID:23439359

Baydar, Onur; Co?kun, Ugur; Balaban, Betul; Cetin, Gurkan; Firatli, Inci; Ersanli, Murat Kazim; Kucukoglu, Mehmet Serdar

2013-02-01

47

Automatic functional analysis of left ventricle in cardiac cine MRI  

PubMed Central

Rationale and objectives A fully automated left ventricle segmentation method for the functional analysis of cine short axis (SAX) magnetic resonance (MR) images was developed, and its performance evaluated with 133 studies of subjects with diverse pathology: ischemic heart failure (n=34), non-ischemic heart failure (n=30), hypertrophy (n=32), and healthy (n=37). Materials and methods The proposed automatic method locates the left ventricle (LV), then for each image detects the contours of the endocardium, epicardium, papillary muscles and trabeculations. Manually and automatically determined contours and functional parameters were compared quantitatively. Results There was no significant difference between automatically and manually determined end systolic volume (ESV), end diastolic volume (EDV), ejection fraction (EF) and left ventricular mass (LVM) for each of the four groups (paired sample t-test, ?=0.05). The automatically determined functional parameters showed high correlations with those derived from manual contours, and the Bland-Altman analysis biases were small (1.51 mL, 1.69 mL, –0.02%, –0.66 g for ESV, EDV, EF and LVM, respectively). Conclusions The proposed technique automatically and rapidly detects endocardial, epicardial, papillary muscles’ and trabeculations’ contours providing accurate and reproducible quantitative MRI parameters, including LV mass and EF.

Lu, Ying-Li; Connelly, Kim A.; Dick, Alexander J.; Wright, Graham A.

2013-01-01

48

Synthetic prostacycline agonist, ONO1301, ameliorates left ventricular dysfunction and cardiac fibrosis in cardiomyopathic hamsters  

Microsoft Academic Search

Impairment of cardiac function in cardiomyopathy has been postulated to be related to decreased blood flow and increased collagen synthesis. Administration of growth factors was reported to attenuate left ventricular (LV) remodeling and dysfunction in animal models of dilated cardiomyopathy. We previously reported that ONO-1301, a synthetic prostacyclin agonist with thromboxane-synthase inhibitory activity, promotes production of hepatocyte growth factor and

Yoichiro Hirata; Takeshi Soeki; Masashi Akaike; Yoshiki Sakai; Takashi Igarashi; Masataka Sata

2009-01-01

49

Left ventricular morphology, global and longitudinal function in normal older individuals: A cardiac magnetic resonance study  

Microsoft Academic Search

BackgroundThe heart transforms structurally and functionally with age but the nature and magnitude of reported changes appear inconsistent. This study was designed to assess left ventricular (LV) morphology, global and longitudinal function in healthy older men and women using cardiac magnetic resonance (CMR).

Nikolay P. Nikitin; Poay Huan Loh; Ramesh de Silva; Klaus K. A. Witte; Elena I. Lukaschuk; Anita Parker; T. Alan Farnsworth; Farqad M. Alamgir; Andrew L. Clark; John G. F. Cleland

2006-01-01

50

Surgical Treatment of Late Tricuspid Regurgitation after Left Cardiac Valve Replacement  

Microsoft Academic Search

Background. The development of late tricuspid regurgitation (TR) following left cardiac valve replacement is an important complication, as it is associated with a severe impairment of exercise capacity and a poor symptomatic outcome. The pathogenesis of this condition remains poorly defined. It is still a challenge in terms of its prevention, treatment and indications for surgical correction.Aims. To investigate the

Xue-jun Xiao; Huan-lei Huang; Jing-fang Zhang; Ruo-bin Wu; Jing-gong He; Cong Lu; Zhong-min Li

2004-01-01

51

Cardiac transplant outcome of patients supported on left ventricular assist device vs intravenous inotropic therapy  

Microsoft Academic Search

BackgroundAlthough the left ventricular assist device (LVAD) has been increasingly used as a bridge to transplant, its effect on post-transplant outcome is uncertain. We, therefore, designed this study using the Cardiac Transplant Research Database to compare patients supported on an LVAD before transplant with those treated with intravenous inotropic medical therapy.

Brian E Jaski; Joseph C Kim; David C Naftel; John Jarcho; Maria Rosa Costanzo; Howard J Eisen; James K Kirklin; Robert C Bourge

2001-01-01

52

Effects of vasopressin on left anterior descending coronary artery blood flow during extremely low cardiac output  

Microsoft Academic Search

Because of the possibility of vasopressin-mediated coronary vasospasm, this study was designed to assess effects of vasopressin compared to saline placebo on left anterior descending (LAD) coronary artery blood flow. Twelve anaesthetized domestic swine were prepared for LAD coronary artery blood flow measurement with ultrasonic flow probes, using cardiopulmonary by-pass adjusted to 10% of the prearrest cardiac output. This 10%

Viktoria D Mayr; Volker Wenzel; Tilko Müller; Herwig Antretter; Klaus Rheinberger; Karl H Lindner; Hans-Ulrich Strohmenger

2004-01-01

53

Left ventricular systolic strain of the cardiac allograft evaluated with three-dimensional speckle tracking echocardiography.  

PubMed

Three-dimensional speckle tracking echocardiography was employed to evaluate the changes of left ventricular systolic strain in 23 heart transplant recipients at 1st, 3rd, 6th and 12th month after heart transplantation, and 23 healthy subjects served as controls. The three-dimensional full-volume echocardiographic images of left ventricle were recorded and then were analyzed using EchoPAC software. The strain curves and peak systolic strain values for each segment and overall left ventricular wall were obtained. Left ventricular global peak longitudinal strain (GPSL), global peak radial strain (GPSR), global peak circumferential strain (GPSC) and global peak area strain (GPSA) were measured and then statistically analyzed. There were no significant differences in left ventricular ejection fraction (LVEF) and cardiac output (CO) between heart transplant recipients and controls. The GPSL in heart transplant recipients at 1st month after surgery was significantly lower than that in controls, but close to the normal value at 3rd month after surgery and later. The GPSC, GPSA and GPSR were significantly lower in heart transplant recipients at 1st, 3rd, 6th and 12th month after surgery than those in controls. It is suggested that three-dimensional speckle tracking echocardiography can be used for monitoring changes of left ventricular systolic strains and evaluating left ventricular systolic function in cardiac allograft. PMID:24142734

Liu, Hong-Yun; Deng, You-Bin; Liu, Kun; Li, Yang; Tang, Qiao-Ying; Wei, Xiang; Chang, Sheng; Lu, Xia

2013-10-20

54

An image-based comprehensive approach for automatic segmentation of left ventricle from cardiac short axis cine MR images.  

PubMed

Segmentation of the left ventricle is important in the assessment of cardiac functional parameters. Manual segmentation of cardiac cine MR images for acquiring these parameters is time-consuming. Accuracy and automation are the two important criteria in improving cardiac image segmentation methods. In this paper, we present a comprehensive approach to segment the left ventricle from short axis cine cardiac MR images automatically. Our method incorporates a number of image processing and analysis techniques including thresholding, edge detection, mathematical morphology, and image filtering to build an efficient process flow. This process flow makes use of various features in cardiac MR images to achieve high accurate segmentation results. Our method was tested on 45 clinical short axis cine cardiac images and the results are compared with manual delineated ground truth (average perpendicular distance of contours near 2 mm and mean myocardium mass overlapping over 90%). This approach provides cardiac radiologists a practical method for an accurate segmentation of the left ventricle. PMID:20623156

Huang, Su; Liu, Jimin; Lee, Looi Chow; Venkatesh, Sudhakar K; Teo, Lynette Li San; Au, Christopher; Nowinski, Wieslaw L

2011-08-01

55

Left ventricular diastolic dysfunction of the cardiac surgery patient; a point of view for the cardiac surgeon and cardio-anesthesiologist  

Microsoft Academic Search

BACKGROUND: Left ventricular diastolic dysfunction (DD) is defined as the inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest, while left atrial pressure does not exceed 12 mm Hg. We examined the concept of left ventricular diastolic dysfunction in a cardiac surgery setting. MATERIALS AND METHODS: Literature review was carried

Efstratios E Apostolakis; Nikolaos G Baikoussis; Haralabos Parissis; Stavros N Siminelakis; Georgios S Papadopoulos

2009-01-01

56

Turning crocodilian hearts into bird hearts: growth rates are similar for alligators with and without right-to-left cardiac shunt.  

PubMed

The functional and possible adaptive significance of non-avian reptiles' dual aortic arch system and the ability of all non-avian reptiles to perform central vascular cardiac shunts have been of great interest to comparative physiologists. The unique cardiac anatomy of crocodilians - a four-chambered heart with the dual aortic arch system - allows for only right-to-left (R-L; pulmonary bypass) cardiac shunt and for surgical elimination of this shunt. Surgical removal of the R-L shunt, by occluding the left aorta (LAo) upstream and downstream of the foramen of Panizza, results in a crocodilian with an obligatory, avian/mammalian central circulation. In this study, R-L cardiac shunt was eliminated in age-matched, female American alligators (Alligator mississippiensis; 5-7 months of age). We tested the hypothesis that surgical elimination of R-L cardiac shunt would impair growth (a readily measured proxy for fitness) compared with sham-operated, age-matched controls, especially in animals subjected to exhaustive exercise. While regular exercise caused a decrease in size (snout-to-vent length, head length and body mass), elimination of the capacity for R-L cardiac shunt did not greatly reduce animal growth, despite a chronic ventricular enlargement in surgically altered juvenile alligators. We speculate that, despite being slightly smaller, alligators with an occluded LAo would have reached sexual maturity in the same breeding season as control alligators. This study suggests that crocodilian R-L cardiac shunt does not provide an adaptive advantage for juvenile alligator growth and supports the logic that cardiac shunts persist in crocodilians because they have not been selected against. PMID:20639429

Eme, John; Gwalthney, June; Owerkowicz, Tomasz; Blank, Jason M; Hicks, James W

2010-08-01

57

Cardiac Cycle Dependent Left Atrial Dynamics: Implications for Catheter Ablation of Atrial Fibrillation  

PubMed Central

Background Left atrial volume (LAV) determines prognosis and response to therapy in atrial fibrillation. Integration of electro-anatomical maps with 3D-images rendered from CT and MRI is used to facilitate atrial fibrillation ablation. Objectives We measured LAV changes and regional motion during the cardiac cycle that might affect the accuracy of image integration and determined their relationship to standard LAV measurements. Methods MRI was performed in thirty patients with paroxysmal atrial fibrillation. Left atrial time-volume curves were generated and used to divide the left atrial function (LAEF) into pumping (PEF) and conduit (CEF) fractions and to determine the maximum LAV (LAMAX) and the pre-atrial contraction volume (PACV). LAV was measured using an MRI angiogram and traditional geometric models from echocardiography (area-length and ellipsoid). The in-plane displacement of the pulmonary veins, anterior left atrium, mitral annulus, and left atrial appendage was measured. Results LAMAX was 107±36ml and occurred at 42±5% of the RR interval. PACV was 86 ±34ml and occurred at 81±4% of the RR interval. LAEF was 45±10% and PEF was 31±10%. LAV measurements made from the MRI angiogram, area-length and ellipsoid models underestimated LAMAX by 21±25ml, 16±26ml, and 35±22ml, respectively. The anterior LA, mitral annulus, and left atrial appendage were significantly displaced during the cardiac cycle (8.8±2.0mm, 13.2±3.8mm, and 10.2±3.4mm, respectively); the pulmonary veins were not. Conclusions LAV changes significantly during the cardiac cycle and substantial regional variation in left atrial motion exists. Standard measurements of left atrial volume significantly underestimate LAMAX when compared to the gold standard measure of 3D-volumetrics.

Patel, Amit R.; Fatemi, Omid; Norton, Patrick T.; West, J. Jason; Helms, Adam S.; Kramer, Christopher M.; Ferguson, John D.

2008-01-01

58

Cardiac phase-targeted dynamic load on left ventricle differentially regulates phase-sensitive gene expressions and pathway activation.  

PubMed

The heart has remarkable capacity to adapt to mechanical load and to dramatically change its phenotype. The mechanism underlying such diverse phenotypic adaptations remains unknown. Since systolic overload induces wall thickening, while diastolic overload induces chamber enlargement, we hypothesized that cardiac phase-sensitive mechanisms govern the adaptation. We inserted a balloon into the left ventricle (LV) of a Langendorff perfused rat heart, and controlled LV volume (LVV) using a high performance servo-pump. We created isolated phasic systolic overload (SO) by isovolumic contraction (peak LV pressure >170mmHg) at unstressed diastolic LVV [end-diastolic pressure (EDP)=0mmHg]. We also created pure phasic diastolic overload (DO) by increasing diastolic LVV until EDP >40mmHg and unloading completely in systole. After 3hours under each condition, the myocardium was analyzed using DNA microarray. Gene expressions under SO and DO conditions were compared against unloaded control condition using gene ontology and pathway analysis (n=4 each). SO upregulated proliferation-related genes, whereas DO upregulated fibrosis-related genes (P<10(-5)). Both SO and DO upregulated genes related functionally to cardiac hypertrophy, although the gene profiles were totally different. Upstream regulators confirmed by Western blot indicated that SO activated extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, and Ca(2+)/calmodulin-dependent protein kinase II (3.2-, 2.0-, and 4.7-fold versus control, P<0.05, n=5), whereas DO activated p38 (2.9-fold, P<0.01), which was consistent with the downstream gene expressions. In conclusion, pure isolated systolic and diastolic overload permits elucidation of cardiac phase-sensitive gene regulation. The genomic responses indicate that mechanisms governing the cardiac phase-sensitive adaptations are different. PMID:24004468

Onitsuka, Ken; Ide, Tomomi; Arai, Shinobu; Hata, Yuko; Murayama, Yoshinori; Hosokawa, Kazuya; Sakamoto, Takafumi; Tobushi, Tomoyuki; Sakamoto, Kazuo; Fujino, Takeo; Sunagawa, Kenji

2013-09-01

59

The role of cardiac magnetic resonance imaging in differentiating the underlying causes of left ventricular hypertrophy  

PubMed Central

The onset of sudden cardiac death and large inter- and intra-familial clinical variability of hypertrophic cardiomyopathy pose an important clinical challenge. Cardiac magnetic resonance imaging is a high-resolution imaging modality that has become increasingly available in the past decade and has the unique possibility to demonstrate the presence of fibrosis or scar using late gadolinium enhancement imaging. As a result, the diagnostic and prognostic potential of cardiac magnetic resonance imaging has been extensively explored in acute and chronic ischaemic cardiomyopathy, as well as in several nonischaemic cardiomyopathies. This review aims to provide a critical overview of recently published studies on hypertrophic cardiomyopathy and discusses the role of cardiac magnetic resonance imaging in differentiating underlying causes of hypertrophic cardiomyopathy, such as familial hypertrophic cardiomyopathy, cardiac involvement in systemic disease and left ventricular hypertrophy due to endurance sports. Also, it demonstrates the use of cardiac magnetic resonance in risk stratification for the onset of sudden cardiac death, and early identification of asymptomatic family members of hypertrophic cardiomyopathy patients who are at risk for the development of hypertrophic cardiomyopathy. (Neth Heart J 2010;18:135–43.20390064) PMID:20390064

Germans, T.; Nijveldt, R.; Brouwer, W.P.; Groothuis, J.G.J.; Beek, A.M.; Gotte, M.J.W.; van Rossum, A.C.

2010-01-01

60

Computer-aided scheme for functional index computation of left ventricle in cardiac CTA: segmentation and partitioning of left ventricle  

NASA Astrophysics Data System (ADS)

Cardiac functional indices, such as ejection fraction and regional wall motion/ thickening, are commonly used for assessing the contractility and functionality of the heart in clinical practice. An important step for computer-aided determination of functional indices is the automated segmentation of the heart from computed tomography angiography (CTA) and the partitioning of the left ventricle into 16 segments. We develop a fully automatic scheme which not only segments the whole heart from cardiac CTA images, but also partitions the left ventricle, including the blood pool and myocardium, into 16 segments of bull's eye plot. The segmentation is based on image registration and atlas propagation techniques, whereas the bull's eye plot is first obtained through atlas propagation and then further improved to correct inconsistency across different subjects, uneven size for each segment and "zig-zag" edges between them. In this preliminary study, a cohort of ten clinical CTA data was employed to compute and evaluate the regional functional indices as well as the global indices.

Huang, Hui; Zhuang, Xiahai; Shao, Yi; Lan, Tian; Liu, Liu; Li, Qiang

2013-02-01

61

TEE-guided left ventricular epicardial pacing lead placement for cardiac resynchronization therapy.  

PubMed

Biventricular pacing has demonstrated improvement in cardiac functions in treating congestive cardiac failure patients. Recent trials have proven the clinical and functional benefits of cardiac resynchronization therapy in severe heart failure and intraventricular cardiac delays, mainly left bundle branch block. Biventricular pacing improves the exercise tolerance, quality of life, systolic heart function, reduces hospitalization and slows progression of the disease. A 54-year-old lady, a known case of dilated cardiomyopathy, was on biventricular pacing since 2 years. She presented in emergency with sudden deterioration of dyspnea to NYHA class III/IV. When investigated, the coronary sinus lead was found displaced; thus, left ventricle (LV) was not getting paced. After multiple failures to reposition the coronary sinus lead, it was decided to surgically place the epicardial lead for LV pacing under general anesthesia. Lateral thoracotomy was done and LV pacing lead was placed at different sites with simultaneous monitoring of cardiac output (CO) and stroke volume (SV) by transesophageal echocardiography (TEE). Baseline CO and SV were 1.9 l/min and 19.48 ml respectively and increased at different sites of pacing at LV, the best CO and SV were 4.2 l/min and 42.39 ml respectively on lateral surface. Intraoperative TEE can calculate beat to beat stroke volume and thus CO and helps to choose optimal site for placement of epicardial pacing lead. PMID:22772517

Arya, Rajesh Chand; Sood, Naresh Kumar; Ralhan, Sarju; Wander, Gurpreet Singh

62

Neurological symptoms and cerebrovascular accidents: manifestations of left-sided cardiac tumours in adults  

PubMed Central

We present two adult patients with a left-sided cardiac tumour in whom the diagnosis was established by transthoracic and transoesophageal echocardiography. They both presented with a cerebrovascular accident. Cardiac surgery for tumour excision was offered but refused by one and successfully performed in the other. In one of the patients, right femoro-crural bypass was undertaken because of arterial insufficiency. The patient who refused surgical intervention died secondary to severe septic shock. In the other patient serial transthoracic and transoesophageal echocardiography showed no tumour recurrence at four years of follow-up post tumour extirpation. ImagesFigure 1Figure 2Figure 3Figure 4

Said, S.A.M.; Droste, H.T.; Baart, J.C.; Klaver, M.M.; Sie, H.T.

2004-01-01

63

Prognostic Value of Left Ventricular Diastolic Dysfunction in Patients Undergoing Cardiac Catheterization for Coronary Artery Disease  

PubMed Central

We hypothesized that left ventricular (LV) diastolic dysfunction assessed by cardiac catheterization may be associated with increased risk for cardiovascular events. To test the hypothesis, we assessed diastolic function by cardiac catheterization (relaxation time constant (Tau) and end-diastolic pressure (EDP)) as well as Doppler echocardiography (early diastolic mitral annular velocity (e?) and a ratio of early diastolic mitral inflow to annular velocities (E/e?)) in 222 consecutive patients undergoing cardiac catheterization for coronary artery disease (CAD). During a followup of 1364 ± 628 days, 5 cardiac deaths and 20 unscheduled cardiovascular hospitalizations were observed. Among LV diastolic function indices, Tau > 48?ms and e? < 5.8?cm/s were each significantly associated with lower rate of survival free of cardiovascular hospitalization. Even after adjustment for potential confounders (traditional cardiovascular risk factors, the severity of CAD, and cardiovascular medications), the predictive value of Tau > 48?ms and e? < 5.8?cm/s remained significant. No predictive value was observed in EDP, E/e?, or LV ejection fraction. In conclusion, LV diastolic dysfunction, particularly impaired LV relaxation assessed by both cardiac catheterization and Doppler echocardiography, is independently associated with increased risk for cardiac death or cardiovascular hospitalization in patients with known or suspected CAD.

Fukuta, Hidekatsu; Ohte, Nobuyuki; Wakami, Kazuaki; Goto, Toshihiko; Tani, Tomomitsu; Kimura, Genjiro

2012-01-01

64

Prognostic value of left ventricular diastolic dysfunction in patients undergoing cardiac catheterization for coronary artery disease.  

PubMed

We hypothesized that left ventricular (LV) diastolic dysfunction assessed by cardiac catheterization may be associated with increased risk for cardiovascular events. To test the hypothesis, we assessed diastolic function by cardiac catheterization (relaxation time constant (Tau) and end-diastolic pressure (EDP)) as well as Doppler echocardiography (early diastolic mitral annular velocity (e') and a ratio of early diastolic mitral inflow to annular velocities (E/e')) in 222 consecutive patients undergoing cardiac catheterization for coronary artery disease (CAD). During a followup of 1364 ± 628 days, 5 cardiac deaths and 20 unscheduled cardiovascular hospitalizations were observed. Among LV diastolic function indices, Tau > 48?ms and e' < 5.8?cm/s were each significantly associated with lower rate of survival free of cardiovascular hospitalization. Even after adjustment for potential confounders (traditional cardiovascular risk factors, the severity of CAD, and cardiovascular medications), the predictive value of Tau > 48?ms and e' < 5.8?cm/s remained significant. No predictive value was observed in EDP, E/e', or LV ejection fraction. In conclusion, LV diastolic dysfunction, particularly impaired LV relaxation assessed by both cardiac catheterization and Doppler echocardiography, is independently associated with increased risk for cardiac death or cardiovascular hospitalization in patients with known or suspected CAD. PMID:22567531

Fukuta, Hidekatsu; Ohte, Nobuyuki; Wakami, Kazuaki; Goto, Toshihiko; Tani, Tomomitsu; Kimura, Genjiro

2012-04-12

65

Acquired left coronary artery fistula draining to the cardiac vein system after acute myocardial infarction revealed by CT scan.  

PubMed

Coronary artery fistula (CAF) is a congenital condition characterized by a pathological communication between a coronary artery and a systemic vein or one of the cardiac chambers. Iatrogenic CAFs were reported to develop secondary to the rupture of coronary aneurysm. Instances of acquired CAF draining into the cardiac chambers have been described after acute myocardial infarction. Angiography is the gold standard in diagnosing CAF. We describe the case of a patient who developed a fistula draining into the middle cardiac vein on the posterior interventricular sulcus, after acute myocardial infarction, revealed by CT scan. PMID:21872131

Cassese, Salvatore; Cirillo, Plinio; Dellegrottaglie, Santo; Piscione, Federico; Chiariello, Massimo

66

Improvement of Left Ventricular Function After Cardiac Resynchronization Therapy Is Predicted by Tissue Doppler Imaging Echocardiography  

Microsoft Academic Search

Background—Cardiac resynchronization therapy was shown to reverse left ventricular (LV) remodeling in patients with congestive heart failure (CHF). However, the prediction of benefit is controversial. We aimed to investigate predictive factors of LV functional recovery and reversed remodeling after biventricular pacing. Methods and Results—Forty-nine consecutive patients with CHF and a wide QRS complex (18232 ms) were studied by echocardiography before

Martin Penicka; Jozef Bartunek; Bernard De Bruyne; Marc Vanderheyden; Marc Goethals; Marc De Zutter; Pedro Brugada; Peter Geelen

2010-01-01

67

Impact of weightlessness on cardiac shape and left ventricular stress/strain distributions.  

PubMed

In this paper, a finite element model of the heart is developed to investigate the impact of different gravitational loadings of Earth, Mars, Moon, and microgravity on the cardiac shape and strain/stress distributions in the left ventricle. The finite element model is based on realistic 3D heart geometry, detailed fiber/sheet micro-architecture, and a validated orthotropic cardiac tissue model and constitutive relationship that capture the passive behavior of the heart at end-diastole. The model predicts the trend and magnitude of cardiac shape change at different gravitational levels with great fidelity in comparison to recent cardiac sphericity measurements performed during simulated reduced-gravity parabolic flight experiments. Moreover, the numerical predictions indicate that although the left ventricular strain distributions remain relatively unaltered across the gravitational fields and the strain extrema values occur at the same relative locations, their values change noticeably with decreasing gravity. As for the stress, however, both the magnitude and location of the extrema change with a decrease in the gravitational field. Consequently, tension regions of the heart on Earth can change into compression regions in space. PMID:24048335

Iskovitz, Ilana; Kassemi, Mohammad; Thomas, James D

2013-12-01

68

Pitx2 regulates cardiac left–right asymmetry by patterning second cardiac lineage-derived myocardium  

Microsoft Academic Search

Current models of left–right asymmetry hold that an early asymmetric signal is generated at the node and transduced to lateral plate mesoderm in a linear signal transduction cascade through the function of the Nodal signaling molecule. The Pitx2 homeobox gene functions at the final stages of this cascade to direct asymmetric morphogenesis of selected organs including the heart. We previously

Di Ai; Wei Liu; Lijiang Ma; Feiyan Dong; Mei-Fang Lu; Degang Wang; Michael P. Verzi; Chenleng Cai; Philip J. Gage; Sylvia Evans; Brian L. Black; Nigel A. Brown; James F. Martin

2006-01-01

69

Structure and torsion in the normal and situs inversus totalis cardiac left ventricle. II. Modeling cardiac adaptation to mechanical load.  

PubMed

Mathematical models provide a suitable platform to test hypotheses on the relation between local mechanical stimuli and responses to cardiac structure and geometry. In the present model study, we tested hypothesized mechanical stimuli and responses in cardiac adaptation to mechanical load on their ability to estimate a realistic myocardial structure of the normal and situs inversus totalis (SIT) left ventricle (LV). In a cylindrical model of the LV, 1) mass was adapted in response to myofiber strain at the beginning of ejection and to global contractility (average systolic pressure), 2) cavity volume was adapted in response to fiber strain during ejection, and 3) myofiber orientations were adapted in response to myofiber strain during ejection and local misalignment between neighboring tissue parts. The model was able to generate a realistic normal LV geometry and structure. In addition, the model was also able to simulate the instigating situation in the rare SIT LV with opposite torsion and transmural courses in myofiber direction between the apex and base [Delhaas et al. (6)]. These results substantiate the importance of mechanical load in the formation and maintenance of cardiac structure and geometry. Furthermore, in the model, adapted myocardial architecture was found to be insensitive to fiber misalignment in the transmural direction, i.e., myofiber strain during ejection was sufficient to generate a realistic transmural variation in myofiber orientation. In addition, the model estimates that, despite differences in structure, global pump work and the mass of the normal and SIT LV are similar. PMID:18424633

Kroon, Wilco; Delhaas, Tammo; Bovendeerd, Peter; Arts, Theo

2008-04-18

70

[Left atrial myxoma who presented cardiac arrest immediately after the onset of coldness of a leg; report of a case].  

PubMed

A 55-year-old woman visited the emergency department of our hospital with complaint of coldness and pain in her right leg. Two hours after the onset, she suddenly felt dyspnea and temporarily suffered cardiac arrest. Echocardiography revealed a left atrial tumor prolapsing into the left ventricle through the mitral valve. By emergency operation, both the cardiac tumor and the embolus were diagnosed as myxomas. The postoperative course was uneventful. Cardiac failure and arterial embolism are major symptoms of a left atrial myxoma, but there have been no reports of both symptoms occurring at the same time. It is supposed that the changing form of the tumor because of embolus separation could have caused heart failure. We must consider the use of echocardiography to examine cardiac tumors in patients with arterial embolism who do not have cardiac arrhythmias. PMID:23023550

Tano, Kazutoshi; Ichikawa, Yoichi

2012-10-01

71

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

PubMed

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

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

2013-11-01

72

Left ventricular dysfunction is a risk factor for sudden cardiac death in adults late after repair of tetralogy of fallot  

Microsoft Academic Search

ObjectivesThe purpose of this study was to determine if left ventricular (LV) systolic dysfunction was also a predictor of sudden cardiac death (SCD) in adults late after repair of tetralogy of Fallot (TOF).

Akash Ghai; Candice Silversides; Louise Harris; Gary D. Webb; Samuel C. Siu; Judith Therrien

2002-01-01

73

Tissue doppler imaging predicts improved systolic performance and reversed left ventricular remodeling during long-term cardiac resynchronization therapy  

Microsoft Academic Search

ObjectivesWe sought to evaluate the long-term impact of cardiac resynchronization therapy (CRT) on left ventricular (LV) performance and remodeling using three-dimensional echocardiography and tissue Doppler imaging (TDI).

Peter Søgaard; Henrik Egeblad; W. Yong Kim; Henrik K. Jensen; Anders K. Pedersen; Bent Ø. Kristensen; Peter T. Mortensen

2002-01-01

74

Left main coronary artery atresia and associated cardiac defects: report on concomitant surgical treatment.  

PubMed

A 9-year-old boy with congenital atresia of the left main coronary artery underwent myocardial revascularization. Coarctation of the aorta and ventricular septal defect were diagnosed at the age of 1 year. At age 7 years, the child presented with syncope while exercising. Preoperative evaluation included cardiac catheterization which revealed the unexpected finding of congenital atresia of the left main coronary artery with origin of the circumflex artery from the right coronary artery. Surgical correction included myocardial revascularization by means of left internal mammary artery graft to the anterior descending coronary artery, coarctation resection, and ventricular septal defect repair. The patient recovered uneventfully. We report the details of this extremely rare case with successful concomitant surgical management of the congenital coronary artery anomaly and the associated structural heart disease. PMID:23804483

Jatene, Marcelo; Juaneda, Ignacio; Miranda, Rogerio Dos Anjos; Gato, Rafaella; Marcial, Miguel Lorenzo Barbero

2011-10-01

75

Comparison of Acute Alterations in Left Ventricular Relaxation and Diastolic Chamber Stiffness Induced by Hypoxia and Ischemia  

PubMed Central

To clarify conflicting reports concerning the effects of ischemia on left ventricular chamber stiffness, we compared the effects of hypoxia at constant coronary perfusion with those of global ischemia on left ventricular diastolic chamber stiffness using isolated, perfused rabbit hearts in which the left ventricle was contracting isovolumically. Since chamber volume was held constant, increases in left ventricular end diastolic pressure (LVEDP) reflected increases in chamber stiffness. At a control coronary flow rate (30 ml/min), 2 min of hypoxia and pacing tachycardia (4.0 Hz) produced major increases in postpacing LVEDP (10±1 to 24±3 mm Hg, P < 0.01) and the relaxation time constant, T, (40±4 to 224±37 ms, P < 0.001), while percent lactate extraction ratio became negative (+ 18±2 to ?48±15%, P < 0.001). Coronary perfusion pressure decreased (72±5 to 52±3 mm Hg, P < 0.01), and since coronary flow was held constant, the fall in coronary perfusion pressure reflected coronary dilation and a decrease in coronary vascular resistance. Following an average of 71±6s reoxygenation and initial heart rate (2.0 Hz), LVEDP and relaxation time constant T returned to control. Hypoxia alone (without pacing tachycardia) produced similar although less marked changes (LVEDP, 10±1 to 20±3 mm Hg; and T, 32±3 to 119±22 ms; P < 0.01 for both) and there was a strong correlation between LVEDP and T (r = 0.82, P < 0.001). When a similar degree of coronary vasodilatation was induced with adenosine, no change in LVEDP occurred, indicating that the increase in end diastolic pressure observed during hypoxia was not secondary to vascular engorgement, but due to an acute effect of hypoxia on the diastolic behavior of the ventricular myocardium. In contrast, global ischemia produced by low coronary flow (12?15 ml/min) resulted in a decrease in LVEDP, as well as a marked fall in left ventricular systolic pressure. In 14 global ischemia experiments, pacing tachycardia led to a further decline in left ventricular systolic pressure, and no increase was noted in postpacing LVEDP. Changes in lactate extraction ratio were much smaller in magnitude than with hypoxia and constant coronary perfusion. In two experiments (one at normal coronary flow and one at 15 ml/min), left ventricular systolic pressure did not change markedly from control when tachycardia was superimposed, and postpacing LVEDP showed a marked rise (to > 25 mm Hg), which gradually recovered over 1?2 min at the control heart rate. From these results, we conclude that left ventricular chamber stiffness increases when myocardial O2 demand exceeds supply. This change is usually masked in ischemic (reduced coronary flow) preparations, perhaps because of reduced turgor of the coronary vascular bed, marked reductions in systolic work (and therefore myocardial O2 requirements), and local accumulation of hydrogen ion and metabolites following acute severe reduction of coronary flow. The increased chamber stiffness during hypoxia is accompanied by marked slowing of relaxation, with increased diastolic pressure relative to volume persisting throughout diastole.

Serizawa, Takashi; Vogel, W. Mark; Apstein, Carl S.; Grossman, William

1981-01-01

76

Left ventricular non-compaction cardiomyopathy mimicking an infiltrative cardiac disease.  

PubMed

A 60-year-old male patient, with coronary artery bypass graft due to coronary artery disease 9 years ago, without a history of prior myocardial infarction, was referred to our clinic for further cardiologic evaluation. Routine transthoracic echocardiography showed a slightly reduced left ventricular function with a massive left ventricular hypertrophy located mainly to the anterolateral and inferolateral segments, including basal segments and papillary muscles, mimicking a myocardial infiltrative disease, e.g. cardiac amyloidosis. Echocardiographic criteria for left ventricular non-compaction cardiomyopathy (LVNC) were not fulfilled. For further evaluation of the unusual asymmetric wall thickening, an echocardiographic examination with a left heart contrast agent was conducted. Deep intertrabecular recesses of the anterolateral and inferolateral segments could now be unmasked. Left ventricular hypertrabeculation-noncompaction represents rare abnormalities, diagnosed when many left ventricular trabeculations are visibly apical to the papillary muscles and intertrabecular spaces are perfused from the ventricular cavity. To our knowledge, this is the first report of a patient with LVNC mimicking an infiltrative myocardial disease in echocardiography. This case represents a possible pitfall in the diagnosis of LVNC, which could sometimes be avoided by using LV opacification agents. PMID:19232764

Buss, Sebastian J; Mereles, Derliz; Katus, Hugo A; Hardt, Stefan E

2009-02-20

77

Long-term follow-up of neonatal coarctation and left-sided cardiac hypoplasia.  

PubMed

Neonatal coarctation of the aorta (CoA) is often associated with hypoplastic left-sided cardiac structures. Limited data are available regarding the long-term clinical outcomes. Our purposes were to assess the following in neonates with CoA and left-sided cardiac hypoplasia: (1) left-sided cardiac structure growth over time, (2) echocardiographic parameters predicting reintervention, and (3) long-term outcomes and reintervention rates. Data were collected for all patients born with isolated CoA, along with a mitral or aortic Z-score of <-2, who underwent repair before 2 months of age from January 1993 to April 1997. Recent follow-up data were available for 51 of 63 patients (81%) aged 15.4 ± 1.5 years (range 11 to 18). Of the 51 patients, 46 (90%) had a recent echocardiogram, all with normal left ventricular systolic function. The mitral and aortic valve annulus Z-scores increased significantly from the initial measurements: -3.29 ± 1.54 to -0.94 ± 0.58 (p <0.0001) and -3.25 ± 1.98 to 0.08 ± 1.81 (p <0.0001). No significant change was seen from intermediate (6.1 ± 1.6 years) to the latest follow-up examination. Of the 51 patients, 12 (24%) required reintervention at 3 ± 4.5 years; 9 for repeat CoA, 4 for subaortic stenosis, and 2 for aortic stenosis (some in combination). The initial echocardiographic parameters were not associated with reintervention. The overall freedom from reintervention was 76% at 15 years of follow-up. In conclusion, the long-term outcomes after isolated CoA repair with associated left-sided cardiac hypoplasia were excellent. Both aortic and mitral valve sizes had increased substantially by intermediate follow-up but tended to normalize afterward. Although 24% of the patients required reintervention, significant left ventricular inflow or outflow tract obstruction was uncommon. PMID:23428075

Gray, Robert G; Tani, Lloyd Y; Weng, Hsin Yi; Puchalski, Michael D

2013-02-19

78

New generation 3-dimensional echocardiography for left ventricular volumetric and functional measurements: Comparison with cardiac magnetic resonance  

Microsoft Academic Search

Aims: Non-invasive assessment of left ventricular (LV) structure and func- tion is important in the evaluation of cardiac patients. This study was designed to test the accuracy and reproducibility of new generation 3-dimensional echocardiography (3DE) in measuring volumetric and functional LV indices as compared with current ''gold standard'' of non-invasive cardiac imaging, cardiac magnetic resonance (CMR). Methods and results: Sixty-four

Nikolay P. Nikitin; Cristina Constantin; Poay Huan Loh; Justin Ghosh; Elena I. Lukaschuk; Anna Bennett; Sarah Hurren; Farqad Alamgir; Andrew L. Clark; John G. F. Cleland

79

Automated detection of the left ventricular region in gated nuclear cardiac imaging.  

PubMed

An approach to automated outlining the left ventricular contour and its bounded area in gated isotopic ventriculography is proposed. Its purpose is to determine the ejection fraction (EF), an important parameter for measuring cardiac function. The method uses a modified version of the fuzzy C-means (MFCM) algorithm and a labeling technique. The MFCM algorithm is applied to the end diastolic (ED) frame and then the (FCM) is applied to the remaining images in a "box" of interest. The MFCM generates a number of fuzzy clusters. Each cluster is a substructure of the heart (left ventricle,...). A cluster validity index to estimate the optimum clusters number present in image data point is used. This index takes account of the homogeneity in each cluster and is connected to the geometrical property of data set. The labeling is only performed to achieve the detection process in the ED frame. Since the left ventricle (LV) cluster has the greatest area of the cardiac images sequence in ED phase, a framing operation is performed to obtain, automatically, the "box" enclosing the LV cluster. THe EF assessed in 50 patients by the proposed method and a semi-automatic one, routinely used, are presented. A good correlation between the two methods EF values is obtained (R = 0.93). The LV contour found has been judged very satisfactory by a team of trained clinicians. PMID:8626193

Boudraa, A E; Arzi, M; Sau, J; Champier, J; Hadj-Moussa, S; Besson, J E; Sappey-Marinier, D; Itti, R; Mallet, J J

1996-04-01

80

Mechanism of hemodynamic improvement by dual-chamber pacing for severe left ventricular dysfunction: An acute Doppler and catheterization hemodynamic study  

Microsoft Academic Search

Objectives. This study was undertaken to determine the mechanism by which improvement in hemodynamic variables may occur with dual-chamber pacing in patients with severe left ventricular dysfunction.Background. Dual-chamber pacing has recently been proposed as a therapeutic alternative for the relief of symptoms in patients with dilated cardiomyopathy.Methods. Fifteen patients with severe left ventricular systolic dysfunction were studied acutely during atrioventricular

Rick A. Nishimura; David L. Hayes; David R. Holmes; Jamil Tajik

1995-01-01

81

Left ventricular thrombus mimicking primary cardiac tumor in a patient with primary antiphospholipid syndrome and recurrent systemic embolism  

Microsoft Academic Search

Primary antiphospholipid syndrome (APS) is a well-defined entity characterized by spontane- ous and recurrent abortion, thrombocytopenia and recurrent vascular thromboses (arterial and venous). Left ventricular thrombus mimicking primary cardiac tumor with recurrent systemic embolism has not been previously reported. In this report we describe a 39 year-old man admitted to hospital presenting with left hemi- paresis and a peripheral embolism.

F. Cianciulli; Jorge A. Lax; Roberto O. Neme; Sebastian Fandino Lound; Coloma E. Parisi; Horacio A. Prezioso; Luis A. Vidal

82

Routine left atrial catheterization for the post-operative management of cardiac surgical patients: is the risk justified?  

Microsoft Academic Search

Objective: To assess the risk\\/benefit ratio, including cost, associated with routine left atrial catheterization for the post-operative management of patients after cardiac surgery. Methods: From November 1991 to June 1998, out of 6187 open heart procedures performed at our institution, 5815 patients (94%) receive a left atrial monitoring line inserted invasively by a unique and reproducible technique. Catheters were removed

Francesco Santini; Giuseppe Gatti; Valentino Borghetti; Guido Oppido; Alessandro Mazzucco

1999-01-01

83

Prevalence of cardiac right left shunts in migraine: a population-based case-control study.  

PubMed

We aimed to investigate the prevalence of cardiac right left shunts (RLS) in population-based samples of subjects with migraine with aura (n = 42), migraine without aura (n = 44) and controls without headache (n = 41). Cardiac RLS was assessed with transcranial Doppler sonography with intravenous injection of saline. Prevalence of RLS was highest in migraineurs with aura (45.2%) compared to migraineurs without aura (34.1%) and controls (41.5%). Permanent as opposed to latent RLS was more common among patients with migraine with aura (40.5%) than in patients with migraine without aura (23.3%) or controls (24.4%). Differences did not reach statistical significance between the three groups (p = 0.564 for RLS prevalence, p = 0.349 for prevalence of permanent shunts). Our data implicate a trend towards higher prevalence of RLS with larger shunts in subjects with migraine with aura. PMID:22367223

Küper, Michael; Rabe, Kasja; Holle, Dagny; Savidou, Irini; Dommes, Peter; Frings, Markus; Diener, Hans Christoph; Katsarava, Zaza

2012-02-25

84

The cardiac support device and the myosplint: treating heart failure by targeting left ventricular size and shape.  

PubMed

Left ventricular (LV) remodeling occurs in patients with heart failure and is associated with poor long-term outcome. Two important components of this remodeling process are progressive LV dilation and LV shape changes, the latter manifested by increased LV chamber sphericity. This brief review describes two passive mechanical devices that were developed to prevent the progressive LV dilation and shape changes that occur during the evolution of heart failure. One such device is the Cardiac Support Device ([CSD] CorCap; Acorn Cardiovascular, St Paul, MN) and the other is the Myosplint (Myocor, Maple Grove, MN). Studies in dogs with coronary microembolization-induced heart failure have shown that the CSD prevents progressive LV dilation, increases LV ejection fraction, lowers LV wall stress, and attenuates LV chamber sphericity. Safety and feasibility studies in patients with heart failure have shown that the CSD is safe. The same studies have provided strong efficacy trends that are consistent with those seen in experimental animals. Studies in dogs with rapid pacing induced heart failure showed that the Myosplint device can reshape the LV leading to reduced LV volumes, increased ejection fraction, and reduced wall stress. Safety and feasibility studies of the Myosplint device in humans are limited and trends are not as yet easily discerned. Final conclusions on the clinical effectiveness of these devices must await completion of randomized clinical trials. These trials should provide the first tests in humans of the hypothesis that limiting LV remodeling alone can improve long-term outcome and quality of life in patients with heart failure. PMID:12820730

Sabbah, Hani N

2003-06-01

85

Pharmacologic cardiac resynchronization of a 1-year-old boy with severe left ventricular dysfunction.  

PubMed

Postero-septal accessory pathways (AP) are a rare cause of intraventricular dyssynchrony and severe LV dysfunction in children. Beside the common treatment with radiofrequency ablation of septal substrates we present the case of a successful pharmacologic resynchronization in a 13/12 years old male toddler with Wolff-Parkinson-White syndrome (WPW) and severe LV dysfunction (left ventricular biplane EF of 31 %) due to intraventricular dyssynchrony with septal to posterior wall motion delay (SPWMD) of 350 ms. Interventricular mechanical delay (IVMD) was 65 ms. Using propafenone, pharmacologic cardiac resynchronization could be achieved. Pharmacologic resynchronization should be considered as safe and effective alternative to catheter ablation in very young children. PMID:22484822

Paech, Christian; Flosdorff, Patrick; Gebauer, Roman Antonin

2012-04-07

86

Sinus Node Dysfunction as the First Manifestation of Left Ventricular Noncompaction with Multiple Cardiac Abnormalities  

PubMed Central

Left ventricular noncompaction (LVNC) is a genetically heterogenous form of cardiomyopathy which may remain undiagnosed till adulthood due to the late presentation of typical symptoms such as dyspnea, congestion, ventricular arrhythmias and thromboembolism. Symptomatic bradycardia secondary to persistent sinus node dysfunction is very rare. Coexistent cardiac defects are common in children however in adults the disease is usually in isolated form. Here, we present a case of twenty-three year-old female LVNC patient with patent ductus arteriosus, bicuspid aortic valve and persistent sinus node dysfunction who presented with dizziness as the first manifestation of the disease.

Gungor, Baris; Alper, Ahmet T; Celebi, Ahmet; Bolca, Osman

2013-01-01

87

Recommendations for chamber quantification  

Microsoft Academic Search

Abstract Quantification of cardiac chamber size, ventricular mass and function ranks among,the most,clinically important,and most,frequently,requested,tasks of echocardiography. Over the last decades, echocardiographic methods and techniques haveimprovedandexpandeddramatically,duetotheintroductionofhigherfrequency transducers, harmonic imaging, fully digital machines, left-sided contrast agents, and other technological advancements. Furthermore, echocardiography due to its porta- bility and versatility is now used in emergency rooms, operating rooms, and intensive care units.

Roberto M. Lang; Michelle Bierig; Richard B. Devereux; Frank A. Flachskampf; Elyse Foster; Patricia A. Pellikka; Michael H. Picard; Mary J. Roman; James Seward; Jack Shanewise; Scott Solomon; Kirk T. Spencer; John Sutton; William Stewart

2006-01-01

88

Tomotherapy and Multifield Intensity-Modulated Radiotherapy Planning Reduce Cardiac Doses in Left-Sided Breast Cancer Patients With Unfavorable Cardiac Anatomy  

Microsoft Academic Search

Purpose: For patients with left-sided breast cancers, radiation treatment to the intact breast results in high doses to significant volumes of the heart, increasing the risk of cardiac morbidity, particularly in women with unfavorable cardiac anatomy. We compare helical tomotherapy (TOMO) and inverse planned intensity modulated radiation therapy (IMRT) with three-dimensional conformal radiotherapy using opposed tangents (3D-CRT) for reductions in

Alan B. Coon; Adam Dickler; Michael C. Kirk; Yixiang Liao; Anand P. Shah; Jonathan B. Strauss; Sea Chen; Julius Turian; Katherine L. Griem

2010-01-01

89

CCT Imaging: Cardiac Electrophysiology Applications  

Microsoft Academic Search

Cardiovascular computed tomography (CCT) can comprehensively assess cardiovascular structure and function relevant to the assessment, treatment, and follow-up of patients with electrophysiologically related disease processes. CT provides 3-D visualization of cardiac chambers, coronary vessels, and thoracic vasculature including structures particularly important to cardiac electrophysiology including the coronary veins, pulmonary veins, and left atrium. This comprehensive technology is extremely useful in

Jerold S. Shinbane

90

Increased emergence of alpha activity over the left but not the right temporal lobe within a dark acoustic chamber: differential response of the left but not the right hemisphere to transcerebral magnetic fields  

Microsoft Academic Search

The percentages of alpha activity per minute over the left and right temporal lobes were measured for the first and second successive 15-min intervals while subjects wore opaque goggles within an acoustic chamber. A weak (5 ?T), burst-firing magnetic field was presented during this period for 1 s every 4 s primarily over the left or the right cerebral hemisphere.

M. A. Persinger

1999-01-01

91

Electrical storm: Role of stellate ganglion blockade and anesthetic implications of left cardiac sympathetic denervation  

PubMed Central

An electrical storm is usually associated with catecholaminergic surge following myocardial ischaemia and manifest as recurrent ventricular arrhythmias, requiring frequent DC shocks. Delivering repeated DC shocks induces myocardial damage and further worsens the arrhythmias, which are resistant to the antiarrhythmic drugs. Cardiac sympathetic blockade abates the excessive catecholaminergic drive and help pacifying the malignant ventricular arrhythmias. We treated the electrical storm in a 52-year-old male with ultrasound-guided left sympathetic ganglion block followed by surgical left cardiac sympathetic denervation. The patient remained symptom-free without any incident of ventricular arrhythmias for 8 months after the surgery. The ultrasonography during blockade of the stellate ganglion enhances the success rate of the technique, reduces the quantity of local anaesthetic required to produce desired effects and prevents technical complications. Supraclavicular surgical access to the upper thoracic sympathetic chain obviates the necessity for one lung ventilation and lateral decubitus during surgery, when the patient is in hemodynamically unstable condition. Sympathectomy can be performed under general anaesthesia taking cautions to avoid sympathetic stimulation in intraoperative period.

Gadhinglajkar, Shrinivas; Sreedhar, Rupa; Unnikrishnan, M.; Namboodiri, Narayanan

2013-01-01

92

Surgical removal of right-to-left cardiac shunt in the American alligator (Alligator mississippiensis) causes ventricular enlargement but does not alter apnoea or metabolism during diving.  

PubMed

Crocodilians have complete anatomical separation between the ventricles, similar to birds and mammals, but retain the dual aortic arch system found in all non-avian reptiles. This cardiac anatomy allows surgical modification that prevents right-to-left (R-L) cardiac shunt. A R-L shunt is a bypass of the pulmonary circulation and recirculation of oxygen-poor blood back to the systemic circulation and has often been observed during the frequent apnoeic periods of non-avian reptiles, particularly during diving in aquatic species. We eliminated R-L shunt in American alligators (Alligator mississippiensis) by surgically occluding the left aorta (LAo; arising from right ventricle) upstream and downstream of the foramen of Panizza (FoP), and we tested the hypotheses that this removal of R-L shunt would cause afterload-induced cardiac remodelling and adversely affect diving performance. Occlusion of the LAo both upstream and downstream of the FoP for approximately 21 months caused a doubling of RV pressure and significant ventricular enlargement (average approximately 65%) compared with age-matched, sham-operated animals. In a separate group of recovered, surgically altered alligators allowed to dive freely in a dive chamber at 23 degrees C, occlusion of the LAo did not alter oxygen consumption or voluntary apnoeic periods relative to sham animals. While surgical removal of R-L shunt causes considerable changes in cardiac morphology similar to aortic banding in mammals, its removal does not affect the respiratory pattern or metabolism of alligators. It appears probable that the low metabolic rate of reptiles, rather than pulmonary circulatory bypass, allows for normal aerobic dives. PMID:19837897

Eme, John; Gwalthney, June; Blank, Jason M; Owerkowicz, Tomasz; Barron, Gildardo; Hicks, James W

2009-11-01

93

Surgical removal of right-to-left cardiac shunt in the American alligator (Alligator mississippiensis) causes ventricular enlargement but does not alter apnoea or metabolism during diving  

PubMed Central

SUMMARY Crocodilians have complete anatomical separation between the ventricles, similar to birds and mammals, but retain the dual aortic arch system found in all non-avian reptiles. This cardiac anatomy allows surgical modification that prevents right-to-left (R–L) cardiac shunt. A R–L shunt is a bypass of the pulmonary circulation and recirculation of oxygen-poor blood back to the systemic circulation and has often been observed during the frequent apnoeic periods of non-avian reptiles, particularly during diving in aquatic species. We eliminated R–L shunt in American alligators (Alligator mississippiensis) by surgically occluding the left aorta (LAo; arising from right ventricle) upstream and downstream of the foramen of Panizza (FoP), and we tested the hypotheses that this removal of R–L shunt would cause afterload-induced cardiac remodelling and adversely affect diving performance. Occlusion of the LAo both upstream and downstream of the FoP for ?21 months caused a doubling of RV pressure and significant ventricular enlargement (average ?65%) compared with age-matched, sham-operated animals. In a separate group of recovered, surgically altered alligators allowed to dive freely in a dive chamber at 23°C, occlusion of the LAo did not alter oxygen consumption or voluntary apnoeic periods relative to sham animals. While surgical removal of R–L shunt causes considerable changes in cardiac morphology similar to aortic banding in mammals, its removal does not affect the respiratory pattern or metabolism of alligators. It appears probable that the low metabolic rate of reptiles, rather than pulmonary circulatory bypass, allows for normal aerobic dives.

Eme, John; Gwalthney, June; Blank, Jason M.; Owerkowicz, Tomasz; Barron, Gildardo; Hicks, James W.

2009-01-01

94

Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function.  

PubMed

In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart. PMID:23743396

Bermejo, Javier; Yotti, Raquel; Villar, Candelas Pérez Del; Del Álamo, Juan C; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Carlos Antoranz, J; Mar Desco, M; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

2013-06-06

95

An unusual case of giant cardiac fibroelastoma mimicking left atrial myxoma in a patient presenting with syncope.  

PubMed

Cardiac papillary fibroelastomas are the most common primary valvular tumors. Generally benign, they account only for about 10% of all primary cardiac neoplasms, can occur in normal or diseased hearts, and are associated strongly with open heart surgery and radiotherapy. They are, in most cases, incidental findings, but can be discovered after syncope. We report the case of an elderly female, who was referred for syncope and was found to have a large fibroelastoma at the mitral valve annulus, intermittently obstructing the left ventricular inflow tract, and mimicking the presentation of left atrial myxoma. This case illustrates another potential mechanism of syncope in patients with fibroelastomas. PMID:22505235

Khoueiry, Georges; Geha, Fady; Meghani, Mustafain; Abi Rafeh, Nidal; Azab, Basem; Torbey, Estelle; Asgarian, Kourosh T; Sicat, Michael

2012-04-14

96

Defining left bundle branch block in the era of cardiac resynchronization therapy.  

PubMed

Cardiac resynchronization therapy (CRT) has emerged as an attractive intervention to improve left ventricular mechanical function by changing the sequence of electrical activation. Unfortunately, many patients receiving CRT do not benefit but are subjected to device complications and costs. Thus, there is a need for better selection criteria. Current criteria for CRT eligibility include a QRS duration ? 120 ms. However, QRS morphology is not considered, although it can indicate the cause of delayed conduction. Recent studies have suggested that only patients with left bundle branch block (LBBB) benefit from CRT, and not patients with right bundle branch block or nonspecific intraventricular conduction delay. The authors review the pathophysiologic and clinical evidence supporting why only patients with complete LBBB benefit from CRT. Furthermore, they review how the threshold of 120 ms to define LBBB was derived subjectively at a time when criteria for LBBB and right bundle branch block were mistakenly reversed. Three key studies over the past 65 years have suggested that 1/3 of patients diagnosed with LBBB by conventional electrocardiographic criteria may not have true complete LBBB, but likely have a combination of left ventricular hypertrophy and left anterior fascicular block. On the basis of additional insights from computer simulations, the investigators propose stricter criteria for complete LBBB that include a QRS duration ? 140 ms for men and ? 130 ms for women, along with mid-QRS notching or slurring in ? 2 contiguous leads. Further studies are needed to reinvestigate the electrocardiographic criteria for complete LBBB and the implications of these criteria for selecting patients for CRT. PMID:21376930

Strauss, David G; Selvester, Ronald H; Wagner, Galen S

2011-03-15

97

Left Ventricular Flow Analysis: Recent Advances in Numerical Methods and Applications in Cardiac Ultrasound  

PubMed Central

The left ventricle (LV) pumps oxygenated blood from the lungs to the rest of the body through systemic circulation. The efficiency of such a pumping function is dependent on blood flow within the LV chamber. It is therefore crucial to accurately characterize LV hemodynamics. Improved understanding of LV hemodynamics is expected to provide important clinical diagnostic and prognostic information. We review the recent advances in numerical and experimental methods for characterizing LV flows and focus on analysis of intraventricular flow fields by echocardiographic particle image velocimetry (echo-PIV), due to its potential for broad and practical utility. Future research directions to advance patient-specific LV simulations include development of methods capable of resolving heart valves, higher temporal resolution, automated generation of three-dimensional (3D) geometry, and incorporating actual flow measurements into the numerical solution of the 3D cardiovascular fluid dynamics.

Borazjani, Iman; Westerdale, John; McMahon, Eileen M.; Rajaraman, Prathish K.; Heys, Jeffrey J.

2013-01-01

98

Left ventricular diastolic dysfunction of the cardiac surgery patient; a point of view for the cardiac surgeon and cardio-anesthesiologist  

PubMed Central

Background Left ventricular diastolic dysfunction (DD) is defined as the inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest, while left atrial pressure does not exceed 12 mm Hg. We examined the concept of left ventricular diastolic dysfunction in a cardiac surgery setting. Materials and methods Literature review was carried out in order to identify the overall experience of an important and highly underestimated issue: the unexpected adverse outcome due to ventricular stiffness, following cardiac surgery. Results Although diverse group of patients for cardiac surgery could potentially affected from diastolic dysfunction, there are only few studies looking in to the impact of DD on the postoperative outcome; Trans-thoracic echo-cardiography (TTE) is the main stay for the diagnosis of DD. Intraoperative trans-oesophageal (TOE) adds to the management. Subgroups of DD can be defined with prognostic significance. Conclusion DD with elevated left ventricular end-diastolic pressure can predispose to increased perioperative mortality and morbidity. Furthermore, DD is often associated with systolic dysfunction, left ventricular hypertrophy or indeed pulmonary hypertension. When the diagnosis of DD is made, peri-operative attention to this group of patients becomes mandatory.

2009-01-01

99

Cardiac MRI segmentation using mutual context information from left and right ventricle.  

PubMed

In this paper, we propose a graphcut method to segment the cardiac right ventricle (RV) and left ventricle (LV) by using context information from each other. Contextual information is very helpful in medical image segmentation because the relative arrangement of different organs is the same. In addition to the conventional log-likelihood penalty, we also include a "context penalty" that captures the geometric relationship between the RV and LV. Contextual information for the RV is obtained by learning its geometrical relationship with respect to the LV. Similarly, RV provides geometrical context information for LV segmentation. The smoothness cost is formulated as a function of the learned context which helps in accurate labeling of pixels. Experimental results on real patient datasets from the STACOM database show the efficacy of our method in accurately segmenting the LV and RV. We also conduct experiments on simulated datasets to investigate our method's robustness to noise and inaccurate segmentations. PMID:23354341

Mahapatra, Dwarikanath

2013-10-01

100

Association of Left-Heart Dysfunction with Severe Exacerbation of Chronic Obstructive Pulmonary Disease Diagnostic Performance of Cardiac Biomarkers  

Microsoft Academic Search

Rationale: Cardiac biomarkers are used to distinguish acute dyspnea due to left-heart dysfunction from that of pulmonary origin. How- ever, they have not been assessed in the specific setting of acute exacerbation of chronic obstructive pulmonary disease (AECOPD), where they might be released without left-heart impairment. Objective: To assess the accuracy of troponin T and of amino-terminal pro-brain natriuretic peptide

Fekri Abroug; Lamia Ouanes-Besbes; Noureddine Nciri; Noura Sellami; Faouzi Addad; Khaldoun Ben Hamda; Adel Ben Amor; Mohamed F. Najjar; Jalel Knani

101

Left ventricular mass and atrial volume determined by cine magnetic resonance imaging in essential hypertension  

Microsoft Academic Search

To evaluate the relationship between left atrial volume determined by cine magnetic resonance imaging and progression of left ventricular hypertrophy (LVH), left atrial volume and echocardiographic left ventricular mass (LVM) were measured in 30 hypertensive patients (15 without LVH and 15 with LVH) and 10 normotensive control subjects. We also evaluated the effects of antihypertensive therapy on the cardiac chamber

Kazuaki Mineoi; Yuji Shigematsu; Takaaki Ochi; Kunio Hiwada

2000-01-01

102

Left ventricular dyssynchrony predicts benefit of cardiac resynchronization therapy in patients with end-stage heart failure before pacemaker implantation  

Microsoft Academic Search

We evaluated patients with end-stage heart failure who have a high likelihood of response to cardiac resynchronization therapy (biventricular pacing). It appears that 20% of patients do not respond to this expensive therapy despite the use of selection criteria (dilated cardiomyopathy, heart failure, New York Heart Association class II or IV, left ventricular ejection fraction 120 ms). The presence of

Jeroen J. Bax; Thomas H. Marwick; Sander G. Molhoek; Gabe B. Bleeker; Lieselot van Erven; Eric Boersma; Paul Steendijk; Ernst E. van der Wall; Martin J. Schalij

2003-01-01

103

Traditional Cardiovascular Risk Factors in Relation to Left Ventricular Mass, Volume, and Systolic Function by Cardiac Magnetic Resonance Imaging  

Microsoft Academic Search

OBJECTIVES The goal of this study was to examine the cross-sectional associations of cardiovascular risk factors with left ventricular (LV) geometry and systolic function measured by cardiac magnetic resonance imaging (MRI) in the Multiethnic Study of Atherosclerosis (MESA). BACKGROUND Cardiovascular risk factors including hypertension, smoking, and obesity are known to be associated with increased LV mass, but less is known

Susan R. Heckbert; Wendy Post; Gregory D. N. Pearson; Donna K. Arnett; Antoinette S. Gomes; Michael Jerosch-Herold; W. Gregory Hundley; Joao A. Lima; David A. Bluemke

2006-01-01

104

Cardiac arrest associated with sildenafil ingestion in a patient with an abnormal origin of the left coronary artery: case report  

PubMed Central

Background Left coronary artery arising from the right sinus of Valsalva is an uncommon congenital coro-nary anomaly that seems to be associated with sudden death in young patients. Case presentation We report a case of cardiac arrest in a 59-year-old patient after sexual intercourse and Silde-nafil ingestion. A coronary arteriography and an angiographic computed tomography scan subsequently revealed a LCA origin from the right aortic sinus along with an intramural course of the left main stem. In addition a distal stenosis of the right coronary artery was detected. After successful resuscitation without neurological deficits coronary artery bypass surgery was performed. Conclusion To our knowledge, this is the first report demonstrating sudden cardiac arrest associated with Sildenafil ingestion in a patient with this type of coronary anomaly. The question arises, whether a cardiac screening is necessary before a Sildenafil therapy is initiated.

2011-01-01

105

Cardiac Looping and the Left-Right Axis: Integrating Morphologic, Molecular, and Genetic Analyses of Vertebrate Left-Right Asymmetry  

Microsoft Academic Search

\\u000a Comparative vertebrate anatomy reveals a strikingly diverse complexity of heart structures, ranging from the more familiar\\u000a four-chambered hearts of mammals and avians to the three-chambered forms of reptiles, amphibians, and fish. Yet, despite variations\\u000a in anatomic form, the functionality of all vertebrate hearts is the same: to support and maintain separation of pulmonary\\u000a and systemic blood flow. To this end,

Ann F. Ramsdell; H. Joseph Yost

106

Optimized temporary bi-ventricular pacing improves haemodynamic function after on-pump cardiac surgery in patients with severe left ventricular systolic dysfunction: a two-centre randomized control trial  

PubMed Central

OBJECTIVES Optimized temporary bi-ventricular (BiV) pacing may benefit heart failure patients after on-pump cardiac surgery compared with conventional dual-chamber right ventricular (RV) pacing. An improvement in haemodynamic function with BiV pacing may reduce the duration of ‘Level 3’ intensive care. METHODS Thirty-eight patients in sinus rhythm, ejection fraction ?35%, undergoing on-pump surgical revascularization, valve surgery or both were enrolled in this study. Before closing the sternum, temporary epicardial pacing wires were attached to the right atrium, RV outflow tract and basal posterolateral wall of the left ventricle. Patients were randomly assigned to postoperative BiV pacing with the optimization of the atrio- (AV) and inter-ventricular (VV) pacing intervals (Group 1) or conventional dual-chamber right AV pacing (Group 2). The primary end-point was the duration of ‘Level 3’ intensive care. Secondary end-points included cardiac output which was measured by thermodiluation at admission to the intensive care unit and at 6 and 18 h later, in five different pacing modes. RESULTS The duration of ‘Level 3’ care was similar between groups (40 ± 35 vs 54 ± 63 h; Group 1 vs 2; P = 0.43). Cardiac output was similar in all pacing modes at baseline. At 18 h, cardiac output with BiV pacing (5.8 l/min) was 7% higher than atrial inhibited (5.4 l/min) and 9% higher than dual-chamber RV pacing (5.3 l/min; P = 0.02 and 0.001, respectively). Optimization of the VV interval produced a further 4% increase in cardiac output compared with baseline settings (P = 0.005). CONCLUSIONS Postoperative haemodynamic function may be enhanced by temporary BiV pacing of high-risk patients after on-pump cardiac surgery.

Russell, Stuart J.; Tan, Christine; O'Keefe, Peter; Ashraf, Saeed; Zaidi, Afzal; Fraser, Alan G.; Yousef, Zaheer R.

2012-01-01

107

Pulmonary vein isolation under direct visual identification of the left atrium—pulmonary vein junction using intra-cardiac echography  

Microsoft Academic Search

Introduction: Intra-cardiac echocardiography (ICE) which has some benefits, can be used to obtain detailed anatomy of the heart chambers\\u000a or large vessels, and the catheter positions, and it has been considered useful for improving the outcome of the ablation.\\u000a In the present study, we performed pulmonary vein isolation (PVI) under real time monitoring of ICE imaging utilizing an ICE\\u000a catheter

Y. Higashi; H. Shimojima; D. Wakatsuki; K. Wakabayashi; F. Asano; Y. Honda; K. Kawachi; K. Oota; T. Sato; M. Ebato; T. Hashimoto; T. Takeshi; Y. Takeyama

2006-01-01

108

Usefulness of cardiac computed tomographic delayed contrast enhancement of the left atrial appendage before pulmonary vein ablation.  

PubMed

Left atrial appendage (LAA) contrast filling defects are commonly found in patients undergoing multidetector cardiac computed tomography (CCT) before catheter ablation of atrial fibrillation. Delayed CCT allows quantification of the LAA delayed/initial attenuation ratio and improves accuracy for LAA thrombus detection, which may obviate routine transesophageal echocardiography (TEE) before ablation. CCT with contrast-enhanced scans (initial CCT) and with noncontrast-enhanced scans (delayed CCT) was performed in 176 patients. LAA was evaluated for filling defects. LAA apex, left atrial (LA) body, and ascending aorta (AA) attenuations (Hounsfield units) were measured on initial and delayed cardiac computed tomograms to calculate LAA, LA, LAA/LA, and LAA/AA attenuation ratios. LAA, initial LAA/LA, and initial LAA/AA attenuation ratios differed significantly in patients with versus without filling defects on cardiac computed tomogram, those with atrial fibrillation versus normal sinus rhythm, and those with abnormal left ventricular ejection fraction versus larger LA volumes (p <0.05). In 70 patients (40%) who underwent TEE, 13 LAA filling defects were seen on initial cardiac computed tomogram. Two defects persisted on delayed cardiac computed tomogram and thrombus was confirmed on transesophageal echocardiogram. Sensitivity, specificity, and positive and negative predictive values of initial CCT for LAA thrombi detection were 100%, 84%, 15%, and 100%, respectively. With delayed CCT these values increased to 100%. Intraobserver and interobserver reproducibilities for cardiac computed tomographic measurements were good (intraclass correlation 0.72 to 0.97, kappa coefficients 0.93 to 1.00). In conclusion, delayed CCT provided an increase in diagnostic accuracy of CCT for detection of LAA thrombus in patients with atrial fibrillation before ablation, which may decrease the need for routine TEE before the procedure. PMID:22364703

Sawit, Simonette T; Garcia-Alvarez, Ana; Suri, Bhavna; Gaztanaga, Juan; Fernandez-Friera, Leticia; Mirelis, Jesus G; D'Anca, Michael; Fuster, Valentin; Sanz, Javier; Garcia, Mario J

2012-03-01

109

4-D Cardiac MR Image Analysis: Left and Right Ventricular Morphology and Function  

PubMed Central

In this study, a combination of active shape model (ASM) and active appearance model (AAM) was used to segment the left and right ventricles of normal and Tetralogy of Fallot (TOF) hearts on 4-D (3-D+time) MR images. For each ventricle, a 4-D model was first used to achieve robust preliminary segmentation on all cardiac phases simultaneously and a 3-D model was then applied to each phase to improve local accuracy while maintaining the overall robustness of the 4-D segmentation. On 25 normal and 25 TOF hearts, in comparison to the expert traced independent standard, our comprehensive performance assessment showed subvoxel segmentation accuracy, high overlap ratios, good ventricular volume correlations, and small percent volume differences. Following 4-D segmentation, novel quantitative shape and motion features were extracted using shape information, volume-time and dV/dt curves, analyzed and used for disease status classification. Automated discrimination between normal/TOF subjects achieved 90%–100% sensitivity and specificity. The features obtained from TOF hearts show higher variability compared to normal subjects, suggesting their potential use as disease progression indicators. The abnormal shape and motion variations of the TOF hearts were accurately captured by both the segmentation and feature characterization.

Wahle, Andreas; Johnson, Ryan K.; Scholz, Thomas D.; Sonka, Milan

2010-01-01

110

Primary cardiac plasmablastic (diffuse large B-cell) lymphoma mimicking left ventricular aneurysm with mural thrombus  

Microsoft Academic Search

Primary cardiac lymphoma is rare and is usually of the non-Hodgkin type. By definition, it involves only the heart and the pericardium, with no evidence of extracardiac disease. Primary cardiac lymphoma accounts for 1% of primary cardiac tumors and 0.5% of extranodal lymphomas [Gowda RM, Kahn RA. Clinical perspectives of primary cardiac lymphoma. Angiology 2003;54(5):599–604]. On the other hand, secondary

Dylan V. Miller; Farouk Mookadam; Martina Mookadam; William D. Edwards; William R. Macon

2007-01-01

111

Migration of left ventricular thrombus causing abdominal aortic embolism during cardiac surgery in a child with severe left ventricular dysfunction.  

PubMed

A 1-year-old girl with severe left ventricular dysfunction presented with large floating thrombi in the left ventricle. Surgical thrombectomy was urgently required. During cannulation, transesophageal echocardiogram detected that the thrombus had vanished from the left ventricle. Whole body angiogram under very low-flow cardiopulmonary bypass successfully obtained the exact site of embolization with reducing total amount of contrast media in the operating room. Consequently, under deep hypothermic circulatory arrest, the obstructive thrombi at the abdominal aorta were successfully removed using Fogarty catheters from ascending aortotomy. Although delayed sternal closure was postoperatively required, no complication including thromboembolic events were observed for a 1.5-year follow-up period. PMID:19240058

Nagashima, Mitsugi; Takano, Shinji; Yamamoto, Eiichi; Higaki, Takashi

2009-02-24

112

A novel technique for intraaortic balloon pump placement via the left axillary artery in patients awaiting cardiac transplantation.  

PubMed

In order to circumvent the problems associated with long-term femoral intraaortic balloon pump (IABP) placement we have developed and used a new technique of IABP placement. Over the past three years 13 patients awaiting cardiac transplantation have had placement of IABP via a vein cuff sewn to the left axillary artery. Thirteen patients have undergone IABP placement using this technique. The average duration of IABP support was 37 days (range 10-86 days). Ten patients were successfully transplanted. All patients were allowed to sit, stand and ambulate with assistance. No neurologic complications occurred. There were no episodes of sepsis related to balloon or insertion site. No patient had limb ischemia during IABP counterpulsation. Left axillary artery IABP insertion via a vein cuff portal is a straightforward technique with minimal complications. This method serves as a bridge to cardiac transplantation in a gravely ill group of patients while preserving patient mobility during the waiting period for a donor heart. PMID:10996101

H'Doubler, P B; H'Doubler, W Z; Bien, R C; Jansen, D A

2000-10-01

113

Rupture of a giant cardiac hydatid cyst in the left ventricular free wall: successful surgical management of a rare entity  

PubMed Central

Hydatid cyst of heart is a rare but potentially fatal site of pathology, especially left ventricular free wall. We managed a successful surgical treatment on a case of a 24 year old man who had a giant cardiac hydatid cyst (71 x 64 mm) that ruptured left ventricular free wall. The cyst was excised gently and all the cystic materials were removed, the cyst cavity was closed with GORE-TEX soft tissue patch. The patient was discharged on the 9th postoperative day without symptoms. This case is different from other cardiac hydatid cysts that have been reported in literature previously; because this patient was young and had advanced phase of the disease that presented to our clinic lately. Additionally, the cyst had limited both ventricular volumes significantly.

Hosseinian, Adallat; Mohammadzadeh, Alireza; Shahmohammadi, Ghader; Hasanpour, Mohammad; Maleki, Nasrollah; Doustkami, Hossein; Haghdoost, Zarafshan

2013-01-01

114

Association Between Tangential Beam Treatment Parameters and Cardiac Abnormalities After Definitive Radiation Treatment for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To examine the association between radiation treatment (RT) parameters, cardiac diagnostic test abnormalities, and clinical cardiovascular diagnoses among patients with left-sided breast cancer after breast conservation treatment with tangential beam RT. Methods and Materials: The medical records of 416 patients treated between 1977 and 1995 with RT for primary left-sided breast cancer were reviewed for myocardial perfusion imaging and echocardiograms. Sixty-two patients (62/416, 15%) underwent these cardiac diagnostic tests for cardiovascular symptoms and were selected for further study. Central lung distance and maximum heart width and length in the treatment field were determined for each patient. Medical records were reviewed for cardiovascular diagnoses and evaluation of cardiac risk factors. Results: At a median of 12 years post-RT the incidence of cardiac diagnostic test abnormalities among symptomatic left-sided irradiated women was significantly higher than the predicted incidence of cardiovascular disease in the patient population, 6/62 (9%) predicted vs. 24/62 (39%) observed, p 0.001. As compared with patients with normal tests, patients with cardiac diagnostic test abnormalities had a larger median central lung distance (2.6 cm vs. 2.2 cm, p = 0.01). Similarly, patients with vs. without congestive heart failure had a larger median central lung distance (2.8 cm vs. 2.3 cm, p = 0.008). Conclusions: Contemporary RT for early breast cancer may be associated with a small, but potentially avoidable, risk of cardiovascular morbidity that is associated with treatment technique.

Correa, Candace R. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Das, Indra J. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)], E-mail: Das@xrt.upenn.edu; Litt, Harold I. [Department of Radiology-Cardiovascular Imaging Section, University of Pennsylvania, Philadelphia, PA (United States); Ferrari, Victor [Department of Medicine-Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA (United States); Hwang, W.-T. [Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA (United States); Solin, Lawrence J.; Harris, Eleanor E. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)

2008-10-01

115

Development of a swine model of left bundle branch block for experimental studies of cardiac resynchronization therapy.  

PubMed

Animal models that mimic human electrical and mechanical dyssynchrony often associated with chronic heart failure would provide an essential tool to investigate factors influencing response to cardiac resynchronization therapy. A standardized closed-chest porcine model of left bundle branch block (LBBB) was developed using 16 pigs. Radiofrequency applications were performed to induce LBBB, which was confirmed by QRS widening, a surface electrocardiogram pattern concordant with LBBB, and a prolonged activation time from endocardial. Echocardiography confirmed abnormal motion of the septum, which was not present at the baseline echocardiogram. High susceptibility of pigs to ventricular fibrillation during the endocardial ablation was overcome by applying high-rate pacing during radiofrequency applications. This is the first study to devise a closed-chest porcine model of LBBB that closely reproduces abnormalities found in patients with electrical and mechanical cardiac dyssynchrony, and provides a useful tool to investigate the basic mechanisms underlying cardiac resynchronization therapy benefits in heart failure. PMID:23636845

Rigol, Montserrat; Solanes, Núria; Fernandez-Armenta, Juan; Silva, Etelvino; Doltra, Adelina; Duchateau, Nicolas; Barcelo, Aina; Gabrielli, Luigi; Bijnens, Bart; Berruezo, Antonio; Brugada, Josep; Sitges, Marta

2013-04-30

116

Assessment of Cardiac Structure and Left Atrial Appendage Functions in Primary Antiphospholipid Syndrome A Transesophageal Echocardiographic Study  

Microsoft Academic Search

Background and Purpose—Although thromboembolic events are the major complication of primary antiphospholipid syndrome (PAPS), cardiac involvement is commonly present. Left atrial appendage (LAA) is recognized as an important source for thrombus formation and thromboembolism. The purpose of the study was to assess the structure and function of LAA with transesophageal echocardiography (TEE) in PAPS patients. Methods—Thirty-one PAPS patients (22 women,

Dogan Erdogan; M. Taner Goren; Reyhan Diz-Kucukkaya; Murat Inanc

117

Using left-ventricular-only pacing to eliminate T-wave oversensing in a biventricular implantable cardiac defibrillator.  

PubMed

A man aged 75 years and with nonischemic cardiomyopathy had implantation of a biventricular implantable cardiac defibrillator (ICD). Consistent biventricular pacing was limited by intermittent T-wave oversensing (TWOS). A strategy of left-ventricular-only pacing was used to eliminate TWOS. This strategy obviates the need to reduce ventricular sensitivity and thus may be an effective alternative to biventricular pacing complicated by TWOS. PMID:22902157

Khoo, Clarence; Bennett, Matthew; Chakrabarti, Santabhanu; LeMaitre, John; Tung, Stanley K K

2012-08-15

118

Intraoperative Anticoagulation Management during Cardiac Transplantation for a Patient with Heparin-Induced Thrombocytopenia and a Left Ventricular Assist Device  

PubMed Central

Heparin-induced thrombocytopenia is an immunologically mediated syndrome that is associated with potentially life-threatening arterial and venous thrombosis. Re-exposing patients who have heparin-induced thrombocytopenia to heparin during cardiopulmonary bypass may be hazardous. We describe the re-exposure to unfractionated heparin of a patient with a left ventricular assist device and evidence of heparin-induced thrombocytopenia who needed cardiac transplantation, which was accomplished without complications.

Wadia, Yasmin; Cooper, John R.; Bracey, Arthur W.; Pinto, Katheleen; Frazier, O. H.

2008-01-01

119

Left atrial volume predicts adverse cardiac and cerebrovascular events in patients with hypertrophic cardiomyopathy  

PubMed Central

Aims To prospectively evaluate the relationship between left atrial volume (LAV) and the risk of clinical events in patients with hypertrophic cardiomyopathy (HCM). Methods We enrolled a total of 141 HCM patients with sinus rhythm and normal pump function, and 102 patients (73 men; mean age, 61 ± 13 years) who met inclusion criteria were followed for 30.8 ± 10.0 months. The patients were divided into two groups with or without major adverse cardiac and cerebrovascular events (MACCE), a composite of stroke, sudden death, and congestive heart failure. Detailed clinical and echocardiographic data were obtained. Results MACCE occurred in 24 patients (18 strokes, 4 congestive heart failure and 2 sudden deaths). Maximum LAV, minimum LAV, and LAV index (LAVI) corrected for body surface area (BSA) were significantly greater in patients with MACCE than those without MACCE (maximum LAV: 64.3 ± 25.0 vs. 51.9 ± 16.0 ml, p = 0.005; minimum LAV: 33.9 ± 15.1 vs. 26.2 ± 10.9 ml, p = 0.008; LAVI: 40.1 ± 15.4 vs. 31.5 ± 8.7 ml/mm2, p = 0.0009), while there were no differences in the other echocardiographic parameters. LAV/BSA of ? 40.4 ml/m2 to identify patients with cardiovascular complications with a sensitivity of 73% and a specificity of 88%. Conclusion LAVI may be an effective marker for detecting the risk of MACCE in patients with HCM and normal pump function.

2011-01-01

120

Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears.  

PubMed

Grizzly bears (Ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. Left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. We evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (MyHC) isoform expression and expression of a set of genes important to muscle plasticity and mass regulation in the left atria and left ventricles of active and hibernating bears. We supplemented these data with measurements of systolic and diastolic function via echocardiography in unanesthetized grizzly bears. Atrial strain imaging revealed decreased atrial contractility, decreased expansion/reservoir function (increased atrial stiffness), and decreased passive-filling function (increased ventricular stiffness) in hibernating bears. Relative MyHC-? protein expression increased significantly in the atrium during hibernation. The left ventricle expressed 100% MyHC-? protein in both groups. Insulin-like growth factor (IGF-I) mRNA expression was reduced by ?50% in both chambers during hibernation, consistent with the ventricular atrophy observed in these bears. Interestingly, mRNA expression of the atrophy-related ubiquitin ligases Muscle Atrophy F-box (MAFBx) and Muscle Ring Finger 1 did not increase, nor did expression of myostatin or hypoxia-inducible factor 1? (HIF-1?). We report atrium-specific decreases of 40% and 50%, respectively, in MAFBx and creatine kinase mRNA expression during hibernation. Decreased creatine kinase expression is consistent with lowered energy requirements and could relate to reduced atrial emptying function during hibernation. Taken together with our hemodynamic assessment, these data suggest a potential downregulation of atrial chamber function during hibernation to prevent fatigue and dilation due to excessive work against an optimally filled ventricle, a response unpredicted by the Frank-Starling mechanism. PMID:21117961

Barrows, N D; Nelson, O L; Robbins, C T; Rourke, B C

121

Alterations in myostatin expression are associated with changes in cardiac left ventricular mass but not ejection fraction in the mouse.  

PubMed

Myostatin (Mst) is a negative regulator of skeletal muscle in humans and animals. It is moderately expressed in the heart of sheep and cattle, increasing considerably after infarction. Genetic blockade of Mst expression increases cardiomyocyte growth. We determined whether Mst overexpression in the heart of transgenic mice reduces left ventricular size and function, and inhibits in vitro cardiomyocyte proliferation. Young transgenic mice overexpressing Mst in the heart (Mst transgenic mice (TG) under a muscle creatine kinase (MCK) promoter active in cardiac and skeletal muscle, and Mst knockout (Mst (-/-)) mice were used. Xiscan angiography revealed that the left ventricular ejection fraction did not differ between the Mst TG and the Mst (-/-) mice, when compared with their respective wild-type strains, despite the decrease in whole heart and left ventricular size in Mst TG mice, and their increase in Mst (-/-) animals. The expected changes in cardiac Mst were measured by RT-PCR and western blot. Mst and its receptor (ActRIIb) were detected by RT-PCR in rat H9c2 cardiomyocytes. Transfection of H9c2 with plasmids expressing Mst under muscle-specific creatine kinase promoter, or cytomegalovirus promoter, enhanced p21 and reduced cdk2 expression, when assessed by western blot. A decrease in cell number occurred by incubation with recombinant Mst (formazan assay), without affecting apoptosis or cardiomyocyte size. Anti-Mst antibody increased cardiomyocyte replication, whereas transfection with the Mst-expressing plasmids inhibited it. In conclusion, Mst does not affect cardiac systolic function in mice overexpressing or lacking the active protein, but it reduces cardiac mass and cardiomyocyte proliferation. PMID:17592022

Artaza, Jorge N; Reisz-Porszasz, Suzanne; Dow, Joan S; Kloner, Robert A; Tsao, James; Bhasin, Shalender; Gonzalez-Cadavid, Nestor F

2007-07-01

122

Hybrid segmentation of left ventricle in cardiac MRI using Gaussian-mixture model and region restricted dynamic programming.  

PubMed

Segmentation of the left ventricle from cardiac magnetic resonance images (MRI) is very important to quantitatively analyze global and regional cardiac function. The aim of this study is to develop a novel and robust algorithm which can improve the accuracy of automatic left ventricle segmentation on short-axis cardiac MRI. The database used in this study consists of three data sets obtained from the Sunnybrook Health Sciences Centre. Each data set contains 15 cases (4 ischemic heart failures, 4 non-ischemic heart failures, 4 left ventricle (LV) hypertrophies and 3 normal cases). Three key techniques are developed in this segmentation algorithm: (1) ray scanning approach is designed for segmentation of images with left ventricular outflow tract (LVOT), (2) a region restricted technique is employed for epicardial contour extraction, and (3) an edge map with non-maxima gradient suppression approach is put forward to improve the dynamic programming to derive the epicardial boundary. The validation experiments were performed on a pool of data sets of 45 cases. For both endo- and epi-cardial contours of our results, percentage of good contours is about 91%, the average perpendicular distance is about 2mm. The overlapping dice metric is about 0.92. The regression and determination coefficient between the experts and our proposed method on the ejection fraction (EF) is 1.01 and 0.9375, respectively; they are 0.9 and 0.8245 for LV mass. The proposed segmentation method shows the better performance and is very promising in improving the accuracy of computer-aided diagnosis systems in cardiovascular diseases. PMID:23245907

Hu, Huaifei; Liu, Haihua; Gao, Zhiyong; Huang, Lu

2012-12-14

123

The uncalibrated pulse contour cardiac output during off-pump coronary bypass surgery: performance in patients with a low cardiac output status and a reduced left ventricular function  

PubMed Central

Background We compared the continuous cardiac index measured by the FloTrac/Vigileo™ system (FCI) to that measured by a pulmonary artery catheter (CCI) with emphasis on the accuracy of the FCI in patients with a decreased left ventricular ejection fraction (LVEF) and a low cardiac output status during off-pump coronary bypass surgery (OPCAB). We also assessed the influence of several factors affecting the pulse contour, such as the mean arterial pressure (MAP), the systemic vascular resistance index (SVRI) and the use of norepinephrine. Methods Fifty patients who were undergoing OPCAB (30 patients with a LVEF ? 40%, 20 patients with a LVEF < 40%) were enrolled. The FCI and CCI were measured and we performed a Bland-Altman analysis. Subgroup analyses were done according to the LVEF (< 40%), the CCI (? 2.4 L/min/m), the MAP (60-80 mmHg), the SVRI (1,600-2,600 dyne/s/cm5/m2) and the use of norepinephrine. Results The FCI was reliable at all the time points of measurement with an overall bias and limit of agreement of -0.07 and 0.67 L/min/m2, respectively, resulting in a percentage error of 26.9%. The percentage errors in the patients with a decreased LVEF and in a low cardiac output status were 28.2% and 22.3%, respectively. However, the percentage error in the 91 data pairs outside the normal range of the SVRI was 40.2%. Conclusions The cardiac output measured by the FloTrac/Vigileo™ system was reliable even in patients with a decreased LVEF and in a low cardiac output status during OPCAB. Acceptable agreement was also noted during the period of heart displacement and grafting of the obtuse marginalis branch.

Jo, Youn Yi; Song, Jong Wook; Yoo, Young Chul; Park, Ji Young; Kwak, Young Lan

2011-01-01

124

The cardiac renin-angiotensin system is responsible for high-salt diet-induced left ventricular hypertrophy in mice  

PubMed Central

Aims This study aimed to determine the role of the renin-angiotensin system (RAS) in high salt (HS) diet-induced left ventricular hypertrophy (LVH). Methods and Results Swiss mice were subjected to regular salt (RS) diet (0.6% NaCl), HS diet (4% NaCl) and HS plus irbesartan (50 mg/kg/day) or ramipril (1 mg/kg/day). After 8 weeks, arterial pressure was similar in all groups and similar to baseline, whereas LV/body weight ratio was higher in HS mice than in RS mice (p<0.005). There were also significant increases in collagen density, ACE activity, AT1 receptor density and extracellular signal-regulated kinase (ERK1/2) phosphorylation in the left ventricle. Interestingly, increases in wall thickness and ERK1 phosphorylation were more marked in the septum than in the rest of the left ventricle. Irbesartan or ramipril treatment prevented LVH and the increase in ERK phosphorylation and reduced collagen content and AT1 upregulation but upregulated AT2 receptors. Conclusions In normal mice, HS diet induces septum-predominant LVH and fibrosis through activation of the cardiac RAS-ERK pathway, which can be blocked by irbesartan or ramipril, indicating a key role of the cardiac RAS in HS diet-induced LVH.

Le Corvoisier, Philippe; Adamy, Christophe; Sambin, Lucien; Crozatier, Bertrand; Berdeaux, Alain; Michel, Jean-Baptiste; Hittinger, Luc; Su, Jinbo

2010-01-01

125

Post-traumatic left ventricular pseudoaneurysm  

PubMed Central

Left ventricular pseudoaneurysms (LVPs) occur as a complication of myocardial infarction, cardiac surgery and, rarely, due to thoracic trauma, infective pericarditis or iatrogenisis due to accidental perforation of the myocardium. Ventricular pseudoaneurysms are acquired by blood-filled spaces outside the cardiac chambers communicating with the ventricle. We present a case of LVP presented after a blunt non-penetrating chest injury. The patient underwent successful aneurysmorrhaphy.

Singh, Sushil; Puri, Aniket; Narain, Varun; Sahni, Jeevan

2012-01-01

126

Monitoring effects of ?-human atrial natriuretic polypeptide (?-hANP) on left ventricular function in patients with essential hypertension with a cardiac probe  

Microsoft Academic Search

The effects of a-hANP on left ventricular function were studied with a cardiac probe in ten patients with essential hypertension. Our data showed that intravenous administration of a-hANP significantly elevated left ventricular function. At 5 min, the elevation of EF, RCO, ER, RSV, PFR were 13.23% (PPPPPPPP<0.001–0.05).

Xiu-jie Liu; Yun-zhong Liu; Zuo-xiang He; Bao-guei Zhou; Li-sheng Liu; Henry N. Wagner

1987-01-01

127

Is Magnetic Resonance Imaging the 'Reference Standard' for Cardiac Functional Assessment? Factors Influencing Measurement of Left Ventricular Mass and Volumes  

Microsoft Academic Search

Purpose\\u000a   MRI is considered\\u000a reference standard for the\\u000a assessment of left ventricular (LV)\\u000a volume and mass measurements.\\u000a There are few accepted guidelines\\u000a for uniform assessment of cardiac\\u000a function with MRI. We sought to\\u000a investigate different confounding\\u000a factors influencing LV measurement\\u000a results.\\u000a \\u000a \\u000a \\u000a \\u000a Material and Methods\\u000a   In 60 diabetic type-II patients\\u000a (group A) we compared intra-\\/inter-reader variability of MRI for\\u000a cardiac function

Henning Steen; Khurram Nasir; Ellen Flynn; Iman El-Shehaby; Shenghan Lai; Hugo A. Katus; David Bluemcke; João A. C. Lima

2007-01-01

128

Transatrial access for left atrial pressure monitoring in cardiac surgery patients  

Microsoft Academic Search

We describe a simple method for left atrial pressure (LAP) monitoring from the right to the left atrium (LA) by a central line catheter. The anesthesiologist cannulates vena jugularis interna and inserts two central line catheters. One catheter is placed in the vena cava superior and the second single-lumen catheter is placed in the right atrium. The surgeon positions a

Roman Zahorec; Marian Holoman

1997-01-01

129

Restored cardiac conditions and left ventricular function after parathyroidectomy in a hemodialysis patient. Parathyroidectomy improves cardiac fatty acid metabolism assessed by 123I-BMIPP.  

PubMed

A 62 year-old female hemodialysis patient underwent parathyroidectomy to treat secondary hyperparathyroidism. On the preoperative assessment, the plasma levels of parathyroid hormone (PTH) and B-type natriuretic peptide (BNP) were elevated. Echocardiography showed reduced left ventricular (LV) contraction. Myocardial iodine-123-15-(p-iodophenyl)-3-(R,S) methylpentadecanoic acid ((123)I-BMIPP) scintigraphy showed moderately reduced tracer uptake in the postero-inferior area on single-photon emission computed tomography and decreased washout on the planar images. After parathyroidectomy, the plasma levels of PTH and BNP decreased, followed by improvement in LV contraction. Myocardial (123)I-BMIPP scintigraphy revealed that the washout on planar images had increased, which suggests that myocardial (123)I-BMIPP scintigraphy is useful for estimating the effect of parathyroidectomy on cardiac function. PMID:19179778

Nanasato, Mamoru; Goto, Norihiko; Isobe, Satoshi; Unno, Kazumasa; Hirayama, Haruo; Sato, Tetsuhiko; Matsuoka, Susumu; Nagasaka, Takaharu; Tominaga, Yoshihiro; Uchida, Kazuharu; Murohara, Toyoaki

2009-01-27

130

Segmentation of the Left Ventricle from Cardiac MR Images Using a Subject-Specific Dynamical Model  

PubMed Central

Statistical models have shown considerable promise as a basis for segmenting and interpreting cardiac images. While a variety of statistical models have been proposed to improve the segmentation results, most of them are either static models (SM),which neglect the temporal dynamics of a cardiac sequence or generic dynamical models (GDM), which are homogeneous in time and neglect the inter-subject variability in cardiac shape and deformation. In this paper, we develop a subject-specific dynamical model (SSDM) that simultaneously handles temporal dynamics (intra-subject variability) and inter-subject variability. We also propose a dynamic prediction algorithm that can progressively identify the specific motion patterns of a new cardiac sequence based on the shapes observed in past frames. The incorporation of this SSDM into the segmentation framework is formulated in a recursive Bayesian framework. It starts with a manual segmentation of the first frame, and then segments each frame according to intensity information from the current frame as well as the prediction from past frames. In addition, to reduce error propagation in sequential segmentation, we take into account the periodic nature of cardiac motion and perform segmentation in both forward and backward directions. We perform “Leave-one-out” test on 32 canine sequences and 22 human sequences, and compare the experimental results with those from SM, GDM, and Active Appearance Motion Model (AAMM). Quantitative analysis of the experimental results shows that SSDM outperforms SM, GDM, and AAMM by having better global and local consistencies with manual segmentation. Moreover, we compare the segmentation results from forward and forward-backward segmentation. Quantitative evaluation shows that forward-backward segmentation suppresses the propagation of segmentation errors.

Zhu, Yun; Papademetris, Xenophon; Sinusas, Albert J.; Duncan, James S.

2009-01-01

131

Cardiac remodeling and angiotensin II-forming enzyme activity of the left ventricle in hamsters with chronic pressure overload induced by ascending aortic stenosis.  

PubMed

Cardiac remodeling and angiotensin II-forming enzyme activity of the left ventricle on chronic pressure overload were studied in male Syrian hamsters, whose chymase activity is similar to that of dogs. Pressure overload was achieved by banding at the ascending aorta (aortic stenosis). Echocardiography, histological analysis, and analysis of cardiac angiotensin-converting enzyme and chymase-like activities were performed. At 10 weeks after banding, concentric hypertrophy of the left ventricle was evident. At 20 weeks after banding, the ventricular weight-to-body ratio, cardiac fibrosis, and cardiac chymase-like activity were significantly increased, while cardiac angiotensin-converting enzyme activity was significantly decreased. This suggests that cardiac chymase, compared with cardiac angiotensin-converting enzyme, was activated against the chronic pressure overload and was responsible for the cardiac remodeling through the formation of angiotensin II. Considering the utility of the rodents, the interspecies similarity of the Ang II-forming pathway, and the effect of chymase in the hamsters, the present model is considered useful for studies evaluating the effect of Ang II and chymase in the canine heart with chronic pressure overload. PMID:16598172

Shimizu, Miki; Tanaka, Ryou; Fukuyama, Tomoki; Aoki, Ryoko; Orito, Kensuke; Yamane, Yoshihisa

2006-03-01

132

Cardiac-specific Overexpression of Calsequestrin Results in Left Ventricular Hypertrophy, Depressed Force–frequency Relation and Pulsus Alternans In Vivo  

Microsoft Academic Search

A. G. Schmidt, V. J. Kadambi, N. Ball, Y. Sato, R. A. Walsh, E. G. Kranias and B. D. Hoit. Cardiac-specific Overexpression of Calsequestrin Results in Left Ventricular Hypertrophy, Depressed Force–frequency Relation and Pulsus Alternans In Vivo.Journal of Molecular and Cellular Cardiology (2000) 32, 1735–1744. Cardiac-specific overexpression of calsequestrin has been shown to result in significant decreases in contractile parameters

Albrecht G Schmidt; Vivek J Kadambi; Nancy Ball; Yoji Sato; Richard A Walsh; Evangelia G Kranias; Brian D Hoit

2000-01-01

133

Surgical removal of right-to-left cardiac shunt in the American alligator (Alligator mississippiensis) causes ventricular enlargement but does not alter apnoea or metabolism during diving  

Microsoft Academic Search

SUMMARY Crocodilians have complete anatomical separation between the ventricles, similar to birds and mammals, but retain the dual aortic arch system found in all non-avian reptiles. This cardiac anatomy allows surgical modification that prevents right-to-left (R-L) cardiac shunt. A R-L shunt is a bypass of the pulmonary circulation and recirculation of oxygen-poor blood back to the systemic circulation and has

John Eme; June Gwalthney; Jason M. Blank; Tomasz Owerkowicz; Gildardo Barron; James W. Hicks

2009-01-01

134

Validation of transcatheter left ventricular electromechanical mapping for assessment of cardiac function and targeted transendocardial injection in a porcine ischemia-reperfusion model  

PubMed Central

Ischemic heart disease, despite advances in treatment, remains the major cause of mortality worldwide. NOGA 3D left ventricular electromechanical mapping allows accurate determination of cardiac function and precise identification of sites of injury. In a porcine model of ischemia-reperfusion injury, we validate the use of the NOGA mapping system for assessment of cardiac function along with the Myostar injection catheter for directed delivery of therapeutics to localized target sites in the setting of acute myocardial injury.

Taghavi, Sharven; Duran, Jason M; Berretta, Remus M; Makarewich, Catherine A; Udeshi, Foram; Sharp, Thomas E; Kubo, Hajime; Houser, Steven R; George, Jon C

2012-01-01

135

Validation of transcatheter left ventricular electromechanical mapping for assessment of cardiac function and targeted transendocardial injection in a porcine ischemia-reperfusion model.  

PubMed

Ischemic heart disease, despite advances in treatment, remains the major cause of mortality worldwide. NOGA 3D left ventricular electromechanical mapping allows accurate determination of cardiac function and precise identification of sites of injury. In a porcine model of ischemia-reperfusion injury, we validate the use of the NOGA mapping system for assessment of cardiac function along with the Myostar injection catheter for directed delivery of therapeutics to localized target sites in the setting of acute myocardial injury. PMID:22611476

Taghavi, Sharven; Duran, Jason M; Berretta, Remus M; Makarewich, Catherine A; Udeshi, Foram; Sharp, Thomas E; Kubo, Hajime; Houser, Steven R; George, Jon C

2012-04-18

136

Isolated Non-Compaction of the Left Ventricle in a Patient with New-Onset Heart Failure: Morphologic and Functional Evaluation with Cardiac Multidetector Computed Tomography  

PubMed Central

We describe a case of new-onset heart failure in a patient in whom cardiac CT enabled the non-invasive diagnosis of isolated non-compaction and associated functional abnormalities of the left ventricle with the concomitant evaluation of coronary arteries. This case highlights the utility of cardiac CT for the morphological and functional evaluation of the heart as a single imaging modality.

Lee, Heon; Kim, Seok-Yeon

2012-01-01

137

Isolated non-compaction of the left ventricle in a patient with new-onset heart failure: morphologic and functional evaluation with cardiac multidetector computed tomography.  

PubMed

We describe a case of new-onset heart failure in a patient in whom cardiac CT enabled the non-invasive diagnosis of isolated non-compaction and associated functional abnormalities of the left ventricle with the concomitant evaluation of coronary arteries. This case highlights the utility of cardiac CT for the morphological and functional evaluation of the heart as a single imaging modality. PMID:22438694

Lee, Heon; Kim, Seok-Yeon; Schoepf, U Joseph

2012-03-07

138

Unsupervised reconstruction of a three-dimensional left ventricular strain from parallel tagged cardiac images.  

PubMed

A new algorithm, called the Unsupervised Tag ExTraction and Heart strain(E) Reconstruction (UNTETHER) algorithm, is presented for quantifying three-dimensional (3D) myocardial strain in tagged cardiac MR images. Five human volunteers and five postinfarct patients were imaged. 3D strains measured by UNTETHER and a user-supervised technique were compared. Each study was analyzed in 49 +/- 8 min with UNTETHER, compared to approximately 4 hr with the user-supervised technique. For pooled human data, the correlation coefficient between the two methods for circumferential shortening (E(cc)) was r = 0.91 at the mid-wall (P < 0.0005). UNTETHER is capable of measuring wall motion abnormalities resulting from coronary artery disease, and has the potential to overcome the main limitations (time and user-supervision requirements) to routine clinical use of tagged cardiac MRI. PMID:12652546

Denney, Thomas S; Gerber, Bernhard L; Yan, Litao

2003-04-01

139

Left Ventricular Remodeling in Transgenic Mice With Cardiac Restricted Overexpression of Tumor Necrosis Factor  

Microsoft Academic Search

Background—The mechanisms responsible for tumor necrosis factor (TNF)-induced LV structural remodeling in the adult heart are not known. Methods and Results—We generated a line of transgenic mice (MHCsTNF) with cardiac restricted overexpression of TNF that develop progressive LV dilation\\/remodeling from 4 to 12 weeks of age. During the early phases of LV structural remodeling, there was a significant increase in

Natarajan Sivasubramanian; Mytsi L. Coker; Karla M. Kurrelmeyer; William R. MacLellan; Francesco J. DeMayo; Francis G. Spinale; Douglas L. Mann

2010-01-01

140

Enhanced intra-aortic balloon pump: markedly improved systemic hemodynamics and cardiac function in canines with severe, acute left ventricular failure.  

PubMed

Intra-aortic balloon pumps (IABPs) cannot sustain hemodynamics if the left heart is severely injured. An enhanced IABP was evaluated in 6 anesthetized dogs with acute stenosis of the left anterior descending coronary artery, regional left ventricular (LV) stunning, and global LV dysfunction. An IABP balloon was inserted into the descending aorta and an external chamber containing another IABP balloon was connected to the aorta through a catheter inserted into the left subclavian artery. This emulated the enhanced IABP with a conduit from its external chamber passing axially through an internal IABP balloon. Compared to IABP, enhanced IABP improved hemodynamics and LV function in all conditions. During severe LV dysfunction and circulatory failure, IABP failed to augment diastolic aortic pressure or improve coronary and carotid flows. Enhanced IABP augmented diastolic pressure from 32 +/- 3 mm Hg to 87 +/- 2 mm Hg and increased coronary and carotid flows. Enhanced IABP may be a lifesaving device for patients with severe LV failure. PMID:12139502

Bian, Xiaoming; Downey, H Fred

2002-08-01

141

"Cardiac incidentaloma": Left ventricular non-compaction in a kindred with familial coronary artery disease.  

PubMed

Whether to a greater or lesser extent, genetics often plays an important role in the development of cardiovascular diseases. Here we report a newly identified family with familial coronary artery disease (CAD) and left ventricular non-compaction (LVNC). A 52-year-old male with acute coronary syndrome, in whom LVNC had been found "incidentally", was admitted for revascularisation. From a two-dimensional echocardiogram the epicardial layer appeared to be thin and compacted, but the apical endocardial layer of the left ventricle was extremely thickened with prominent trabeculations in the endocardial layer and deep intertrabecular recesses in a channel-like structure. Family history revealed that his 47-year-old brother also had LVNC but to a lesser degree. Their mother had two false tendons in the left ventricular apex and both parents had severe CAD. Left ventricular non-compaction is "incidentally" identified in a kindred with familial CAD. The disease expressivity varies among affected individuals. Whether it is coincidental or there is a genetic link is a question that awaits further investigation. (Cardiol J 2007; 14: 407-410). PMID:18651493

Martini, D Bortolo; Sperotto, Claudio; Zhang, Li

2007-01-01

142

Regional Patterns of Left Ventricular Systolic Dysfunction After Subarachnoid Hemorrhage: Evidence for Neurally Mediated Cardiac Injury  

Microsoft Academic Search

Although left ventricular (LV) dysfunction has been described after subarachnoid hemorrhage (SAH), its pathophysiology, regional distribution, and reversibility remain uncertain. To test the hypothesis that regional wall motion patterns in SAH patients do not match the typical patterns observed in coronary artery disease, a segmental wall motion analysis was performed in 30 SAH patients with LV dysfunction. Both regional (n

Jonathan G Zaroff; Guy A Rordorf; Christopher S Ogilvy; Michael H Picard

2000-01-01

143

Baseline tissue Doppler imaging-derived echocardiographic parameters and left ventricle reverse remodelling following cardiac resynchronization therapy introduction  

PubMed Central

Introduction The aim of the study was to assess the relation of baseline mechanical dyssynchrony with the left ventricular end-systolic volume (LVESV) decrease following cardiac resynchronization (CRT) therapy introduction. Material and methods Sixty consecutive patients (aged 66.3 ± 8.7 years; 57 men) with chronic heart failure (71.7% of ischaemic and 28.3% of non-ischaemic origin) and current indications for CRT were assessed before and 3 months after biventricular heart stimulator implantation. Longitudinal movements of twelve segments of the left ventricle (LV) (6 basal and 6 midlevel) and two segments of the right ventricle (RV) were analysed using tissue Doppler imaging (TDI) techniques with time from onset of Q wave in ECG to peak systolic velocity in colour-coded TDI (TTDI), time to peak strain (Tstrain) and time to peak strain rate (Tstrain rate). Minimal and maximal time differences within LV and between LV and RV walls were calculated. Results In the study group LVEF and 6-min walk test distance increased, while NYHA class, NT-proBNP level, left ventricular end-diastolic volume and LVESV decreased. Significant correlations between the magnitude of LVESV reduction with maximal time differences between Tstrain of 12 LV segments (r=0.34, p = 0.017) and time differences between TTDI basal LV-RV segments (r = –0.29, p=0.041) were found. Conclusions Only a few TDI-derived parameters such as maximal time differences between Tstrain of 12 LV segments and TTDI difference of LV-RV basal segments can be useful to predict the magnitude of left ventricle reverse remodelling after CRT introduction.

Wilinski, Jerzy; Czarnecka, Danuta; Wojciechowska, Wiktoria; Kloch-Badelek, Malgorzata; Jastrzebski, Marek; Bacior, Bogumila; Sondej, Tomasz; Kusiak, Aleksander

2011-01-01

144

Left ventricular pressure measurement by telemetry is an effective means to evaluate transplanted heart function in experimental heterotopic cardiac xenotransplantation.  

PubMed

Evaluation of the function of heterotopic cardiac transplants has traditionally been accomplished by either manual palpation or serial biopsies. Both methods have drawbacks. Palpation can be difficult to differentiate a pulse from the graft versus a transmitted pulse from the native aorta. Serial biopsies, though accurate, require multiple laparotomies, leading to increased morbidity and possibly mortality rates. In this study we used an advanced telemetry system, consisting of an intra-abdominal implant, that was capable of continuously monitoring simultaneously several parameters of the transplanted heart and the status of the recipient. In a large animal model of heterotopic cardiac xenotransplantation (pig donor to baboon recipient), we implanted the device in 12 animals: 8 with and 4 without immunosuppression. We monitored and continuously recorded the left ventricular pressure (both peak-systolic and end-diastolic [LVEDP]), heart rate, and the electrocardiogram pattern of the transplanted heart as well as the temperature of the recipient. The left ventricular pressure proved to be the most valuable parameter to assess graft heart function. In the 4 nonimmunosuppressed cases, grafts were rejected acutely. In these cases, the end-diastolic pressure increased sharply and the heart stopped contracting when the difference between the systolic and the diastolic pressure decreased to <10 mm Hg. The earliest reproducible sign of rejection was an increased LVEDP. Among long-term survivors, the increase in diastolic pressure was gradual, indicating progressive thickening of the myocardium and decreased compliance of the ventricle. Six of 8 immunosuppressed animals died of other complications before rejecting the transplanted heart. The telemetry was also helpful to indicate early onset of fever in the recipients, thus allowing us to intervene early and prevent potentially lethal septic complications. Continuous monitoring of several parameters via telemetry allowed detection of changes associated with rejection as well as other complications at an early stage, allowing prompt intervention, treatment, and possibly reversal of rejection. PMID:20692431

Horvath, K A; Corcoran, P C; Singh, A K; Hoyt, R F; Carrier, C; Thomas, M L; Mohiuddin, M M

145

Computational modeling of volumetric soft tissue growth: application to the cardiac left ventricle.  

PubMed

As an initial step to investigate stimulus-response relations in growth and remodeling (G&R) of cardiac tissue, this study aims to develop a method to simulate 3D-inhomogeneous volumetric growth. Growth is regarded as a deformation that is decomposed into a plastic component which describes unconstrained growth and an elastic component to satisfy continuity of the tissue after growth. In current growth models, a single reference configuration is used that remains fixed throughout the entire growth process. However, considering continuous turnover to occur together with growth, such a fixed reference is unlikely to exist in reality. Therefore, we investigated the effect of tissue turnover on growth by incrementally updating the reference configuration. With both a fixed reference and an updated reference, strain-induced cardiac growth in magnitude of 30% could be simulated. However, with an updated reference, the amplitude of the stimulus for growth decreased over time, whereas with a fixed reference this amplitude increased. We conclude that, when modeling volumetric growth, the choice of the reference configuration is of great importance for the computed growth. PMID:18758835

Kroon, Wilco; Delhaas, Tammo; Arts, Theo; Bovendeerd, Peter

2008-08-30

146

Improved relationship between left and right ventricular electrical activation after cardiac resynchronization therapy in heart failure patients can be quantified by body surface potential mapping  

PubMed Central

OBJECTIVES: Few studies have evaluated cardiac electrical activation dynamics after cardiac resynchronization therapy. Although this procedure reduces morbidity and mortality in heart failure patients, many approaches attempting to identify the responders have shown that 30% of patients do not attain clinical or functional improvement. This study sought to quantify and characterize the effect of resynchronization therapy on the ventricular electrical activation of patients using body surface potential mapping, a noninvasive tool. METHODS: This retrospective study included 91 resynchronization patients with a mean age of 61 years, left ventricle ejection fraction of 28%, mean QRS duration of 182 ms, and functional class III/IV (78%/22%); the patients underwent 87-lead body surface mapping with the resynchronization device on and off. Thirty-six patients were excluded. Body surface isochronal maps produced 87 maximal/mean global ventricular activation times with three regions identified. The regional activation times for right and left ventricles and their inter-regional right-to-left ventricle gradients were calculated from these results and analyzed. The Mann-Whitney U-test and Kruskall-Wallis test were used for comparisons, with the level of significance set at p?0.05. RESULTS: During intrinsic rhythms, regional ventricular activation times were significantly different (54.5 ms vs. 95.9 ms in the right and left ventricle regions, respectively). Regarding cardiac resynchronization, the maximal global value was significantly reduced (138 ms to 131 ms), and a downward variation of 19.4% in regional-left and an upward variation of 44.8% in regional-right ventricular activation times resulted in a significantly reduced inter-regional gradient (43.8 ms to 17 ms). CONCLUSIONS: Body surface potential mapping in resynchronization patients yielded electrical ventricular activation times for two cardiac regions with significantly decreased global and regional-left values but significantly increased regional-right values, thus showing an attenuated inter-regional gradient after the cardiac resynchronization therapy.

Samesima, Nelson; Pastore, Carlos Alberto; Douglas, Roberto Andres; Filho, Martino Martinelli; Pedrosa, Anisio A.

2013-01-01

147

Pattern geometrici e funzione cardiaca in soggetti con insufficienza renale cronica in fase dialitica Left ventricular geometric patterns and cardiac function in patients with chronic renal failure undergoing hemodialysis  

Microsoft Academic Search

Left ventricular geometric patterns and cardiac function in patients with chronic renal failure undergoing hemodialysis. M.T. Manes, M. Gagliardi, G. Misuraca, S. Rossi, M. Chiatto. The aim of this study was to estimate the impact and prevalence of left ventricular geometric alterations and sys- tolic and diastolic dysfunction in hemodialysis patients, as well as the relationship with cardiac troponin as

Maria Teresa Manes; Manlio Gagliardi; Gianfranco Misuraca; Stefania Rossi; Mario Chiatto

148

Echocardiographic Assessment of Cardiac Involvement in Patients with Thalassemia Major: Evidence of Abnormal Relaxation Pattern of the Left Ventricle in Children and Young Patients  

Microsoft Academic Search

Background- Cardiac involvement which leads to congestive heart failure (CHF) is a major cause of death in patients with thalassemia major due to hemosiderosis and chronic anemia. Although the left ventricular (LV) systolic function in patients with thalassemia major has been considerably studied, LV diastolic function has not been assessed adequately. In this current study we used Doppler echocardiography to

A. Shahmohammadi; P. N. Davari; Y. Aarabi; M. Meraji; A. Tabib; H. Mortezaeian

149

Differences in cardiac microcirculatory wave patterns between the proximal left mainstem and proximal right coronary artery  

PubMed Central

Despite having almost identical origins and similar perfusion pressures, the flow-velocity waveforms in the left and right coronary arteries are strikingly different. We hypothesized that pressure differences originating from the distal (microcirculatory) bed would account for the differences in the flow-velocity waveform. We used wave intensity analysis to separate and quantify proximal- and distal-originating pressures to study the differences in velocity waveforms. In 20 subjects with unobstructed coronary arteries, sensor-tipped intra-arterial wires were used to measure simultaneous pressure and Doppler velocity in the proximal left main stem (LMS) and proximal right coronary artery (RCA). Proximal- and distal-originating waves were separated using wave intensity analysis, and differences in waves were examined in relation to structural and anatomic differences between the two arteries. Diastolic flow velocity was lower in the RCA than in the LMS (35.1 ± 21.4 vs. 56.4 ± 32.5 cm/s, P < 0.002), and, consequently, the diastolic-to-systolic ratio of peak flow velocity in the RCA was significantly less than in the LMS (1.00 ± 0.32 vs. 1.79 ± 0.48, P < 0.001). This was due to a lower distal-originating suction wave (8.2 ± 6.6 × 103 vs. 16.0 ± 12.2 × 103 W·m?2·s?1, P < 0.01). The suction wave in the LMS correlated positively with left ventricular pressure (r = 0.6, P < 0.01) and in the RCA with estimated right ventricular systolic pressure (r = 0.7, P = 0.05) but not with the respective diameter in these arteries. In contrast to the LMS, where coronary flow velocity was predominantly diastolic, in the proximal RCA coronary flow velocity was similar in systole and diastole. This difference was due to a smaller distal-originating suction wave in the RCA, which can be explained by differences in elastance and pressure generated between right and left ventricles.

Hadjiloizou, Nearchos; Davies, Justin E.; Malik, Iqbal S.; Aguado-Sierra, Jazmin; Willson, Keith; Foale, Rodney A.; Parker, Kim H.; Hughes, Alun D.; Francis, Darrel P.; Mayet, Jamil

2008-01-01

150

What are the long-term results of cardiac valve replacements in left sided endocarditis with a history of i.v. drug abuse?  

PubMed

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was what the long-term results of cardiac valve replacements are in left sided endocarditis with a history of i.v. drug abuse? A total of 286 publications were found using the reported search, of which nine presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patients group studied, study type, relevant outcomes, results, and study weaknesses of these papers were tabulated. We conclude that cardiac valve replacement for left sided endocarditis in i.v. drug users carries a substantial mortality. Continued drug abuse is the commonest cause of death in this patient group. In contrast, the type of valve used to perform the replacement does not seem to influence mortality. Postoperative management should focus on treatment of the drug addiction. PMID:17670659

Wahba, Alexander; Nordhaug, Dag

2006-06-01

151

Comparative effects of metoprolol and celiprolol on cardiac hemodynamics and left ventricular volume at rest and during exercise-induced angina.  

PubMed

Celiprolol is a cardioselective beta-adrenoceptor antagonist with attributed cardiostimulant properties. Its hemodynamic profile was compared in a dose-response study with that of metoprolol, which is also cardioselective but lacks cardiostimulatory activity. In 24 patients with angiographically proved coronary artery disease, simultaneous hemodynamic and left ventricular ejection fraction (EF) values were determined at rest in the control (drug-free) state and repeated 3 to 5 minutes after each of four intravenous boluses of celiprolol, 1, 1, 2, and 4 mg, or equivalent beta-blocking doses of metoprolol, 1.25, 1.25, 2.5, and 5.0 mg. The effects of each drug on hemodynamics during exercise-induced angina were determined by exercise testing in the control state and after the maximum cumulative dose of each drug. At rest, metoprolol reduced heart rate, cardiac index, and the left ventricular EF and increased pulmonary artery occluded pressure (PAOP), systemic vascular resistance, and left ventricular end-systolic and end-diastolic volumes. Celiprolol increased cardiac and stroke volume indices and the EF; the PAOP was reduced without change in other measured variables. During exercise, metoprolol significantly increased the PAOP, which was unchanged by celiprolol. At exercise both drugs reduced cardiac index and heart rate, but neither altered the EF. The cardiac function curve demonstrated greater depression at rest after metoprolol than after celiprolol; these differences were attenuated during dynamic exercise. The lesser adverse impact of celiprolol on cardiac function may be attributable to ancillary cardiac stimulatory properties offsetting the cardiac depression after beta-adrenoceptor blockade. PMID:2935349

Silke, B; Verma, S P; Frais, M A; Reynolds, G; Taylor, S H

1986-01-01

152

Cardiac hemangioma located at the apex of the left ventricle: a rare case report.  

PubMed

We report the case of a 67-year-old man who was found to have asymptomatic murmurs during his health check-up. Echocardiography revealed a mobile spherical mass in the left ventricle (LV), whereas magnetic resonance imaging (MRI) study revealed a well-circumscribed heterogeneous mass in the LV with its base attached to the LV apex. To the best of our knowledge, such a case of hemangioma, particularly its rare location at the apex of the LV, and its asymptomatic conduction disturbance has not yet been reported in the medical literature. Because of successful surgical intervention, the patient is in good health without any further tumor recurrence at 24 months after the diagnosis. PMID:23397831

Lin, C T; Lee, C Y; Hong, G J; Tsai, Y T; Lin, C Y; Ke, H Y; Tsai, C S

153

Prediction of acute cardiac rejection by changes in left ventricular volumes  

SciTech Connect

Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection.

Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

1988-11-01

154

Creatine Kinase and Lactate Dehydrogenase in the Muscles Encountered during Median Sternotomy and the Myocardium of the Cardiac Chambers.  

National Technical Information Service (NTIS)

The validity of using kinase MB and lactate dehydrogenase, serum isoenzymes to confirm the diagnosis of perioperative m ycocardial infarction in patients who have had cardiac operations has been questioned, since both have been detected in sketetal muscle...

G. M. Graeber

1985-01-01

155

Four-chamber heart modeling and automatic segmentation for 3-D cardiac CT volumes using marginal space learning and steerable features.  

PubMed

We propose an automatic four-chamber heart segmentation system for the quantitative functional analysis of the heart from cardiac computed tomography (CT) volumes. Two topics are discussed: heart modeling and automatic model fitting to an unseen volume. Heart modeling is a nontrivial task since the heart is a complex nonrigid organ. The model must be anatomically accurate, allow manual editing, and provide sufficient information to guide automatic detection and segmentation. Unlike previous work, we explicitly represent important landmarks (such as the valves and the ventricular septum cusps) among the control points of the model. The control points can be detected reliably to guide the automatic model fitting process. Using this model, we develop an efficient and robust approach for automatic heart chamber segmentation in 3-D CT volumes. We formulate the segmentation as a two-step learning problem: anatomical structure localization and boundary delineation. In both steps, we exploit the recent advances in learning discriminative models. A novel algorithm, marginal space learning (MSL), is introduced to solve the 9-D similarity transformation search problem for localizing the heart chambers. After determining the pose of the heart chambers, we estimate the 3-D shape through learning-based boundary delineation. The proposed method has been extensively tested on the largest dataset (with 323 volumes from 137 patients) ever reported in the literature. To the best of our knowledge, our system is the fastest with a speed of 4.0 s per volume (on a dual-core 3.2-GHz processor) for the automatic segmentation of all four chambers. PMID:18955181

Zheng, Yefeng; Barbu, Adrian; Georgescu, Bogdan; Scheuering, Michael; Comaniciu, Dorin

2008-11-01

156

Left Atrial Myxoma Presenting with Unusual Cystic Form  

PubMed Central

Cardiac myxomas are the most common primary benign tumors of uncertain etiology. They usually present as polypoid or oval-shaped masses projecting into a heart chamber from the interatrial septum and have a soft, gelatinous consistency without a cystic structure. We report a case of left atrial myxoma with a single cystic form.

Park, Kwon Jae; Park, Jong Yoon

2013-01-01

157

Radiation dose exposure of patients undergoing 320-row cardiac CT for assessing coronary angiography and global left ventricular function.  

PubMed

A 320-row multidetector CT provides the capability for prospective electrocardiogram (ECG)-gated coronary CT angiography (CTA) and tube current modulated cardiac function assessment (CFA). We assessed and compared the effective radiation dose of these two modes. On a prospective basis, we performed ECG-gated cardiac CT on 119 patients (87 were males). For heart rates (HRs) /=80 bpm were scanned with either two or three heartbeats acquisitions, respectively. We used two types of scans. One type was based on a prospective ECG-gated CTA mode and the other using a tube current modulated CFA mode covering an entire R-R interval. The mean BMI of patients was 25.4 (range 18.8-49.3). Fifty-one patients (42.9 %) underwent CFA scanning, while the remaining 68 (57.1 %) had CTA. The majority of patients completed the scan in a single heartbeat (59.7 %). The mean dose of CTA mode at 65-85 % phase window for one and two heartbeats was 3.68 mSv (2.40-7.23) and 8.61 mSv (6.76-10.60), respectively. The mean dose of CFA mode for a single heartbeat measurement with dose modulation (25 % dose for CFA, and 100 % dose during 65-85 % phase window for CTA) was 6.32 mSv (4.69-8.89). CTA with prospective ECG-gating allows for acceptable image quality and radiation dose. HR reduction is mandatory to minimize radiation exposure. Global left ventricle function can be assessed with a single heartbeat within an acceptable radiation dose. PMID:22610716

Chen, Chien-Ming; Liu, Yuan-Chang; Chen, Chun-Chi; Wen, Ming-Shien; Hung, Chien-Fu; Wan, Yung-Liang

2012-05-18

158

Vulnerable Myocardial Interstitium in Patients With Isolated Left Ventricular Hypertrophy and Sudden Cardiac Death: A Postmortem Histological Evaluation  

PubMed Central

Background Concentric left ventricular hypertrophy (LVH) is independently associated with increased risk of sudden cardiac death (SCD). Some animal models of LVH display specific alterations of the myocardial interstitium that could increase myocardial vulnerability to ventricular arrhythmias, but these merit evaluation in humans with LVH and SCD. Methods and Results Twelve consecutive patients with isolated LVH and SCD (LVH+SCD) in the absence of hypertrophic cardiomyopathy, coronary disease, or other cardiac structural abnormality were ascertained in the Oregon Sudden Unexpected Death Study. Detailed postmortem comparisons were conducted with 18 controls who had isolated LVH and unnatural deaths (Control Group A) and 6 controls who had structurally normal hearts and unnatural deaths (Control Group B). Postmortem left ventricular myocardial sections were obtained for measurement of collagen volume fraction, characterization of gap junctions, and quantification of collagen subtypes. Heart weight normalized to body weight was higher in LVH+SCD cases (6.9±1.2 g/kg) than in Control Group A (5.3±1.4 g/kg) and Control Group B (4.2±0.3 g/kg); P=0.001. Collagen volume fraction was also higher in LVH+SCD cases (3.1±0.4) than in Control Group A (2.3±0.4) and Control Group B (1.6±0.3); P=0.0002. The relative amount of collagen III was significantly higher in LVH+SCD cases (33.0±4.4%) than in Control Group A (20.9±4.3%) and Control Group B (13.4±3.5%); P=0.0001. There was an overall increase in the number of connexin 43–labeled gap junctions with increasing myocyte size. No subject was found to have high-risk hypertrophic cardiomyopathy mutations. Conclusions In addition to the expected increase in myocardial mass and overall collagen content, SCD with isolated LVH was associated with relative abundance of type III collagen, a novel finding that warrants further mechanistic evaluation. (J Am Heart Assoc. 2012;1:e001511 doi: 10.1161/JAHA.111.001511.)

Tamarappoo, Balaji K.; John, Benjamin T.; Reinier, Kyndaron; Teodorescu, Carmen; Uy-Evanado, Audrey; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S.

2012-01-01

159

Beneficial effect of pericardial meshing on left ventricular pump performance in dogs.  

PubMed

To evaluate the effects of pericardial meshing (multiple incisions on the pericardium) on cardiac function, we examined left ventricular pump performance before and after pericardial meshing in six open chest dogs. We evaluated left ventricular systolic properties with the slope of end-systolic pressure-volume relation and diastolic properties with end-diastolic pressure-volume relation (chamber compliance). Overall left ventricular performance was assessed with end-diastolic pressure versus cardiac output relation. Left ventricular chamber compliance was increased (31.3%) with pericardial meshing compared with direct closure of the pericardium, and cardiac output was increased (26.7%) for any given left ventricular end-diastolic pressure. The slope of the end-systolic pressure-volume relation was not altered in pericardial meshing. These results suggest that pericardial meshing improves left ventricular pump performance as a result of increasing left ventricular chamber compliance. This technique may benefit cardiac pump performance that is depressed by the direct closure of the pericardium after cardiac operations. PMID:1992236

Oe, M; Asou, T; Morita, S; Fukamachi, K; Mitani, A; Tokunaga, K

1991-02-01

160

Quantification of the temporal component of left ventricular asynergy by gated cardiac blood pool scans  

SciTech Connect

Fourier analysis (F) has demonstrated that left ventricular (LV) dysfunction can be analyzed in two separate component: an amplitude (AM) and a temporal (T) component. Although the former dominates in hypokinesis and akinesis, and the latter in dyskinesis, they are almost always associated and combine to determine the clinical form of asynergy (AS). The mechanical consequences of the T component cannot be assessed continuously by F which requires setting of a threshold. In this study, the authors have analyzed the potential of a new index; the stroke volume efficiency (SV Eff) to evaluate the importance of T AS in patients (pts) with coronary artery disease studied by gated blood pool scans. The authors have studied 14 controls, 8 pts with coronary artery disease without infarction, 56 pts with myocardial infarction (MI) and 21 pts with LV aneurysm. The SV Eff was calculated as follows after normalization and smoothing of the series: maximum and minimum images were created first and a LV region of interest was traced using the F AM image. The SV Eff ratio was calculated within the LV region of interest as ''diastolic counts - systolic counts/maximum counts - minimum counts''. The SV Eff in controls was 94% +- 2. The authors conclude that SV Eff provides a quantitative measurement of T component of LV dysfunction and an estimate of the dyskinetic component in pts with LV aneurysm. It should prove useful to study these patients serially.

Solot, G.; Chevigne, M.; Rigo, P.

1985-05-01

161

Accurate segmentation framework for the left ventricle wall from cardiac cine MRI  

NASA Astrophysics Data System (ADS)

We propose a novel, fast, robust, bi-directional coupled parametric deformable model to segment the left ventricle (LV) wall borders using first- and second-order visual appearance features. These features are embedded in a new stochastic external force that preserves the topology of LV wall to track the evolution of the parametric deformable models control points. To accurately estimate the marginal density of each deformable model control point, the empirical marginal grey level distributions (first-order appearance) inside and outside the boundary of the deformable model are modeled with adaptive linear combinations of discrete Gaussians (LCDG). The second order visual appearance of the LV wall is accurately modeled with a new rotationally invariant second-order Markov-Gibbs random field (MGRF). We tested the proposed segmentation approach on 15 data sets in 6 infarction patients using the Dice similarity coefficient (DSC) and the average distance (AD) between the ground truth and automated segmentation contours. Our approach achieves a mean DSC value of 0.926+/-0.022 and AD value of 2.16+/-0.60 compared to two other level set methods that achieve 0.904+/-0.033 and 0.885+/-0.02 for DSC; and 2.86+/-1.35 and 5.72+/-4.70 for AD, respectively.

Sliman, H.; Khalifa, F.; Elnakib, A.; Soliman, A.; Beache, G. M.; Gimel'farb, G.; Emam, A.; Elmaghraby, A.; El-Baz, A.

2013-10-01

162

Recirculation subtraction for analysis of left-to-right-cardiac shunts: concise communication  

SciTech Connect

The object of this study is to improve the techniques for describing the lung dilution curve for shunt quantification by separating the effects of systemic recirculation on the curve from those of direct shunt return. The time of the systemic recirculation peak was estimated by determination of transit times from the right and left ventricles and lung. A gamma variate fit based on the distribution of points at that segment was applied to the recirculation curve and subtracted from the original lung dilution curve. Similar gamma variate fitting was performed for both primary and shunt curves. Rather than fitting the gamma variate of the shunt curve by the leading edge only, a larger portion could now be used since the trailing edge of the curve is clearer following recirculation subtraction. The algorithm is completely automatic, requiring no operator intervention or selection of curve-fitting regions. The correlation coefficient for comparison of the dilution-curve analysis with oximetry determinations was 0.92 in a series of 29 patients.

Houser, T.S.; MacIntyre, W.J.; Cook, S.A.; Go, R.T.; Moodie, D.S.; Ceimo, J.; Gallagher, J.H.

1981-12-01

163

QRS pattern and improvement in right and left ventricular function after cardiac resynchronization therapy: a radionuclide study  

PubMed Central

Background Predicting response to cardiac resynchronization therapy (CRT) remains a challenge. We evaluated the role of baseline QRS pattern to predict response in terms of improvement in biventricular ejection fraction (EF). Methods Consecutive patients (pts) undergoing CRT implantation underwent radionuclide angiography at baseline and at mid-term follow-up. The relationship between baseline QRS pattern and mechanical dyssynchrony using phase analysis was evaluated. Changes in left and right ventricular EF (LVEF and RVEF) were analyzed with regard to baseline QRS pattern. Results We enrolled 56 pts, 32 with left bundle branch block (LBBB), 4 with right bundle branch block (RBBB) and 20 with non-specific intraventricular conduction disturbance (IVCD). A total of 48 pts completed follow-up. LBBB pts had significantly greater improvement in LVEF compared to RBBB or non-specific IVCD pts (+9.6 ± 10.9% vs. +2.6 ± 7.6%, p = 0.003). Response (defined as ? 5% increase in LVEF) was observed in 68% of LBBB vs. 24% of non-specific IVCD pts (p = 0.006). None of the RBBB pts were responders. RVEF was significantly improved in LBBB (+5.0 ± 9.0%, p = 0.007), but not in non-specific IVCD and RBBB pts (+0.4 ± 5.8%, p = 0.76). At multivariate analysis, LBBB was the only predictor of LVEF response (OR, 7.45; 95% CI 1.80-30.94; p = 0.006), but not QRS duration or extent of mechanical dyssynchrony. Conclusions Presence of a LBBB is a marker of a positive response to CRT in terms of biventricular improvement. Pts with non-LBBB pattern show significantly less benefit from CRT than those with LBBB.

2012-01-01

164

[Cardiac arrhythmias in hypertensive subjects with and without left ventricular hypertrophy compared to the circadian profile of the blood pressure].  

PubMed

To evaluate possible correlations between cardiac arrhythmias and circadian pattern of blood pressure (BP) and of heart rate (HR), we studied 2 groups of 20 males with stable arterial hypertension of mild to moderate entity, with (Group I) or without (Group II) left ventricular hypertrophy (LVH). In patients with LVH the mean age (56 vs 46 years), the duration of the hypertensive state (48.1 vs 15.7 months), the thickening of interventricular septum (IVS; 13.7 vs 9.6 mm) and of the posterior wall of the left ventricle (13.2 vs 9.2 mm) and the mass of LV (149.8 vs 99.7 g/m2) were significantly greater (p less than 0.01). On the contrary, the 2 groups did not show significant differences concerning casual BP determined in the morning (178.3/108.4 vs 171.5/106.2 mmHg). After a pharmacological washout of 2 weeks, patients underwent a noninvasive, intermittent, monitoring of BP (every 15 min during daytime and every 30 min from 11 pm to 7 am), using a pressure meter II Del Mar Avionics, and a continuous monitoring of ECG for 24 hours, employing an instrument 445/B Del Mar Avionics. Mean 24-hour BP was not different in the 2 groups of patients (161.7/99.0 vs 158.2/98.3 mmHg); however, patients with LVH showed a significantly greater variability of BP in the morning (7 am-3 pm), while mean 24-hour HR was significantly less (71.6 vs 78.2 b/min).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2150345

Novo, S; Barbagallo, M; Abrignani, M G; Alaimo, G; Longo, B; Corrao, S; Nardi, E; Liquori, M; Forte, G; Raineri, A

1990-08-01

165

Multiaxial tomography of heart chambers by gated blood-pool emission computed tomography using a rotating gamma camera  

SciTech Connect

Fifteen patients and three volunteers underwent radionuclide blood-pool cardiac studies with electrocardiographic gating. Following conventional planar-gated imaging (anterior and left anterior oblique projections), emission computed tomography (ECT), using a rotating gamma camera, was performed.A series of transaxial tomograms of the cardiac chambers was obtained. The left ventricular short-axis plane, long-axis plane, and four-chamber-view plane were then reorganized; each chamber was visualized separately. Compared to gated planar imaging, this technique showed regional asynergy more clearly in patients with myocardial infarction and demonstrated dilatation of the atria and ventricles more accurately in patients with an atrial septal defect and valvular heart diseases. In addition, when a section of the heart is otained at any angle with gated blood pool ECT, three-dimensional assessment of cardiac chambers in motion is more precise; mutual superimposition becomes unnecessary.

Tamaki, N.; Mukai, T.; Ishii, Y.; Yonekura, Y.; Yamamoto, K.; Kadota, K.; Kambara, H.; Kawai, C.; Torizuka, K.

1983-05-01

166

[The first experience with X-ray endovascular closure of the left atrial auricle using an Amplatzer Cardiac Plug in patients with atrial fibrillation].  

PubMed

Atrial fibrillation is the most common cardiac arrhythmia in clinical practice. Long-term anticoagulant therapy is used to prevent thrombosis in the left atrial (LA) auricle and, as a consequence, thrombolisms. However, some patients have contraindications to its use. The paper considers different alternative methods for preventing thromboembolic events and particularly one of the most common presently encountered ones - percutaneous transcatheter LA auricle excision, by applying the Amplatzer Cardiac Plug. There are also data on the authors' experience in using this device. PMID:23700919

Samko, A N; Merkulov, E V; Pevzner, D V; Guchaev, R V; Mironov, V M

167

Comparison of cardiac output of the left and right side of the heart by ultrafast computed tomography  

SciTech Connect

Ultrafast computed tomography (CT) evaluation of cardiac output (CO) can be determined using indicator dilution theory. The concentration of an iodinated contrast agent injected into a vein of a subject can be measured as a function of time by serial EKG, gated CT imaging. The contrast density of the blood pool measured by CT defines the indicator concentration. CT CO is proportional to the area under a time density curve from a region of the blood pool. Proper subject position and scanning timing allows CT to measure CO in the pulmonary (PA) artery and the aorta (AO) with the same contrast bolus. Three anesthetized dogs were multiply scanned following simultaneous injections of contrast and radioactive tracer microspheres. Microsphere CO was determined by reference withdrawal method. Multiple thermodilution CO measurements were made just prior and after each CT CO procedure. 24 comparisons were made of thermodilution, microsphere and CT CO measured in the PA (right sided CO (RSCO)) and the AO (left sided CO (LSCO)). CT CO was calculated as the ratio of the volume of contrast injected to the time density curve area corrected for the relation of contrast density to CT number. RSCO agreed very closely to LSCO (r = .99, p < .001; y = 1.0x +/- .32). RSCO correlated to thermodilution (r = .96, p < .001; y = 1.2x +/- 1.3) and microsphere CO (r = .93, p < .001; y = .69x +/- 1.3). These data show that CT CO measurements can be made in the PA and AO with equal accuracy.

Wolfkiel, C.J.; Ferguson, J.L.; Law, W.R.; Chomka, E.V.; Brundage, B.H.

1986-03-05

168

Complex cardiac congenital defects in an adult dog: an ultrasonographic and magnetic resonance imaging study.  

PubMed

This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of the ASD was measured by magnetic resonance imaging (MRI). PMID:19949552

García-Rodríguez, M Belén; Granja, M Angeles Ríos; García, C César Pérez; Gonzalo Orden, Jose M; Cano Rábano, Maria J; Prieto, Inmaculada Diez

2009-09-01

169

Complex cardiac congenital defects in an adult dog: An ultrasonographic and magnetic resonance imaging study  

PubMed Central

This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of the ASD was measured by magnetic resonance imaging (MRI).

Garcia-Rodriguez, M. Belen; Granja, M. Angeles Rios; Garcia, C. Cesar Perez; Gonzalo Orden, Jose M.; Cano Rabano, Maria J.; Prieto, Inmaculada Diez

2009-01-01

170

Left ventricular hypertrabeculation/noncompaction as a cardiac manifestation of Duchenne muscular dystrophy under non-invasive positive-pressure ventilation.  

PubMed

Though cardiac involvement is a frequent finding in patients with Duchenne muscular dystrophy (DMD) at the wheel-chair-bound stage, left ventricular hypertrabeculation (LVHT) has not been reported. The patient is a 28-year-old male with the typical clinical features of end stage DMD. Since the age of 16 years he required ventilatory support by means of non-invasive positive-pressure ventilation (NIPPV), initially intermittently and since age 27 permanently. Since the age of 21 years he developed chronic heart failure, and since age 24 atrial flutter, successfully treated with amiodarone. After discontinuation of amiodarone because of hyperthyroidism, he developed atrial fibrillation. Echocardiography at age 28 revealed mitral insufficiency, enlarged left atrial diameter, and, surprisingly, LVHT. Since LVHT was absent at the initial echocardiographic examination, it was regarded acquired. The case shows that cardiac involvement in DMD may not only comprise rhythm abnormalities, valve abnormalities, and dilative cardiomyopathy, but also LVHT in single cases. PMID:16128380

Finsterer, Josef; Gelpi, Ellen; Stöllberger, Claudia

2005-08-01

171

Left ventricular noncompaction cardiomyopathy in Barth syndrome: an example of an undulating cardiac phenotype necessitating mechanical circulatory support as a bridge to transplantation.  

PubMed

Barth syndrome (BTHS) is associated with myocardial disease, frequently left ventricular noncompaction cardiomyopathy, which may necessitate cardiac transplantation or lead to death in some patients. We report a child with BTHS who had an "undulating cardiac phenotype" and ultimately developed decompensated heart failure requiring mechanical circulatory support with a ventricular assist device as a bridge to transplantation. His course was complicated by acute lung injury requiring placement of an in-line oxygenator to maintain end-organ function. Not only was his course complicated by cardiac and respiratory failure but his BTHS associated comorbidities complicated the management of his therapy using mechanical assist device support. He was successfully supported and subsequently was transplanted. Here we discuss the management of a child with BTHS using mechanical circulatory support and describe the use of an in-line oxygenator, Quadrox, with the Berlin Excor device. PMID:22427193

Hanke, Samuel P; Gardner, Aimee B; Lombardi, John P; Manning, Peter B; Nelson, David P; Towbin, Jeffrey A; Jefferies, John L; Lorts, Angela

2012-03-17

172

Cardiac Output Measurement in Ventilated Lambs with a Significant Left-to-Right Shunt Using the Modified Carbon Dioxide Fick Method  

Microsoft Academic Search

Background: It remains a great challenge to measure systemic blood flow in critically ill newborns. In a former study we validated the modified carbon dioxide Fick (mCO2F) method for measurement of cardiac output in a newborn lamb model. In this new study we studied the influence of a left-to-right shunt on the accuracy of the mCO2F method. Objective: To analyze

Willem P. de Boode; Jeroen C. W. Hopman; Marc H. W. A. Wijnen; Ronald B. Tanke; Hans G. van der Hoeven; K. Djien Liem

2010-01-01

173

Intravenous Immunoglobulin Reduces Anti-HLA Alloreactivity and Shortens Waiting Time to Cardiac Transplantation in Highly Sensitized Left Ventricular Assist Device Recipients  

Microsoft Academic Search

Background—Recipients of left ventricular assist devices (LVADs) develop prominent B-cell hyperreactivity. We investigated the influence of anti-HLA antibodies on waiting time to cardiac transplantation in LVAD recipients and compared the effects of 2 immunomodulatory regimens on anti-HLA serum reactivity. Methods and Results—Fifty-five previously nonsensitized LVAD recipients of a TCI device implanted between 1990 and 1996 were studied. Patients with anti-HLA

Ranjit John; Katherine Lietz; Elizabeth Burke; Jan Ankersmit; Donna Mancini; Nicole Suciu-Foca; Niloo Edwards; Eric Rose; Mehmet Oz; Silviu Itescu

174

Molecular Basis and Genetic Aspects of the Development of the Cardiac Chambers and Conduction System: Relevance to Heart Rhythm  

Microsoft Academic Search

\\u000a This chapter discusses how transcription factors regulate the differentiation of embryonic myocardium into working, and conduction\\u000a system myocardium. The components of the cardiac conduction system originate from embryonic myocardium that has maintained\\u000a important features of its primitive phenotype. The development of the conduction system and the origin and characteristics\\u000a of pacemaker cells will be discussed in detail. We explain how

Martijn L. Bakker; Vincent M. Christoffels; Antoon F. M. Moorman

175

Hydrogen sulfide suppresses the expression of MMP-8, MMP-13, and TIMP-1 in left ventricles of rats with cardiac volume overload.  

PubMed

Aim:To study the effects of hydrogen sulfide (H2S) on the left ventricular expression of MMP-8, MMP-13, and TIMP-1 in a rat model of congenital heart disease.Methods:Male SD rats underwent abdominal aorta-inferior vena cava shunt operation. H2S donor NaHS (56 ?mol·kg(-1)·d(-1), ip) was injected from the next day for 8 weeks. At 8 weeks, the hemodynamic parameters, including the left ventricular systolic pressure (LVSP), the left ventricular peak rate of contraction and relaxation (LV±dp/dtmax) and the left ventricular end diastolic pressure (LVEDP) were measured. The left ventricular tissues were dissected out, and hydroxyproline and collagen I contents were detected with ELISA. The expression of MMP-8, MMP-13, and a tissue inhibitor of metalloproteinase-1 (TIMP-1) in the tissues was measured using real-time PCR, Western blotting, and immunohistochemistry, respectively.Results:The shunt operation markedly reduced LVSP and LV±dp/dtmax, increased LVEDP, hydroxyproline and collagen I contents, as well as the mRNA and protein levels of MMP-8, MMP-13, and TIMP-1 in the left ventricles. Chronic treatment of the shunt operation rats with NaHS effectively prevented the abnormalities in the hemodynamic parameters, hydroxyproline and collagen I contents, and the mRNA and protein levels of MMP-13 and TIMP-1 in the left ventricles. NaHS also prevented the increase of MMP-8 protein expression, but did not affect the increase of mRNA level of MMP-8 in the shunt operation rats.Conclusion:H2S suppresses protein and mRNA expression of MMP-8, MMP-13, and TIMP-1 in rats with cardiac volume overload, which may be contributed to the amelioration of ventricular structural remodeling and cardiac function. PMID:23974514

Zhang, Chao-Ying; Li, Xiao-Hui; Zhang, Ting; Fu, Jin; Cui, Xiao-Dai

2013-08-26

176

Relation of the ischaemic substrate to left ventricular remodelling by cardiac magnetic resonance at 1.5 T in rabbits  

PubMed Central

Objectives Contrast-enhanced cardiac magnetic resonance (CMR) for infarct sizing has been validated in large animals, but studies and follow-up are restricted. We sought to 1) validate CMR for assessment of myocardial area at risk (MAR) and infarct size (IS) in a rabbit model of reperfused myocardial infarction (MI); 2) analyse the relation between ischaemic substrates and subsequent left ventricular (LV) remodelling. Methods Experimental reperfused acute MI was induced in 16 rabbits. Ten animals underwent cross-registered cine and contrast-enhanced CMR and histopathology at day 3 for assessment of MAR and IS (group#1). The remaining 6 rabbits had serial CMR for the study of LV remodelling (group#2). Results In group#1, mean IS was 12.7±6.4% and 12.7±6.9% of total LV myocardial mass on CMR (late-enhancement technique) and histopathology (P=0.52; r=0.93). No significant difference occurred between CMR and histopathology for the calculation of MAR and IS/MAR ratio (P=0.18 and P=0.17), whereas correlations were strong (r=0.92 and r=0.95). In group#2, mean LV end-diastolic, end-systolic volumes and LV mass were significantly increased at 3 weeks compared with measurements at day 3 (P<0.01). Significant correlations between initial IS and the increase in LV end-diastolic volume (r=0.66) and the increase in LV mass (r=0.48) were observed, as well as correlations between initial MAR and the increase in LV end-diastolic volume (r=0.70) and the increase in LV mass (r=0.37). Conclusions Comprehensive CMR provides accurate assessment of IS and MAR in reperfused rabbit MI. Infarct size is closely related to LV remodelling. Through the infarct size/MAR ratio, this approach has great potential for assessing interventions aimed at cardioprotection.

Mansencal, Nicolas; Tissier, Renaud; Deux, Jean-Francois; Ghaleh, Bijan; Couvreur, Nicolas; Rienzo, Mario; Gueret, Pascal; Rahmouni, Alain; Berdeaux, Alain; Garot, Jerome

2010-01-01

177

Exercise training does not improve cardiac function in compensated or decompensated left ventricular hypertrophy induced by aortic stenosis.  

PubMed

There is ample evidence that regular exercise exerts beneficial effects on left ventricular (LV) hypertrophy, remodeling and dysfunction produced by ischemic heart disease or systemic hypertension. In contrast, the effects of exercise on pathological LV hypertrophy and dysfunction produced by LV outflow obstruction have not been studied to date. Consequently, we evaluated the effects of 8 weeks of voluntary wheel running in mice (which mitigates post-infarct LV dysfunction) on LV hypertrophy and dysfunction produced by mild (mTAC) and severe (sTAC) transverse aortic constriction. mTAC produced ~40% LV hypertrophy and increased myocardial expression of hypertrophy marker genes but did not affect LV function, SERCA2a protein levels, apoptosis or capillary density. Exercise had no effect on global LV hypertrophy and function in mTAC but increased interstitial collagen, and ANP expression. sTAC produced ~80% LV hypertrophy and further increased ANP expression and interstitial fibrosis and, in contrast with mTAC, also produced LV dilation, systolic as well as diastolic dysfunction, pulmonary congestion, apoptosis and capillary rarefaction and decreased SERCA2a and ryanodine receptor (RyR) protein levels. LV diastolic dysfunction was likely aggravated by elevated passive isometric force and Ca(2+)-sensitivity of myofilaments. Exercise training failed to mitigate the sTAC-induced LV hypertrophy and capillary rarefaction or the decreases in SERCA2a and RyR. Exercise attenuated the sTAC-induced increase in passive isometric force but did not affect myofilament Ca(2+)-sensitivity and tended to aggravate interstitial fibrosis. In conclusion, exercise had no effect on LV function in compensated and decompensated cardiac hypertrophy produced by LV outflow obstruction, suggesting that the effect of exercise on pathologic LV hypertrophy and dysfunction depends critically on the underlying cause. PMID:21291889

van Deel, Elza D; de Boer, Martine; Kuster, Diederik W; Boontje, Nicky M; Holemans, Patricia; Sipido, Karin R; van der Velden, Jolanda; Duncker, Dirk J

2011-02-01

178

Sudden death as presenting symptom caused by cardiac primary multicentric left ventricle rhabdomyoma, in an 11-month-old baby. An immunohistochemical study  

PubMed Central

This case report describes a sudden cardiac death in an apparent healthy 11-month-old infant caused by a multifocal cardiac rhabdomyoma. Parents reported that a few days before the child had fallen to the ground getting a little superficial injury to the scalp. The authors hypothesize that it may have been a transient loss of consciousness episode caused by the cardiac tumour. After the gross examination, histological investigation supported by immunohistochemical analysis using antibody anti- Myoglobin, Actin, Vimentin, Desmin, CD34, S-100, Ki-67 was carried out for the diagnosis. Death was attributed to a multifocal cardiac rhabdomyoma, a benign tumour of striated muscle, which has been completely asymptomatic. In particular, one mass filled the entire posterior wall of the left ventricle. The insidious development of benign cardiac tumours also in infants and children is outlined, focusing on the responsible mechanisms of sudden death in such cases and providing a reference for additional study on these subjects. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7163626988365078

2012-01-01

179

Exercise effects on cardiac size and left ventricular diastolic function: relationships to changes in fitness, fatness, blood pressure and insulin resistance  

PubMed Central

Objectives To determine exercise training effects on cardiac size and left ventricular (LV) diastolic function and relationships of exercise induced changes in physiological and body composition parameters with cardiac parameters. Design Prospective, randomised controlled trial. Subjects Men and women (63.6 (5.7) years, body mass index 29.5 (4.4)?kg/m2) with untreated hypertension (systolic blood pressure (BP) 130–159 or diastolic BP 85–99?mm?Hg). Main outcome measures Cardiac size and LV diastolic function, peak oxygen uptake (Vo2), muscle strength, general and abdominal fatness, and insulin resistance. Interventions 6 months of exercise training versus usual care. Results When analysed by group at six months, cardiac size and LV diastolic function did not differ between exercisers (n??=??51) and controls (n??=??53), whereas exercisers had significantly higher peak Vo2 (28 v 24?ml/kg/min) and strength (383 v 329?kg), and lower fatness (34% v 37%), diastolic BP (73 v 75?mm?Hg) and insulin resistance (quantitative insulin sensitivity check index 0.35 v 0.34) versus controls (all p???0.05). By regression analysis, among six month changes, increased peak Vo2 and reduced abdominal fat were associated with increased cardiac size. Increased peak Vo2 and reduced abdominal fat, BP and insulin resistance were associated with improved LV diastolic function. r Values ranged from 0.20 to 0.32 (p???0.05). Conclusions When examined by group assignment, exercise had no effect on cardiac size or LV diastolic function. When individual variations in six month changes were examined, participants attaining the greatest increases in fitness and reductions in abdominal fatness, insulin resistance and BP showed a modest trend towards physiological hypertrophy characterised by increased cardiac size and improved LV diastolic function. These results suggest that decreased abdominal fatness may have a role in improving cardiovascular health.

Stewart, K J; Ouyang, P; Bacher, A C; Lima, S; Shapiro, E P

2006-01-01

180

Prediction of Cardiac Events in Patients with Reduced Left Ventricular Ejection Fraction Using Dobutamine Cardiovascular Magnetic Resonance Assessment of Wall Motion Score Index  

PubMed Central

Objectives To assess the utility of dobutamine cardiovascular magnetic resonance (DCMR) results for predicting cardiac events in individuals with reduced left ventricular ejection fraction (LVEF). Background It is unknown whether DCMR results identify a poor cardiac prognosis when the resting LVEF is moderately to severely reduced. Methods Two-hundred consecutive patients aged 30 to 88 (average 64) years with a LVEF ?55% that were poorly suited for stress echocardiography, underwent DCMR in which LV wall motion score index (WMSI), defined as the average wall motion of the number of segments scored, was assessed at rest, during low dose, and after peak intravenous infusion of dobutamine/atropine. All participants were followed for an average of 5 years after DCMR to ascertain the post testing occurrence of cardiac death, myocardial infarction (MI), and unstable angina or congestive heart failure warranting hospitalization. Results After accounting for risk factors associated with coronary arteriosclerosis and MI, a stress induced increase in WMSI during DCMR was associated with future cardiac events (p< 0.001). After accounting for resting LVEF, a DCMR stress induced change in WMSI added significantly to predicting future cardiac events (p=0.003), but this predictive value was confined primarily to those with a LVEF >40%. Conclusions In individuals with mild to moderate reductions in LVEF (40% to 55%), dobutamine induced increases in WMSI forecast MI and cardiac death to a greater extent than an assessment of resting LVEF. In those with a LVEF < 40%, a dobutamine induced increase in WMSI does not predict MI and cardiac death beyond the assessment of resting LVEF.

Dall'Armellina, Erica; Morgan, Timothy M.; Mandapaka, Sangeeta; Ntim, William; Carr, J. Jeffrey; Hamilton, Craig A.; Hoyle, John; Clark, Hollins; Clark, Paige; Link, Kerry M.; Case, Doug; Hundley, W. Gregory

2013-01-01

181

Left Ventricular or Biventricular Pacing Improves Cardiac Function at Diminished Energy Cost in Patients With Dilated Cardiomyopathy and Left Bundle-Branch Block  

Microsoft Academic Search

Background—Left ventricular or biventricular pacing\\/stimulation can acutely improve systolic function in patients with dilated cardiomyopathy (DCM) and intraventricular conduction delay by resynchronizing contraction. Most heart failure therapies directly enhancing systolic function do so while concomitantly increasing myocardial oxygen consumption (MVO2). We hypothesized that pacing\\/stimulation, in contrast, incurs systolic benefits without raising energy demand. Methods and Results—Ten DCM patients with left

Gregory S. Nelson; Ronald D. Berger; Barry J. Fetics; Maurice Talbot; Julio C. Spinelli; Joshua M. Hare; David A. Kass

182

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

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

Schunkert, H; Dzau, V J; Tang, S S; Hirsch, A T; Apstein, C S; Lorell, B H

1990-01-01

183

Genome-wide expression profiling of a cardiac pressure overload model identifies major metabolic and signaling pathway responses  

Microsoft Academic Search

Cardiac hypertrophy is a predictor of cardiovascular morbidity and mortality independent of other risk factors. Pressure overload induces the development of left ventricular hypertrophy (LVH) and left atrial enlargement (LAE) in the mammalian heart. To systematically investigate the transcriptional changes, which mediate these processes, we have performed a genome-wide transcriptional profiling of each of the four heart chambers from mice

Roger A. Wagner; Raymond Tabibiazar; Jennifer Powers; Daniel Bernstein; Thomas Quertermous

2004-01-01

184

A multi-physics and multi-scale lumped parameter model of cardiac contraction of the left ventricle: a conceptual model from the protein to the organ scale.  

PubMed

In cardiovascular computational physiology the importance of understanding cardiac contraction as a multi-scale process is of paramount importance to understand causality across different scales. Within this study, a multi-scale and multi-physics model of the left ventricle that connects the process of cardiac excitation and contraction from the protein to the organ level is presented in a novel way. The model presented here includes the functional description of a cardiomyocyte (cellular scale), which explains the dynamic behaviour of the calcium concentration within the cell whilst an action potential develops. The cell domain is coupled to a domain that determines the kinetics of the sliding filament mechanism (protein level), which is at the basis of cardiac contraction. These processes are then linked to the generation of muscular force and from there to the generation of pressure inside the ventricle. This multi-scale model presents a coherent and unified way to describe cardiac contraction from the protein to the organ level. PMID:22921613

Bhattacharya-Ghosh, Benjamin; Schievano, Silvia; Díaz-Zuccarini, Vanessa

2012-08-24

185

Prone breast forward intensity-modulated radiotherapy for Asian women with early left breast cancer: factors for cardiac sparing and clinical outcomes  

PubMed Central

Since December 2009, after breast-conserving surgery for Stage 0–I cancer of the left breast, 21 women with relatively pendulous breasts underwent computed tomography prone and supine simulations. The adjuvant radiotherapy was 50 Gy in 25 fractions to the left breast alone. Four plans—conventional wedged tangents and forward intensity-modulated radiotherapy (fIMRT) in supine and prone positions—were generated. fIMRT generated better homogeneity in both positions. Prone position centralized the breast tissue by gravity and also shortened the breast width which led to better conformity in both planning techniques. Prone fIMRT significantly reduced doses to left lung, Level I and Level II axilla. The mean cardiac doses did not differ between positions. Among the four plans, prone fIMRT produced the best target dosimetry and normal organ sparing. In subgroup analysis, patients with absolute breast depth > 7 cm in the prone position or breast depth difference > 3 cm between positions had significant cardiac sparing with prone fIMRT. Sixteen patients with significant cardiac sparing in prone position were treated using prone fIMRT and the others using supine fIMRT. All patients received a supine electron tumor bed boost of 10 Gy in 5 fractions. No patients developed Grade 2 or worse acute or late toxicities. There was no difference in the number of segments or beams, monitor units, treatment time, or positioning reproducibility between prone and supine positions. At a median follow-up time of 26.8 months, no locoregional or distant recurrence or death was noted.

Chen, Jenny Ling-Yu; Cheng, Jason Chia-Hsien; Kuo, Sung-Hsin; Chan, Hsing-Min; Huang, Yu-Sen; Chen, Yu-Hsuan

2013-01-01

186

Tako-tsubo-like left ventricular dysfunction with ST-segment elevation: A novel cardiac syndrome mimicking acute myocardial infarction  

Microsoft Academic Search

Background Peculiar asynergy, which consists of hypokinesis or akinesis from the mid portion to the apical area and hyperkinesis of the basal area on contrast left ventriculogram, is rare. Because the end-systolic left ventriculogram looks like a “tako-tsubo,” which was used for trapping octopuses in Japan, we proposed the term “tako-tsubo-like left ventricular dysfunction.” Our aim was to evaluate its

Satoshi Kurisu; Hikaru Sato; Takuji Kawagoe; Masaharu Ishihara; Yuji Shimatani; Kenji Nishioka; Yasuyuki Kono; Takashi Umemura; Suji Nakamura

2002-01-01

187

A Comprehensive Analysis of Cardiac Dose in Balloon-Based High-Dose-Rate Brachytherapy for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To investigate radiation dose to the heart in 60 patients with left-sided breast cancer who were treated with balloon-based high-dose-rate brachytherapy using MammoSite or Contura applicators. Methods and Materials: We studied 60 consecutive women with breast cancer who were treated with 34 Gy in 10 twice-daily fractions using MammoSite (n = 37) or Contura (n = 23) applicators. The whole heart and the left and right ventricles were retrospectively delineated, and dose-volume histograms were analyzed. Multiple dosimetrics were reported, such as mean dose (D{sub mean}); relative volume receiving 1.7, 5, 10, and 20 Gy (V1.7, V5, V10, and V20, respectively); dose to 1 cc (D{sub 1cc}); and maximum point dose (D{sub max}). Biologic metrics, biologically effective dose and generalized equivalent uniform dose were computed. The impact of lumpectomy cavity location on cardiac dose was investigated. Results: The average {+-} standard deviation of D{sub mean} was 2.45 {+-} 0.94 Gy (range, 0.56-4.68) and 3.29 {+-} 1.28 Gy (range, 0.77-6.35) for the heart and the ventricles, respectively. The average whole heart V5 and V10 values were 10.2% and 1.3%, respectively, and the heart D{sub max} was >20 Gy in 7 of 60 (11.7%) patients and >25 Gy in 3 of 60 (5%) patients. No cardiac tissue received {>=}30 Gy. The V1.7, V5, V10, V20, and D{sub mean} values were all higher for the ventricles than for the whole heart. For balloons located in the upper inner quadrant of the breast, the average whole heart D{sub mean} was highest. The D{sub mean}, biologically effective dose, and generalized equivalent uniform dose values for heart and ventricles decreased with increasing minimal distance from the surface of the balloon. Conclusions: On the basis of these comprehensive cardiac dosimetric data, we recommend that cardiac dose be routinely reported and kept as low as possible in balloon-based high-dose-rate brachytherapy treatment planning for patients with left-sided breast cancer so the correlation with future cardiac toxicity data can be investigated.

Valakh, Vladimir, E-mail: vladimir@valakh.com [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Kim, Yongbok; Werts, E. Day; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Drexel University College of Medicine, Allegheny Campus, Pittsburgh, PA (United States)

2012-04-01

188

Treatment with a copper-selective chelator causes substantive improvement in cardiac function of diabetic rats with left-ventricular impairment  

PubMed Central

Background Defective copper regulation is implicated as a causative mechanism of organ damage in diabetes. Treatment with trientine, a divalent-copper-selective chelator, improves arterial and renal structure/function in diabetes, wherein it also ameliorates left-ventricular (LV) hypertrophy. However, direct in vivo evidence that trientine can improve cardiac function in heart failure has hitherto been lacking. Methods To determine whether trientine treatment could improve in vivo outcome, we measured cardiac function in groups of trientine-treated diabetic (TETA-DIA), non-drug-treated diabetic (DIA) and sham-treated control (SHAM) rats, by using in vivo high-field cardiac magnetic-resonance imaging (cMRI) and an ex vivo isolated-perfused working heart method. Forty age-matched animals underwent a cMRI scan after which 12 were randomized to the SHAM group and 28 underwent streptozotocin-injection; of these, 25 developed stable diabetes, and 12 were then randomized to receive no treatment for 16 weeks (DIA) and the other 13 to undergo 8-weeks’ untreated diabetes followed by 8-weeks’ drug treatment (TETA-DIA). Animals were studied again by cMRI at 8 and 16 weeks following disease induction, and finally by measurement of ex vivo cardiac function. Results After eight weeks diabetes, rats (DIA/TETA-DIA) had developed significant impairment of LV function, as judged by impairment of ejection fraction (LVEF), cardiac output (CO), and LV mass (LVM)/body-mass (all P?cardiac function by elevating LVEF and CO (both P?cardiac function in diabetic rats with substantive LV impairment. These results implicate impaired copper regulation in the pathogenesis of impaired cardiac function caused by diabetic cardiomyopathy, and support ongoing studies of trientine treatment in patients with heart failure.

2013-01-01

189

Evaluation of left ventricular wall motion and function in patients with previous myocardial infarction by three-dimensional 99m Tc-HSAD multigated cardiac pool imaging  

Microsoft Academic Search

To evaluate left ventricular (LV) wall motion stereoscopically from all directions and to calculate the LV volume by three-dimensional\\u000a (3D) imaging,99mTc-DTPA human serum albumin-multigated cardiac pool-single photon emission computed tomography (99mTc-MUGA-SPECT) was performed. A new data processing program was developed with the Application Visualization System-Medical\\u000a Viewer (AVS-MV) based on images obtained from99mTc-MUGA-SPECT. In patients with previous myocardial infarction, LV function

Junichi Yamazaki; Katsutoshi Naitou; Shuichi Ishida; Nariaki Uno; Kenichiro Saisho; Takehiko Munakata; Takeshi Morishita; Masaaki Takano; Yoshimasa Yabe

1997-01-01

190

Assessment of left ventricular function: comparison of cardiac multidetector-row computed tomography with two-dimension standard echocardiography for assessment of left ventricular function  

Microsoft Academic Search

Objective To compare global Left Ventricular (LV) systolic function assessment by 16-detector row Computed Tomography (MDCT) with Two-Dimensional Standard Echocardiography (2DSE) in a routine cardiology practice setting and to ascertain the degree of correlation between LV volumes and measurements obtained by 2DSE with those measured by MDCT. Methods In 52 patients with suspected coronary artery disease, a contrast enhanced MDCT

Darpan Bansal; Robin M. Singh; Mrinalini Sarkar; Ravi Sureddi; Kelly C. Mcbreen; Timothy Griffis; Anjan Sinha; Jawahar L. Mehta

2008-01-01

191

Left lower lobe atelectasis and consolidation following cardiac surgery: the effect of topical cooling on the phrenic nerve  

SciTech Connect

Retrospective and prospective analyses of chest radiographs of patients following coronary artery bypass surgery were undertaken. Left lower lobe pulmonary infiltrate and/or atelectasis developed in 13 of 40 (32.5%) patients who were operated upon without topical cooling of the heart with ice, and in 77 of 122 (63.1%) patients in one group and 34 of 40 (85.0%) patients in another group who were operated upon with topical cooling of the heart with ice. This difference was highly significant (p<0.001). Of the patients in one group in whom left lower lobe abnormality developed, 69.2% had paralysis or paresis of the left hemidiaphragm. It is evident that application of ice to the phrenic nerve can lead to temporary paralysis of the left leaf of the diaphragm, with subsequent development of left lower lobe pulmonary infiltrate and/or atelectasis.

Benjamin, J.J.; Cascade, P.N.; Rubenfire, M.; Wajszczuk, W.; Kerin, N.Z.

1982-01-01

192

Flow chamber  

SciTech Connect

A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

Morozov, Victor (Manassas, VA)

2011-01-18

193

[A cardiac embolic stroke due to malposition of the pacemaker lead in the left ventricle. A case report].  

PubMed

Misplacement of a permanent pacemaker lead has been described in several locations but rarely in the left ventricle. Less commonly, as described in our report, malposition may occur when the lead perforates the interatrial septum and extends across the left atrium and through the mitral valve into the left ventricle. The actual incidence of this pacemaker complication is unknown. Consequences may include perforation and systemic or cerebral thromboembolic events. We report the case of a patient with unintentionally misplaced left heart pacemaker lead admitted for neurological symptoms consistent with embolic stroke. The patient was on aspirin when symptoms occurred. The lead misplacement was not recognized at the time of implantation. Pacing threshold was normal. A 12-lead electrocardiogram showed right bundle branch block configuration paced complexes. By two-dimensional and transesophageal echocardiography, the pacemaker lead was carefully evaluated. The pacemaker lead crossed the interatrial septum, the left atrium, the mitral valve to be implanted in the left ventricular endocardium. To avoid the risk of future embolization, it was felt that the lead should be removed and right ventricular pacing established, once anticoagulation treatment was initiated. Successful percutaneous lead replacement was accomplished without sequelae. Measures to avoid lead misplacement are suggested. PMID:10832129

Agnelli, D; Ferrari, A; Saltafossi, D; Falcone, C

2000-01-01

194

Left Ventricular Pressure Measurement by Telemetry Is an Effective Means to Evaluate Transplanted Heart Function in Experimental Heterotopic Cardiac Xenotransplantation  

Microsoft Academic Search

Evaluation of the function of heterotopic cardiac transplants has traditionally been accomplished by either manual palpation or serial biopsies. Both methods have drawbacks. Palpation can be difficult to differentiate a pulse from the graft versus a transmitted pulse from the native aorta. Serial biopsies, though accurate, require multiple laparotomies, leading to increased morbidity and possibly mortality rates. In this study

K. A. Horvath; P. C. Corcoran; A. K. Singh; R. F. Hoyt; C. Carrier; M. L. Thomas III; M. M. Mohiuddin

2010-01-01

195

Tumorectomy with right thoracotomy for synchronous left atrial myxomas from Carney complex: report of a case.  

PubMed

This report describes a case of synchronous left atrial myxomas from Carney complex resected through a right thoracotomy. The patient was a 30-year-old female that had previously been diagnosed with Carney complex following a genetic examination. Preoperative echocardiography showed a left atrial tumor, but intraoperative inspection revealed another tumor in the left atrium. Carney complex was first described in the 1980s and cardiac myxoma from Carney complex can occur in any cardiac chamber, presenting multiple times with postoperative recurrences, occurring at any age and without any predilection for gender, and is inherited in an autosomal-dominant manner. Treatment for cardiac myxoma from Carney complex is very important for patient mortality and morbidity and, despite the endocrine nature of the disorder, cardiologists and cardiac surgeons play an important role. PMID:23052755

Ishida, Narihiro; Shimabukuro, Katsuya; Matsuno, Yukihiro; Arakawa, Yuki; Takemura, Hirofumi

2012-10-11

196

N-Terminal Pro-B-Type Natriuretic Peptide Plasma Levels as a Potential Biomarker for Cardiac Damage After Radiotherapy in Patients With Left-Sided Breast Cancer  

SciTech Connect

Purpose: Adjuvant radiotherapy (RT) after breast-conserving surgery has been associated with increased cardiovascular mortality. Cardiac biomarkers may aid in identifying patients with radiation-mediated cardiac dysfunction. We evaluated the correlation between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and troponin (TnI) and the dose of radiation to the heart in patients with left-sided breast cancer. Methods and Materials: NT-proBNP and TnI plasma concentrations were measured in 30 left-sided breast cancer patients (median age, 55.0 years) 5 to 22 months after RT (Group I) and in 30 left-sided breast cancer patients (median age, 57.0 years) before RT as control group (Group II). Dosimetric and geometric parameters of heart and left ventricle were determined in all patients of Group I. Seventeen patients underwent complete two-dimensional echocardiography. Results: NT-proBNP levels were significantly higher (p = 0.03) in Group I (median, 90.0 pg/ml; range, 16.7-333.1 pg/ml) than in Group II (median, 63.2 pg/ml; range, 11.0-172.5 pg/ml). TnI levels remained below the cutoff threshold of 0.07 ng/ml in both groups. In patients with NT-proBNP values above the upper limit of 125 pg/ml, there were significant correlations between plasma levels and V{sub 3Gy}(%) (p = 0.001), the ratios D{sub 15cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.01), the ratios D{sub 15cm}{sup 3}/D{sub 50%} (Gy) (p = 0.008) for the heart and correlations between plasma levels and V{sub 2Gy} (%) (p = 0.002), the ratios D{sub 1cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.03), and the ratios D{sub 0.5cm{sup 3}}(Gy)/D{sub 50%}(Gy) (p = 0.05) for the ventricle. Conclusions: Patients with left-sided breast cancer show higher values of NT-pro BNP after RT when compared with non-RT-treated matched patients, increasing in correlation with high doses in small volumes of heart and ventricle. The findings of this study show that the most important parameters are not the mean doses but instead the small percentage of organ volumes (heart or ventricle) receiving high dose levels, supporting the notion that the heart behaves as a serial organ.

D'Errico, Maria P., E-mail: patderrico@libero.it [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Grimaldi, Luca [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Petruzzelli, Maria F. [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Gianicolo, Emilio A.L. [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Tramacere, Francesco [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Monetti, Antonio; Placella, Roberto [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Pili, Giorgio [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Andreassi, Maria Grazia; Sicari, Rosa; Picano, Eugenio [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Portaluri, Maurizio [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy)

2012-02-01

197

[Malignant cardiac lymphoma. Diagnosis by echocardiography].  

PubMed

The authors report a case of cardiac malignant non-Hodgkin lymphoma. The initial clinical presentation suggested recurrent angina in a patient who had undergone angioplasty of the left anterior descending artery two years previously. Echocardiography showed severe left ventricular dysfunction with apical and septal akinesia and also allowed visualisation of two oval masses in the right ventricle without dilatation of the right heart chambers. Transoesophageal echocardiography confirmed these abnormal echos which corresponded to tumour invasion of not only the right heart chambers but also the interatrial septum, the left atrial appendage and the descending thoracic aorta. Histological diagnosis of lymphoma was made from an excision biopsy of a mass in the calf muscle. The post-mortem examination confirmed the presence of a highly malignant T-cell non-Hodgkin lymphoma. The patient rapidly deteriorated and died during the first session of chemotherapy. PMID:9587448

Boey, S; Fouda-Omgba, F; Mirode, A; Tribouilloy, C; Quere, J P; Lesbre, J P

1997-12-01

198

Exertional sudden cardiac death in a young athlete with anomalous origin of the left coronary artery from the opposite sinus  

Microsoft Academic Search

An otherwise healthy and fit 18-year-old African-American male was running sprints while trying out for his high school track team when he suddenly developed severe chest discomfort and collapsed. Assessment at the scene revealed no palpable pulse, cardiopulmonary resuscitation was initiated, and emergency medical services were activated. When paramedics arrived on the scene, they noted his cardiac rhythm as ventricular

Erik Wissner; Luis R. Scott; Komandoor Srivathsan; Gregory T. Altemose

199

Cardiac defibrillator implantation via persistent left superior vena cava - sometimes this approach is facile. A case report.  

PubMed

We report a case of persistent left superior vena cava (PLSVC) incidentally recognized during the implantation of a cardioverter-defibrillator. PLSVC is the most common venous anomaly of the thorax and drains into the right atrium. There are a lot of publications reporting success of pacemaker or defibrillator lead implantations via PLSVC. In this article we present the technique of approaching the right ventricle and right atrium via PLSVC; sometimes this method can be as straightforward as the classical way. Therefore, if PLSVC is recognized intra-operatively, we suggest continuing left-sided implantation, and considering a right venous access only in case of failure. PMID:22291750

Bissinger, Andrzej; Bahadori-Esfahani, Fardokht; Lubi?ski, Andrzej

2011-03-08

200

Gender-specific differences of cardiac remodeling in subjects with left ventricular dysfunction: a population-based study  

Microsoft Academic Search

a ¨ Abstract Background: Recent studies suggest that female gender is associated with a lower prevalence and a more benign prognosis of heart failure. In the current population-based study, it was our objective to evaluate the implications of gender on the association between impaired left ventricular (LV) function and mass as well as neurohumoral activation. Methods and results: A total

Andreas Luchner; Ulrich Brockel; Michael Muscholl; Hans-Werner Hense; Angela Doring; Gunter A. J. Riegger; Heribert Schunkert

201

Experience with the Novacor left ventricular assist system as a bridge to cardiac transplantation, including the new wearable system  

Microsoft Academic Search

The three components of the Novacor left ventricular assist system, compact controller, battery, and back-up battery, have been miniaturized in the development of the wearable system. Therefore patients can be fully mobilized receiving mechanical circulatory support while awaiting heart transplantation. Between February 1992 and April 1994 a total of eight patients with decompensated heart failure (6 dilated cardiomyopathy, 1 acute

Herbert O. Vetter; Hans G. Kaulbach; Christoph Schmitz; Andreas Forst; Peter Überfuhr; Eckart Kreuzer; Michael Pfeiffer; Paolo Brenner; Oliver Dewald; Bruno Reichart

1995-01-01

202

Exercise training does not improve cardiac function in compensated or decompensated left ventricular hypertrophy induced by aortic stenosis  

Microsoft Academic Search

There is ample evidence that regular exercise exerts beneficial effects on left ventricular (LV) hypertrophy, remodeling and dysfunction produced by ischemic heart disease or systemic hypertension. In contrast, the effects of exercise on pathological LV hypertrophy and dysfunction produced by LV outflow obstruction have not been studied to date. Consequently, we evaluated the effects of 8weeks of voluntary wheel running

Elza D. van Deel; Martine de Boer; Diederik W. Kuster; Nicky M. Boontje; Patricia Holemans; Karin R. Sipido; Jolanda van der Velden; Dirk J. Duncker

2011-01-01

203

Extra [corrected] pulmonary uptake of Tc-99m-MAA perfusion lung scan as a result of right to left intra cardiac shunt.  

PubMed

Extra pulmonary accumulation of Tc-99m-macroaggregate of albumin (MAA) is rarely seen on perfusion lung scan, and has been reported in less than 4% of a study population of nearly 380 patients. It occurs when the agent bypasses the lungs due to a right to left (R-L) cardiac or pulmonary shunt, when it is shunted to the portal vein before reaching the right atrium and ventricle of the heart, and when the agent is degraded to a submicron particle size. When a pharmaceutical problem is excluded, extra-pulmonary uptake implies unusual hemodynamics with a shunt. A case is reported in which a clinically unsuspected shunt was diagnosed from the lung perfusion scintigraphy. PMID:16767956

Hussain, Riffat; Maseeh-uz-Zaman; Khan, Sohail Abrar; Ahmad, M Nadeem

2006-05-01

204

[Relationship of variability of blood pressure, cardiac sinus rhythm, and structural and functional characteristics of the left ventricular myocardium in elderly and senile patients with arterial hypertension].  

PubMed

The variability of blood pressure (BP), autonomic cardiac sinus rhythm regulation, and myocardial structural and functional characteristics of the left ventricle (LV) was comparatively analyzed in 201 patients aged 65-88 years who had uncomplicated systolic and diastolic and isolated systolic arterial hypertension (SDAH and ISAH, respectively). There was a greater variability of systolic and diastolic BP no matter what the type of arterial hypertension (AH) was. It was ascertained that ISAH was characterized by absolute parasympaticotonia and SDAH was marked by relative sympaticotonia with the involvement of central ergotropic and humoral-and-metabolic mechanisms. In elderly and senile patients, uncomplicated AH was accompanied in 86.6% of cases by LV remodeling, mainly as its concentric hypertrophy (52.7%), characterizing primarily by non-restrictive diastolic dysfunction. There were no significant differences in the types of LV remodeling and diastolic dysfunction in patients with combined AH and ISAH. Moreover, the development of LV remodeling and associated diastolic dysfunction in SDAH was followed by a decrease in the overall variability of cardiac sinus rhythm with a smaller contribution of a segmental link of the parasympathetic portion of the autonomic nervous system and by the development of relative sympaticotonia due to suprasegmental and humoral-and-metabolic influences. PMID:15540416

Nosov, V P; Borovkov, N N; Sal'tseva, M T; Amineva, N V; Koroleva, L Iu

2004-01-01

205

Anesthesia for videoscopic left cardiac sympathetic denervation in children with congenital long QT syndrome and catecholaminergic polymorphic ventricular tachycardia - a case series  

PubMed Central

Summary Objective To describe our experience in the anesthetic management of pediatric patients who have undergone left cardiac sympathetic denervation (LCSD) for congenital long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT). Background Long QT syndrome and CPVT predispose patients to ventricular arrhythmias and sudden death. One treatment option for these patients is LCSD. When these patients present for LCSD or other surgical procedures, anesthetic management is challenging, as many medications may exacerbate QT prolongation. Methods Retrospective review of the electronic medical records of 22 pediatric patients who underwent LCSD between November 2005 and December 2008. Results Six patients (27%) received midazolam as a premedication. Eleven patients (50%) underwent inhalation induction with sevoflurane. Eighty-six percentage received either sevoflurane or isoflurane for maintenance of anesthesia, while the remaining 14% received a propofol infusion. Nine patients (41%) received esmolol infusions intraoperatively, while one patient (4.5%) received a labetalol infusion. Three patients (14%) received lidocaine infusions. No significant cardiac or other events occurred in any of these patients in the perioperative period. Conclusions Important anesthetic considerations in this population include avoidance of sympathetic stimulation, correction of any abnormal electrolytes, and the immediate availability of a defibrillator and magnesium sulfate to treat arrhythmias. Anxious patients may benefit from premedication to reduce sympathetic tone. We have safely used both volatile agents and propofol for induction and maintenance of anesthesia. In our experience, intraoperative infusions of ?-blockers and lidocaine seem to be helpful in reducing arrhythmogenic potential, especially in patients with profound QT prolongation.

KENYON, CHRISTINE A.; FLICK, RANDALL; MOIR, CHRISTOPHER; ACKERMAN, MICHAEL J.; PABELICK, CHRISTINA M.

2012-01-01

206

Dual-enhancement cardiac computed tomography for assessing left atrial thrombus and pulmonary veins before radiofrequency catheter ablation for atrial fibrillation.  

PubMed

Noninvasive imaging that provides anatomic information while excluding intracardiac thrombus would be of significant clinical value for patients referred for catheter ablation of atrial fibrillation (AF). This study assessed the diagnostic performance of a dual-enhancement single-phase cardiac computed tomography (CT) protocol for thrombus and circulatory stasis detection in AF patients before catheter ablation. We studied 101 consecutive symptomatic AF patients (71 men and 30 women; mean age, 61.8 years) who were scheduled to have catheter ablation. All patients had undergone pre-AF ablation CT imaging and transesophageal echocardiography on the same day. CT was performed with prospective electrocardiographic gating, and scanning began 180 seconds after the test bolus. Mean left atrial appendage (LAA)/ascending aorta Hounsfield unit (HU) ratios were measured on CT images. Among the 101 patients, 9 thrombi and 18 spontaneous echo contrasts were detected by transesophageal echocardiography. The overall sensitivity, specificity, positive predictive value, and negative predictive value of CT for the detection of thrombi in the LAA were 89%, 100%, 100%, and 99%, respectively. The mean LAA/ascending aorta HU ratios were significantly different between thrombus and circulatory stasis (0.17 vs 0.33, p = 0.002). Dual-enhancement single-scan cardiac CT is a sensitive modality for detecting and differentiating LAA thrombus and circulatory stasis. PMID:23582630

Hur, Jin; Pak, Hui-Nam; Kim, Young Jin; Lee, Hye-Jeong; Chang, Hyuk-Jae; Hong, Yoo Jin; Choi, Byoung Wook

2013-04-11

207

Normal left ventricular myocardial thickness for middle aged and older subjects with SSFP cardiac MR: The Multi-Ethnic Study of Atherosclerosis  

PubMed Central

Background Increased left ventricular myocardial thickness (LVMT) is a feature of several cardiac diseases. The purpose of this study was to establish standard reference values of normal LVMT with cardiac MR (CMR) and to assess variation with image acquisition plane, demographics and LV function. Methods and Results End-diastolic LVMT was measured on CMR steady-state free precession cine long and short axis images in 300 consecutive participants free of cardiac disease (169 women; 65.6±8.5 years) of the Multi-Ethnic Study of Atherosclerosis cohort. Mean LVMT on short axis images at the mid-cavity level was 5.3±0.9mm and 6.3±1.1mm for women and men, respectively. The average of the maximum LVMT at the mid-cavity for women/men were 7mm/9mm (long axis) and 7mm/8mm (short axis). Mean LVMT was positively associated with weight (0.02mm/kg, p=0.01) and body-surface-area (1.1mm/m2, p<0.001). No relationship was found between mean LVMT and age or height. Greater mean LVMT was associated with lower LV end-diastolic volume (0.01mm/ml, p<0.01), a lower LV end-systolic volume (?0.01mm/ml, p=0.01) and lower LV stroke volume (?0.01mm/ml, p<0.05). LVMT measured on long axis images at the basal and mid-cavity level were slightly greater (by 6% and 10%, respectively) than measurements obtained on short axis images; apical LVMT values on long axis images were 20% less than those on short axis images. Conclusion Normal values for wall thickness are provided for middle-aged and older subjects. Normal LVMT is lower for women than men. Observed values vary depending on the imaging plane for measurement.

Kawel, Nadine; Turkbey, Evrim B.; Carr, J. Jeffrey; Eng, John; Gomes, Antoinette S.; Hundley, W. Gregory; Johnson, Craig; Masri, Sofia C.; Prince, Martin R.; van der Geest, Rob J.; Lima, Joao A. C.; Bluemke, David A.

2012-01-01

208

Left fallopian tube primitive serous adenocarcinoma presenting as a cardiac tamponade - a case report and review of literature.  

PubMed

A 61-year-old woman presented to the emergency room complaining of anterior left thoracic pain and shortness of breath even after minor efforts. Her previous medical history was unremarkable. Pulmonary angiographic tomography showed a moderate bilateral pleural effusion that had collapsed inferior lung lobes, a large pericardial effusion, and several enlarged lymph nodes in the anterior mediastinum. Echocardiogram (ECG) showed a considerable pericardial effusion with some degree of heart function impairment. Pericardiocentesis and thoracocentesis revealed neoplastic cells in both pericardial and pleural fluids. Abdominal and pelvic ultrasound showed a complex cystic mass with a 13-cm diameter located at left adnexal region and another complex cystic tumor with five-cm diameter at right adnexal region, with small amount of peritoneal effusion. Surgical staging was performed. Pathologic diagnosis was primitive left fallopian tube serous adenocarcinoma with peritubal involvement and multiple peritoneal and lymphatic metastases (FIGO Stage IV; TNM pT3c M1). Chemotherapy was initiated. Death occurred 25 months after diagnosis, with secondary dissemination (breast and lung). No recurrence of pericardial effusion was registered after chemotherapy, suggesting a high susceptibility of pericardial metastasis. PMID:23967559

Patrao, L; Sa, J; Fonseca-Moutinho, J A; Castelo-Branco, M; Garcia, H

2013-01-01

209

Right and left ventricular volume measurements in an animal heart model in vitro: first experiences with cardiac MRI at 1.0 T.  

PubMed

The aim of this study was to determine the accuracy in quantifying right and left ventricular volumes using a 1.0-T system and commercially available, standard equipment. For exact comparison of MRI measurements and real volumes we used an animal heart model ex vivo. Eight pig hearts were explanted and prepared by removal of the atria. Aorta and pulmonary truncus were cannulated. Definable volumes were injected into the ventricles. Magnetic resonance imaging was performed at 1.0 T (Gyroscan T10 NT, Philips, Eindhoven, The Netherlands); sequence: fast field echo-echo planar (multishot EPI); body coil; MR software: Cardiac Application Package (Philips). Statistical analysis correlated the real volumes and MR measurements separately for both ventricles and two investigators (SAS, ANOVA). For both ventricles and both investigators the correlation between real volumes and MR measurements was greater than 0.99. There was no significant systematic false estimation for both ventricles. Magnetic resonance imaging at 1.0 T using standard hardware and software equipment enables the quantification of right and left ventricular volumes with high approximation to the real volumes in vitro. There is a clear restriction in translating these data into a clinical application because under experimental conditions no motion-induced artifacts existed. PMID:10756995

Koch, J A; Poll, L W; Godehardt, E; Korbmacher, B; Mödder, U

2000-01-01

210

Construction of a two-parameter empirical model of left ventricle wall motion using cardiac tagged magnetic resonance imaging data  

PubMed Central

Background A one-parameter model was previously proposed to characterize the short axis motion of the LV wall at the mid-ventricle level. The single parameter of this model was associated with the radial contraction of myocardium, but more comprehensive model was needed to account for the rotation at the apex and base levels. The current study developed such model and demonstrated its merits and limitations with examples. Materials and methods The hearts of five healthy individuals were visualized using cardiac tagged magnetic resonance imaging (tMRI) covering the contraction and relaxation phases. Based on the characteristics of the overall dynamics of the LV wall, its motion was represented by a combination of two components - radial and rotational. Each component was represented by a transformation matrix with a time-dependent variable ? or ?. Image preprocessing step and model fitting algorithm were described and applied to estimate the temporal profiles of ? and ? within a cardiac cycle at the apex, mid-ventricle and base levels. During this process, the tagged lines of the acquired images served as landmark reference for comparing against the model prediction of the motion. Qualitative and quantitative analyses were performed for testing the performance of the model and thus its validation. Results The ? and ? estimates exhibited similarities in values and temporal trends once they were scaled by the radius of the epicardium (repi)and plotted against the time scaled by the period of the cardiac cycle (Tcardiac) of each heart measured during the data acquisition. ?/repi peaked at about ?t/Tcardiac=0.4 and with values 0.34, 0.4 and 0.3 for the apex, mid-ventricle and base level, respectively. ?/repi similarly maximized in amplitude at about ?t/Tcardiac=0.4, but read 0.2 for the apex and - 0.08 for the base level. The difference indicated that the apex twisted more than the base. Conclusion It is feasible to empirically model the spatial and temporal evolution of the LV wall motion using a two-parameter formulation in conjunction with tMRI-based visualization of the LV wall in the transverse planes of the apex, mid-ventricle and base. In healthy hearts, the analytical model will potentially allow deriving biomechanical entities, such as strain, strain rate or torsion, which are typically used as diagnostic, prognostic or predictive markers of cardiovascular diseases including diabetes.

2012-01-01

211

Atherosclerotic renal artery stenosis is prevalent in cardiorenal patients but not associated with left ventricular function and myocardial fibrosis as assessed by cardiac magnetic resonance imaging  

PubMed Central

Background Atherosclerotic renal artery stenosis (ARAS) is common in cardiovascular diseases and associated with hypertension, renal dysfunction and/or heart failure. There is a paucity of data about the prevalence and the role of ARAS in the pathophysiology of combined chronic heart failure (CHF) and chronic kidney disease (CKD). We investigated the prevalence in patients with combined CHF/CKD and its association with renal function, cardiac dysfunction and the presence and extent of myocardial fibrosis. Methods The EPOCARES study (ClinTrialsNCT00356733) investigates the role of erythropoietin in anaemic patients with combined CHF/CKD. Eligible subjects underwent combined cardiac magnetic resonance imaging (cMRI), including late gadolinium enhancement, with magnetic resonance angiography of the renal arteries (MRA). Results MR study was performed in 37 patients (median age 74?years, eGFR 37.4?±?15.6?ml/min, left ventricular ejection fraction (LVEF) 43.3?±?11.2%), of which 21 (56.8%) had ARAS (defined as stenosis >50%). Of these 21 subjects, 8 (21.6%) had more severe ARAS >70% and 8 (21.6%) had a bilateral ARAS >50% (or previous bilateral PTA). There were no differences in age, NT-proBNP levels and medication profile between patients with ARAS versus those without. Renal function declined with the severity of ARAS (p?=?0.03), although this was not significantly different between patients with ARAS versus those without. Diabetes mellitus was more prevalent in patients without ARAS (56.3%) against those with ARAS (23.8%) (p?=?0.04). The presence and extent of late gadolinium enhancement, depicting myocardial fibrosis, did not differ (p?=?0.80), nor did end diastolic volume (p?=?0.60), left ventricular mass index (p?=?0.11) or LVEF (p?=?0.15). Neither was there a difference in the presence of an ischemic pattern of late enhancement in patients with ARAS versus those without. Conclusions ARAS is prevalent in combined CHF/CKD and its severity is associated with a decline in renal function. However, its presence does not correlate with a worse LVEF, a higher left ventricular mass or with the presence and extent of myocardial fibrosis. Further research is required for the role of ARAS in the pathophysiology of combined chronic heart and renal failure.

2012-01-01

212

Adult teleost heart expresses two distinct troponin C paralogs: cardiac TnC and a novel and teleost-specific ssTnC in a chamber- and temperature-dependent manner.  

PubMed

The teleost-specific whole genome duplication created multiple copies of genes allowing for subfunctionalization of isoforms. In this study, we show that the teleost cardiac Ca(2+)-binding troponin C (TnC) is the product of two distinct genes: cardiac TnC (cTnC, TnnC1a) and a fish-specific slow skeletal TnC (ssTnC, TnnC1b). The ssTnC gene is novel to teleosts as mammals have a single gene commonly referred as cTnC but which is also expressed in slow skeletal muscle. In teleosts, the data strongly indicate that these are two TnC genes are different paralogs. Because we determined that ssTnC exists across many teleosts but not in basal ray-finned fish (e.g., bichir), we propose that these paralogs are the result of an ancestral tandem gene duplication persisting only in teleosts. Quantification of mRNA levels was used to demonstrate distinct expression localization patterns of the paralogs within the chambers of the heart. In the adult zebrafish acclimated at 28°C, ssTnC mRNA levels are twofold greater than cTnC mRNA levels in the atrium, whereas cTnC mRNA was almost exclusively expressed in the ventricle. Meanwhile, rainbow trout acclimated at 5°C showed cTnC mRNA levels in both chambers significantly greater than ssTnC. Distinct responses to temperature acclimation were also quantified in both adult zebrafish and rainbow trout, with mRNA in both chambers shifting to express higher levels of cTnC in 18°C acclimated zebrafish and 5°C acclimated trout. Possible subfunctionalization of TnC isoforms may provide insight into how teleosts achieve physiological versatility in chamber-specific contractile properties. PMID:23881286

Genge, Christine E; Davidson, William S; Tibbits, Glen F

2013-07-23

213

Longstanding Hyperthyroidism Is Associated with Normal or Enhanced Intrinsic Cardiomyocyte Function despite Decline in Global Cardiac Function  

PubMed Central

Thyroid hormones (THs) play a pivotal role in cardiac homeostasis. TH imbalances alter cardiac performance and ultimately cause cardiac dysfunction. Although short-term hyperthyroidism typically leads to heightened left ventricular (LV) contractility and improved hemodynamic parameters, chronic hyperthyroidism is associated with deleterious cardiac consequences including increased risk of arrhythmia, impaired cardiac reserve and exercise capacity, myocardial remodeling, and occasionally heart failure. To evaluate the long-term consequences of chronic hyperthyroidism on LV remodeling and function, we examined LV isolated myocyte function, chamber function, and whole tissue remodeling in a hamster model. Three-month-old F1b hamsters were randomized to control or 10 months TH treatment (0.1% grade I desiccated TH). LV chamber remodeling and function was assessed by echocardiography at 1, 2, 4, 6, 8, and 10 months of treatment. After 10 months, terminal cardiac function was assessed by echocardiography and LV hemodynamics. Hyperthyroid hamsters exhibited significant cardiac hypertrophy and deleterious cardiac remodeling characterized by myocyte lengthening, chamber dilatation, decreased relative wall thickness, increased wall stress, and increased LV interstitial fibrotic deposition. Importantly, hyperthyroid hamsters demonstrated significant LV systolic and diastolic dysfunction. Despite the aforementioned remodeling and global cardiac decline, individual isolated cardiac myocytes from chronically hyperthyroid hamsters had enhanced function when compared with myocytes from untreated age-matched controls. Thus, it appears that long-term hyperthyroidism may impair global LV function, at least in part by increasing interstitial ventricular fibrosis, in spite of normal or enhanced intrinsic cardiomyocyte function.

Redetzke, Rebecca A.; Gerdes, A. Martin

2012-01-01

214

Left Atrial Myxoma.  

National Technical Information Service (NTIS)

Cardiac myxomas are benign tumors of the heart and arise most commonly from the interatrial septum, typically on the left side. They may grow to be fairly large at presentation, often associated with intracardiac obstruction, embolic events, or constituti...

J. D. Hirsch V. B. Ho

2006-01-01

215

Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.  

PubMed

Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging. PMID:23517485

Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

2013-03-20

216

Exposure chamber  

DOEpatents

An exposure chamber includes an imperforate casing having a fluid inlet at the top and an outlet at the bottom. A single vertical series of imperforate trays is provided. Each tray is spaced on all sides from the chamber walls. Baffles adjacent some of the trays restrict and direct the flow to give partial flow back and forth across the chambers and downward flow past the lowermost pan adjacent a central plane of the chamber.

Moss, Owen R. (Kennewick, WA); Briant, James K. (Pasco, WA)

1983-01-01

217

Metabolomic profiling analysis reveals chamber-dependent metabolite patterns in the mouse heart.  

PubMed

Energy of the cardiac muscle largely depends on fatty acid oxidation. It is known that the atrium and ventricle have chamber-specific functions, structures, gene expressions, and pathologies. The left ventricle works as a high-pressure chamber to pump blood toward the body, and its muscle wall is thicker than those of the other chambers, suggesting that energy utilization in each of the chambers should be different. However, a chamber-specific pattern of metabolism remains incompletely understood. Recently, innovative techniques have enabled the comprehensive analysis of metabolites. Therefore, we aimed to clarify differences in metabolic patterns among the chambers. Male C57BL6 mice at 6 wk old were subject to a comprehensive measurement of metabolites in the atria and ventricles by capillary electrophoresis and mass spectrometry. We found that overall metabolic profiles, including nucleotides and amino acids, were similar between the right and left ventricles. On the other hand, the atria exhibited a distinct metabolic pattern from those of the ventricles. Importantly, the high-energy phosphate pool (the total concentration of ATP, ADP, and AMP) was higher in both ventricles. In addition, the levels of lactate, acetyl CoA, and tricarboxylic acid cycle contents were higher in the ventricles. Accordingly, the activities and/or expression levels of key enzymes were higher in the ventricles to produce more energy. The present study provides a basis for understanding the chamber-specific metabolism underlining pathophysiology in the heart. PMID:23792677

Shimura, Daisuke; Nakai, Gaku; Jiao, Qibin; Osanai, Kota; Kashikura, Kasumi; Endo, Keiko; Soga, Tomoyoshi; Goda, Nobuhito; Minamisawa, Susumu

2013-06-21

218

Local electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy: Retrospective study with 1 year follow up  

PubMed Central

Background Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode local electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response. Methods We conducted a retrospective, single–centre analysis of 161 consecutive patients with heart failure and LBBB or nonspecific intraventricular conduction delay (IVCD) treated with CRT. We routinely intend to implant the LV lead in a region with long QLV. Clinical response to CRT, left ventricular (LV) reverse remodelling (i.e. decrease in LV end-systolic diameter - LVESD ?10%) and reduction in plasma level of NT-proBNP >30% at 12-month post-implant were the study endpoints. We analyzed association between pre-implant variables and the study endpoints. Results Clinical CRT response rate reached 58%, 84% and 92% in the lowest (?105?ms), middle (106-130?ms) and the highest (>130?ms) QLV tertile (p?

2012-01-01

219

Left atrial and ventricular function during dobutamine and glycopyrrolate stress in healthy young and elderly as evaluated by cardiac magnetic resonance.  

PubMed

The aim of this study is to describe phasic volume changes of the left atrium (LA) in healthy young and elderly subjects at rest and during pharmacological stress (PS). LA maximum size is related to cardiovascular mortality. LA has passive, active, and conduit function for left ventricular (LV) filling. We hypothesized that changes in LV compliance from normal aging are reflected in LA volume changes and that PS will augment these differences. We enrolled twenty young (20-30 yr) and twenty elderly (60-70 yr) healthy subjects and measured their LV and LA volumes by cardiac magnetic resonance imaging at rest and during dobutamine and glycopyrrolate stress. We identified LA minimum, maximum, and middiastolic volumes and the volume before atrial contraction. LA emptying volumes were calculated as LA passive and active emptying volumes and LA conduit volume. We also calculated LV peak filling rates (LVPFRs). Both at rest and during PS, LA maximum and minimum volumes were similar in the groups, whereas middiastolic volume was higher in the elderly. During PS, a marked decrease in LA passive emptying function and a corresponding increase in LA active emptying function were seen in the elderly but not in the young. At rest, LVPFR was lower in the elderly, and during PS this difference was augmented. The aging heart has reduced LVPFR, which is reflected in reduced LA passive and compensatory increased LA active volumetric contribution to LV stroke volume. These age-related differences are evident at rest and highly augmented during both dobutamine and glycopyrrolate stress. PMID:23086990

Ahtarovski, Kiril A; Iversen, Kasper K; Lønborg, Jacob T; Madsen, Per L; Engstrøm, Thomas; Vejlstrup, Niels

2012-10-19

220

Off-pump anteroapical aneurysm plication following left ventricular postinfarction aneurysm: effect on cardiac function, clinical status and survival  

PubMed Central

Background In patients with coronary disease and aneurysm, ventricular reconstruction with revascularization is a surgical option. Details of patient selection and optimal surgical technique are still debated. We report our results with off-pump aneurysm plication after ventricular aneurysm with relative wall thinning. Methods We retrospectively reviewed the records of 248 patients who had an operation for postinfarction left ventricular aneurysm. Reconstruction was accomplished by off-pump anteroapical aneurysm plication. The following variables were recorded: preoperative clinical, angiographic and echocardiographic findings and operative procedures. Outcomes were early mortality, long-term survival and poor 5-year result, defined as the need for transplantation or repeated hospitalization for congestive heart failure. Risk factors were pinpointed using the t test and survival curves. Independent risk factors were identified using Cox regression methods. Results Hospital mortality was low (2.0%). Mean follow-up was 5.8 (standard deviation [SD] 3.8) years. Actuarial survival at 1 and 5 years was 94% and 84%. Among the 232 survivors, 200 were in functional class I or II, and the average increase in ejection fraction was 14.0% (SD 3.1%). As determined by multivariable analysis, factors predicting poor outcome were advanced age, ejection fraction less than 0.35, conicity index less than 1, end-systolic volume index greater than 80 mL/m2, advanced New York Heart Association functional class and congestive heart failure. Conclusion Using wall thinning as a criterion for patient selection, the technique of off-pump anteroapical aneurysm plication can be performed with low operative mortality and provides good symptomatic relief and long-term survival.

Huang, Xin-sheng; Gu, Cheng-xiong; Yang, Jun-feng; Wei, Hua; Li, Jing-xing; Zhou, Qi-wen

2013-01-01

221

An algorithm for noninvasive identification of angiographic three-vessel and\\/or left main coronary artery disease in symptomatic patients on the basis of cardiac risk and electron-beam computed tomographic calcium scores  

Microsoft Academic Search

ObjectivesWe sought to model an algorithm for noninvasive identification of angiographically obstructive three-vessel and\\/or left main disease based on conventional cardiac risk assessment and site and extent of coronary calcium determined by electron-beam computed tomography (EBCT).BackgroundSuch an algorithm would greatly facilitate clinical triage in symptomatic patients with no previous diagnosis of coronary artery disease (CAD).MethodsWe examined 291 patients with suspected,

Axel Schmermund; Kent R Bailey; John A Rumberger; Judd E Reed; Patrick F Sheedy; Robert S Schwartz

1999-01-01

222

Exposure chamber  

DOEpatents

A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

Moss, Owen R. (Kennewick, WA)

1980-01-01

223

Pressure overload-induced mild cardiac hypertrophy reduces left ventricular transmural differences in mitochondrial respiratory chain activity and increases oxidative stress  

PubMed Central

Objective: Increased mechanical stress and contractility characterizes normal left ventricular (LV) subendocardium (Endo) but whether Endo mitochondrial respiratory chain complex activities is reduced as compared to subepicardium (Epi) and whether pressure overload-induced LV hypertrophy (LVH) might modulate transmural gradients through increased reactive oxygen species (ROS) production is unknown. Methods: LVH was induced by 6 weeks abdominal aortic banding and cardiac structure and function were determined with echocardiography and catheterization in sham-operated and LVH rats (n = 10 for each group). Mitochondrial respiration rates, coupling, content and ROS production were measured in LV Endo and Epi, using saponin-permeabilized fibers, Amplex Red fluorescence and citrate synthase activity. Results: In sham, a transmural respiratory gradient was observed with decreases in endo maximal oxidative capacity (?36.7%, P < 0.01) and complex IV activity (?57.4%, P < 0.05). Mitochondrial hydrogen peroxide (H2O2) production was similar in both LV layers. Aortic banding induced mild LVH (+31.7% LV mass), associated with normal LV fractional shortening and end diastolic pressure. LVH reduced maximal oxidative capacity (?23.6 and ?33.3%), increased mitochondrial H2O2 production (+86.9 and +73.1%), free radical leak (+27.2% and +36.3%) and citrate synthase activity (+27.2% and +36.3%) in Endo and Epi, respectively. Transmural mitochondrial respiratory chain complex IV activity was reduced in LVH (?57.4 vs. ?12.2%; P = 0.02). Conclusions: Endo mitochondrial respiratory chain complexes activities are reduced compared to LV Epi. Mild LVH impairs mitochondrial oxidative capacity, increases oxidative stress and reduces transmural complex IV activity. Further studies will be helpful to determine whether reduced LV transmural gradient in mitochondrial respiration might be a new marker of a transition from uncomplicated toward complicated LVH.

Kindo, Michel; Gerelli, Sebastien; Bouitbir, Jamal; Charles, Anne-Laure; Zoll, Joffrey; Hoang Minh, Tam; Monassier, Laurent; Favret, Fabrice; Piquard, Francois; Geny, Bernard

2012-01-01

224

Quantification of left ventricular size and function using contrast-enhanced real-time 3D imaging with power modulation: comparison with cardiac MRI.  

PubMed

In patients with optimal images, real-time 3-D echocardiography (RT3DE) allows accurate evaluation of left ventricular (LV) volumes and ejection fraction (EF). However, in patients with poor acoustic windows, lower correlations were reported despite the use of contrast. We hypothesized that power modulation (PM) RT3DE imaging that uses low mechanical indices and provides uniform LV opacification could overcome this problem. Accordingly, we sought to: (i) Test the feasibility of quantification of LV volumes and EF from contrast-enhanced (CE) PM RT3DE images, (ii) validate this technique against cardiac magnetic resonance (CMR) reference and (iii) test its clinical value by quantifying the improvement in accuracy and reproducibility. We studied 20 patients who underwent CMR, harmonic nonenhanced RT3DE and CE PM RT3DE imaging on the same day. All images were analyzed to obtain end-systolic and end-diastolic LV volumes (EDV, ESV) and calculate EF. To determine the reproducibility of each RT3DE technique, imaging was repeated in the same setting by a second sonographer. In addition, patients were divided according to the quality of their RT3DE images into two groups, for which agreement with CMR and reproducibility were calculated separately. CE PM RT3DE imaging improved the accuracy of EDV, ESV and EF measurements in patients with poor acoustic windows without significantly affecting those in patients with optimal images. In addition, CE PM RT3DE imaging improved the reproducibility of the measurements, as reflected by a twofold decrease in intermeasurement variability. Importantly, the variability in CE PM RT3DE-derived volumes and EF was under 10%, irrespective of image quality. This methodology may become the new standard for LV size and function, which will be particularly important in patients with poor acoustic windows or contraindications to CMR. PMID:22906750

Coon, Patrick D; Pollard, Heidi; Furlong, Kathleen; Lang, Roberto M; Mor-Avi, Victor

2012-08-17

225

Cardiac magnetic resonance in a patient with MRI-conditional pacemaker.  

PubMed

An implanted pacemaker is generally considered a contraindication for magnetic resonance imaging (MRI). The increasing number of indications for MRI and the rising prevalence of implanted cardiac pacemakers have prompted the recent development of MRI-conditional pacemaker systems. We present the case of a 68-year-old woman with left ventricular hypertrophy, hypertension, aortic valve stenosis and a family history of cardiac amyloidosis, who developed complete heart block. In view of the foreseeable need for cardiac MRI, an MRI-conditional dual chamber pacemaker was implanted. The MRI scan confirmed moderate left ventricular hypertrophy and aortic valve stenosis, and showed no delayed enhancement suggestive of amyloid heart disease. This case illustrates the feasibility of cardiac MRI in this setting and the usefulness of the recently introduced MRI-conditional pacemaker systems. PMID:23333214

Ferreira, António Miguel; Mendes, Lígia; Soares, Luís; da Graça Correia, Maria; Gil, Victor

2013-01-17

226

Diastolic compliance of the left atrium in man: A determinant of preload of the left ventricle  

Microsoft Academic Search

Summary During the ventricular slow-filling period, both the left atrium and left ventricle fill passively, and their respective internal pressures equalize, becoming evenly elevated. If the diastolic chamber compliance of the left atrium is smaller than that of the left ventricle, we expect the inflowing blood to be distributed more to the left ventricle than to the left atrium during

Toshihiko Nagano; Michio Arakawa; Tsutomu Tanaka; Masato Yamaguchi; Tadatake Takaya; Toshiyuki Noda; Hiroshi Miwa; Kensaku Kagawa; Senri Hirakawa

1989-01-01

227

Comparison of cardiac surgery with left atrial surgical ablation vs. cardiac surgery without atrial ablation in patients with coronary and/or valvular heart disease plus atrial fibrillation: final results of the PRAGUE-12 randomized multicentre study†  

PubMed Central

Aims Surgical ablation procedure can restore sinus rhythm (SR) in patients with atrial fibrillation (AF) undergoing cardiac surgery. However, it is not known whether it has any impact on long-term clinical outcomes. Methods and results This multicentre study randomized 224 patients with AF scheduled for valve and/or coronary surgery: group A (left atrial surgical ablation, n = 117) vs. group B (no ablation, n = 107). The primary efficacy outcome was the SR presence (without any AF episode) during a 24 h electrocardiogram (ECG) after 1 year. The primary safety outcome was the combined endpoint of death/myocardial infarction/stroke/renal failure at 30 days. A Holter-ECG after 1 year revealed SR in 60.2% of group A patients vs. 35.5% in group B (P = 0.002). The combined safety endpoint at 30 days occurred in 10.3% (group A) vs. 14.7% (group B, P = 0.411). All-cause 1-year mortality was 16.2% (A) vs. 17.4% (B, P = 0.800). Stroke occurred in 2.7% (A) vs. 4.3% (B) patients (P = 0.319). No difference (A vs. B) in SR was found among patients with paroxysmal (61.9 vs. 58.3%) or persistent (72 vs. 50%) AF, but ablation significantly increased SR prevalence in patients with longstanding persistent AF (53.2 vs. 13.9%, P < 0.001). Conclusion Surgical ablation improves the likelihood of SR presence post-operatively without increasing peri-operative complications. However, the higher prevalence of SR did not translate to improved clinical outcomes at 1 year. Further follow-ups (e.g. 5-year) are warranted to show any potential clinical benefit which might occur later.

Budera, Petr; Straka, Zbynek; Osmancik, Pavel; Vanek, Tomas; Jelinek, Stepan; Hlavicka, Jan; Fojt, Richard; Cervinka, Pavel; Hulman, Michal; Smid, Michal; Maly, Marek; Widimsky, Petr

2012-01-01

228

Cardiac MRI in Athletes  

Microsoft Academic Search

Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with CMR.\\u000a\\u000aChapter 2 describes our finding that left-right ratios are preserved across all sports

T. Luijkx

2012-01-01

229

IONIZATION CHAMBER  

DOEpatents

This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

Redman, W.C.; Shonka, F.R.

1958-02-18

230

Giant left atrial myxoma mimicking severe mitral valve stenosis and severe pulmonary hypertension.  

PubMed

Myxoma is the most common primary tumor of the heart and can arise in any of the cardiac chambers. This paper reports A 50 -year-old woman without medical history and any cardiovascular risk factors was hospitalized for exertional dyspnea and palpitations from three months and signifiant weight loss. Transthoracic echocardiogram showed a giant left atrial myxoma mobile confined to the left atrium in systole, in diastole the tumor was seen prolapsing across the mitral valve into the left ventricle and partially obstructing it and causing severe functional mitral stenosis with a mean gradient of 21,3 mmHg. Severe pulmonary hypertension was confirmed by Doppler PAPs =137 mmHg. The patient was scheduled for cardiac surgery with good outcome. PMID:23601991

Mouine, Najat N; Asfalou, Ilyass I; Raissouni, Maha M; Benyass, Aatif A; Zbir, El Mehdi

2013-04-19

231

Incremental prognostic value of combining left ventricular lead position and systolic dyssynchrony in predicting long-term survival after cardiac resynchronization therapy.  

PubMed

The efficacy of CRT (cardiac resynchronization therapy) can be affected by a number of factors; however, the prognostic significance of the LV (left ventricular) lead position has not been explored. The aim of the present study was to examine whether a PL (posterolateral) lead position has an additional value to systolic dyssynchrony in predicting a better survival after CRT. Patients (n=134) who received CRT were followed-up for 39+/-24 months. The LV lead position was determined by cine fluoroscopy, and baseline dyssynchrony was assessed by TDI (tissue Doppler imaging). The relationship between the LV lead position/dyssynchrony and mortality was compared using Kaplan-Meier curves, followed by Cox regression analysis. The all-cause and cardiovascular mortalities were 38 and 31% respectively. The presence of dyssynchrony and a PL lead position predicted a lower all-cause mortality (29 compared with 47%; log-rank chi2=5.38, P=0.02) and cardiovascular mortality (21 compared with 41%; log-rank chi2=6.75, P=0.009) than when absent. The all-cause mortality was as high as 62% when patients had neither dyssynchrony nor a PL lead position, but was reduced to 29% when both criteria were present, and was between 45 and 46% when only one criterion was present (chi2=6.79, P=0.01). The corresponding values for cardiovascular mortality were 62% when patients had neither dyssynchrony nor a PL lead position, 36-38% when patients had either dyssynchrony or a PL lead position, and 21% when patients had both criteria present (chi2=9.54, P=0.004). Combining dyssynchrony and a PL lead position independently predicted a lower all-cause morality {HR (hazard ratio), 0.496 [95% CI (confidence interval), 0.278-0.888]; P=0.018} and cardiovascular mortality [HR, 0.442 (95% CI, 0.232-0.844); P=0.013]. In conclusion, the placement of the LV lead at a PL position provides additional value to baseline dyssynchrony in predicting a lower all-cause and cardiovascular mortality during long-term follow-up after CRT. PMID:19335338

Zhang, Qing; Yip, Gabriel W-K; Chan, Yat-Sun; Fung, Jeffrey W-H; Chan, Winnie; Lam, Yat-Yin; Yu, Cheuk-Man

2009-09-14

232

Left ventricular pressure and volume data acquisition and analysis using LabVIEW.  

PubMed

To automate analysis of left ventricular pressure-volume data, we used LabVIEW to create applications that digitize and display data recorded from conductance and manometric catheters. Applications separate data into cardiac cycles, calculate parallel conductance, and calculate indices of left ventricular function, including end-systolic elastance, preload-recruitable stroke work, stroke volume, ejection fraction, stroke work, maximum and minimum derivative of ventricular pressure, heart rate, indices of relaxation, peak filling rate, and ventricular chamber stiffness. Pressure-volume loops can be graphically displayed. These analyses are exported to a text-file. These applications have simplified and automated the process of evaluating ventricular function. PMID:9158920

Cassidy, S C; Teitel, D F

1997-03-01

233

Registration-based segmentation of murine 4D cardiac micro-CT data using symmetric normalization  

NASA Astrophysics Data System (ADS)

Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to ten cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase.

Clark, Darin; Badea, Alexandra; Liu, Yilin; Johnson, G. Allan; Badea, Cristian T.

2012-10-01

234

Registration-based segmentation of murine 4D cardiac micro-CT data using symmetric normalization  

PubMed Central

Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to 10 cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase.

Clark, Darin; Badea, Alexandra; Liu, Yilin; Johnson, G. Allan; Badea, Cristian T.

2013-01-01

235

Exercise-induced ST-segment changes permit prediction of improvement in left ventricular ischemic dysfunction after revascularization: Evaluation with positron emission tomographic measurements of regional myocardial blood flow and cardiac output  

Microsoft Academic Search

Background  Prediction of the recovery of left ventricular (LV) ischemic dysfunction after revascularization is important in patients\\u000a with coronary artery disease (CAD). We investigated whether the improvement in LV ischemic dysfunction after revascularization\\u000a could be predicted preoperatively by exercise-induced ST-segment changes.\\u000a \\u000a \\u000a \\u000a Methods and Results  Regional myocardial blood flow (RMBF) and cardiac output were measured with nitrogen 13-ammonia positron emission tomography\\u000a at rest

Takuya Watanabe; Kenichi Harumi; Tetsuo Michihatas; Osamu Okazaki; Hideyuki Yamanaka; Yasushi Akutsu; Takashi Katagiri

1998-01-01

236

Design and rationale of the PRAGUE-12 trial: a large, prospective, randomized, multicenter trial that compares cardiac surgery with left atrial surgical ablation with cardiac surgery without ablation in patients with coronary and/or valvular heart disease plus atrial fibrillation.  

PubMed

Surgical ablation procedure can restore sinus rhythm (SR) in patients with atrial fibrillation (AF) undergoing cardiac surgery. However, it is not known whether it has any impact on clinical outcomes. There is a need for a randomized trial with long-term follow-up to study the outcome of surgical ablation in patients with coronary and/or valve disease and AF. Patients are prospectively enrolled and randomized either to group A (cardiac surgery with left atrial ablation) or group B (cardiac surgery alone). The primary efficacy outcome is the SR presence (without any AF episode) during a 24-hour electrocardiogram after 1 year. The primary safety outcome is the combined end point of death, myocardial infarction, stroke, and renal failure at 30 days. Long-term outcomes are a composite of total mortality, stroke, bleeding, and heart failure at 1 and 5 years. We finished the enrollment with a total of 224 patients from 3 centers in 2 countries in December 2011. Currently, the incomplete 1-year data are available, and the patients who enrolled first will have their 5-year visits shortly. PRAGUE-12 is the largest study to be conducted so far comparing cardiac surgery with surgical ablation of AF to cardiac surgery without ablation in an unselected population of patients who are operated on for coronary and/or valve disease. Its long-term results will lead to a better recognition of ablation's potential clinical benefits. PMID:23280480

Straka, Zbyn?k; Budera, Petr; Osman?ík, Pavel; Van?k, Tomáš; Hulman, Michal; Smíd, Michal; Malý, Marek; Widimský, Petr

2012-12-24

237

Design and Rationale of the PRAGUE-12 Trial: A Large, Prospective, Randomized, Multicenter Trial That Compares Cardiac Surgery With Left Atrial Surgical Ablation With Cardiac Surgery Without Ablation in Patients With Coronary and/or Valvular Heart Disease Plus Atrial Fibrillation  

PubMed Central

Surgical ablation procedure can restore sinus rhythm (SR) in patients with atrial fibrillation (AF) undergoing cardiac surgery. However, it is not known whether it has any impact on clinical outcomes. There is a need for a randomized trial with long-term follow-up to study the outcome of surgical ablation in patients with coronary and/or valve disease and AF. Patients are prospectively enrolled and randomized either to group A (cardiac surgery with left atrial ablation) or group B (cardiac surgery alone). The primary efficacy outcome is the SR presence (without any AF episode) during a 24-hour electrocardiogram after 1 year. The primary safety outcome is the combined end point of death, myocardial infarction, stroke, and renal failure at 30 days. Long-term outcomes are a composite of total mortality, stroke, bleeding, and heart failure at 1 and 5 years. We finished the enrollment with a total of 224 patients from 3 centers in 2 countries in December 2011. Currently, the incomplete 1-year data are available, and the patients who enrolled first will have their 5-year visits shortly. PRAGUE-12 is the largest study to be conducted so far comparing cardiac surgery with surgical ablation of AF to cardiac surgery without ablation in an unselected population of patients who are operated on for coronary and/or valve disease. Its long-term results will lead to a better recognition of ablation's potential clinical benefits.

Straka, Zbynek; Budera, Petr; Osmancik, Pavel; Vanek, Tomas; Hulman, Michal; Smid, Michal; Maly, Marek; Widimsky, Petr

2013-01-01

238

11. Second floor, northwest chamber, south wall. Former passage to ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Second floor, northwest chamber, south wall. Former passage to southwest chamber (door blocked off on far side) on left; closet on right. - Conner Homestead, House, Epping Road (State Route 101), Exeter, Rockingham County, NH

239

Repair of isolated double-chambered right ventricle.  

PubMed

The finding of a double-chambered right ventricle (DCRV) is exceptionally rare as an isolated anomaly. It is a congenital cardiac anomaly in which the right ventricle is separated into two chambers, a proximal high-pressure chamber and a distal low-pressure chamber, by anomalous muscles or fibrous tissues in the right ventricular cavity. We report the case of a 6-year-old infant who was admitted for growth retardation. The patient was diagnosed with an isolated DCRV without any other associated congenital anomalies. The patient underwent a successful cardiac surgical procedure of enlargement repair; he was discharged in good clinical condition with a normal cardiac function. PMID:23860078

El Kouache, M; Babakhoya, A; Labib, S; El Madi, A; Atmani, S; Harandou, M; Abouabdilah, Y; Hida, M

240

Effects of nisoldipine and\\/or enalapril on left ventricular function and exercise capacity in patients with recent anterior myocardial infarction and mild cardiac dysfunction  

Microsoft Academic Search

Treatment of abnormal remodeling and dysfunction of left ventricle after myocardial infarction is one of the major goals of recent therapeutic interventions. The current study, the Nisoldipine Enalapril Anterior Myocardial Infarction Study pilot investigation, was designed to investigate the effects of 12 weeks of treatment with enalapril or nisoldipine or their combination on left ventricular (LV) function and exercise capacity

Massimo Romano; Stefania Cardei; Elisabetta de Arcangelis; Ida Monteforte; Marianunzia Capaldo; Pietro Muto; Raffaele Marchegiano; Michael Ochan Kilama; Mario Condorelli

1997-01-01

241

Effects of perimortem physical factors associated with death on exogenous ethanol concentrations in cardiac blood.  

PubMed

The purpose of this study was to determine whether perimortem physical factors associated with death affect exogenous ethanol concentrations in cardiac blood. Forty-one autopsies of alcohol-intoxicated decedents with no or little putrefaction were involved. Postmortem intervals ranged from 6 to 96 h at the time of autopsy. Our 41 cases consisted of 17 fire victims, 8 drowned persons, 3 blood-loss patients who underwent unsuccessful cardiopulmonary resuscitation (CPR) for 30-50 min, 3 blood-loss persons without CPR, three non-blood-loss patients who underwent unsuccessful CPR for 5-60 min, and seven people who died of other causes. Ethanol concentrations in right cardiac chamber blood ranged from 0.12 to 4.40 mg/g (mean 1.39 mg/g) in all cases. An excellent correlation was observed between ethanol concentrations in right cardiac chamber blood and femoral venous blood (y=1.01x-0.087, n=38, r2=0.990). The ratios of blood ethanol concentrations in the left to right cardiac chambers were significantly lower in blood-loss decedents with CPR (0.71+/-0.13) than other decedents (0.92+/-0.07-1.06+/-0.06). Two factors, blood-loss and prolonged chest compression under ventilation, might have caused a decrease in blood ethanol concentration in the left cardiac chambers. Postmortem cardiac blood ethanol concentration as well as postmortem femoral venous blood ethanol concentration may usually reflect blood ethanol levels at the time of death when putrefaction is not evident. However, special attention is required for cases that received CPR after massive bleeding. PMID:15946884

Moriya, Fumio; Hashimoto, Yoshiaki; Furumiya, Junichi; Nishioka, Sachie

2005-07-01

242

Cardiac function adaptations in hibernating grizzly bears (Ursus arctos horribilis).  

PubMed

Research on the cardiovascular physiology of hibernating mammals may provide insight into evolutionary adaptations; however, anesthesia used to handle wild animals may affect the cardiovascular parameters of interest. To overcome these potential biases, we investigated the functional cardiac phenotype of the hibernating grizzly bear (Ursus arctos horribilis) during the active, transitional and hibernating phases over a 4 year period in conscious rather than anesthetized bears. The bears were captive born and serially studied from the age of 5 months to 4 years. Heart rate was significantly different from active (82.6 +/- 7.7 beats/min) to hibernating states (17.8 +/- 2.8 beats/min). There was no difference from the active to the hibernating state in diastolic and stroke volume parameters or in left atrial area. Left ventricular volume:mass was significantly increased during hibernation indicating decreased ventricular mass. Ejection fraction of the left ventricle was not different between active and hibernating states. In contrast, total left atrial emptying fraction was significantly reduced during hibernation (17.8 +/- 2.8%) as compared to the active state (40.8 +/- 1.9%). Reduced atrial chamber function was also supported by reduced atrial contraction blood flow velocities and atrial contraction ejection fraction during hibernation; 7.1 +/- 2.8% as compared to 20.7 +/- 3% during the active state. Changes in the diastolic cardiac filling cycle, especially atrial chamber contribution to ventricular filling, appear to be the most prominent macroscopic functional change during hibernation. Thus, we propose that these changes in atrial chamber function constitute a major adaptation during hibernation which allows the myocardium to conserve energy, avoid chamber dilation and remain healthy during a period of extremely low heart rates. These findings will aid in rational approaches to identifying underlying molecular mechanisms. PMID:19940994

Nelson, O Lynne; Robbins, Charles T

2009-11-26

243

Cardiac anatomy revisited  

PubMed Central

In tomorrow's world of clinical medicine, students will increasingly be confronted by anatomic displays reconstructed from tomographically derived images. These images all display the structure of the various organs in anatomical orientation, this being determined in time-honoured fashion by describing the individual in the ‘anatomical position’, standing upright and facing the observer. It follows from this approach that all adjectives used to describe the organs should be related to the three orthogonal planes of the body. Unfortunately, at present this convention is not followed for the heart, even though most students are taught that the so-called ‘right chambers’ are, in reality, in front of their ‘left’ counterparts. Rigorous analysis of the tomographic images already available, along with comparison with dissected hearts displayed in attitudinally correct orientation, calls into question this continuing tendency to describe the heart in terms of its own orthogonal axes, but with the organ positioned on its apex, so that the chambers can artefactually be visualized with the right atrium and right ventricle in right-sided position. Although adequate for describing functional aspects, such as ‘right-to-left’ shunting across intracardiac communications, this convention falls short when used to describe the position of the artery that supplies the diaphragmatic surface of the heart. Currently known as the ‘posterior descending artery’, in reality it is positioned inferiorly, and its blockage produces inferior myocardial infarction. In this review, we extend the concept of describing cardiac structure in attitudinally correct orientation, showing also how access to tomographic images clarifies many aspects of cardiac structure previously considered mysterious and arcane. We use images prepared using new techniques such as magnetic resonance imaging and computerized tomography, and compare them with dissection of the heart made in time-honoured fashion, along with cartoons to illustrate contentious topics. We argue that there is much to gain by describing the components of the heart as seen in the anatomical position, along with all other organs and structures in the body. We recognize, nonetheless, that such changes will take many years to be put into practice, if at all.

Anderson, Robert H; Razavi, Reza; Taylor, Andrew M

2004-01-01

244

Neovascularized myxoma-causing abnormal blood flow in the left atrium diagnosed by transesophageal echocardiography.  

PubMed

Myxomas are the most common primary cardiac tumor, and neovascularization of cardiac myxoma has been shown in previous case reports. However, it is seldom reported that abnormal blood flow spurted from a neovascularized myxoma into the cardiac chamber. In this unusual case report, we present a left atrial myxoma in a 44-year-old woman with atypical angina. Transesophageal echocardiography (TEE) revealed several small blood streams spurting from the surface of massively vascularized myxoma into the left atrium. Coronary angiography showed a feeding artery which arose from the right coronary artery and supplied the left atrial myxoma, with no evidence of coronary artery stenosis. This case demonstrated that TTE might be helpful for confirming the neovascularization of myxoma in the left atrium and finding the abnormal blood flow that spurts from the neovascularized myxoma. We speculate that the abnormal blood flow spurting from the neovascularized myxoma into the left atrium may have caused a coronary steal phenomenon thus resulting in myocardial ischemia. PMID:23002715

Wang, Xiaobing; Ren, Weidong; Yang, Jun

2012-09-25

245

Temporal effect of Guanxin No. 2 on cardiac function, blood viscosity and angiogenesis in rats after long-term occlusion of the left anterior descending coronary artery  

Microsoft Academic Search

AimCardiac infarction is one of the main causes of death in both developing and developed countries over past decades. Currently available approaches for treating patients with this disease are not satisfactory. Traditional Chinese medicines have been increasingly paid attention to. The aim of this study was to characterize the dynamic protective effects of Guanxin No. 2 decoction (GX II) on

Xiaowei Zeng; Haibo He; Jun Yang; Xianzhe Yang; Limao Wu; Jun Yu; Lianda Li

2008-01-01

246

Color-coded measures of myocardial velocity throughout the cardiac cycle by tissue Doppler imaging to quantify regional left ventricular function  

Microsoft Academic Search

TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 ± 5 years and 12 patients with heart disease aged 62 ± 17 years were studied with a prototype TDI system. TDI M-mode

John Gorcsan; Vijay K. Gulati; William A. Mandarino; William E. Katz

1996-01-01

247

Pertinent reportable incidental cardiac findings on chest CT without electrocardiography gating: review of 268 consecutive cases.  

PubMed

BackgroundPertinent reportable cardiac findings on non-electrocardiography (ECG)-gated chest CT examinations have become easier to detect given recent advancements in multidetector CT technology. However, those findings are easily overlooked on routine chest CT without ECG gating given residual inherent cardiac motion artifact and non-cardiac indications.PurposeTo describe and quantify the types of pertinent reportable cardiac findings that can be detected on chest CT examinations without ECG gating and evaluate how often they were reported.Material and MethodsTwo radiologists retrospectively reviewed (blinded to the original interpretation) 268 consecutive routine adult chest CT examinations without ECG gating for the presence of pertinent reportable cardiac findings. Retrospective interpretations were then compared with the original radiological reports.ResultsOne hundred and sixty-three patients (61%) had pertinent reportable cardiac findings. The findings encountered included: coronary artery disease (n = 131; 80.0%), coronary artery bypass grafts (n = 10; 6.1%), left ventricular aneurysm (n = 1; 0.6%), valve calcification (n = 131; 80.0%), valve repair/replacement (n = 5; 3.1%), pericardial effusion (n = 33; 20.2%), left atrial appendage thrombus (n = 1; 0.6%), cardiac mass (n = 1; 0.6%), and cardiac chamber enlargement (n = 29; 17.8%). On the original radiological reports 22.3% of the pertinent reportable cardiac findings, detected by the two radiologists retrospectively, were not reported.ConclusionDetection of pertinent reportable cardiac findings on routine chest CT examinations without ECG gating is possible. The high volume of chest CT examinations without ECG gating represents an opportunity for radiologists to comment on the presence or absence of cardiac disease which may influence future clinical decisions. PMID:23436832

Choy, Garry; Kröpil, Patric; Scherer, Axel; El-Sherief, Ahmed H; Chung, Jonathan; Rojas, Carlos A; Abbara, Suhny

2013-02-23

248

Cardiac Involvement in Primary Myopathies  

Microsoft Academic Search

Simultaneous or temporarily staggered affection of both the skeletal as well as the cardiac muscle (cardiac involvement, CI) is a frequent finding in primary myopathies (MPs). CI leads to impulse generation defects, impulse conduction defects, thickened myocardium, left ventriculalr hypertrabeculation, dilatation of the cardiac cavities, secondary valve insufficiency, reduction of coronary vasodilative reserve, intracardial thrombus formation, and heart failure with

J. Finsterer; C. Stöllberger

2000-01-01

249

Acute pressure overload of the right ventricle. Comparison of two models of right-left shunt. Pulmonary artery to left atrium and right atrium to left atrium: experimental study  

PubMed Central

Abtract Background In right ventricular failure (RVF), an interatrial shunt can relieve symptoms of severe pulmonary hypertension by reducing right ventricular preload and increasing systemic flow. Using a pig model to determine if a pulmonary artery - left atrium shunt (PA-LA) is better than a right atrial - left atrial shunt (RA-LA), we compared the hemodynamic effects and blood gases between the two shunts. Methods Thirty, male Large White pigs weighting in average 21.3 kg ± 0.7 (SEM) were divided into two groups (15 pigs per group): In group 1, banding of the pulmonary artery and a pulmonary artery to left atrium shunt with an 8 mm graft (PA-LA) was performed and in group 2 banding of the pulmonary artery and right atrial to left atrial shunt (RA-LA) with a similar graft was performed. Hemodynamic parameters and blood gases were measured from all cardiac chambers in 10 and 20 minutes, half and one hour interval from the baseline (30 min from the banding). Cardiac output and flow of at the left anterior descending artery was also monitored. Results In both groups, a stable RVF was generated. The PA-LA shunt compared to the RA-LA shunt has better hemodynamic performance concerning the decreased right ventricle afterload, the 4 fold higher mean pressure of the shunt, the better flow in left anterior descending artery and the decreased systemic vascular resistance. Favorable to the PA-LA shunt is also the tendency - although not statistically significant - in relation to central venous pressure, left atrial filling and cardiac output. Conclusion The PA-LA shunt can effectively reverse the catastrophic effects of acute RVF offering better hemodynamic characteristics than an interatrial shunt.

2011-01-01

250

Cardiac stem cells delivered intravascularly traverse the vessel barrier, regenerate infarcted myocardium, and improve cardiac function  

PubMed Central

The ability of cardiac stem cells (CSCs) to promote myocardial repair under clinically relevant conditions (i.e., when delivered intravascularly after reperfusion) is unknown. Thus, rats were subjected to a 90-min coronary occlusion; at 4 h after reperfusion, CSCs were delivered to the coronary arteries via a catheter positioned into the aortic root. Echocardiographic analysis showed that injection of CSCs attenuated the increase in left ventricular (LV) end-diastolic dimensions and impairment in LV systolic performance at 5 weeks after myocardial infarction. Pathologic analysis showed that treated hearts exhibited a smaller increase in LV chamber diameter and volume and a higher wall thickness-to-chamber radius ratio and LV mass-to-chamber volume ratio. CSCs induced myocardial regeneration, decreasing infarct size by 29%. A diploid DNA content and only two chromosomes 12 were found in new cardiomyocytes, indicating that cell fusion did not contribute to tissue reconstitution. In conclusion, intravascular injection of CSCs after reperfusion limits infarct size, attenuates LV remodeling, and ameliorates LV function. This study demonstrates that CSCs are effective when delivered in a clinically relevant manner, a clear prerequisite for clinical translation, and that these beneficial effects are independent of cell fusion. The results establish CSCs as candidates for cardiac regeneration and support an approach in which the heart's own stem cells could be collected, expanded, and stored for subsequent therapeutic repair.

Dawn, Buddhadeb; Stein, Adam B.; Urbanek, Konrad; Rota, Marcello; Whang, Brian; Rastaldo, Raffaella; Torella, Daniele; Tang, Xian-Liang; Rezazadeh, Arash; Kajstura, Jan; Leri, Annarosa; Hunt, Greg; Varma, Jai; Prabhu, Sumanth D.; Anversa, Piero; Bolli, Roberto

2005-01-01

251

Echocardiography of the normal camel (Camelus dromedaries) heart: technique and cardiac dimensions  

PubMed Central

Background Echocardiography and intra-cardiac dimensions have not previously been reported in adult camels despite its potential application for medical purpose. The aim of this study was to describe the results of a prospective study, aiming to report normal cardiac appearance and normal chamber dimensions in adult camels (Camelus dromedarius). Results On the right side, when the probe was placed in the 5th or 4th intercostal space (ICS), the caudal long-axis four-chamber view of the ventricles, atria, and the interventricular septum was obtained. Placing the probe slightly more cranially in the 4th ICS, the caudal long-axis four-chamber view and the caudal long-axis view of the left ventricular outflow tract (LVOT) were imaged. In 7 camels, a hybrid view between a “four-chamber” and “LVOT view” was imaged from the same position. The short-axis view of the ventricles was obtained in the 4th ICS where the transducer was rotated between 0° and 25°. Placement of the transducer in the 3rd ICS allowed visualisation of the right ventricular outflow tract (RVOT). On the left side, when the probe was placed in the 5th or 4th ICS, a four-chamber view was obtained. The LVOT is imaged in the 4th ICS and the RVOT was seen from the 3rd ICS. Conclusions This study showed that it is possible to obtain good-quality echocardiograms in adult camels and provide normal cardiac dimensions. This study could be used as a reference for further studies concerning camels with cardiac diseases.

2012-01-01

252

Cardiac resynchronization therapy  

Microsoft Academic Search

Summary  BACKGROUND: Cardiac resynchronization therapy (CRT) by pacing the left and right ventricles improves symptoms and functional status in patients with left ventricular dysfunction, congestive heart failure and ventricular conduction disturbances. METHODS: Review of the recent literature. RESULTS: The results of several studies have shown the benefit of CRT in a subpopulation of patients with congestive heart failure. In the majority

G. Prenner; S. Gabor; M. Tripolt; M. Schweiger; K. H. Tscheliessnigg; A. Wasler

2004-01-01

253

Left regional cardiac perfusion in vitro with platelet-activating factor, norepinephrine and K+ reveals that ischaemic arrhythmias are caused by independent effects of endogenous 'mediators' facilitated by interactions, and moderated by paradoxical antagonism  

PubMed Central

Various putative drug targets for suppression of ischaemia-induced ventricular fibrillation (VF) have been proposed, but therapeutic success in the suppression of sudden cardiac death (SCD) has been disappointing. Platelet-activating factor (PAF) is a known component of the ischaemic milieu. We examined its arrhythmogenic activity, and its interaction with two other putative mediators, norepinephrine and K+, using an ischaemia-free in vitro heart bioassay, and a specific PAF antagonist (BN-50739). PAF (0.1–100 nmol) was administered selectively to the left coronary bed of rat isolated hearts using a specially designed catheter. In some hearts, PAF was administered to the left coronary bed during concomitant regional perfusion with norepinephrine and/or K+. In separate studies, PAF accumulation in the perfused cardiac tissue was evaluated using 3H-PAF. PAF evoked ventricular arrhythmias concentration-dependently (P<0.05). It also widened QT interval and reduced coronary flow selectively in the PAF-exposed left coronary bed (both P<0.05). Two exposures of hearts to PAF were necessary to evoke the QT and rhythm effects. The PAF-induced arrhythmias and coronary vasoconstriction were partially suppressed by the PAF antagonist BN-50739 (10 ?M), although BN-50739 itself widened QT interval. K+ (8 and 15 mM) unexpectedly antagonised the arrhythmogenic effects of PAF without itself eliciting arrhythmias (P<0.05). Norepinephrine (0.1 ?M) had little or no effect on the actions of PAF, while failing to evoke arrhythmias itself. Nevertheless, the combination of 15 mM K+ and 0.1 ?M norepinephrine evoked arrhythmias of a severity similar to arrhythmias evoked by PAF alone, without adding to or diminishing the arrhythmogenic effects of PAF. 3H-PAF accumulated in the cardiac tissue, with 43±5% still present 5 min after bolus administration, accounting for the need for two exposures of the heart to PAF for evocation of arrhythmias. Thus, PAF, by activating specific receptors in the ventricle, can be expected to contribute to arrhythmogenesis during ischaemia. However, its interaction with other components of the ischaemic milieu is complex, and selective block of its actions (or its accumulation) in the ischaemic milieu is alone unlikely to reduce VF/SCD.

Baker, Kathryn E; Curtis, Michael J

2004-01-01

254

Increased Potency of Cardiac Stem Cells Compared with Bone Marrow Mesenchymal Stem Cells in Cardiac Repair  

PubMed Central

Whereas cardiac-derived c-kit+ stem cells (CSCs) and bone marrow-derived mesenchymal stem cells (MSCs) are undergoing clinical trials testing safety and efficacy as a cell-based therapy, the relative therapeutic and biologic efficacy of these two cell types is unknown. We hypothesized that human CSCs have greater ability than MSCs to engraft, differentiate, and improve cardiac function. We compared intramyocardial injection of human fetal CSCs (36,000) with two doses of adult MSCs (36,000 and 1,000,000) or control (phosphate buffered saline) in nonobese diabetic/severe combined immune deficiency mice after coronary artery ligation. The myocardial infarction-induced enlargement in left ventricular chamber dimensions was ameliorated by CSCs (p < .05 for diastolic and systolic volumes), as was the decline in ejection fraction (EF; p < .05). Whereas 1 × 106 MSCs partially ameliorated ventricular remodeling and improved EF to a similar degree as CSCs, 36,000 MSCs did not influence chamber architecture or function. All cell therapies improved myocardial contractility, but CSCs preferentially reduced scar size and reduced vascular afterload. Engraftment and trilineage differentiation was substantially greater with CSCs than with MSCs. Adult-cultured c-kit+CSCs were less effective than fetal, but were still more potent than high-dose MSCs. These data demonstrate enhanced CSC engraftment, differentiation, and improved cardiac remodeling and function in ischemic heart failure. MSCs required a 30-fold greater dose than CSCs to improve cardiac function and anatomy. Together, these findings demonstrate a greater potency of CSCs than bone marrow MSCs in cardiac repair.

Oskouei, Behzad N.; Lamirault, Guillaume; Joseph, Chacko; Treuer, Adriana V.; Landa, Stephanie; Da Silva, Jose; Hatzistergos, Konstantinos; Dauer, Marc; Balkan, Wayne; McNiece, Ian

2012-01-01

255

Increased potency of cardiac stem cells compared with bone marrow mesenchymal stem cells in cardiac repair.  

PubMed

Whereas cardiac-derived c-kit(+) stem cells (CSCs) and bone marrow-derived mesenchymal stem cells (MSCs) are undergoing clinical trials testing safety and efficacy as a cell-based therapy, the relative therapeutic and biologic efficacy of these two cell types is unknown. We hypothesized that human CSCs have greater ability than MSCs to engraft, differentiate, and improve cardiac function. We compared intramyocardial injection of human fetal CSCs (36,000) with two doses of adult MSCs (36,000 and 1,000,000) or control (phosphate buffered saline) in nonobese diabetic/severe combined immune deficiency mice after coronary artery ligation. The myocardial infarction-induced enlargement in left ventricular chamber dimensions was ameliorated by CSCs (p < .05 for diastolic and systolic volumes), as was the decline in ejection fraction (EF; p < .05). Whereas 1 × 10(6) MSCs partially ameliorated ventricular remodeling and improved EF to a similar degree as CSCs, 36,000 MSCs did not influence chamber architecture or function. All cell therapies improved myocardial contractility, but CSCs preferentially reduced scar size and reduced vascular afterload. Engraftment and trilineage differentiation was substantially greater with CSCs than with MSCs. Adult-cultured c-kit(+)CSCs were less effective than fetal, but were still more potent than high-dose MSCs. These data demonstrate enhanced CSC engraftment, differentiation, and improved cardiac remodeling and function in ischemic heart failure. MSCs required a 30-fold greater dose than CSCs to improve cardiac function and anatomy. Together, these findings demonstrate a greater potency of CSCs than bone marrow MSCs in cardiac repair. PMID:23197758

Oskouei, Behzad N; Lamirault, Guillaume; Joseph, Chacko; Treuer, Adriana V; Landa, Stephanie; Da Silva, Jose; Hatzistergos, Konstantinos; Dauer, Marc; Balkan, Wayne; McNiece, Ian; Hare, Joshua M

2012-02-07

256

Chamber transport  

SciTech Connect

Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

OLSON,CRAIG L.

2000-05-17

257

Mice expressing L345P mutant desmin exhibit morphological and functional changes of skeletal and cardiac mitochondria.  

PubMed

Desmin mutations underlie inherited myopathies/cardiomyopathies with varying severity and involvement of the skeletal and cardiac muscles. We developed a transgenic mouse model expressing low level of the L345P desmin mutation (DESMUT mice) in order to uncover changes in skeletal and cardiac muscles caused by this mutation. The most striking ultrastructural changes in muscle from DESMUT mice were mitochondrial swelling and vacuolization. The mitochondrial Ca(2+) level was significantly increased in skeletal and cardiac myocytes from DESMUT mice compared to wild type cells during and after contractions. In isolated DESMUT soleus muscles, contractile function and recovery from fatigue were impaired. A SHIRPA screening test for neuromuscular performance demonstrated decreased motor function in DESMUT compared to WT mice. Echocardiographic changes in DESMUT mice included left ventricular wall hypertrophy and a decreased left ventricular chamber dimension. The results imply that low levels of L345P desmin acts, at least partially, by a dominant negative effect on mitochondria. PMID:18563598

Kostareva, Anna; Sjöberg, Gunnar; Bruton, Joseph; Zhang, Shi-Jin; Balogh, Johanna; Gudkova, Alexandra; Hedberg, Birgitta; Edström, Lars; Westerblad, Håkan; Sejersen, Thomas

2008-06-19

258

Biomechanics of early cardiac development.  

PubMed

Biomechanics affect early cardiac development, from looping to the development of chambers and valves. Hemodynamic forces are essential for proper cardiac development, and their disruption leads to congenital heart defects. A wealth of information already exists on early cardiac adaptations to hemodynamic loading, and new technologies, including high-resolution imaging modalities and computational modeling, are enabling a more thorough understanding of relationships between hemodynamics and cardiac development. Imaging and modeling approaches, used in combination with biological data on cell behavior and adaptation, are paving the road for new discoveries on links between biomechanics and biology and their effect on cardiac development and fetal programming. PMID:22760547

Goenezen, Sevan; Rennie, Monique Y; Rugonyi, Sandra

2012-07-04

259

Age and gender-specific differences in left and right ventricular cardiac function and mass determined by cine magnetic resonance imaging  

Microsoft Academic Search

.   We examined possible age- and gender-specific differences in the function and mass of left (LV) and right (RV) ventricles\\u000a in 36 healthy volunteers using cine gradient-recalled echo magnetic resonance imaging. Subjects were divided into four groups\\u000a (nine men and nine women in each): men aged under 45 years (32 ± 7), women aged under 45 (27 ± 6), men

J. Sandstede; C. Lipke; M. Beer; S. Hofmann; T. Pabst; W. Kenn; S. Neubauer; D. Hahn

2000-01-01

260

Warped-average template technique to track on a cycle-by-cycle basis the cardiac filling phases on left ventricular volume  

Microsoft Academic Search

The dynamic time warping approach is utilised to obtain a template from the left ventricular volume signal. The technique, by performing shrinking and enlarging of the temporal axes of two waveforms, indicates the best non-linear alignment between them. In this application this technique is used to track on a cycle-by-cycle basis the diastasis onset and offset thus allowing one to

E. G. Caiani; A. Porta; G. Baselli; M. Turiel; S. Muzzupappa; F. Pieruzzi; C. Crema; A. Malliani; S. Cerutti

1998-01-01

261

Cardiac sympathetic denervation does not change the load dependence of the left ventricular end-systolic pressure\\/volume relationship in dogs  

Microsoft Academic Search

It has been shown that in the intact canine heart the left-ventricular end-systolic pressure\\/volume relation (ESPVR) depends on loading conditions: an increase in arterial vascular resistance causes a leftwards shift and a steeper slope of the ESPVR, suggesting an increased inotropic state. Our purpose was to investigate the possible contribution of the sympathetic nervous system to this load sensitivity of

Inger B. Schipper; Paul Steendijk; Robert J. M. Klautz; Enno T. van der Velde; Jan Baan

1993-01-01

262

Drift Chamber with Multiwire Signal Element and Large Drift GAP.  

National Technical Information Service (NTIS)

A drift chamber with a multiwire signal element is described. The chamber can simultaneously measure particle track and determine left-right ambiguity. The operational characteristics of the chamber with a drift gap of 25 cm and wire length of 20 cm, work...

N. I. Bozhko A. A. Borisov A. S. Vovenko V. Y. Glebov A. I. Mukhin

1977-01-01

263

Point-of-care screening for left ventricular hypertrophy and concentric geometry using hand-held cardiac ultrasound in hypertensive patients  

PubMed Central

Background: The introduction of the hand-held cardiac ultrasound (HCU) may potentially increase detection of LV hypertrophy in hypertensive patients. However, whether point-of-care screening for LV hypertrophy and concentric LV geometry by HCU in hypertensive patients is feasible and comparable to that of standard state-of-the-art echocardiography (SE) evaluation remains to be elucidated. Methods and Results: Accordingly, one hundred consecutive patients (66 female, mean age=58±13 years, 32% African-American, mean body mass index=31±8 kg/m2) with the diagnosis of hypertension underwent both HCU and SE examinations in tandem. A cardiology fellow-in-training performed the HCU exam while a cardiac sonographer performed the SE. 37% of hypertensive patients had electrocardiographic LV hypertrophy by Sokolow-Lyon or Cornell voltage criteria. Mean LV mass was 210±42 g with the HCU and 209±40 g with SE. Mean relative wall thickness was 0.45±0.05 by the HCUD and 0.44±0.05 by SE. There was excellent correlation between LV mass and relative wall thickness measurements by HCU and SE (r=0.985, SEE=6.8 g and r=0.762, SEE=0.33, respectively, both p<0.001). The prevalence of LV hypertrophy using prognostically-validated partition values for LV mass/height2.7 of 46.7 and 49.2 g/m2.7 in women and men, respectively was 76% by HCU and 78% by SE (p=NS), with excellent agreement (92%, ?=0.774, p<0.001). Agreement for detection of concentric LV geometry (relative wall thickness>0.43) was also excellent (88%, ? =0.756, p<0.001). Agreement for LV hypertrophy and concentric geometry detection between the cardiology fellow-in-training and sonographer was excellent (? =0.786, p<0.001). Conclusion: Point-of-care screening for LV hypertrophy and concentric LV geometry by HCU is feasible and correlates very well with that of SE. HCU may allow for immediate point-of-care assessment and treatment of cardiac target organ damage in hypertensive patients.

Stoica, Roxana; Heller, Eliot N; Bella, Jonathan N

2011-01-01

264

The developing pulmonary veins and left atrium: implications for ablation strategy for atrial fibrillation.  

PubMed

The majority of cases of atrial fibrillation (AF) are the result of triggers originating in the area of the pulmonary veins. The reason for the predilection for that area remains unclear. We sought to examine the different mechanisms responsible for this observation through an extensive search of the medical literature, examining the development of the pulmonary veins, genetics of AF and left to -right cardiac chamber differentiation. Results confirm that the LAA is anatomically and embryologically different from other areas of the atrial walls and develops under distinct genetic and transcriptional pathways. Findings support an ablation strategy whose primary focus should be the creation of a 'box' lesion set, plus additional lines to prevent propagation to the left atrial appendage, the isthmus of the left atrium and the right atrium are likely to be more effective than simple pulmonary vein isolation. PMID:23447471

Sherif, Hisham M F

2013-02-27

265

Early Impairment of Transmural Principal Strains in the Left Ventricle Wall Following Short-Term, High Fat Feeding of Mice Predisposed to Cardiac Steatosis  

PubMed Central

Background Myocardial lipid accumulation precedes some cardiomyopathies, but little is known of concurrent effects on ventricular mechanics. We tested the hypothesis that intramyocardial lipid accumulation, during short term high fat diet (HFD), affects 2-D strains in the heart. We examined hearts of nontransgenic (NTG) mice and transgenic mice predisposed to elevated triacylglyceride (TAG) storage linked to low-level overexpression of PPAR?. Methods and Results Myocardial lipid and transmural, principal strains E1 and E2 were determined in vivo with 1H MRS/MRI before and after 2 weeks of HFD in both PPAR? and NTG littermate mice. Baseline lipid was elevated in PPAR? over NTG. HFD increased mobile lipid by 174% in NTG (P<0.05) and 79% in PPAR? (P<0.05). After HFD, lipid and TAG were higher in PPAR? versus NTG, by 63% and 81%, respectively. However, TAG in PPAR? after HFD was similar to TAG in PPAR? on regular diet, suggesting that the MRS signal from lipid is not exclusive to TAG. Only at the highest lipid contents, achieved in PPAR?, were strains affected. Endocardial strain was most compromised, with a negative correlation to lipid (P<0.05), Conclusions Short term high fat diet elevated myocardial lipid measures via MRS which became dissociated from TAG content in hearts predisposed to cardiac steatosis. The increased lipid was associated with concurrent, transmural reductions in E1 and E2 strains across the LV wall. Strains were attenuated at the highest levels of lipid accumulation suggesting a threshold response. Thus, 2-D strains are impaired early and without LV diastolic dysfunction due to cardiac steatosis.

Hankiewicz, Janusz H.; Banke, Natasha H.; Farjah, Mariam; Lewandowski, E. Douglas

2011-01-01

266

Comparison of methods for determining absolute left ventricular volumes from radionuclide ventriculography  

SciTech Connect

Several radionuclide techniques have been used in routine clinical nuclear medicine practice as a means of quantitating left ventricular chamber volumes in man. Despite wide use and availability of the different techniques, however, there has not been a thorough comparison of radionuclide and contrast angiographic measurements performed in the same patients in close temporal proximity. Accordingly, in order to validate traditional methods of ventricular volume measurement, we have performed contrast ventriculography followed immediately (upon return of baseline hemodynamics) by gated radionuclide ventriculography in 34 patients undergoing diagnostic cardiac catheterization. Absolute left ventricular end-diastolic volumes were determined from single-plane, right anterior oblique, end-diastolic contrast silhouettes using a standard area-length method. Radionuclide ventriculographic volumes were determined by three methods: planimetry (32 patients), counts-based (19 patients), and thermodilution stroke volume/radionuclide ejection fraction (32 patients). With planimetry, an area-length method was used in which the modified left anterior oblique left ventricular image was assumed to be a prolate ellipsoid whose volume can be determined by measuring surface area and the ventricular long axis. With the counts-based technique, a blood sample was drawn at the midpoint of the radionuclide ventriculogram acquisition and counted with a gamma camera with appropriate attenuation factor correction. With the thermodilution stroke volume/radionuclide ejection fraction technique, the left ventricular stroke volume was determined by dividing thermodilution cardiac output by the heart rate.

Warren, S.E.; McKay, R.G.; Aroesty, J.M.; Heller, G.V.; Kolodny, G.M.; Royal, H.D.

1987-01-01

267

Canadian Cardiovascular Society focused position statement update on assessment of the cardiac patient for fitness to drive: fitness following left ventricular assist device implantation.  

PubMed

There have been significant advances in mechanical circulatory support during the past several years. Older pulsatile models of left ventricular assist devices (LVADs) (also known as VADs) have shown improved outcomes compared with medical therapy but have had limited durability and significant morbidity associated with their use. For this reason, Canadian Cardiovascular Society 2003 guidelines recommended permanent cessation of driving in these patients (for both private and commercial vehicle operation). However, recent advances with newer, continuous-flow devices have resulted in much lower rates of device-related complications and greater use of these devices for destination therapy. The majority of patients now are discharged home and lead active lives subsequently. Based on new evidence applied to the Society's "Risk of Harm" formula, it has been determined that patients with continuous-flow devices who are doing well 2 months post implantation are fit to hold noncommercial class drivers' licenses. PMID:22342270

Baskett, Roger; Crowell, Richard; Freed, Darren; Giannetti, Nadia; Simpson, Christopher S

2012-02-17

268

Rationale and design of the Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research Trial (MANTICORE 101 - Breast): a randomized, placebo-controlled trial to determine if conventional heart failure pharmacotherapy can prevent trastuzumab-mediated left ventricular remodeling among patients with HER2+ early breast cancer using cardiac MRI  

PubMed Central

Background MANTICORE 101 - Breast (Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research) is a randomized trial to determine if conventional heart failure pharmacotherapy (angiotensin converting enzyme inhibitor or beta-blocker) can prevent trastuzumab-mediated left ventricular remodeling, measured with cardiac MRI, among patients with HER2+ early breast cancer. Methods/Design One hundred and fifty-nine patients with histologically confirmed HER2+ breast cancer will be enrolled in a parallel 3-arm, randomized, placebo controlled, double-blind design. After baseline assessments, participants will be randomized in a 1:1:1 ratio to an angiotensin-converting enzyme inhibitor (perindopril), beta-blocker (bisoprolol), or placebo. Participants will receive drug or placebo for 1 year beginning 7 days before trastuzumab therapy. Dosages for all groups will be systematically up-titrated, as tolerated, at 1 week intervals for a total of 3 weeks. The primary objective of this randomized clinical trial is to determine if conventional heart failure pharmacotherapy can prevent trastuzumab-mediated left ventricular remodeling among patients with HER2+ early breast cancer, as measured by 12 month change in left ventricular end-diastolic volume using cardiac MRI. Secondary objectives include 1) determine the evolution of left ventricular remodeling on cardiac MRI in patients with HER2+ early breast cancer, 2) understand the mechanism of trastuzumab mediated cardiac toxicity by assessing for the presence of myocardial injury and apoptosis on serum biomarkers and cardiac MRI, and 3) correlate cardiac biomarkers of myocyte injury and extra-cellular matrix remodeling with left ventricular remodeling on cardiac MRI in patients with HER2+ early breast cancer. Discussion Cardiac toxicity as a result of cancer therapies is now recognized as a significant health problem of increasing prevalence. To our knowledge, MANTICORE will be the first randomized trial testing proven heart failure pharmacotherapy in the prevention of trastuzumab-mediated cardiotoxicity. We expect the findings of this trial to provide important evidence in the development of guidelines for preventive therapy. Trial Registration ClinicalTrials.gov: NCT01016886

2011-01-01

269

Primary cardiac osteosarcoma  

Microsoft Academic Search

Primary cardiac neoplasms are an infrequent disease, as most of the tumors arising in the heart are metastatic. Between the\\u000a malignant tumors, sarcomas are the most frequent ones, accounting for at least 95% of them. We report the case of a 70-year\\u000a old woman, diagnosed of primary cardiac osteosarcoma arising in the left atrium. Although complete excision of the tumor

María López; Álvaro Pinto; Víctor Moreno; Marta Díaz; Manuel González Barón

2008-01-01

270

Visualization of cardiac dynamics using physics-based deformable model  

NASA Astrophysics Data System (ADS)

Modeling of moving anatomic structures is complicated by the complexity of motion intrinsic and extrinsic to the structures. However when motion is cyclical, such as in heart, effective dynamic modeling can be approached using modern fast imaging techniques, which provide 3D structural data. Data may be acquired as a sequence of 3D volume images throughout the cardiac cycle. To model the intricate non- linear motion of the heart, we created a physics-based surface model which can realistically deform between successive time points in the cardiac cycle, yielding a dynamic 4D model of cardiac motion. Sequences of fifteen 3D volume images of intact canine beating hearts were acquired during compete cardiac cycles using the Dynamic Spatial Reconstructor and the Electron Beam CT. The chambers of the heart were segmented at successive time points, typically at 1/15-second intervals. The left ventricle of the first item point was reconstructed as an initial triangular mesh. A mass-spring physics-based deformable model, which can expand and shrink with local contraction and stretching forces distributed in an anatomically accurate simulation of cardiac motion, was applied to the initial mesh and allowed the initial mesh to deform to fit the left ventricle in successive time increments of the sequence. The resultant 4D model can be interactively transformed and displayed with associated regional electrical activity mapped onto the anatomic surfaces, producing a 5D mode, which faithfully exhibits regional cardiac contraction and relaxation patterns over the entire heart. For acquisition systems that may provide only limited 4D data, the model can provide interpolated anatomic shape between time points. This physics-based deformable model accurately represents dynamic cardiac structural changes throughout the cardiac cycle. Such models provides the framework for minimizing the number of time points required to usefully depict regional motion of myocardium and allowing quantitative assessment of regional myocardial dynamics. The electrical activation mapping provides spatial and temporal correlation within the cardiac cycle. In procedures such as intra-cardiac catheter ablation, visualization of the dynamic mole can be used to accurately localize the foci of myocardial arrhythmias and guide positioning of catheters for effective ablation.

Lin, Wei-te; Robb, Richard A.

2000-04-01

271

New design for an endo-esophageal probe intended for the ablation of cardiac muscle in the left-atrium: A parametric simulation study  

NASA Astrophysics Data System (ADS)

A parametric simulation study was carried out to establish optimal dimensions of endo-esophageal devices intended to treat the atrial fibrillation (AF). The devices are spherical-surface sections truncated at 15 mm (depth of 4 mm) and cut in concentric-rings each composed of independently driven sectors. The number of independent elements (N) was minimized for different values of ratio of amplitude of secondary lobe over main lobe (E) of 0.35, 0.4, 0.45 and 0.5 and for a volume of interest (VOI) of 24×27×28 mm3 (located at 23.5 mm from the center of the device), which is large enough to contain all the targets identified in the Visible Human Project Male specimen. Operating at 1 MHz, E and N were calculated in function of the element size and focal length (F). After keeping values of F and normalized dimensions of the independent elements in terms of wavelength, higher frequencies were considered: 1.25 and 1.5 MHz. Lesion formation in the heart chamber showed that the twelve configurations were able to produce the typical lesion used to treat the AF while preserving surrounding structures. For an exposure of 5 s and maximal temperature of 70 Â?C, the average (s.d.) acoustical intensity at transducer surface varied from 22.3(5.8)W/cm2 for a device with F = 98 mm at 1 MHz to 9.2(2.1)W/cm2 for a device with F = 186 mm at 1.5 MHz, while requiring 319 and 1158 elements, respectively, and achieving values of E of 0.5 and 0.41, respectively.

Pichardo, Samuel; Hynynen, Kullervo

2009-04-01

272

Separation of afterload reduction and a direct beneficial cardiac effect of nifedipine in congestive cardiomyopathy.  

PubMed

To assess whether the calcium antagonist nifedipine has a specific, direct effect on left ventricular diastolic function separate from its vasodilatory action, we studied 10 patients with idiopathic congestive cardiomyopathy (ages 28-69, New York Heart Association Class III or IV) at 30 min, 2 h, and 6 h after administration of 10 mg of sublingual nifedipine. Hemodynamic parameters were assessed with Swan-Ganz catheter and two-dimensional echo images were processed with computer-assisted analysis (Quantic 1200) to obtain left ventricular chamber areas and an index of rapid diastolic filling. Indices of left ventricular systolic performance (cardiac index and left ventricular area change fraction) improved during the early (30 min and 2 h) observation periods as afterload (estimated by systolic blood pressure and systemic vascular resistance) was reduced (p less than .05 vs. baseline). Pulmonary capillary wedge pressure fell from 17 mmHg to 11 mmHg and rapid diastolic filling index increased from .28 (% area change/ms) to .37 (% area change/ms) (p less than .05 vs. baseline) during the early observation periods. Indices of left ventricular systolic performance and afterload had returned to baseline at the late (6 h) observation period. However, pulmonary capillary wedge pressure remained reduced significantly at 10 mmHg after 6 h (p less than .05 vs. baseline). Preload (estimated by left ventricular end-diastolic chamber area) did not vary throughout the study period. Reduction of pulmonary capillary wedge pressure at 6 h, despite return of afterload reduction to baseline and no change in preload, suggests improved left ventricular chamber compliance after sublingual nifedipine, not related to alteration of left ventricular loading conditions. PMID:2766589

Percy, R F; Bass, T A; Conetta, D A; Miller, A B

1989-08-01

273

Automatic classification of scar tissue in late gadolinium enhancement cardiac MRI for the assessment of left-atrial wall injury after radiofrequency ablation  

NASA Astrophysics Data System (ADS)

Radiofrequency ablation is a promising procedure for treating atrial fibrillation (AF) that relies on accurate lesion delivery in the left atrial (LA) wall for success. Late Gadolinium Enhancement MRI (LGE MRI) at three months post-ablation has proven effective for noninvasive assessment of the location and extent of scar formation, which are important factors for predicting patient outcome and planning of redo ablation procedures. We have developed an algorithm for automatic classification in LGE MRI of scar tissue in the LA wall and have evaluated accuracy and consistency compared to manual scar classifications by expert observers. Our approach clusters voxels based on normalized intensity and was chosen through a systematic comparison of the performance of multivariate clustering on many combinations of image texture. Algorithm performance was determined by overlap with ground truth, using multiple overlap measures, and the accuracy of the estimation of the total amount of scar in the LA. Ground truth was determined using the STAPLE algorithm, which produces a probabilistic estimate of the true scar classification from multiple expert manual segmentations. Evaluation of the ground truth data set was based on both inter- and intra-observer agreement, with variation among expert classifiers indicating the difficulty of scar classification for a given a dataset. Our proposed automatic scar classification algorithm performs well for both scar localization and estimation of scar volume: for ground truth datasets considered easy, variability from the ground truth was low; for those considered difficult, variability from ground truth was on par with the variability across experts.

Perry, Daniel; Morris, Alan; Burgon, Nathan; McGann, Christopher; MacLeod, Robert; Cates, Joshua

2012-02-01

274

Left ventricular mass estimated by M-mode echocardiogram is not altered by changes in cardiac shape and dimensions due to acute arterial hypertension.  

PubMed

The effect of changes in left ventricular (LV) shape and dimensions due to acute arterial hypertension induced by mechanical obstruction of the aorta for 10 min on LV mass values estimated by M-mode echocardiogram was studied in 14 anesthetized dogs. Although the systolic pressure increased from 117.5 +/- 19.9 to 175.4 +/- 22.9 mmHg altered ventricular diameter from 2.77 +/- 0.49 cm to 3.17 +/- 0.67 cm (P < 0.05) and wall thickness from 0.83 +/- 0.09 to 0.75 +/- 0.09 cm (P < 0.05), LV mass estimated before (73.5 +/- 19.1 g) and after (78.3 +/- 26.4 g) hypertension was not significantly different. We demonstrate here for the first time that changes in LV dimensions induced by acute arterial hypertension do not modify LV mass values estimated by the M-mode electrocardiogram method. PMID:8257918

Matsubara, B B; Bregagnollo, E A; Tucci, P J

1993-02-01

275

Left-ventricular non-compaction with congenital left ventricular diverticulum.  

PubMed

Left-ventricular non-compaction may be isolated or associated with other cardiac or noncardiac anomalies. Left-ventricular non-compaction associated with left ventricular diverticulum is very rare. We describe a 30 year-old pregnant woman with a long standing diagnosis of biventricular non-compaction in whom a hidden left ventricular apical diverticulum was detected on transthoracic echocardiography. Both these conditions increase the risk of thromboembolism. Additionally, she was also diagnosed to have endocervical adenocarcinoma. This case suggests that a comprehensive echocardiographic examination is mandatory in cases of suspected isolated left-ventricular non-compaction to detect any other associated cardiac or noncardiac anomalies. PMID:21856225

Panduranga, Prashanth; Thomas, Eapen; Al-Mukhaini, Mohammed

2012-04-01

276

Nonobstructive Hypertrophic Cardiomyopathy with Left Ventricular Aneurysm  

PubMed Central

Hypertrophic cardiomyopathy with concomitant left ventricular aneurysm is rare and has important clinical implications, including an increased risk of sudden cardiac death. Most patients with this rare combination have obstructive hypertrophic cardiomyopathy, but we treated a 26-year-old woman who had nonobstructive hypertrophic cardiomyopathy and a family history of probable sudden cardiac death. In our patient, coronary angiograms showed distal occlusion of the left anterior descending coronary artery. Late gadolinium-enhanced cardiac magnetic resonance images showed scattered fibrosis within and beyond the left ventricular aneurysm. Precautionary therapy with an implantable cardioverter-defibrillator yielded an uneventful outcome. Cardiac magnetic resonance has emerged as a promising method for diagnosing these aneurysms and detecting associated myocardial fibrosis, thereby enabling patient risk stratification and the determination of appropriate therapeutic options. We discuss the role of cardiac magnetic resonance imaging in the management of this rare clinical entity.

Luni, Faraz Khan; Moza, Ankush; Sheikh, Mujeeb; Coker, Melinda F.; Chaganti, Srivasvi K.; Lewis, Terrence J.; Kanjwal, Yousuf

2013-01-01

277

Liquid Wall Chambers  

Microsoft Academic Search

The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions

2011-01-01

278

Stove with multiple chambers  

Microsoft Academic Search

A stove is described for burning a solid fuel such as wood. The wall means defines a main air inlet, a combustion gas outlet, and four chambers through which gas passes sequentially from the main air inlet to the combustion gas outlet. The chambers comprises a pre-heat plenum chamber into which the main air inlet opens. A main combustion chamber

1987-01-01

279

Anthropomorphic Cardiac Ultrasound Phantom.  

National Technical Information Service (NTIS)

Apparatus and method are disclosed for producing ultrasound readings of simulated blood flow through a model left ventricle or larger portion of the human heart, held inside a fluid filled chamber with membrane-covered windows, and through mitral and aort...

S. W. Smith J. E. Rinaldi

1988-01-01

280

Segmentation of the endocardial wall of the left atrium using local region-based active contours and statistical shape learning  

NASA Astrophysics Data System (ADS)

Atrial fibrillation, a cardiac arrhythmia characterized by unsynchronized electrical activity in the atrial chambers of the heart, is a rapidly growing problem in modern societies. One treatment, referred to as catheter ablation, targets specific parts of the left atrium for radio frequency ablation using an intracardiac catheter. Magnetic resonance imaging has been used for both pre- and and post-ablation assessment of the atrial wall. Magnetic resonance imaging can aid in selecting the right candidate for the ablation procedure and assessing post-ablation scar formations. Image processing techniques can be used for automatic segmentation of the atrial wall, which facilitates an accurate statistical assessment of the region. As a first step towards the general solution to the computer-assisted segmentation of the left atrial wall, in this paper we use shape learning and shape-based image segmentation to identify the endocardial wall of the left atrium in the delayed-enhancement magnetic resonance images.

Gao, Yi; Gholami, Behnood; MacLeod, Robert S.; Blauer, Joshua; Haddad, Wassim M.; Tannenbaum, Allen R.

2010-03-01

281

Cardiac Resynchronization Pacing Therapy  

Microsoft Academic Search

Approximately one third of patients with congestive heart failure and systolic dysfunction have an intraventricular conduction delay that is manifested as a QRS duration >120 ms. An intraventricular conduction delay adversely affects ventricular performance by causing dyssynchrony in ventricular activation. When ventricular dyssynchrony is present, simultaneous left and right ventricular pacing or cardiac resynchronization therapy can improve ventricular synchrony. This

Cash Casey; Bradley P. Knight

2004-01-01

282

Fluid-dynamics modelling of the human left ventricle with dynamic mesh for normal and myocardial infarction: preliminary study.  

PubMed

Pulsating blood flow patterns in the left ventricular (LV) were computed for three normal subjects and three patients after myocardial infarction (MI). Cardiac magnetic resonance (MR) images were obtained, segmented and transformed into 25 frames of LV for a computational fluid dynamics (CFD) study. Multi-block structure meshes were generated for 25 frames and 75 intermediate grids. The complete LV cycle was modelled by using ANSYS-CFX 12. The flow patterns and pressure drops in the LV chamber of this study provided some useful information on intra-LV flow patterns with heart diseases. PMID:22795507

Khalafvand, S S; Ng, E Y K; Zhong, L; Hung, T K

2012-07-12

283

Titin isoform switching is a major cardiac adaptive response in hibernating grizzly bears  

PubMed Central

The hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. Here we studied how hibernating grizzly bears (Ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. We evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and hibernating period. Because both collagen and titin are involved in altering diastolic function, we investigated both in the myocardium of active and hibernating grizzly bears. Heart rates were reduced from 84 beats/min in active bears to 19 beats/min in hibernating bears. Diastolic volume, stroke volume, and left ventricular ejection fraction were not different. However, left ventricular muscle mass was significantly lower (300 ± 12 compared with 402 ± 14 g; P = 0.003) in the hibernating bears, and as a result the diastolic volume-to-left ventricular muscle mass ratio was significantly greater. Early ventricular filling deceleration times (106.4 ± 14 compared with 143.2 ± 20 ms; P = 0.002) were shorter during hibernation, suggesting increased ventricular stiffness. Restrictive pulmonary venous flow patterns supported this conclusion. Collagen type I and III comparisons did not reveal differences between the two groups of bears. In contrast, the expression of titin was altered by a significant upregulation of the stiffer N2B isoform at the expense of the more compliant N2BA isoform. The mean ratio of N2BA to N2B titin was 0.73 ± 0.07 in the active bears and decreased to 0.42 ± 0.03 (P = 0.006) in the hibernating bears. The upregulation of stiff N2B cardiac titin is a likely explanation for the increased ventricular stiffness that was revealed by echocardiography, and we propose that it plays a role in preventing chamber dilation in hibernating grizzly bears. Thus our work identified changes in the alternative splicing of cardiac titin as a major adaptive response in hibernating grizzly bears.

Nelson, O. Lynne; Robbins, Charles T.; Wu, Yiming; Granzier, Henk

2008-01-01

284

Titin isoform switching is a major cardiac adaptive response in hibernating grizzly bears.  

PubMed

The hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. Here we studied how hibernating grizzly bears (Ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. We evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and hibernating period. Because both collagen and titin are involved in altering diastolic function, we investigated both in the myocardium of active and hibernating grizzly bears. Heart rates were reduced from 84 beats/min in active bears to 19 beats/min in hibernating bears. Diastolic volume, stroke volume, and left ventricular ejection fraction were not different. However, left ventricular muscle mass was significantly lower (300 +/- 12 compared with 402 +/- 14 g; P = 0.003) in the hibernating bears, and as a result the diastolic volume-to-left ventricular muscle mass ratio was significantly greater. Early ventricular filling deceleration times (106.4 +/- 14 compared with 143.2 +/- 20 ms; P = 0.002) were shorter during hibernation, suggesting increased ventricular stiffness. Restrictive pulmonary venous flow patterns supported this conclusion. Collagen type I and III comparisons did not reveal differences between the two groups of bears. In contrast, the expression of titin was altered by a significant upregulation of the stiffer N2B isoform at the expense of the more compliant N2BA isoform. The mean ratio of N2BA to N2B titin was 0.73 +/- 0.07 in the active bears and decreased to 0.42 +/- 0.03 (P = 0.006) in the hibernating bears. The upregulation of stiff N2B cardiac titin is a likely explanation for the increased ventricular stiffness that was revealed by echocardiography, and we propose that it plays a role in preventing chamber dilation in hibernating grizzly bears. Thus our work identified changes in the alternative splicing of cardiac titin as a major adaptive response in hibernating grizzly bears. PMID:18502907

Nelson, O Lynne; Robbins, Charles T; Wu, Yiming; Granzier, Henk

2008-05-23

285

Left ventricular wall stress compendium.  

PubMed

Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models. PMID:21547783

Zhong, L; Ghista, D N; Tan, R S

2011-06-21

286

Cardiac Magnetic Resonance Imaging Findings in 20-year Survivors of Mediastinal Radiotherapy for Hodgkin's Disease  

SciTech Connect

Purpose: The recognition of the true prevalence of cardiac toxicity after mediastinal radiotherapy requires very long follow-up and a precise diagnostic procedure. Cardiac magnetic resonance imaging (MRI) permits excellent quantification of cardiac function and identification of localized myocardial defects and has now been applied to a group of 20-year Hodgkin's disease survivors. Methods and materials: Of 143 patients treated with anterior mediastinal radiotherapy (cobalt-60, median prescribed dose 40 Gy) for Hodgkin's disease between 1978 and 1985, all 53 survivors were invited for cardiac MRI. Of those, 36 patients (68%) presented for MRI, and in 31 patients (58%) MRI could be performed 20-28 years (median, 24) after radiotherapy. The following sequences were acquired on a 1.5-T MRI: transversal T1-weighted TSE and T2-weighted half-fourier acquisition single-shot turbo-spin-echo sequences, a steady-state free precession (SSFP) cine sequence in the short heart axis and in the four-chamber view, SSFP perfusion sequences under rest and adenosine stress, and a SSFP inversion recovery sequence for late enhancement. The MRI findings were correlated with previously reconstructed doses to cardiac structures. Results: Clinical characteristics and reconstructed doses were not significantly different between survivors undergoing and not undergoing MRI. Pathologic findings were reduced left ventricular function (ejection fraction <55%) in 7 (23%) patients, hemodynamically relevant valvular dysfunction in 13 (42%), late myocardial enhancement in 9 (29%), and any perfusion deficit in 21 (68%). An association of regional pathologic changes and reconstructed dose to cardiac structures could not be established. Conclusions: In 20-year survivors of Hodgkin's disease, cardiac MRI detects pathologic findings in approximately 70% of patients. Cardiac MRI has a potential role in cardiac imaging of Hodgkin's disease patients after mediastinal radiotherapy.

Machann, Wolfram; Beer, Meinrad [Department of Radiology, University of Wuerzburg (Germany); Breunig, Margret; Stoerk, Stefan; Angermann, Christiane [Department of Cardiology, University of Wuerzburg (Germany); Seufert, Ines; Schwab, Franz; Koelbl, Oliver; Flentje, Michael [Department of Radiation Oncology, University of Wuerzburg (Germany); Vordermark, Dirk, E-mail: dirk.vordermark@medizin.uni-halle.d [Department of Radiation Oncology, University of Wuerzburg (Germany); Department of Radiation Oncology, Martin Luther University Halle-Wittenberg (Germany)

2011-03-15

287

Primary Cardiac Angiofibroma  

PubMed Central

Cardiac Angiofibroma is an uncommon intracardiac tumor. Thus far, only 4 cases of the rare intracardiac tumor have been reported. The present case-report describes an intracardiac angiofibroma in a 57-year-old healthy female. The patient was incidentally diagnosed with a left ventricle mass during echocardiography. We performed cardiac imaging, surgical excision and histological evaluation of the mass. The angiofibroma demonstrated features different from the relatively common cardiac tumors such as fibroma, myxoma and angiosarcoma. The cardiac MRI showed slightly high signal intensity on both T1 and T2, with the central core of lower signal intensity. The resected tumor was a whitish and rubbery mass. Histologically, the tumor showed the benign vascular proliferations associated with the surrounding collagen deposition.

Kim, Young Ju; Kim, Young Jin; Kim, Se Hoon; Youn, Young-Nam

2013-01-01

288

8. SEDIMENTATION CHAMBER, VIEW UPSTREAM (PLANK COVER REMOVED FOR CLARITY). ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. SEDIMENTATION CHAMBER, VIEW UPSTREAM (PLANK COVER REMOVED FOR CLARITY). BOX FLUME DROPS SLIGHTLY INTO CHAMBER ON LEFT SIDE. CHAMBER IS A SERIES OF BAFFLES DESIGNED TO SLOW THE FLOW OF WATER. FLOW IS REDUCED TO ALLOW PARTICULATES TO SETTLE TO THE BOTTOM. TWO SCREENS (NOT SHOWN) FILTER LARGER DEBRIS. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

289

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 19371938, VIEWED FROM DOWNSTREAM. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 1937-1938, VIEWED FROM DOWNSTREAM. DEBRIS REMOVED FROM TOP PLANKS FOR CLARITY. ONE OF TWO SPILLWAYS SEEN AT RIGHT. FLUSH VALVE SEEN AT LOWER LEFT AND WRENCH FOR VALVES IS PROPPED AGAINST CHAMBER. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

290

Combustion chamber construction  

Microsoft Academic Search

A combustion chamber is described for use in gas turbine engines, the chamber comprising: an inlet for receiving air and fuel to be burned; an outlet for expelling products of combustion; high strength structural frame means disposed between the inlet and the outlet for supporting mechanical forces associated with the chamber; liner means cooperating with the frame and defining a

A. P. Sterman; T. G. Wakeman; J. J. Williams

1986-01-01

291

Hearts of Dystonia musculorum Mice Display Normal Morphological and Histological Features but Show Signs of Cardiac Stress  

PubMed Central

Dystonin is a giant cytoskeletal protein belonging to the plakin protein family and is believed to crosslink the major filament systems in contractile cells. Previous work has demonstrated skeletal muscle defects in dystonin-deficient dystonia musculorum (dt) mice. In this study, we show that the dystonin muscle isoform is localized at the Z-disc, the H zone, the sarcolemma and intercalated discs in cardiac tissue. Based on this localization pattern, we tested whether dystonin-deficiency leads to structural defects in cardiac muscle. Desmin intermediate filament, microfilament, and microtubule subcellular organization appeared normal in dt hearts. Nevertheless, increased transcript levels of atrial natriuretic factor (ANF, 66%) ?-myosin heavy chain (beta-MHC, 95%) and decreased levels of sarcoplasmic reticulum calcium pump isoform 2A (SERCA2a, 26%), all signs of cardiac muscle stress, were noted in dt hearts. Hearts from two-week old dt mice were assessed for the presence of morphological and histological alterations. Heart to body weight ratios as well as left ventricular wall thickness and left chamber volume measurements were similar between dt and wild-type control mice. Hearts from dt mice also displayed no signs of fibrosis or calcification. Taken together, our data provide new insights into the intricate structure of the sarcomere by situating dystonin in cardiac muscle fibers and suggest that dystonin does not significantly influence the structural organization of cardiac muscle fibers during early postnatal development.

Kothary, Rashmi; Boudreau-Lariviere, Celine

2010-01-01

292

Stove with multiple chambers  

SciTech Connect

A stove is described for burning a solid fuel such as wood. The wall means defines a main air inlet, a combustion gas outlet, and four chambers through which gas passes sequentially from the main air inlet to the combustion gas outlet. The chambers comprises a pre-heat plenum chamber into which the main air inlet opens. A main combustion chamber contains solid fuel to be burned into which gas passes from the pre-heat plenum chamber, a second combustion chamber which is downstream of the main combustion chamber with respect to the flow of gas from the main air inlet to the combustion gas outlet, and a third combustion chamber from which the combustion gas outlet opens. The stove also comprises a plate having a restricted opening for providing communication between the second and third combustion chambers. And a catalytic converter comprises a body of solid material formed with passageways, the body of solid material being fitted in the restricted opening so that gas passes from the second combustion chamber to the third combustion chamber by way of the passageways in the body.

Black, A.

1987-04-21

293

Visualization of the cardiac venous system using cardiac magnetic resonance.  

PubMed

We sought to investigate the value of cardiac magnetic resonance to depict cardiac venous anatomy. For cardiac resynchronization therapy the lead for the left ventricle is usually placed by transvenous approach into a tributary of the coronary sinus (CS). Knowledge of the anatomy and variations of the cardiac venous system may facilitate the positioning of the left ventricle lead. The cardiac magnetic resonance examinations of 23 subjects (16 volunteers and 7 patients) were retrospectively analyzed. All examinations were performed using navigator-gated whole-heart steady-state free precession coronary artery imaging after administration of intravascular contrast agents (gadofosveset in volunteers; Gadomer-17 in patients). The cardiac venous system was visualized in all subjects. The most frequent anatomical variant observed (in 12 subjects [52%]) was a connection of the small cardiac vein to the CS at the crux cordis. In 10 subjects (44%) the small veins entered the right atrium independently from the CS, and the posterior interventricular vein was connected to the CS at the crux cordis. Only one subject had a disconnection between the CS and posterior interventricular vein, which entered into the right atrium independently. The mean distance of the posterior vein of the left ventricle and the left marginal vein to the ostium of the CS was 15.2+/-4.7 mm and 49.7+/-14.1 mm, respectively. In conclusion, the anatomy of the cardiac venous system and its anatomical variability can be described using cardiac magnetic resonance. Its preimplantation visualization may help to facilitate the implant procedure and to reduce fluoroscopy time. PMID:18237610

Chiribiri, Amedeo; Kelle, Sebastian; Götze, Stephan; Kriatselis, Charalampos; Thouet, Thomas; Tangcharoen, Tarinee; Paetsch, Ingo; Schnackenburg, Bernhard; Fleck, Eckart; Nagel, Eike

2007-12-21

294

Cardiac metabolism and arrhythmias  

PubMed Central

Sudden cardiac death remains a leading cause of mortality in the Western world, accounting for up to 20% of all deaths in the U.S.1, 2 The major causes of sudden cardiac death in adults age 35 and older are coronary artery disease (70–80%) and dilated cardiomyopathy (10–15%).3 At the molecular level, a wide variety of mechanisms contribute to arrhythmias that cause sudden cardiac death, ranging from genetic predisposition (rare mutations and common polymorphisms in ion channels and structural proteins) to acquired electrophysiological and structural remodeling in left ventricular hypertrophy and failure.4, 5 A growing body of evidence suggests that altered ion channel function is closely linked to changes in metabolic activity in a wide variety of pathological conditions. In this review we focus on the mechanisms by which altered metabolic function impacts cardiac electrophysiology. We will review the specific molecular targets that allow cardiomyocytes to recognize alterations in their metabolic state and translate this information into changes in membrane excitability in various pathophysiological conditions including ischemia-reperfusion, heart failure (HF), left ventricular hypertrophy, diabetic cardiomyopathy and atrial fibrillation. A comprehensive understanding of the interrelated processes of metabolic and electrical remodeling promises to identify new molecular targets for the treatment of cardiac arrhythmias.

Barth, Andreas S; Tomaselli, Gordon F

2009-01-01

295

Significance of QRS morphology in determining the prevalence of mechanical dyssynchrony in heart failure patients eligible for cardiac resynchronization: particular focus on patients with right bundle branch block with and without coexistent left-sided conduction defects  

Microsoft Academic Search

Aims The aim of this study was to assess the significance of QRS morphology in determining the preva- lence of mechanical dyssynchrony in heart failure (HF) patients considered eligible for cardiac resyn- chronization. Methods and results A total of 200 consecutive HF patients (158 males, mean age 56 + 13.5 years) with standard indications for cardiac resynchronization therapy (CRT) were

Majid Haghjoo; Ataallah Bagherzadeh; Maryam Moshkani Farahani; Zahra Ojaghi Haghighi; Mohammad Ali Sadr-Ameli

296

Auxiliary combustion chamber  

SciTech Connect

An auxiliary combustion chamber is described for an internal combustion engine, the chamber comprises: (a) a chamber liner formed of a ceramic material that is an effective thermal insulator, the chamber liner having substantially hemispherical internal and external surfaces; (b) an outer metal member cast around the chamber liner, the outer member including a substantially hemispherical portion contacting the outer surface of the chamber liner and imparting a compressive stress to the chamber liner; the metal member further includes a substantially cylindrical portion contiguous with the open end of the hemispherical portion and extending beyond the chamber liner; the cylindrical portion has an inner surface of a predetermined inside diameter at ambient temperature; and (c) a substantially cup-shaped nozzle portion formed of a heat-resistant ceramic material and having an orifice disposed in the bottom to provide flow communication from a main combustion chamber to the interior of the auxiliary combustion chamber, the nozzle portion includes a substantially cylindrical outer surface having a diameter greater than predetermined inside diameter of cylindrical portion of the metal member; the nozzle portion is shrink-fit within the cylindrical portion of the outer metal member with the cylindrical outer surface of the ceramic nozzle contacting the inner surface of the cylindrical portion of the metal member. The bottom of the nozzle portion is disposed away from the hemispherical portion of the metal member.

Kawamura, M.; Taniguchi, M.

1987-06-30

297

Flow in left atrium using MR fluid motion estimation  

NASA Astrophysics Data System (ADS)

A recent development based on optical flow applied onto Fast Imaging in Steady State Free Precession (TrueFISP) magnetic resonance imaging is able to deliver good estimation of the flow profile in the human heart chamber. The examination of cardiac flow based on tracking of MR signals emitted by moving blood is able to give medical doctors insight into the flow patterns within the human heart using standard MRI procedure without specifically subjecting the patient to longer scan times using more dedicated scan protocols such as phase contrast MRI. Although MR fluid motion estimation has its limitations in terms of accurate flow mapping, the use of a comparatively quick scan procedure and computational post-processing gives satisfactory flow quantification and can assist in management of cardiac patients. In this study, we present flow in the left atria of five human subjects using MR fluid motion tracking. The measured flow shows that vortices exist within the atrium of heart. Although the scan is two-dimensional, we have produced multiple slices of flow maps in a spatial direction to show that the vortex exist in a three-dimensional space.

Wong, Kelvin K. L.; Kelso, Richard M.; Worthley, Steve M.; Sanders, Prash; Mazumdar, Jagannath; Abbott, Derek

2007-12-01

298

Cardiac hypertrophy in surgically denervated dogs with aortic stenosis  

Microsoft Academic Search

Summary Left ventricular cell hypertrophy in dogs with aortic stenosis was accelerated by surgical denervation of the left ventricle. We conclude that there are neural mechanisms which, when present, inhibit cardiac cell hypertrophy.

T. Matoba; K. Adachi; T. Ito; Y. Yamashita; M. Chiba; K. Odawara; S. Inuzuka; H. Toshima

1984-01-01

299

Left Atrial Thrombus  

PubMed Central

Rationale:Echocardiography is essential in establishing the diagnosis in patients with cardiac masses. The differentiation between myxomas and thrombi is sometimes difficult, but is critical in making the right therapeutical decision. Objective: A 70–year–old female presented to the Emergency Department with palpitations, dyspnea and anterior epistaxis. She had a 3 years history of atrial fibrillation and chronic heart failure NYHA class III. Method and Result: Two-dimensional transthoracic echocardiography showed the thickening of the mitral valves with moderate mitral insufficiency and a mobile round mass in the left atrium, heterogeneous, inhomogeneous, 18 mm in size, attached with a narrow stalk to the interatrial septum, reaching mitral annular plane; tricuspid insufficiency with a maximum 30 mmHg gradient, intact interatrial septum, akinesia of two thirds of basal inferior wall, 42% ejection fraction. Discussion: The two–dimensional transesophageal echocardiography confirmed the intraatrial mass. Epistaxis was considered to be due to heart failure and the increased venous pressure. The patient was referred to the cardiovascular surgery clinic, but refused surgery. Anticoagulation with fraxiparine 0,6 ml/day was started and continued for 3 weeks, after cessation of epistaxis by nasal tamponament. Then echocardiography was repeated, with no remnant mass in the left atrium. The conclusion was that the mass must have been a thrombus that has melted away. In this particular case, the left intraatrial thrombus may have been due to the presence of atrial fibrillation.

2011-01-01

300

Cardiac perforation from implantable cardioverter-defibrillator lead placement: insights from the national cardiovascular data registry.  

PubMed

Background- Cardiac perforation is a feared complication of implantable cardioverter-defibrillator (ICD) lead implantation because of the potential for significant morbidity and mortality. Predictors of perforation and the severity of associated adverse events have not been well studied. We sought to identify predictors of cardiac perforation from ICD lead implantation and subsequent outcomes. Methods and Results- We studied 440?251 first-time ICD recipients in the ICD Registry implanted between January 2006 and September 2011. Using hierarchical multivariable logistic regression adjusting for patient, implanting physician, and hospital characteristics, we examined the predictors of perforation and the association of perforation with other major complications, length of stay, and in-hospital mortality. Cardiac perforation occurred in 625 patients (0.14%). After multivariable adjustment, older age, female sex, left bundle branch block, worsened heart failure class, higher left ventricular ejection fraction, and non-single-chamber ICD implant were associated with a greater odds of perforation. Conversely, atrial fibrillation, diabetes mellitus, previous cardiac bypass surgery, and higher implanter procedural volume were associated with a lower odds of perforation (all P<0.05). After adjustment, ICD recipients with perforation had greater odds of other associated major complications (odds ratio, 27.5; 95% confidence interval, 19.9-38.0; P<0.0001), postprocedural hospital stays >3 days (odds ratio, 16.3; 95% confidence interval, 13.7-19.4; P<0.0001), and in-hospital death (odds ratio, 17.7; 95% confidence interval, 12.2-25.6; P<0.0001). Conclusions- In a large population of ICD recipients, specific patient and implanter characteristics predicted cardiac perforation risk. Cardiac perforation was associated with a substantially increased risk of other major complications, prolonged hospital stays, and death. PMID:24002030

Hsu, Jonathan C; Varosy, Paul D; Bao, Haikun; Dewland, Thomas A; Curtis, Jeptha P; Marcus, Gregory M

2013-09-03

301

Fetal cardiac hypertrophy and cardiac function in diabetic pregnancies  

Microsoft Academic Search

OBJECTIVE: Our purpose was to evaluate the relationship between fetal cardiac wall hypertrophy and ventricular function in fetuses of metabolically controlled, insulin-requiring diabetics.STUDY DESIGN: M-mode directed fetal echocardiography included measurements of left and right ventricular free wall and interventricular septal thickness and ventricular diastolic and systolic dimensions. Fetal measurements included biparietal diameter, estimation of fetal weight, and cardiac area\\/thoracic area.

Jyotsna A. Gandhi; Xiao Yang Zhang; Jack E. Maidman

1995-01-01

302

Cardiac abnormalities in young women with anorexia nervosa.  

PubMed Central

OBJECTIVE--To identify the characteristics of cardiac involvement in the self-induced starvation phase of anorexia nervosa. METHODS--Doppler echocardiographic indices of left ventricular geometry, function, and filling were examined in 21 white women (mean (SD) 22 (5) years) with anorexia nervosa according to the DSMIII (Diagnostic and Statistical Manual of Mental Disorders) criteria, 19 women (23 (2) years) of normal weight, and 22 constitutionally thin women (21 (4) years) with body mass index < 20. RESULTS--13 patients (62%) had abnormalities of mitral valve motion compared with one normal weight woman and two thin women (p < 0.001) v both control groups). Left ventricular chamber dimension and mass were significantly less in women with anorexia nervosa than in either the women of normal weight or the thin women, even after standardisation for body size or after controlling for blood pressure. There were no substantial changes in left ventricular shape. Midwall shortening as a percentage of the values predicted from end systolic stress was significantly lower in the starving patients than in women of normal weight: when endocardial shortening was used as the index this difference was overestimated. The cardiac index was also significantly reduced in anorexia nervosa because of a low stroke index and heart rate. The total peripheral resistance was significantly higher in starving patients than in both control groups. The left atrial dimension was significantly smaller in anorexia than in the women of normal weight and the thin women, independently of body size. The transmitral flow velocity E/A ratio was significantly higher in anorexia than in both the control groups because of the reduction of peak velocity A. When data from all three groups were pooled the flow velocity E/A ratio was inversely related to left atrial dimension (r = -0.43, p < 0.0001) and cardiac output (r = -0.64, p < 0.0001) independently of body size. CONCLUSIONS--Anorexia nervosa caused demonstrable abnormalities of mitral valve motion and reduced left ventricular mass and filling associated with systolic dysfunction.

de Simone, G.; Scalfi, L.; Galderisi, M.; Celentano, A.; Di Biase, G.; Tammaro, P.; Garofalo, M.; Mureddu, G. F.; de Divitiis, O.; Contaldo, F.

1994-01-01

303

Pseudoaneurysm of the left ventricle.  

PubMed Central

Pseudoaneurysm of the left ventricle most often occurs after transmural myocardial infarction but may also follow cardiac operations, trauma, inflammation, or infection. In contrast to patients with true ventricular aneurysm, those with false aneurysm most commonly die of hemorrhage. Review of the reported surgical experience and of our 14 cases confirms that standard chest radiographs with an abnormal cardiac silhouette and rapidly expanding size may alert the physician to this sometimes overlooked diagnosis. Noninvasive tests such as color-flow Doppler echocardiography, 2-dimensional echocardiography, cineangiographic computed tomography, and transesophageal echocardiography allow relatively easy recognition of these apparently rare lesions with increasing frequency. Cardiac catheterization, however, is usually still necessary for a clear picture of the location and anatomy of the aneurysm and the state of the coronary arteries. Finally, a new classification is proposed, consisting of true aneurysm, false aneurysm, pseudo-false aneurysm, and mixed aneurysm. Images

Mackenzie, J W; Lemole, G M

1994-01-01

304

Cardiac Transplantation in Friedreich Ataxia  

PubMed Central

In this paper, we describe a 14-year-old boy with a confirmed diagnosis of Friedreich ataxia who underwent cardiac transplantation for left ventricular failure secondary to dilated cardiomyopathy with restrictive physiology. His neurological status prior to transplantation reflected early signs of neurologic disease, with evidence of dysarthria, weakness, mild gait impairment, and limb ataxia. We review the ethical issues considered during the process leading to the decision to offer cardiac transplantation.

Yoon, Grace; Soman, Teesta; Wilson, Judith; George, Kristen; Mital, Seema; Dipchand, Anne I.; McCabe, Jane; Logan, William; Kantor, Paul

2013-01-01

305

Using a human cardiovascular-respiratory model to characterize cardiac tamponade and pulsus paradoxus  

Microsoft Academic Search

BACKGROUND: Cardiac tamponade is a condition whereby fluid accumulation in the pericardial sac surrounding the heart causes elevation and equilibration of pericardial and cardiac chamber pressures, reduced cardiac output, changes in hemodynamics, partial chamber collapse, pulsus paradoxus, and arterio-venous acid-base disparity. Our large-scale model of the human cardiovascular-respiratory system (H-CRS) is employed to study mechanisms underlying cardiac tamponade and pulsus

Deepa Ramachandran; Chuan Luo; Tony S Ma; John W Clark Jr

2009-01-01

306

Cardiac myxosarcoma with thoracic spinal metastasis.  

PubMed

Echocardiography revealed a left atrial tumor in a 59-year-old man with back pain that concurrently worsened with left foot drop and loss of the left ankle reflex soon after admission to our hospital. Magnetic resonance imaging of the spine revealed an epidural tumor extending from Th5 with spinal cord compression. The patient was immediately treated by emergency Th4-5 laminectomy and epidural decompression. One month later, a cardiac tumor excised via the left atrial approach was histopathologically diagnosed as myxosarcoma, and the Th5 tumor was consistent with this finding. This is the first report to describe spinal metastasis of cardiac myxosarcoma. PMID:23677508

Kimura, Mitsuhiro; Kikuchi, Chizuo; Takahashi, Yoshiki; Kanazawa, Hiroshi; Nakazawa, Satoshi

2013-05-16

307

The Mars Chamber  

NASA Video Gallery

The Mars chamber is a box about the size of a refrigerator that re-creates the temperatures, pressures, and atmosphere of the Martian surface, essentially creating a Mars environment on Earth! Scientists and engineers use this chamber to test experiments on the Sample Analysis at Mars (SAM) instrument suite--a fully-functioning chemistry lab aboard the Curiosity Mars rover.

gsfcvideo

2012-07-17

308

Combustion chamber noise suppressor  

Microsoft Academic Search

A combustion chamber is described for a hot fog generating machine comprising a hollow cylindrical combustion chamber shell having a closure plate at one end and outlet means at the opposite end for directing hot combustion gasses to a fogging nozzle, air inlet means disposed adjacent the outlet means, fuel inlet means and ignition means mounted in the closure plate

1986-01-01

309

Cardiac amyloidosis  

MedlinePLUS

... Primary cardiac amyloidosis - AL type; Secondary cardiac amyloidosis - AA type; Stiff heart syndrome; Senile amyloidosis ... arrhythmias and conduction disturbances (heart block). Secondary amyloidosis (AA type) rarely affects the heart. However, a form ...

310

Expanding cardiac resynchronization for systolic heart failure to patients with mechanical dyssynchrony and atrial fibrillation.  

PubMed

Despite progress in the management of heart failure (HF) using pharmacotherapy, the mortality and morbidity associated with this condition remain unacceptably high. Cardiac resynchronization therapy (CRT), a left-sided pacing therapy for drug-refractory and highly symptomatic HF patients with ventricular conduction delay, has been shown to improve left ventricular (LV) systolic function, myocardial oxygen consumption, and New York Heart Association functional class and to inhibit or reverse LV chamber dilation and remodeling. Atrial fibrillation is common in patients with HF and is associated with significant worsening of HF and myocardial function. Only recently have trials been designed to specifically study CRT in patients with HF and chronic atrial fibrillation. These studies have shown that CRT with biventricular or univentricular LV pacing in patients with atrial fibrillation corrects mechanical dyssynchrony and results in significant and sustained improvement in functional capacity, LV ejection fraction, quality of life, and QRS duration. PMID:16195687

Ghanbari, Hamid; Hassunizadeh, Bischan; Machado, Christian

2005-01-01

311

Swirl chamber type combustion chamber for diesel engine  

Microsoft Academic Search

This patent describes a swirl chamber type combustion chamber for a Diesel engine comprising: a piston head in the chamber defining a concavity which guides the stream of combustion gas injected from the swirl chamber into the main combustion chamber at the top dead center of the piston stroke, the concavity being formed in a substantially triangular configuration with an

K. Hataura; M. Nagahama

1989-01-01

312

The hemodynamics of cardiac tamponade.  

PubMed

The changes produced by acute pericardial tamponade were examined. Tamponade produced the expected hemodynamic alteration; namely, depression on cardiac output, left ventricular pressure and LV dp/dt and elevation of right atrial and intrapericardial pressures. The mechanism of the hemodynamic disturbances was that the elevation of the intrapericardial pressure produced a negative atrial transmural pressure and disturbed atrial and ventricle filling producing the vicious cycle: diminished venoatrial gradient leads to decreased cardiac output leads to attenuated effect of ventricular systole on atrial filling, and so forth. The myocardial contractility was not impaired in cardiac tamponade. PMID:642185

Nakata, Y; Takahashi, F

1978-02-01

313

Left-ventricular cavity automated-border detection using an autocovariance technique in echocardiography  

NASA Astrophysics Data System (ADS)

Left-ventricular (LV) segmentation is essential in the early detection of heart disease, where left-ventricular wall motion is being tracked in order to detect ischemia. In this paper, a new method for automated segmentation of the left-ventricular chamber is described. An autocorrelation-based technique isolates the LV cavity from the myocardial wall on 2-D slices of 3D short-axis echocardiograms. A morphological closing function and median filtering are used to generate a uniform border. The proposed segmentation technique is designed to be used in identifying the endocardial border and estimating the motion of the endocardial wall over a cardiac cycle. To this purpose, the proposed technique is particularly successful in border delineation by tracing around structures like papillary muscles and the mitral valve, which constitute the typical obstacle in LV segmentation techniques. The results using this new technique are compared to the manual detection results in short-axis views obtained at the papillary muscle level from 3D datasets in human and canine experiments in vivo. Qualitatively, the automatically-detected borders are highly comparable to the manually-detected borders enclosing regions in the left-ventricular cavity with a relative error within the range of 4.2% - 6%. The new technique constitutes, thus, a robust segmentation method for automated segmentation of endocardial borders and suitable for wall motion tracking for automated detection of ischemia.

Morda, Louis S.; Konofagou, Elisa E.

2005-04-01

314

Left ventricular endocardial ecchinococcosis associated with multiple intracranial hydatid cysts.  

PubMed

Cardiac ecchinococcosis is a rare disease. Its incidence varies from 0.02-2%. Commonly seen in the left ventricle arising from the myocardium in the subepicardial region.We report a 15-year-old boy presented with a rare combination of a left ventricular subendocardial hydatid cyst associated with multiple cysts in the left cerebral hemisphere and right posterior occipital lobe. The patient underwent successful surgical excision of the left ventricular hydatid cyst using cardiopulmonary bypass. PMID:23601473

Darwazah, Ahmad K; Zaghari, Mahmoud; Eida, Mohammed; Batrawy, Mohammed

2013-04-20

315

Old Riverdale Cotton Mill office building on left. The old ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Old Riverdale Cotton Mill office building on left. The old office building has also been used as a starch mixing house. Note entrance to new office building on right - Riverdale Cotton Mill, Office Building, Old, Valley, Chambers County, AL

316

Left ventricular volume determination using Albunex  

Microsoft Academic Search

The aim of this study was to assess the ability of intravenous injection of Albunex to improve left ventricular volume determination in patients with various cardiac diseases. It is conceivable that the intravenous injection of microbubbles could improve echocardiographic left ventricular border delineation leading to improved interobserver variability. Echocardiograms were obtained during simultaneous intravenous injection of 0.08 and 0.12 ml\\/kg

Rainer J. Zotz; Sabine Genth; Anne Waaler; Raimund Erbel; Jürgen Meyer

1996-01-01

317

Single ventricle cardiac defect.  

PubMed

Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. PMID:20527615

Eren, Bulent; Turkmen, Nursel; Turkmen, Nurset; Fedakar, Recep; Senel, Berna; Cetin, Volkan; Cetin, Volkn

2010-05-01

318

Atrial Thrombosis in Cardiac Amyloidosis: Diagnostic Contribution of Transesophageal Echocardiography  

Microsoft Academic Search

Few cases of atrial thrombosis detected by transesophageal echocardiography (TEE) in cardiac amyloidosis have been reported recently. We present the cases of 3 consecutive patients affected by AL-type cardiac amyloidosis, symptomatic for heart failure and in sinus rhythm. All patients had a cardiac restrictive pattern at Doppler examination. TEE showed left atrial thrombus in 2 patients and biatrial thrombi in

Mauro Santarone; Giovanni Corrado; Luca Mario Tagliagambe; Giovanni Foglia Manzillo; Giorgio Tadeo; Manuela Spata; Matteo Longhi

1999-01-01

319

Multiwire Proportional Chamber Development.  

National Technical Information Service (NTIS)

The development of large area multiwire proportional chambers, to be used as high resolution spatial detectors in cosmic ray experiments is described. A readout system was developed which uses a directly coupled, lumped element delay-line whose characteri...

R. F. Doolittle U. Pollvogt A. J. Eskovitz

1973-01-01

320

Entire left atrial myxoma presenting as a saddle embolus  

Microsoft Academic Search

A case is presented in which a complete left atrial myxoma became detached and lodged in the aortic bifurcation. Shortly after it had been removed the patient suffered cardiac arrest and could not be revived.

M. Kulkarni; I. Mc D. Jessiman

1969-01-01

321

Raloxifene Prevents Cardiac Hypertrophy and Dysfunction in Pressure-Overloaded Mice  

Microsoft Academic Search

Estradiol reduces myocardial hypertrophy and left ventricular mass, suggesting that the selective estrogen receptor modulator raloxifene may have similar effects. However, it is not clear whether raloxifene inhibits both cardiac hypertrophy and dysfunction. We used transverse aortic-banded mice to produce pressure-overload cardiac hypertrophy and used neonatal rat ventricular cardiomyocytes to investigate the cellular mechanisms of raloxifene on cardiac hypertrophy. Left

Hisakazu Ogita; Koichi Node; Yulin Liao; Fuminobu Ishikura; Shintaro Beppu; Hiroshi Asanuma; Shoji Sanada; Seiji Takashima; Tetsuo Minamino; Masatsugu Hori; Masafumi Kitakaze

2009-01-01

322

Sleeve reaction chamber system  

DOEpatents

A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

2009-08-25

323

Cardiac resynchronization: a novel therapy for heart failure.  

PubMed

Despite advances in medical therapy for patients with congestive heart failure, morbidity and mortality remain high. Conduction abnormalities, such as left bundle branch block, right bundle branch block, and nonspecific conduction delay, are observed commonly in patients with dilated cardiomyopathy. In patients with heart failure, the presence of intraventricular conduction delay is associated with more severe mitral regurgitation and worsened left ventricular systolic and diastolic function, and is an independent risk factor for increased mortality. Conventional dual-chamber (right atrial and right ventricular) pacing with a short atrioventricular delay was initially introduced as therapy for patients with advanced congestive heart failure to improve diastolic dysfunction and reduce mitral regurgitation. The acute beneficial hemodynamic effects observed in early, uncontrolled studies were not confirmed in subsequent randomized, controlled studies with longer follow-up. Cardiac resynchronization with novel biventricular (left and right ventricular) pacing systems has resulted in hemodynamic and functional benefits in patients with congestive heart failure and an underlying intraventricular conduction delay. Improvements in cardiac index, systolic blood pressure, and functional class have been reported with biventricular pacing, both acutely and at more than 1 year of follow-up. These encouraging preliminary results with biventricular pacing in patients with congestive heart failure will be validated in two prospective, randomized, controlled trials, Multicenter InSync Randomized Clinical Evaluation (MIRACLE) and Comparison of Medical Therapy, Pacing, and Defibrillation in Chronic Heart Failure (COMPANION). These studies are designed to evaluate the long-term efficacy of biventricular pacing in improving exercise capacity and in reducing morbidity and mortality in patients with advanced, symptomatic congestive heart failure. (c)2001 by CHF, Inc. PMID:11828152

Wong, K-L; Kocovic, D Z; Loh, E

324

Large Left Atrial Myxoma with Severe Mitral Regurgitation  

PubMed Central

Cardiac myxomas are primary cardiac tumors. In some cases of atrial myxoma, the standard left atriotomy alone does not enable safe tumor resection and easy access to the mitral valve. We report the cases of 2 patients with huge left atrial myxomas associated with severe mitral valve regurgitation who underwent an inverted T-shaped biatrial incision for tumor excision and mitral repair. This approach reduces tumor fragmentation and permits good mitral valve exposure.

Davoli, Giuseppe; Muzzi, Luigi; Lucchese, Gianluca; Uricchio, Nicola; Chiavarelli, Mario

2006-01-01

325

Left atrial myxoma prolapsing into the left ventricle. Case report and review of the literature.  

PubMed

Cardiac myxomas are rare tumors which may present differently. Left atrial myxoma is an entity from anatomopathological and clinical aspects. To the best of our knowledge, only 2 cases of infected left atrial myxomas treated surgically have been reported in the last 6 years. Herein, we present a patient with a left atrial myxoma prolapsing into the left ventricle in the diastolic phase, which was infected with Streptococcus viridans. Combined therapy, consisting of surgical management and antimicrobial therapy, was used. Clinical presentation, diagnosis and treatment are reviewed. PMID:15608446

Karachalios, G; Bablekos, G; Karachaliou, I; Zoganas, L; Charalabopoulos, A; Charalabopoulos, K

2004-12-08

326

Cardiac motion simulator for tagged MRI  

Microsoft Academic Search

Describes a computational simulator for use in cardiac imaging using tagged magnetic resonance imaging. The simulator incorporates a 13-parameter model of left-ventricular motion due to Arts et al. (1992) and applies it to a confocal prolate spherical shell, resembling the shape of the left ventricle. Using parameters determined in other work, our model can be made to assume a configuration

Edo Waks; Jerry L. Prince; Andrew S. Douglas

1996-01-01

327

A Teenager with Marfan Syndrome and Left Ventricular Noncompaction  

Microsoft Academic Search

We report a teenager with Marfan syndrome who presented to Cincinnati Children’s Hospital Medical Center as part of a preoperative\\u000a evaluation for an orthopedic procedure after asymptomatic arrhythmia was recognized. Continuous cardiac monitoring showed\\u000a frequent premature ventricular contractions and nonsustained runs of ventricular tachycardia. Cardiac magnetic resonance imaging\\u000a showed left ventricular noncompaction (LVNC), prompting insertion of an implantable cardiac defibrillator.

David Kwiatkowski; Sean Hagenbuch; Richard Meyer

2010-01-01

328

Pulmonary metastatic chondrosarcoma with massive extension into left atrium and left ventricle: outcome of surgical management in emergency.  

PubMed

We report a case of metastatic chondrosarcoma to the lung that invaded the right inferior pulmonary vein with massive cardiac extension and presented with an acute heart failure. CT scan showed a large mass of the right lower lobe which invaded and filled almost all the left atrium with an extension into left ventricle through the mitral valve. Surgical resection was performed in emergency. The patient is still alive 4 months after development of cardiac symptoms and surgery. PMID:23999561

Rodriguez, Arnaud; Roubertie, François; Thumerel, Matthieu; Jougon, Jacques

2013-09-02

329

Typical cardiac magnetic resonance imaging findings of cardiac amyloidosis.  

PubMed

We report the case of a 62-year-old man who presented with shortness of breath, lower extremity edema and clinical signs of congestive heart failure. Transthoracic echocardiography demonstrated concentric left ventricular hypertrophy with severe diastolic dysfunction and biatrial enlargement. After aggressive diuresis and clinical improvement, a cardiac magnetic resonance imaging (CMR) examination was performed. The study confirmed the presence of concentric left ventricular hypertrophy with borderline systolic function and impaired diastolic function. Delayed contrast-enhanced imaging indicated diffuse enhancement and lack of adequate signal suppression of the left ventricular myocardium, suggesting the diagnosis of infiltrative heart disease. Rectal biopsy confirmed the diagnosis of amyloidosis. This report presents the typical noninvasive imaging findings of cardiac amyloidosis. PMID:20876061

Floros, Georgios V; Karatzis, Emmanouil N; Andreou, John; Danias, Peter G

330

Gender Differences in Postinfarction Left Ventricular Remodeling  

Microsoft Academic Search

Objective: Previous studies suggest that gender affects the adaptive responses of the heart to some forms of cardiac overload. It is unknown whether gender influences left ventricular (LV) remodeling after myocardial infarction (MI). Methods: We performed transthoracic echocardiographic-Doppler examinations in age-matched male (n = 17) and female (n = 16) rats before, and 1 and 6 weeks after transmural MI

Sheldon E. Litwin; Sarah E. Katz; Christine M. Litwin; James P. Morgan; Pamela S. Douglas

1999-01-01

331

Association between Circulating Fibroblast Growth Factor 23, ?-Klotho, and the Left Ventricular Ejection Fraction and Left Ventricular Mass in Cardiology Inpatients  

PubMed Central

Background Fibroblast growth factor 23 (FGF23), with its co-receptor Klotho, plays a crucial role in phosphate metabolism. Several recent studies suggested that circulating FGF23 and ?-Klotho concentrations might be related to cardiovascular abnormalities in patients with advanced renal failure. Purpose Using data from 100 cardiology inpatients who were not undergoing chronic hemodialysis, the association of circulating levels of FGF23, ?-Klotho, and other calcium-phosphate metabolism-related parameters with the left ventricular ejection fraction (LVEF) and left ventricular mass (LVM) was analyzed. Methods and Results LVEF was measured using the modified Simpson method for apical 4-chamber LV images and the LVM index (LVMI) was calculated by dividing the LVM by body surface area. Univariate analysis showed that log transformed FGF23, but not that of ?-Klotho, was significantly associated with LVEF and LVMI with a standardized beta of ?0.35 (P<0.001) and 0.26 (P<0.05), respectively. After adjusting for age, sex, estimated glomerular filtration rate, and serum concentrations of intact parathyroid hormone, and 25-hydroxyvitamin D as covariates into the statistical model, log-transformed FGF23 was found to be a statistically positive predictor for decreased left ventricular function and left ventricular hypertrophy. Conclusions In cardiology department inpatients, circulating FGF23 concentrations were found to be associated with the left ventricular mass and LVEF independent of renal function and other calcium-phosphate metabolism-related parameters. Whether modulation of circulating FGF23 levels would improve cardiac outcome in such a high risk population awaits further investigation.

Shibata, Kensaku; Fujita, Shu-ichi; Morita, Hideaki; Okamoto, Yusuke; Sohmiya, Koichi; Hoshiga, Masaaki; Ishizaka, Nobukazu

2013-01-01

332

Using the Nova target chamber for high-yield targets  

SciTech Connect

The existing 2.2-m-radius Nova aluminum target chamber, coated and lined with boron-seeded carbon shields, is proposed for use with 1000-MJ-yield targets in the next laser facility. The laser beam and diagnostic holes in the target chamber are left open and the desired 10/sup -2/ Torr vacuum is maintained both inside and outside the target chamber; a larger target chamber room is the vacuum barrier to the atmosphere. The hole area available is three times that necessary to maintain a maximum fluence below 12 J/cm/sup 2/ on optics placed at a radius of 10 m. Maximum stress in the target chamber wall is 73 MPa, which complies with the intent of the ASME Pressure Vessel Code. However, shock waves passing through the inner carbon shield could cause it to comminute. We propose tests and analyses to ensure that the inner carbon shield survives the environment. 13 refs.

Pitts, J.H.

1987-09-28

333

Preload sensitivity in cardiac assist devices.  

PubMed

With implantable cardiac assist devices increasingly proving their effectiveness as therapeutic options for end-stage heart failure, it is important for clinicians to understand the unique physiology of device-assisted circulation. Preload sensitivity as it relates to cardiac assist devices is derived from the Frank-Starling relationship between human ventricular filling pressures and ventricular stroke volume. In this review, we stratify the preload sensitivity of 17 implantable cardiac assist devices relative to the native heart and discuss the effect of preload sensitivity on left ventricular volume unloading, levels of cardiac support, and the future development of continuous-flow total artificial heart technology. PMID:23272869

Fukamachi, Kiyotaka; Shiose, Akira; Massiello, Alex; Horvath, David J; Golding, Leonard A R; Lee, Sangjin; Starling, Randall C

2012-12-25

334

Transplantation of Engineered Cardiac Muscle Flaps in Syngeneic Rats  

PubMed Central

Cardiac tissue engineering offers the prospect of a novel treatment for acquired or congenital heart defects. Previously, our studies have shown a significant mass of vascularized cardiac tissue can be generated using a vascularized tissue engineering chamber approach in nude rats. In this present study, syngeneic rats were investigated as an animal model for cardiac tissue engineering using the arteriovenous loop (AVL) chamber in the presence of a functional immune system. Neonatal cardiomyocytes implanted into the AVL chamber survived and assembled into a contractile flap confirming the basic features we previously showed in growing a cardiac construct. There was no significant loss of the assembled cardiac muscle from immune response. The engineered cardiac muscle flaps (ECMFs) formed were transplanted to the neck vessels of the same animal using a microsurgical technique, and all transplanted tissues remained contractile. The cardiac muscle volume of the control and transplant groups was estimated with histomorphometry using desmin and ?-sarcomeric actin immunostaining, and there were no significant differences between the two groups. Finally, utilizing a novel model of transplantation, the ECMFs were transplanted to the heart of a recipient syngeneic rat as a vascularized tissue. The cardiac muscle within the transplanted ECMF was shown to survive and remain contractile for the 4-week post-transplantation period, and importantly, the cardiomyocytes retained the elongated, striated appearance of a mature phenotype. This study demonstrated the proof of concept for transplanting tissue-engineered cardiac muscle as a vascularized cardiac construct.

Tee, Richard; Dusting, Gregory J.; Liu, Guei-Sheung; Choi, Yu Suk; Hsiao, Sarah Tzu-Feng; Dilley, Rodney J.

2012-01-01

335

Cardiac sarcoidosis.  

PubMed

Cardiac sarcoidosis is a rare entity and may be difficult to diagnose prior to cardiac surgery. We review the imaging and diagnostic studies necessary to make the diagnosis and discuss therapeutic algorithms to manage this disease. doi: 10.1111/jocs.12163 (J Card Surg 2013;28:525-528). PMID:23844704

Zacek, Pavel; Omran, Nedal; Chek, James L; Krbal, Lukas; Vojacek, Jan; Harrer, Jan

2013-07-12

336

Internal combustion chamber  

SciTech Connect

In combination with a high-powered reciprocating piston internal combustion engine, an internal combustion cylinder assembly is described comprising: a cylinder head made of weldable material; a cylinder liner for containing and guiding a reciprocating piston of the engine, a coolant jacket adapted to receive a cooling fluid, mounted on and surrounding the cylinder liner, the jacket being attached to the cylinder head and detachably supported by the cylinder liner, and forming a cooling chamber around the cylinder liner; means to supply the cooling fluid to the cooling chamber and to discharge the cooling fluid therefrom.

Schmitz, D.L.

1988-03-08

337

Inducibility of life-threatening ventricular arrhythmias is related to maximum left ventricular thickness and clinical markers of sudden cardiac death in patients with hypertrophic cardiomyopathy attributable to the Asp175Asn mutation in the ?-tropomyosin gene  

Microsoft Academic Search

We investigated inducibility of life-threatening arrhythmias with programmed ventricular stimulation (PVS) in relation to clinical markers of sudden cardiac death (SCD) in subjects with hypertrophic cardiomyopathy (HCM) attributable to the Asp175Asn mutation in the ?-tropomyosin gene (TPM1-Asp175Asn). PVS was performed with up to three extrastimuli and distribution of markers of SCD was evaluated in 21 adult subjects with the TPM1-Asp175Asn. Sustained

A. Hedman; J. Hartikainen; E. Vanninen; T. Laitinen; P. Jääskeläinen; M. Laakso; K. Peuhkurinen; J. Kuusisto

2004-01-01

338

A Randomized Trial of On-Pump Beating Heart and Conventional Cardioplegic Arrest in Coronary Artery Bypass Surgery Patients With Impaired Left Ventricular Function Using Cardiac Magnetic Resonance Imaging and Biochemical Markers  

Microsoft Academic Search

Background—Beating heart coronary artery bypass grafting (CABG) improves early postoperative cardiac function in patients with normal ventricular function, but its effect in patients with impaired function is uncertain. We compared a novel hybrid technique of on-pump beating heart CABG (ONBEAT) with conventional on-pump CABG (ONSTOP) in patients with impaired ventricular function. Methods and Results—In a single-center randomized trial, 50 patients

Tammy J. Pegg; Joseph B. Selvanayagam; Jane M. Francis; Theodoros D. Karamitsos; Zoe Maunsell; Ly-Mee Yu; Stefan Neubauer; David P. Taggart

2011-01-01

339

[Cardiac radiology].  

PubMed

From the beginning of the era of X-rays, cardiac radiology has become a target of this new technique. Early pioneers, Ciegem, Rieder, Rosenthal, Williams rapidly accumulated extensive experience with fluoroscopy and radiography and publications on cardiac diseases as soon as 1899 and 1901 and 1902. The next step in cardiac diagnosis was achieved by Forsmann in 1929, with the first attempt at cardiac catheterization and angiocardiography. Many clinicians, Moniz, Reboul, Rousthoi contributed to the development of the technique between 1930 and 1940. A further turning point came in 1941 when Cournand demonstrated that cardiac catheterization was a safe method in man. In the technical field major progress came from Scandinavia were rapid filming was born. The management of ischaemic disease, changed dramatically with the demonstration of coronary anatomy, largely due to Sones, Judkins and Amplatz. A further progress was initiated in 1977 by Gruentzig who invented balloon angioplasty. PMID:8550395

Struyven, J

1995-10-01

340

Three-dimensional modeling and flow patterns determination in the left ventricle using computational fluid dynamics  

Microsoft Academic Search

A realistic model of the left ventricle of the heart was constructed using a cast from a dog heart. The purpose of this investigation was to determine the blood flow in the left ventricle in both systole and diastole and to understand what the effect of a previous cardiac cycle was on the next cardiac cycle. Runs done with an

Tad W. Taylor; Takami Yamaguchi

1994-01-01

341

Left Ventricular Mass, Stroke Volume, and Ouabain-Like Factor in Essential Hypertension  

Microsoft Academic Search

Many patients with essential hypertension (EH) exhibit increased left ventricular mass. Similarly, elevated circulating levels of an endogenous ouabainlike factor (OLF) have been described in some but not all patients with EH. Moreover, ouabain has a hypertrophic influence on isolated cardiac myocytes. Accordingly, we investigated relationships among plasma OLF, left ventricular mass, and cardiac function in patients with EH. Plasma

Paolo Manunta; Paola Stella; Rodolfo Rivera; Daniele Ciurlino; Daniele Cusi; Mara Ferrandi; John M. Hamlyn; Giuseppe Bianchi

342

Adenovirus-mediated delivery of relaxin reverses cardiac fibrosis.  

PubMed

We have evaluated the effectiveness of systemic adenovirally delivered mouse relaxin on reversing fibrosis in a transgenic murine model of fibrotic cardiomyopathy due to beta(2)-adrenergic receptor (beta(2)AR) overexpression. Recombinant adenoviruses expressing green fluorescent protein (Ad-GFP), rat relaxin (Ad-rRLN) and mouse relaxin (Ad-mRLN) were generated and Ad-rRLN and Ad-mRLN were demonstrated to direct the expression of bioactive relaxin peptides in vitro. A single systemic injection of Ad-mRLN resulted in transgene expression in the liver and bioactive relaxin peptide in the plasma. Ad-mRLN, but not Ad-GFP, treatment reversed the increased left ventricular collagen content in beta(2)AR mice to control levels without affecting collagen levels in other heart chambers or in the lung and kidney. Hence a single systemic injection of adenovirus producing mouse relaxin reverses cardiac fibrosis without adversely affecting normal collagen levels in other organs and establishes the potential for the use of relaxin gene therapy for the treatment of cardiac fibrosis. PMID:17961912

Bathgate, R A D; Lekgabe, E D; McGuane, J T; Su, Y; Pham, T; Ferraro, T; Layfield, S; Hannan, R D; Thomas, W G; Samuel, C S; Du, X-J

2007-09-22

343

Left ventricular ejection fraction measured with Doppler color flow mapping techniques.  

PubMed

To determine if left ventricular (LV) ejection fraction (EF) can be accurately measured from the color Doppler examination, 11 patients (aged 0.4 to 22 years) underwent 2-dimensional and color Doppler examinations within 24 hours of cardiac catheterization. With use of a biplane Simpson's rule, LV end-diastolic volume, end-systolic volume and EF were measured from cineangiograms, 2-dimensional echocardiograms and color Doppler examinations. The 2-dimensional echocardiographic and color Doppler measurements were obtained from apical 4-chamber and long-axis views. The color Doppler examinations were performed by placing the color sector over the left ventricle only. The velocity scale was set at the lowest possible Nyquist limit (less than 0.17 m/s), and the highest possible carrier frequency was used to obtain this limit. With these settings, all flow signals in the LV chamber were aliased so that the entire chamber was filled with mosaic color Doppler signals. Motion of the surrounding LV walls gave rise to nonaliased (pure red-blue) signals. With use of an off-line analysis system equipped with a color frame grabber, the border of the mosaic color flow area was traced to obtain volumes and EF. End-diastolic and end-systolic volumes measured with color Doppler correlated well with those measured from 2-dimensional echocardiography (r = 0.99, standard error of the estimate [SEE] = 11.9 ml; r = 0.99, SEE = 4.4 ml, respectively) and cineangiography (r = 0.92, SEE = 16.8 ml; r = 0.90, SEE = 9.9 ml, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1877485

Bengur, A R; Snider, A R; Vermilion, R P; Freeland, J C

1991-09-01

344

Programming an optimal atrioventricular interval in a dual chamber pacemaker regional population.  

PubMed

Background: Since the introduction of the dual chamber pacemaker (DDDR) in the early 1980s, researchers have repeatedly discussed and attempted to optimize the atrioventricular (AV) interval, in order to increase the cardiac performance of pacemaker patients. Nominal AV delay in a DDDR is not, by hemodynamics, the best option for the majority of patients with AV conduction disorders. Our research is suggesting a simplified approach to define an optimal AV delay in a DDDR pacemaker population on the use of the programming electrocardiogram (ECG) at follow-up.Methods: The study enrolled 55 consecutive patients (67.28 ± 1.03 years, 36 male) with an initial dual chamber pacemaker implanted for complete and second degree AV block between 2005-2010. Optimal AV delay was achieved by programming an additional delay of 95 ms, to the medium value of the interval between atrial pacing spike to the end of P wave or to the width of intrinsic P wave, on the ECG of the programming device. At discharge, shortly after the implant procedure, the patients were examined by Doppler echocardiography, during nominal and optimal AV delay pacing measuring systolic and diastolic left ventricular function parameters.Results: Compared with the nominal AV delay settings, the left ventricular end diastolic volume did not changed (from 112.3 ± 2.3 ml to 112.9 ± 2.3 ml), the end systolic volume decreased (from 59.8 ± 1.7 ml to 50.9 ± 1.3 ml, p<0.01) after adjusted the AV delay, followed by an increased left ventricle ejection fraction (from 61.07 ± 0.18 % to 65.46 ± 0.13 %, p<0.001) and isovolumic relaxation time decreased (from 102.7 ± 1.9 ms to 97 ± 2 ms, p<0.05). E wave velocity, A wave velocity and E/A ratio were not significantly changed.Conclusion: AV delay adjusted by programmer ECG in a follow-up session of an implantable device is a simple and useful method used in our laboratory as a resource for ventricular pacing optimization and hemodynamic improvement in patients with a dual chamber pacemaker (DDDR). PMID:22879840

Statescu, Cristian; Sascau, Radu A; Maciuc, Vasile; Arsenescu Georgescu, Catalina

2011-10-01

345

Impact of heart failure and left ventricular systolic dysfunction on quality of life. A cross-sectional study comparing common chronic cardiac and medical disorders and a representative adult population  

Microsoft Academic Search

Background Heart failure and left ventricular systolic dysfunction (LVSD) are increasingly common disorders, with outcomes worse than many cancers. Evidence-based therapies, such as ACE inhibitors and beta-blockers, improve prognosis and symptoms, and reduce healthcare expenditure. However, despite the high prevalence and malignant prognosis, few studies have reported the impact of heart failure and LVSD on overall quality of life and,

F. D. R. Hobbs; J. E. Kenkre; A. K. Roalfe; R. C. Davis; R. Hare; M. K. Davies

2002-01-01

346

Simultaneous left atrium volume tracking from echocardiographic movies  

Microsoft Academic Search

Left ventricular (LV) function evaluation is an integral part of every echocardiographic examination of the heart. Left atrial (LA) evaluation provides valuable clinical information that can contribute greatly to LV function evaluation. An automatic method for simultaneous tracking of LV and LA volumes through cardiac cycle is presented. The proposed method provides an extended framework for LV function analysis.

M. Yaacobi; N. Liel-Cohen; H. Guterman

2008-01-01

347

Massive hiatus hernia mimicking a left atrial mass.  

PubMed

Echocardiography is the investigational tool of choice for identifying cardiac masses. However, extracardiac masses may lead to a misdiagnosis. We present a unique case of a massive hiatus hernia in a 93 year-old woman, compressing on the left atrium, mimicking a left atrial mass. Echocardiographic features suggestive of a hiatus hernia are discussed. PMID:23369345

Lim, Han S; Leong, Darryl P; Alasady, Muayad

2013-01-28

348

Left ventricular assist devices and the slippery slope of ageism  

Microsoft Academic Search

The use of left ventricular assist devices is growing each year, as is the size of the United Network for Organ Sharing cardiac waiting pool. Notably, the geriatric waiting pool (age 65 and older), although small, is growing each year and this growth is predicted to increase as geriatric population projection curves soar. While left ventricular assist devices have clinically

Katrina A Bramstedt

2001-01-01

349

Cardiac rupture from blunt trauma with atrial septal defect.  

PubMed

A review of the literature disclosed 63 survivors of cardiac chamber rupture from blunt trauma, with no mention of associated atrial septal defect. I treated a 17-year-old girl and a 33-year-old man who survived cardiac rupture from motor vehicle accidents, both of whom were discovered postoperatively on echocardiography to have atrial septal defects. PMID:1550485

Baumgartel, E D

1992-03-01

350

Bubble Chamber Site  

NSDL National Science Digital Library

This substantial site features a large number of photos of bubble chamber (BC) tracks, many with a discussion of the physics. There is a description of how the BC works and also useful tutorial on reading BC pictures. The high quality of the images and the explanations of the events that are shown make this site especially valuable.

2008-06-11

351

Review of straw chambers  

SciTech Connect

This is a review of straw chambers used in the HRS, MAC, Mark III, CLEO, AMY, and TPC e{sup +}e{sup {minus}} experiments. The straws are 6--8 mm in diameter, operate at 1--4 atmospheres and obtain resolutions of 45--100 microns. The designs and constructions are summarized and possible improvements discussed.

Toki, W.H.

1990-03-01

352

Liquid Wall Chambers  

SciTech Connect

The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

Meier, W R

2011-02-24

353

Cardiac outflow tract anomalies.  

PubMed

The mature outflow tract (OFT) is, in basic terms, a short conduit. It is a simple, although vital, connection situated between contracting muscular heart chambers and a vast embryonic vascular network. Unfortunately, it is also a focal point underlying many multifactorial congenital heart defects (CHDs). Through the use of various animal models combined with human genetic investigations, we are beginning to comprehend the molecular and cellular framework that controls OFT morphogenesis. Clear roles of neural crest cells (NCC) and second heart field (SHF) derivatives have been established during OFT formation and remodeling. The challenge now is to determine how the SHF and cardiac NCC interact, the complex reciprocal signaling that appears to be occurring at various stages of OFT morphogenesis, and finally how endocardial progenitors and primary heart field (PHF) communicate with both these colonizing extra-cardiac lineages. Although we are beginning to understand that this dance of progenitor populations is wonderfully intricate, the underlying pathogenesis and the spatiotemporal cell lineage interactions remain to be fully elucidated. What is now clear is that OFT alignment and septation are independent processes, invested via separate SHF and cardiac neural crest (CNC) lineages. This review will focus on our current understanding of the respective contributions of the SHF and CNC lineage during OFT development and pathogenesis. WIREs Dev Biol 2013, 2:499-530. doi: 10.1002/wdev.98 For further resources related to this article, please visit the WIREs website. PMID:24014420

Neeb, Zachary; Lajiness, Jacquelyn D; Bolanis, Esther; Conway, Simon J

2013-02-19

354

Repolarization Changes Underlying Long-Term Cardiac Memory Due to Right Ventricular Pacing: Noninvasive Mapping with ECGI  

PubMed Central

Background Cardiac memory refers to the observation that altered cardiac electrical activation results in repolarization changes that persist after the restoration of a normal activation pattern. Animal studies, however, have yielded disparate conclusions both regarding the spatial pattern of repolarization changes in cardiac memory and the underlying mechanisms. This study was undertaken to produce three dimensional images of the repolarization changes underlying long-term cardiac memory in humans. Methods and Results Nine adult subjects with structurally normal hearts and dual-chamber pacemakers were enrolled in the study. Non-invasive electrocardiographic imaging (ECGI) was used before and after one month of ventricular pacing to reconstruct epicardial activation and repolarization patterns. Eight subjects exhibited cardiac memory in response to ventricular pacing. In all subjects, ventricular pacing resulted in a prolongation of the activation recovery interval (a surrogate for action potential duration) in the region close to the site of pacemaker-induced activation from 228.4±7.6 ms during sinus rhythm to 328.3±6.2 ms during cardiac memory. As a consequence, increases are observed in both apical-basal and right-left ventricular gradients of repolarization resulting in a significant increase in the dispersion of repolarization. Conclusions These results demonstrate that electrical remodeling in response to ventricular pacing in human subjects results in action potential prolongation near the site of abnormal activation and a marked dispersion of repolarization. This dispersion of repolarization is potentially arrhythmogenic and, intriguingly, was less evident during continuous RV pacing, suggesting the novel possibility that continuous RV pacing at least partially suppresses pacemaker-induced cardiac memory.

Marrus, Scott B.; Andrews, Christopher M.; Cooper, Daniel H.; Faddis, Mitchell N.; Rudy, Yoram

2012-01-01

355

Cardiac considerations in the triathlete.  

PubMed

The cardiac adaptation to exercise training produces a variety of adaptations in cardiac size, shape, and function. To further define these changes and to investigate the effects of maximal conditioning, we studied ultraendurance triathletes training for the Hawaii Ironman Triathlon using echocardiography, Doppler ultrasound, and electrocardiography. In this population, the left ventricle (LV) was of normal size but had increased wall thickness and mass. Systolic function was normal and diastolic function was normal or supernormal (increased ratio of rapid to atrial LV filling velocities). The finding of a pattern of concentric hypertrophy was reinforced by a close relationship between submaximal exercise systolic blood pressure and LV mass (r = 0.88). Examination of valvular function by Doppler ultrasound revealed significantly increased prevalences of mitral and tricuspid regurgitation in athletes, with 91% of athletes (vs 38% of controls) having regurgitation detected in at least one cardiac valve. Analysis of athletes using standard electrocardiographic criteria for the detection of left ventricular hypertrophy showed that these criteria did not reliably detect increased mass. However, changes such as marked QRS prolongation and nonvoltage criteria for LV hypertrophy and RV hypertrophy may be useful in separating physiologic from pathologic hypertrophy. Our studies provide additional descriptions of cardiac changes produced by ultraendurance exercise training and suggest that the hemodynamic load imposed by exercise may be a contributing cause to physiologic hypertrophy. Much yet remains to be learned about the cardiac adaptation to exercise training. PMID:2691833

Douglas, P S

1989-10-01

356

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-10-17

357

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-06-27

358

72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR AND CANAL (LOCATION T) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

359

Long-Term Results of Complex Left Ventricular Reconstruction Surgery  

PubMed Central

Left ventricular reconstruction is advocated as a surgical option for patients with severe congestive heart failure. Despite initial enthusiasm for this procedure, reports of long-term results are sparse. Herein, we describe a particularly gratifying case of left ventricular reconstruction in a 43-year-old man, who continues to have excellent left ventricular function 10 years postoperatively. This approach may be a reasonable alternative to cardiac transplantation in patients who lack other treatment options.

Letsou, George V.; Forrester, Matthew; Frazier, O. H.

2011-01-01

360

Congenital aneurysm of the left atrium.  

PubMed

Isolated left atrial (LA) aneurysm is a rare condition, whereas LA aneurysm secondary to other causes is a fairly common condition. A case of large left atrial aneurysm presented with features of heart failure with cardiac arrhythmia and an abnormal cardiac silhouette on chest X-ray. A 14 years old girl presented with palpitation at rest, shortness of breath, productive cough and bilateral leg swelling for last 8 months. There was no history of chest pain, hemoptysis, syncope, prolonged fever, and rheumatic fever. She was mildly anemic, had raised JVP and mild bilateral pedal edema. There was left parasternal heave, soft S1, loud P2 and a pansystolic murmur of grade 3/6 over mitral area radiating to the left axilla. ECG showed multifocal atrial tachycardia (MAT), chest X-ray showed cardiomegaly with bulging of the left heart border with upper lobe diversion. Echo-Doppler study showed hugely dilated LA (115 mm in diameter), dilated left ventricle, Grade-2+ mitral regurgitation (MR), mild tricuspid regurgitation (TR) and mild pulmonary hypertension with normal appearing mitral, aortic and tricuspid and pulmonary valves. The patient was diagnosed as a case of congenital aneurysm of LA. PMID:21240182

Rahman, M M; Pasha, K; Mohsin, M K; Marufuzzaman, S; Habib, S M; Islam, M N; Debnath, R C

2011-01-01

361

Reversal of ischaemic systolic and diastolic left ventricular dysfunction by successful coronary angioplasty in patients with non-Q wave anterior myocardial infarction.  

PubMed

The effect of PTCA on global and regional left ventricular systolic function, isovolumic relaxation, chamber and muscle stiffness were studied in 30 patients with angina pectoris, previous non-Q wave anterior myocardial infarction (AMI) and significant stenosis of the left anterior descending coronary artery (LAD). In 11 of the 30 patients the condition was stable, but it was unstable in 19. Left ventricular angiograms were obtained before and 4.85 +/- 3.67 months after PTCA. The RAO was in the 30 degree projection, with the silhouette of the left ventricle sliced into 90 regions; changes in left ventricular volume, pressure and anterior wall thickness during the full cardiac cycle, together with dp/dt were demonstrated. After PTCA, global ejection fraction increased from 68.77 +/- 5.96% to 76.57 +/- 3.18%, P < 0.001. Impaired contractility was found in 29/90 (32.2%) regions before PTCA and in 5/90 (5.6%) after PTCA, P < 0.001. The time constant of the isovolumic pressure fall decreased after PTCA (52.56 +/- 17.40 ms vs 39.61 +/- 11.26 ms, P < 0.01). Elastic chamber stiffness coefficient decreased (0.022 +/- 0.003 vs 0.008 +/- 0.004, P < 0.001) and peak rate of left ventricular filling increased (319.0 +/- 107.9 ml.min-1 vs 396.8 +/- 201.4 ml.min-1, P < 0.05) after PTCA. The muscle stiffness coefficient was within normal values before and did not change after PTCA. The study findings show that in patients with persistent angina pectoris after non-Q wave AMI, complex systolic and diastolic ischaemic dysfunction occurs. This dysfunction can be reversed after successful PTCA of LAD. PMID:7988603

Witkowski, A; Ruzy??o, W; Górecka, B; Chmielak, Z; Jodkowski, J; Dabrowski, M; Woroszylska, M; Debski, A; Demkow, M; Ciszewski, A

1994-08-01

362

11. GENERAL VIEW IN SENATE CHAMBER, FROM WEST; PAINTED GLASS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. GENERAL VIEW IN SENATE CHAMBER, FROM WEST; PAINTED GLASS WINDOW BEHIND COLUMNS DEPICTS 'THE LANDING OF DE SOTO;' MURAL TO LEFT SHOWS 'THOMAS HART BENTON'S SPEECH AT ST. LOUIS 1849;' MURAL TO RIGHT SHOWS 'PRESIDENT JEFFERSON GREETING LEWIS AND CLARK' - Missouri State Capitol, High Street between Broadway & Jefferson Streets, Jefferson City, Cole County, MO

363

Cardiac Endothelin1 Plays a Critical Role in the Functional Deterioration of Left Ventricles During the Transition From Compensatory Hypertrophy to Congestive Heart Failure in Salt-Sensitive Hypertensive Rats  

Microsoft Academic Search

Background—To investigate whether endogenous ET-1 participates in an adaptive process of left ventricular hypertrophy (LVH) or a maladaptive process from LVH to congestive heart failure (CHF), we used a Dahl salt-sensitive (DS) rat model, in which systemic hypertension caused compensated concentric LVH at the age of 11 weeks followed by marked LV dilatation and global hypokinesis at the age of

Yoshitaka Iwanaga; Yasuki Kihara; Koji Hasegawa; Koichi Inagaki; Takeshi Yoneda; Satoshi Kaburagi; Makoto Araki; Shigetake Sasayama

364

A cardiac cause for deafness.  

PubMed

We describe a case of a 49-year-old diabetic man with a history of myocardial infarction, presenting with deafness for 2 weeks. Initial assessment by otorhinolaryngologists was suggestive of sensorineural hearing loss. Subsequently, the cardiac evaluation showed an apical clot in the left ventricle. Careful neurological reassessment and a cranial MRI yielded a diagnosis of cortical deafness with auditory agnosia secondary to bilateral temporal infarcts. Doppler and MRI ruled out carotid artery thrombosis. The temporal infarcts were therefore considered to be cardioembolic in origin. Cardioembolic stroke is an important differential diagnosis for patients presenting with neurological symptoms on a background of cardiac disease. PMID:24165506

Naha, Kushal; Vivek, G; Shetty, Ranjan K; Dias, Lorraine Simone

2013-10-28

365

Cardiac Arrest  

MedlinePLUS

... too slow, or it can stop beating. Sudden cardiac arrest (SCA) occurs when the heart develops an arrhythmia that ... is blocked. There are many possible causes of SCA. They include coronary heart disease, physical stress, and ...

366

Origin of Cardiac Fibroblasts and the Role of Periostin  

PubMed Central

Cardiac fibroblasts are the most populous non-myocyte cell type within the mature heart and are required for extracellular matrix synthesis and deposition, generation of the cardiac skeleton, and to electrically insulate the atria from the ventricles. Significantly, cardiac fibroblasts have also been shown to play an important role in cardiomyocyte growth and expansion of the ventricular chambers during heart development. Although there are currently no cardiac fibroblast-restricted molecular markers, it is generally envisaged that the majority of the cardiac fibroblasts are derived from the proepicardium via epithelial-to-mesenchymal transformation. However, still relatively little is known about when and where the cardiac fibroblasts cells are generated, the lineage of each cell, and how cardiac fibroblasts move to reside in their final position throughout all four cardiac chambers. In this review we summarize the current understanding regarding the function of Periostin, a useful marker of the non-cardiomyocyte lineages, and its role during cardiac morphogenesis. Characterization of the cardiac fibroblast lineage and identification of the signals that maintain, expand and regulate their differentiation will be required to improve our understanding of cardiac function in both normal and pathophysiological states.

Snider, Paige; Standley, Kara N.; Wang, Jian; Azhar, Mohamad; Doetschman, Thomas; Conway, Simon J.

2009-01-01

367

Three chamber negative ion source  

DOEpatents

A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA); Hiskes, John R. (Livermore, CA)

1985-01-01

368

[Evaluation by means of ECG-gated cardiac blood pool scintigraphy of global and regional left ventricular function at rest and during exercise in patients with coronary artery disease (author's transl)].  

PubMed

ECG-gated cardiac blood pool scintigraphy permits a non-invasive determination of the end-diastolic and end-systolic ventricular volumes and of the ejection fraction as well as a qualitative description of regional ventricular wall motion at rest and during excercise. In 6 healthy persons a significant increase of the ejection fraction from 66 +/- 7% at rest to 78 +/- 3% during exercise (p less than 0.01) was observed. In contrast, the ejection fraction decreased in 15 out of 18 patients with coronary artery disease, with a significant (p less than 0.01) difference between patients with and without angina pectoris. Thus, the ejection fraction fell in 12 patients without angina during excercise from 60 +/- 11% to 52 +/- 11% (p less than 0.05) whereas in 6 patients with angina a decrease from 61 +/- 7% to 30 +/- 8% (p less than 0.01) was observed. This non-invasive technique makes it possible to demonstrate in a simple and safe manner changes of cardiac function during excercise in patients with coronary artery disease. PMID:733592

Sauer, E; Sebening, H; Lutilsky, L; Dressler, H; Hör, G; Pabst, H W; Blömer, H

1978-10-01

369

Combustion chamber construction  

SciTech Connect

This patent describes a combustion chamber for use in gas turbine engines is provided with a liner formed of a high temperature material. The liner includes a plurality of annular rings of high temperature material mounted by means of flexible mounting arrangement upon a high strength structural frame. As a result of this mounting arrangement, the liner is substantially isolated from structural forces associated with the combustion chamber, while the frame is substantially isolated from thermal stresses associated with the liner. The individual liner rings may be easily removed for repair or replacement without disassembling the frame and associated components. Furthermore, the decoupling of thermal and structural stresses provides longer life and more dependable operation.

Maclin, H.M.

1989-04-03

370

Combustion chamber construction  

SciTech Connect

A combustion chamber for use in gas turbine engines is provided with a liner formed of a high temperature material. The liner includes a plurality of panels of the material mounted by means of a lost motion mounting arrangement upon a high strength structural frame. As a result of this mounting arrangement, the liner is substantially isolated from structural forces associated with the combustion chamber, while the frame is substantially isolated from thermal stresses associated with the liner. For the purpose of supplying cooling air to the liner panels and frame and cooling air is passed into a plenum to cool the radially outward side of the panels. Transfer means are provided for directing the same air from the plenum to the liner inner surfaces in a cooling film. The liner mounting arrangement disclosed herein is particularly useful with difficult-to-weld liner materials (e.g., oxide dispersion strengthened materials), but its advantages commend its use with other materials also.

Maclin, H.M.

1984-11-06

371

CONTINUOUSLY SENSITIVE BUBBLE CHAMBER  

DOEpatents

A radiation detector of the bubble chamber class is described which is continuously sensitive and which does not require the complex pressure cycling equipment characteristic of prior forms of the chamber. The radiation sensitive element is a gas-saturated liquid and means are provided for establishing a thermal gradient across a region of the liquid. The gradient has a temperature range including both the saturation temperature of the liquid and more elevated temperatures. Thus a supersaturated zone is created in which ionizing radiations may give rise to visible gas bubbles indicative of the passage of the radiation through the liquid. Additional means are provided for replenishing the supply of gas-saturated liquid to maintaincontinuous sensitivity.

Good, R.H.

1959-08-18

372

Cardiac cameras.  

PubMed

Cardiac imaging with radiotracers plays an important role in patient evaluation, and the development of suitable imaging instruments has been crucial. While initially performed with the rectilinear scanner that slowly transmitted, in a row-by-row fashion, cardiac count distributions onto various printing media, the Anger scintillation camera allowed electronic determination of tracer energies and of the distribution of radioactive counts in 2D space. Increased sophistication of cardiac cameras and development of powerful computers to analyze, display, and quantify data has been essential to making radionuclide cardiac imaging a key component of the cardiac work-up. Newer processing algorithms and solid state cameras, fundamentally different from the Anger camera, show promise to provide higher counting efficiency and resolution, leading to better image quality, more patient comfort and potentially lower radiation exposure. While the focus has been on myocardial perfusion imaging with single-photon emission computed tomography, increased use of positron emission tomography is broadening the field to include molecular imaging of the myocardium and of the coronary vasculature. Further advances may require integrating cardiac nuclear cameras with other imaging devices, ie, hybrid imaging cameras. The goal is to image the heart and its physiological processes as accurately as possible, to prevent and cure disease processes. PMID:21440695

Travin, Mark I

2011-05-01

373

Combustion chamber noise suppressor  

SciTech Connect

A combustion chamber is described for a hot fog generating machine comprising a hollow cylindrical combustion chamber shell having a closure plate at one end and outlet means at the opposite end for directing hot combustion gasses to a fogging nozzle, air inlet means disposed adjacent the outlet means, fuel inlet means and ignition means mounted in the closure plate and liner means disposed concentrically within the cylindrical combustion chamber for controlling the flow of air and combustion gasses within the shell. The liner means includes a liner base having a frustroconical configuration with the smaller diameter end thereof disposed in communication with the outlet means and with the larger diameter end thereof disposed in spaced relation to the shell, circumferentially spaced, longitudinally extending fins extending outwardly from the liner base intermediate the liner base and the shell, a cylindrical liner midsection having circumferentially spaced fins extending outwardly therefrom between the midsection and the shell with the fins supporting the midsection on the larger diameter end of the liner base.

Livingston, A.M.

1986-08-19

374

Engine combustion chamber structure  

SciTech Connect

This patent describes a combustion chamber structure comprising an upper wall surface which is shaped like a pent-roof and into which an intake passage opens, a piston having on a head portion thereof a bulged portion conforming to the upper wall surface in shape, a first bowl portion which is formed substantially at the center of the bulged portion and which is substantially semispherical in shape, a pair of second bowl portions which respectively extend on opposite sides of the first bowl portion to the corresponding ends of the bulged portion of the piston along the edge of the bulged portion and are in communication with the first bowl portion, a swirl generating means which is adapted to generate a swirl of intake air in the combustion chamber when the engine load is light, and a spark plug disposed to substantially face the center of the first bowl portion from the upper wall surface; the swirl generating means being adapted to generate the swirl of intake air in a tangential direction in the combustion chamber; and the diameter of the first bowl portion being larger than the width of the second bowl portion.

Tanaka, H.

1988-09-13

375

Measurements of antimicrobial drug concentrations in renal interstitial fluid using the diffusion chamber technique  

Microsoft Academic Search

Summary A technique is described to obtain renal interstitial fluid (RIF) from rabbits after implantation of diffusion chambers with permeable membranes of 0.45 µ porosity in both kidneys. Pharmacokinetic studies were conducted two to three weeks after implantation. No difference in gentamicin concentrations, as measured microbiologically, was seen between RIF withdrawn from the left and right kidney chambers at the

A. Georgopoulos; E. Schtitze; G. Laber

1980-01-01

376

Deposition Chamber for Epitaxial Growth.  

National Technical Information Service (NTIS)

A chamber for the epitaxial deposition of thin monocrystalline semiconductors has been tested and is described. The chamber for small substrate plates is within and separated from the heating chamber (a hollow graphite cylinder which may also be made of m...

J. Eckstein P. Polivka J. Petrasek

1967-01-01

377

Temporary epicardial cardiac resynchronisation versus conventional right ventricular pacing after cardiac surgery: study protocol for a randomised control trial  

PubMed Central

Background Heart failure patients with stable angina, acute coronary syndromes and valvular heart disease may benefit from revascularisation and/or valve surgery. However, the mortality rate is increased- 5-30%. Biventricular pacing using temporary epicardial wires after surgery is a potential mechanism to improve cardiac function and clinical endpoints. Method/design A multi-centred, prospective, randomised, single-blinded, intervention-control trial of temporary biventricular pacing versus standard pacing. Patients with ischaemic cardiomyopathy, valvular heart disease or both, an ejection fraction ? 35% and a conventional indication for cardiac surgery will be recruited from 2 cardiac centres. Baseline investigations will include: an electrocardiogram to confirm sinus rhythm and measure QRS duration; echocardiogram to evaluate left ventricular function and markers of mechanical dyssynchrony; dobutamine echocardiogram for viability and blood tests for renal function and biomarkers of myocardial injury- troponin T and brain naturetic peptide. Blood tests will be repeated at 18, 48 and 72 hours. The principal exclusions will be subjects with permanent atrial arrhythmias, permanent pacemakers, infective endocarditis or end-stage renal disease. After surgery, temporary pacing wires will be attached to the postero-lateral wall of the left ventricle, the right atrium and right ventricle and connected to a triple chamber temporary pacemaker. Subjects will be randomised to receive either temporary biventricular pacing or standard pacing (atrial inhibited pacing or atrial-synchronous right ventricular pacing) for 48 hours. The primary endpoint will be the duration of level 3 care. In brief, this is the requirement for invasive ventilation, multi-organ support or more than one inotrope/vasoconstrictor. Haemodynamic studies will be performed at baseline, 6, 18 and 24 hours after surgery using a pulmonary arterial catheter. Measurements will be taken in the following pacing modes: atrial inhibited; right ventricular only; atrial synchronous-right ventricular; atrial synchronous-left ventricular and biventricular pacing. Optimisation of the atrioventricular and interventricular delay will be performed in the biventricular pacing group at 18 hours. The effect of biventricular pacing on myocardial injury, post operative arrhythmias and renal function will also be quantified. Trial Registration ClinicalTrials.gov: NCT01027299

2012-01-01

378

Left ventricular endomyocardial fibrosis in India.  

PubMed Central

Clinical, radiological, electrocardiographic, haemodynamic, and cineangiographic features of left ventricular endomyocardial fibrosis are described in 8 patients seen during the 10-year period 1965-1975. Exertional dyspnoea was the commonest presenting symptom. Mild to moderate cardiomegaly was often present. The apex beat was never forcible. A loud third heart sound over the apex and an apical early systolic murmur with late systolic decresendo were characteristic of this desease. Chest X-rays films showed left atrial enlargement and pulmonary venous congestion. A pronounced rise in left ventricular end-diastolic pressure, severe pulmonary hypertension, and low cardiac index were seen in 6. Ventriculography showed an irregular, poorly contracting left ventricle with areas of dyskinesis and large end-systolic volume. Mitral regurgitation, when present, was not severe. Images

Vijayaraghavan, G; Cherian, G; Krishnaswami, S; Sukumar, I P

1977-01-01

379

Multi-anode ionization chamber  

DOEpatents

The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

Bolotnikov, Aleksey E. (South Setauket, NY); Smith, Graham (Port Jefferson, NY); Mahler, George J. (Rocky Point, NY); Vanier, Peter E. (Setauket, NY)

2010-12-28

380

Cardiac syncope.  

PubMed

Clinicians who diagnose and manage epilepsy frequently encounter diagnoses of a nonneurological nature, particularly when assessing patients with transient loss of consciousness (T-LOC). Among these, and perhaps the most important, is cardiac syncope. As a group, patients with cardiac syncope have the highest likelihood of subsequent sudden death, and yet, unlike sudden unexpected death in epilepsy (SUDEP) for example, it is the norm for these tragic occurrences to be both easily predictable and preventable. In the 12 months following initial presentation with cardiac syncope, sudden death has been found to be 6 times more common than in those with noncardiac syncope (N Engl J Med 309, 1983, 197). In short, for every patient seen with T-LOC, two fundamental aims of the consultation are to assess the likelihood of cardiac syncope as the cause, and to estimate the risk of future sudden death for the individual. This article aims to outline for the noncardiologist how to recognize cardiac syncope, how to tell it apart from more benign cardiovascular forms of syncope as well as from seizures and epilepsy, and what can be done to predict and prevent sudden death in these patients. This is achieved through the assessment triad of a clinical history and examination, risk stratification, and 12-lead electrocardiography (ECG). PMID:23153208

Anderson, Joseph; O'Callaghan, Peter

2012-12-01

381

Left ventricular bullet embolus: a case report and review of the literature.  

PubMed

Missile embolization to the heart occurs infrequently in penetrating trauma. The lack of a concentrated experience at any single institution contributes to the controversies pertaining to diagnostic and therapeutic approaches to management. The objective of this study was to describe a case of a left ventricular bullet embolus and provide a detailed diagnostic and therapeutic framework for management of intracardiac projectiles. Initial management of a patient with suspected intracardiac projectiles is dictated by his or her hemodynamic status. Unstable patients generally require operative intervention. In the stable patient, associated injuries must be sought. Localization of the projectile can be aided by echocardiogram, fluoroscopy, or angiography. Definitive management is individualized, and can range from observation to percutaneous or operative extraction. The decision depends on the cardiac chamber involved, the patients' symptoms, and the projectile's size, shape, and location within the chamber. Missile embolus to the heart is an infrequent occurrence, but when found presents a diagnostic and therapeutic challenge. Management strategies should be individualized. A detailed management algorithm is provided. PMID:18614325

Galante, Joseph; London, Jason A

2008-07-09

382

[Left atrial myxoma with a coronary artery steal syndrome due to the coronary artery to left atrial fistula; report of a case].  

PubMed

A 73-year-old woman with dyspnea was diagnosed with a left atrial myxoma by echocardiography. Right and left circumflex coronary angiography showed neovascularity in the tumor and the blood flow jet extending from the tumor to the left atrial cavity, which led to the steal phenomenon in the left anterior descending artery. Surgical excision of the left atrial tumor and the maze procedure were performed with a cardiopulmonary circuit. To our knowledge, this is the 1st study to report the development of the coronary artery steal syndrome due to a cardiac myxoma. Exercise testing would involve risks such as embolism and left ventricular inflow disturbance; furthermore, the presence of concomitant chest symptoms with cardiac myxoma is not rare. Therefore, preoperative coronary angiography would be used for differential diagnosis and for detecting the coronary artery disease, which is reported to be common in patient with cardiac myxomas. PMID:23575189

Sogabe, Osanori; Inokawa, Hidetoshi; Tanaka, Shin; Yamamoto, Hiroyuki; Hashimoto, Kouhei

2013-04-01

383

Mutations in the NOTCH pathway regulator MIB1 cause left ventricular noncompaction cardiomyopathy.  

PubMed

Left ventricular noncompaction (LVNC) causes prominent ventricular trabeculations and reduces cardiac systolic function. The clinical presentation of LVNC ranges from asymptomatic to heart failure. We show that germline mutations in human MIB1 (mindbomb homolog 1), which encodes an E3 ubiquitin ligase that promotes endocytosis of the NOTCH ligands DELTA and JAGGED, cause LVNC in autosomal-dominant pedigrees, with affected individuals showing reduced NOTCH1 activity and reduced expression of target genes. Functional studies in cells and zebrafish embryos and in silico modeling indicate that MIB1 functions as a dimer, which is disrupted by the human mutations. Targeted inactivation of Mib1 in mouse myocardium causes LVNC, a phenotype mimicked by inactivation of myocardial Jagged1 or endocardial Notch1. Myocardial Mib1 mutants show reduced ventricular Notch1 activity, expansion of compact myocardium to proliferative, immature trabeculae and abnormal expression of cardiac development and disease genes. These results implicate NOTCH signaling in LVNC and indicate that MIB1 mutations arrest chamber myocardium development, preventing trabecular maturation and compaction. PMID:23314057

Luxán, Guillermo; Casanova, Jesús C; Martínez-Poveda, Beatriz; Prados, Belén; D'Amato, Gaetano; MacGrogan, Donal; Gonzalez-Rajal, Alvaro; Dobarro, David; Torroja, Carlos; Martinez, Fernando; Izquierdo-García, José Luis; Fernández-Friera, Leticia; Sabater-Molina, María; Kong, Young-Y; Pizarro, Gonzalo; Ibañez, Borja; Medrano, Constancio; García-Pavía, Pablo; Gimeno, Juan R; Monserrat, Lorenzo; Jiménez-Borreguero, Luis J; de la Pompa, José Luis

2013-01-13

384

Stem corrections for ionization chambers.  

PubMed

Ionization chambers often exhibit a stem effect, caused by interactions of radiation with air near the chamber end, or with dielectric in the chamber stem or cable. These interactions contribute to the apparent measured exposure. To determine the stem efffect for several common ionization chamber systems, exposures were measured with TLD capsules placed at the center of 60Co fields of various sizes. These exposure measurements then were repeated with various ionization chamber systems, including two Victoreen R meters (25- and 100-R chambers), a Capintec 192 dosimeter with a Farmer 0.6-cm3 probe, a PTW transit dose probe, and an EG and G IC-18 probe with a Keithley 610-B electrometer. From a comparison of TLD and ionization chamber measurements of the variation in exposure rate with field size, stem corrections for the different systems were determined within 1%. PMID:1196264

Ibbott, G S; Barnes, J E; Hall, G R; Hendee, W R

385

[Radiation-induced cardiac disease].  

PubMed

Radiation-induced effects may damage various cardiac structures chronically and cause heart valve dysfunction as well as occlusive lesions of coronary and other arteries exposed to radiation. A 72-year-old woman with a history of radiation treatment after breast cancer was admitted 25 years later with symptoms of tachycardia and acute dyspnea. We found valvular thickening, medium to severe valvular dysfunction and high grade occlusive coronary artery disease in proximal portions. The left subclavian artery also was affected. Surgical treatment was required immediately. Long-term follow-up cardiac evaluation even in asymptomatic patients is mandatory to uncover cardiac injuries by radiation. To lower the risk and maximize the benefit, early intervention by valvular replacement and myocardial revascularization is indicated. Restrictive myopathy and chronic pericarditis increase risk and have to be clarified. Diagnosis in these radiation exposed patients can be made by typical findings. Echocardiography is of eminent relevancy. PMID:14634766

Andresen, H; Kaag, N; Meinhardt, A; Potratz, J

2003-11-01

386

Left Atrial Myxoma Mimicking Mitral Stenosis  

PubMed Central

Cardiac myxoma is a benign (non-malignant) neoplasm that represents the most common primary tumour of the heart. We present the case of a 36 year old woman with background hypertension who presented with features of left ventricular failure and seizures, and was found during transthoracic echocardiography to have left atrial myxoma protruding through the mitral valve orifice. She subsequently had excision of the atrial myxoma. The usefulness of early transthoracic echocardiography in any patient presenting with features of heart failure even when the aetiology seems obvious cannot be over-emphasised.

Ojji, Dike B; Mamven, Manmak H; Omonua, Odiase; Habib, Zaiyad; Osaze, Hamamatu; Sliwa, Karen

2012-01-01

387

Cardiac disease and cognitive impairment: a systematic review.  

PubMed

Cognitive impairment in cardiac patients may interfere with disease management. This review describes studies examining specific cognitive impairments in cardiac patients and studies that investigate the link between echocardiographic and cognitive measures. Executive function impairments were frequently reported in different patient groups. Also, lower cardiac output and worse left ventricular diastolic function are linked to executive function deficits. In cardiac patients, special attention should be paid to these executive function impairments in view of their role in disease management and independent living. Interventions that stimulate executive function should be encouraged and integrated in cardiac treatment protocols. PMID:22689718

Eggermont, Laura H P; de Boer, Karin; Muller, Majon; Jaschke, Artur C; Kamp, Otto; Scherder, Erik J A

2012-06-11

388

Best evidence topic - Cardiac general Does cardiac resynchronisation therapy improve survival and quality of life in patients with end-stage heart failure?  

Microsoft Academic Search

Summary A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether bi- ventricular pacing, also referred to as cardiac resynchronisation therapy (CRT), improves survival and quality of life in patients with severe (NYHA IIIyIV) symptomatic heart failure. Cardiac pacing can be achieved by stimulation of the right ventricle, left ventricle (LV

Andrew J. Turley; Shahzad G. Raja; Kareem Salhiyyah; Kumaresan Nagarajan

2010-01-01

389

Mechanisms of decreased left ventricular preload during continuous positive pressure ventilation in ARDS  

Microsoft Academic Search

Continuous positive pressure ventilation is associated with a reduction in left ventricular preload and cardiac output, but the mechanisms responsible are controversial. The decrease in left ventricular preload may result exclusively from a decreased systemic venous return due to increased pleural pressure, or from an additional effect such as decreased left ventricular compliance. To determine the mechanisms responsible, we studied

J. F. Dhainaut; J. Y. Devaux; J. F. Monsallier; F. Brunet; D. Villemant; M. F. Huyghebaert

1986-01-01

390

Prediction of Mortality Risk by Different Methods of Indexation for Left Ventricular Mass  

Microsoft Academic Search

Objectives. We sought to compare the predictive value of echocardiographically determined left ventricular hypertrophy on death from all causes and cardiac mortality using various methods of indexation for left ventricular mass.Background. Considerable controversy exists regarding the optimal method for indexing left ventricular mass to body size in the clinical setting.Methods. The study included 988 consecutive patients who had both coronary

Youlian Liao; Richard S. Cooper; Ramon Durazo-Arvizu; George A. Mensah; Jalal K. Ghali

1997-01-01

391

Measurement of peak rates of left ventricular wall movement in man. Comparison of echocardiography with angiography  

Microsoft Academic Search

Estimates of peak systolic and diastolic rates of left ventricular wall movement were made in 23 patients by echocardiography and angiocardiography. Echocardiographic measurements were calculated as the rate of change of the transverse left ventricular dimension, derived continuously throughout the cardiac cycle. These were compared with similar plots of transverse left ventricular diameter, in the same patients, derived from digitized

D G Gibson; D J Brown

1975-01-01

392

Cardiac diastolic dysfunction in conscious dogs with heart failure induced by chronic coronary microembolization.  

PubMed

Left ventricular (LV) diastolic dysfunction is a fundamental impairment in congestive heart failure (CHF). This study examined LV diastolic function in the canine model of CHF induced by chronic coronary embolization (CCE). Dogs were implanted with coronary catheters (both left anterior descending and circumflex arteries) for CCE and instrumented for measurement of LV pressure and dimension. Heart failure was elicited by daily intracoronary injections of microspheres (1.2 million, 90- to 120-microm diameter) for 24 +/- 4 days, resulting in significant depression of cardiac systolic function. After CCE, LV maximum negative change of pressure with time (dP/dt(min)) decreased by 25 +/- 2% (P < 0.05) and LV isovolumic relaxation constant and duration increased by 19 +/- 5% and 25 +/- 6%, respectively (both P < 0.05), indicating an impairment of LV active relaxation, which was cardiac preload independent. LV passive viscoelastic properties were evaluated from the LV end-diastolic pressure (EDP)-volume (EDV) relationship (EDP = be(alpha*EDV)) during brief inferior vena caval occlusion and acute volume loading, while the chamber stiffness coefficient (alpha) increased by 62 +/- 10% (P < 0.05) and the stiffness constant (k) increased by 66 +/- 13% after CCE. The regional myocardial diastolic stiffness in LV anterior and posterior walls was increased by 70 +/- 25% and 63 +/- 24% (both P < 0.05), respectively, after CCE, associated with marked fibrosis, increase in collagen I and III, and enhancement of plasminogen activator inhibitor-1 (PAI-1) protein expression. Thus along with depressed LV systolic function there is significant impairment of LV diastolic relaxation and increase in chamber stiffness, with development of myocardial fibrosis and activation of PAI-1, in the canine model of CHF induced by CCE. PMID:16877566

Gill, Robert M; Jones, Bonita D; Corbly, Angela K; Wang, Juan; Braz, Julian C; Sandusky, George E; Wang, Jie; Shen, Weiqun

2006-07-28

393

Glycogenolysis and Phosphorylase Activity of Cardiac Muscle in Hemorrhagic Shock.  

National Technical Information Service (NTIS)

The concentration of metabolic substrates in cardiac muscle and in arterial and coronary venous blood was determined in control dogs and dogs in hemorrhagic shock. Levels of lactate, pyruvate, glycogen, and phosphorylase enzyme in left ventricular muscle ...

J. Doersching V. V. Glaviano

1966-01-01

394

Treatment Related Cardiac Toxicity in Patients Treated for Breast Cancer.  

National Technical Information Service (NTIS)

Purpose: To determine the incidence dose/time-dependence and functional significance of regional cardiac perfusion abnormalities in patients with left-sided breast cancer treated with radiation therapy (RT) with and without doxorubicin. Methods: 160 patie...

L. B. Marks

2006-01-01

395

Treatment Related Cardiac Toxicity in Patients Treated for Breast Cancer.  

National Technical Information Service (NTIS)

To determine the incidence, dose/time-dependence, and functional significance of regional cardiac perfusion abnormalities in patients with left- sided breast cancer treated with radiation therapy (RT) with and without doxorubicin Methods: 126 patients und...

L. B. Marks

2003-01-01

396

Treatment Related Cardiac Toxicity in Patients Treated for Breast Cancer.  

National Technical Information Service (NTIS)

To determine the incidence, dose/time-dependence, and functional significance of regional cardiac perfusion abnormalities in patients with left- sided breast cancer treated with radiation therapy (RT) with and without doxorubicin; 153 patients underwent p...

L. B. Marks

2005-01-01

397

[Syncope as first and only sign of left atrial myxoma].  

PubMed

Myxoma is the most frequent primary heart tumor. It is localised in the left atrium in majority of cases, but each of heart chambers may be affected. Left atrial myxoma becomes symptomatic in case it leads into mitral valve obstruction, systemic embolisation or it manifests with unspecific systemic symptoms. Echocardiography is a golden standard of myxoma diagnostics. We present a case of 61-years old woman patient in whom exercise induced syncope was the first and only sign of far gone left atrial myxoma with left ventricle inflow tract obstruction, leading to mitral pseudostenosis. PMID:23461403

Samoš, M; K?azeje, M; Dvorský, J; Ková?, F; Galajda, P; Moká?, M

2013-02-01

398

Cardiac Circulation  

NSDL National Science Digital Library

This simple FlashTM animation depicts blood flow through the great vessels and chambers of the mature heart. Clicking brings up labels. A second click brings up arrows defining venous flow. A third click brings up arrows tracing the arterial flow.

PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

2009-11-20

399

Cardiac responses after norepinephrine-induced ventricular hypertrophy in rats.  

PubMed

The increase in norepinephrine (NE) blood levels in human heart failure correlates with prognosis. In this study, we determined whether continuous NE infusion alters the positive inotropic and chronotropic responses of isolated rat cardiac muscles. Osmotic minipumps were implanted subcutaneously (s.c.) in 43 adult male rats to deliver NE (160 micrograms/kg/h for 14 days); 42 rats were sham-operated. Isolated left and right atria and left and right ventricular (LV, RV) papillary muscles were prepared to measure positive inotropic or chronotropic responses to NE, phenylephrine, forskolin, dibutyryl cyclicAMP (dbcyclicAMP), and calcium chloride. NE infusion caused (a) a 22% increase in LV wet weight without altering atrial or RV wet weights; (b) an 18% decrease in maximal inotropic response to calcium chloride in LV papillary muscles only; (c) a significantly decreased peak response to NE [72 +/- 5 vs. 93 +/- 5% (sham rats) of calcium chloride] but not to forskolin or dbcyclicAMP in RV papillary muscles; (d) an increased incidence of ectopy at low concentrations of NE, forskolin, and dbcyclicAMP in LV papillary muscles; (e) no alteration in papillary muscle responses to phenylephrine but significantly increased left atrial inotropic responses [51 +/- 5 vs. 33 +/- 2% (sham rats) of calcium chloride] and right atrial chronotropic responses [30 +/- 2 vs. 18 +/- 4 (sham rats) beats/min]; and (f) a selective decrease in beta 1-adrenoceptor density in both ventricles. Thus, NE infusion causes selective LV hypertrophy; responses of compounds that increase intracellular cyclicAMP are affected to a greater extent in papillary muscles from the hypertrophied ventricle than in tissues from the other chambers of the heart. PMID:1381025

Brown, L; Sernia, C; Newling, R; Fletcher, P

1992-08-01

400

Complete heart block during cardiac catheterization in a normal individual.  

PubMed

A 44-year-old white male who developed third-degree heart block during cardiac catheterization is presented. Right heart catheterization precipitated bifascicular block, right bundle branch block with left posterior hemiblock, and resulted in third-degree heart block during the left heart procedure. It is recommended that multiple electrocardiographic lead monitoring be considered during cardiac catheterization in order to recognize more easily high-risk conduction disturbances, ie a bifascicular block pattern with frontal plane axis shifts. PMID:6509544

Baird, C L; Borst, M P; Maxfield, D L

1984-01-01

401

Cardiac emergencies.  

PubMed

The diagnosis and management of pediatric cardiac emergencies can be challenging and complicated. Early presentations are usually the result of ductal-dependent lesions and appear with cyanosis and shock. Later presentations are the result of volume overload or pump failure and present with signs of congestive heart failure. Acquired diseases also present as congestive heart failure or arrhythmias. PMID:23915599

Barata, Isabel Araujo

2013-08-01

402

Contour extraction from cardiac MRI studies using snakes  

Microsoft Academic Search

The author investigated automatic extraction of left ventricular contours from cardiac magnetic resonance imaging (MRI) studies. The contour extraction algorithms were based on active contour models, or snakes. Based on cardiac MR image characteristics, the author suggested algorithms for extracting contours from these large data sets. The author specifically considered contour propagation methods to make the contours reliable enough despite

Surendra Ranganath

1995-01-01

403

Development and Evaluation of Unilateral and Bilateral Cardiac Assist Devices.  

National Technical Information Service (NTIS)

The objective of this program is to develop and evaluate unilateral and bilateral cardiac assist devices which will ultimately be used for temporary and chronic cardiac support. A family of pumps has been developed and used as right and left heart assist ...

J. T. Keiser W. F. Bernhard

1974-01-01

404

Ultrasound-Guided Cardiac Blood Sampling of the Rabbit Fetus  

Microsoft Academic Search

The object of the study was to determine whether cardiac sampling of the rabbit fetus could be successfully accomplished with minimal procedure-related loss. Pregnant rabbit dams were randomized to undergo ultrasound-guided fetal cardiac sampling in either the left or right uterine horn at 27 days of gestation; cesarean delivery was performed the following day. Liveborn pups from unsampled uterine horns

George Saade; Leah Knudsen; Antonio Valdez-Torres; Michael A. Belfort; Helen Hsu; Shelley C. Harvey; Kathryn M. Hudson; Scott Rodkey

1994-01-01

405

Cardiac Myxoma Originating from the Anterior Mitral Valve Leaflet  

PubMed Central

Primary cardiac tumors are rare and myxoma is the most common tumor among them. Cardiac myxoma usually occurs in the left atrium. Myxoma originating from mitral valve is extremely rare. We report a case of mitral valve myxoma. The tumor originated from the anterior mitral valve leaflet. The tumor was completely removed and replacement of the mitral valve was not done.

Yoon, Jung-Han; Kim, Ji-Hyun; Sung, Young-Jun; Lee, Min-Ho; Cha, Myung-Jin; Kang, Do-Yoon; Kim, Yong-Jin

2011-01-01

406

Iran Chamber Society  

NSDL National Science Digital Library

In 2001, the Iran Chamber Society was created in order to provide a non-partisan, non-commercial, comprehensive source of information on Iran. The website's "About Us" section states that their aim is to "create a global awareness about Iranian society and eradicate the misunderstandings and misconceptions about Iranian society, and to play an educational role as well." Visitors will find the website divided up into "Art and Culture", "History", "Society" and "Iran's Guide". The "Exhibitions and Conferences" link on the right side of the homepage leads visitors to a number of exhibitions, including the fascinating "Artistic Murals of Tehran's Metro Stations", which offers a dozen pictures of the beautifully handcrafted murals made of pottery, metal, cement and other materials. The "History" section offers pictures and documents, including some disturbing graphic photos from the Iran-Iraq War in 1980-1988 that appear at the end of the Historic Periods and Events s