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Left Ventricular Dysfunction (leave + ventricular_dysfunction)
Selected AbstractsBaseline Characteristics of Patients Randomized in the Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) StudyCONGESTIVE HEART FAILURE, Issue 2 2008Cecilia Linde MD The Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) study is a randomized controlled trial currently assessing the safety and efficacy of cardiac resynchronization therapy in patients with asymptomatic left ventricular (LV) dysfunction with previous symptoms of mild heart failure. This paper describes the baseline characteristics of randomized patients; 610 patients with New York Heart Association (NYHA) class II (82.3%) heart failure or asymptomatic (NYHA class I) LV dysfunction with previous symptoms (17.7%) were randomized in 73 centers. The mean age was 62.5±11.0 years, the mean LV ejection fraction was 26.7%±7.0%, and the mean LV end-diastolic diameter was 66.9±8.9 mm. A total of 97% of patients were taking angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and 95.1% were taking ,-blockers, which were at the target dose in 35.1% of patients. Compared with previous randomized cardiac resynchronization therapy trials, REVERSE patients are on better pharmacologic treatment, are younger, and have a narrower QRS width despite similar LV dysfunction. [source] Assessment of Myocardial Viability with Dobutamine Stress Echocardiography in Patients with Ischemic Left Ventricular DysfunctionECHOCARDIOGRAPHY, Issue 1 2005Siu-Sun Yao M.D. The noninvasive assessment of myocardial viability has proved clinically useful for distinguishing hibernating and/or stunned myocardium from irreversibly injured myocardium in patients with chronic ischemic heart disease or recent myocardial infarction, with marked regional and/or global left ventricular (LV) dysfunction. Noninvasive techniques utilized for the detection of viability in asynergic myocardial regions include positron emission tomographic imaging of residual metabolic activity, single photon emission tomography (SPECT) of radioisotope uptake with thallium-201, low-dose dobutamine echocardiography assessment of inotropic reserve and myocardial contrast echocardiography for evaluation of microvascular integrity. Of these techniques, dobutamine stress echocardiography is a safe, widely available and relatively inexpensive modality for the identification of myocardial viability for risk stratification and prognosis. Low-dose dobutamine response can accurately predict improvement of dysfunctional yet viable myocardial regions, and thus identify a subset of patients whose LV function will improve following successful coronary revascularization. [source] Biocompatibility of Heparin-Coated Cardiopulmonary Bypass Circuits in Coronary Patients With Left Ventricular Dysfunction Is Superior to PMEA-Coated CircuitsJOURNAL OF CARDIAC SURGERY, Issue 6 2006Veysel Kutay M.D. The aim of this study was to evaluate the clinical effectiveness and biocompatibility of heparin-coated and poly-2-methoxyethylacrylate (PMEA)-coated CPB circuits on coronary patients with left ventricular systolic dysfunction. Methods: Thirty-six patients who underwent elective coronary artery bypass grafting were divided into two equal groups: group H (n = 18), heparin-coated; group P (n = 18), PMEA coated. Clinical outcomes, hematologic variables, cardiac enzymes, malondialdehyde (MDA), and acute phase inflammatory response (including myeloperoxidase (MPO), catalase, hsCRP, and IL-8) were analyzed perioperatively. Results: Demographic, CPB, and clinical outcome data were similar for both groups. Plasma fibrinogen, total protein, albumin, and platelet count decreased, neutrophil count, MDA, IL-8, MPO, and catalase levels increased during CPB. During CPB, MPO and catalase values were significantly higher in group P (p = 0.02 and p = 0.01) and postoperative MDA concentration was lower in group H (p = 0.03). Platelet counts were better preserved in group H during and after CPB but neutrophil count and IL-8 level did not differ between the groups. Postoperative total protein, albumin, and fibrinogen levels were higher in group H (p < 0.05). The postoperative first day levels of troponin-I, CK-MB, and CRP increased in both groups without any significant differences between the groups. Conclusions: Heparin-coated circuit provided better suppression of perioperative inflammatory markers and exhibited more favorable effects on hematologic variables than PMEA-coated circuit. [source] Exercise is Superior to Pacing for T Wave Alternans Measurement in Subjects with Chronic Coronary Artery Disease and Left Ventricular DysfunctionJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2002ERIC J. RASHBA M.D. Exercise vs Pacing for TWA Measurement.Introduction: T wave alternans (TWA) is a heart rate-dependent marker of vulnerability to ventricular arrhythmias. Atrial pacing and exercise both are used as provocative stimuli to elicit TWA. However, the prognostic value of the two testing methods has not been compared. The aim of this prospective study was to compare the prognostic value of TWA measured during bicycle exercise and atrial pacing in a large cohort of high-risk patients with ischemic heart disease and left ventricular dysfunction. Methods and Results: This was a prospective study of 251 patients with coronary artery disease and left ventricular dysfunction who were referred for electrophysiologic studies (EPS) for standard clinical indications. Patients underwent TWA testing using bicycle ergometry (exercise TWA, n = 144) and/or atrial pacing (pacing TWA, n = 178). The primary endpoint was the combined incidence of death, sustained ventricular arrhythmias, and appropriate implantable cardioverter defibrillator therapy. The predictive value of exercise and pacing TWA for EPS results and for endpoint events was determined. Exercise and pacing TWA both were significant predictors of EPS results (odds ratios 3.0 and 2.9 respectively, P < 0.02). Kaplan-Meier survival analysis of the primary endpoint revealed that exercise TWA was a significant predictor of events (hazard ratio 2.2, P = 0.03). In contrast, pacing TWA had no prognostic value for endpoint events (hazard ratio 1.1, P = 0.8). Conclusion: TWA should be measured during exercise when it is used for clinical risk stratification. EPS results may not be an adequate surrogate for spontaneous events when evaluating new risk stratification tests. [source] The Effects of Rate-Adaptive Atrial Pacing Versus Ventricular Backup Pacing on Exercise Capacity in Patients with Left Ventricular DysfunctionPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2009M.S.C.E., ROD PASSMAN M.D. Background: Atrial rate-adaptive pacing may improve cardiopulmonary reserve in patients with left ventricular dysfunction. Methods: A randomized, blinded, single-crossover design enrolled dual-chamber implantable defibrillator recipients without pacing indications and an ejection fraction ,40% to undergo cardiopulmonary exercise treadmill stress testing in both atrial rate-adaptive pacing (AAIR) and ventricular demand pacing (VVI) pacing modes. The primary endpoint was change in peak oxygen consumption (VO2). Secondary endpoints were changes in anaerobic threshold, perceived exertion, exercise duration, and peak blood pressure. Results: Ten patients, nine males, eight with New York Heart Association class I, mean ejection fraction 24 ± 7%, were analyzed. Baseline VO2 was 3.6 ± 0.5 mL/kg/min. Heart rate at peak exercise was significantly higher during AAIR versus VVI pacing (142 ± 18 vs 130 ± 23 bpm; P = 0.05). However, there was no difference in peak VO2 (AAIR 23.7 ± 6.1 vs VVI 23.8 ± 6.3 mL/kg/min; P = 0.8), anaerobic threshold (AAIR 1.3 ± 0.3 vs VVI 1.2 ± 0.2 L/min; P = 0.11), rate of perceived exertion (AAIR 7.3 ± 1.5 vs VVI 7.8 ± 1.2; P = 0.46), exercise duration (AAIR 15 minutes, 46 seconds ± 2 minutes, 54 seconds vs VVI 16 minutes, 3 seconds ± 2 minutes, 48 seconds; P = 0.38), or peak systolic blood pressure (AAIR 155 ± 22 vs VVI 153 ± 21; P = 0.61) between the two pacing modes. Conclusion: In this study, AAIR pacing did not improve peak VO2, anaerobic threshold, rate of perceived exertion, or exercise duration compared to VVI backup pacing in patients with left ventricular dysfunction and no pacing indications. [source] Frequent Premature Ventricular Complexes Originating from the Right Ventricular Outflow Tract Are Associated with Left Ventricular DysfunctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2008Yumiko Kanei M.D. Background: Recent case series have shown reversal of left ventricular (LV) dysfunction after catheter ablation of frequent premature ventricular complexes (PVCs) originating from the right ventricular outflow tract (RVOT). We conducted a retrospective study to evaluate the prevalence of patients with frequent RVOT PVCs (,10 per hour) and LV dysfunction. Methods: RVOT PVC was defined as PVC with left bundle branch block morphology and inferior axis on a 12-lead ECG. We included patients with frequent RVOT PVCs on 24-hours Holter monitor who had a recent evaluation of LV function. Patients with structural heart disease, including obstructive coronary artery disease, were excluded. Patients were divided into three groups based on the number of PVCs (<1000/24 hour, 1000,10,000/24 hour, ,10,000/24 hour), and the prevalence of LV dysfunction was evaluated in each group. Results: Our analysis included 108 patients: 24 patients had <1000PVCs/24 hour, 55 patients had 1000,10,000PVCs/24 hour, and 29 patients had ,10,000PVCs/24 hour. The prevalence of LV dysfunction was 4%, 12%, and 34%, respectively (P = 0.02). With logistic regression analysis, non-sustained ventricular tachycardia was an independent predictor of LV dysfunction with odds ratio of 3.6 (1.3,10.1). Conclusion: We demonstrated a significant association between frequent RVOT PVCs and LV dysfunction in patients without structural heart disease. [source] Performance of Phonoelectrocardiographic Left Ventricular Systolic Time Intervals and B-Type Natriuretic Peptide Levels in the Diagnosis of Left Ventricular DysfunctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2007Brian Moyers M.D. Background: Systolic time intervals measured by echocardiography and carotid artery tracings are validated methods of assessing left ventricular function. However, the clinical utility of phonoelectrocardiographic systolic time intervals for predicting heart failure using newer technology has not been evaluated. Methods: We enrolled 100 adult patients undergoing left heart catheterization. Participants underwent computerized phonoelectrocardiographic analysis, left ventricular end-diastolic pressure (LVEDP) measurement, transthoracic echocardiographic measurement of left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP) testing. The heart rate-adjusted systolic time intervals included the time from the Q wave onset to peak S1 (electromechanical activation time, EMAT), Q wave onset to peak S2 (electromechanical systole, Q-S2), and peak S1 to peak S2 (left ventricular systolic time, LVST). Left ventricular dysfunction was defined as the presence of both LVEDP >15 mmHg and LVEF <50%. Results: EMAT (r =,0.51; P < 0.0001), EMAT/LVST (r =,0.41; P = 0.0001), and Q-S2 (r =,0.39; P = 0.0003) correlated with LVEF, but not with LVEDP. An abnormal EMAT ,15 (odds ratio 1.38, P < 0.0001) and EMAT/LVST ,0.40 (OR 1.13, P = 0.002) were associated with left ventricular dysfunction. EMAT ,15 had 44% sensitivity, 94% specificity, and a 7.0 likelihood ratio for left ventricular dysfunction, while EMAT/LVST ,0.40 had 55% sensitivity, 95% specificity, and a 11.7 likelihood ratio. In patients with an intermediate BNP (100,500 pg/mL), the likelihood ratio increased from 1.1 using the BNP result alone to 11.0 when adding a positive EMAT test for predicting left ventricular dysfunction. Conclusions: Phonoelectrocardiographic measures of systolic time intervals are insensitive but highly specific tests for detecting abnormalities in objective markers of left ventricular function. EMAT and EMAT/LVST provide diagnostic information independent of BNP for detecting patients with left ventricular dysfunction. [source] Brain Natriuretic Peptide Levels and Response to Cardiac Resynchronization Therapy in Heart Failure PatientsCONGESTIVE HEART FAILURE, Issue 5 2006Reynolds M. Delgado MD The authors used brain natriuretic peptide (BNP) as a reliable marker to identify nonresponders to cardiac resynchronization therapy (CRT) in patients with advanced heart failure. The study included 70 patients with left ventricular dysfunction (mean ejection fraction, 21±4%) and left bundle branch block (QRS duration, 164±25 milliseconds) treated with CRT. The authors reviewed data on New York Heart Association functional class, baseline ejection fraction, sodium, creatinine, QRS duration, and BNP levels 3 months before and after CRT therapy. The authors compared results of 42 patients who survived (973+192 days) after CRT implantation (responders) to those of 28 patients (nonresponders) who either expired (n=21) or underwent heart transplantation (n=5) or left ventricular assist device implantation (n=2) after an average of 371+220 days. Mean BNP levels after 3 months of CRT decreased in responders from 758±611 pg/mLto 479±451 pg/mL (P=.044), while in nonresponders there was increase in BNP levels from 1191 ±466 pg/mL to 1611 ±1583; P=.046. A rise in BNP levels was associated with poor response (death or need for transplantation or left ventricular assist device and impaired long-term outcome), which makes it a good predictor to identify such patients. [source] Cardiovascular cell therapy and endogenous repairDIABETES OBESITY & METABOLISM, Issue 2008D. A. Taylor Cardiovascular disease (CVD) exceeds infection and cancer as the leading cause of death. In the USA alone, approximately a million individuals suffer an acute myocardial infarction (AMI) annually. As the prevalence of CVD risk factors (e.g. hypertension, obesity and type 2 diabetes) rises, CVD is increasing in younger individuals. Fortunately, existing therapies have improved post-AMI mortality, but in turn have increased the prevalence of post-AMI heart failure (HF). Approximately half-a-million new HF cases are diagnosed each year in the USA. In the next 25 years, up to 15% of the population over the age of 65 in the USA is projected to have HF. Therapeutic interventions that prevent/reverse atherosclerosis, prevent post-AMI HF and halt the progressive functional deterioration once HF occurs are all needed. Cell therapy , either via exogenous delivery or by endogenous mobilization of cells , may be able to do so, in part, by improving the body's capacity for repair. To date, primarily bone marrow- or blood-derived cells have been utilized after AMI to prevent left ventricular dysfunction, and skeletal myoblasts have been transplanted into failing myocardium. Preclinical studies are directed at prevention/reversal of atherosclerosis with bone marrow precursors, and ultimately at replacing failing heart with a cell-based bioartificial construct. [source] Echocardiographic Follow-Up of Patients with Takayasu's Arteritis: Five-Year SurvivalECHOCARDIOGRAPHY, Issue 5 2006María Elena Soto M.D, Ms.Sc. Takayasu's arteritis (TA) is a primary vasculitis that causes stenosis or occlusion, rarely aneurysm and distal ischemia. This study was undertaken to examine cardiovascular damage using echocardiography and determine the causes of morbid-mortality in Mexican Mestizo patients with TA. Seventy-six patients were studied by transthoracic echocardiography. Left ventricular diameters, parietal thickness, systolic function, and wall motion were analyzed, also, valvular lesions and aorta features were assessed. Thickness of the interventricular septum was 12 mm ± 3 (8,19), and that of posterior wall was 12 mm ± 2 (9,18). The average left ventricular diastolic diameter was 47 mm ± 7 (33,68) and the left ventricular systolic diameter 32 mm ± 8 (16,64). The left ventricular ejection fraction was of 57 ± 11%. Left ventricular concentric hypertrophy was found in 28 (50%) of the 56 hypertensive patients. The five-year survival of patients with left ventricular concentric hypertrophy was 80%, compared to 95% in patients without hypertrophy (P = 0.00). Abnormal wall motion was found in 15 patients. Thirty-one patients had aortic regurgitation, 19 had mitral regurgitation, 13 had tricuspid regurgitation, and 10 and pulmonary hypertension. Six patients had aneurysms of ascending aorta and 7 stenosis of descending aorta. Thirteen of 76 patients died (17%), 85% were hypertensive, and 9% also had acute myocardial infarction (AMI). Echocardiography, a noninvasive technique, shows a great utility in detection and follow-up of cardiovascular manifestations in patients with TA. New techniques, more sensitive toward detecting the early stages of left ventricular dysfunction, are promising to limit left ventricular hypertrophy development. [source] Elongation Index as a New Index Determining the Severity of Left Ventricular Systolic Dysfunction and Mitral Regurgitation in Patients with Congestive Heart FailureECHOCARDIOGRAPHY, Issue 7 2005Mehmet Yokusoglu M.D. The shape of the left ventricle is an important echocardiographic feature of left ventricular dysfunction. Progression of the mitral regurgitation and consequent left ventricular remodeling is unpredictable in heart failure. Elongation index is an index of left ventricular sphericity. The surface area of the elongated ventricle is larger than that of a spherical one. The objective of this study was to assess the relation between elongation index and the degree of mitral regurgitation along with noninvasive indices of left ventricular function. Thirty-two patients (21 male, 11 female, mean age: 57 ± 6 yrs) with congestive heart failure and mitral regurgitation were included. Patients were stratified into three groups according to vena contracta width as having mild (n = 11), moderate (n = 11) and severe mitral regurgitation (n = 10). The elongation index (EI) was considered as equal to {[(left ventricular internal area-measured) , (theoretical area of the sphere with measured left ventricular volume)]/(theoretical area of the sphere with measured left ventricular volume)}. Ejection fractions by the modified Simpson rule, dP/dt and sphericity index (SI) were also recorded. The relationship between (EI), ejection fraction, dP/dt and SI reached modest statistical significance (p < 0.05). When the EI and SI were compared, the correlation was also significant (p < 0.01). The areas under the receiver operator curve of EI and SI for discriminating dP/dt < 1000 mm Hg/s were 0.833 and 0.733, respectively. In conclusion, the elongation, which defines the shape of the left ventricle, might be related to the systolic function of the left ventricle and the degree of the mitral regurgitation. Further studies are needed to demonstrate its use in other clinical entities. [source] BNP and N-terminal proBNP are both extracted in the normal kidneyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2006J. P. Goetze Abstract Background, Increased plasma concentrations of cardiac-derived B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (proBNP) are both associated with left ventricular dysfunction. Information on the regional elimination of the peptides is, however, still scarce. We therefore examined the renal and peripheral extraction of N-terminal proBNP and BNP. Materials and methods, The study comprised 18 patients with essential arterial hypertension, 51 with cirrhosis, and 18 control patients without kidney or liver disease. All patients underwent a haemodynamic investigation with catheterization of the femoral artery and femoral and renal veins. Blood sampling from the catheters allowed determination of the arteriovenous extraction ratio of N-terminal proBNP and BNP. Results, Neither the peripheral N-terminal proBNP (13, 11, 19 pmol L,1, NS) nor the BNP plasma concentrations (4, 12, 9 pmol L,1, NS) differed between the patient groups. In addition, similar renal extractions were observed in the groups. The renal extraction of N-terminal proBNP (0·16) was not different from that of BNP (0·16). In contrast, the N-terminal proBNP extraction in the lower extremity was markedly lower compared with BNP (0·00 vs. 0·125, P = 0·007). Conclusions, A comparable renal elimination of N-terminal proBNP and BNP is contrasted by a selective extraction of BNP in the lower extremity. Our results suggest a different elimination mechanism in the renal and peripheral circulation, which partly may explain the higher N-terminal proBNP compared with BNP concentrations in normal plasma. [source] The clinical value of rapid assay for plasma B-type natriuretic peptide in differentiating congestive heart failure from pulmonary causes of dyspnoeaINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2008S.-Q. Zhao Summary Background:, B-type natriuretic peptide (BNP) is a cardiac neurohormone secreted from the cardiac ventricles in response to pressure overload. Objective:, To evaluate the optimal cutoff point of plasma BNP in diagnosing congestive heart failure (CHF). Methods:, We conducted a prospective study of 195 patients who were hospitalised with dyspnoea. Pulmonary capillary wedge pressure (PCWP) was measured with a Swan-Ganz catheterisation and plasma BNP level was obtained by a rapid immunofluorescence assay in all patients. PCWP > 12 mmHg was chosen as the golden standard for left ventricular dysfunction in this study. The subjects were divided into two groups by the criteria, one group with dyspnoea caused by CHF (n = 134) and the other caused by lung diseases (n = 61). Results:, (1) BNP cutoff point of 100 pg/ml had a sensitivity of 94.34%, a specificity of 92.13% and an accuracy of 93.33% for differentiating CHF from pulmonary dyspnoea. (2) By multiple logistic-regression analysis, measurements of BNP added significantly independent predictive power to other clinical variables in models predicting which patients had CHF. Conclusion:, A value of 100 pg/ml or more for a rapid BNP assay may be the most accurate independent predictor of the presence or absence of CHF. [source] An Ovine Model of Chronic Heart Failure: Echocardiographic and Tissue Doppler Imaging CharacterizationJOURNAL OF CARDIAC SURGERY, Issue 1 2006M.Sc., Nicolas Borenstein D.V.M. In order to validate novel surgical or pharmacological treatments, reproducible animal models of left ventricular dysfunction are necessary. In the current study, we report our data and experience with a model of toxin-induced heart failure in the sheep. Methods: Sequential intracoronary injections of doxorubicin (0.75 mg/kg) were carried out every 2 weeks until standard echocardiographic and tissue Doppler imaging detection of myocardial systolic dysfunction. The animals were assessed 1 month later and harvested. Indices of cardiac function from baseline to last day of protocol were recorded and their differences were evaluated by a Wilcoxon rank test for paired data. Results: Ten sheep received 2.5 ± 0.7 intracoronary injections of a cumulative dose of 88.8 ± 25 mg/m2 doxorubicin. All available parameters demonstrated signs of severe cardiac dysfunction with statistical significance. All hearts demonstrated severe histological lesions, some of which were consistent with doxorubicin-induced toxicity. Conclusions: The present study shows that this ovine model is reproducible and stable. It can therefore be relevant to the study of chronic heart failure. It will be incorporated in our future studies concerning novel treatments (such as cell therapy) of nonischemic dilated cardiomyopathy. [source] Limited Response to Cardiac Resynchronization Therapy in Patients with Concomitant Right Ventricular DysfunctionJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2010M.P.H., PAUL B. TABEREAUX M.D. Limited Response to CRT in Patients with RVD.,Introduction: Patients with left ventricular dysfunction (LVD) and LV dyssynchrony may respond to cardiac resynchronization therapy (CRT). However, right ventricular dysfunction (RVD) is a predictor of decreased survival in patients with LVD, and its influence on clinical response to CRT is unknown. The purpose of this study was to examine the effect of RVD on the clinical response to CRT. Methods and Results: A retrospective cohort of consecutive patients who underwent implantation of a CRT implantable cardioverter-defibrillator (ICD) were included and deemed to have RVD based on a RV ejection fraction <0.40. A lack of response to CRT was defined as: death, heart transplantation, implantation of an LV assist device, absent improvement in NYHA functional class at 6 months or hospice care. Among 130 patients included (mean age 58 ± 11 years, 68.5% male, 87.7% Caucasian, 51.5% nonischemic cardiomyopathy), 77 (59.2%) had no response to CRT as defined above. Of the nonresponders, 43 (56%) had RVD and 34 (44%) did not have RVD (P = 0.02). After adjustment for age, race, gender, cardiomyopathy type, atrial fibrillation, serum sodium, and severe mitral regurgitation, RVD (adjusted OR = 0.34, 95%CI 0.14,0.82), female gender (adjusted OR = 0.36, 95%CI 0.14,0.95), and serum creatinine (adjusted OR = 0.25, 95%CI 0.09,0.71) were independently associated with decreased odds of response to CRT. There was a significant difference in survival of patients with and without RVD after CRT (log rank P = 0.01). Conclusion: RVD represents a strong predictor of lack of clinical response to CRT in patients with CHF due to LVD and should be considered when prescribing CRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 431,435, April 2010) [source] Prospective Study of Cardiac Sarcoid Mimicking Arrhythmogenic Right Ventricular DysplasiaJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2009SMIT C. VASAIWALA M.D. Introduction: Case studies indicate that cardiac sarcoid may mimic the clinical presentation of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C); however, the incidence and clinical predictors to diagnose cardiac sarcoid in patients who meet International Task Force criteria for ARVD/C are unknown. Methods and Results: Patients referred for evaluation of left bundle branch block (LBBB)-type ventricular arrhythmia and suspected ARVD/C were prospectively evaluated by a standardized protocol including right ventricle (RV) cineangiography-guided myocardial biopsy. Sixteen patients had definite ARVD/C and four had probable ARVD/C. Three patients were found to have noncaseating granulomas on biopsy consistent with sarcoid. Age, systemic symptoms, findings on chest X-ray or magnetic resonance imaging (MRI), type of ventricular arrhythmia, RV function, ECG abnormalities, and the presence or duration of late potentials did not discriminate between sarcoid and ARVD/C. Left ventricular dysfunction (ejection fraction <50%) was present in 3/3 patients with cardiac sarcoid, but only 2/17 remaining patients with definite or probable ARVD/C (P = 0.01). Conclusions: In this prospective study of consecutive patients with suspected ARVD/C evaluated by a standard protocol including biopsy, the incidence of cardiac sarcoid was surprisingly high (15%). Clinical features, with the exception of left ventricular dysfunction and histological findings, did not discriminate between the two entities. [source] Tako-tsubo Cardiomyopathy Complicating Left Atrial Radiofrequency AblationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2007MICHAEL DERNTL M.D. Two female patients undergoing left atrial radiofrequency catheter ablation developed Tako-tsubo cardiomyopathy. This reversible form of left ventricular dysfunction is known to occur under conditions associated with marked sympathetic nervous activation. Radiofrequency catheter ablation in the left atrium can damage autonomic ganglionated plexi, leading to vagal withdrawal, thus resulting in enhanced sympathetic tone. Tako-tsubo cardiomyopathy has not been previously described following radiofrequency catheter ablation. [source] Obesity As a Risk Factor for Sustained Ventricular Tachyarrhythmias in MADIT II PatientsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2007GRZEGORZ PIETRASIK M.D. Background: Obesity, as defined by body mass index ,30 kg/m2, has been shown to be a risk factor for cardiovascular disease. However, data on the relationship between body mass index (BMI) and the risk of ventricular arrhythmias and sudden cardiac death are limited. The aim of this study was to evaluate the risk of ventricular tachyarrhythmias and sudden death by BMI in patients after myocardial infarction with severe left ventricular dysfunction. Methods: The risk of appropriate defibrillator therapy for ventricular tachycardia or ventricular fibrillation (VT/VF) by BMI status was analyzed in 476 nondiabetic patients with left ventricular dysfunction who received an implantable cardioverter defibrillator (ICD) in the Multicenter Automatic Defibrillator Implantation Trial-II (MADIT II). Results: Mean BMI was 27 ± 5 kg/m2. Obese patients comprised 25% of the study population. After 2 years of follow-up, the cumulative rates of appropriate ICD therapy for VT/VF were 39% in obese and 24% in nonobese patients, respectively (P = 0.014). In multivariate analysis, there was a significant 64% increase in the risk for appropriate ICD therapy among obese patients as compared with nonobese patients, which was attributed mainly to an 86% increase in the risk of appropriate ICD shocks (P = 0.006). Consistent with these results, the risk of the combined endpoint of appropriate VT/VF therapy or sudden cardiac death (SCD) was also significantly increased among obese patients (Hazard Ratio 1.59; P = 0.01). Conclusions: Our findings suggest that in nondiabetic patients with ischemic left ventricular dysfunction, a BMI ,30 kg/m2 is an independent risk factor for ventricular tachyarrhythmias. [source] Improved Survival of Cardiac Transplantation Candidates with Implantable Cardioverter Defibrillator Therapy:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2003Role of Beta-Blocker or Amiodarone Treatment Introduction: Survival in patients awaiting cardiac transplantation is poor due to the severity of left ventricular dysfunction and the susceptibility to ventricular arrhythmia. The potential role of implantable cardioverter defibrillators (ICDs) in this group of patients has been the subject of increasing interest. The aims of this study were to ascertain whether ICDs improve the survival rate of patients on the waiting list for cardiac transplantation and whether any improvement is independent of concomitant beta-blocker or amiodarone therapy. Methods and Results: Data comprised findings from 310 consecutive patients at a single center who were evaluated and deemed suitable for cardiac transplantation and placed on the waiting list. Kaplan-Meier actuarial approach was used for survival analysis. Survival analysis censored patients at time of transplantation or death. Of the 310 patients, 111 (35.8%) underwent successful cardiac transplantation and 164 (52.9%) died while waiting; 35 patients remain on the waiting list. Fifty-nine (19%) patients had ICD placement for ventricular arrhythmias prior to or after being listed. Twenty-nine (49.1%) ICD patients survived until cardiac transplantation, 13 (22%) patients died, and 17 (28.8%) remain on the waiting list. Among non-ICD patients, 82 (32.7%) received transplants, 151 (60.2%) died, and 18 (7.2%) remain on the waiting list. Survival rates at 6 months and 1, 2, 3, and 4 years were better for all ICD patients compared to non-ICD patients (log-rankx2, P = 0.0001). By multivariate analysis, ICD therapy and beta-blocker treatment were the strongest predictors of survival. Further, ICD treatment was associated with improved survival independent of concomitant treatment with beta-blocker or amiodarone. Among ICD and non-ICD patients treated with a beta-blocker or amiodarone, survivals at the 1 and 4 years were 93% vs 69% and 57% vs 32%, respectively (log-rankx2, P = 0.003). Conclusion: ICD therapy is associated with improved survival in high-risk cardiac transplant candidates, and ICD benefit appears to be independent of concomitant treatment. (J Cardiovasc Electrophysiol, Vol. 14, pp. 578-583, June 2003) [source] Endothelin System in Human Persistent and Paroxysmal Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2001BIANCA J.J.M. BRUNDEL Ph.D. Endothelin System in Atrial Fibrillation. Introduction: Activation of the endothelin system is an important compensatory mechanism that is activated during left ventricular dysfunction. Whether this system plays a role at the atrial level during atrial fibrillation (AF) has not been examined in detail. The purpose of this study was to investigate mRNA and protein expression levels of the endothelin system in AF patients with and without concomitant underlying valve disease. Methods and Results: Right atrial appendages of 36 patients with either paroxysmal or persistent AF were compared with 36 controls in sinus rhythm. The mRNA amounts of pro-endothelin-1 (pro-ET-1), endothelin receptor A (ET-A), and endothelin receptor B (ET-B) were studied by semiquantitative polymerase chain reaction. Protein amounts of the receptors were investigated by slot-blot analysis. mRNA amounts of pro-ET-1 were increased (+ 40%; P = 0.002) only in AF patients with underlying valve disease. ET-A and ET-B receptor protein amounts were significantly reduced in patients with paroxysmal AF (,39% and ,47%, respectively) and persistent AF with underlying valve disease (, 28% and , 30%, respectively) and in persistent AF without valve disease (,20% and ,40%, respectively). ET-A mRNA expression was unaltered in paroxysmal and persistent AF, whereas ET-B mRNA was reduced by 30% in persistent AF with (P < 0.001) or without (P = 0.04) valve disease, but unchanged in paroxysmal AF. Conclusion: Substantial changes in gene expression of the endothelin system were observed in human atria during AF, especially in the presence of underlying valve disease. Alterations in endothelin expression associated with AF could play a role in the pathophysiology of AF and the progression of underlying heart disease. [source] First Evidence of Premature Ventricular Complex-Induced Cardiomyopathy: A Potentially Reversible Cause of Heart FailureJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2000SUMEET S. CHUGH M.D. PVC-Induced Cardiomyopathy. Tachycardia-induced cardiomyopathy is a well-recognized and reversible condition, but left ventricular dysfunction due to frequent isolated premature ventricular complexes (PVCs) has not been reported. We observed resolution of dilated cardiomyopathy in a patient after a focal source of PVCs was eliminated by radiofrequency ablation. In a subset of patients with heart failure, PVC-induced cardiomyopathy may be a potentially reversible cause of left ventricular dysfunction. [source] N-terminal atrial natriuretic peptide and left ventricular geometry and function in a population sample of elderly malesJOURNAL OF INTERNAL MEDICINE, Issue 6 2000J. Ärnlöv Abstract. Ärnlöv J, Lind L, Stridsberg M, Andrén B, Lithell H (University of Uppsala, Sweden). N-terminal atrial natriuretic peptide and left ventricular geometry and function in a population sample of elderly males. J Intern Med 2000; 247: 699,708. Objectives. To investigate the relationships between N-terminal atrial natriuretic peptide (N-ANP) and left ventricular geometry and function. Design. A cross-sectional study of a population-based cohort. Setting. Follow-up of a health survey in Uppsala county, Sweden. Subjects., Two hundred and five men aged 70. Main outcome measures. A Delfia sandwich immunoassay was used to measure the plasma levels of N-ANP. M-mode and Doppler echocardiographic examinations were used to measure left ventricular dimensions, mass, geometry and systolic function and to classify the subjects into four groups (normal geometry, concentric remodelling, concentric hypertrophy or eccentric hypertrophy). Left ventricular systolic dysfunction was defined as a left ventricular ejection fraction , 0.40. Results. Plasma levels of N-ANP were significantly increased in subjects with left ventricular dysfunction compared to healthy subjects (702 ± 486, n = 14 vs. 277 ± 201 pmol L,1, n = 118, P < 0.0001), but there was a great overlap between the groups. N-ANP differed significantly between the four different left ventricular geometric groups (P = 0.02) with the highest N-ANP levels in the subjects with left ventricular eccentric hypertrophy (n = 40). However, N-ANP levels were no longer significantly associated with left ventricular geometry when taking the ejection fraction into account. Conclusions. This study showed that N-ANP levels were significantly elevated in subjects with left ventricular dysfunction, as well as in subjects with left ventricular hypertrophy. However, the increase in N-ANP seen in the eccentric hypertrophy group was mainly due to a decreased ejection fraction. [source] Aldosterone receptor antagonists , how cardiovascular actions may explain their beneficial effects in heart failureJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2010P. OVAERT Ovaert, P., Elliott, J., Bernay, F., Guillot, E., Bardon, T. Aldosterone receptor antagonists , how cardiovascular actions may explain their beneficial effects in heart failure. J. vet. Pharmacol. Therap.33, 109,117. Historically, aldosterone receptor antagonists (ARA) have been classified as ,potassium sparing diuretics'. However, the positive effect of spironolactone, the most extensively studied ARA, on morbidity and mortality observed in humans suffering cardiac insufficiency could not be explained by the renal effect of the drug alone, and a pivotal clinical study has led to extensive research. Many experimental studies have demonstrated that ARA have previously unexpected beneficial effects on the cardiovascular system including reduction in remodelling of the vascular smooth muscle cells and myocytes and improvement of endothelial cell dysfunction in heart failure. These effects improve vascular compliance and slow down the progression of left ventricular dysfunction and end-organ damage. Furthermore, aldosterone receptor blockade also restores the baroreceptor reflex, improving heart rate variability in heart failure in humans. Some of these effects have been demonstrated in dog models of cardiac disease and so justified further investigation of the potential benefit of ARA in dogs with congestive heart failure (CHF). Positive effects of spironolactone on morbidity and mortality appear to have been seen in studies conducted in dogs suffering from naturally occurring CHF. In addition, eplerenone has been shown to have benefits in canine models of heart failure. The precise mechanisms by which ARA produce these beneficial effects in dogs remain to be determined but this group of drugs clearly provide therapeutic actions out-with their diuretic effects. [source] The Effects of Rate-Adaptive Atrial Pacing Versus Ventricular Backup Pacing on Exercise Capacity in Patients with Left Ventricular DysfunctionPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2009M.S.C.E., ROD PASSMAN M.D. Background: Atrial rate-adaptive pacing may improve cardiopulmonary reserve in patients with left ventricular dysfunction. Methods: A randomized, blinded, single-crossover design enrolled dual-chamber implantable defibrillator recipients without pacing indications and an ejection fraction ,40% to undergo cardiopulmonary exercise treadmill stress testing in both atrial rate-adaptive pacing (AAIR) and ventricular demand pacing (VVI) pacing modes. The primary endpoint was change in peak oxygen consumption (VO2). Secondary endpoints were changes in anaerobic threshold, perceived exertion, exercise duration, and peak blood pressure. Results: Ten patients, nine males, eight with New York Heart Association class I, mean ejection fraction 24 ± 7%, were analyzed. Baseline VO2 was 3.6 ± 0.5 mL/kg/min. Heart rate at peak exercise was significantly higher during AAIR versus VVI pacing (142 ± 18 vs 130 ± 23 bpm; P = 0.05). However, there was no difference in peak VO2 (AAIR 23.7 ± 6.1 vs VVI 23.8 ± 6.3 mL/kg/min; P = 0.8), anaerobic threshold (AAIR 1.3 ± 0.3 vs VVI 1.2 ± 0.2 L/min; P = 0.11), rate of perceived exertion (AAIR 7.3 ± 1.5 vs VVI 7.8 ± 1.2; P = 0.46), exercise duration (AAIR 15 minutes, 46 seconds ± 2 minutes, 54 seconds vs VVI 16 minutes, 3 seconds ± 2 minutes, 48 seconds; P = 0.38), or peak systolic blood pressure (AAIR 155 ± 22 vs VVI 153 ± 21; P = 0.61) between the two pacing modes. Conclusion: In this study, AAIR pacing did not improve peak VO2, anaerobic threshold, rate of perceived exertion, or exercise duration compared to VVI backup pacing in patients with left ventricular dysfunction and no pacing indications. [source] Performance of Phonoelectrocardiographic Left Ventricular Systolic Time Intervals and B-Type Natriuretic Peptide Levels in the Diagnosis of Left Ventricular DysfunctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2007Brian Moyers M.D. Background: Systolic time intervals measured by echocardiography and carotid artery tracings are validated methods of assessing left ventricular function. However, the clinical utility of phonoelectrocardiographic systolic time intervals for predicting heart failure using newer technology has not been evaluated. Methods: We enrolled 100 adult patients undergoing left heart catheterization. Participants underwent computerized phonoelectrocardiographic analysis, left ventricular end-diastolic pressure (LVEDP) measurement, transthoracic echocardiographic measurement of left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP) testing. The heart rate-adjusted systolic time intervals included the time from the Q wave onset to peak S1 (electromechanical activation time, EMAT), Q wave onset to peak S2 (electromechanical systole, Q-S2), and peak S1 to peak S2 (left ventricular systolic time, LVST). Left ventricular dysfunction was defined as the presence of both LVEDP >15 mmHg and LVEF <50%. Results: EMAT (r =,0.51; P < 0.0001), EMAT/LVST (r =,0.41; P = 0.0001), and Q-S2 (r =,0.39; P = 0.0003) correlated with LVEF, but not with LVEDP. An abnormal EMAT ,15 (odds ratio 1.38, P < 0.0001) and EMAT/LVST ,0.40 (OR 1.13, P = 0.002) were associated with left ventricular dysfunction. EMAT ,15 had 44% sensitivity, 94% specificity, and a 7.0 likelihood ratio for left ventricular dysfunction, while EMAT/LVST ,0.40 had 55% sensitivity, 95% specificity, and a 11.7 likelihood ratio. In patients with an intermediate BNP (100,500 pg/mL), the likelihood ratio increased from 1.1 using the BNP result alone to 11.0 when adding a positive EMAT test for predicting left ventricular dysfunction. Conclusions: Phonoelectrocardiographic measures of systolic time intervals are insensitive but highly specific tests for detecting abnormalities in objective markers of left ventricular function. EMAT and EMAT/LVST provide diagnostic information independent of BNP for detecting patients with left ventricular dysfunction. [source] Usefulness of Risk Stratification for Future Cardiac Events in Infarct Survivors with Severely Depressed Versus Near-Normal Left Ventricular Function: Results From a Prospective Long-Term Follow-Up StudyANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2003Thomas Klingenheben Background: Although primary preventive therapy with implantable cardioverter defibrillators has recently been shown to be effective in patients with coronary artery disease and left ventricular dysfunction, further identification of patients at particularly high risk for arrhythmic death would improve the cost effectiveness of device therapy. The value of risk stratification in postinfarction patients with versus those without left ventricular dysfunction has not been investigated in detail in infarct survivors treated according to contemporary therapeutic guidelines. Methods: Patients with acute myocardial infarction underwent coronary angiography including left ventricular angiography in an attempt to restore antegrade flow of the infarct-related artery. Additionally, patients underwent noninvasive autonomic risk stratification by means of heart rate variability (HRV) and baroreflex sensitivity (BRS) measurements prior to hospital discharge. Results: A total of 411 patients were prospectively included in the study. The primary study endpoint of cardiac death and arrhythmic events was significantly more common in patients with LVEF , 35% as compared to those with preserved LV function (27% vs 4%; P < 0.0001). In patients with LV dysfunction, HRV and BRS were significant risk predictors on univariate (P < 0.01 for BRS; P = 0.04 for HRV) and multivariate (P = 0.028 for BRS; P = 0.053 for HRV) analyses. In contrast, in patients with preserved LV function, only patency of the infarct artery but not autonomic markers was significantly predictive of cardiac death and arrhythmic events. Conclusion: The present study demonstrates that autonomic testing does not yield predictive power in infarct survivors with preserved left ventricular function. Accordingly, cost effectiveness of risk stratification and subsequent preventive therapy may be improved by restricting risk stratification to patients with impaired LV function. [source] Cardioprotection from ischemia-reperfusion injury due to Ras-GTPase inhibition is attenuated by glibenclamide in the globally ischemic heartCELL BIOCHEMISTRY AND FUNCTION, Issue 4 2007Ibrahim Al-Rashdan Abstract The present study was designed to see if acute local inhibition of Ras-GTPase before or after ischemia (during perfusion) would produce protection against ischemia and reperfusion (I/R)-induced cardiac dysfunction. The effect of glibenclamide, an inhibitor of cardiac mitochondrial ATP-sensitive potassium (mitoKATP) channels, on Ras-GTPase-mediated cardioprotection was also studied. A 40,min episode of global ischemia followed by a 30,min reperfusion in perfused rat hearts produced significantly impaired cardiac function, measured as left ventricular developed pressure (Pmax) and left ventricular end-diastolic pressure (LVEDP). Perfusion with Ras-GTPase inhibitor FPT III before I/R [FPT(pre)], significantly enhanced cardiac recovery in terms of left ventricular contractility. Pmax was significantly higher at the end of 30,min reperfusion in FPT(pre)-treated hearts compared to pre-conditioned hearts. However, the degree of improvement in left ventricular contractility was significantly less when FPT III was given only after ischemia during reperfusion [FPT(post)]. Combination treatment with FPT III and glibenclamide before I/R resulted in significant reduction of FPT III-mediated cardioprotection. These data suggest that activation of Ras-GTPase signaling pathways during ischemia are critical in the development of left ventricular dysfunction and that opening of mitoKATP channels, at least in part, contributes to cardioprotection produced by Ras-GTPase inhibition. Copyright © 2006 John Wiley & Sons, Ltd. [source] Disturbed glucose metabolism is associated with left ventricular dysfunction using tissue Doppler imaging in patients with myocardial infarctionCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2007Loghman Henareh Summary Aims:, To investigate the association between glucose abnormalities and left ventricular (LV) function assessed by tissue Doppler imaging (TDI) in patients with previous history of myocardial infarction and without known diabetes mellitus. Patients and methods:, In a cross-sectional study, 123 patients, aged 31,80 years, with a history of previous myocardial infarction and without known diabetes mellitus were examined with TDI echocardiography. A standard oral glucose test (OGTT) with 75 g of glucose was performed. Results:, Two-hour plasma glucose were significantly and negatively associated with TDI parameters such as LV ejection time; early diastolic filling velocity (E,- v); ratio of the early to late diastolic filling velocity (E,/A,) and positively associated with regional myocardial performance index (MPI) (P<0·05). Left ventricular ejection time and MPI were significantly higher; E,/A, and E,- v were significantly lower in patients with disturbed glucose metabolism compared with patients with normal glucose tolerance (P<0·01). These differences remain significant also when the patients with DM were excluded. Conclusions:, The present study demonstrates that disturbed glucose metabolism is associated with more pronounced LV dysfunction using TDI in patients with myocardial infarction. These abnormalities in LV function were more common not only in subjects with diabetes, but also in patients with prediabetic condition, impaired glucose intolerance. [source] | |||||||||||||||||||||||||