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There are limited data on the prognostic implications of brain natriuretic peptide (BNP) assessment in patients with mildly symptomatic heart failure (HF) who receive cardiac resynchronization therapy with a defibrillator (CRT-D).The effect of elevated baseline and 1-year BNP levels (dichotomized at the upper tertile BNP of 120 pg/mL) on the risk of HF or death was assessed among the cohort of 1197 patients with baseline BNP data enrolled in MADIT (Multicenter Automated Defibrillator Implantation Trial)-CRT. Elevated baseline BNP was associated with a significant 68% (P=0.007) and 58% (P=0.02) increase in the risk of HF or death among MADIT-CRT patients allocated to CRT-D and implantable cardioverter defibrillator-only therapy, respectively. At 1 year of follow-up, patients allocated to CRT-D displayed significantly greater reductions in BNP (26% reduction) levels compared with implantable cardioverter defibrillator-only patients (8% increase; P=0.005). Patients with CRT-D in whom 1-year BNP levels were reduced or remained low experienced a significantly lower risk of subsequent HF or death as compared with patients in whom 1-year BNP levels were high. Similarly, the echocardiographic response to CRT-D was highest among those who maintained low BNP levels or in whom BNP level at 1-year was reduced.Our findings suggest that assessment of baseline and follow-up BNP provides important prognostic implications in patients with mildly symptomatic HF who receive CRT.URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271. [ABSTRACT FROM AUTHOR]

Right ventricular function (RVF) is an important determinant of outcome in patients with heart failure, and those with severe RV dysfunction have worse outcome after cardiac resynchronization therapy (CRT). We used data from the Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT) Trial to determine whether therapy with CRT is influenced by or affects RV function and to define the relationship between RV function and outcomes.A total of 1820 patients were randomly assigned to CRT plus implantable cardioverter defibrillator or implantable cardioverter defibrillator-only in a 3:2 ratio. We assessed RVF as RV fractional area change by echocardiography at baseline and after 1 year of therapy (n=1511 and 1273, respectively). The median RV fractional area change was 41%, with 10.9% of patients <35% at baseline. Baseline RVF did not modify the treatment effect of CRT on the primary outcome (interaction P=0.19). Randomization to CRT-implantable cardioverter defibrillator was associated with a greater improvement in RVF (ΔRV fractional area change 8.1% versus 5.4%; P<0.001), and improvement in RVF was related to subsequent outcomes. Every 5-point increase in RV fractional area change was associated with a 22% reduction in event rates (hazard ratio, 0.78; 95% confidence interval, 0.66-0.92; P=0.003), although this was not independent of the concurrent improvement in left ventricular function. Baseline tricuspid regurgitant velocity, a measure of pulmonary systolic pressure, was predictive of events in a multivariate analysis (hazard ratio, 1.86; 95% confidence interval, 1.24-2.8; P=0.003).In this population with mild heart failure symptoms, CRT was associated with improvement in RVF, which improved in parallel with improvement in left ventricular function. Patients with the best RVF at 1 year demonstrated the lowest subsequent event rates.URL: http://www.clinicaltrials.gov. Unique identifier: NCT01294449. [ABSTRACT FROM AUTHOR]

The article presents information study which investigated on the benefits of cardiac resynchronization therapy (CRT) and the type of heart failure patients who would benefit most. Both mechanical dyssynchrony and contractile function can reportedly help determine which patients may respond positively to and gain benefits from CRT. Generally, patients with mild to moderate case of dysynchrony or with best contractile function at baseline are the ones who would benefit from CRT.

Background: Coronary revascularization (CR) may confer electrical stability in patients with ischemic cardiomyopathy. However, data regarding the effect of CR on the development of ventricular tachyarrhythmias in this population are limited. Objective: The purpose of this study was to evaluate the association between CR and arrhythmic risk in postmyocardial infarction (post-MI) patients with left ventricular dysfunction. Methods: The risk for life-threatening ventricular tachyarrhythmias (defined as a first appropriate defibrillator therapy for ventricular tachycardia [VT]/ventricular fibrillation [VF] or death) was compared between post-MI patients with and those without prior CR (n = 612 and 147, respectively) enrolled in the Multicenter Automatic Defibrillator Implantation Trial–Cardiac Resynchronization Therapy (MADIT-CRT). Results: The 3-year cumulative rate of VT/VF or death was significantly higher among patients without prior CR (42%) than in patients who underwent prior CR (32%, P = .02). Multivariate analysis demonstrated that patients without prior CR had 48% increased risk (P = .01) for VT/VF or death. Risk reduction associated with CR was related to elapsed time from CR, assessed both as a categorical variable (tertiles for time from CR: ≥7 years, hazard ratio [HR] = 1.93, P = .001; 1.5–7 years, HR = 1.70, P = .01 vs <1.5 years) and as a continuous measure (4%, P = .002, increased risk for VT/VF or death per 1-year increment of elapsed time from CR). The effect of CR on arrhythmic risk was similar in patients treated with a defibrillator alone or when combined with cardiac resynchronization therapy. Conclusion: Post-MI patients with left ventricular dysfunction who undergo CR experience a time-dependent reduction in the risk for subsequent life-threatening ventricular tachyarrhythmias. [ABSTRACT FROM AUTHOR]

Background: Data on long-term follow-up and factors influencing mortality in implantable cardioverter-defibrillator (ICD) recipients are limited. Objective: The aim of this study was to evaluate mortality during long-term follow-up and the predictive value of several risk markers in the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II) patients with implanted cardioverter-defibrillators (ICDs). Methods: The study involved U.S. patients from the MADIT II trial randomized to and receiving ICD treatment. Data regarding long-term mortality were retrieved from the National Death Registry. Several clinical, biochemical, and electrocardiogram variables were tested in a multivariate Cox model for predicting long-term mortality, and a score identifying high-, medium-, and lower risk patients was developed. Results: The study population consisted of 655 patients, mean age 64 ± 10 years. During a follow-up of up to 9 years, averaging 63 months, 294 deaths occurred. The 6-year cumulative probability of death was 40%, with evidence of a constant risk of about 8.5% per year among survivors. Median survival was estimated at 8 years. Multivariate analysis identified age >65 years, New York Heart Association class 3–4, diabetes, non–sinus rhythm, and increased levels of blood urea nitrogen as independent risk predictors of mortality. Patients with three or more of these risk factors were characterized by a 6-year mortality rate of 68%, compared with 43% in those with one to two risk factors and 19% in patients with no risk factors. Conclusion: A combination of a few readily available clinical variables indicating advanced disease and comorbid conditions identifies ICD patients at high risk of mortality during long-term follow-up. [Copyright &y& Elsevier]

Background: Much of prognostic implications of ventricular arrhythmia storms remain unclear.Objective: We evaluated the risk associated with electrical storm in patients with defibrillators in the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) study.Methods: Electrical storm was defined as > or =3 episodes of ventricular tachycardia (VT) or ventricular fibrillation (VF) in 24 hours.Results: Of the 719 patients who received internal cardiac defibrillator (ICD) implants and had follow-up in the MADIT-II, 27 patients (4%) had electrical storm, 142 (20%) had isolated episodes of VT/VF, and the remaining 550 patients had no ICD-recorded VT events. Baseline clinical characteristics among the groups were similar. Patients who experienced electrical storm had a significantly higher risk of death. After adjustments for relevant clinical covariates, the hazard ratio (HR) for death in the first 3 months after the storm event was 17.8 (95% confidence interval [CI] 8.0 to 39.5, P <.01) in comparison with those with no VT/VF. This risk continued even after 3 months for those with electrical storm (HR of 3.5, 95% CI 1.2 to 9.8, P = .02). Study patients with isolated VT/VF episodes also were at an increased risk of dying (HR = 2.5, 95% CI 1.5 to 4.0, P <.01) when compared with patients without VT/VF episodes. Statistically significant predictors of electrical storm were interim postenrollment coronary events (myocardial infarction or angina) HR 3.1 (95% CI 1.2 to 8.1, P = .02) and isolated VT or VF HR 9.2 (95% CI 4.0 to 20.9, P <.01).Conclusion: Postinfarction patients with severe left ventricular dysfunction in whom electrical storm developed have significantly higher mortality than patients with only isolated VT/VF as well as those without any episodes of VT/VF. Patients who experienced postenrollment ventricular arrhythmias and/or interim coronary events during follow-up were at higher risk for VT/VF storms. [ABSTRACT FROM AUTHOR]