Non-ischaemic cardiomyopathy, sudden death and implantable defibrillators: a review and meta-analysis

The angiotensin-receptor-neprilysin inhibitor (ARNI) LCZ696 reduced cardiovascular deaths and all-cause mortality compared with enalapril in patients with chronic heart failure in the prospective comparison of ARNI with an Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial. To more completely understand the components of this mortality benefit, we examined the effect of LCZ696 on mode of death.

The purpose of this multicenter randomized trial was to compare total mortality during therapy with amiodarone or an implantable cardioverter-defibrillator (ICD) in patients with nonischemic dilated cardiomyopathy (NIDCM) and nonsustained ventricular tachycardia (NSVT). Whether an ICD reduces mortality more than amiodarone in patients with NIDCM and NSVT is unknown. One hundred three patients with NIDCM, left ventricular ejection fraction < or =0.35, and asymptomatic NSVT were randomized to receive either amiodarone or an ICD. The primary end point was total mortality. Secondary end points included arrhythmia-free survival, quality of life, and costs. The study was stopped when the prospective stopping rule for futility was reached. The percent of patients surviving at one year (90% vs. 96%) and three years (88% vs. 87%) in the amiodarone and ICD groups, respectively, were not statistically different (p = 0.8). Quality of life was also similar with each therapy (p = NS). There was a trend with amiodarone, as compared to the ICD, towards improved arrhythmia-free survival (p = 0.1) and lower costs during the first year of therapy ($8,879 US dollars vs. $22,039 US dollars, p = 0.1). Mortality and quality of life in patients with NIDCM and NSVT treated with amiodarone or an ICD are not statistically different. There is a trend towards a more beneficial cost profile and improved arrhythmia-free survival with amiodarone therapy.

Patients with heart failure are at increased risk of sudden death and death attributed to progressive pump failure. We assessed the effect of candesartan on cause-specific mortality in patients enrolled in the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM) program. The CHARM program consisted of 3 component trials that enrolled patients with symptomatic heart failure: CHARM-Alternative (n=2028; LVEF 40%). Patients were randomized to candesartan, titrated to 32 mg QD, or placebo and were followed up for a median of 37.7 months. All deaths were reviewed by a blinded adjudication committee and categorized according to prespecified definitions on the basis of a narrative and source documentation. The number and rate of deaths by cause were calculated for each of the component trials and the overall program. Of all the patients, 8.5% died suddenly, and 6.2% died of progressive heart failure. Candesartan reduced both sudden death (HR 0.85 [0.73 to 0.99], P=0.036) and death from worsening heart failure (HR 0.78 [0.65 to 0.94], P=0.008). These reductions were most apparent in the patients with LVEF<=40% [corrected]. Candesartan reduced sudden death and death from worsening heart failure in patients with symptomatic heart failure, although this reduction was most apparent in patients with systolic dysfunction.