Sacubitril/Valsartan and Sudden Cardiac Death According to Implantable Cardioverter-Defibrillator Use and Heart Failure Cause: A PARADIGM-HF Analysis

Objectives: The purpose of this study was to investigate the effect of sacubitril/valsartan therapy on sudden cardiac death (SCD) according to the use of and eligibility for an implantable cardioverter-defibrillator (ICD), stratified by heart failure cause.

Background: SCD still accounts for a significant proportion of overall mortality in heart failure with reduced ejection fraction (HFrEF).

Methods: Patients enrolled in the PARADIGM-HF (Prospective Comparison of ARNI with an ACE-Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure) trial (n = 8,399) were evaluated to assess patterns of ICD implantation and eligibility according to clinical guidelines. The impact of ICD (adjusted for propensity of ICD implantation) and sacubitril/valsartan therapy on SCD was evaluated by using cause-specific Cox models and competing risk analysis.

Results: At baseline, of the 7,145 patients (85%) eligible for ICD implantation, only 1,243 (15%) had an ICD. Use of ICD varied by region with the highest rates in North America (56%) and lowest in Asia-Pacific (1.7%). In a propensity score-adjusted analysis, use of an ICD was associated with a 56% lower risk of SCD in ICD-eligible patients, in both patients with ischemic (p < 0.001) and nonischemic cardiomyopathy (p = 0.02). Sacubitril/valsartan reduced SCD risk in patients with an ICD (hazard ratio [HR]: 0.49; 95% confidence interval [CI]: 0.25 to 0.99) and in those who were eligible for but did not receive an ICD (HR: 0.81; 95% CI: 0.67 to 0.98). This effect was particularly evident in nonischemic cardiomyopathy (p < 0.05), although interaction with the cause of HF was not significant (p = 0.11 in subjects using an ICD and p = 0.25 in eligible nonusers).

Conclusions: Use of an ICD was associated with lower rates of SCD, regardless of HF cause but was underused in most regions of the world in the PARADIGM-HF study. Sacubitril/valsartan reduced SCD risk regardless of use of an ICD or eligibility, particularly in ICD users and nonischemic cardiomyopathy.