Effect of sacubitril/valsartan on investigator-reported ventricular arrhythmias in PARADIGM-HF

Aims: Sudden death is a leading cause of mortality in heart failure with reduced ejection fraction (HFrEF). In PARADIGM-HF, sacubitril/valsartan reduced the incidence of sudden death. The purpose of this post hoc study was to analyse the effect of sacubitril/valsartan, compared to enalapril, on the incidence of ventricular arrhythmias. Methods and results: Adverse event reports related to ventricular arrhythmias were examined in PARADIGM-HF. The effect of randomized treatment on two arrhythmia outcomes was analysed: ventricular arrhythmias and the composite of a ventricular arrhythmia, implantable cardioverter defibrillator (ICD) shock or resuscitated cardiac arrest. The risk of death related to a ventricular arrhythmia was examined in time-updated models. The interaction between heart failure aetiology, or baseline ICD/cardiac resynchronization therapy-defibrillator (CRT-D) use, and the effect of sacubitril/valsartan was analysed. Of the 8399 participants, 333 (4.0%) reported a ventricular arrhythmia and 372 (4.4%) the composite arrhythmia outcome. Ventricular arrhythmias were associated with higher mortality. Compared with enalapril, sacubitril/valsartan reduced the risk of a ventricular arrhythmia (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.62-0.95; p = 0.015) and the composite arrhythmia outcome (HR 0.79, 95% CI 0.65-0.97; p = 0.025). The treatment effect was maintained after adjustment and accounting for the competing risk of death. Baseline ICD/CRT-D use did not modify the effect of sacubitril/valsartan, but aetiology did: HR in patients with an ischaemic aetiology 0.93 (95% CI 0.71-1.21) versus 0.53 (95% CI 0.37-0.78) in those without an ischaemic aetiology (p for interaction = 0.020). Conclusions: Sacubitril/valsartan reduced the incidence of investigator-reported ventricular arrhythmias in patients with HFrEF. This effect may have been greater in patients with a non-ischaemic aetiology.