Heart failure pharmacological treatments and outcomes in heart failure with mildly reduced ejection fraction.

Abstract

Guideline recommendations for the treatment of heart failure with mildly reduced ejection fraction (HFmrEF) derive from small subgroups in post-hoc analyses of randomized trials. We investigated predictors of renin-angiotensin system inhibitors/angiotensin receptor neprilysin inhibitors (RASI/ARNI) and beta-blockers use, and the associations between these medications and mortality/morbidity in a large real-world cohort with HFmrEF. Patients with HFmrEF (EF 40-49%) from the Swedish HF Registry were included. The associations between medications and cardiovascular (CV) mortality/HF hospitalization (HFH), and all-cause mortality were assessed through Cox regressions in a 1:1 propensity score-matched cohort. A positive control analysis was performed in patients with EF<40%, while a negative control outcome analysis had cancer-related hospitalization as endpoint. Of 12421 patients with HFmrEF, 84% received RASI/ARNI and 88% beta-blockers. Shared-independent predictors of RASI/ARNI and beta-blockers use were younger age, being an outpatient, follow-up in specialty care, and hypertension. In the matched cohorts, use of both RASI/ARNI and beta-blocker use was separately associated with lower risk of CV mortality/HFH [hazard ratio (HR)=0.90, 95% confidence interval (CI): 0.83-0.98 and HR=0.82, 95% CI: 0.74-0.90, respectively] and of all-cause mortality (HR=0.75, 95% CI: 0.69-0.81 and HR=0.79, 95% CI: 0.72-0.87, respectively). Results were consistent at the positive control analysis, and there were no associations between treatment use and the negative control outcome. RASI/ARNI and beta-blockers were extensively used in this large real-world cohort with HFmrEF. Their use was safe since associated with lower mortality and morbidity. Our findings confirm the real-world evidence from previous post-hoc analyses of trials, and represent a further call for implementing guideline recommendations.