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

Background 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. Objectives 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. Methods and results 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 12 421 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. Conclusions 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.

Automated summary

This study found that predictors of renin-angiotensin system inhibitors/angiotensin receptor neprilysin inhibitors (RASI/ARNI) and beta-blockers use in heart failure patients include hypertension, younger age, outpatient care, and specialty treatment. The use of these medications was associated with lower risk of cardiovascular mortality/hospitalization and all-cause mortality in a matched cohort. Positive control analysis confirmed these findings, and there were no associations with the negative control outcome.