Prognostic Implication of Heart Failure With Reduced and Midrange Ejection Fraction in Adults With Congenital Heart Disease.

BACKGROUND: In the acquired heart disease population, heart failure (HF) is broadly classified based on left ventricular (LV) ejection fraction (EF) as HF with reduced EF (HFrEF), HF with midrange EF (HFmrEF), and HF with preserved EF (HFpEF). The prognostic role of this LVEF-based HF classification has not been evaluated in the adult congenital heart disease (CHD) population because of anatomic and physiological heterogeneity within this population. The current study aimed to address this knowledge gap, by assessing the prevalence, predictors (correlates), and prognostic implications of HFrEF in adults with CHD. METHODS: This is a retrospective cohort study of adults with CHD and morphologic LV as the systemic ventricle. Patients were classified as HFrEF (LVEF ≤40%), HFmrEF (LVEF 41%-49%), and pEF (LVEF ≥50%). RESULTS: Of 7981 patients, 7203 (90%) had pEF, 451 (6%) had HFmrEF, and 327 (4%) had HFrEF. The correlates of HFrEF were older age, male sex, pacemaker implantation, multiple prior sternotomies, and acquired comorbidities such as hypertension, coronary artery disease, diabetes, and atrial fibrillation. The 15-year mortality risk was 18%, 36%, and 67% in the pEF, HFmrEF, and HFrEF groups, respectively (P < 0.001). Both HFmrEF (adjusted hazard ratio: 1.64 [95% confidence interval: 1.29; 2.09], P < 0.001) and HFrEF (adjusted hazard ratio: 3.33 [95% confidence interval: 2.72; 4.27], P < 0.001) were associated with mortality on multivariable analysis. CONCLUSIONS: Given the elevated risk of mortality in patients with LV systolic dysfunction (both mrEF and rEF) and the emerging data suggesting the efficacy of HF therapy in patients with CHD, there is an urgent need to implement HF therapy in this population.