Prognostic Implication of Heart Failure with Reduced and Mid-range Ejection Fraction in Adults with Congenital Heart Disease

ABSTRACT 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 mid-range 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 physiologic heterogeneity within this population. The current study aimed to address this knowledge gap, by asssessing the prevalence, predictors (correlates), and prognostic implications of HFrEF in adults with CHD. Methods 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 7,981 patients, 7,203 (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 pEF, HFmrEF, and HFrEF groups, respectively (p<0.001). Both HFmrEF (adjusted HR 1.64, [95%CI 1.29; 2.09], p<0.001), and HFrEF (adjusted HR 3.33, [95%CI 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 efficacy of HF therapy in patients with CHD, there is an urgent need to implement HF therapy in this population.