Prevalence and Prognostic Implications of Left Ventricular Systolic Dysfunction in Adults With Congenital Heart Disease

Background: Although the prevalence and prognostic implications of left ventricular systolic dysfunction (LVSD), and the effect of cardiac therapies on LVSD are well described in patients with acquired heart disease, such data are sparse in adults with congenital heart disease (CHD). Objectives: The purpose of this study was to determine the prevalence, risk factors, and prognostic implications of LVSD, and the effect of cardiac therapies (guideline-directed medical therapy [GDMT] and cardiac resynchronization therapy [CRT]) on LVSD in adults with CHD. Methods: This was a retrospective study of adults with CHD with systemic LV (2003-2019). LVSD was defined as left ventricular ejection fraction (LVEF) <52%/<54% (men/women). Cardiovascular event was defined as heart failure hospitalization, heart transplant, and cardiovascular death. Results: Of 4,358 patients, 554 (12%) had LVSD, and the prevalence of LVSD was higher in right-sided lesions compared with left-sided lesions (15% vs 10%; P < 0.001). Cardiovascular events occurred in 312 (7%) patients. LVEF was independently associated with cardiovascular events (HR: 0.95; 95% CI: 0.93-0.97; P = 0.009). Of 544 patients with LVSD, 311 received GDMT and 48 patients received CRT. LVEF increased by 6% (95% CI: 2%-10%) and 11% (95% CI: 8%-14%), and N-terminal pro-hormone brain natriuretic peptide decreased by 151 pg/mL (95% CI: 62-289 pg/mL) and 201 pg/mL (95% CI: 119-321 pg/mL) in patients who received GDMT and CRT, respectively. Conclusions: LVSD was present in 12% of adults with CHD, was more common in patients with right-sided lesions, and was associated with cardiovascular events. GDMT and CRT were associated with improvement in LVEF. These results provide a foundation for clinical trials to rigorously test the benefits of these therapies in CHD patients.