Heart Failure Therapy Improves Outcomes in Adults With Congenital Heart Disease and Left Ventricular Dysfunction

BACKGROUND: There are limited data about the role of guideline-directed medical therapy (GDMT) in adults with congenital heart disease presenting with heart failure with reduced ejection fraction. OBJECTIVES: This study aimed to assess the effect of GDMT on cardiac function, congestion, and mortality in adults with congenital heart disease presenting with heart failure with reduced ejection fraction. We hypothesized that GDMT uptitration was associated with improved cardiac function, less congestion, and lower mortality. METHODS: GDMT score, left ventricular ejection fraction (LVEF), and N-terminal pro-b-type brain natriuretic peptide (NT-proBNP) levels were assessed at baseline encounter (baseline GDMT score) and 1-year follow-up. Delta (Δ) GDMT was calculated as GDMT at 1 year minus GDMT at baseline. GDMT uptitration was defined as ΔGDMT score > 0. RESULTS: Of 327 patients (age 46 ± 16 years; LVEF 31 ± 6%), the baseline GDMT score was 2 (1,3), and 135 (41%) had GDMT uptitration. Although patients with GDMT uptitration had similar LVEF and NT-proBNP levels at baseline encounter compared to patients without GDMT uptitration, the GDMT uptitration group had greater temporal improvement in LVEF (relative ΔLVEF 32 ± 12% vs 15 ± 7%; P < 0.001), reduction in NT-proBNP levels (relative ΔNT-proBNP -39 ± 15% vs -21 ± 19%; P < 0.001), and a lower 10-year incidence of death/transplant (38% vs 59%; P = 0.002). Higher ΔGDMT score (adjusted HR: 0.68 [95% CI: 0.54-0.83]; P < 0.001) and ΔLVEF (adjusted HR: 0.79 [95% CI: 0.65-0.96], P = 0.002) were associated with a lower risk of death/transplant. CONCLUSIONS: GDMT uptitration was associated with improved cardiac function, less congestion, and a lower incidence of death/transplant. Overall GDMT score was low, and only 41% of patients had GDMT uptitration, suggesting suboptimal therapy and need for optimization of heart failure therapy in this population.