Adults with repaired systemic biventricular congenital heart disease with a systemic left ventricle and heart failure with reduce ejection fraction.

BACKGROUND

Results of observational studies assessing clinical benefits of guideline-directed medical therapy (GDMT) for heart failure (HF) in adults with congenital heart disease are conflicting. This is because these studies were based on a heterogenous population and lacked standardized criteria for assessing adequacy of HF therapy across studies. The current study addressed these limitations by studying the effect of GDMT (using a standardized GDMT score) in adults with repaired systemic biventricular congenital heart disease, systemic left ventricle, and HF with reduced ejection fraction.

METHODS

HF with reduced ejection fraction was defined as stage B/C HF and systemic left ventricular EF < 50%. GDMT score was assessed at baseline encounter (baseline GDMT score) and 1-year follow-up. GDMT uptitration was calculated as defined as ∆GDMT (∆=delta or change in) score from baseline. Cox regression was used to assess the relationship between HF therapy (baseline and ∆GDMT score) and outcomes (HF hospitalization and mortality).

RESULTS

Of 778 patients, baseline and ∆GDMT scores were 2 (1, 3) and 0.56 (0.49, 0.62), respectively. Of 778, only 258 (33%) had GDMT uptitration (∆GDMT score >0). Higher use of GDMT at baseline (adjusted hazard ratio [HR] per 1 point increase in GDMT score 0.83, 95% confidence interval [CI] 0.74, 0.92, P < .001), and increased use of GDMT over time (adjusted HR for 1 point increase in ∆GDMT score HR 0.71, 95% CI 0.62, 0.82, P < .001) were associated with lower risk of HF hospitalization. Higher baseline GDMT score (adjusted HR 0.87, 95% CI 0.76, 0.98, P = .01), and ∆GDMT score (adjusted HR 0.84, 95% CI 0.72, 0.86, P = .002) were also associated with lower mortality.

CONCLUSIONS

GDMT use at baseline, and GDMT uptitration were associated with improved outcomes and suggest a dose-dependent relationship between use of GDMT and risk of adverse outcomes. Furthermore, 67% of patients did not receive GDMT uptitration, suggesting suboptimal therapy and opportunities for improvement.