Determinants of Guideline-Directed Medical Therapy Implementation During Heart Failure Hospitalization.

Background: Despite evidence that guideline-directed medical therapies (GDMTs) improve outcomes in patients with heart failure (HF) with reduced ejection fraction (HFrEF), implementation remains suboptimal. Objectives: The purpose of this study was to measure GDMT implementation during acute HFrEF hospitalization, evaluate the association between socioeconomic factors and GDMT implementation, and assess the association of GDMT utilization with subsequent clinical events. Methods: Retrospective determination of GDMT utilization using a modified optimal medical therapy (mOMT) score (which accounts for specific contraindications to drugs) during unplanned HF hospitalization of consecutive adult patients with new-onset or previously diagnosed HFrEF from 2017 to 2018. Outcomes included discharge mOMT score, association between socioeconomic factors and GDMT implementation (assessed using both the Mann-Whitney U test for binary variables and the Kruskall-Wallace for nonbinary variables), composite outcome 1-year all-cause mortality and 1-year HF readmission, and each component as a function of discharge mOMT score (assessed using univariate and multivariable Cox proportional hazards regression models). Results: Of 391 patients fulfilling entry criteria (of which 152 [38.9%] had new-onset HFrEF), only 49 (12.5%) had a perfect or near-perfect discharge mOMT score. Black patients and those experiencing homelessness had significantly lower discharge mOMT scores. Higher discharge mOMT score is associated with a lower rate of composite endpoint events, particularly in patients with new-onset HFrEF. Overall, a 0.1-increase in the mOMT score resulted in a 9.2% reduction in the composite endpoint. Conclusions: Suboptimal implementation of GDMT during HF hospitalization is widespread and is associated with a worse outcome. Black patients and patients experiencing homelessness were less likely to have GDMT optimized.