Myocardial Strain for Identification of β-Blocker Responders in Heart Failure with Preserved Ejection Fraction

Background: Beta-blockers improve survival in patients with heart failure (HF) with reduced ejection fraction, but their effect is inconclusive in those with HF with preserved ejection fraction (HFpEF). The aim of this study was to evaluate the efficacy of beta-blockers according to global longitudinal strain (GLS) in patients with left ventricular ejection fraction (LVEF) >= 40%. Methods: The Strain for Risk Assessment and Therapeutic Strategies in Patients with Acute Heart Failure registry included 4,312 patients with acute HF at three tertiary hospitals. A total of 1,969 patients with LVEF 40% were included in this study. The patients were categorized as having either HF with midrange ejection fraction (40% <= LVEF < 50%; n = 692) or HFpEF (LVEF >= 50%; n = 1,277) and were classified as having GLS < 14% (n = 1,040) or GLS >= 14% (n = 929) on the basis of the best cutoff value derived from receiver operating characteristic curve analysis. GLS was indicated as an absolute value. The primary end point was 5-year all-cause mortality. A multivariate Cox proportional-hazard model was used to estimate the differential effect of beta-blockers on mortality in each prespecified group, and inverse-probability treatment-weighted analysis was performed to minimize confounders. Results: Overall, 752 patients (38.2%) died within 5 years. After adjustment for significant covariates, beta-blocker use was associated with reduced risk for all-cause mortality in patients with GLS < 14% (HF with midrange ejection fraction: adjusted hazard ratio, 0.64; 95% CI, 0.46-0.90; P = .010; HFpEF: adjusted hazard ratio, 0.57; 95% CI, 0.41-0.80; P = .001), but not in those with GLS >= 14%. Similar findings were observed in the inverse-probability treatment-weighted population. No significant interaction between beta-blockers and other variables was found except for GLS. Conclusions: For patients with HF and LVEF >= 40%, the use of beta-blockers is associated with improved survival in those with GLS < 14%. Stratification of patients with HFpEF using GLS may identify those who could benefit from beta-blockers.