Improving the Characterization of Stage A and B Heart Failure by Adding Global Longitudinal Strain

Abstract

Background: Current guidelines distinguish stage B heart failure (SBHF) (asymptomatic left ventricular [LV] dysfunction) from stage A heart failure (SAHF) (asymptomatic with heart failure [HF] risk factors) on the basis of myocardial infarction, LV remodeling (hypertrophy or reduced ejection fraction [EF]) or valvular disease. However, subclinical HF with preserved EF may not be identified with these criteria.

Objectives: The purpose of this study was to assess the prediction of incident HF with global longitudinal strain (GLS) in patients with SAHF and SBHF.

Methods: The authors analyzed echocardiograms (including GLS) in 447 patients (age 65 ± 11 years; 77% male) enrolled in a prospective study of HF in individuals at risk of incident HF, with normal or mildly impaired EF (≥40%). Long-term follow-up was obtained via data linkage. Analysis was performed using a competing risks model.

Results: After a median of 9 years of follow-up, 50 (10%) of the 447 patients had new HF admissions, and 87 (18%) died. In multivariable analysis, all imaging variables were independent predictors of HF admissions, including left ventricular ejection fraction (LVEF) (HR: 0.97 [95% CI: 0.94-0.99]), LV mass index (HR: 1.01 [95% CI: 1.00-1.02]), left atrial volume index (HR: 1.02 [95% CI: 1.00-1.05]), and E/e' (HR: 1.05 [95% CI: 1.01-1.24]), incremental to clinical variables (age and Charlson comorbidity score). However, the addition of GLS provided value incremental to both clinical and other echocardiographic parameters (P = 0.004). Impaired GLS (<18%) (HR: 4.09 [95% CI: 1.87-8.92]) was independent and incremental to all clinical and other echocardiographic variables in predicting HF, and impaired LVEF, left ventricular hypertrophy, left atrial enlargement, high E/e', or SBHF were not predictive.

Conclusions: The inclusion of GLS as a criterion for SBHF would add independent and incremental information to standard markers of SBHF for the prediction of subsequent HF admissions.

Keywords: heart failure; outcomes; risk factors; stage B heart failure; strain.