Left Ventricular Dyssynchrony Assessed Using Heart Risk View Predicts Prognosis in Patients With Heart Failure　― The Fukui Heart Risk View Phase Analysis Study ―

BACKGROUND: Left ventricular (LV) dyssynchrony worsens with heart failure (HF) progression. However, the early identification of LV dyssynchrony is challenging, and its prognostic value remains unclear. We aimed to evaluate the prognostic value of LV dyssynchrony based on bandwidth (time width within which 95% of the LV myocardium begins to contract), assessed using Heart Risk View (HRV) analysis of myocardial perfusion scintigraphy data. METHODS AND RESULTS: This was a post hoc analysis of a prospective, non-randomized, single-center cohort study conducted between January 2019 and December 2023. This study included 584 patients (mean age 72.2±13.0 years; 425 [72.8%] males; non-ischemic 29.8%; LV ejection fraction [LVEF] 46.4±15.0%) who were admitted for HF and had LV dyssynchrony evaluated using HRV-based analysis. The composite endpoint was all-cause mortality and HF rehospitalization. Univariate and multivariate logistic regression showed LV dyssynchrony as a significant predictor of HF prognosis (bandwidth threshold 28.0°). Multiple regression analysis identified QRS width, LVEF, and ischemic cardiomyopathy as significant determinants of bandwidth. Prognosis was poorer in high-bandwidth groups defined by the median (21.0°) or threshold bandwidth (28.0°). Combined with B-type natriuretic peptide, bandwidth improved prognostic utility. Bandwidth showed a moderate correlation with QRS width and strong correlations with end-systolic volume and LVEF. CONCLUSIONS: HRV-derived bandwidth is a non-invasive and safe method providing automatic, objective, and reproducible measurements. It is useful for predicting HF prognosis.