Association of the frontal QRS-T angle with adverse cardiac remodeling, impaired left and right ventricular function, and worse outcomes in heart failure with preserved ejection fraction

Background No prior studies have investigated the association of QRS-T angle with cardiac structure and function and outcomes in heart failure with preserved ejection fraction (HFpEF). The aim of this study was to test the hypothesis that increased frontal QRS-T angle is associated with worse cardiac function and remodeling and adverse outcomes in HFpEF. Methods A total of 376 patients with HFpEF (i.e., symptomatic heart failure with left ventricular ejection fraction > 50%) were prospectively studied. The frontal QRS-T angle was calculated from the 12-lead electrocardiogram. Patients were divided into tertiles by frontal QRS-T angle (0 -26, 27 -75, and 76 -179), and clinical, laboratory, and echocardiographic data were compared among groups. Cox proportional-hazards analyses were performed to determine the association between QRS-T angle and outcomes. Results The mean age of the cohort was 64 ± 13 years, 65% were women, and the mean QRS-T angle was 61 ± 51. Patients with increased QRS-T angles were older; had lower body mass indices; more frequently had coronary artery disease, diabetes, chronic kidney disease, and atrial fibrillation; and had higher B-type natriuretic peptide levels (P <.05 for all comparisons). After multivariate adjustment, patients with increased QRS-T angles had higher B-type natriuretic peptide levels in addition to higher left ventricular mass indices, worse diastolic function parameters, more right ventricular remodeling, and worse right ventricular systolic function (P <.05 for all associations). QRS-T angle was independently associated with the composite outcome of cardiovascular hospitalization or death on multivariate analysis, even after adjusting for B-type natriuretic peptide (heart rate for the highest QRS-T tertile, 2.0; 95% confidence interval, 1.2-3.4; P =.008). Conclusions In HFpEF, increased QRS-T angle is independently associated with worse left and right ventricular function and remodeling and adverse outcomes.