Abstract 13007: Change in QRS 3D Voltage Time Integral (3D QRS Area) Predicts Left Ventricular Reverse Remodeling in Sacubitril-Valsartan Treated Patients With Left Bundle Branch Block

Abstract

Introduction: The instantaneous absolute 3D ECG voltage integrated over the duration of QRS (VTI QRS-3D ) is an improved marker of left ventricular (LV) electrical dyssynchrony compared to QRS duration (QRSd). Among patients with left bundle branch block (LBBB) receiving heart failure medical therapy, the relationship between electrical remodeling assessed by VTI QRS-3D and structural LV remodeling is unclear. Hypothesis: Reduction in VTI QRS-3D is correlated with left ventricular reverse remodeling. Methods: We retrospectively studied heart failure patients with underlying LBBB who were treated with sacubitril-valsartan for ≥3 months between January 2014 - June 2019. Echocardiograms and 12-lead ECGs were collected pre and post sacubitril-valsartan treatment. ECGs were converted to orthogonal X, Y, Z leads using Kors matrix, to then obtain VTI QRS-3D . Echocardiographic LV measures included end-diastolic volume (LVEDV), end-systolic volume (LVESV) and ejection fraction (LVEF). We calculated the Pearson correlations between electrical variables and changes in echocardiographic measures pre to post treatment. Results: We included 56 patients (mean age 64.0±13.5 years, men 53.6%, baseline LVEF 25.2±9.1%). ΔVTI QRS-3D was strongly correlated with improvement in all 3 echocardiographic measures (all p ≤0.01). ΔVTI QRS-3D outperformed ΔQRSd in predicting echocardiographic response (Table). Conclusions: In heart failure patients with LBBB on medical therapy, electrical remodeling assessed as reduction in VTI QRS-3D is strongly predictive of LV structural and functional reverse remodeling.