Left bundle branch area pacing produces more physiological ventricular activation than biventricular pacing in patients with heart failure and LBBB

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main source(s): National Institute for Research Metabolic and Cardiovascular Diseases, Programme EXCELES, Ministry Health the Czech Republic, grant number NU21-02-00584. Introduction Biventricular pacing (BiV) is an established treatment patients with heart failure dyssynchronous ventricular activation. Left bundle branch area (LBBAP) appears to be a promising alternative BiV-CRT. To date, there insufficient data regarding their effect on reduction dyssynchrony. Purpose compare synchrony during spontaneous rhythm, BiV LBBAP in failure, reduced left ejection fraction (LVEF), LBBB using ultra-high-frequency ECG (UHF-ECG). Methods This was retrospective analysis consecutive indication CRT from two centers. It included QRS morphology, LVEF ≤ 40%, treated by and/or LBBAP-CRT. UHF-ECG were obtained paced rhythms. These parameters calculated: eDYS (time difference between first last activation), Vdmean (average V1-V8 local depolarization durations) QRSd (measured artifact). Results Analyzes performed 80 rhythms, 39 biventricular captures 64 LBBAP, patients. Their mean age 74±10 years, 61% men, LV 31±9 %, 32% had ischemic cardiomyopathy. Both LBBAP-CRT significantly compared rhythm (from 172 ms, 95% CI [168;176] 146 ms [141;152] 143 [139;149] LBBAP). Also, both LBBAP-CRT, i.e., 82 [76;86] 33 [28;37], p<0.001 24 [20;28], p<0.001, 71 [68;73] 59 [56;61], 53 [51;55], LBBAP. Although did not differ (143ms [139;148] vs 146ms [141;152], p=NS), led shorter (24ms [20;28] 33ms [28;38]; p<0.008 (53ms [51;55] 59ms respectively; p<0.003}. Conclusions In LVEF, reduce dyssynchrony rhythm. Our results indicate that associated more physiological activation than