CI-569-03 LEFT BUNDLE BRANCH AREA PACING FOR CARDIAC RESYNCHRONIZATION THERAPY: A MULTICENTER PROSPECTIVE STUDY

The societal guidelines recommend physiologic pacing for patients who are anticipated to require high burden ventricular pacing. This includes patients with a) AV block and LVEF between 35-50%, b) tachy-cardiomyopathy undergoing AV node ablation, c) chronic RV pacing induced cardiomyopathy, and d) failed CS lead implants as a rescue CRT strategy. There are limited data on the utility of left bundle branch area pacing (LBBAP) as an alternative to CRT in this patient sub-groups. To evaluate the feasibility and outcomes of LBBAP in patients eligible for CRT. Patients referred for pacemaker implantation at two academic centers between 02/2019-07/2021 were considered for LBBAP. LBBAP was performed by implanting the 3830 lumenless lead using the C315 fixed curve or C304 His deflectable sheath (Medtronic, MN). Implant success rates, complications, electrophysiological and echocardiographic parameters were assessed. LBBAP was successful in 135/161 CRT eligible patients (84%). Mean age was 75±9 years and 34% were women. Failed cases were more likely to be men and had wider QRS duration at baseline (163±34 vs. 137±32, p<0.001) compared with successful cases. Among successful cases 20% had RBBB, 25% had LBBB, 3% had IVCD, 12% were RV paced and 24% had narrow QRS complexes. Pacing indications: AV block with LVEF 35%-50%: 48%, rescue CRT or pacing induced cardiomyopathy: 40% and refractory AF with LVEF<50%: 12%. Mean procedural duration was 84±45 mins and mean fluoroscopic time was 14±13 mins. Paced QRSd was 116±14 ms. Mean LV activation time was 74.6±12 ms at high output and 78±13 ms at low output. LBB potentials were noted in 20% patients. Transition from non-selective to selective LBBA or septal pacing was noted in 67%. Mean follow-up was 299±220 days (median 248 days). Lead parameters remained stable during intermediate term follow-up (Fig A). Left ventricular EF improved significantly from 36.5±10% to 45.4±12% during follow-up (Fig B). The were no chronic LBBAP lead related complications such as lead perforation, threshold rise >3V or lead revision. LBBAP is safe and feasible alternative for CRT. LBBAP is associated with stable intermediate term lead parameters, low complication rate, and is associated with improved echocardiographic outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)