P6017Permanent left bundle branch area pacing for atrioventricular block: feasibility, safety and acute effect

Abstract

Abstract Background Left bundle branch area pacing (LBBAP), lacks adequate evaluation for AVB. Purpose We aimed to assess the feasibility, safety, and acute clinical outcomes of permanent LBBAP in patients with AVB. Methods We retrospectively recruited AVB patients with indication for ventricular pacing who had underwent LBBAP from May to Sep. 2018. ECG characteristics, pacing parameters, echocardiographic parameters and adverse events were evaluated during follow-up. Successful LBBAP was defined as the paced QRS morphology of RBBB pattern and QRSd less than 130ms. Results A total of 33 patients were involved in this study (mean age: 55.1±18.5 years; 66.7% male, 48.4% with bundle branch block,BBB). LBBAP was successfully performed in 90.9% (30/33) of all patients. The mean capture threshold of LBBAP was 0.76±0.26 V/0.4 ms during the procedure and 0.64±0.20 V/0.4ms at 3-month follow-up. The paced QRSd was 112.8±10.9 ms during the procedure and 116.8±10.4ms at 3-month follow-up. Baseline left or right BBB was corrected by LBBAP (153.3±27.8 ms vs. 122.2±9.9 ms) with a success rate of 68.7% (11/16). One ventricular septal lead perforation occurred soon after the procedure and LBBAP was successfully repeated by lead revision. Cardiac function and left ventricular synchronization at three-month follow-up presented slightly improvement as compared with baseline. Table 1. Complications and changes in pacing parameters within 3 months after LBBAP Pacing parameters LBBAP (N=30) During the procedure Before discharge 3-month follow up Sensing amplitude, mV 14.4±5.1 15.8±11.7 14.6±4.6 Pacing threshold@0.4ms, V 0.76±0.26 0.59±0.16 0.64±0.20 Pacing impedance, Ω 691.7±133.8 588.0±79.3 554.7±93.7 Paced QRSd at 3.0V@0.4 ms output, ms 112.8±10.9 114.4±14.2 116.8±10.4 VP, % NA NA 79.4±24.6 Complications, n (%) 1 (3.3) 0 (0.0) 0 (0.0) Infection, n (%) 0 (0.0) 0 (0.0) 0 (0.0) Septal perforation, n (%) 1 (3.3) 0 (0.0) 0 (0.0) Dislodgement, n (%) 0 (0.0) 0 (0.0) 0 (0.0) QRSd, QRS duration; VP, ventricular pacing percentage. Figure 1. Characteristics of LBBAP Conclusion Permanent LBBAP yielded stable threshold, narrow QRSd and preserved left ventricle synchrony with few complications. Our preliminary results indicate that LBBAP holds promise as an attractive physiological pacing strategy for AVB.