Clinical benefits of switching from right ventricular apical pacing to left bundle branch area pacing in patients with complete atrioventricular block: acute results

Aim. To evaluate the impact of upgrading from right ventricular apical pacing (RVAP) to left bundle branch area pacing (LBBAP) on the clinical and functional status of patients with complete atrioventricular block (AVB) in the acute period.

Methods. The study included 30 patients with complete AVB and previously implanted pacemakers. All patients underwent elective pacemaker replacement with repositioning of the ventricular lead from the apical site to the LBBAP area. Clinical and instrumental assessments were performed before surgery and on postoperative day 5, including electrocardiography, echocardiography, a 6-minute walk test and quality of life evaluation using the EQ-5D questionnaire.

Results. After conversion to LBBAP, QRS duration decreased (from 158.5±25.5 ms to 111.2±13.8 ms, p < 0.05), interventricular and intraventricular dyssynchrony indices (interventricular mechanical delay and time to peak systolic velocity) were reduced, and the degree of mitral regurgitation decreased. The 6-minute walk test distance increased from 368.7±87.06 m to 466.15±127.2 m, and patients reported improved quality of life according to the EQ-5D questionnaire.

Conclusion. Conversion from RVAP to LBBAP leads to improved electrical and mechanical synchrony of cardiac function, which is associated with increased exercise tolerance and enhanced quality of life. LBBAP demonstrates potential as a more physiological and effective alternative to conventional apical pacing.

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