Efficacy on resynchronization and longitudinal contractile function comparing His-bundle pacing with conventional biventricular pacing: a substudy to the His-alternative study

• Published in: European heart journal cardiovascular imaging Vol. 25; no. 1; p. 66
• Main Authors: Højgaard, E V, Philbert, B T, Linde, J J, Winsløw, U C, Svendsen, J H, Vinther, M, Risum, N
• Format: Journal Article
• Language: English
• Published: England 21.12.2023
• Subjects: Arrhythmias, Cardiac - therapy; Bundle-Branch Block - diagnostic imaging; Bundle-Branch Block - therapy; Cardiac Resynchronization Therapy - methods; Electrocardiography - methods; Heart Failure - diagnostic imaging; Heart Failure - therapy; Humans; Stroke Volume; Treatment Outcome; Ventricular Function, Left; biventricular pacing; heart failure; left bundle branch block; His-bundle pacing; cardiac resynchronization therapy; 2D speckle tracking
• ISSN: 2047-2412
• DOI: 10.1093/ehjci/jead181

His-bundle pacing has emerged as a novel method to deliver cardiac resynchronization therapy (CRT). However, there are no data comparing conventional biventricular (BiV)-CRT with His-CRT with regard to effects on mechanical dyssynchrony and longitudinal contractile function. Patients with symptomatic heart failure, left ventricular ejection fraction ≤ 35%, and left bundle branch block (LBBB) by strict ECG criteria were randomized 1:1 to His-CRT or BiV-CRT. Two-dimensional strain echocardiography was performed prior to CRT implantation and at 6 months after implantation. Differences in changes in mechanical dyssynchrony (standard deviation of time-to-peak in 12 midventricular and basal segments) and regional longitudinal strain in the six left ventricular walls were compared between the BiV-CRT and His-CRT groups.In the on-treatment analysis, 31 received BiV-CRT and 19 His-CRT. In both groups, mechanical dyssynchrony was significantly reduced after 6 months [BiV group from 120 ms (±45) to 63 ms (±22), P < 0.001, and His group from 116 ms (±54) to 49 ms (±11), P < 0.001] but no significant differences in changes could be demonstrated between groups [-9.0 ms (-36; 18), P = 0.50]. Global longitudinal strain (GLS) improved in both groups [BiV group from -9.1% (±2.7) to -10.7% (±2.6), P = 0.02, and His group from -8.6% (±2.1) to -11.1% (±2.0), P < 0.001], but no significant differences in changes could be demonstrated from baseline to follow-up [-0.9% (-2.4; -0.6), P = 0.25] between groups. There were no regional differences between groups. In heart failure, patients with LBBB, BiV-CRT, and His-CRT have comparable effects with regard to improvements in mechanical dyssynchrony and longitudinal contractile function.