Cardiac resynchronisation therapy in patients with left bundle branch block with residual conduction

• Published in: Indian pacing and electrophysiology journal 2021-01, Vol.21 (1), p.14-17
• Main Authors: Grebmer, Christian, Friedrich, Lena, Semmler, Verena, Kottmaier, Marc, Bourier, Felix, Brkic, Amir, Blazek, Patrick, Weigand, Severin, Connor, Matthew O’, Deisenhofer, Isabel, Hessling, Gabriele, Kolb, Christof, Lennerz, Carsten
• Format: Article
• Language: English
• Subjects: Cardiac resynchronisation therapy; Heart failure; Left bundle branch block; Left bundle branch block with residual conduction; Original
• ISSN: 0972-6292; 0972-6292
• DOI: 10.1016/j.ipej.2020.10.006

To evaluate whether left bundle branch block with residual conduction (rLBBB) is associated with worse outcomes after cardiac resynchronisation therapy (CRT). All consecutive CRT implants at our institution between 2006 and 2013 were identified from our local device registry. Pre- and post-implant patient specific data were extracted from clinical records. A total of 690 CRT implants were identified during the study period. Prior to CRT, 52.2% of patients had true left bundle branch block (LBBB), 19.1% a pacing-induced LBBB (pLBBB), 11.2% a rLBBB, 0.8% a right bundle branch block (RBBB), and 16.5% had a nonspecific intraventricular conduction delay (IVCD) electrocardiogram pattern. Mean age at implant was 67.5 years (standard deviation [SD] = 10.6), mean left ventricular ejection fraction (LV EF) was 25.7% (SD = 7.9%), and mean QRS duration was 158.4 ms (SD = 32 ms). After CRT, QRS duration was significantly reduced in the LBBB (p