Late arrhythmic burden in patients with left bundle branch block after TAVR with the Evolut valve.

Objective: Arrhythmic burden after discharge in patients with new-onset persistent left bundle branch block (NOP-LBBB) following transcatheter aortic valve replacement (TAVR) with Evolut devices remains largely unknown. The aim of this study is to assess the incidence and type of arrhythmias at 2-year follow-up in patients with NOP-LBBB post-TAVR.

Results: This is a prospective multicentre study including 88 patients with LBBB persisting for ≥3 days post-implantation. Before discharge, an implantable loop recorder (REVEAL XT/LINQ) was implanted; patients had continuous monitoring for 2 years. Arrhythmic events were adjudicated in a central core lab. Of the arrhythmic events, 411 were detected in 58 patients [65.9%; 2 (1-4) events per patient]. Symptoms were reported in 12/58 (20.7%), and therapy was changed in 25/58 (43.1%). There were 101 bradyarrhythmic events in 33 patients [35 high-grade atrioventricular block (HAVB) and 66 severe bradycardia]. The HAVB incidence was higher in the early (4-week) phase and remained stable over time, whereas severe bradycardia increased after 1 year. Permanent pacemaker was required in 11 (12.5%) patients (6.8% and 5.7% in the first and second year, respectively). There were 310 tachyarrhythmic events in 29 patients (120 AF/AFL, 111 AT, 72 SVT, 6 NSVT, and 1 VT); its incidence decreased throughout the 2 years. New AF/AFL episodes occurred in 20/69 patients [29%; symptomatic in 2/20 (10%)].

Conclusions: Patients with NOP-LBBB post-TAVR with Evolut devices exhibited a high burden of late arrhythmias, with events occurring in two-thirds of patients and leading to treatment changes in about half of them. These data should inform future studies on cardiac monitoring devices for follow-up and treatment optimization in this challenging population.