Transcatheter aortic valve replacement (TAVR) has become established as a safe and minimally invasive alternative to surgical valve replacement, and its indications have expanded to include younger patients and those at lower surgical risk. Cardiac conduction disturbances remain among the most frequent complications of this procedure, even with newer-generation valves, and are also influenced by patient-specific anatomic features and center experience. The management of these conduction abnormalities therefore remains controversial and continues to represent a clinical challenge, particularly in the absence of high-degree atrioventricular block or complete atrioventricular block.

A subanalysis of the PROMOTE study (PRospective Application of a Pre-Specified Scientific Expert Panel AlgOrithm for the Management of COnduction Disturbances Following Transcatheter Aortic Valve Replacement) was performed. This prospective multicenter study included 2110 patients without previous pacemaker implantation who underwent TAVR. Prophylactic PPI was considered in the presence of QRS prolongation with active electrocardiographic changes, defined as PR or QRS prolongation ≥20 ms over 2 consecutive days, or in the setting of persistent abnormalities associated with QRS >150 ms or PR >240 ms, or after an electrophysiological study showing a His-Ventricle (HV) interval ≥70 ms, taking into account the recommendations issued by a multidisciplinary expert panel in 2019.

The aim of the study was to evaluate the incidence and clinical impact of permanent pacemaker implantation after TAVR.

Patients with prior permanent pacemaker implantation, those who died during the procedure, and those requiring conversion to open cardiac surgery were excluded.

Included patients underwent continuous electrocardiographic (ECG) monitoring during TAVR, and a repeat ECG was performed at the end of the procedure to determine the presence of conduction disturbances.

Among the results, 329 patients who underwent post-TAVR permanent pacemaker implantation were included, of whom 24.3% had a prophylactic indication. The main indication (90%) was new-onset persistent left bundle branch block with QRS >150 ms and/or PR >240 ms, associated with first-degree AVB in 74% of cases. Meanwhile, 8 (10%) patients already had pre-existing QRS abnormalities, including 2 with right bundle branch block and 6 with left bundle branch block with a baseline QRS >130 ms, and subsequently developed new-onset first-degree AVB (n = 5), or had baseline first-degree AVB with progressive PR prolongation (n = 2) despite stable QRS duration after the procedure. Only 1 patient developed new-onset first-degree AVB with baseline left bundle branch block and persistent QRS prolongation >20 ms after TAVR.

The electrocardiographic changes leading to prophylactic permanent pacemaker implantation were distributed as follows: bundle branch block (right or left, with QRS >150 ms) and first-degree AVB with PR >240 ms (30%), left bundle branch block with QRS >150 ms and PR ≤240 ms (35%), PR >240 ms and left bundle branch block with QRS >150 ms (32.5%), and PR ≤240 ms with new-onset left bundle branch block and QRS >150 ms (2.5%).

Among patients with new-onset left bundle branch block and QRS >150 ms (n = 41), 39% underwent prophylactic permanent pacemaker implantation after an electrophysiological study.

The time to definitive pacemaker implantation was longer in the prophylactic group than in the nonprophylactic group (6 vs 4 days; p < .001).

Thirty-day clinical outcomes were similar in the prophylactic and nonprophylactic groups, but the median ventricular pacing percentage was significantly lower in the prophylactic group (2% vs 73%; p < .001), with a high proportion of patients showing a ventricular pacing percentage <1% (42.6% vs 14.5%; p < .001). Mean patient age was 81 ± 7 years, 34% were women, and the mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 4.0 ± 2.8%.

Despite the use of newer-generation transcatheter valve systems, 1 in 10 patients undergoing TAVR still requires permanent pacemaker implantation after the procedure. Prophylactic permanent pacemaker implantation after a positive electrophysiological study (HV interval ≥70 ms) did not affect pacing burden at follow-up (median, 2% vs 1.9% in patients without electrophysiological study; p = .585).

COMMENTARY:

The attempt to validate the 2019 expert panel algorithm for post-TAVR conduction disturbances through the PROMOTE study allowed this subanalysis to better define the true clinical effect of prophylactic permanent pacemaker implantation in that setting.

The management of patients with post-TAVR electrocardiographic changes, particularly when high-degree block or complete block is absent, remains challenging. Current European Society of Cardiology guidelines suggest ambulatory monitoring or electrophysiological study in patients with new-onset left bundle branch block with QRS ≥150 ms or PR ≥240 ms after TAVR (Class IIa recommendation). Electrophysiological study should be performed at least 3 days after the procedure, and an HV interval ≥70 ms is considered the threshold at which permanent pacemaker implantation may be considered (Class IIb recommendation).

Approximately one-fourth of patients receiving permanent pacemaker implantation after TAVR had a prophylactic indication. However, the similar clinical outcomes and very low pacing burden at 30 days in the prophylactic group call into question the routine use of prophylactic implantation after TAVR.

In fact, more than 35% of patients who underwent prophylactic implantation had <10% pacing during the first year after TAVR, underscoring that isolated pre-TAVR right bundle branch block cannot be regarded as a sufficiently specific predictor of chronic pacemaker requirement.

That said, the development of persistent left bundle branch block after TAVR has been independently associated with an increased risk of sudden cardiac death during follow-up, particularly when QRS duration exceeds 160 ms. This suggests that prophylactic permanent pacemaker implantation might reasonably be considered in selected cases to reduce the risk of sudden death, and that the indication should ultimately be individualized according to overall risk and electrocardiographic findings.

REFERENCE:

Fischer Q, Nombela-Franco L, Muntané-Carol G, Veiga G, Regueiro A, Nazif T, et al. Prophylactic Permanent Pacemaker Implantation After Transcatheter Aortic Valve Replacement. JACC Clin Electrophysiol. 2025 Nov;11(11):2484-2492. doi: 10.1016/j.jacep.2025.07.028.