Prevalence and predictors of permanent pacemaker implantation in patients with aortic stenosis undergoing transcatheter aortic valve implantation: a prospective cohort study.

Objectives: The primary objectives were to identify the predictors of new permanent pacemaker implantation in patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). The secondary objectives were to investigate the temporal changes in permanent pacemaker implantation following TAVI and its impact on long-term prognosis.

Design: Prospective observational cohort study of patients with AS undergoing TAVI.

Setting: Single-centre study conducted at a tertiary hospital in Western Norway between 2012 and 2019.

Participants: Among 600 consecutive patients with severe AS who were treated with TAVI, 52 patients with permanent pacemaker prior to TAVI were excluded. The remaining 548 patients were included in the present study.

Baseline Measures: An evaluation of baseline risk factors, 12-lead ECG and echocardiography.

Primary Outcome Measures: The need for a new pacemaker implantation ≤30 days following TAVI and all-cause death.

Results: The mean age was 80.6±6.7 years, and 50% were males. Among the 548 eligible patients, 173 (31.6%) underwent pacemaker implantation ≤30 days following TAVI, evenly distributed between females and males (29.6% vs 33.6%, p=0.317), with higher implant rates at low-volume phase (2012-2015) and lower implant rates at high-volume phase (2016-2019) (45.8% vs 23.9%, p<0.001). On multivariable analysis, an abnormal electrocardiogram (OR 1.73; 95% CI 1.14 to 2.63, p=0.010), right bundle branch block (OR 2.23; 95% CI 1.09 to 4.59, p=0.028) and atrial fibrillation (OR 1.89; 95% CI 1.24 to 2.88, p=0.003) at baseline were strong predictors of pacemaker implantation. The type of bioprosthesis, but not size, was associated with permanent pacemaker implantation (mechanically expandable valves OR 3.48, 95% CI 2.16 to 5.59; balloon-expandable valves OR 0.07, 95% CI 0.02 to 0.29, both p<0.001)-irrespective of age and sex. During a median follow-up of 60.4 months (range 3-131 months), permanent pacemaker implantation following TAVI was not associated with all-cause mortality (HR 0.89; 95% CI 0.69 to 1.16, p=0.403).

Conclusions: In the current study, the rates of permanent pacemaker implantation following TAVI decreased substantially from the early low-volume phase to the late high-volume phase. An abnormal baseline ECG, right bundle branch block, atrial fibrillation and bioprosthesis selection remained important predictors of permanent pacemaker implantation. Permanent pacemaker implantation following TAVI had no impact on short or long-term survival.

Ethics And Dissemination: The Regional Committees for Medical and Health Research Ethics (approval number: REK vest 33814/2019) and the Institutional Data Protection Services approved the study protocol. The dissemination of study findings was through peer-reviewed publication, presentation at national and international scientific meetings and conferences.

Trial Registration Number: NCT04417829.