Pacemaker Risk Stratification in Patients With Pre-existing Right Bundle Branch Block Undergoing Transcatheter Aortic...

Patients with pre-existing right bundle branch block (RBBB) undergoing transcatheter aortic valve replacement (TAVR) face a high risk of permanent pacemaker implantation (PPI). However, additional predictors of PPI in this subpopulation are unknown.

This retrospective, multicenter study enrolled 530 patients with baseline RBBB without pacemakers undergoing TAVR in native aortic valve stenosis. The primary endpoint was incidence of PPI at 30 days and predictors of the primary endpoint were used to determine PPI risk.

PPI occurred in 229 (42.2%) patients at 30 days. Female sex (49.5% in women vs 39.9% in men, P = 0.034), prolonged PR segment (61.1% if PR > 240 ms vs 42.2% if PR < 240 ms), and use of self-expanding valves (51.9% vs 36.2% in balloon-expandable valves, P = 0.001) were associated with higher rates of PPI at 30 days. Other electrocardiographic parameters (QRS duration or left fascicular hemiblock) were unrelated to PPI. Computed tomography subanalysis showed that valve-to-annulus oversizing > 10% and left ventricular outflow tract smaller than the annulus were significantly associated with PPI (P = 0.026 and P = 0.017, respectively). Multivariate analysis demonstrated that the best predictive model for PPI included female sex (odds ratio [OR] 1.38, P = 0.088), PR > 240 ms (OR 2.62, P = 0.008), and self-expanding valves (OR 1.95, P < 0.001). The probability estimation for PPI was 76.8% with all these factors present compared with 32.0% in the absence of these factors.

Among patients with baseline RBBB undergoing TAVR, PPI was more frequent in women with PR > 240 ms and treated with self-expanding valves. Appropriate risk stratification may help to detect low- or high-risk individuals of PPI.