Judah Rajendran, Shivabalan Kathavarayan Ramu, Carl Ammoury, Besir Besir, Akhilesh Khuttan, Odette Iskander, Tamari Lomaia, Ankit Agrawal, Alexander Egoavil, James Yun, Grant Reed, Rishi Puri, Serge Harb, Oussama Wazni, Amar Krishnaswamy, Samir R Kapadia
Patients with preexisting RBBB undergoing balloon-expandable TAVR had a significantly higher and earlier rate of PPM implantation compared to LBBB patients, with no differences in outcomes irrespective of BBB and PPM implantation status. Atrial fibrillation/flutter and RBBB were associated with an increased risk of 30-day PPM implantation, although the risk is acceptable with higher valve implantation.
BACKGROUND: The primary objective of this study was to compare permanent pacemaker (PPM) implantation rates following balloon-expandable transcatheter aortic valve replacement (TAVR) between patients with pre-existing right bundle branch block (RBBB) versus left bundle branch block (LBBB). Secondary objectives were to assess long-term clinical outcomes according to baseline conduction status and post-TAVR PPM implantation and identify independent predictors of PPM implantation.
METHODS: This retrospective study included 380 patients with pre-existing RBBB (n = 269) and LBBB (n = 111) who underwent balloon-expandable TAVR between 2016 and 2020, excluding those with prior pacemakers or implantable cardioverter defibrillators.
RESULTS: Within 30 days following TAVR, PPM implantation was significantly more frequent in patients with preexisting RBBB compared with LBBB (18.59 vs. 7.21%, p = 0.003), whereas early mortality remained low and similar between groups. Patients with RBBB exhibited larger annular dimensions, greater annular calcium burden, and a narrower membranous septum angle. Over long-term 2-year follow-up, there were no significant differences in all-cause mortality or heart failure hospitalization between RBBB and LBBB patients, irrespective of post-TAVR PPM implantation status. On multivariable logistic regression, baseline RBBB (odds ratio [OR] 3.56; 95% CI 1.01-12.58) and prior atrial fibrillation/flutter (OR 4.13; 95% CI 1.63-10.45) were independently associated with increased 30-day PPM risk, whereas deeper right-sided membranous septum implantation depth was associated with lower PPM risk (OR 0.90; 95% CI 0.81-0.99).
CONCLUSIONS: Patients with preexisting RBBB undergoing balloon-expandable TAVR had a significantly higher and earlier rate of PPM implantation compared to LBBB patients, with no differences in outcomes irrespective of BBB and PPM implantation status. Atrial fibrillation/flutter and RBBB were associated with an increased risk of 30-day PPM implantation, although the risk is acceptable with higher valve implantation.