Background: A lower rate of permanent pacemaker (PPM) has been linked to a target aortic implantation height (AIH) >0.70, following transcatheter aortic valve replacement (TAVR) with the SAPIEN 3 valve. Based on clinical experience, it was hypothesized that a higher AIH (≥0.85) would lower the rate of PPM implantation.
Methods: A total of 127 patients (66 females, 61 males; mean age 82 ± 8 years) underwent TAVR with the SAPIEN 3 valve between May 2015 and July 2016. AIH was defined as the proportion of the valve frame above the aortic annulus in the post-deployment aortogram. A target AIH (≥0.70) was achieved in 113 patients (89%). Cases were stratified into a High Implantation (HI) group (AIH ≥0.85; 33 patients) or a Standard Implantation (SI) group (AIH <0.85; 94 patients).
Results: The mean Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score of all patients was 6.4 ± 3.5%. Preoperative right bundle branch block (RBBB) was prevalent in 13% of SI patients, and in 18% of HI patients (p = 0.56). There were no significant differences in operative mortality (3.2% versus 0%), median length of stay (2 days versus 3 days) and incidence of moderate-to-severe paravalvular leak (3.2% versus 0%; all p >0.410) between SI and HI patients, respectively. Likewise, the incidence of new PPM did not differ between the two groups (12% in HI versus 13% in SI; p ≥0.99). The mean AIH was similar for patients with PPM implantation (0.80 ± 0.08) compared to those without (0.78 ± 0.06; p = 0.520). Preoperative RBBB was significantly associated with PPM implantation (odds ratio (OR) 10.1; p = 0.002), and patients who underwent PPM implantation had a higher operative mortality (12.5% versus 1%; p = 0.040).
Conclusions: Among TAVR patients who received the SAPIEN 3 heart valve, a higher AIH (≥0.85) was not associated with a lower rate of PPM implantation or increased operative mortality. Prior RBBB was the only independent risk factor for new PPM implantation. Long-term follow up is crucial in determining the clinical significance of PPM implantation.