The interplay between permanent pacemaker implantation and mortality in patients treated by transcatheter aortic valve implantation: A systematic review and meta-analysis

Background: Previous implantation of a permanent pacemaker (PPM) is common among patients undergoing transcatheter aortic valve implantation (TAVI). Moreover, onset of conduction disturbances needing new PPM implantation after TAVI is frequent. The interplay of pre-existing and new-PPM on mortality after TAVI remains controversial. Methods: We performed a systematic review and study-level meta-analysis on the influence of PPM on mortality after TAVI. Patients were divided into 3 groups: pre-existing PPM, new-PPM (implantation within 30 days after TAVI) and no-PPM (without PPM up to 30 days after TAVI). Outcomes were compared using pairwise and network meta-analysis. Results: A total of 28 studies including 40,016 subjects were eligible. Patients of the no-PPM group had a lower mortality outcome compared to the rest of the study population (relative risk [RR] 0.76, 95% confidence interval [CI] 0.68-0.85, P<0.0001) at median follow up of 16.3 months. In particular, patients with a pre-existing PPM (RR 1.43, 95% CI 1.26-1.62, P<0.0001), but not those with a newly implanted PPM (RR 1.08, 95% CI 0.99-1.18, P=0.10), had a significantly higher mortality compared to patients of the no-PPM group. Moreover, meta-regression analysis showed that the transapical approach rate had a detrimental interaction with pre-existing PPM on mortality (P=0.03). Conclusion: Compared to patients without PPM, those with a pre-existing PPM before TAVI had higher mortality, in particular if treated by the transapical approach. New-PPM implantation did not have a negative relation on mid-term outcome.