LAUSR

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Transcatheter aortic valve implantation (TAVI) is a worldwide accepted treatment for severe aortic stenosis (AS). Conduction system disturbances, frequently requiring permanent pacemaker (PM) implantation, remain one of the most common procedural complication. Whether the permanent ventricular pacing has a deleterious impact on the prognosis of this population remains unclear. Objectives To assess the long-term impact of permanent PM implantation in clinical outcomes after TAVI. Methods We performed a retrospective analysis of consecutive patients (P) who underwent TAVI between 2009 and 2021 in a single tertiary center.P with a PM implanted before TAVI or with in-hospital mortality were excluded from the analysis. PM implantation post-TAVI was defined as an implant during hospital stay after TAVI or in the first month after discharge. Kaplan Meier survival curves were used to estimate the impact of permanent PM after TAVI, regarding the composite endpoint of all-cause mortality and heart failure (HF) hospitalization during a 4 years follow-up period, and a comparison performed according to the presence or absence of baseline intraventricular conduction disturbances. Results 549 P (82±6.6 years, 56.8% female, left ventricular ejection fraction 53±10%, peak gradient 51±15.6 mmHg, aortic valve area 0.7± 0.2 cm2) were included. At baseline, 108 P (20%) had intraventricular conduction disturbances on ECG (50 P with right bundle branch block [RBBB] and 58 P with left bundle branch block [LBBB]). 127 P (23%) required PM implantation after TAVI. Baseline characteristics were similar between P with and without PM implantation, except for age, gender, previous valvular surgery and RBBB (Table 1). At 48 months follow-up, 35% (n=193) met the composite endpoint, that was similar between both groups (35.8% vs. 34.1%, p=0.731). Kaplan-Meier survival curves revealed no difference in the composite endpoint between the two groups (log-rank p=0.170). Further analysis of subgroups according to the presence or absence of baseline intraventricular conduction disturbances revealed a significant difference among the subgroup of P without previous intraventricular conduction disturbances that underwent PM implantation after TAVI (log rank p=0.02) (Fig 1). This difference in the composite endpoint after PM was not found in the subgroups of P with RBBB (log rank p=0.656) or LBBB (log rank p=0.975) at baseline (Fig 2).* Conclusions Permanent PM implant after TAVI does not have an impact on long-term HF hospitalization and mortality. However, in the specific subgroup of P without previous intraventricular conduction disturbances, PM implantation seems to be associated with worse prognosis. Fig 1. Kaplan meier survival curves