Prognostic impact of percentage of ventricular pacing in patients requiring pacemaker implantation after transcatheter aortic valve replacement

Abstract

Abstract Background Despite the continuous developments of transcatheter aortic valve implantation (TAVI), around 15% of the patients (P) who undergo this procedure require permanent pacemaker (PM). Right ventricular pacing (RVP), particularly with a cumulative percentage of ventricular pacing (CVp) above 40%, has been associated with detrimental effects on ventricular function and an increased risk of cardiovascular events in non-TAVI patients. Aim To evaluate the long-term prognostic significance of RVP, regarding overall mortality and the combined endpoint of overall mortality/heart failure hospitalization in P requiring a PM after TAVI. Methods We retrospectively examined P who underwent TAVI with a self-expanding valve from 2009 to 2020 at our institution. All P had pre-procedural clinical evaluation, cardiac computed tomographic angiography, transthoracic echocardiography and electrocardiography performed. CVp was determined from stored PM data. P with previous PM were excluded. Post-TAVI PM implantation was defined as a device implantation during hospital stay or during the first month after discharge. Results 474P, 57% male, mean age 81.7±6.5 years with a mean left ventricular ejection fraction of 51.5±14.6% were analysed. Mean follow-up was 18.7 months. Mean STS score and mean Euroscore II were, respectively, 6.89% and 5.76%. Mean gradient was 51.67 mmHg and mean aortic valve area 0.71 cm2. After TAVI, 104P (21.9%) required PM implantation, with a mean CVp of 65.3±43.4%. Post-TAVI PM was not associated with a worse outcome - overall mortality: HR 1.13, 95% CI 0.72 – 1.78, p=0.57; combined mortality/heart failure hospitalization: HR 1.22, 95% CI 0.87 – 1.70, p=0.24. The follow-up Kaplan-Meier curves according to the need for PM post-TAVI were similar: log rank p=0.24. A CVp cut-off of 40% was not associated with any of the study endpoints - overall mortality: HR 1.72, 95% CI 0.38–7.86, p=0.48; combined mortality/heart failure hospitalization: HR 1.32, 95% CI 0.45–3.91, p=0.61. Also, a CVp cut-off of 40% did not provide an accurate risk stratification as survival free of events was similar between these P and those below this cut-off (log rank p=0.11) and in comparison, with P without PM (log rank p=0.65). Conclusions In P submitted to TAVI with a self-expanding valve, the need for PM implantation is common, but not associated with increased risk of total mortality or heart failure hospitalization during a 18 months follow-up period. A CVp cut-off of 40% showed poor discriminative ability regarding long-term events in this population. Funding Acknowledgement Type of funding sources: None.