Dean J. Kereiakes
ORLANDO, Fla. — About one-third of patients who required a permanent pacemaker after transcatheter aortic valve replacement were pacemaker-dependent at 30 days, with no decrease in this percentage at 1 year, according to a subanalysis of the REPRISE III trial.
Additionally, the results indicated that the rate of new pacemaker implantation was higher among patients who received the Lotus valve system (Boston Scientific) vs. the CoreValve TAVR system (Medtronic; 35.5% vs. 19.6%), and that 1-year clinical outcomes were similar regardless of pacemaker status or dependency, according to Dean J. Kereiakes, MD, medical director of the Christ Hospital Heart and Vascular Center and the Lindner Research Center at Christ Hospital, and colleagues.
“Conduction abnormalities leading to permanent pacemaker implant are common after TAVR. As TAVR expands to younger and lower-risk patients, longer-term consequences of pacemaker implant are a concern,” Kereiakes said during his presentation of the data at the American College of Cardiology Scientific Session. “As most pacemaker implants are in temporal association with the TAVR procedure, longer-term pacemaker dependency has not been methodically assessed in TAVR trials.”
To learn more, Kereiakes and colleagues conducted a prespecified protocol-driven assessment of pacemaker dependency as part of the REPRISE III randomized trial.
In REPRISE III, 912 patients with severe symptomatic aortic stenosis were randomly assigned in a 2:1 fashion to TAVR with the Lotus valve system or the CoreValve system. At baseline, 160 patients entered the trial with a pre-existing pacemaker.
Of the 864 patients who underwent successful TAVR and survived to hospital discharge, 249 received a new pacemaker and 455 had no pacemaker. The most common reason for pacemaker implantation was high-degree atrioventricular block (77%).
Of the 864 patients who underwent successful implantation and survived to hospital discharge, 249 received a new pacemaker. The most common reason for pacemaker implantation was high-degree atrioventricular block (77%).
Using an algorithm, the researchers prospectively assessed pacemaker dependency at 30 days and 1 year. At 30 days, approximately 30% to 40% of patients were pacemaker-dependent. By 1 year, Kereiakes said, that percentage had not declined and was roughly 40% to 50%.
Among patients with a new pacemaker, the mean percentage of paced beats at 30 days exceeded 60% and approached 60% at 1 year for both valve types, according to the data. The prevalence of having 50% or more beats paced was greater than 60% at 30 days for both valves and was 37% with CoreValve and 54% with the Lotus system at 1 year.
Clinical outcomes, including all-cause death, CV death, stroke and hospitalization, were worse in patients with a prior pacemaker. Demographically, this patient population was significantly older, had worse left ventricular function and had a higher incidence of atrial fibrillation. However, there were no significant differences in clinical outcomes between patients with a new pacemaker vs. no pacemaker at 1 year.
Results also showed no statistically significant differences in any clinical outcomes between patients with pacemaker dependency vs. no dependency or by pacemaker presence vs. absence.
In patients who received the Lotus valve, independent predictors of pacemaker implantation included right branch bundle block at baseline (OR = 24.51; 95% CI, 9.1-66.02), mean depth of valve implantation (OR = 1.19; 95% CI, 1.06-1.33) and medically treated diabetes (OR = 1.89; 95% CI, 1.17-3.05). Extreme surgical risk, however, was a negative predictor of implantation (OR = 0.43; 95% CI, 0.24-0.77). In patients who received the CoreValve system, only right branch bundle block (OR = 4.58; 95% CI, 1.56-13.45) and mean depth of valve implantation (OR = 1.17; 95% CI, 1.02-1.33) were independent predictors of pacemaker implantation.
The researchers also conducted analyses to identify predictors of pacemaker dependency in patients with a new pacemaker. At 30 days, right branch bundle block at baseline (OR = 4.87; 95% CI, 2.26-10.48), EuroSCORE (OR = 1.1; 95% CI, 1.03-1.18) and mean depth of valve implantation (OR = 1.2; 95% CI, 1.03-1.41) predicted pacemaker dependency. At 1 year, right branch bundle block at baseline (OR = 3.46; 95% CI, 1.7-7.06) and LV outflow tract overstretch (OR = 1.02; 95% CI, 1.01-1.04) were significant predictors of pacemaker dependency. – by Melissa Foster
Kereiakes D, et al. Abstract 1136M-11. Presented at: American College of Cardiology Scientific Session; March 10-12, 2018; Orlando, Fla.
Disclosure: This study was funded by Boston Scientific. Kereiakes reports he is a scientific advisory board member and a consultant for Boston Scientific.