Studies Highlight Permanent Pacemaker Rates Among New-Generation TAVR Devices

PARIS, France—Two single-center studies presented last week at EuroPCR 2016 shed light on the risk of complications, specifically the need for a permanent pacemaker, among patients undergoing transcatheter aortic valve replacement with newer-generation devices.

In the first study, led by Fadi Sawaya, MD (Institut Cardiovasculaire Paris Sud, Massy, France), investigators compared the pacemaker insertion rates between two generations of a balloon-expandable transcatheter heart valve: Sapien S3 and its predecessor, Sapien XT (both Edwards Lifesciences). While the rates of vascular complications and paravalvular leak were significantly reduced with Sapien S3, more patients treated with the new device required a permanent pacemaker after TAVR.

Marco Spaziano, MD (Institut Cardiovasculaire Paris Sud, Massy, France), who presented the results on behalf of the research group, told TCTMD the Sapien S3 device has been used exclusively at their center since 2015. While the higher rate of permanent pacemaker implantation with the newer device over the XT is a concern, he said, the rate is coming down with time as operators gain experience. He said there are properties inherent to the device—some that weren’t fully appreciated when operators began using it—that increase the potential risk of needing a permanent pacemaker after TAVR.

“The device is bulkier, it has a skirt in place to reduce paravalvular leaks, and that skirt might cause conduction abnormalities,” said Spaziano. “You have to be extra careful with the new device with regard to implantation depth so that it’s implanted high enough not to cause any problems.”

In their single-center retrospective study, 507 patients were treated with the Sapien XT valve and 283 patients with the S3 valve over a 5-year period. Regarding patient characteristics, the researchers highlighted the changing TAVR patient over time, noting that patients treated with new Sapien S3 valve tended to have lower EuroSCORE and STS risk scores and were less likely to have NYHA class III or IV heart failure. More patients underwent TAVR via the transfemoral approach with the S3 valve and were more likely to be treated with local anesthesia. Physicians treating patients with the S3 valve were less likely to predilate the valve area than those using Sapien XT.

At 30 days, 2.8% of patients developed major vascular complications with the new-generation valve compared with 9.9% of patients treated with the XT (P < 0.001). Patients treated with the S3 were also significantly less likely to develop mild or worse paravalvular regurgitation (2.4% vs 9.7%, respectively; P < 0.001). In contrast, the need for a new permanent pacemaker occurred in 17.3% of patients treated with Sapien S3 compared with 9.8% of patients treated with the older device (P < 0.05).

Mohammed Abdelghani, MD (Academic Medical Center, Amsterdam, the Netherlands), who chaired the session on conduction disturbances after TAVR, said the results are in line with other reports. Right now, he told TCTMD, it’s clear the occurrence of paravalvular leak and vascular complications are significantly reduced with the Sapien S3, but there’s a tradeoff in terms of higher rates of permanent pacemaker implantation, at least in these early days. Initially, operators did not factor in the importance of implantation depth with the newer Sapien device, but given the learning curve, he expects the risk to decrease over time. Researchers and clinicians are awaiting reports from high-volume clinical centers to determine if this risk declines as operators make the necessary adjustments, said Abdelghani.

For Spaziano, while there is undoubtedly a focus on the higher rate of permanent pacemaker implantation with Sapien S3, there also has been a fourfold reduction in the risk of vascular complications and paravalvular leak, he said. “Yes, there’s a higher rate of pacemakers, but as mentioned, a lot of research has shown the risk is also going down. I think [the S3] is a better valve. It’s just a matter of time before the complication rates go down.”

CoreValve Versus Portico in a Small, Single-Center Analysis

In the second study, investigators compared two different valves—the self-expandable CoreValve (Medtronic) and the repositionable Portico (St. Jude Medical) valve—and reported that the Portico valve was associated with a significantly lower risk of permanent pacemaker implantations following TAVR.

Led by Jessica Roa-Garrido, MD (Complejo Hospitalario Universitario de Huelva, Spain), the investigators tested the two devices in 65 patients ineligible for surgery, including 14 treated with the Portico valve and 51 treated with CoreValve. In the study, just one patient treated with the Portico valve required a permanent pacemaker post-TAVR compared with 17 patients treated with CoreValve (P = 0.021). In addition, the investigators observed a trend toward higher rates of new left bundle branch block and complete atrioventricular block among the CoreValve-treated patients.

Speaking at EuroPCR, Roa-Garrido said the CoreValve does have technical limitations, including limited control and placement accuracy, which can translate into a risk of conduction abnormalities if the device is implanted too deeply. The Portico valve is designed to overcome some of the limitations, she said, as it placed with a minimal protrusion into the left ventricular outflow tract. Moreover, it can be recaptured and repositioned, if needed.

Roa-Garrido acknowledged the limitations of their single-center study, noting it was nonrandomized. In addition, the researchers compared the Portico device against the first-generation CoreValve, rather than the newer CoreValve Evolut R. Still, they observed no significant differences for moderate aortic regurgitation, vascular complications, stroke, or in-hospital mortality between the two valves.

For Abdelghani, while there are some theoretical advantages of recapturing and repositioning the Portico valve during TAVR, this is done only in the minority of patients and not very effectively just yet. He told TCTMD the aim of operators is to keep the procedure short and safe, meaning there is a tendency not to reposition the valve once deployed.

Regarding the higher rate of pacemaker implantations with CoreValve, Abdelghani said this might be explained not only by the use of the first-generation CoreValve but also by significant differences in some of the patient and procedural characteristics. For example, significantly more patients treated with CoreValve had a “deep valve” implantation compared with the Portico device, a finding that could explain the higher rate of pacemaker implantation post-procedure.

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