Does Pacemaker Implantation During TAVI Impact Survival?

Shelley Wood

November 06, 2012

LOS ANGELES — Pacemaker implantation during or after a transcatheter aortic-valve implantation (TAVI) has no impact on mid-term survival, but does increase hospital stay, a new analysis has found.

Dr Jérome van Rothem (Hôpital Privé Jacques Cartier, Massy, France) presented the results here today at the American Heart Association 2012 Scientific Sessions.

"The incidence of pacemaker implantation is very different between balloon-expandable and self-expandable prosthesis," van Rothem noted. "Pacemaker implantation is typically considered to be a minor complication . . .  but there is only limited information available about the prognostic impact of this complication."

van Rothem and colleagues compared 30-day and one-year outcomes following TAVI in patients who had or had not received a pacemaker at the time of their procedure. Patients were treated at one of three tertiary centers in France over a six-year period (2007 to 2012). In all, 960 patients underwent TAVI, treated using either the Edwards Sapien valve (70%) or Medtronic CoreValve (30%). Of the 773 patients with no pacemaker prior to their valve procedure, 112 had a new pacemaker implantation during or immediately following the procedure.

Pacemaker implantation was much more common among patients treated with CoreValve (21.2%)--a well-established pattern related to the self-expanding nature of this device. Just 7.6% of Sapien-treated patients received a pacemaker. The overall pacemaker implantation rate for the series was 11.7%--"very low in our study," van Rothem said.

Group Differences

Most patient-level characteristics were similar between the pacemaker-treated and no-pacemaker groups, with some exceptions. Sapien-treated patients with a higher body-mass index and body-surface area were more likely to get a pacemaker.

In an analysis of procedural characteristics, investigators noticed that pacemaker implantation was associated with use of a larger-diameter prosthetic, but, at least in those treated with the Sapien valve, patients did not tend to also have a significantly larger annulus size. Pacemaker implantation was also slightly more common in patients treated via a transfemoral procedure.

Following the procedure, patients with and without pacemakers had similar echocardiographic results, including similar rates of aortic regurgitation. In-hospital outcomes were also no different between pacemaker groups, although hospital stays were typically longer among pacemaker-treated patients, by roughly one day. Acute kidney injury was significantly higher among patients who underwent pacemaker implantation.

At 30-days, survival was similar between patients with or without new pacemakers, as well as for patients who had pacemakers prior to TAVI.

At one year, deaths were numerically higher among patients who had received a pacemaker than among those who didn't, but the difference was not statistically significant. "With both types of prosthesis, pacemaker implantation did not impact on early or mid-term survival," van Rothem concluded.

Some Unknowns

In the first few years of TAVI, pacemaker implantation with the CoreValve hovered around 25% and around 7% with the Sapien. Since then, operators have gradually reduced the number of pacemakers used in TAVI. During the Q&A session following the presentation, one audience member asked van Rothem if he had eased off on efforts to avoid a pacemaker, on the basis of these results.

In response, van Rothem noted that he and his colleagues are planning to continue following patients for longer-term outcomes and differences may yet emerge. They are also looking at differences in symptoms and subsequent heart failure according to need for pacemaker post-TAVI. "So I think it is important to avoid, as much as possible, the need for implanting a pacemaker," he said.

Dr John Webb (St Paul's Hospital, Vancouver, BC), one of the pioneers of transcatheter valves and comoderator of the session, noted that the topic is well-worth following in the years to come. "There may be a trend toward more adverse events as people try to avoid pacemaker use," Webb said. "We don't yet have an answer to these kinds of things."