SWEDEHEART Data Reassure on 10-Year Survival for TAVI Patients With Pacemakers

Implantation of a permanent pacemaker (PPM) in the 30 days after TAVI isn’t associated with worse long-term survival or higher risk of heart failure or endocarditis, according to a new analysis of the SWEDEHEART registry.

This does not mean that the need for a PPM—which affects 9% to 26% of TAVI patients—is entirely benign. “Implantation is associated with a risk of lead- and pocket-related complications and traumatic complications, longer hospital stays, and higher societal costs,” investigators caution.

For surgical aortic valve replacement, earlier research by the same group has shown PPM implantation predicts higher mortality, and other studies have linked PPM in TAVI to increased death risk, as well.

As such, the current results for transcatheter procedures are encouraging, senior author Natalie Glaser, MD, PhD (Karolinska Institutet, Stockholm, Sweden), told TCTMD in an email. “However, patients who undergo TAVR are older and have more comorbidities than patients who undergo SAVR, and it is likely that patients who undergo TAVR die of other causes before the negative effects of their pacemaker become clinically evident.”

Still, said Glaser, it seems that “when pacemakers are required because of severe conduction disturbances, they are doing their job well and should be implanted based on the recommendations by international guidelines.”

Tamim Nazif, MD (NewYork-Presbyterian/Columbia University Irving Medical Center, New York, NY), agreed with the takeaway that the results are reassuring. A strength is that they stem from a large, real-world data set from a region known for its comprehensive health records.

“But it’s not the final word,” Nazif commented to TCTMD, noting that the median follow-up was 2.7 years. “If you examine the numbers at risk, they really fall off at 5 years, even more so at 6 years. . . . So I think it’s challenging to make really ‘long-term’ conclusions based on this.” Details are missing on certain clinical factors, such as ECG findings that could reveal whether some patients without pacemakers might have had new-onset left bundle branch block that muddied patterns in adverse outcomes, he added.

What’s interesting, Nazif said, “is that people are looking at the lifetime management of these patients. A paper like this really is aimed at that: what happens at 5, 10 years down the road. And these are some of the first observations we’ve seen that far out. It’s not perfect, but I think it’s still very interesting.”

PPM rates with TAVI have been decreasing over the years, though there’s room for improvement and some say what’s been acceptable thus far may soon no longer be enough. Looking forward, there’s a salient question: as TAVI indications expand, how will pacemaker implantation affect the trajectory of younger, lower-risk patients?

“To treat [these] patients adequately, I think we need to aim for outcomes similar to surgery, [where] the pacemaker rates are roughly 5%. We need to aim to meet that bar. I think people are starting to understand that,” said Nazif.

SWEDEHEART Data

Glaser, along with Andreas Rück, MD, PhD, and Nawzad Saleh, MD, PhD (Karolinska Institutet), recently reported their results in JACC: Cardiovascular Interventions.

Between 2008 and 2018, a total of 3,420 patients (mean 81 years; 50% women) underwent transfemoral TAVI in the SWEDEHEART registry, with 14.1% subsequently receiving a PPM within 30 days. Individuals who got a PPM were less apt to be female, had higher prevalence of comorbidities (atrial fibrillation, diabetes, prior MI, and prior cardiac surgery), and were less likely to have initially been treated with balloon-expandable valves.

I think in a lower-risk population, pacemakers are going to have a more-detrimental impact, and of course that wasn’t examined in this study. Hemal Gada

Median follow-up was 2.7 years. Kaplan-Meier estimated survival was similar in the PPM and no-PPM groups at 1 year (90.0% vs 92.7%), 5 years (52.7% vs 53.8%), and 10 years (10.9% vs 15.3%; P = 0.692). There also were no differences in the risks of cardiovascular death, heart failure, or endocarditis. Consistent results were seen in propensity-matched analyses.

Despite the reassuring findings, Glaser remains convinced that PPM implantation should be avoided. “It is essential to develop newer-generation bioprostheses to minimize the risk for conduction disturbances and the need for permanent pacemaker implantation after TAVR,” she advised, adding, “Furthermore, the indications for permanent pacemaker implantation after TAVR have to be well balanced to implant permanent pacemakers only in patients who will really benefit from the therapy.”

Quality of Life and Other Consequences

Hemal Gada, MD (UPMC Pinnacle, Harrisburg, PA), also commenting on the Swedish data for TCTMD, emphasized that these are observational data spanning a mix of valve types and pacing scenarios, which could explain why outcomes here differ from previous less-reassuring reports. It may be that death rates with PPM are valve dependent, he suggested, or because patients in Europe are hospitalized longer than in the United States. Nor is it clear whether all the PPM implantations here were guideline-based.

Mortality hinges on many factors that are hard to capture, said Gada, among them “how the patient is managed, what type of patient it was, what the nature of the conduction disturbance was that led them to needing the pacemaker.”

For him, though, the largest consequence of PPM is impaired quality of life. “And of course that wasn’t really closely examined in this study,” he noted, adding, “It’s [usually] not a life-and-death type of thing, it’s how good your life is after your TAVR if you got a pacemaker versus didn’t.”

Beyond this, there’s the potential for complications, such as lead perforation and infection, when implanting the PPM, as well as the ongoing need for generator changes and added costs related to longer hospitalization and the PPM itself.

On top of TAVI, Gada stressed, “it’s an additional implant, and with an additional implant comes additional risk.”

PPM Impact ‘Remains Controversial’

Like Gada and Nazif, editorialists Antonio J. Muñoz-García, MD, PhD, and Erika Muñoz-García, MD (University Hospital Virgen de la Victoria, Málaga, Spain), say multiple confounding factors could explain why the Swedish data diverge from other, less-rosy reports. Specifics are missing on the heterogeneity of patients, the mix of prophylactic versus absolute indications for PPM, and basal LVEF, for instance.

“To date, the impact of permanent pacemaker implantation on late clinical outcomes after TAVR remains controversial; however, this study to some extent helps clarify this controversy. But to solve this lack of consensus, it is necessary to reduce the rate of [PPM], homogenize criteria and studies, and have long-term clinical follow-up,” they write, pointing to a 2019 expert consensus on the management of conduction disturbances as a useful “working tool” for clinicians.

As for TAVI’s growth into younger and lower-risk populations, Glaser noted that these “patients with a long life expectancy have a longer time to develop complications after TAVR compared to older patients with high surgical risk,” opening up the possibility that more negative effects of PPM will be seen. But, she said, additional studies are needed to compare their risks with the present findings.

Gada agreed that the long-term perspective is key. “I think in a lower-risk population, pacemakers are going to have a more-detrimental impact, and of course that wasn’t examined in this study,” he said.