Latest Observational Data Support TAVR Durability Through 7 Years

Yet another data set is showing reassuring resilience for TAVR devices, this time using the new European criteria for bioprosthetic valve failure (BVF) and structural valve deterioration (SVD) that were released in late 2017.

By 7 years, the cumulative incidence of BVF in a multicenter French registry was 1.9%. Moderate SVD was seen in 7.0% of patients and severe SVD in 4.2%, respectively.

The researchers, led by Eric Durand, MD, PhD (Charles Nicolle Hospital, Rouen Cedex, France), stress that their ability to fully assess the long-term durability of TAVR was limited by the poor survival of their elderly, high-risk patient population.

As to whether transcatheter valves might match the durability of surgical bioprostheses over the long term, Durand told TCTMD: “I think it’s difficult to say that at the present. This is my point of view anyway: that the valve durability is the same.” Six-year data from NOTION, he noted, are promising in this regard and NOTION-2 may provide some answers on younger, lower-risk patients.

What can be said, Durand continued, is that for an elderly, high-risk population, “durability of transcatheter heart valves is not an issue, is not a problem.”

Rishi Puri, MD, PhD (Cleveland Clinic, OH), commenting on the latest findings, which were published online in Circulation: Cardiovascular Interventions, said the French study “certainly provides us with some more reassurance, although again numbers are small, most of these patients have died, [and] this really was the earliest experience with TAVI in the oldest, sickest patients.”

The overall message, though, is that by around 4 years “we are not seeing any alarm bells with transcatheter valves, because some of the preclinical testing . . . suggested that the transcatheter valves may be a little more fragile for a number of reasons—the way in which they are packaged, processed, crimped, ballooned, all these kinds of thing. There was certainly a lot of conjecture when we started doing these procedures that they may not last as long.”

We’ll have to wait for a long, long time to [hear] the results of long-term durability in lower-risk patients. Eric Durand

Use of standardized definitions is now helping to provide some clear comparisons between SAVR and TAVR, he added. “Surgical valves with modern-day definitions are not behaving anywhere near as well as what we thought they would, and they don’t seem to be behaving any differently from transcatheter valves and maybe they’re a little worse.”

For TAVR, though, there are few data beyond 7 years so the “jury is still out,” Puri observed. “We have to wait for the intermediate-risk patients to grow a bit older and hopefully survive. . . . I think it’s going to take a good 5 to 10 years for us to truly understand in large numbers across different valve types how these transcatheter valves are behaving.”

Trends in SVD by Valve Type

Durand and colleagues looked at 1,403 patients (mean age 82.6 years; 51.8% men) who underwent TAVR between April 2002 and December 2011 at five French centers. Mean logistic EuroSCORE was 21.3%. Most patients (83.7%) received a balloon-expandable valve, and the most common approach was femoral (65.4%).

Ultimately, 870 patients died during follow-up (median duration 3.9 years). Kaplan-Meier analysis estimated survival to be 18.6% at 7 years and 8.0% at 10 years. Five patients (1.0%) underwent reintervention by 7 years, one of which was surgical and the other four transcatheter.

SVD did not differ by valve type, though there was a trend toward higher incidence with balloon-expandable devices, both overall (12.2% vs 3.6%; P = 0.15) and individually for moderate and severe deterioration. The only independent predictor of SVD on multivariable analysis was valve size < 26 mm.

Even though the difference by device type was not statistically significant, that might have changed had more than approximately 15% of patients received self-expanding valves, Puri suggested.

Durand told TCTMD that this comparison was not part of their original paper, since the proportion of self-expanding valves was so small, but that the journal had requested that it be added before publication.

On the whole, Puri noted, “we are seeing some signals that are coming out to suggest that self-expanding valves may tend to fare a little better from a durability perspective compared to their balloon-expanding counterparts,” possibly due to differences in valve sizing and deployment between the two.

“I’m not saying that one valve is more durable than the other, but we’re starting to see some hints that are consistent,” he added. “So again, once we start to see the durability of a greater number of self-expanding valves out to a longer time period then we’ll be able to understand some of these differences a lot better.”

Puri also cautioned that the patients in this study are on the “other end of the spectrum” compared to those studied in the recent headline-grabbing low-risk TAVR trials presented at the American College of Cardiology 2019 Scientific Session. For the low-risk population, many of whom are younger, long-term follow-up is years away.

Durand agreed, pointing out that it’s been mere weeks since the PARTNER 3 and the Evolut TAVR in Low-Risk Patients trials were published. “We’ll have to wait for a long, long time to [hear] the results of long-term durability in lower-risk patients,” he stressed.