麻豆传媒

PARIS -- The valves used in transcatheter aortic valve replacement (TAVR, also known as TAVI) may not make it past 10 years, a study suggested.

Over long-term follow-up of at least 5 years, there was a 9.0% rate of degenerated heart valves. Two-thirds of these were associated with regurgitation, the rest related to stenosis.

The median time to valve degeneration was 61 months, although mean survival after TAVR was 51 months, , of St. Paul's Hospital in Vancouver, and colleagues reported in a late-breaking trial presentation at the EuroPCR meeting.

Freedom from transcatheter heart valve deterioration dropped to around 80% at year 6, then below 40% by year 8. Baseline renal failure was a risk factor for valve deterioration (hazard ratio 3.22, 95% CI 1.45-7.15).

"The risk for structural valve degeneration after TAVI should be considered, especially when treating relatively young patients and those at lower surgical risk." Dvir concluded. "Physicians must be mindful of limitations of the bioprostheses they implant and whether these valves can be safely/effectively treated by a transcatheter approach (valve-in-valve) if these valves fail years later."

Panelist , of Erasmus University Medical Center in Rotterdam, the Netherlands, told the audience that "maybe newer-generation valves will show better results. We don't know yet."

This was "a very early experience," said , of Houston Methodist DeBakey Heart & Vascular Center, in the same vein.

Dvir's study included 387 patients who underwent TAVR between 2002 and 2011 at two sites. Only two out of 387 patients (0.52%) survived 10 years after the intervention. Valve degeneration was defined as either moderate (or worse) aortic regurgitation or mean gradients greater than 20 mm Hg appearing after 30 days.

"Remember that early surgical tissue valves had very poor durability, but with better design and manufacturing the durability is now very good. TAVR valves are rapidly evolving and improving in design and construction," Reardon told 麻豆传媒.

But for now, long-term TAVR durability does not look promising. "Durability is the main remaining issue and generally this is the first paper where I have seen a significant signal for valve failure" that starts "sooner than what we see in surgical valves," Reardon said.

"From the surgical data," he noted, "we know that structural valve deterioration depends on the age of the patient and that the older you are, the slower the valve degenerates. These patients die faster also due to age, but the degeneration rate is independent of that. In this elderly population, we would hope that the signal would take even longer to show up and it did not."

"We know from surgical valve durability studies that 7 to 8 years is when you first see durability issues, so this isn't totally surprising and fits with some of the early thoughts/projections 10 years ago of TAVR durability," , of The Heart Hospital Baylor in Plano, Texas, told 麻豆传媒.

"We have to be careful before we move to lower-risk patients," said Kappetein.

"Durability has been and remains the major concern before wide adoption in younger patients," Mack agreed. "In a patient with a life expectancy of 5 to 7 years, TAVR is fine. We should be cautious before widespread adoption in patients with a life expectancy of more than 10 years."

TAVR trials in lower-risk patients will include 10-year follow-up, he noted.

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