In replacement aortic valve procedures, bioprosthetic valves have become increasingly more common than mechanical replacements, since those made out of animal tissue are less likely to cause blood clots. In something of a trade-off, however, the bioprostheses are also more prone to deterioration over time, typically beginning about a decade after implantation.
But two of Abbott’s valves may be much less durable than that. In separate letters sent to healthcare providers on Monday, both the medtech giant and the FDA warned that the Trifecta family of bioprosthetic aortic valves may begin deteriorating within the first five years of implantation, potentially requiring earlier-than-expected replacement procedures or even leading to death.
The valve replacement portfolio—which Abbott acquired when it bought out St. Jude Medical in 2017—includes a pair of stented bovine pericardial valves, each featuring a trio of leaflets on the outside to help the valve stay open. The original Trifecta valve was approved by the FDA in 2011—though it’s no longer marketed in the U.S.—and a second-generation valve featuring “glide technology,” coined the Trifecta GT, was approved in 2016.
According to Abbott’s letter (PDF), though clinical studies comparing the Trifecta devices to other bioprosthetic aortic valve replacements showed that “most cases” of structural valve deterioration occurred after the first five years of implantation, with peak occurrence around the eight-year mark, those findings don’t align with real-world reports.
Instead, recent literature and user complaints both show a much higher incidence of valve deterioration within just a few years after a Trifecta device has been implanted. The literature review, for one, found that significantly more Trifecta users than those implanted with other valves require reintervention in both the short- and midterm—defined as occurring within the first five years and within six to 10 years of placement, respectively.
An analysis by Abbott of complaints received regarding the device showed that in real-world use, peak occurrence of structural valve deterioration is placed around the three- or four-year mark—compared to the year eight peak registered in the clinical trial data. The company’s analysis also found that the majority of the early deterioration cases center on a tear of at least one of the valve’s leaflets, while those reported after five years are caused by the calcification and hardening of the valve.
The FDA’s own notice to healthcare providers described the contents of some of the complaints that it received about the valves, including reports of unexpectedly early removal and replacement of the devices and, “in some cases,” death. The agency didn’t provide exact numbers of the reports that it has received to date, but reminded the letter’s recipients that, for the most part, the complaints sent to the agency are unconfirmed and can’t be definitively linked to a specific device issue without further investigation.
With the potential for early deterioration of the Trifecta valves, Abbott has asked healthcare providers to carefully weigh those potential harms against the benefits of even a short-term valve replacement.
Doctors should also perform an echocardiogram within a few months of the procedure to check on the implant’s progress, then schedule check-ups for every year after the implantation—with further scans performed as needed if patients develop any changes in symptoms that indicate the onset of structural valve deterioration.
Abbott and the FDA said they’re currently working together to “further evaluate the issue and develop additional patient management strategies, if needed,” per the regulator.