First Long-Term Study of Valve Durability Shows High Rates of Degeneration

May 17, 2016—The first study investigating the long-term durability of transcatheter aortic valve replacement (TAVR) found that approximately 50% of transcatheter heart valves (THVs) may undergo degeneration within 10 years. The study was presented at the EuroPCR 2016 conference held May 17–20 in Paris, France.

In the EuroPCR announcement, the study’s lead investigator Danny Dvir, MD, commented, “TAVR is increasingly being performed in younger patients and in those at lower surgical risk. As a result, life expectancy after TAVR will increase. But the durability of these valves has been assessed only over the short and intermediate term.” Dr. Dvir is from the Center for Heart Valve Innovation at St Paul’s Hospital in Vancouver, British Columbia.

According to the EuroPCR announcement, the study investigators evaluated 704 patients (mean age, 82 years) who underwent TAVR between April 2002 and May 2011 at a center in Vancouver and one in Rouen, France. A total of 378 patients were followed with repeat echocardiographic examinations for up to 10 years. The study excluded patients who died within 30 days of TAVR, experienced device failure immediately after TAVR, and had valve-in-valve procedures. Implanted valves include the Edwards Sapien XT (36%), Edwards Sapien (50%), and Cribier-Edwards (14%) devices (all Edwards Lifesciences).

One hundred patients survived at least 5 years after TAVR. These patients were investigated for valve degeneration, which was defined using central lab–adjudicated criteria of moderate/severe intravalvular regurgitation and/or aortic stenosis (mean gradient > 20 mm Hg) that did not appear within 30 days of the TAVR procedure.

Over this time, the study identified 35 cases of valve degeneration. Approximately two-thirds of the failed valves were associated with intravalvular regurgitation, and the remaining one-third was associated with valvular stenosis. A few rare cases also showed a mixture of stenosis and regurgitation. The Kaplan-Meier estimate for the 8-year rate of structural valve degeneration was approximately 50%, reported the investigators.

Dr. Dvir noted that a significant number of valves showed degeneration between 5 and 7 years after TAVR.

In the EuroPCR press release, Dr. Dvir advised, “Physicians performing TAVR in younger patients and in those expected to survive long after the procedure should be aware that the long-term rate of THV degeneration is not negligible, at least for first-generation THV devices. Physicians must be mindful of the limitations of the THV they implant and whether patients can be safely treated by another transcatheter approach, such as valve-in-valve, if a THV fails years later.”

Commenting on the new findings, Pieter Kappetein, MD, from Erasmus Medical Center in Rotterdam, the Netherlands, added, “This is extremely important data and addresses the concerns that many people had when THV were introduced: Will they last as long as surgical bioprostheses? Can we therefore expand the indication to younger patient?” He continued, “Hopefully, the new generation of TAVR (devices) will last longer and there might also be a need for self- regenerating tissue-engineered heart valves.”

“Expansion of TAVR indication should only take place in the confines of a randomized trial,” concluded Dr. Kappetein in the EuroPCR announcement.