More Research Needed on Durability of Surgical Aortic Valves, More Researchers Warn

Researchers with the Cleveland Clinic and Mayo Clinic warn that there is not sufficient durability data on surgical aortic valves to determine whether they are safe over the long-term, amid growing concerns about the widespread use of devices to treat aortic stenosis. 

In a study published in this month in the medical journal JAMA Cardiology, researchers warn that there is inadequate long-term data on surgical valves used in surgical aortic valve replacement (SAVR) procedures.

Surgical aortic valve replacement is a form of open-heart surgery designed to replace the aortic valve in cases of aortic stenosis. In recent years, an alternative, less invasive, procedure known as transcatheter aortic valve replacement (TAVR) has increased in popularity, with proponents claiming it is safer and has a shorter recovery period. However, questions have been raised about the durability of TAVR valves, which were initially designed for older patients, and are being more and more commonly used on much younger patients. This has led to questions about the durability of the valves and whether they can last the life of the recipients.

This new study’s findings indicate that health care professionals and manufacturers do not know whether surgical aortic valves, which have been in use for much longer, are that durable either. That is making it harder to determine what standards and durability requirements for TAVR valves, being used in younger patients, should be.

Researchers looked at data on 167 studies, involving more than 101,000 patients and 17 different valves. The study looked for data on structural valve deterioration (SVD). However, researchers found follow-up ranges of less than a year to 14 years, and risks ranged from zero to 37 percent for patients.

“There is considerable variability in reporting SVD of surgical aortic valves, with different definitions and inadequate long-term systematically collected core laboratory data,” the researchers concluded. “Rigorously collected long-term data with standardized definitions for surgical values are needed to provide a benchmark for the durability of rapidly evolving transcatheter valves.”

The study’s findings come just days after a report by the International Consortium of Investigative Journalists (ICIJ), which found that there probably should be concerns about TAVR procedures.

Doctors stress that the artificial valves most certainly save lives. They are also highly attractive because the valves are implanted through non-invasive surgery, which usually implies less health risks and a shorter recovery time.

However, with their original design being for older patients, and their relatively new popularity, the artificial heart valves have not been on the market long enough for people to know how long they’ll function in patients. Doctors say they are currently making decisions about whether to recommend TAVR procedures over risky open-heart surgery without good data on long-term risks for younger patients.

Manufacturers are still researching the data, but time needs to go by to see how the recipients are doing. TAVR valves were first approved in 2007. The devices were first approved in Europe, which ICIJ reporters found to be more lax in medical device approval than the FDA in the United States.

Since 2007, more than 350,000 patients have undergone TAVR procedures.