By Jonathan Springston, Editor, Relias Media

The FDA has approved an expanded indication for four transcatheter heart valves to include patients who are at low risk for major complications or death associated with valve replacement surgery.

Previously, the indication for these products was for patients at intermediate and high risks of death or serious complications during open heart surgery. The FDA says it is the first medical products regulatory agency in the world to approve such an expansion.

“This new approval significantly expands the number of patients who can be treated with this less invasive procedure for aortic valve replacement and follows a thorough review of data demonstrating these devices are safe and effective for this larger population,” Bram Zuckerman, MD, director of the Office of Cardiovascular Devices in the FDA’s Center for Devices and Radiological Health, said in a statement.

Earlier this year, during the American College of Cardiology Annual Scientific Session and Expo, researchers presented findings from two key studies: PARTNER 3 and EVOLUT. In both studies, the authors compared the outcomes of transcatheter aortic valve replacement (TAVR) with those of surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis and a low risk of death with surgery. In both studies, TAVR outcomes were at least as good as if not better than SAVR for patients with severe aortic stenosis at low surgical risk.

These promising results played a role in the FDA’s decision. Still, the agency cautions the four transcatheter heart valves should not be used in patients who cannot tolerate blood thinning drugs or in those with active infections. Further, the FDA is requiring manufacturers to continue following patients enrolled in their randomized studies for 10 years to monitor transcatheter aortic valve safety and effectiveness, including long-term product durability.

"The treatment paradigm for aortic stenosis has evolved from a discussion about risk of surgery to one where anatomy really will dictate the choice between TAVR and SAVR," American College of Cardiology Surgeons' Council member Joseph Cleveland, MD, FACC, said in a statement after the FDA announced its decision. "For most patients, the preferred treatment will be TAVR, unless specific conditions like concomitant multivessel coronary artery disease, the presence of an aortic aneurysm, or aortic root anatomy, which is not suitable for a TAVR, exist.”

In the March 2019 issue of Clinical Cardiology Alert, Jeffrey Zimmet, MD, PhD, wrote about a large-scale retrospective analysis of all balloon-expandable TAVR valves, which revealed no apparent relationship between procedure volume and outcomes after an initial learning curve of 200 procedures. In his commentary, Zimmet noted the “constellation of changes that have improved [TAVR] safety.”

“These include moves toward more transfemoral access and more conscious sedation, the establishment of specialized structural heart training programs, and intensive industry-sponsored proctorships. Movement of TAVR to the mainstream has promoted discussion of techniques and best practices, with effective knowledge transfer from more-experienced to less-experienced operators and hospitals. Improvements in the devices themselves likely play an important but less significant role,” Zimmet wrote. “As TAVR evolves, the results of this study suggest that focusing on simple volume metrics as a surrogate for quality is likely to be misleading and may unnecessarily limit access.”

For more on this development and all the critical analysis of the latest clinical research cardiovascular medicine, please read the newest issues of Clinical Cardiology Alert.