With the Food and Drug Administration’s approval of two different pairs of transcatheter aortic valve replacement systems for patients at low surgical risk, U.S. case volume for the procedure should markedly rise given that patients at low surgical risk form the largest risk subgroup among patients with aortic stenosis severe enough to warrant valve replacement.
But even as transcatheter aortic valve replacement (TAVR) now becomes the predominant approach for fixing severely stenotic aortic valves regardless of a patient’s risk level, the procedure remains less optimal than surgical aortic valve replacement (SAVR) in selected patients, putting an onus on clinicians to identify and alert patients for whom the transcatheter approach is questionable.
The anticipated surge in TAVR cases for low-risk patients after the FDA’s Aug. 16, 2019,will also likely lead to more hospitals offering TAVR. That development will test whether recently enacted from the Centers for Medicare & Medicaid Services on procedure-volume minimums for TAVR programs – at least 20 cases a year (or 40 within 2 years) at centers that also perform at least 300 percutaneous coronary interventions annually – lead to outcomes at lower-volume centers that come reasonably close to the outcomes at higher-volume programs for low-risk patients.
“The paradigm has definitely shifted from SAVR as the gold standard to TAVR as the primary treatment for aortic stenosis. This opens TAVR to the vast majority of patients with aortic stenosis,” roughly three-quarters of patients with aortic valve stenosis severe enough to need valve replacement, said, a cardiothoracic surgeon and professor of surgery at the University of Colorado at Denver, Aurora.
The actual, immediate increase in TAVR patients may not be quite as large as this fraction suggests. That’s in part because many patients in the low-risk category based on their surgical risk score already have been judged to have higher-risk features by heart-valve teams that has allowed such patients to undergo TAVR, said, professor of medicine and director of interventional cardiology at the University of Colorado.
For several years, U.S. rates of TAVR have exceeded SAVR, he noted, and in 2018 U.S. programs performed roughly 58,000 TAVR procedures and about 25,000 SAVRs, according to data collected by the Transcatheter Valve Therapy (TVT)run by the Society of Thoracic Surgeons and the American College of Cardiology. Dr. Carroll is vice chair of the steering committee for this registry, which was mandated by the FDA in 2011 when the agency first TAVR onto the U.S. market and is designed to capture every TAVR case performed in routine U.S. practice.
Despite this caveat, “there will be substantial growth in TAVR. Going forward, there will be more of a shift from SAVR to TAVR. That is what the results of the low-risk trials did,” Dr. Carroll predicted. In addition, the coming growth in TAVR numbers will stem from more than just low-risk patients whom a month ago would have undergone SAVR but now undergo TAVR instead. The availability of TAVR as an option for a wider range of patients should help boost public awareness that a nonsurgical way exists to treat severe aortic stenosis, plus the aging of baby boomers is on the verge of generating a substantial wave of new patients, a wave so high that Dr. Carroll called it a looming “tsunami” of patients needing TAVR.