HEART & VASCULAR

TAVR Valves Demonstrate Superior Hemodynamics, Comparable Safety to Surgery, in 5-Year SURTAVI Trial

Aug. 26, 2022 - Eden McCleskey

Valves implanted during transcatheter aortic valve replacement (TAVR) surgery remain stable at five years, according to a new JAMA Cardiology study, an important finding as doctors try to determine which failing heart patients will best benefit from the minimally invasive procedure.

The results provide some of the first evidence on the longer term durability of valves used in TAVR, an increasingly popular option for patients with severe aortic stenosis. The valves’ durability lies at the heart of decisions on whether it should be recommended to younger patients.

“These positive five-year results get us that much closer to being able to answer the question of who’s right for TAVR,” says Dr. Michael Reardon, Houston Methodist cardiothoracic surgeon and the trial’s principal investigator. “This type of longer-term, randomized data is increasingly important as we strive to better understand the lifetime management of these patients.”

The results from Five-Year Incidence, Timing and Predictors of Hemodynamic Valve Deterioration of Transcatheter and Surgical Aortic Bioprostheses: Insights from the CoreValve U.S. Pivotal and SURTAVI Trials were first presented at the American College of Cardiology Annual Meeting in April 2022.

The research compares TAVR with surgical aortic valve replacement (SAVR), an open-heart surgery that involves stopping the heart to insert an artificial valve. With TAVR, the only incision is a small hole in the groin where a catheter is inserted.

In less than a decade, TAVR has evolved into a common treatment around the world for severe aortic stenosis, thanks in large part to two major series of clinical trials proving it to be a safe and effective alternative to SAVR.

But because the durability of the TAVR valves was unknown, surgeons weren’t sure whether to recommend the procedure to younger patients, who likely might need follow-up procedures.

The SURTAVI results showed that the hemodynamic benefits of the Medtronic CoreValve and Evolut platforms were maintained at five years with an excellent safety profile and stable valve performance in symptomatic patients with severe aortic stenosis who are at an intermediate risk for open-heart surgery.

All-cause mortality was similar between TAVR and SAVR (30.0% for TAVR versus 28.7% for SAVR; p=0.55), while rates of disabling stroke were also similar (4.1% for TAVR versus 5.8% for SAVR, p = 0.12). The TAVR valves continued to demonstrate durable longevity, with better mean aortic valve gradients (8.6 mm Hg vs. 11.2 mm Hg; p<0.001) at five years. Overall, these figures differed very little from those seen shortly after implantation. Additionally, valve thrombosis remained uncommon for both TAVR and SAVR groups.

Outcomes remain strong

TAVR’s initial benefits are obvious. As Dr. Reardon says, "No matter who you are, you're going to go home faster, recover faster and feel relief from the symptoms of aortic stenosis faster."

A question that remains is valve durability versus life expectancy, a concept that has been termed “lifetime management.” Ideally, the durability of a valve should outlast the life expectancy of the patient.

"TAVR was initially developed for patients who were deemed too frail to undergo surgery, and our initial high-risk trial had a mean patient age of 83," says Dr. Neal Kleiman, a Houston Methodist interventional cardiologist. "In that population, there wasn't as much concern about whether the valves would last 15, 20 years or more."

Over the course of the past decade, however, the encouraging safety profile reported in high-risk, intermediate-risk and low-risk clinical trials led to a progressive expansion of criteria so that surgical risk is no longer a determining factor.

“In these younger patients, we are now concerned about valve durability, and are also focusing on what other measures we can take to reduce long-term mortality in patients with aortic stenosis,” Dr. Kleiman says.

Current clinical guidelines recommend SAVR for patients younger than 65 or with a life expectancy of more than 20 years. For patients over age 80 or with a life expectancy of less than 10 years who are suitable for a transfemoral TAVR, TAVR is recommended. Between the ages of 65 and 80, the guidelines suggest balancing the risks of each along with the patient's wishes when making the choice.

Houston Methodist Hospital was the lead enrolling site in the CoreValve high-risk clinical trial, which has previously announced its five-year results. In the intermediate-risk (SURTAVI) and low-risk (Evolut Low Risk) clinical trials, Dr. Reardon served as principal investigator while Dr. Kleiman was a contributing author.