Medtronic's CoreValve TAVR System Shows Lower Structural Valve Deterioration Versus SAVR

April 4, 2022—Michael J. Reardon, MD, presented a study, “Five-year Incidence, Timing and Predictors of Hemodynamic Valve Deterioration of Transcatheter and Surgical Aortic Bioprostheses: Insights from the Core Valve United States Pivotal and SURTAVI Trials," at ACC.22, the American College of Cardiology (ACC) 71st annual scientific session, held April 2-4 in Washington, DC.

According to the press release from ACC, the study showed that patients who received a transcatheter supra-annular self-expanding heart valve had significantly less structural deterioration in the valve after 5 years compared with similar patients who had the biologic valve inserted surgically. Overall, patients with structural valve deterioration (SVD) in their artificial valve were approximately twice as likely to die or need to be rehospitalized as those who did not.

Dr. Reardon reported that the study met its primary endpoint, with the incidence of SVD significantly lower in patients who received transcatheter aortic valve replacement (TAVR) than in those who received surgical aortic valve replacement (SAVR).

The study was funded by Medtronic, the manufacturer of the CoreValve TAVR device. Dr. Reardon, who serves as the study’s senior investigator, is Professor of Cardiothoracic Surgery and Allison Family Distinguished Chair of Cardiovascular Research at Houston Methodist DeBakey Heart and Vascular Center in Houston, Texas.

As noted in the ACC press release, TAVR is now approved by the FDA for use in patients of all ages and risk levels who need a replacement heart valve. “However, heart surgeons tend to worry that in younger, lower-risk patients, replacement valves inserted using TAVR may fail more quickly than surgically inserted valves,” advised Dr. Reardon. “The results of this study suggest exactly the opposite—that at 5 years, the TAVR-inserted valve has less structural deterioration than the surgically inserted one.”

The ACC press release stated that the study is the largest to assess SVD in patients who participated in randomized trials comparing TAVR and SAVR and the first to show less structural valve deterioration after 5 years among patients treated with TAVR compared with SAVR, Reardon said. Bioprosthetic valves have an average lifespan of about 15 years.

Dr. Reardon stated that valve durability has been less of a concern in older patients whose life expectancy may be limited by age and other health problems. Previous studies suggest, however, that younger patients are at higher risk for SVD because their valves fail more quickly and because they have a longer potential life span. Previous studies have not clearly established whether the risk of SVD is higher with TAVR or with SAVR. “Durability of the replacement valve becomes increasingly important in younger patients,” advised Dr. Reardon.

In the current study, the investigators analyzed data from 1,128 patients who underwent TAVR and 971 patients who underwent SAVR in two large, randomized trials to determine the frequency of SVD at 5 years. They evaluated SVD using Doppler echocardiography. Additionally, the investigators examined the factors that predicted deterioration in the same patient cohort plus an additional 2,663 patients who were treated with TAVR in a nonrandomized registry of the two trials.

The investigators found that 2.6% of the patients treated with TAVR had SVD at 5 years compared with 4.4% of patients treated with SAVR. Patients in both groups who developed SVD were at an approximately 50% greater risk of death or hospitalization for valve-related disease or heart failure as patients who did not have SVD.

Dr. Reardon stated, “Using Doppler echocardiography alone, we have shown that SVD occurred statistically significantly more frequently with SAVR than with TAVR and was associated with a doubling of risk for mortality or rehospitalization for valve failure.”

The most important predictors for developing SVD were being heavy or overweight, younger age, female gender, and not having previous coronary interventions or atrial fibrillation, observed Dr. Reardon.

The current study is limited to 5 years of follow-up. Establishing durability of the valves over a longer period of time remains important. Patients in two ongoing trials, SURTAVI for intermediate risk and Evolut for low risk, will each be followed for 10 years to help answer this question, noted the ACC press release.