PARTNER 3: TAVR Associated with Significant Reduction in One-year Death, Stroke

Transcatheter aortic valve replacement (TAVR) with a SAPIEN 3 valve was associated with a 46% reduction in mortality, stroke and rehospitalizations in one year compared to surgery in patients with severe aortic stenosis, according to new study results presented at the American College of Cardiology Annual Scientific Sessions in New Orleans.

Researchers for the PARTNER 3 trial, led by Martin Leon, MD, of Columbia University Irving Medical Center/New York Presbyterian Hospital, randomly assigned 1,000 patients with severe aortic stenosis (1:1) to undergo either TAVR with the SAPIEN 3 valve. The primary study endpoint was a composite of all-cause death, any stroke, or rehospitalization after one year. Patients were enrolled across 71 centers, with a mean age of 73 years.

According to the results, the Kaplan-Meier estimate of the risk of death, stroke, or rehospitalization at one year was lower in the TAVR group than the surgical cohort (8.5% vs. 15.1%, respectively; absolute difference, -6.6%; 95% CI, -10.8 to -2.5; P<0.001 for noninferiority; P=0.001 for superiority). TAVR at 30 days was also associated with lower rates of stroke than with surgery (P=0.02), rates of death or stroke (P=0.01), and lower rates of new-onset atrial fibrillation (P<0.001). Patients in the TAVR cohort also had shorter index hospitalization compared to surgical patients (P<0.001), as well as a reduced risk for poor treatment outcome at 30 days (P<0.001). Vascular complications were similar between study groups, severe paravalvular regurgitation, or new permanent pacemaker insertions.

Landmark Result

“This is a landmark study because it involves 80% of the people who are currently being treated with surgery for aortic stenosis,” Dr. Leon said in a press release. “Our hope was that TAVR would be non-inferior or comparable to surgery, and we were surprised to find an almost 50% reduction in the primary endpoint […] with TAVR. This is beyond anything we could have expected, mostly because surgery is so good in treating aortic stenosis in these low risk patients.”

In his meeting presentation, Dr. Leon expounded on the potential clinical implications of the PARTNER 3 results.

“Based upon these findings, TAVR, through one year, should be considered the preferred therapy in low surgical risk aortic stenosis patients,” Dr. Leon commented in his presentation. “The choice of TAVR versus surgery in aortic stenosis patients should be a shared decision-making process, respecting the patient preferences, understanding knowledge caps (especially in younger patients), and considering clinical and anatomic factors.”

He did list some of the study limitations as well, which included a lack of long-term assessment (although a 10-year clinical and echocardiographic follow-up is planned for all patients), and also that the results are limited to the aortic stenosis patient population.

The full manuscript was simultaneously published in the New England Journal of Medicine.