Is TAVR better than surgery for aortic stenosis patients?

Treatment with transcatheter aortic-valve replacement (TAVR) or surgery in low-risk patients with severe, symptomatic aortic stenosis results in similar and low clinical event rates at 5 years, according to the results of the PARTNER 3 study.

Differences in the rate of cardiovascular (CV) death, stroke, or CV rehospitalization, which were in favour of TAVR at 1 year, decreased after 5 years (∆, 7.1 percent to 4.3 percent). Additionally, improvements in patient-reported outcomes at 1 year persisted and were comparable for both TAVR and surgery. [Mack MJ, et al, TCT 2023]

“We can tell our patients who have low-risk aortic stenosis that for these two therapies, that by the end of 5 years, there’s more than a 70-percent chance they will be alive and feeling well with either no or very mild symptoms,” said co-author Martin Leon, MD, Columbia University Irving Medical Center, New York, US, in a news release for TCT 2023.

“We can also tell them that at the end of 5 years, there’s also a more than 85-percent chance with either therapy they’ll be alive with a durable heart valve based on BVF (bioprosthetic valve failure) assessment,” he added. [https://www.tctmd.com/news/some-surprises-low-risk-tavi-follow-partner-3-and-evolut-trials]

In PARTNER 3, Leon and his team randomized 1,000 patients with severe, symptomatic aortic stenosis and low surgical risk to undergo either TAVR (n=503) or surgery (n=497). They then evaluated the clinical, echocardiographic, and health-status outcomes through 5 years.

A composite of death, stroke, or rehospitalization related to the valve, the procedure, or heart failure served as the primary outcome. The secondary outcome, assessed using a win ratio analysis, was a hierarchical composite including death, disabling stroke, nondisabling stroke, and the number of rehospitalization days. [N Engl J Med 2023;doi:10.1056/NEJMoa2307447]

The primary outcome occurred in 111 of 496 patients who underwent TAVR and in 117 of 454 patients treated with surgery (Kaplan‒Meier estimates: 22.8 percent with TAVR and 27.2 percent with surgery; difference, ‒4.3 percent, 95 percent confidence interval [CI], ‒9.9 to 1.3; p=0.07). The win ratio for the secondary outcome was 1.17 (95 percent CI, 0.90‒1.51; p=0.25).

Mortality rate

The corresponding Kaplan‒Meier estimates for TAVR and surgery were 10.0 percent and 8.2 percent for death, 5.8 percent and 6.4 percent for stroke, and 13.7 percent and 17.4 percent for rehospitalization.

The haemodynamic performance of the valve was similar between the two therapies: 12.8 mm Hg in the TAVR group and 11.7 mm Hg in the surgery group. Finally, BVF occurrence was also comparable between the TAVR and surgery groups (3.3 percent vs 3.8 percent).

Follow-up data also revealed numerically higher deaths among TAVR patients than among those who underwent surgery. [https://www.tctmd.com/news/some-surprises-low-risk-tavi-follow-partner-3-and-evolut-trials]

“All-cause mortality [curves] did cross towards the middle of the follow-up,” Leon said in the news release. “First, all-cause mortality is both CV and non-CV, and there was a disproportionate amount of non-CV deaths in the TAVR arm versus surgery. If you look at CV mortality, the difference is 0.4 percent over 5 years. So, it’s mainly the non-CV deaths.”

In terms of clinical implications, the 5-year findings from PARTNER 3 confirmed the clinical and echocardiographic benefits of TAVR as an alternative to surgery for low-risk patients with severe, symptomatic aortic stenosis.