Late outcomes of transcatheter aortic valve replacement (TAVR) in the PARTNER 2A trial are now enshrined in the peer-reviewed literature.

After 5 years, the trial shows comparable rates of the primary endpoint, death or disabling stroke, in older patients with severe, symptomatic aortic stenosis at intermediate surgical risk who underwent either TAVR or surgical aortic valve replacement (SAVR).

The findings, reported today in the New England Journal of Medicine but presented at a conference in October, suggest that the comparable, previously reported primary outcomes at 2 years in the patients receiving TAVR or SAVR have held over the long term. Despite the trial's use of a now-outmoded transcatheter valve, "in an era when the TAVR procedure was not yet refined to where it is today, the clinical outcomes of death, stroke, and quality of life measures and valve hemodynamics were similar between TAVR and surgery," lead author Raj R. Makkar, Cedars Sinai Medical Center, Los Angeles, California, told theheart.org | Medscape Cardiology.

The 5-year composite rate of disabling stroke or death from any cause, the primary endpoint, was 47.9% for the 1011 patients the TAVR group and 43.4% for the 1021 assigned to SAVR (hazard ratio [HR], 1.09; 95% confidence interval [CI], 0.95 - 1.25, P = .21).

The mean age in the trial was 81.6 and 45.5% of the patients were women.

The risk of the primary endpoint for the three fourths of patients who underwent TAVR with transfemoral access was not elevated compared with SAVR at 1.02 (95% CI, 0.87 - 1.20; P = .80), but was significantly increased at 1.32 (95% CI, 1.02 - 1.71; P = .03) in the remaining one fourth receiving TAVR by transthoracic access, a route that is now rarely used.

Makkar observed that at his center, perhaps 95% of TAVRs are transfemoral and the rest are via large arteries other than the femoral; thus, the transthoracic results likely don't have much relevance today.

 

The PARTNER 2A findings are mostly just reassuring at this point in the ascendance of TAVR as usually preferable compared with SAVR for patients with symptomatic aortic stenosis. They come after the TAVR frontier has already successfully extended into the much larger population of patients with aortic stenosis who are at low surgical risk based on trials like PARTNER 3 and Evolut.

Also, TAVR was also found comparable to SAVR in intermediate-risk patients in the SURTAVI trial, albeit using different prostheses. SURTAVI used primarily the first-generation CoreValve along with some Evolut R valves, both from Medtronic, whereas PARTNER 2A tested the now-outdated Sapien XT from Edwards Lifesciences, which has since been replaced by the company's SAPIEN 3 valve.

Of note, rates of reintervention in PARTNER 2A were 3.2% for TAVR patients compared with 0.8% for SAVR, low in both groups but significantly higher for TAVR.

Still, that didn't hurt survival for TAVR compared with SAVR. "When a reintervention was needed, most of the patients got a repeat TAVR, and they survived. When a reintervention was needed with surgery, it required repeat surgery and their mortality was in fact higher," Makkar said.

He attributes the greater TAVR reintervention rate to a higher rate of paravalvular leakage than after SAVR. Paravalvular aortic regurgitation that was mild or worse by echocardiography was seen in 33.3% and 6.3% of patients, respectively, over 5 years.

"I think the important lesson that we can take from here is that moderate and severe paravalvular leakage adversely affects outcomes and every attempt should be made to make sure that patients are not left with significant leaks," Makkar said.

And, he added, design changes in contemporary valves "have largely taken care of" the problem.

PARTNER 2A was funded by Edwards Lifesciences, from which Makkar discloses receiving research grants, personal fees, and travel support; he also discloses receiving grants and personal fees from Abbott, Boston Scientific, and Medtronic. Disclosures for the other authors are at NEJM.com.