麻豆传媒

CHICAGO -- Compared with surgery, transcatheter aortic valve replacement (TAVR) was associated with better outcomes in certain situations among low-risk patients, albeit an increase in pacemakers and paravalvular leaks, two meta-analyses showed.

Low-risk patients (with the Society of Thoracic Surgeons risk under 4%) who had severe aortic stenosis treated with TAVR instead of surgical aortic valve replacement (SAVR) had some reductions in adverse outcomes at 1 year, according to Aaqib Malik, MD, MPH, of Westchester Medical Center in Valhalla, New York:

• All-cause mortality: 2.1% vs 3.5% (RR 0.61, 95% CI 0.39-0.96); NNT=71

• Cardiovascular mortality 1.6% vs 3.0% (RR 0.55, 95% CI 0.33-0.90); NNT=74

• Atrial fibrillation: 10.0% vs 39.4% (RR 0.27, 95% CI 0.20-0.35); NNT=3

But favoring SAVR were pacemaker implantation rates (17.5% vs 5.4%, RR 3.96, 95% CI 1.65-9.54; NNH=8) and moderate-to-severe paravalvular leaks (2.9% vs 0.4%, RR 5.70, 95% CI 1.73-18.79), Malik told the audience here during a poster session at the Transcatheter Valve Therapy (TVT) meeting organized by the Cardiovascular Research Foundation.

The meta-analysis included four trials: this year's PARTNER 3 and Evolut Low Risk, 2018's SURTAVI, and from 2015.

Non-significant trends toward benefit found for TAVR were observed in:

• Stroke: 2.9% vs 4.2% (RR 0.68, 95% CI 0.43-1.07)

• Myocardial infarction: 1.7% vs 2.1% (RR 0.78, 95% CI 0.46-1.34)

• Major or life-threatening bleeds: 3.9% vs 14.0% (RR 0.37, 95% CI 0.12-1.12)

On the other hand, there were numerically fewer major vessel complications with surgery (3.2% vs 2.3%, RR 1.31, 95% CI 0.82-2.09), Malik's group found.

"[TAVR] is a paradigm shift -- a revolution -- for the vast majority of patients with symptomatic severe tricuspid AS [aortic stenosis]," Alexandra Lansky, MD, of Yale University School of Medicine in New Haven, Connecticut, told 麻豆传媒 via email.

"These benefits now convincingly extend to lower-risk patients, where we are now seeing consistent benefit in most serious complications as these two meta-analyses demonstrate significant reductions in mortality, stroke, bleeding, and atrial fibrillation," she said. "Not only is this a safer approach for patients at 1 year, but it will translate in a more cost-effective approach compared to surgery."

Lansky predicted that most low-risk patients will choose TAVR over SAVR despite the risk of getting a pacemaker or having "a little more leak around the valve."

One caveat of the meta-analysis is that NOTION involved the older-generation CoreValve, so the data may not be generalizable to current practice. Moreover, the authors included the low-risk subgroup of SURTAVI, and were limited to trial-level data for their analyses, Malik acknowledged.

A separate meta-analysis, also presented at TVT, included the same four studies and came out with nearly identical results that may be even more favorable for transcatheter therapy.

In addition to the aforementioned findings, Dhaval Kolte, MD, PhD, of Massachusetts General Hospital in Boston, told the audience that the TAVR arm also significantly benefited from lower rates of life-threatening or disabling bleeding (RR 0.37, 95% CI 0.24-0.55) and acute kidney injury stage 2 or 3 (RR 0.26, 95% CI 0.13-0.52).

"TAVR may be the preferred option over SAVR in low-risk patients with severe AS who are candidates for bioprosthetic AVR," Kolte concluded. "Long-term follow-up data on outcomes and valve durability remain critical."

After all, the major unknown is TAVR valve durability, Lansky noted, "though current available evidence suggests similar durability compared to surgical valves."