麻豆传媒

BOSTON -- Transcatheter aortic valve replacement (TAVR) in patients with small aortic annuli had better hemodynamic results with a self-expandable than a balloon-expandable valve, with suggestion of better clinical outcomes too, in the France-TAVI registry.

Mean gradient was significantly lower with self-expanding Medtronic CoreValve Evolut Pro or R devices at the end of the procedure and at 30 days and 1 year compared with balloon-expandable Edwards Sapien 3 valves, with differences of 3.98 to 5.12 mm Hg (all P<0.001).

Indexed effective orifice area was larger as well with the self-expanding valves at 1 year (1.11 vs 0.9 cm²/m², P<0.001), reported Walid Ben-Ali, MD, PhD, of the Montreal Heart Institute, at the Transcatheter Cardiovascular Therapeutics (TCT) meeting hosted by the Cardiovascular Research Foundation.

The significantly lower rate of moderate or severe patient-prosthesis mismatch (PPM) at 1 year with the self-expanding valves -- 11.3% vs 29.4% and 3.0% vs 8.5%, respectively -- was linked with mortality. Getting a balloon-expandable valve predicted 2.94-fold higher likelihood of moderate to severe PPM overall.

Severe PPM at 1 year predicted two-fold higher risk of death from any cause at 3 years independent of comorbidities in matched patients in the cohort (P=0.04).

"So here we see there is an impact at 3 years," Ben-Ali noted at a TCT press conference. However, he stated that for "clinical impact, we have to wait for a randomized trial to have a definitive conclusion," due to the retrospective design of the study, and shorter follow-up because of 30% loss of data at 5 years.

The was the first large, national, all-comer study comparing the two platforms in small aortic annuli TAVR patients.

The registry included 47,494 patients getting TAVR, among whom 19,204 had a small aortic annulus, defined as smaller than 23 mm diameter and indexed effective orifice area of less than 12 mm/m² on CT imaging.

The analysis focused on the 1,195 patients who got an Evolut R or Pro or Sapien 3 device, but results were similar in a matched cohort of 928 patients.

While a fairly large cohort, Ben-Ali reiterated that "We have a lot of limitations to the study design -- it's retrospective, 5% missing data, with multiple imputation. Let's wait for SMART trial to have a definitive conclusion."

The (SMART) is enrolling 700 patients to answer the same question in a more rigorous manner.

Ben-Ali said that as his group enrolls patients into SMART, "I'm seeing my patients treated with balloon-expandable [devices], the best one has 17 mm Hg gradients and the worst one in the self-expandable group has 9 mm Hg."

Press conference panelist Robert J. Cubeddu, MD, of Naples Heart Institute in Florida, agreed that it mirrors clinical impressions, although cautioning that the registry findings were not core lab adjudicated.

"I'm cautiously reassured about findings from this," added panelist Michael Young, MD, of Dartmouth Hitchcock Medical Center in Lebanon, New Hampshire. "In our practice, we're thinking about this very carefully. Our surgeons actually are very aggressive when they take patients for SAVR, surgical valve replacement, very aggressive about doing root enlargements in hopes of really small annuli getting larger surgical prosthetic valves. ... In our own practice, we sway toward supra-annular [self-expanding] design for patients."

And such biases could influence which patients get which device in a way that undermines registry data, if patients with coronary artery disease may be more likely to get a Sapien device to preserve access, for example, suggested session panelist Susheel K. Kodali, MD, of the Columbia University Irving Medical Center in New York City. He urged "real caution" in interpreting the findings.

While these patients feel better with lower gradients after TAVR, Young added, "we just don't know, one, the durability and, two, the clinical outcomes in the end."

The lifetime management perspective is important, he said. "That comes into the discourse in choosing TAVR versus SAVR at this point. Usually if the annulus is small we're also looking at the sinuses. And sometimes the sinuses will be very small too. You worry about sinus sequestration and boxing the patient in, so to speak, so in the next 5 to 10 years their coronary options will be limited."

While PPM may not be so important in very elderly patients, it is in younger patients, noted session panelist Bernard Prendergast, MD, of St. Thomas' Hospital and Cleveland Clinic London.

These data are a call to industry to think about patients with small annuli as it moves toward fourth and fifth generation devices, he said.

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