麻豆传媒

WASHINGTON -- Among the bioprostheses used in aortic valve replacement, trancatheter ones were not necessarily more prone to the kind of valve deterioration that can result in poor clinical outcomes, according to a pooling of the CoreValve U.S. Pivotal and SURTAVI trials.

In fact, compared with surgical bioprostheses, the self-expanding CoreValve transcatheter aortic valve replacement (TAVR) devices were associated with a lower cumulative incidence of hemodynamic structural valve deterioration (SVD) manifesting as high gradients or aortic regurgitation at 5 years:

• Overall SVD: 2.57% vs 4.38% (P=0.0095)
• SVD in smaller annuli (annular diameter ≤23 mm): 1.39% vs 5.86% (P=0.049)
• SVD in larger annuli (annular diameter >23 mm): 2.48% vs 3.96% (P=0.067)

In turn, people with SVD tended to be the ones at greater risk of death (HR 1.98, 95% CI 1.42-2.76) and hospitalization for aortic disease or worsening heart failure (HR 2.11, 95% CI 1.19-3.74), reported Michael Reardon, MD, of Houston Methodist, at the American College of Cardiology (ACC) meeting.

This makes the CoreValve Evolut pooled analysis the first study to validate clinical criteria for SVD and its association with clinical outcomes, Reardon said.

Even so, what clinicians are really waiting for is the 10-year follow-up: long-term valve durability is an important issue given the recent expansion of TAVR to lower-risk people with severe aortic stenosis, including younger patients with longer life expectancies.

While the present study may not fully address the question of TAVR's durability, it does enhance the discussion of how it compares against surgical aortic valve replacement, suggested Megan Coylewright, MD, MPH, of Erlanger Health System in Chattanooga, Tennessee, at an ACC press conference.

"All of the data we have so far in both [self-expanding and balloon-expandable] platforms show that TAVR valves are lasting as long as surgery," she said.

There should be much heart team discussion regarding the first device recommended to a young person who may face two aortic valve replacements in a lifetime, said ACC discussant James McClurken, MD, of Doylestown Health in Pennsylvania.

"You don't want a third time, at [age] 82, which becomes an extremely complicated operation," he said.

Reardon noted that SVD is "something that accelerates with time" and predicted that the difference between TAVR and surgery will only grow larger by the 10-year mark.

Nevertheless, there is "no question" that mechanical surgical valves ultimately last longer and can be linked with a survival advantage in people ages 55 and younger, he acknowledged, adding that valve-sparing aortic root replacement and Ross procedures will also better preserve lifespan.

The CoreValve pooled analysis included people spanning intermediate-to-extreme surgical risk who underwent surgery or TAVR. Mean age was roughly 81, and over half of study participants were men.

Predictors of SVD included lower age and greater body surface area. Prior percutaneous coronary intervention, atrial fibrillation, and male sex were negative predictors of SVD.

Across the board, SVD largely took the form of aortic stenosis. There were very few cases of aortic regurgitation in the CoreValve studies.

Additionally, TAVR was associated with reduced moderate and severe SVD alike.

Reardon highlighted the value of serial Doppler transthoracic echocardiography to monitor valve function after TAVR. While studies in the current analysis lacked complete data on Doppler velocity index, this has recently emerged as an especially useful metric, he stated.

During the ACC panel discussion Suzanne Baron, MD, MSc, of Lahey Hospital & Medical Center in Burlington, Massachusetts, said quality of life and cost-effectiveness were areas to explore further in TAVR.

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