Data from the SMART trial—in which it was shown that a self-expanding transcatheter aortic valve implantation (TAVI) system exhibited superior valve performance at one year to a balloon-expandable valve in patients with small aortic annuli—may influence valve choice in female patients, Roxana Mehran (Mount Sinai Hospital, New York, USA) told delegates at EuroPCR 2024 (13–17 May, Paris, France).
Mehran presented outcomes from a sub-analysis focused on the 637 female patients enrolled in the trial who made up 87% of the trial’s overall population during a late-breaking trial session on day one of the EuroPCR congress.
The randomised trial compared the supra-annular self-expanding Evolut (Medtronic) family of TAVI valves against the balloon-expandable Sapien 3 and Sapien 3 Ultra devices, and was the first trial to focus specifically on TAVI device choice and outcomes in small annuli. Women, who have historically been underrepresented in TAVI device trials, make up a large majority of the overall population of patients with small annuli.
Headline 12-month results of the trial, shared to wide interest at the American College of Cardiology (ACC) 2024 scientific session (6–8 April, Atlanta, USA), showed that there was no significant difference in the primary clinical endpoint between groups in terms of a composite of death, disabling stroke or rehospitalisation for heart failure. The Evolut system showed a 32.2 percentage point advantage in the self-expanding platform in terms of bioprosthetic valve dysfunction.
Mehran’s presentation at EuroPCR zeroed in on the 307 female patients who underwent TAVI using Evolut, and the 313 who received Sapien, also looking at findings out to 12 months.
Mehran reported that the clinical composite outcome of death, disabling stroke or heart failure rehospitalisations through 12 months was similar between the two groups, with an absolute difference of 2.3% in favour of the Evolut platform.
Turning to bioprosthetic valve dysfunction, an endpoint powered for superiority, Mehran described the difference as “dramatic”, with a 33.4% difference in favour of the Evolut platform.
For haemodynamic measures, including effective orifice area and mean gradient through 12 months, Mehran reported that these both favoured Evolut, whilst aortic regurgitation, observed as moderate or mild-to-moderate, was noted in 12.3% of patients treated with Evolut and 18.8% treated with Sapien.
“Ladies and gentlemen, SMART is a historic trial, [it is] the only randomised clinical trial enrolling 90% women with aortic stenosis and a small annulus,” Mehran said, acknowledging that such trials in a largely female population are long overdue.
Summing up the key findings of the trial as relating to female patients, she commented: “Through one year, the clinical composite outcomes of death, disabling stroke or heart failure rehospitalisation are similar amongst women with aortic stenosis and a small annulus randomised to Sapien or Evolut.
“But, compared to the balloon-expandable Sapien valve, the Evolut self-expanding valve was associated with significantly less bioprosthetic valve dysfunction, less prosthesis patient mismatch, less total aortic regurgitation and [greater improvement in] quality of life in women with aortic stenosis and a small annulus.”
Discussing the findings following her presentation, Thomas Modine (CHU de Bordeaux, Bordeaux, France) asked Mehran if, in light of the SMART trial, all women undergoing TAVI should be treated using self-expanding devices.
“It’s a really good question,” she responded. “At this timepoint, from what I have seen and what we have shown, absolutely, a woman with a small annulus, I think we have definitive answers.”
Pressed on this, Mehran said it is important to weigh up pathobiological differences in how aortic stenosis affects the sexes, including the presence of calcification and remodelling.
“The truth is, what we have here is definitive evidence that perhaps a supra-annular valve that gives you a larger effective orifice area and better haemodynamics may lead—and there is no difference in the clinical outcomes at all at the moment—but this may lead to a better outcome and perhaps it would be a better platform for women,” Mehran speculated.
