Newest Sapien TAVI Equals Surgery in Patients With Small Aortic Annuli at 5 Years

LONDON, ENGLAND—Having a small or large annuli does not appear to make a difference for low-risk patients with symptomatic severe aortic stenosis, who have similar 5-year clinical and quality-of-life outcomes with either balloon-expandable TAVI or surgery, a new PARTNER 3 analysis shows.

The need for aortic valve reintervention also was similar between those treated with TAVI and surgery irrespective of annulus size, reported investigators this week at PCR London Valves 2024.

“The primary composite endpoint of all-cause death, stroke, and valve-related or procedure-related rehospitalization was numerically lower in the small-annuli group that received TAVI,” lead investigator Mahesh Madhavan, MD (Columbia University Irving Medical Center/NewYork-Presbyterian, New York, NY), told TCTMD. “That didn’t reach statistical significance, but you know, I think it’s reassuring to say if you have a small aortic annulus and you get TAVI, the outcomes are quite comparable to surgery.”

The results, he said, provide some insight on clinical outcomes, as opposed to just hemodynamics, in patients with a small aortic annulus.

The SMART trial, a dedicated study of patients with a small aortic annulus presented earlier this year, appeared to give an edge to self-expanding devices over balloon-expandable devices at 1 year. Patients treated with a balloon-expandable valve (Sapien 3/3 Ultra; Edwards Lifesciences) had higher mean gradients, higher prothesis-patient mismatch (PPM), and higher overall rates of hemodynamic structural valve dysfunction (BVD) at 12 months as compared with those treated with a self-expandable valve (Evolut PRO/PRO+/FX; Medtronic).

When he presented the results, lead SMART investigator Howard Herrmann, MD (Perelman School of Medicine at the University of Pennsylvania, Philadelphia), said he believes the higher rate of BVD with the balloon-expandable valve will translate into worse clinical outcomes over time.

“Our focus here is to understand how patients do clinically by annulus size,” said Madhavan. “Right now, we only have 1-year data from SMART. We wanted to provide some longer-term clinical insights.”

The other relevant dataset here is RHEIA, the all-female trial comparing balloon-expandable TAVI and surgery for symptomatic severe aortic stenosis, presented at the European Society of Cardiology Congress in August. That trial suggested that women, who typically have smaller annuli, fared better with transcatheter versus surgical replacement, a difference driven by fewer rehospitalizations.

Outcomes Similar at 5 Years

Madhavan’s presentation focused on 925 patients with CT-derived annular data in the PARTNER 3 randomized trial of TAVI versus surgery in low-risk patients. In total, 293 patients had a small aortic annulus, defined as ≤ 430 mm², while the remainder had a large annulus. For those with a small annulus, 155 were treated with TAVI and 138 underwent surgical valve replacement. In the large annulus group, 330 were treated with TAVI and 302 underwent surgery. 

In the small-annuli cohort, the primary endpoint of death, stroke, or rehospitalization at 5 years occurred in 21.2% of those treated with TAVI and 31.6% of those treated with surgery, a numerical but nonsignificant difference (P = 0.06). In the large-annuli group, the rates were 23.5% with TAVI and 25.5% with surgery (P = 0.33).

There was no difference in the risk of bioprosthetic valve failure or need for aortic valve reintervention between TAVI and surgery in both the small- and large-annuli subgroups. Quality of life was similar in TAVI-treated and surgical patients irrespective of annular size.

I think it’s reassuring to say if you have a small aortic annulus and you get TAVI, the outcomes are quite comparable to surgery. Mahesh Madhavan

Tom Cahill, MD (Oxford University Hospitals, England), one of the panelists during the featured research session, said operators are increasingly thinking about how best to treat patients with small annuli, the vast majority of whom are women.  

While these data are reassuring, he said, follow-up at 5 years is not long enough to fully understand durability issues that may arise with worsened early hemodynamics. Operators would still like to know if there is a type of patient with small annuli in whom they should be concerned about PPM or risk of early valve dysfunction, said Cahill.

Patrick Serruys, MD, PhD (University of Galway, Ireland), asked the PARTNER 3 group if the effective orifice area (EOA) was equivalent after TAVI and surgery and if it had any impact on clinical outcomes.

In response, Madhavan said they have not yet looked at 5-year outcomes stratified by PPM or EOA. Regarding PPM, he said there are some data in low- and intermediate-risk patients suggesting it is not associated with worse outcomes, but the evidence is limited and should be considered hypothesis-generating.

In terms of choosing the best treatment for patients with symptomatic severe aortic stenosis and small annuli, surgery is a strong consideration in low-risk patients, Madhavan told TCTMD. However, these data don’t show any risks associated with TAVI using the Sapien balloon-expandable device when compared with surgery, he said.

“Clinically, with a study like this, we can be confident that we’re in the right patient and can expect similar outcomes regardless of annulus size between TAVI and surgery,” said Madhavan. “That’s consistent with the larger findings—the outcomes are similar, at least up to intermediate follow-up.”  

Sapien Ultra Resilia

The question of which type of TAVI device might be better suited to small annuli remains an active debate, particularly since SMART tested the self-expanding Evolut PRO/PRO+/FX valve against the “older” Sapien 3/3 Ultra. 

In a separate presentation at London Valves, Hirofumi Hioki, MD (Teikyo University Hospital, Tokyo, Japan), reported data from OCEAN-TAVI to see how Ultra Resilia fared against the self-expanding Evolut FX valve in patients with small aortic annuli. Hioki said there are data showing the newer Sapien valve outperforms the older-generation Sapien 3, with lower rates of paravalvular leak and PPM, as well as a lower prevalence of mean pressure gradients exceeding 20 mm Hg.

The study, published simultaneously in JACC: Cardiovascular Interventions, included 1,227 patients who underwent TAVI as part of the trial and showed that valve hemodynamics remain better with Evolut FX compared with the fifth-generation Sapien Ultra Resilia valve in patients with small aortic annuli, although the gap between valves is closing.

In a propensity-matched analysis comparing patients treated with Sapien Ultra Resilia with those treated with Evolut FX, severe PPM was numerically, but not significantly, increased in patients treated with Resilia. Additionally, there was a significantly increased risk of elevated postprocedure mean pressure gradients (≥ 20 mm Hg). Rates of mild or greater paravalvular leak (PVL) and need for new permanent pacemaker were lower with Resilia, however.

Despite better hemodynamics with Evolut FX, the Resilia device has clearly improved over Sapien 3, Hioki noted. Against an historical control group of patients treated with the older device, severe PPM declined with Resilia, as did the number of patients with mean gradients ≥ 20 mm Hg. Rates of PVL and technical device success also improved with Resilia.

“Based on this result, innovation with the balloon-expandable transcatheter valve might close the gap [in] hemodynamic outcomes with the self-expandable valve in small aortic annuli,” said Hioki.

Earlier at the meeting, researchers presented data showing that the Resilia valve, which includes a taller external skirt to limit PVL and a calcium-blocking technology to reduce the risk of structural valve deterioration, had better 1-year clinical outcomes compared with the older-generation Sapien valves.