Worryingly, mismatch at 1 year also predicted death from all causes at 3 years, prompting calls for RCTs in this setting.
BOSTON, MA—Compared to balloon-expandable bioprosthetic aortic valves, self-expanding devices show superior hemodynamic performance at 1 year in patients with small annuli undergoing TAVI, according to new registry data. Additionally, use of a balloon expandable valve was associated with moderate or severe patient-prosthesis mismatch (PPM) at 1 year, which was also an independent predictor of all-cause mortality at 3 years.
Observational results should be interpreted with caution, said Walid Ben-Ali, MD, PhD (Montreal Heart Institute, Canada), who presented the data today at TCT 2022, but “basically when you have severe PPM at 1 year, you have a double relative risk of all-cause mortality at 3 years.
The results are not yet sufficient to suggest that all patients with small annuli should be treated with self-expanding valves, several experts said.
“I think it’s very difficult when you have these propensity analyzes to make definitive decisions based on that,” said Alexandra Lansky, MD (Yale University School of Medicine, New Haven, CT), during a discussion in the last clinical trial session. “It’s important. I think it needs to be validated. You need long-term follow-up. You need matched populations and so on. So I think validating that in a prospective trial is important.
Similarly, Susheel Kodali, MD (NewYork-Presbyterian/Columbia University Irving Medical Center, NY), warned the public that it is easy to be seduced by large sets of observational data and the signals they can suggest, “especially when you’re dealing with devices that are so different. He pointed out that valve types are chosen for a variety of reasons, including life management, the need for a pacemaker, and access coronary.
“We all agree that we want the most valve area, and we struggle to gauge that, what valve area really is, and we make decisions based on a lot of factors,” Kodali continued. “It’s really enticing, but we have to wait for the data to answer the question that’s been asked: will it impact . . . device choice?”
Panelists agreed that the current CLEVER essay will hopefully yield more definitive answers in this space.
For the study, Ben-Ali and colleagues included data on 1,195 patients from the FRANCE-TAVI registry with small aortic annuli, defined as diameter ≤ 23 mm or indexed diameter ≤ 12 mm/meter2 measured on CT – who underwent TAVI with either a self-expanding supra-annular valve (Sapien 3; Edwards Lifesciences) or a balloon-expandable device (Evolut R/Pro; Medtronic).
The researchers conducted propensity matching using two methods. The first (n=928) used 10 anatomical and clinical variables to create a propensity score and patients were matched 1:3 on whether they were treated with a self-expanding or balloon-expanding device. The second (n = 1195) used the propensity score to generate an inverse probability treatment weight (IPTW) as a sensitivity analysis.
After matching, the two cohorts were comparable in terms of demographic data and baseline echocardiographic and computed tomography data as well as procedural and post-procedural outcomes. However, hemodynamic performance was significantly better with self-expanding supra-annular valves compared to balloon-expandable devices in terms of lower mean gradient and larger index effective orifice area at discharge, 30 days and 1 year (P
Rates of moderate or severe PPM at 1 year were significantly higher in the balloon-expandable valve groups than in the self-expanding valve groups before and after pairing (P
“Patients treated with expandable balloon valves have a three-fold relative risk of developing moderate to severe PPM at 1 year,” Ben-Ali said.
Additionally, severe PPM at 1 year (HR 2.01; 95% CI 1.02-3.95), index hospitalization duration (HR 1.05 per 1 day increment; 95% CI 1 .01-1.09), major bleeding (HR 2.86; 95% CI 1.07-7.66) and atrial fibrillation (HR 3.46; 95% CI 2.08-5.74) were all found to be independent predictors of 3-year mortality in the first matching strategy. Using the IPTW strategy, valve type (HR 1.93; 95% CI 1.2-3.11) and annulus size (HR 1.23 per 1 mm decrease; 95% CI 1.06-1.41) were also predictors of 3-year all-cause mortality.
“Power of the big ledgers”
During the discussion, Bernard Prendergast, MD (St Thomas’ Hospital, London, England), stated that the assessment of PPM is well known to be complicated “and making these measurements in the context of a registry national without a central laboratory is a very difficult call. That said, he continued, I think that this study and [the TEER SHOCK registry presented in the same session] showed the power of ledgers to produce data that guides the field. And although the patient-prosthesis mismatch is not so important in very old patients, many of whom are in this registry, we know from surgical data that PPM is important in younger patients.
Prendergast added, “These data are a call to our industry colleagues and engineers designing new valves to think about the needs of patients with small annuli as we transition to the fourth and fifth generations of TAVR devices.”
This data is a call to our industry colleagues and engineers designing new valves to think about the needs of patients with small rings as we transition to the fourth and fifth generations of TAVR devices. Bernard Prendergast
At a press conference, Michael Young, MD (Dartmouth-Hitchcock Medical Center, Lebanon, NH), said he was “cautiously reassured about the results of this, because in our practice, I think we’re thinking about it. very carefully. He added that some of the surgeons at his institutions are “aggressive about doing root enlargements in hopes that these little rings will get a bigger surgical prosthetic valve.”
In his practice, Young added, “we’ve moved toward a supra-annular design” for patients with small annuli. Many end up with a “17-20 mm Hg gradient when they start with a 40 mm Hg gradient. They feel better, they generally feel good, but you just don’t know, number one, durability and then , number two, what their clinical outcomes will be.
Another issue that comes into play when choosing a bioprosthesis involves lifetime patient management, Young said. “It actually entered into the discourse in terms of choosing SAVR vs TAVR at this point. Usually when the ring is small we also look at the sinuses and sometimes the sinuses can be very small. So you worry about sinus sequestration and locking the patient in, so to speak, in the next 5-10 years, who knows what their coronary options will be.
Also at the press conference, Robert Cubeddu, MD (NCH Heart Institute, Naples, FL), said that while the data supports “what we already know and believe, we need to remember that it’s about a retrospective view with an unreferred core. lab definitions of PPM and so on, which are incredibly important.
Waiting for SMART results
The data puts additional pressure on the SMART trial data, David J. Cohen, MD (St. Francis Hospital, Roslyn, NY), said during the TCT session. “And not 1-year results, which will be presented first from this trial, but 5-year results that will give us an idea of whether it really makes a difference for patients, especially patients who are not in the group of extremely old people who can expect to live 5 to 10 years,” he said. “We desperately need that to really know what’s best for this difficult group, because the PPM rates here are not trivial.”
Agreeing, panelist Anita Asgar, MD (Montreal Heart Institute, Canada), said all of this data will become increasingly important as TAVI moves to lower-risk patients. “Hemodynamics that we may not have ignored, but maybe it wasn’t as much of an issue in older people,” she said. “And now, with younger patients, we have to take all of those things into consideration.”
What will also be important is “understanding how these hemodynamics vary under exercise and stress,” she added.
Session co-moderator Jane Leopold, MD (Brigham and Women’s Hospital, Boston, MA) reiterated this point, saying, “The hemodynamics of exercise [are] extremely important, because hemodynamics at rest simply does not predict what the patient is doing when they get up and leave the hospital.