Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) with a self-expanding Evolut valve was associated with better hemodynamics on echocardiography than a balloon-expandable Sapien valve in patients with small failed surgical valves in the LYDEN trial.
Intraprocedural invasive valve hemodynamics and 30-day clinical outcomes were not significantly different in the study — the first randomized comparison of the two valve types for ViV.
Observational studies suggest a potential hemodynamic advantage of self-expanding supra-annular valves in ViV, particularly in small surgical valves. The retrospective comparative data, however, had significant heterogeneity of surgical valve types and mechanism of bioprosthesis dysfunction, which may have led to a significant bias when comparing valve performance, suggested lead author Josep Rodés-Cabau, MD, PhD, Quebec Heart and Lung Institute, Laval University, Quebec City, Canada.
To prospectively study the matter, the LYDEN trial randomized 102 patients with a small (≤23 mm) failed surgical valve to receive either a 20 mm or 23 mm Sapien 3/Ultra valve (Edwards Lifesciences) or a 23 mm or 26 mm CoreValve Evolut R/Pro/Pro+ valve (Medtronic). Their mean age was 80 years and median Society of Thoracic Surgeons score was 5%.
The primary endpoint was maximal and mean residual gradients, severe prosthesis/patient mismatch (PPM), or moderate to severe aortic regurgitation assessed by Doppler-echocardiography at 30 days.
The valve was successfully implanted in all 98 patients who underwent the ViV TAVR procedure. Balloon pre- and postdilation was similar between groups, whereas surgical ring fracture was higher with the Sapien balloon-expandable valve (BEV) than the Evolut self-expanding valve (SEV) (35% vs 13%).
Periprocedural complications and 30-day adverse events were “extremely low” irrespective of valve type, Rodés-Cabau said during a hotline presentation at EuroPCR 2022, which coincided with publication of the study in the Journal of the American College of Cardiology.
One procedural complication, a coronary obstruction, occurred in the BEV group, but it resolved with percutaneous coronary intervention. At 30 days, there were no deaths, strokes, or permanent pacemakers, but there was one myocardial infarction in the SEV group and one major vascular complication and one major bleed in the BEV group.
The BEV group had higher mean (23 vs 15 mm Hg; P < .001) and maximal (40 vs 23 mm Hg; P < .001) transvalvular gradients, which translated into a higher rate of BEV patients with a mean residual gradient greater than 20 mm Hg (62% vs 21%; P = .001).
There was a tendency toward a higher rate of severe prosthesis/patient mismatch in the BEV group when classified using the VARC-2 definition (64% vs 44%; P = .07) and the VARC-3 definition, which includes body mass index (39% vs 20%; P = .053).
There were no cases of moderate or severe aortic regurgitation.
Invasive hemodynamic measurements obtained in 55 patients during TAVR were lower than echocardiographic measurements a median of 1-day after the procedure (mean gradients, 14 vs 19 mm Hg; P < .001), but were not significantly different between the BEV (15 vs 23 mm Hg) and SEV (12 vs 15 mm Hg) groups (P = .07).
The difference between the echocardiographic and invasive gradients is likely explained by the pressure recovery phenomenon, Rodés-Cabau said.
“The primary endpoint showed that the Evolut valve system was associated with improved valve hemodynamics compared to the SAPIEN valve as evaluated by Doppler echocardiography,” he said.
The study was limited, he added, by the relatively small sample size and the fact that invasive hemodynamic measurements were taken in only about half the cohort. In addition, surgical ring fracture was left to the discretion of the heart team, which could bias the final results, and the follow-up was limited.
Discussant Azeem Latib, MD, Montefiore Health System, Bronx, New York, congratulated the investigators on “a difficult study to do and, to me, probably one of the most important studies being presented at PCR.”
Commenting further, Latib said that “because we’re dealing with small anatomies, there are many people that would argue that gradients are not the best way to evaluate it, especially as spatial small anatomies will have small aortas and there’ll be more pressure recovery. So, are you looking at DVIs [Doppler velocity indexes] as well as another variable?”
Rodés-Cabau said they will be evaluated in future substudies. “Because you are absolutely right, sometimes the gradient can really be misleading in some of these patients because of the pressure recovery phenomenon.”
Discussant Ganesh Manoharan, MD, Royal Victoria Hospital, Belfast, Northern Ireland, United Kingdom, asked whether the investigators looked at clinical symptoms “because in some of these patients with small valves, even if you drop the gradient by 20 mm Hg, the symptoms immediately disappear.”
Rodés-Cabau said they didn’t during 30-day follow-up but, per protocol, the patients will be followed and further studies will look at symptom improvement.
“I agree with you, and this is why I think it makes sense to do more studies in this field because there is sometimes a mismatch in terms of the clinical outcomes that are usually quite good, despite sometimes relatively high gradients, and I think we need to better understand this,” he said.
The panel also wrestled the high rates of severe PPM in both groups and whether patients with failed small surgical valves should be treated with repeat surgical aortic valve replacement (SAVR) or TAVR.
“The disappointing point of the LYDEN trial is that there is a high number of patients who suffer from severe PPM after TAVI in SAVR,” session comoderator Olaf Wendler, MD, PhD, chair of the Heart, Vascular and Thoracic Institute, Cleveland Clinic London, told theheart.org | Medscape Cardiology.
The reason is that many patients already have small surgical prostheses to start with and, thus, there isn’t sufficient space to take the additional transcatheter valve, he said. As a result, patient symptoms are not relieved and prognosis is poor.
“Therefore, the automatism should not be to treat all failing bioprostheses with TAVI, but that heart teams around the world need to identify patients who are at risk of PPM before they perform TAVI in failing surgical valves,” Wendler said.
“If patients are at risk for PPM and if they are surgical candidates otherwise, they should more liberally be offered repeat SAVR,” he said.
Rodés-Cabau reports grants/research support from Abbott, Boston Scientific, Edwards Lifesciences, and Medtronic; and honoraria or consultation fees from Edwards, Medtronic, and V-Wave. Manoharan reports consultation fee/honoraria/speaker’s bureau participation for Medtronic and Abbott Vascular. Wendler reports grants and contracts with Edwards; honoraria/speakers bureau participation from Edwards, Medtronic, Neovasc; and support for attending meetings from Edwards, Abbott, and Neovasc.
Congress of the European Association of Percutaneous Coronary Interventions (EuroPCR) 2022. Presented May 18, 2022.
J Am Coll Cardiol. Published online May 18, 2022. Abstract