The addition of an annular sealing skirt, among other design changes in the Acurate neo2 transcatheter aortic valve implantation (TAVI) system (Boston Scientific), has contributed to an improvement in rates of paravalvular leak (PVL) compared to a previous generation of the device, findings from a postmarket clinical follow-up study presented at PCR London Valves (27–29 November, London, UK) suggest.
This was among the talking points raised by Won-Keun Kim (Kerckhoff Heart Center, Bad Nauheim, Germany) in his presentation of the 30-day results from the Acurate neo2 postmarket study, during a late-breaking trial session at the PCR London Valves meeting. Findings of the postmarket study were also published in EuroIntervention.
The Acurate neo2 Aortic Valve System received CE mark and was released to the European market in 2020. The device builds upon the earlier-generation Acurate neo platform, CE marked in 2014, and features annular sealing technology designed to conform to irregular, calcified anatomies and further minimise PVL.
“The Achilles’ heel has been a relatively high rate of PVL, around 10% in the SCOPE I and II studies,” said Kim of the earlier-generation device, in his PCR London Valves presentation. Data presented at EuroPCR 2021 (18–20 May, virtual) from the Early neo2 and ITAL-neo registries had demonstrated positive procedural performance, including low rates of PVL and permanent pacemaker implementation (PPI). Kim explained that the purpose of the postmarket study was to generate clinical data in routine practice out to one year.
Investigators enrolled 250 patients with severe aortic stenosis at 18 sites across Europe, assessing a primary safety endpoint of all-cause mortality, which occurred in 0.8% of patients. Of the two patients who died, one was due to bleeding after the procedure and another patient experienced valve embolisation and coronary obstruction due to unsuccessful TAV-in-TAV, Kim detailed.
The data also demonstrated that no patients experienced greater than moderate PVL, 1.9% experienced moderate PVL and 18.9% experienced mild PVL. Other notable findings from the study included a low 6.5% rate of new pacemaker implantation 30 days post-procedure, with no incidence of disabling stroke or acute kidney injury.
The study also assessed a primary imaging endpoint to assess hypoattenuated leaflet thickening (HALT) after the procedure, reporting a HALT rate of 24.5% at 30 days post-procedure.
“There was a good haemodynamic improvement and low gradients at 30 days, very low pacemaker rates at 30 days and we have a greater improvement in PVL than observed with prior generation Acurate neo,” said Kim of the study’s main findings. “Ninety-eight percent of patients had mild or no/trace PVL at 30 days and no patients had more than moderate PVL,” he summarised.
Kim’s presentation prompted discussion among panellists at the PCR London Valves late-breaking trial session to consider the potential impact of the design changes from the earlier iteration Acurate neo platform. “The addition of the skirt has made the valve better, but in practical terms how much better?” asked Antoinette Neylon (Hopital Prive Jacques Cartier, Massy, France), as well as asking Kim if this changes the type of anatomy that the technology could be used in.
Kim responded that he and colleagues have compared the performance of Acurate neo to Acurate neo2 looking at the amount of total calcification that can be mitigated by the skirt. “We have also found that it is not the total amount of calcification but more the distribution,” he commented. “So, eccentric calcification would be more critical to the Acurate, even with the skirt. You would be rather careful with very extreme calcification plus eccentric calcification. If it is just concentric and symmetric calcification I think you can use the Acurate neo2.”
Asked for his “bottom line” on the study findings, Kim was pushed on whether he believes the results show that Acurate neo2 is non-inferior or similar to other devices in the market. “You cannot say that there is one valve that is the best,” he remarked, adding: ”It is a difficult question and very political. I would say we have to try to get the best for each patient, and there are different valves with different characteristics.”
Commenting on the patients who may benefit most from the Acurate neo2 valve, Kim said: “I would prefer those patients with small anatomies, low to moderate rate of calcification with high risk of conduction disturbances and importance of coronary access.”
In a press release circulated by Boston Scientific following the presentation of the results, Lars Søndergaard, (Rigshospitalet, Copenhagen, Denmark) also highlighted the change in annular sealing technology and its contribution to the lower rate of PVL with the new generation device.
“With this foundational dataset, we now have postmarket surveillance results that validate the use of the current-generation Acurate neo2 valve for the management of patients with severe aortic stenosis,” Søndergaard was quoted as saying. “The data suggest that the annular sealing technology minimises leakage around the valve—providing greater improvement in PVL than observed with the prior-generation Acurate neo valve—all while maintaining single-digit permanent pacemaker rates, which contributes to better long-term patient outcomes.”