Two-year findings of a post-hoc study from the GALILEO trial, investigating the clinical outcomes after successful transcatheter aortic valve implantation with a balloon-expandable or a self-expanding valve, suggest that there are comparable outcomes between the two devices.
This was among the conclusions presented by Taishi Okuno (University Hospital of Bern, Bern, Switzerland) during a late-breaking presentation at PCR London Valves (21–23 November, London, UK and virtual).
After recent updates in both European and North American guidelines, TAVI has become a first-line treatment option for elderly symptomatic patients with severe aortic valve stenosis irrespective of surgical risk, Okuno noted in his presentation.
To optimise a TAVI procedure there are multiple device options, he added with different technologies in bioprosthesis designs and also different deployment systems.
“As there are no definitive data to prioritise one device over another, device selection between balloon-expandable and self-expanding transcatheter heart valves is usually based on individual patient anatomy and local operator or heart team experience, focusing primarily on the successful implantation of the device,” Okuno said, adding that it remains unclear whether there are differences in mid- to long-term clinical outcomes between the devices once successfully implanted with intended valve performance.
Okuno and colleagues compared two-year clinical outcomes after successful implantation of the CoreValve or Evolut (Medtronic) self-expanding valves and Sapien 3 and Sapien XT (Edwards Lifesciences) balloon-expandable valves, in the context of the GALILEO trial.
GALILEO was a randomised, open-label, event-driven trial comparing low dose rivaroxaban-based versus antiplatelet-based antithrombotic therapies in patients without an established indication for oral anticoagulation after successful TAVI.
Successful TAVI was defined as placement of a single transcatheter heart valve into the proper anatomical location achieving the intended valve performance without peri-procedural complications. The primary endpoint of the trial was major adverse cardiac and cerebrovascular events (MACCE), a composite of all-cause death or thromboembolic events including: stroke, myocardial infarction (MI), symptomatic valve thrombosis, systemic embolism, deep-vein thrombosis or pulmonary embolism, Okuno detailed.
Among 1,644 patients recruited in 136 centres across 16 countries between December 2015 and May 2018, 499 received a self-expanding valve and 757 patients a balloon-expandable valve. Patients treated with the self-expanding valve were less likely to be male, had higher surgical risk score and a lower haemoglobin level, and were more likely to have a permanent pacemaker at baseline as compared to those with a balloon-expandable valve, Okuno explained.
Most patients in both arms were treated with newer-generation devices, he said, adding that mean valve size was larger, and the portion of valve-in-valve procedures for degenerated prostheses was higher for the self-expanding TAVI procedure than the balloon-expandable procedure.
“After the procedure, the self-expanding valve was associated with a larger effective orifice area, and a lower mean aortic valve gradient, but had a higher rate of paravalvular regurgitation as compared to a balloon-expandable valve,” he said.
Detailing the results, Okuno explained that there were no significant differences in the primary endpoint of MACCE, and also its components including all-cause death and stroke, while there was also no significant difference in the occurrence of major or life-threatening bleeding between the two groups at two years.
Patients with a higher risk profile at baseline were more likely to have been selected for a self-expanding than a balloon-expandable transcatheter heart valve, he said, adding that after successful TAVI, a self-expanding transcatheter heart valve was associated with more favourable forward-flow haemodynamics but inferior outcomes in terms of paravalvular regurgitation compared with a balloon-expandable transcatheter heart valve.
Mortality, thromboembolic and bleeding outcomes did not differ significantly up to two years between the valves after successful implantation, he added.
Okuno noted that there were limitations of the study, including that it was a post-hoc analysis based on a clinical trial in which the selection of valve type was made by a treating heart team at each participating centre in a non-randomised fashion. Thus, the findings may be confounded by unmeasured variables and need to be interpreted with caution, he said.
In conclusion, Okuno said that the two-year follow-up data from the GALILEO trial indicate that successful TAVI, either with newer generation self-expanding or balloon-expandable valves according to physician discretion results in comparable clinical outcomes.
“The findings support current real-world practice where the TAVI devices are chosen based on individual patient anatomy to achieve the primary goal of successful implantation with optimal device and procedural outcome,” he said.
