Supra-annular self-expanding valves significantly reduced clinical valve thrombosis by 81% (RR 0.19) compared to intra-annular balloon-expandable valves in patients with severe aortic stenosis.
Meta-Analysis (n=1,877)
Randomized
Yes
Does a self-expanding supra-annular valve reduce clinical and sub-clinical valve thrombosis compared to a balloon-expandable intra-annular valve in patients undergoing TAVI?
In patients undergoing TAVI, self-expanding supra-annular valves are associated with a significantly lower risk of clinical and sub-clinical valve thrombosis compared to balloon-expandable intra-annular valves, though this does not translate into differences in stroke, re-intervention, or death.
Effect estimate: RR 0.19 (95% CI 0.04-0.86)
Absolute Event Rate: 0.4% vs 2.1%
p-value: p=0.03
Background: Transcatheter aortic valve implantation (TAVI) is an established treatment for severe aortic stenosis. The two most widely used platforms are either balloon-expandable intra-annular valve (BEV, Edwards) or self-expanding supra-annular valve (SEV) from Medtronic. Comparative data related to clinical and sub-clinical valve thrombosis are limited. The aim of this study-level meta-analysis is to evaluate its incidence and whether this translates into any difference in clinical outcomes. Methods: Electronic databases were searched from inception through to October 2025 to identify randomised clinical trials of patients receiving either platform. Rates of clinical and subclinical valve thrombosis were identified and compared between the two groups. Results: In five randomized controlled trials including 1877 patients, the risk of clinical and sub-clinical valve thrombosis was relatively low in both groups. There was a significant 81% reduction in clinical valve thrombosis in patients undergoing SEV compared to BEV 0.4% vs. 2.1%; rate ratio (RR) 0.19, 95% confidence interval (CI) (0.04 to 0.86), p = 0.03. Similarly, the risk of sub-clinical valve thrombosis was significantly lower in the SEV group 0.6% vs. 3.6%; RR 0.22, 95% CI (0.07 to 0.65), p = 0.006. This difference was not translated into increased risk of stroke, valve re-intervention, or death. Conclusion: Patients undergoing TAVI using SEV compared to BEV have a lower risk of clinical and sub-clinical valve thrombosis in randomized trials, which is largely influenced by small annulus anatomy. Larger studies with longer term follow-up or using a dedicated imaging protocol may provide better insights into the clinical sequelae of this phenomenon.
Ali et al. (Wed,) conducted a meta-analysis in Severe aortic stenosis (n=1,877). Supra-annular self-expanding valve (SEV) vs. Intra-annular balloon-expandable valve (BEV) was evaluated on Clinical valve thrombosis (RR 0.19, 95% CI 0.04-0.86, p=0.03). Supra-annular self-expanding valves significantly reduced clinical valve thrombosis by 81% (RR 0.19) compared to intra-annular balloon-expandable valves in patients with severe aortic stenosis.