Aims: Transoesophageal echocardiography (TEE) is considered the gold standard method for annulus measurement in transcatheter aortic valve implantation (TAVI). However, computed tomography (CT) has potential advantages compared to TEE. We sought to assess the impact of CT-guided valve sizing on post-procedural aortic regurgitation (AR).
Methods and results: We compared procedural characteristics and clinical outcomes in patients undergoing either TEE-guided or CT-guided TAVI. Among 350 consecutive TAVI recipients, the mean age was 83.2 ± 6.4 years and the logistic EuroSCORE was 22.4 ± 11.2%. The mean Diam-TEE was similar in both groups (22.3 ± 1.9 mm vs. .0 ± 1.8 mm, p=0.092). The mean annulus diameter by CT (mDiam-CT) was larger than mean Diam-TEE (23.6 ± 2.0 mm vs. 22.3 ± 1.9 mm, p<0.001), and resulted in larger valve implant sizes compared to the TEE-guided group (25.8 ± 2.1 mm vs. 25.0 ± 1.9 mm, p<0.001). The incidence of post-procedural AR ≥ grade 2 was significantly reduced in the CT-guided group (15.4% vs. 24.0%, p=0.044), with a similar risk of annulus rupture (0.6% vs. 1.7%, p=0.31). The only predictor of post-procedural AR ≥ 2 was the "valve/mDiam-CT ratio" (HR 0.36 by increase of 0.1, 95% CI: 0.17-0.77, p=0.008) by multivariate analysis.
Conclusion: CT-guided valve sizing in TAVI significantly reduces the incidence of post-procedural AR compared to TEE sizing. This strategy may have the potential to improve clinical outcomes.