Aortic annulus measurement with computed tomography angiography reduces aortic regurgitation after transfemoral aortic valve replacement compared to 3-D echocardiography: a single-centre experience.

BACKGROUND: Accurate assessment of the aortic annulus is crucial for successful transcatheter aortic valve replacement (TAVR), in particular to prevent paravalvular regurgitation (PVR). We compared aortic annular sizing using multidetector computed tomography (MDCT) and three-dimensional transoesophageal echocardiography (3-D TEE) to determine the predictive value of MDCT. METHODS AND
RESULTS: All patients admitted for transfemoral TAVR [n = 227; 48.9% balloon expandable (Edwards Sapien 3); 51.1% self-expandable (Core Valve, Evolut R)] at our institution from January 2015 until December 2016 were analysed retrospectively. Aortic annular parameters were obtained either by MDCT or 3-D TEE. Additionally, we included a cohort of patients (n = 27) assessed by both MDCT and 3D TEE between October 2017 and April 2018 to enable intra-individual comparison of the two methods. Indications for TAVR were severe degenerative aortic stenosis (AS; 94.7%) or re-stenosis after surgical AVR (5.3%). 74.4% were classified as high-gradient AS. The mean age was 80 (37-94) years and 75.8% presented with NYHA III/IV. STS risk of mortality was intermediate (3.5 ± 2.3). MDCT and 3-D TEE were performed in 116 and 111 patients for aortic annulus sizing, respectively. Significantly larger implants were chosen in the CT group irrespective of prosthesis type or post-dilatation. Follow-up (median at 79 days) revealed significantly less PVR in the MDCT compared to 3-D TEE group (absence of PVR in 59.3% and 40.7%, p = 0.016), without differences in mortality. Patients without PVR or mild PVR had a better clinical performance according to NYHA class (p = 0.016).
CONCLUSION: MDCT is superior to 3-D TEE in terms of sizing accuracy and clinical outcomes. Reduction of PVR after TAVR with MDCT is likely due to valve annulus undersizing by TEE.