Non-Contrast Three-Dimensional Magnetic Resonance Imaging for Pre-Procedural Assessment of Aortic Annulus Dimensions in Patients Undergoing Transcatheter Aortic Valve Implantation

ABSTRACTBackground: We sought to appraise the accuracy of non-contrast three-dimensional (3D) magnetic resonance imaging (MRI) in comparison with computed tomography (CT).Methods: This is a single-center prospective study enrolling 48 consecutive patients with severe aortic stenosis screened for transcatheter aortic valve implantation (TAVI), who underwent non-contrast 3D MRI and standard cardiac CT for pre-TAVI aortic annulus assessment. Systolic MRI dimensions were modelled, by adding a corrective factor (+7.5% of the area). Tests of correlation and agreement were performed.Results: The mean subjective MRI image quality was 3.2±0.8. According to CT, 20 patients (43.5%) had severe or massive annular calcifications. Bland–Altman plots and Passing and Bablock regression analysis showed no relevant differences of cross-sectional area measurements for corrected systolic MRI vs. systolic CT measurements (mean bias 0.09 cm2; 95% limits of agreement: -0.48 to 0.67). Higher bias was seen in patients with severe ...