A New Method for Aortic Valve Planimetry with High-Resolution 3-Dimensional MRI and Its Comparison with Conventional Cine MRI and Echocardiography for Assessing the Severity of Aortic Valvular Stenosis

• Published in: Korean journal of radiology Vol. 22; no. 8; pp. 1266 - 1278
• Main Authors: Kim, Hae Jin, Choe, Yeon Hyeon, Kim, Sung Mok, Kim, Eun Kyung, Lee, Mirae, Park, Sung Ji, Ahn, Joonghyun, Carriere, Keumhee C
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Society of Radiology 01.08.2021; 대한영상의학회
• Subjects: Aged; Aortic Valve - diagnostic imaging; Aortic Valve Stenosis - diagnostic imaging; Cardiovascular Imaging; Constriction, Pathologic; Coronary vessels; Echocardiography; Humans; Magnetic Resonance Imaging; Magnetic Resonance Imaging, Cine; Middle Aged; Reproducibility of Results; Software; Velocity; Work stations; 방사선과학; Aortic stenosis; Cardiac magnetic resonance imaging, Echocardiography; Aortic valve; Planimetry
• ISSN: 1229-6929; 2005-8330; 2005-8330
• DOI: 10.3348/kjr.2020.1218

We aimed to compare the aortic valve area (AVA) calculated using fast high-resolution three-dimensional (3D) magnetic resonance (MR) image acquisition with that of the conventional two-dimensional (2D) cine MR technique. We included 139 consecutive patients (mean age ± standard deviation [SD], 68.5 ± 9.4 years) with aortic valvular stenosis (AS) and 21 asymptomatic controls (52.3 ± 14.2 years). High-resolution T2-prepared 3D steady-state free precession (SSFP) images (2.0 mm slice thickness, 10 contiguous slices) for 3D planimetry (3DP) were acquired with a single breath hold during mid-systole. 2D SSFP cine MR images (6.0 mm slice thickness) for 2D planimetry (2DP) were also obtained at three aortic valve levels. The calculations for the effective AVA based on the MR images were compared with the transthoracic echocardiographic (TTE) measurements using the continuity equation. The mean AVA ± SD derived by 3DP, 2DP, and TTE in the AS group were 0.81 ± 0.26 cm², 0.82 ± 0.34 cm², and 0.80 ± 0.26 cm², respectively ( = 0.366). The intra-observer agreement was higher for 3DP than 2DP in one observer: intraclass correlation coefficient (ICC) of 0.95 (95% confidence interval [CI], 0.94-0.97) and 0.87 (95% CI, 0.82-0.91), respectively, for observer 1 and 0.97 (95% CI, 0.96-0.98) and 0.98 (95% CI, 0.97-0.99), respectively, for observer 2. Inter-observer agreement was similar between 3DP and 2DP, with the ICC of 0.92 (95% CI, 0.89-0.94) and 0.91 (95% CI, 0.88-0.93), respectively. 3DP-derived AVA showed a slightly higher agreement with AVA measured by TTE than the 2DP-derived AVA, with the ICC of 0.87 (95% CI, 0.82-0.91) vs. 0.85 (95% CI, 0.79-0.89). High-resolution 3D MR image acquisition, with single-breath-hold SSFP sequences, gave AVA measurement with low observer variability that correlated highly with those obtained by TTE.