Validation and reproducibility of aortic pulse wave velocity as assessed with velocity‐encoded MRI

Abstract

Purpose To validate magnetic resonance imaging (MRI) assessment of aortic pulse wave velocity (PWV_MRI) with PWV determined from invasive intra‐aortic pressure measurements (PWV_INV) and to test the reproducibility of the measurement by MRI. Materials and Methods PWV_MRI was compared with PWV_INV in 18 nonconsecutive patients scheduled for catheterization for suspected coronary artery disease. Reproducibility of PWV_MRI was tested in 10 healthy volunteers who underwent repeated measurement of PWV_MRI at a single occasion. Velocity‐encoded MRI was performed on all participants to assess PWV_MRI in the total aorta (Ao_total), the proximal aorta (Ao_prox), and the distal aorta (Ao_dist). Results The results are expressed as mean ± SD, Pearson correlation coefficient (PCC), and intraclass correlation (ICC). Good agreement between PWV_MRI and PWV_INV was found for Ao_total (6.5 ± 1.1 m/s vs. 6.1 ± 0.8 m/s; PCC = 0.53), Ao_prox (6.5 ± 1.3 m/s vs. 6.2 ± 1.1 m/s; PCC = 0.69), and for Ao_dist (6.9 ± 1.1 m/s vs. 6.1 ± 1.0 m/s; PCC = 0.71). Reproducibility of PWV_MRI was high for Ao_total (4.3 ± 0.5 m/s vs. 4.6 ± 0.7 m/s; ICC = 0.90, P < 0.01), Ao_prox (4.3 ± 0.9 m/s vs. 4.7 ± 1.0 m/s; ICC = 0.87, P < 0.01), and Ao_dist (4.3 ± 0.6 m/s vs. 4.4 ± 0.8 m/s; ICC = 0.92, P < 0.01). Conclusion MRI assessment of aortic pulse wave velocity shows good agreement with invasive pressure measurements and can be determined with high reproducibility. J. Magn. Reson. Imaging 2009;30:521–526.