Cardio-ankle vascular index (CAVI) correlates with aortic stiffness in the thoracic aorta using ECG-gated multi-detector row computed tomography.

The cardio-ankle vascular index (CAVI) is an arterial stiffness index based on the stiffness parameter β, which is essentially independent of blood pressure. The objective of this study was to determine whether CAVI correlates with the regional stiffness parameter β and pulse wave velocity (PWV) in the thoracic aorta calculated from ECG-gated multi-detector row computed tomography (MDCT). Forty-nine patients who underwent coronary MDCT for suspicious coronary artery disease were recruited. The largest and smallest vessel luminal cross-sectional areas of the thoracic aorta were measured from MDCT images to calculate PWV and stiffness parameter β of the ascending and descending aorta. CAVI was also measured by VaSera VS-1000. In univariate analysis, CAVI significantly correlated with regional stiffness parameter β and PWV, which was influenced by the inevitable part of the aging process in the ascending (r = 0.485, P < 0.001; r = 0.483, P < 0.001) and descending aortas (r = 0.304, P = 0.034; r = 0.327, P = 0.022), respectively. The regional stiffness parameter β did not correlate with systolic blood pressure (SBP), although the PWV correlated with SBP. In multivariate analysis, CAVI independently correlated with the stiffness parameter β, but not with the PWV. These data suggest that CAVI, which correlated with stiffness parameter β in the thoracic aorta, has a potential role in evaluating integrated arterial stiffness including that of the central aorta.