Evaluation of Regional Aortic Distensibility Using Color Kinesis

Abstract

Regional aortic stiffness cannot be evaluated by conventional methods. Regional aortic wall velocity during systole in the descending aorta was evaluated by using transesophageal echocardiography with color kinesis. The authors defined regional aortic distensibility (RAD) by considering pulse pressure, with RAD (μm/s/mm Hg) = (regional aortic wall velocity)/(pulse pressure). RAD was evaluated in 38 patients who had coronary artery disease (CAD) and 10 who did not. RAD decreased depending on aging (partial regression coefficient was -5.39 x 10^-1, p < 0.001), and RAD was lower in the CAD group than that in the no-CAD group (p < 0.05). In the CAD group, 19 patients had a single fixed plaque (4 calcified and 15 noncalcified plaques). RAD in the calcified plaque was lower than that in the noncalcified plaque (p<0.01), and RAD was lower in the noncalcified plaque than that in the no-plaque region (p < 0.05). In noncalcified plaques, the relation between RAD and maximum intimal thickness had a signifi cant correlation, r = 0.7, p<0.001. The residual of RAD from the regression line was signifi cantly larger in the calcified plaque than that in the noncalcified plaque (p< 0.001). In conclu sion, RAD can express increasing regional aortic wall stiffness brought about by arteriosclerosis quantitatively. Color kinesis provides information on characteristic difference between calcified and noncalcified plaque.