METHODS: 60-consecutive patients, who underwent coronary angiography and who's aorto-femoral PWV were obtained with a Judkins catheter, were the subjects of this study. The ASI was obtained for all patients, using CardioVision(R) MS-2000 (IMDP, Las Vegas, NV), with cuff pressure on the brachial artery. The ASI were obtained as follows; 1) at the baseline (ASI-B), 2) after hyperemia induced by compression of the arm with cuff pressure for 5 minutes (ASI-H), 3) after having taken sublingual nitroglycerin (ASI-N).

RESULTS: 34-patients had significant coronary artery disease (CAD) from the coronary angiography findings. All the ASI were positively correlated to the PWV, and were also higher in patients with CAD (ASI-B, 85.9±57.8 vs. 48.2±24.5, p=0.001; ASI-H, 98.1±49.8 vs. 48.1±21.3, p=0.00; ASI-N, 66.7±55.7 vs. 33.2±27.9, p=0.002). The ASI-H was mostly well correlated to the PWV and the severity of CAD (PWV, r=0.49, p=0.00; severity, r=0.52, p=0.00). The ASI was increased after hyperemia in patients with CAD (85.9±57.8 to 98.1±49.8, p=0.01), but was not significantly changed in those without CAD (48.2±24.5 to 48.1±21.3, p=0.68). The ASI-N was decreased in all patients.

CONCLUSIONS: The Arterial Stiffness Index, measured non-invasively by computerized oscillometry, was feasible and useful for detection of atherosclerotic coronary disease. Especially, the difference in the ASI between patients with and without CAD was more apparent after hyperemia. These findings suggest that in addition to stiffening of the arterial wall itself, the impairment of flow mediated vasodilation, due to endothelial dysfunction, further increases the arterial stiffness.