The present study was conducted to evaluate the validity and reproducibility of noninvasive brachial-ankle pulse wave velocity (baPWV) measurements and to examine the alteration of baPWV in patients with coronary artery disease (CAD). Simultaneous recordings of baPWV by a simple, noninvasive method and aortic pulse wave velosity (PWV) using a catheter tip with pressure manometer were performed in 41 patients with CAD, vasospastic angina, or cardiomyopathy. In 32 subjects (15 controls and 17 patients with CAD), baPWV was recorded independently by two observers in a random manner. In 55 subjects (14 controls and 41 patients with CAD), baPWV was recorded twice by a single observer on different days. baPWV were compared among 172 patients with CAD (aged 62 +/- 8 years); 655 age-matched patients without CAD but with hypertension, diabetes mellitus, or dyslipidemia; and 595 age-matched healthy subjects without these risk factors. baPWV correlated well with aortic PWV (r=0.87, p<0.01). Pearson's correlation coefficients of interobserver and intraobserver reproducibility were r=0.98 and r=0.87, respectively. The corresponding coefficients of variation were 8.4% and 10.0%. baPWV were significantly higher in CAD patients than in non-CAD patients with risk factors, for both genders (p<0.01). In addition, baPWV were higher in non-CAD patients with risk factors than in healthy subjects without risk factors. Thus, the validity and reproducibility of baPWV measurements are considerably high, and this method seems to be an acceptable marker reflecting vascular damages. baPWV measured by this simple, noninvasive method is suitable for screening vascular damages in a large population.