Ankle-brachial index and its link to automated carotid ultrasound measurement of intima-media thickness variability in 500 Japanese coronary artery disease patients

The purpose of this study was to evaluate whether the carotid intima-media thickness (cIMT) and intima-media thickness variability (IMTV) along the artery are correlated to the ankle-brachial index (ABI) in Japanese coronary artery disease patients. Five hundred consecutive patients (312 males; median age 69 ± 11 years) who underwent carotid ultrasonography and first coronary angiography were prospectively analyzed. By using automated software (AtheroEdge™, AtheroPoint, Roseville, CA, USA), we obtained the cIMT and IMTV. Pearson correlation analysis was performed to calculate the association between ABI, automatically measured cIMT, automatically measured IMTV, and the SYNTAX score. The mean cIMT was 0.881 ± 0.334 mm and the mean IMTV was 0.141 ± 0.112. IMTV was negatively and significantly correlated to ABI (ρ = -0.147; p = 0.001), whereas cIMT was not (ρ = -0.075; p = 0.097). IMTV and cIMT had the same significant correlation with the SYNTAX score. When we considered patients with a higher risk factor (ABI ≤ 0.9), we found higher values of IMTV and the SYNTAX score, but not higher values of cIMT. Logistic regression analysis showed that IMTV was independently associated with the complexity of the coronary artery disease (as assessed by the SYNTAX score). In conclusion, we show that IMTV automatically measured using AtheroEdge™ was correlated with ABI, whereas cIMT was not. IMTV could be integrated with cIMT measurement to improve the assessment of cardiovascular disease.