Impact of carotid artery ultrasound and ankle-brachial index on prediction of severity of SYNTAX score.

BACKGROUND Numerous reports have shown that both carotid artery ultrasound (carotid US) findings and ankle-brachial index (ABI) are associated with the prevalence of coronary artery disease. The relationship between carotid US findings and ABI and the complexity of coronary artery disease (as measured by SYNTAX [SX] score), was evaluated. METHODS AND RESULTS The subjects included 496 consecutive patients who underwent carotid US, ABI analysis and initial coronary angiography. The mean common carotid artery intima-media thickness (mean IMT) was evaluated on carotid US. Patients with mean IMT ≥ 0.9 mm had significantly higher SX scores than patients without thickening (mean IMT <0.9 mm; P<0.0001). Similarly, patients with low ABI (<0.9) had significantly higher SX scores than patients with ABI ≥ 0.9 (P<0.0001). When the patients were divided into 4 groups on the basis of mean IMT and ABI (group A, mean IMT <0.9 mm, ABI ≥ 0.9; group B, mean IMT <0.9 mm, low ABI; group C, mean IMT ≥ 0.9 mm, ABI ≥ 0.9; group D, mean IMT ≥ 0.9 mm, low ABI), the SX scores were significantly different. Among the patients in group D, 75% had coronary artery disease. CONCLUSIONS Carotid US and ABI are associated with SX score. The combination of carotid US and ABI provides useful information for predicting the complexity and presence of coronary artery disease.