Aortic knob calcification and coronary artery lesion complexity in non-ST-segment elevation acute coronary syndrome patients

OBJECTIVES
Coronary artery lesion complexity is important for risk stratification of acute coronary syndrome (ACS) patients undergoing cardiac catheterization. SYNTAX score is a pure angiographic measure of anatomic coronary complexity. Chest radiography is a routine examination for evaluating patients with chest pain. There have been no studies to date exploring the relation between aortic knob calcification (AKC) and coronary lesion complexity assessed by SYNTAX score.

STUDY DESIGN
135 consecutive patients with first time diagnosis of non-ST segment elevation ACS were enrolled. SYNTAX score was calculated by dedicated computer software. Aortic calcification was assessed visually.

RESULTS
Patients with AKC had higher SYNTAX score compared to those without AKC (16±6 vs. 11±7, p=0.019). Also, patients with AKC had higher TIMI risk score and were more elderly. Linear regression analysis demonstrated AKC (95% confidence interval [CI] 1.7-6.9, p=0.002), diabetes (95% CI, 1.1-5.7, p=0.005), and smoking (95% CI, 1.2-13.5, p=0.004) as independent determinants of SYNTAX score.

CONCLUSION
Aortic calcification detected on chest X-ray is an independent predictor of complex coronary artery lesions in patients with ACS.