Objective: To investigate (a) the relation between intima-media thickness (IMT) in carotid arteries and the extent of coronary artery disease (CAD); and (b) whether IMT is predictive of coronary atherosclerosis. The coexistence of severe extracranial atherosclerosis in patients with CAD was also analysed.
Methods: Coronary angiography and carotid ultrasound evaluation were performed in 558 consecutive patients (438 men), with a mean (SD) age of 58.8 (9.2) years and suspected CAD. Mean IMT was measured at both carotid arteries and expressed as the mean aggregate value. The relation between IMT and severity of CAD was determined.
Results: A significant correlation between mean IMT and advancing CAD (p < 0.0001) was found. Four independent predictors of CAD were found in the discriminant analysis: age (p = 0.0193), hyperlipidaemia (p < 0.0001), smoking (p = 0.0032), and IMT (p < 0.0001). A significant increase in IMT was observed among patients with one, two, and three vessel CAD. A log normal distribution of IMT values showed that if mean IMT was over 1.15 mm, patients had a 94% probability of having CAD, with sensitivity of 65% and specificity of 80% in the patients with a high risk of CAD. The number of critically stenosed extracranial arteries increased with advancing CAD. None of the patients with normal coronary arteries had severe stenosis of the extracranial arteries. Severe carotid, vertebral, or subclavian stenosis was found in 16.6% of patients with three vessel CAD.
Conclusions: IMT increases with advancing CAD, patients with mean IMT over 1.15 mm have a 94% likelihood of having CAD, and the coexistence of CAD with severe stenosis of aortic arch arteries is relatively high and was found in 16.6% of patients with three vessel CAD.