Tissue characterization identifies subjects with high risk of cardiovascular diseases.

Objective: This study was conducted to examine whether tissue characterization of the carotid artery wall by determining integrated backscatter (IBS) can identify subjects with a recent history of acute coronary syndrome (ACS) or atherothrombotic infarction (ATI).
Research Design and Methods: The maximum thickness (Max-IMT) and IBS value (corrected-IBS) of the carotid artery intima-media complex were measured ultrasonographically for 132 type 2 diabetic subjects (62.9+/-8.5 (+/-S.D.) years old, 87 men and 45 women) with or without cardiovascular diseases.
Results: The diabetic patients with recent ACS or ATI had a significantly lower corrected-IBS and higher Max-IMT than those with Max-IMT > or = 1.1mm but without cardiovascular diseases. The product of Max-IMT and corrected-IBS (IMT-IBS product) of the patients with recent ACS was significantly lower than that of the patients with chronic stable angina. The multiple logistic model showed that only the IMT-IBS product was associated with a recent history of ACS (odds ratio 0.94, P<0.05) and ATI (odds ratio 0.90, P<0.005).
Conclusions: Diabetic patients who had a recent history of ACS or ATI showed a lower IBS value and higher IMT for their carotid artery. Both the size and tissue characteristics of the carotid plaque may identify subjects with a high risk of cardiovascular disease.