OBJECTIVETo evaluate the components and characteristics of coronary atherosclerotic plaques in type 2 diabetic patients using virtual histology intravascular ultrasound (VH-IVUS).

METHODSIn vivo atherosclerotic plaques (over 50% angiographic diameter stenosis) of the three main coronary arteries were analyzed by gray-scaled IVUS with planar and volumetric VH-IVUS in consecutive patients examined between September 2008 and March 2009. Patients were divided into two groups: diabetic mellitus (DM) group with 22 patients (39 lesions) and non-DM group with 46 patients (69 lesions).

RESULTSAt the minimal lumen area (MLA) site, the percentage of NC (necrotic core) area (19.4% +/- 1.2% vs. 15.1% +/- 1.1%, P = 0.015) and dense calcium (DC) area (15.2% +/- 1.6% vs. 10.7% +/- 1.1%, P = 0.016) were significantly larger while fibrotic tissue (FT) area (56.7% +/- 2.3% vs. 64.8% +/- 1.8%, P = 0.007) was smaller in DM group than in non-DM group. Likewise, volumetric VH-IVUS analysis showed that the percentage of NC volume (21.3% +/- 1.3% vs. 16.5% +/- 1.1%, P = 0.008) and DC volume (16.6% +/- 1.4% vs. 11.3% +/- 1.1%, P = 0.003) were significantly larger while FT volume (55.1% +/- 2.1% vs. 63.9% +/- 1.8%, P = 0.003) was significantly smaller in DM group than in non-DM group. Moreover, significantly higher incidence of VH-TCFA (thin-cap fibro atheromas) was evidenced in the DM group than in the non-DM group (69.2% vs. 42.0%, P = 0.009). However, the remodeling index and the positive remodeling frequency were similar between the 2 groups.

CONCLUSIONIncidence of necrotic core, dense calcium plaque and vulnerable plaques in stenotic lesions was higher in DM patients than in non-DM patients.