OBJECTIVEDuring progression of atherosclerosis, the vessel may develop either positive or negative remodeling. The pathophysiology of vascular remodeling is not fully understood. This study investigated the relationship between plaque characteristics and arterial remodeling using intravascular ultrasound imaging (IVUS).

METHODSA total of 77 patients (male 53, mean age 58 +/- 10 years) who underwent IVUS imaging (ClearView or Galaxy2, Boston Scientific, USA) of culprit vessel were enrolled in this study. Among the 77 patients, 31 presented with stable angina pectoris and 46 presented with acute coronary syndrome. Qualitative assessment of the lesion and quantitative measurement were performed in both stenotic and reference segments. The lesions were classified into soft plaque and hard plaque (including fibrous plaque, calcified plaque and mixed plaque) according to different ultrasound patterns of tissue reflection. The remodeling index (RI) was defined as the ratio of vessel cross sectional area (EEMcsa) of lesion segment to the mean reference EEMcsa. Positive remodeling was defined as RI > 1.0 and negative remodeling as RI < 1.0.

RESULTSOf 77 lesions, 45 (58%) had undergone positive remodeling, and 32 (42%) had negative remodeling. In comparison to the patients with negative remodeling, patients with positive remodeling presented with more acute coronary syndrome (74% vs. 43%, P = 0.006). Both the plaque area and the vessel area were significantly larger in the lesion with positive remodeling than in lesion with negative remodeling. The lesions with positive remodeling were predominantly soft (71% vs. 34%, P = 0.001) and had less calcification [21% vs. 54%, P = 0.003 and (18 +/- 37) degrees vs. (40 +/- 50) degrees, P = 0.027] compared with lesions with negative remodeling. The difference of clinical presentation and plaque characteristics between the patients with different patterns of remodeling is still significant with binary logistic analysis.

CONCLUSIONSCoronary arterial remodeling pattern is related to the clinical manifestation and the composition of plaque. Lesions presented with positive remodeling have a higher prevalence of soft plaque and less calcification.