Visualization of coronary plaque in arterial remodeling using a new 40-MHz intravascular ultrasound imaging system.

OBJECTIVES: The aim of this study was to characterize coronary plaque in target lesions with vessel remodeling using iMap-intravascular ultrasound (IVUS).
BACKGROUND: The relationship between the plaque component and vessel remodeling remains to be elucidated. iMAP-IVUS is an imaging system that can be used to assess the plaque composition by radiofrequency signals from 40 MHz IVUS.
METHODS: IVUS examinations were performed for the de novo target vessels of 146 stable angina pectoris patients (174 vessels). The patients were divided into two groups: including a nonpositive remodeling group (non-PR, remodeling index ≤ 1.0, 125 vessels) and a positive remodeling group (PR, remodeling index > 1.0, 49 vessels).
RESULTS: The percent plaque burden in the PR group were lager than those in the non-PR group (79.05% vs. 74.36%, P < 0.01). Attenuation plaques were more frequently observed in PR group (40.8% vs. 12.1%, P < 0.0001). The percentages of lipidic and necrotic relative areas at the minimum lumen sites were greater in the PR group than in the non-PR group (7.22% vs. 6.03%, P <0.05 and 22.08% vs. 14.71%, P < 0.001, respectively), and the percentage of the fibrotic area was smaller (54.82% vs. 61.42%, P < 0.05). In addition, a positive linear correlation was observed between the remodeling index and either the lipidic or necrotic area (r = 0.37, P <0.0001 and r = 0.35, P < 0.0001, respectively).
CONCLUSIONS: The coronary plaque characteristics in PR patients showed increased lipidic and necrotic areas and the degree of coronary remodeling correlated with the lipidic and necrotic plaque area. © 2012 Wiley Periodicals, Inc.