Comparison of coronary plaque components between non-culprit lesions in patients with acute coronary syndrome without ST segment elevation and target lesions in patients with stable angina: virtual histology – intravascular ultrasound analysis.

 

Norvydas Zapustas1, Ali Aldujeli1, Ramūnas Unikas1

1Hospital of Lithuanian University of Health Sciences Kauno klinikos. Department of interventional Cardiology, Kaunas, Lithuania.

ABSTRACT
Objective:
Patients with acute coronary syndrome (ACS) are thought to have multiple vulnerable coronary plaques components, comparing with stable angina (SAP) patients. We compared relationship between coronary plaque components of non-culprit lesions in patients with acute coronary syndrome without ST segment elevation and target lesions in patients with stable angina: virtual histology – intravascular ultrasound (VH-IVUS) analysis.

Methods: We compared virtual histology – intravascular ultrasound findings between 25 ACS without ST segment elevation non-culprit lesions and 22 stable angina target lesions. Using virtual histology – intravascular ultrasound classified the color-coded tissue into four major components: green (fibro-elastic); light green (fibro-fatty); white (dense calcium) and red (necrotic). Planar VH-IVUS analysis at the minimum luminal site in stable angina pectoris patients’ group and non-culprit lesion at ACS without ST segment elevation and volumetric analysis over a 10-mm-long segment centered at the minimum luminal site was performed.

Results. Patients with ACS without ST elevation the plaque burden was significantly smaller (90,8 ±21 mm3 vs. 102,6 ± 28 mm3, p <0,05) compared with SAP patients’ group. Volumetric analysis showed, non-culprit lesions in acute coronary syndrome without ST segment elevation patients had a greater necrotic core volume (19.1 vs. 12.4, mm3, p<0,05) and dense calcium volume  (15.6 vs. 9.6 mm3, p<0.05) and fibro-fatty volume ( 15.8 vs. 15.5, mm3, p>0,05) compared with target lesions in stable angina patients at the minimum lumen site.

Conclusions: In the present study, the VH-IVUS detected necrotic core was significantly larger in atherosclerotic lesions in patients in acute phase of ACS without ST elevation compared to the stable angina subjects and it could be considered a marker of plaque vulnerability.

Keywords: intravascular ultrasound, coronary plaque, plaque components.