Abstract 11788: Dyslipidemia Affects the Lipid Ratio in Culprit Lesions of Negative Remodeling Vessels in Patients with Acute Coronary Syndrome
Introduction: Dyslipidemia is a major risk factor for ischemic heart disease. Positive remodeling occurs more commonly in acute coronary syndrome (ACS) than in stable angina pectoris (SAP). However, the effects of dyslipidemia on vessel remodeling and plaque characteristics are unclear. Recently, coronary plaque characteristics were analyzed using integrated backscatter IVUS (IB-IVUS). We aimed this study at evaluating the effects of dyslipidemia on the plaque characteristics of culprit lesions in ACS and SAP patients.
Methods: We compared the culprit plaque tissue characteristics in ACS and SAP patients who underwent IB-IVUS before percutaneous coronary intervention. The vessel remodeling index (RI) was calculated for each culprit lesion. We defined an RI ≤ 0.95 as negative remodeling (NR group) and RI > 0.95 as intermediate or positive remodeling (PR group). The patients were divided into 4 groups: SAP-PR, SAP-NR, ACS-PR, and ACS-NR. We then evaluated the effect of different levels of low-density lipoprotein cholesterol (LDL-C) on each plaque component, i.e., the calcified component, fibrous component, and lipid pool (LP), on the basis of the IB values.
Results: We analyzed 102 patients (45 ACS and 57 SAP patients). Significant differences were observed between the ACS and SAP patients in their LP percent volume (34.4 ± 9.4% vs. 24.0 ± 7.7%, respectively; p < 0.001), RI values (0.98 ± 0.2 vs. 0.77 ± 0.2, respectively; p < 0.001), and the PR prevalence (44% vs. 12%, respectively; p = 0.01). In the ACS-NR group, a significant linear correlation was observed between the LDL concentration and the LP percent volume (r = 0.628; p = 0.01). No significant correlations were observed between the LDL concentration and any other plaque component in the SAP-PR, SAP-NR, and ACS-PR groups.
Conclusions: The culprit plaques of the ACS patients had a larger LP than those in the SAP patients. We conclude that an increase in the LP causes plaque instability. In patients with ACS, the LDL concentration might affect the lipid ratio in the culprit lesions of NR plaques more directly than it would in the culprit lesions of PR plaques because of the smaller plaque volume in NR.
- © 2011 by American Heart Association, Inc.