Effect of statin therapy on coronary fibrous-cap thickness in patients with acute coronary syndrome: Assessment by optical coherence tomography study

BackgroundThe thickness of coronary fibrous caps is a major determinant of vulnerable plaques. Several clinical trials have suggested that statin therapy could stabilize vulnerable plaques. Recently, optical coherence tomography (OCT) has been proposed as an effective histology-resolution imaging modality for assessing such micro-structural changes.MethodsForty AMI patients with hyperlipidemia were enrolled and underwent percutaneous coronary intervention (PCI). They were divided into two groups; statin treatment group (n = 23) or control group (n = 17). Serial OCT analyses were performed at baseline and 9-month follow-up for a non-PCI lipid-rich plaque lesion.ResultsThe LDL-cholesterol level in the statin group was significantly lower than that in the control group at follow-up. Although the fibrous-cap thickness was significantly increased in both the statin treatment group (151 ± 110 to 280 ± 120 μm, p < 0.01) and the control group (153 ± 116 to 179 ± 124 μm, p < 0.01) during follow-up period, the degree of increase was significantly greater in the statin treatment group than in the control group (188 ± 64% vs. 117 ± 39%, p < 0.01). Furthermore, when the patients in the statin treatment group were divided into two subgroups (fibrous-cap thickness