Three-dimensional morphological response of lipid-rich coronary plaques to statin therapy: a serial optical coherence tomography study

ObjectivePrevious studies have suggested that intensive statin therapy, compared with moderate statin therapy, provided greater reduction of LDL and better protection against major cardiovascular events. However, the exact dose-dependent mechanism of plaque stabilization remains unclear. The aim of this study is to investigate the three-dimensional (3D) response of fibrous caps overlying lipid plaques to statin therapy. MethodsWe applied a novel computer algorithm to investigate the fibrous cap 3D morphological change over time in patients with coronary artery disease. Patients were treated with either atorvastatin 20 mg/day (moderate intensity) or atorvastatin 60 mg/day (high intensity). Optical coherence tomography was performed at baseline, 6, and 12 months. A total of 31 lipid plaques from 21 patients were analyzed. ResultsConventional metrics such as the minimum fibrous cap thickness change between the two treatment groups were not significantly different between the baseline and the 12-month follow-up. In contrast, the 3D metric thin cap (<80 &mgr;m) surface area change between the baseline and the 12-month follow-up showed dose-dependent, significant differences between the statin treatment groups (P<0.001). 3D reconstructions of fibrous caps further indicated that fibrous caps showed diverse (scattered vs. confluent) patterns and could evolve in a complex manner. ConclusionHigh-intensity statin therapy more effectively stabilized fibrous caps at follow-up. The new 3D algorithm provided more comprehensive and detailed information on the changes in plaque phenotype in response to statin therapy.