Impact of HMG-CoA Reductase Inhibitors for Non-Treated Coronary Segments

摘要

Background HMG-CoA reductase inhibitors (statin) have been reported to decrease coronary artery events in several angiographic studies. However, the mechanism by which statin achieve this is still unclear. The purpose of this study was to identify the effect of statin on coronary plaque using serial intravascular ultrasound analysis. Methods and Results In this study, 48 patients with 48 lesions were divided into the prescribed group (statin group, n=22) or the non-prescribed group (control group, n=26) after successful coronary artery stenting. IVUS images were obtained at consecutive 5 mm segments, 5 mm from the proximal stent edge, immediately after stenting and at 6 months follow up. External elastic membrane volume (EEMV), lumen volume (LV) and plaque volume (PV) were measured using Simpson's method. The control group revealed no significant serial change in EEMV, PV, and LV during 6 months. On the other hand, the statin group revealed significant reductions of PV (35.5± 12.7 mm~3 vs 30.9±15.6 mm~3, p=0.001), resulting in increase of LV (47.7±19.8 mm~3 vs 52.5±22.2 mm~3, p=0.003) without EEMV change (82.8±21.8 mm~3 vs 83.9±25.7 mm~3, p=NS). Although percent EEMV and percent LV changes showed no differences between the two groups, a larger percent PV change was observed in the statin group compared to the control group (control; 5.8±20.3% vs statin; -20.4±21.8%, p=0.02). Conclusion The results of this study suggest that statin administration for 6 months reduces coronary plaque without positive vessel remodeling.