Serial change and its determinants of residual plaque characteristics under sirolimus-eluting stent: A coronary angioscopic study

ObjectivesTo examine serial change in the residual plaque behind the sirolimus-eluting stent (SES) using coronary angioscopy in patients with SES implantation and to identify its baseline determinants.BackgroundPrevious coronary angioscopic studies have demonstrated that SES enhances the yellow grade of residual plaque during follow-up period.MethodsA total of 42 patients with stable angina pectoris or silent ischemic heart disease, who had a successful SES implantation were examined by coronary angioscopy both at the baseline (SES implantation) and the follow-up period (9–14 month follow-up). The patients were divided into three groups as: worsened group (WS: yellow color grade of coronary plaque at the follow-up period was worsened compared to the baseline period, n = 15), no change group (NP: no change compared to the baseline, n = 16), and improved group (IP: improved compared to the baseline, n = 11). Then, the determinants of the nominal change of yellow color grade were examined by multiple regression analysis.ResultsThe low-density lipoprotein cholesterol (LDL-C) level in IP group at the follow-up was significantly decreased compared to baseline (from 120.0 ± 29.8 mg/dl to 74.3 ± 16.7 mg/dl, p = 0.0005), and was the lowest among three groups (WS: 103.5 ± 16.4 mg/dl, NC: 105.7 ± 18.7 mg/dl, and IP: 74.3 ± 16.7 mg/dl). Multiple regression analysis revealed that family history, statin administration, baseline serum creatinine, baseline ‘in-stent’ thrombus, and follow-up LDL-C were significant determinants to the nominal change of yellow color grade after the SES implantation (p < 0.0001).ConclusionsSerial change in tissue characteristics within residual plaque under SES is determined by several factors, especially LDL-C level as well as statin administration. Adequate management of LDL-C by statins might be crucial for stabilizing residual plaque after SES implantation.