Angioscopy study from a large patient population comparing sirolimus‐eluting stent with biodegradable versus durable polymer

Abstract

This study aimed to compare the neointimal coverage (NIC), subclinical thrombus, color of plaque underneath the stent at 9-month after implantation of sirolimus-eluting stent (SES) either with durable or with biodegradable polymer (BDPM). A total of 175 patients were assigned as Cypher (n = 81, 97 stents with durable polymer) and Excel (n = 94, 112 stents with BDPM) stent at 9-month after indexed procedure. NIC was classified from grade 0-3. Color of plaque was divided into white, light-yellow, yellow, and dark yellow. Thrombus was diagnosed as white or red material with cotton-like or ragged appearance. Incomplete NIC (grade 0/1) circled by a blush was termed by "inflaming." There were significant differences in unstable angina (90.5 vs. 52.4%, P = 0.015), previous myocardial infarction (33.3 vs. 4.0%, P = 0.045) and left ventricular eject fraction (55.2 ± 7.8 vs. 62.6 ± 6.3%, P = 0.021) between the Excel and Cypher groups. The minimal- and maximal-NIC grades in the Cypher group were 0.67 ± 0.58 and 2.29 ± 0.46, respectively, when compared with 1.45 ± 0.67 (P < 0.001) and 2.64 ± 0.49 (P = 0.023) in the Excel group. The percentage of yellow plaque, thrombus, "inflaming" and NIC grade of 0 in the Excel and Cypher groups, respectively, were as follows: 8.0 vs. 26.8% (P = 0.031), 9.8 vs. 32.9% (P = 0.024), 8.0 vs. 38.1% (P = 0.017), and 38.1 vs. 0% (P < 0.001). Of the stents with "inflaming," 63.6% had thrombus when compared with 20.1% of the non-erosion stents (P < 0.001). Overlapping segments had the lowest NIC grades and more "inflaming" demonstrating a significant difference between Cypher vs. Excel stents. NIC grade was positively correlated with thrombus. SES with BDPM has improved NIC resulting in less yellow plaque, thrombus, and "inflaming." Overlapping segments had the lowest NIC grade and more "inflaming."