Abstract 14332: Characteristic Features of Neointima and Thrombosis of Everolimus-Eluting Stent 10 Months After Implantation: Intravascular Ultrasound and Angioscopic Studies Comparing With Sirolimus and Paclitaxel-Eluting Stents
Background: It has been expected that a second generation drug-eluting stent (DES), everolimus-eluting stent (EES) might have a less frequency of in-stent restenosis rate and very late thrombosis compared to the previous types of DES. This study was to perform a comparison of sirolimus-eluting stent (SES), paclitaxel-eluting stent (PES) and EES with intravascular ultrasound (IVUS) and angioscopy in terms of the degree of neointima formation and the prevalence of thrombosis at a follow-up period. The degree of neointima formed was classified into 5 grades (0: none, through 5: complete endotherialization).
Method: At 8 to 12 month (9.6 month average) follow up, a total of 55 coronary stented lesions (SES 16, PES 24 and EES 15) in 55 patients with coronary artery diesease were imaged with IVUS and angioscopy. IVUS showed that no visible neointima was detected in any SES and EES cases, whereas significant neointima was confirmed in 5 PES cases (21%). Angioscopy revealed that grade 1 neointima was observed most frequently in SES and EES (average grade: 0.73, 0.66, respectively, ns : SES vs. EES). However, grade 2 neointima was most frequently depicted in PES (average grade: 2.1, p<0.05 vs. SES and EES). Red thrombus was identified in 4 SES (25%), 5 EES (33%, p<0.05 vs. SES) and 9 PES cases (38%, p<0.05 vs. SES and EES). Yellow neointima was observed in 4 SES(25%) and 4 EES cases(27%, ns vs. SES), while all PES cases had white neointima. In summary, the degree of neointima offered SES=EES<PES; the prevalence of in-stent red thrombus, SES<EES<PES; the degree of instabilization of neointima probably due to lipid accumulation, SES=EES>PES.
Conclusion: EES had a similar degree of in-stent neointima and higher prevalence of in-stent red-thrombus, compared to SES, although these data were better than PES. Furthermore, EES provided a similar possibility for having instabilization of neointima compared to SES. These basic features of EES especially characterized by coronary angioscopy should be taken into account when following up EES-implanted patients.
- © 2011 by American Heart Association, Inc.