Abstract 11800: ABSORB Cohort B Trial: Two Year IVUS and IVUS-VH Results of the ABSORB Bioresorbable Everolimus Eluting Vascular Scaffold
Background: The ABSORB Cohort B trial is a continuation of the ABSORB Cohort A trial in the assessment of the safety and performance of a modified ABSORB Everolimus Eluting Vascular Scaffold (Abbott Vascular, Santa Clara, CA, USA). The ABSORB Cohort B trial enrolled 101 patients at 12 sites in the European and Asia Pacific regions between March and November 2009.
Methods: The patients of the ABSORB Cohort B trial were divided into 2 groups, Group B1 (45 patients) with imaging follow-up at 6 months and 2 years and Group B2 (56 patients) with imaging follow-up at 1 and 3 years.
Results: In Cohort B, clinical data up to 1 year for the full cohort of 101 patients (Group B1 and B2) are currently available. In these 101 patients, 1 year clinical results showed an ID-MACE rate of 6.9% with no scaffold thrombosis events. At 6 months, the IVUS results from Group B1 showed limited intra-scaffold neo-intimal hyperplasia. The vessel area remained comparable between baseline and 6-month follow-up (14.22 vs. 14.49 mm2) suggesting the absence of significant expansive or constrictive remodelling. By IVUS-VH, the polymeric scaffold struts were detected as areas of apparent Dense Calcium (DC) and Necrotic Core (NC). The change in quantitative analyses of these areas between implantation and follow-up was used as a surrogate assessment of the chemical and structural alteration of the polymeric struts. The IVUS-VH assessments were similar between baseline and 6 months. At 1 year, the IVUS results from Group B2 showed limited intra-scaffold neo-intimal hyperplasia. Over time there was a modest but significant increase in total plaque area with a concomitant increase in vessel area. The serial IVUS-VH assessments revealed a significant decrease in DC while the two other histological components (fibrous and fibro-fatty) increased significantly.
Conclusion: At 1 year, by IVUS, there was no scaffold area reduction, non significant lumen reduction and minimal ne-ointimal hyperplasia. IVUS-VH showed minimal early signs of strut resorbtion at 1 year. Two year data are currently being collected and we will present 2-year IVUS and IVUS-VH results for the Group B1 of 45 patients from the ABSORB Cohort B trial.
- © 2011 by American Heart Association, Inc.