Abstract 4714: Differential Response to Comparator Drug Eluting Stents in the Diabetic Rabbit Model
Introduction: Drug Eluting Stents (DES) have become the standard of care for patients with diabetes mellitus undergoing percutaneous coronary intervention yet little is known about the vascular responses to DES in this population. In addition, it remains unknown whether stents eluting sirolimus or paclitaxel are superior in terms of intimal suppression and healing.
Methods: We created an Alloxan-induced model of diabetes in the New White Rabbit. Two week after diabetes induction animals were randomized to receive bare metal (BMS 3.0 × 12 mm-Vision Abbott Vascular), Cypher (3.0 × 13 mm, Johnson and Johnson), Taxus Liberte (3.0 × 12 mm (Boston Scientific), or Xience V (3.0 × 12, Abbott Vascular) DES. Animals were sacrificed 28 days later for light microscopy and scanning electron microscopy. Daily blood sugar was checked on all animals for the duration of the study and they were treated with 1–2U of insulin if levels were >400 mg/dl.
Results: Average daily blood sugar did not differ between DES groups (table⇓). All DES significantly reduced intimal thickness compared to BMS to a similar degree. % fibrin tended to be higher with Cypher and Taxus Stents while intimal inflammation was significantly higher in Cypher and Xience V versus Taxus and BMS. The number of uncovered struts was significantly greater in all DES compared to BMS with Xience V demonstrating the least number of uncovered struts by light microscopy. Similar pattern of healing between DES was seen in SEM analysis for above strut % coverage (BMS 95%±5; Cypher 46%±19; Taxus 58±16; and Xience V 89±5, p=0.0002).
Conclusions: This is the first preclinical study of comparator DES in insulin dependent model of diabetes mellitus. All DES suppressed intimal formation compared to BMS to a similar extent. Signs of delayed healing were seen in all DES compared to BMS. Cypher and Xience demonstrating significantly greater intimal inflammation scores consisting mainly of giant cells compared to BMS and Taxus