STUDY OF FEASIBILITY AND SAFETY OF A SINGLE AND DUAL DRUG ELUTING BIOABSORBABLE MAGNESIUM ALLOY STENT COMPARE WITH COBALT CHROMIUM SIROLIMUS ELUTING STENT IN PORCINE CORONARY ARTERIES
Abstract:
Background : This experimental nonrandomized prospective self-control study in the animal model was designed to assess the feasibility and safety of single(paclitaxel) and dual drug eluting (paclitaxel and sirolimus) bioabsorbable magnesium alloy stents compared with a single drug eluting(sirolimus), non-bioabsorbable, cobalt chromium stent in porcine coronary arteries. Method : Ten healthy pigs were divided into two groups. Both groups underwent stent implantation in coronary arteries. One group had a single drug eluting (paclitaxel) bioabsorbable, magnesium alloy stent (Propulxar I) compared with a single drug eluting(sirolimus), non-bioabsorbable, cobalt chromium stent (ProNOVA XR) and the other group had dual drug eluting (paclitaxel plus sirolimus) bioabsorbable, magnesium alloy stent (Propulxar II) compared with ProNOVA XR stent. Aspirin 300 mg/day and clopidogrel 75 mg/day were administered after stenting.The groups were then followed up at 1, 2 and 3 months by coronary angiogram and optical coherence tomography(OCT). Histopathological evaluation was also done after the animals were euthanized by a lethal dose of KCL under general anesthesia at 1,2 or 3 months. Results : All stents were excellent in overall performance (deliverability, vessel-preserved curvature, inflation and deflation technique). Angiographic success without procedure-related complications within 24 hours was noted in all cases. Endothelialization of all stents were nearly complete at 1 month and complete endothelialization was found at 2 months. No stent thrombosis was found. Additionally, partial degradation (less than 50%) was obviously found after 3 months. Propulxar II stents were safer and more efficacious when compared to Propulxar I stents in terms of myocardial infarction (0% vs 20%), inflammation score of vessels, injury score of vessels and percent stenosis of vessels (36% vs 59%) and comparable with single drug eluting (sirolimus), non-bioabsorbable, cobalt chromium stents (ProNOVA XR) in terms of myocardial infarction (0% vs 0%) and percent stenosis of vessels (36% vs 39%). Conclusion: In healthy porcine coronary arteries, the feasibility, efficacy and safety of dual drug eluting(paclitaxel and sirolimus) bioabsorbable, magnesium alloy stents (Propulxar II) seem to be better than single drug eluting (paclitaxel) bioabsorbable, magnesium alloy stents (Propulxar I) and comparable to single drug eluting (sirolimus), non-bioabsorbable, cobalt chromiumstents(ProNOVA XR).