title: Beneficial effect of aspirin in maintaining the patency of small-caliber prosthetic grafts after thrombolysis with urokinase or tissue-type plasminogen activator.
abstract: Despite successful thrombolysis of occluded prosthetic grafts, rethrombosis remains a problem. We investigated the efficacy of aspirin in maintaining patency of polytetrafluoroethylene grafts (3 mm X 3.5 cm) in canine femoral arteries after thrombolytic therapy. After induction of thrombosis, either tissue-type plasminogen activator (t-PA) or urokinase (UK) was infused just proximal to the thrombus (4000 U/min) until complete thrombolysis was achieved. Five of the 10 UK-treated dogs and five of the 10 t-PA-treated dogs received aspirin immediately after recanalization, and aspirin was continued (325 mg/day) for 4 weeks or until occlusion occurred. A systemic aspirin effect was confirmed by marked depression of serum thromboxane B2 and absent platelet aggregation. Only two of the 10 grafts in the aspirin-free group remained patent for 4 weeks. The remaining eight grafts had all reoccluded by 2 weeks. None of the 10 grafts in the aspirin-treated group reoccluded during the 4 weeks. This significantly improved patency (p less than .001) in the aspirin-treated group was observed equally in grafts treated with t-PA or UK. Thus aspirin is a potent agent in preventing rethrombosis after thrombolytic recanalization of prosthetic grafts.
mesh_terms: D000818:Animals; D001241:Aspirin / Q000627:therapeutic use*; D001807:Blood Vessel Prosthesis; D004285:Dogs; D006083:Graft Occlusion, Vascular / Q000188:drug therapy*; D010974:Platelet Aggregation / Q000187:drug effects; D011138:Polytetrafluoroethylene; D013927:Thrombosis / Q000188:drug therapy*; D013929:Thromboxane B2 / Q000032:analysis; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014568:Urokinase-Type Plasminogen Activator / Q000627:therapeutic use*
chemical_list: D013929:Thromboxane B2; D011138:Polytetrafluoroethylene; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator; D001241:Aspirin