Outcome of intraarterial urokinase for acute vascular occlusion

Intraarterial urokinase (IAUK) was administered to 33 patients on 40 occasions for the treatment of acute extremity ischemia and long-term patency was assessed. Lysis was successful in 39 of the 40 cases (95%). Occlusive thrombus was cleared in 12 of 13 patients with native artery occlusion (7 complete, 5 partial), 8 of 9 with autologous vein grafts (5 complete, 3 partial), and in all 18 patients with synthetic grafts (17 complete, 1 partial). The primary cumulative patency following successful IAUK was 100% for native arteries and 47% for synthetic grafts at 12 months, and 23% for autologous grafts at 9 months. The difference in rethrombosis rate between autologous vein (67%) and native artery (0%) was significant (p = 0.02) as was the difference between infrainguinal prosthetic grafts (63%) and native artery (p = 0.025). IAUK is most effective for the treatment of native artery occlusion, but is significantly less effective for thrombosed infrainguinal autologous vein or synthetic grafts due to the likelihood of reocclusion, despite the high immediate success rate. For autologous vein grafts, lysis is frequently incomplete and patency rapidly deteriorates regardless of adjunctive therapy to relieve the underlying obstruction.