The Use of Tissue Plasminogen Activator to Declot Arteriovenous Accesses in Hemodialysis Patients

Thrombosis is the most common complication of arteriovenous (A-V) access, resulting in malfunction or total failure. We describe the first use of the thrombolytic agent tissue plasminogen activator (t-PA) to declot the A-V access in 15 hemodialysis patients (14 A-V grafts and one fistula). The t-PA was infused directly into the A-V access in 10-mg doses, at 2-hour intervals, to a maximum of 30 mg. As determined by angiography, t-PA infusion resulted in a dramatic decrease in clot volume in all cases and complete lysis, with return of bruit and thrill, in 10 patients. Eight of the 10 were able to be treated with hemodialysis via the A-V access the following day. In these patients, angiography demonstrated stenosis at the venous end of the A-V access in eight of nine A-V grafts (the one fistula did not have a venous stenosis). Three patients reclotted within 24 hours, and one had bleeding 5 days later after dialysis requiring compression of the A-V access, which resulted in reclotting. Five patients had functioning A-V grafts 1 to 15 months after t-PA treatment (with angioplasty of the venous stenosis required in three of these), and one patient was lost to follow-up. All five patients in whom t-PA infusion was only partially successful had venous stenosis. One patient died before surgery (unrelated to t-PA). Thus, venous stenosis was present in 13 of 15 A-V accesses studied, the highest incidence reported to date. No bleeding occurred at remote sites and only minor local bleeding was noted in five patients, which suggests a lower incidence of bleeding compared with other thrombolytic agents. Although the cost of t-PA is high as compared with streptokinase or urokinase, only 20 mg of t-PA was needed for declotting in 40% of our patients, thus decreasing the cost of therapy significantly. The importance of venous stenosis as a chuse of the A-V access thrombosis, as well as the importance of rapid diagnosis and repair of any vascular defects noted after thrombolysis, is underscored by the data in this study.