Peripheral artery and bypass graft thrombolysis with recombinant human tissue-type plasminogen activator

Recombinant tissue-type plasminogen activator (t-PA) is a DNA-synthesized thrombolytic agent recently approved for clinical trials. We present the results of t-PA infusions in 18 patients with thrombosed peripheral arteries (12 patients) and peripheral bypass grafts (six patients). The duration of occlusion ranged from 1 to 21 days (mean, 6.8 days). Infusions of t-PA were done by way of an intra-arterial approach at a dose of 0.1 mg/kg/hr. All patients demonstrated thrombus lysis angiographically. Fifteen of 18 (83%) had clinical as well as angiographic improvement. Secondary procedures to maintain patency of the arterial segment were required in seven patients. No complications occurred that were related to the t-PA infusion. No significant prolongation of the prothrombin, thrombin, or activated partial thromboplastin times occurred. At the end of t-PA infusion, the mean circulating fibrinogen level was 59% of the starting value. The therapeutic use of t-PA is still in its preliminary stages and the efficacy and safety of this promising agent need to be further established. From our early experience with t-PA, it appears to be safe as well as effective.