Low-dose fibrinolytic therapy. Results and new concepts.

The authors report their experience with the first 57 infusions (50 patients) in an ongoing study of local low-dose fibrinolysis for treatment of thromboembolic disease. Complete lysis occurred in nearly half of cases, while some therapeutic effect was demonstrable in more than two thirds. Success seems to be most directly related to the type of vessel infused, with the greatest success seen in vessels with no alternate pathways for egress of the fibrinolytic agent. Chronic fibrin deposits could also be treated with this technique. Since new thrombus formation occurs in a significant percentage of patients during local fibrinolytic therapy, the authors recommend cautious use of concomitant continuous intravenous heparin at a dosage sufficient to maintain the partial thromboplastin time at 1.5 times normal. While fibrinolytic therapy is usually not curative, it frequently facilitates detection of the underlying lesion, permitting definitive therapy.