Severe pulmonary embolism (PE) was treated with streptokinase in four patients, three men and one woman, age 38 to 72 (mean = 53 +/- 14) years. Before the thrombolytic therapy, all patients had pulmonary angiogram and hemodynamic parameters analyzed. The drug was infused through the distal lumen of the Swan-Ganz catheter at the pulmonary artery trunk. The initial dosage was 250,000 units in bolus and 100,000 units in 24 to 72 hours. The time interval between the symptoms and treatment had ranged from 2 hours to 5 days.

The results are analyzed as follow:

reduction on right atrial pressure, mean pulmonary pressure, pulmonary vascular resistance, an increase in the stroke volume and cardiac output. In two cases we observed total lysis, in one partial lysis and one patient died from severe form of PE and late infusion of SK. Reinfusion of the drug was necessary in one patient that had PE recurrence with reliable final result. Finally, no one had severe bleeding despite the use of the intrapulmonary catheter