Streptokinase Therapy in Acute Major Pulmonary Embolism: Effectiveness and Problems

Abstract

Resolution following streptokinase therapy was most noticeable in patients treated shortly after a single embolic episode, and was least marked in those with recurrent embolism complicated by associated cardiac or pulmonary disease. Of the four patients who failed to improve, two died and two had pulmonary embolectomy and survived.The results suggest that streptokinase therapy is practicable provided that adequate laboratory control is available, and that it hastens early resolution in acute major pulmonary embolism.

Resolution of Pulmonary Embolism

“…The six patients in this group, without chronic disease, who were followed-up for more than six weeks had a mean final defect of about 20%. This obvious improvement in patients with massive pulmonary embolism (which is not as impressive as that reported by Rosenthal (1968)) is comparable to the improvement with streptokinase (Hirsh et al, 1968;Miller et al, 1969) though perhaps spread over a longer interval.…”

Results of Treatment of Experimental Pulmonary Embolism, as Determined By Radioactive Microspheres

“…3) They do not alter blood flow dynamics.22 4) They are not metabolized. 5) They do not increase tissue damage.23 6) The perfusion rate is identical for all lobes of the lung.…”

Resolution of Experimental Pulmonary Emboli with Heparin and Streptokinase in Different Dosage Regimens

“…The principles of thrombolytic therapy have been established by the fundamental studies of Fletcher, Sherry, and Alkjaersig (33,(44)(45)(46)(47)(48) and the thrombolytic agents SK and urokinase have been extensively investigated in both experimental (9-13) and clinical (14)(15)(16)(17)(18)(19)(20)(21) venous thrombosis and pulmonary embolism. However, the optimal dosage regimen of thrombolytic drugs such as SK is still uncertain.…”

“…However, the optimal dosage regimen of thrombolytic drugs such as SK is still uncertain. SK is usually given in a standard high dose regimen which produces and maintains plasminogen depletion (24,25), a therapeutic approach which has two major shortcomings: (a) hemorrhage, which can at times be serious, is common in patients with recent vascular trauma (18,25); (b) if rethrombosis occurs while the circulating plasminogen is depleted, the recurrent thrombus is likely to be resistant to lysis (11). Although rethrombosis may be prevented by the anticoagulant effect of a high titer of fibrin split products, the decline of this titer towards normal is unpredictable and the patient may be unprotected for a variable length of time.…”

“…Thus, although heparin has been shown to be clinically effective (2)(3)(4)(5)(6) and to reduce mortality (7), thrombolytic agents have the potential advantage of producing accelerated lysis of the emboli (8). The use of streptokinase (SK) 1 and urokinase has been investigated in both experimental (9-13) and clinical (14)(15)(16)(17)(18)(19)(20)(21) venous thrombosis and pulmonary embolism, and direct comparisons have confirmed that greater early resolution occurs after thrombolytic therapy than after heparin in both experimental (22) and clinical (21, 23) pulmonary embolism.…”