Lysis of arterial clot by intravenous or intra-arterial administration of streptokinase

Intra-arterial thrombolysis with streptokinase was studied in 38 patients. The indications were peripheral thromboembolism in nine patients (group 1), postreconstruction graft thrombosis in 26 patients (group 2) and renal artery thrombosis in three patients (group 3). The intra-arterial route was used for the first and third groups and in 16 of the second group. The intravenous route was used in the remaining ten patients. Lysis was achieved in all of the group 1 and 3 patients. The latter were also treated with percutaneous transluminal angioplasty after dissolution of thrombus of the renal artery. In group 2 patients, lysis was achieved in eight of 16 patients in whom lytic therapy was instituted within seven days of graft closure. There was no lysis in all ten patients in whom elapsed time was more than seven days. Postlytic angiographic visualization of etiologic mechanisms for thrombosis enabled subsequent successful correction in three of five patients in group 2. Attempts to correct graft failure by surgical treatment when lysis had failed were often unsuccessful (12 of 17). Lytic therapy is most effective for acute embolic occlusion and for thrombosis of less than seven days duration. Although there is no difference in drug efficacy by route of administration, a lesser number of complications (such as, fever and hematoma) occurred with intra-arterial infusion. The effectiveness of lysis is also directly related to the collateral circulation and runoff beyond the occlusion. Lysis is not indicated for severe acute ischemia if surgical treatment is an alternative or if it may cause distal embolism as with complete axillofemoral graft thrombosis. Lytic therapy is least effective for graft thrombosis with pre-existent poor runoff.