Thrombolytic therapy and its combination with transluminal catheter dilatation.

The material for complete occlusion of an artery is predominantly thrombotic. The longer the occluded segment the worse are the results of PTA since the thrombotic material is not compressible. As long as this thrombotic material is not already organized, it can be lysed by thrombolytic therapy, and thus removed. Remaining stenoses can be dilated subsequently. Thrombolytic therapy was carried out either systemically, i.e. by intravenous infusion of high doses of streptokinase or by selective local infiltration of an occluding clot with low doses of the same drug via a catheter. This study deals in particular with local low-dose streptokinase therapy. Out of 205 patients treated, primary recanalization was achieved in 145 (75%) and in 107 of these cases additional balloon dilatation was necessary. In 36 patients (25%) reocclusion occurred within the first 2 weeks. Out of the other patients the cumulative patency rate after 2 years was 50%. The combination of PTA with local low-dose thrombolytic therapy has several advantages: It facilitates probing of the occlusion by softening the clot. It removes the lysable component of the clot, giving the possibility of restricting the dilatory procedure to a shorter segment and, thus, diminishing the vascular trauma and risk of rethrombosis. It helps to prevent rethrombosis by the after-effect of thrombolysis. It provokes hyperaemia lasting for 1 to 2 days. It is capable of rapidly dissolving early reocclusion or macroemboli. Local low-dose thrombolytic therapy in combination with PTA has effectively extended the number of non-surgical recanalizations of peripheral arterial occlusions in our clinic.