Intrathrombus administration of tissue plasminogen activator in acute cerebrovascular occlusion

Intraarterial thrombolysis for acute cerebrovascular occlusion has achieved recanalization at a 50-90% rate. Clinical outcome has been unpredictable. The authors sought to test the hypothesis that intrathrombus administration of recombinant tissue plasminogen activator (rt-PA) would improve recanalization rate and to assess the possibility that clinical outcome would be predicted by the extent of collateral flow. Seven patients with acute cerebrovascular occlusion (less than six hours in 6, twenty-four hours in 1) were treated with intrathrombus rt-PA at 1 mg/minute. Examinations were scored on a five-point motor scale. Collateral flow was assessed angiographically. Vessels recanalized in 5 patients, 3 of whom had good outcomes. Vessels failed to recanalize in 2 patients, 1 of whom had good outcome. Good collateral flow was evident in all 4 patients with good outcome and in none of those with poor outcome. Intrathrombus administration of rt-PA is technically feasible. Favorable clinical outcome is more likely in the presence of good collateral flow. In the absence of good collateral flow, ultra-early intervention may be necessary.