Thrombolytic therapy for ischemic stroke - A review. Part II - Intra-arterial thrombolysis, vertebrobasilar stroke, phase IV trials, and stroke imaging

Objective: Intra-arterial thrombolytic therapy for carotid and vertebrobasi lar stroke may result in a more rapid clot lysis and higher recanalization rates than can he achieved with intravenous thrombolysis and thus may warra nt the more invasive and time-consuming therapeutic approach. We present an overview of all hitherto completed trials of intra-arterial thrombolytic t herapy for carotid and vertebrobasilar artery stroke including recommendati ons for therapy and a meta-analysis. Furthermore, new imaging techniques su ch as diffusion- and perfusion-weighted magnetic resonance imaging and thei r impact on patient selection are discussed. Finally, phase IV trials of th rombolysis in general and cost efficacy analyses are presented. Data Sources. We performed an extensive literature search not only to ident ify the larger and well-known randomized trials but also to identify smalle r pilot studies and case series. Trials included in this review, among othe rs, are the PROACT I and PROACT II studies and the Cochrane Library report. Conclusion: Intra-arterial thrombolytic therapy of acute M1 and M2 occlusio ns with 9 mg/2 hrs pro-urokinase significantly improves outcome if administ ered within 6 hrs after stroke onset. Seven patients need to be treated to prevent one patient from death or dependence, Vertebrobasilar occlusion has a grim prognosis and intra-arterial thrombolytic therapy to date is the on ly life-saving therapy that has demonstrated benefit with regard to mortali ty and outcome, albeit not in a randomized trial. New magnetic resonance im aging techniques may facilitate and improve the selection of patients for t hrombolytic therapy. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public an d professional education to regard stroke as a treatable emergency. If appl ied more widely, thrombolytic therapy may result in profound cost savings i n health care and reduction of long-term disability of stroke patients.