What is Tissue Plasminogen activator (t-PA) and how does it work?
Tissue plasminogen activator (t-PA) is produced endogenously by endothelial cells. It works by converting proenzyme plasminogen to activated enzyme plasmin. Activated plasmin in turn dissolves fibrin clots into LMW fibrin degradation products. It is produced by recombinant DNA techniques for clinical use. Serum half-life is 4-6 min but the half-life is lengthened when bound to the fibrin of a clot. Though the criteria for the administration of a synthetic t-PA (Alteplase) is very stringent, it has been found to assist with dissolving clots that cause acute ischemic stroke. The following information lists the inclusion/exclusion criteria for the administration of IV or IA (intra-arterial) t-PA, as well as the risk factors that are to be considered: Inclusion Criteria (all answers must be YES): Age 18 years or older Clinical diagnosis of ischemic stroke (causing measurable neuro deficit) Time of symptom onset < 3 hours for IV administration (well established) Time of symptom onset < 10 h
