[Thrombolytic therapy in acute ischemic stroke. Critical analysis of current knowledge].

Thrombolysis is a highly promising treatment in acute ischaemic stroke. There is evidence of positive effects at least up to three hours and most probably up to six. The risk of intracranial haemorrhage is increased fourfold with thrombolysis; risk factors other than the treatment as such have not been identified for certain; the risk is not related to giving thrombolysis during the 0-3 as opposed to the 3-6 hour time window. There is a non-significant excess of deaths, ranging from a small reduction to a substantial excess. There is not enough evidence to answer several questions regarding the influence of patient- and stroke characteristics on effectsize; death; and risk of intracranial haemorrhage. Giving priority to new large randomized controlled trials is essential to achieve this knowledge.