What causes intracerebral bleeding after thrombolysis for acute ischaemic stroke? Recent insights into mechanisms and potential biomarkers

The overall population benefit of intravascular recombinant tissue plasminogen activator (rtPA) on functional outcome in ischaemic stroke is clear, but there are some treated patients who are harmed by early symptomatic intracranial haemorrhage (ICH). Although several clinical and radiological factors increase the risk of rtPA-related ICH, none of the currently available risk prediction tools are yet useful for practical clinical decision-making, probably reflecting our limited understanding of the underlying mechanisms. Finding new methods to identify patients at highest risk of rtPA-related ICH, or new measures to limit risk, are urgent challenges in acute stroke therapy research. In this article, we focus on the potential underlying mechanisms of rtPA-related ICH, highlight promising candidate risk biomarkers and suggest future research directions.