Onset-to-reperfusion time increases mortality in ischemic stroke patients

This meta-analysis (an analysis of data combined from several similar studies) examined how onset-to-reperfusion time (ORT) affects mortality.

The cause of ischemic strokes is a blockage of an artery supplying blood to the brain. The major goal of ischemic stroke treatment is reperfusion (opening the occlusion and restoring blood flow). Reperfusion can be achieved by dissolving the clot causing the obstruction, either with medications (such as tPA; tissue plasminogen activator), or by catheterization (insertion of a small wire into the occluded artery).

It has been determined by numerous studies that the onset-to-treatment time (OTT – which means the time between the beginning of stroke symptoms to the initiation of treatment) affects prognosis, with increased OTT related to worse outcomes.

Since nowadays medical imaging can verify reperfusion during treatment, onset-to-reperfusion time (ORT; the time from the beginning of stroke symptoms and until blood supply restoration is proven by imaging) has emerged as a new treatment goal. The effect of ORT on the functional outcome of patients (the level of disability remaining after treatment) has already been shown, but the effect of ORT on mortality has not yet been published.

7 studies, with a total of 480 patients treated for blockage in a major cerebral artery (one of the major arteries leading blood to the brain) were included in this meta-analysis.

Results showed that the mortality rate increased with increasing ORT. The risk for all-cause mortality (death from any reason) increased by 21% with each 30-minutes that passed until reperfusion was achieved.

Increased ORT was also associated with a similar increase in the rate of intracerebral hemorrhage (bleeding into the brain).

ORT affects mortality and the risk of intracranial bleeding after treatment. Early identification of stroke symptoms and early reperfusion treatment significantly reduced the risk of mortality.

Any patient exhibiting stroke symptoms should receive treatment as soon as possible, to reduce the risk of mortality and reduce long term disability.