SPONTANEOUS REPERFUSION OF CEREBRAL INFARCTS IN PATIENTS WITH ACUTE STROKE - INCIDENCE, TIME-COURSE, AND CLINICAL OUTCOME IN THE COPENHAGEN STROKE STUDY

Objective: To determine the incidence, time course, and clinical importance of spontaneous reperfusion of cerebral infarcts in patients with acute stroke. Design: Prospective, community based. Setting: Department of Neurology, Bispebjerg Hospital, Copenhagen, Denmark. Patients: Included in the incidence and time course study were 354 unselected patients with acute ischemic stroke. Clinical outcome was studied in a subgroup of 36 patients admitted on the day of stroke onset and in whom it was known whether spontaneous reperfusion occurred within the first week after stroke onset. Measurements: Computed tomography and single photon emission computed tomography, with technetium Te 99m exametazime used as a flow tracer. The Scandinavian Stroke Scale neurologic score was determined on admission, 1 and 2 weeks after stroke, and at discharge. Results: The incidence of spontaneous reperfusion was 77% in patients with cortical infarcts. The frequency of reperfusion increased rapidly from zero at the time of onset to 60% on day 7 after stroke, reaching a maximum on day 14, at which time 77% showed reperfusion. Marked clinical improvement was observed in patients with spontaneous reperfusion (P=.001),while no improvement occurred in patients without reperfusion. Reperfusion was not observed in subcortical infarcts. Conclusions: The rate of spontaneous reperfusion increases gradually with time and occurs within the first 2 weeks after stroke onset in approximately four of five patients with cortical infarcts. Spontaneous reperfusion seemed to improve clinical outcome.