Stroke Alert

Intravenous Thrombolysis Is Relatively Safe and Effective in Elderly Patients Up to 6 Hours After Symptom Onset

By Matthew E. Fink, MD,

Interim Chair and Neurologist-in-Chief, Department of Neurology and Neuroscience, Weill Cornell Medical College

Matthew Fink, MD, is a retained consultant for MAQUET.

This article originally appeared in the August 2012 issue of Neurology Alert. It was peer reviewed by M. Flint Beal, MD. Dr. Beal is Anne Parrish Titzel Professor, Department of Neurology and Neuroscience, Weill Cornell Medical Center. Dr. Beal reports no financial relationships relevant to this field of study.

Source: The IST-3 Collaborative Group. The benefits and harms of intravenous thrombolysis with recombinant tissue plasminogen activator within 6 h of acute ischemic stroke (the third international stroke trial [IST-3]): A randomized controlled trial. Lancet 2012;370: 2352-2363.

After results of the pivotal NINDS intravenous thrombolysis (IV rtPA) trial were published in 1995, there has been a gradual extension of the time window from 3 hours to 4.5 hours, based on additional trials (ECASS II and III). However, the very elderly (> 80 years of age) have been largely excluded from studies and the value of IV rtPA in this group, especially for an extended time window (4.5 to 6 hours), was uncertain. IST-3 was organized as an open-label, randomized trial to include those patients who currently did not have a clearly approved indication for IV rtPA (age > 80 and time > 4.5 hours) with a primary outcome measure of the proportion of patients alive and independent at 6 months.

The study included 3035 patients in 156 hospitals in 12 countries, and 1617 (53%) were > 80 years of age. At 6 months, 554 (37%) patients in the rtPA group were alive and independent compared to 534 (35%) in the control group (OR = 1.13, 95% confidence interval [CI] 0.95-1.35, P = 0.181). However, the rtPA group had a higher rate of early complications and early mortality. More deaths occurred within 7 days in the rtPA group, and symptomatic intracranial hemorrhage within 7 days occurred in 7% of rtPA patients vs 1% in controls. Despite these early hazards, the 6-month outcomes favored the administration of rtPA.