Nearly half of emergency physicians are reluctant—even resistant—to use recombinant tissue-plasminogen activator (rt-PA) (e.g., alteplase [Activase®, Genentech]) to treat acute ischemic stroke, even in patients at risk, according to a survey by researchers from the University of Michigan Health System and the American College of Emergency Physicians in Dallas. And that’s likely to be an underestimate, they add.
Stroke is the primary cause of adult disability in the U.S and third most common cause of death. Yet only one FDA-approved drug—rt-PA—has been shown to improve stroke recovery. In general, the researchers say, only 1% to 2% of ischemic stroke patients are treated with this therapy. Even in academic medical centers, only 20% of those eligible are treated with intravenous (IV) rt-PA.
The risk of symptomatic intracerebral hemorrhage is a more important determinant of failure to use rt-PA in the ideal setting than concern about lack of efficacy, according to the survey. The highest acceptable risk, most emergency physicians said, was 3.4%, compared with the 6.4% risk found in the National Institute of Neurological Disorders and
Stroke (NINDS) stroke trial and the 1% risk found in most myocardial infarction trials. The respondents accepted the lower risk with thrombolytic therapy for myocardial infarction but were concerned about the higher risk in stroke patients. Nevertheless, superior outcomes were observed with rt-PA despite the increased risk.
Furthermore, the symptomatic intra-cerebral hemorrhage risk associated with stroke treatment appeared to be similar whether it was administered by emergency physicians or neurologists. Emergency physicians have been quite accurate in their ability to diagnose stroke. Still, it is interesting that 30% of the respondents admitted that their decision as to whether or not to use rt-PA was largely a result of their own experience. Given their low frequency of use, logically, the emergency physician’s experience with IV rt-PA for stroke is limited.