LOS ANGELES – Barely more than a quarter of all U.S. acute stroke patients eligible for treatment with intravenous tissue plasminogen activator received the drug within an hour after arriving at the hospital, according to a national registry of more than 1,000 U.S. hospitals dedicated to evidence-based stroke care during 2003-2009.
Among the 641 hospitals in the registry that treated at least 10 stroke patients with intravenous tissue plasminogen activator (tPA) within 3 hours of symptom onset, only 7% of the hospitals achieved a door-to-needle time of 60 minutes or less in a majority of their patients, Dr. Gregg C. Fonarow said Feb. 10 at the Annual International Stroke Conference. Currently, as well as during the study period, national U.S. guidelines called for administering tPA to eligible stroke patients within an hour of their arrival at primary or comprehensive stroke centers (JAMA 2000;283:3102-09)(Circulation 2007;115:e478-e534).
The finding that at least some U.S. hospitals do a good job and get tPA to a majority of appropriate stroke patients within an hour of their arrival "suggests there is a critical need for a targeted campaign tailored to increase the portion of patients with door-to-needle times 60 minutes or less, such as the recently launched Target: Stroke initiative by the American Stroke Association [ASA]," said Dr. Fonarow, professor of medicine and associate chief of cardiology University of California, Los Angeles. The results "identify substantial opportunities for improvement in the speed of tPA therapy."
The analysis also showed that the patients who appropriately received intravenous tPA within an hour of hospitalization had a statistically significant, 1.8% absolute reduction in their rate of in-hospital mortality. In-hospital mortality occurred in 10.4% of patients whose tPA dose was delayed beyond 1 hour, but dropped to to 8.6% in patients whose treatment fell within the first 1-hour.
The 1.8% mortality difference "is a big deal, that is clinically relevant and important," Dr. Fonarow said in an interview. Further analysis of the mortality effect showed that after adjustment for possible confounders, every 15-minute reduction in the door-to-needle time for tPA linked with a statistically significant 5% relative reduction in patient in-hospital mortality.
"These findings demonstrate for the first time that shorter door-to-needle times improve the likelihood that acute ischemic stroke patients will survive," Dr. Fonarow said. When he and his associates saw the rate at 27% "we asked what [was going on]. It made us feel we had to launch an initiative" to improve the rate of faster tPA administration.
Target: Stroke, which was launched a year ago, now has about 1,000 U.S. hospitals enrolled. The program currently promotes best practices culled from published reports and expert opinions, such as having designated stroke teams and codes, and having tPA available at the site of the CT scanner so that it can be delivered to a patient as soon as the brain CT image shows the patient is a candidate for the therapy. As a next step, Dr. Fonarow and his associates will systematically assess the practices of the 7% of hospitals that currently do well in timely tPA delivery to identify more steps that appear to drive their success.
Patients who received intravenous tPA within the first hour of arrival also had a significantly higher rate of discharge to a rehabilitation facility and a reduced rate of needing discharge to a nursing facility or another hospital, and significantly fewer tPA complications, including a significant 0.9% reduction in symptomatic intracranial hemorrhages, from a rate of 5.6% in patients who received tPA beyond 1 hour, compared with a rate of 4.7% in those treated within 1 hour. The reduced hemorrhage rate confirmed the safety of faster tPA administration and likely results from a reduced rate of hemorrhagic transformation because of less ischemic damage.
The analysis used data collected during April 2003-September 2009 on nearly 600,000 patients with an acute ischemic stroke admitted to one of 1,259 U.S. hospitals participating in the Get With the Guidelines stroke registry of the American Heart Association and the ASA.
The analysis excluded more than 465,000 patients who did not arrive at one of these hospitals within 3 hours of their symptom onset. Of the remaining 129,431 patients, 25,504 (20%) received intravenous tPA within 3 hours of their symptom onset at 1,082 hospitals in the registry, and this group constituted the focus of the study. Throughout the 6.5 years of the study, the mean door-to-needle time was 79 minutes, with 6,790 patients (27%) receiving intravenous tPA within an hour. During the study period, mean door-to-needle time improved modestly, from 85 minutes in 2003 to 75* minutes in 2009.