Keen ER Identification Could Avert Future Strokes

Each trip to the emergency room could be a chance to squash a future stroke. Irregular heart rhythms that make people more vulnerable to stroke are often diagnosed in the ER, and a substantial number of high-risk patients can be identified there, according to a study in the November print issue of Stroke: Journal of the American Heart Association.

Many patients with the abnormal heart rhythm known as atrial fibrillation (AF) are treated in the ER. Studies suggest that the ER provides a "teachable moment" to change behavior, says the study's lead author, Phillip Scott, M.D., an assistant professor of emergency medicine at the University of Michigan in Ann Arbor.

As an example, a teenager who comes to an emergency room after an alcohol-related motor vehicle collision is likely to be more receptive to efforts to reduce alcohol consumption and the risk of alcohol-related incidents, says Scott.

"Similar strategies to improve stroke prevention should be explored for implementation in emergency departments," he adds.

About one in 20 people with AF will suffer a stroke each year, says Scott. In AF, the heart's two upper chambers quiver instead of beating, allowing blood to pool and clot instead of being pumped to the rest of the body. If a clot then leaves the heart and lodges in an artery in or leading to the brain, a stroke may result.

However, regular treatment with blood-thinning agents -- particularly the drug warfarin -- can reduce this risk by almost 70 percent, Scott says. Current estimates suggest 40,000 strokes could be prevented each year by fully implementing American Heart Association recommended guidelines on AF, he says.

In a review of medical records at teaching hospitals in Cincinnati and Ann Arbor, researchers found that only 40 percent of patients with a history of AF seen in emergency departments were receiving warfarin and 5 percent were receiving warfarin plus aspirin. Twenty-eight percent were taking aspirin alone -- an anti-clotting agent less effective at preventing stroke -- and 27 percent were not taking any stroke prevention therapy. Two-thirds of the patients on warfarin were receiving inadequate doses.

"The data clearly shows that we're not doing a good job of using warfarin to prevent stroke in people who have atrial fibrillation," Scott says. "Identifying, then encouraging people to begin treatment is part of the problem. In this respect, emergency departments occupy a unique position to identify AF patients at risk of stroke and to increase treatment."

Researchers reviewed the records of 78,787 patient visits at three emergency departments during a six-month period. The records revealed 556 patients with a previously diagnosed history of atrial fibrillation before their trip to the emergency department. Two hundred and forty-nine (45 percent) were receiving warfarin or warfarin and aspirin.

In addition to the underuse of warfarin, the review also identified many instances of inappropriate use the medication. Some AF patients shouldn't take the drug. For example, it could cause excessive bleeding in people with liver disease or ulcers. Of the 556 patients with a diagnosed history of AF, 265 (48 percent) were ineligible for warfarin, yet 90 (34 percent) of them were getting the drug anyway.

Among eligible patients receiving the drug, tests found only one-third were getting the appropriate dose. Two-thirds of the inappropriate doses were too low, meaning the drug probably was not protecting the patients against stroke.

"Future work will focus on interventions with the potential to alter patient and physician behavior without requiring significant investments on emergency physician or nursing time -- an important consideration in the busy emergency department environment," Scott says. "Taking advantage of 'teachable moments' can potentially involve only a few simple recommendations or words of advice from a health professional."

Interactive computer programs and Internet-based patient education programs also have shown promise, he notes.

The number of patients with AF is expected to rise from the current estimate of 2.2 million individuals to 5.6 million by the year 2050, the researchers say.

Co-authors are Arthur M. Pancioli, M.D; Lisa A. Davis, R.N., M.S.N.; Shirley M. Fredericksen, R.N., M.S.; and John Eckman.

Editor's note: For more information on stroke, visit the American Stroke Association Web site: http://strokeassociation.org