Hearts Love Aspirin and Warfarin

Warfarin and aspirin equally effective in preventing stroke and death in heart failure patients

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Heart failure patients often take medication to lower their risk of stroke, hemorrhage or dying. A common choice is warfarin (Coumadin), though a large clinical trial has found that cheaper over-the-counter aspirin may be just as effective.

Researchers conducting the 10-year Warfarin and Aspirin for Reduced Cardiac Ejection Fraction (WARCEF) trial determined that among heart failure patients with normal heart rhythm, neither aspirin or warfarin was superior.

"Talk to your cardiologist about the best way to lower your stroke risk."

Shunichi Homma, MD, associate chief of the cardiology division at Columbia University Medical Center/NewYork-Presbyterian Hospital, said that since the overall risks and benefits are similar for aspirin and warfarin, patients and doctors are free to choose the treatment that best meets their medical needs.

Given the convenience and low cost of aspirin, however, he expects many will take that route.

In addition to being more expensive and available only by prescription, warfarin requires regular monitoring through blood tests and can react with certain foods and medications.

Warfarin thins the blood while aspirin prevents the blood from clotting.

Heart failure patients have a weakened heart and usually take the medications to reduce their risk of blood clots, which can lead to a potentially fatal stroke.

During the long-term WARCEF trial, investigators launched the largest double-blind comparison of aspirin and warfarin so far. They included 2,305 heart failure patients at 168 medical centers in 11 countries. All patients were instructed to take a pill from each of two bottles they received. One was labeled aspirin, and the other warfarin. Only one of the pills was an active medication.

They found that the combined risk of stroke, cerebral hemorrhage or death was 7.5 percent for patients taking warfarin compared to 7.9 percent in patients taking aspirin. The difference was not considered statistically significant.

Those taking warfarin had a lower stroke risk of 0.7 percent compared to 1.4 percent in patients taking aspirin. But warfarin patients were also at twice the risk of major bleeding at 1.8 percent versus 0.9 percent in aspirin patients. Those findings effectively canceled each other out, meaning both had similar risks.

In patients followed for at least four years, evidence suggested warfarin may be more effective in lowering the risk of stroke, intracerebral hemorrhage or death.

An additional analysis is planned to evaluate that evidence and to determine if certain patients would do better with one medication over the other.

Previous research has suggested that warfarin was superior to aspirin in preventing stroke in patients that also had atrial fibrillation, a common heart arrhythmia.

"With at least 6 million Americans — and many more around the world — suffering from heart failure, the results of the WARCEF study will have a large public health impact. Patients and their physicians now have critical information to help select the optimum treatment approach.

The key decision will be whether to accept the increased risk of stroke with aspirin, or the increased risk of primarily gastrointestinal hemorrhage with warfarin," says Walter Koroshetz, MD, deputy director of the National Institute for Neurological Disorders and Stroke, part of the National Institutes of Health.

The study, funded by by the National Institute for Neurological Disorders and Stroke, was published in the May 2 issue of the New England Journal of Medicine.

Reviewed by: 
Review Date: 
May 3, 2012
Last Updated:
May 3, 2012