EMBARGOED FOR RELEASE UNTIL 4 PM ET, April 12, 2004
Guideline: Heart Condition Does Not Increase Risk of Second Stroke
ST. PAUL -
A new guideline refutes the current thinking that people with a heart condition called a patent foramen ovale (PFO) who have had a stroke are at greater risk of having a second stroke. The guideline, developed by the American Academy of Neurology, determined that people with a PFO who suffer a stroke with no known cause and receive treatment are at no greater risk of having a second stroke than those who had a stroke and did not have a PFO. The guideline is published in the April 13 issue of Neurology, the scientific journal of the American Academy of Neurology. A PFO is a small opening between the two upper chambers of the heart, or the atria. The opening normally closes shortly after birth, but does not close in up to 25 percent of people. “There was debate within the medical community about whether PFOs should be closed or managed with medication, so we hoped to resolve that question,” said guideline co-author Scott Kasner, MD, of the University of Pennsylvania Medical Center. “We found that there is no evidence to support or refute the role of closing a PFO. More research is needed to answer this question.” The guideline also found that people younger than 55 with both a PFO and an atrial septal aneurysm (ASA) may have an increased risk of a second stroke. An ASA is a bulge in the wall between the atria. It occurs in an estimated five percent of people. Up to 70 percent of people with an ASA also have a PFO. The guideline, which was developed by analyzing all of the scientific research on the topic, also examined the use of aspirin and warfarin to reduce the risk of subsequent stroke. Both aspirin and warfarin reduce the risk of blood clots that can cause stroke. Analysis showed that there is inadequate evidence to determine whether aspirin or warfarin is the better medication to prevent subsequent stroke and death, but that the side effect of minor bleeding is more common with warfarin. According to the guideline, more research is needed, particularly on the effects of an ASA on stroke risk and how ASAs should be managed. “We need to learn more about how these abnormalities in the heart cause stroke,” said Kasner. “It is especially important because the prognosis and treatment may depend on this relationship.” Studies should also be done comparing the results from the use of medications to the use of procedures to close PFOs, the guideline stated. The first author of the guideline, Steven Messé, MD, also of the University of Pennsylvania, said, “Patients with PFO and stroke and the physicians who care for them should feel comfortable participating in research to determine the best treatment, given that the current data are equivocal.” The guideline encourages neurologists to communicate with patients who have had a stroke and are on aspirin or warfarin therapies about their future health risks. The experts agree that patients should know that the presence of a PFO does not necessarily signify an increased risk for subsequent stroke, compared to other stroke patients without atrial abnormalities. Patients with stroke and PFO should consider participating in research to further address this important medical problem, Kasner said.