Stroke Stroke Prevention

High Risk of Stroke Shortly After a Heart Attack

Those who survive a heart attack have an exceptionally high risk of suffering a stroke within the first month of recovery, a new study warns. The results came as a shock to the researchers, who expected that successful methods used to protect against further heart trouble would also offset the risk of stroke. The two diseases share many similar causes.

"This is not the finding we anticipated," said Dr. Veronique Roger, a Mayo Clinic cardiologist who led the study.

The results, which were recently published in the Annals of Internal Medicine, do not undermine the use of current heart disease treatments, Rogers is quick to point out. There has been considerable progress in keeping people alive after a heart attack with the rate of heart failure and second heart attacks showing steep declines.

Although the reasons for the higher risk of stroke are still unclear, Rogers says that one explanation may be that the doctors and patients did not do enough to keep heart problems in check.

"How aggressive were doctors in implementing medications, and how faithful were patients in taking them?" she asked. "We don't know yet," Rogers continued, adding that she and her colleagues are pursuing those questions in further studies.

In determining stroke risk following a heart attack, Roger's team reviewed the medical records of 2,160 patients who were hospitalized at the Mayo Clinic in Rochester, Minnesota between 1978 and 1998. After successful treatment for a heart attack, 273 people went on to suffer a stroke over the six years they were followed.

A high proportion of these strokes occurred within the first month of the heart attack, accounting for a 44-times greater risk than what is expected normally. The risk for stroke remained higher than expected for the next three years.

Rogers says that aggressive treatment should still be a priority. "The sooner you get treated for a heart attack, the better," she said.

But she suggests that doctors may want to reconsider using blood thinning drugs, like warfarin, after a heat attack. There are concerns about using such medications because of bleeding risks. Still, they are one of the few treatments to show a clear benefit for preventing further heart attacks, as well as stroke.

"You would have to balance the concern of stroke with the risks of bleeding," she said.

What matters most, Rogers added, is sticking to the treatment and lifestyle changes that can keep heart disease under control.

"These are lifelong measures that work," she said.