What is the long-term risk of a stroke after a heart attack?

This paper studied the long-term risk of stroke in patients who have survived a heart attack. Patients were at increased risk of a stroke up to 30 years after a heart attack. 

After a heart attack, about 2 to 4 in 100 patients have a stroke (not enough blood supply reaching the brain). A stroke can be ischemic (blockage of blood vessel) or hemorrhagic (bleeding into or around the brain). Many common treatments following a heart attack (such as aspirin or treatments the block the blood from clotting) can increase the risk of hemorrhagic stroke, in particular.

Thanks to new treatments, patients are now surviving for long periods of time following a heart attack. It is therefore important to understand the long-term risk of stroke in these patients.

This study examined the records of 258,806 patients who had a heart attack and 1,244,773 similar patients who did not have a heart attack. They were followed for up to 30 years.

After 30 years, the chance of an ischemic stroke was 12.6% for those had a heart attack and 11.9% for those who did not have a heart attack. In the 30 days following a heart attack, patients were 31.9 times more at risk of an ischemic stroke than those who did not have a heart attack. In the first year after a heart attack, patients were 3.1 times more at risk of an ischemic stroke.

After 30 years, the risk of an intracerebral hemorrhage (bleeding into the brain) was 1.2% in those who had a heart attack and 1.6% in those who did not have a heart attack. This was because death rates were higher among those who had a heart attack. In the 30 days following a heart attack, patients were 21.8 times more at risk of an intracerebral hemorrhage.

After 30 years, the risk of a subarachnoid hemorrhage (bleeding around the brain) was low. 0.24% of those who had a heart attack and 0.29% of those who did not have a heart attack had a subarachnoid hemorrhage. In the 30 days following a heart attack, the patients were 16.6 times more at risk of a subarachnoid hemorrhage. 

The authors concluded that there is an increased risk of stroke in the first year after the heart attack. There is an increased risk of ischemic stroke in the 30 years after a heart attack. 

Talk to your doctor on how you can reduce your risk of stroke.