Patients who suffer a stroke also face significantly higher risks of heart attack or other major cardiovascular events within 30 days of having a stroke, according to new Western-led research. These first-ever findings into the brain-heart connection should signal a change in how health-care professionals treat and monitor stroke patients following their event.
The study, First-Ever Ischemic Stroke and Incident Major Adverse Cardiovascular Events in 93 627 Older Women and Men, was published Jan. 9 in the American Heart Association journal Stroke.
Led by Dr. Luciano Sposato, the Kathleen and Henry Barnett Chair in Stroke at the Schulich School of Medicine & Dentistry, the study showed that women and men with no underlying heart disease are more than 20 times more likely - 23-fold in women, 25-fold in men - to have their first major cardiovascular event following a stroke. These events include things like heart attack, chest pain, cardiac failure or cardiac death.
While this risk dropped after 30 days, men and women who had a stroke still had twice the risk of a major cardiac event than those who didn't up to one year later.
The research team examined Institute for Clinical Evaluative Sciences (ICES) data for more than 90,000 adults over the age of 65 in Ontario with no pre-existing clinical diagnosis of heart disease. The researchers examined the incidence of cardiac events in two groups - a group of just more than 20,000 people who had a stroke and a group of approximately 70,000 individuals without stroke but with similar vascular risk factors, comorbidities and demographic characteristics.
The researchers point out that the connection between cardiovascular events and stroke has often been believed to be the result of shared risk factors like high blood pressure, diabetes or smoking. In this study, however, there was the same proportion of these risk factors in both groups.
"This shows that after taking risk factors into consideration, having experienced a recent stroke was independently associated with the incidence of major adverse cardiac events," said Sposato, Director of the Heart & Brain Laboratory at Western. "This leads us to believe that there are underlying mechanisms linked to stroke that may be causing heart disease."
In a paper published earlier in 2019, Sposato and collaborators used animal models to back up this finding by demonstrating that the brain damage caused by stroke leads to inflammation and scarring in the left atrium of the heart. These changes are well-known structural abnormalities for a number of heart diseases such as heart attacks, heart failure and cardiac arrhythmias.
"This is the first animal model that clearly demonstrates how stroke can influence scarring in the heart. We are excited to continue work in this area to target these influencing factors to prevent heart disease following stroke," said Schulich professor Shawn Whitehead, co-principal investigator of the study in rats.
Sposato hopes this information will inform clinical practice and encourage health-care providers to watch for cardiovascular symptoms in patients who recently had strokes.
"My hope is that neurologists, cardiologists and scientists can work more closely together on this brain-heart connection so that, in the future, we can understand and target the underlying mechanisms to prevent heart disease after stroke," he said.
