In a new study published in the online issue of Neurology, researchers claim to have found difference in the left atrium in the hearts of black and white patients, which may play a role in the risk of stroke.
Hoomean Kamel, lead author and Vice Chair for Research and Chief of Neurocritical Care in the Department of Neurology at Weill Cornell Medicine, New York, USA, said, “black US residents face a higher risk of stroke caused by blood clots to the brain, known as ischemic stroke, compared with white residents, yet the difference cannot be entirely explained by differences in known risk factors… the difference is especially notable for strokes where the cause cannot be determined. Better understanding of the underlying causes of these strokes is important for addressing these racial disparities.”
The study involved 2,391 black and white patients who suffered an ischemic stroke. Using electrocardiograms (ECGs) and echocardiograms, researchers looked at the structure and function of the left atrium of the heart.
Researchers, blinded, took measurements of the P-wave terminal force in ECG lead V; they measured the amount of fibrosis, scar-like tissue, in the left atrium and impaired inter-atrial conduction; and using the echocardiogram a diameter was taken of the left atrium. Linear regression was used to examine the association between race and atrial cardiopathy markers after adjustment for demographics, body mass index, and vascular comorbidities.
This study found that the mean diameter of the left atrium for all participants was 3.65 centimetres. The mean for black subjects was 3.58 centimetres, contrasted with 3.69 centimetres in white subjects. Black patients also had more ECG markers of arterial fibrosis.
Researchers claim that these findings show a systemic difference the structure of the left atrium between black and white patients, and clinicians should be aware that structural or functional changes in the left atrium may not present similarly in all stroke populations. They added that more research needs to be done on the different manifestations of cardiac disease and the more appropriate use of drugs which may reduce the racial and ethnic disparities in stroke.
Kamel further commented, “our findings should not be taken to imply that these racial differences in people with stroke reflect innate biological differences… our findings suggest that the current standards for diagnosing left atrial disease that can lead to stroke may need to be updated. These standards were established in groups of exclusively white people and may not fully reflect the variety and complexity of how these acquired cardiac issues are manifested in all people.”