A team of US scientists has discovered that a hole in the heart is not, as was thought, a major caus...
A team of US scientists has discovered that a hole in the heart is not, as was thought, a major cause of strokes.
According to new research from the University of Iowa, having a hole in the upper chamber of the heart, also called patent foramen ovale (PFO), is not as significant in causing stroke in the general population as earlier studies had suggested.
However, more data is needed to determine when PFO - which is found in around one in four people - can lead to strokes.
And the research does not overturn the recommendation to close holes in the hearts of young stroke patients.
Previous studies suggested PFO is a common cause of stroke because it allows blood clots to pass through the heart, bypass the lungs and go to the brain.
But the authors of the US report found that in the majority of patients, PFO and strokes are unrelated.
Particularly in patients who are older than 55, traditional cardiovascular risk factors are more important than PFO in contributing to cryptogenic strokes - those of which the cause is not obvious.
The authors found, however, that in younger patients PFO may play a more important role in causing cryptogenic stroke - and are now calling for a larger population-based study to determine the magnitude and nature of the risk for those patients.
Researchers have struggled to determine the significance of PFO in stroke patients in part because previous studies have involved older patients and have overlooked younger, more active people.
The British Stroke Association estimates that strokes cause more than 67,000 deaths each year in the UK.