New figures suggest that more than a million people in the UK are now living with atrial fibrillation, a dangerous heart rhythm. Those affected, like Richard Elgar (pictured above), are at five times greater risk of having a stroke.
This is the first time the figure has passed a million - it has risen nearly 20% in five years. The rise may be due to an increasingly older population, and also better diagnosis. Sometimes there are no symptoms, leaving people completely unaware that they are at risk of stroke.