Why do sports stars collapse in action?

Chandan Devireddy.

"Testing is very controversial in the medical community as far as what type of testing, when to screen, how to screen," says Devireddy, who works at Emory University Hospital in Atlanta, Georgia.

The Premier League, for example, says all players aged 16-18 at its member clubs "must go through a cardiological examination/screening" and then have follow-ups "as early in their careers as possible and again if the annual medical screen shows any results that warrant a further examination."

That should have covered the 23-year-old Muamba, wh