In England, Scotland and Wales, patients with angina, valvular heart disease, a heart murmur or heart failure do not have to tell the Driver and Vehicle Licensing Agency (DVLA) and can continue to drive a car a month after an episode as long as their doctor says they are fit to.

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But just before graduating from MIT, he says, a military physical showed that he had a heart murmur, disqualifying him.

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Denman was second in the 2010 Gold Cup and third in the Hennessy after treatment for a heart murmur which had threatened to end his career.

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