The British Heart Foundation (BHF) has criticised the unrealistic way that heart attacks are portrayed by the media. On the silver or plasma screen, victims clutch at their chests as if they've been hit by a sledgehammer. They grimace, drop to their knees, look to the heavens and, finally, crash to the ground like a felled tree.

Then, before they have time to tell their family where their life insurance documents are hidden, their head rolls to one side and they succumb with a terminal sigh.

The BHF wants you to know that real heart attacks usually develop much more slowly and that the symptoms are nothing like as obvious.

Its choice of Steven Berkoff, tough guy actor and playwright, to front its awareness-raising campaign confirms my suspicion that it actually enjoys putting the frighteners on people.

Its current slogan is “Doubt Kills” and I'll bet its next poster features the tear- stained face of a six-year-old and the strapline “Daddy had a twinge in his chest on Sunday and he's dead now...”

If it reckons that actors and directors are the only people who exaggerate the signs of illness, then it ought to spend a day with my patients. They specialise in over-the-top descriptions of every condition known to humankind.

Once in a while I enliven a boring afternoon with a game of “Chorus Line”. As patients describe their symptoms I award marks for style, chutzpah and pizzazz, determining their position in the line-up for the closing number, “One kinda numb sensation, every little step she takes”. Diddely diddely dah.

One fascinating thing about the game is that the potential points tally bears no relation to the severity of the illness. I've sat through depictions of simple sore throats so flamboyant that they made Jim Carey's performance in The Mask look like a masterclass in understatement.

And unless you've seen the tummy cramps and loose poos that define a case of irritable bowel syndrome presented Off-Broadway style by a drama queen who thinks he's trying out for a part in Will & Grace, you ain't seen a case at all.

I am not particularly bothered by this symptomatic show-boating but, like all GPs, I do tend to pay far more attention to patients who kick things off with something like, “I'm sorry to bother you about this...” That's when I know it's possible that I'll soon be treated to a textbook description of the vague abdominal pains and constipation that go with cancer of the colon or the apparently unconnected episodes of weakness and clumsiness that might suggest multiple sclerosis.

The media doesn't always get it wrong. President Jed Bartlet's relapsing MS in The West Wing was right on the money. But for every accurate cinematic portrayal like Stepmom's depiction of chemotherapy or Rain Man's take on life with an autistic savant, there's a schmaltz-fest about facing up to a terminal illness or a lazy misrepresentation of schizophrenia as some sort of “split personality”. You aren't going to learn much about medicine from the movies.

If you insist on subjecting me to your “badly twisted ankle” audition piece in the style of Russell Crowe, then don't be too surprised if I get a bit theatrical myself. I've got dozens of role models, from the self-sacrificing Dr Manson in The Citadel to the insufferable surgeon-turned- sardonic GP Doc Martin.

What's more I can adopt these different personas at will. Depending on whether you're making perfect sense or talking abject nonsense, I can flip in an instant from “caring and concerned” to “cool and sardonic”.

You might say that that makes me a bit Jekyll and Hyde, especially if you studied psychiatry by watching the Classic Movie Channel.

“Tonight, Matthew, I'm going to be Fredric March [the actor who won an Oscar for his portrayal of the character]”. As seen in the scarier 1931 version, obviously.

Dr Copperfield is a GP in Essex. He also writes for Pulse Magazine and pulsetoday.co.uk

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