It is 1am on a balmy night in one of the ritzier enclaves of west London, and at a four-storey Georgian terrace a party is in full swing. In the Philippe Starck-designed kitchen and imposing double-height living room, the thirtysomething guests — City bankers, yummy mummies and trustafarians — are engaged in animated chatter, while some are occupied by a raucous game of Twister. High spirits are buoyed by a plentiful supply of amphetamines and Colombia’s finest white powder. The mood is boisterous.

Then, one of the guests collapses on the floor, clutching his chest. One hour later, 38-year-old Max is in intensive care at St Mary’s hospital, recovering from a severe heart attack. The consultant should be baffled by the spectacle of this seemingly healthy, lithe man in his prime suffering such a dramatic collapse, but he has seen it all before: toxicology reports reveal a high level of cocaine in Max’s blood, the legacy of the rowdy party just a few hours earlier. Max will make a full recovery, but he is told that if he takes the drug again, he could be signing his own death warrant.

It sounds extreme, but ask any doctor at the sharp end of A&E admissions and they will tell you that it is not an uncommon scenario: in recent years, many of Britain’s hospitals have seen a huge increase in what the white coats privately call “cocaine toxic” or “coke strokes”. The symptoms: at the “lighter” end, hallucinations and disorientation; at the severe end, acute chest pains, heart attack and stroke. The link is cocaine use, even if it is just a few cheeky lines at weekends.

Certainly the statistics tell a story: figures published earlier this year by the magazine Druglink show that the number of drug users being admitted to hospital with cocaine overdoses is four times higher than it was eight years ago. At one London hospital, one in three young men attending A&E with suspected heart attacks were cocaine users — as men are more prone to coronary disease, they seem to be most at risk. Other research, published in the medical journal Circulation, suggests that up to 25% of heart attacks occurring in people under 30 may be due to regular cocaine use, instead of the more typical coronary artery disease.

It is familiar territory for the doctors at St Mary’s. Three years ago, a study here showed that more than half of those who turned up at A&E on Friday or Saturday night complaining of chest pains had cocaine in their systems. As one consultant, who did not want to be named, puts it: “We’re a cocaine nation, and while it creates one problem on the streets, we doctors are battling the other front line. You see a guy with chest pains on a Friday night and think, ‘Okay, get the toxicology report.’ Sometimes you can even tell the moment they come through the door.”

People such as Max are, of course, not the most obvious of drug casualties — or menaces, for that matter. He is not on the rampage, beating up police officers or stealing people’s home-entertainment systems to fund his habit. A married father of two, who annually earns close to seven figures in the City, Max’s demeanour had previously radiated the glow of invincibility common to those who have the lot — the wife, the kids, the house, the car and the monster pay packet. He stayed fit and saw his prodigious weekend cocaine and amphetamine use as no more threatening to his health than a few tequila shots after work. “I’m not untypical of the guys I work with,” he says. “I wasn’t an addict. I live a stressful life, and I wanted to get high at weekends. I didn’t see it as a big deal. It was pretty much par for the course.”

The problem, though, is that getting high at weekends can put huge strain on the heart: cocaine, in particular, constricts the blood vessels, raising blood pressure and making the heart work harder. Throw in alcohol and amphetamines, and you have what some doctors believe is a “ticking time bomb of acute cardiac problems”.

One of them, Dr Murray Mittleman of the Institute for Prevention of Cardiovascular Disease at Harvard, was among the first doctors to carry out a large-scale study of the link between cocaine and heart disease. He feels that we are only scratching the surface in terms of establishing the dangers. “We know that taking cocaine significantly increases the risk of heart attack in individuals who are otherwise at low risk,” he says. “There is a magnitude of heart-disease risk associated with cocaine use, but more research is needed.”

Jamie, a 35-year-old management consultant from Manchester, found out the hard way. Last year, he was admitted to hospital with acute chest pains after collapsing in a bar in the fashionable Canal Street area of the city, and discovered he had suffered a stroke. He is now an avowed abstainer from his previous drug of choice. “I would never in a million years have put myself down as at risk from heart problems at a young age,” he says. “There is a history of coronary disease in my family, but we’re talking men in their fifties and sixties. I was all about the gym and healthy eating, but at weekends, I would party hard. That was enough to put my body under strain. At least I got a warning.”

Dr Sue Paterson, a consultant forensic toxicologist at Imperial College London, has noticed the increased prevalence of cocaine in toxicology samples that have come across her pathology table in the past 20 years — particularly since the department has started testing hair follicles, which demonstrate longer-term cocaine use not detectable in blood or urine samples. “Certainly, our capital city is awash with the drug,” she says. “It’s a huge problem across the social spectrum. My experience suggests that, if anything, the statistics concerning usage are an underestimate.”

Max agrees. These days, he still likes to “get high”, but sticks to wine and vodka, in moderation. It’s not easy, because those weekend parties he attends on occasion are still, by and large, a narcotics free-for-all. “The attitude seems to be that I was just unlucky, a blip,” he says. “The coke and ecstasy still get passed round like Smarties.” And in those moments, it seems, the statistics count for little.

National Drugs Helpline; 0800 776600. British Heart Foundation; 0845 070 8070

All names have been changed

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