A millionaire investment banker died after bingeing on cocaine and heroin following a slide into depression blamed on the credit crunch, an inquest heard today.

Thomas Sabour was found in his Mayfair flat after taking substantial quantities of the drugs. His girlfriend claimed it was not unusual for him to drink four bottles of vodka a night, and that from time to time he would take heroin.

The hearing in Westminster was told the 44-year-old was born in Tehran, was educated in the US and had a law degree from the Columbia Law School.

He was a successful lawyer and had built up a practice in New York before coming to London in 2006 and was managing director of AKN Investments whose offices are in Berkeley Square.

He was described as a sociable man with many friends and a keep-fit fanatic who ran between five and seven miles every morning and attended two-hour exercise classes every evening.

His drive and obsession with image also caused him to take muscle building drugs, on top of the recreational substances he often used.

Coroner Paul Knapman said Mr Sabour's mother died three years ago and her death had changed his behaviour. He was said to have nobody close to him and his doctor prescribed him medication after he went to him with concerns about losing money on the stock markets following the global financial crash.

Mr Sabour's girlfriend Kyara Dekker told the hearing she had been living with him for some time and that he often took cocaine on a daily basis. She said that on the day of his death, 15 February, he had taken heroin before they had left for a service at a church near his flat.

She said: “We came back and he was very tired, he could barely walk up the stairs. I realised there was something seriously wrong and called 999.”

When ambulance workers arrived they found the banker dead. A statement from his GP said he had spoken about losing money on the markets and had given him pills for depression.

Detective Sergeant Peter Bartlett said there was no suicide note in the flat. Drugs, prescription and Class A substances, were found in the kitchen. A post-mortem examination found there was cocaine and morphine in his system and that part of his heart had become enlarged. This abnormality, together with the amount of cocaine, said to be above normal recreational range, found in Mr Sabour's system had contributed to his death.

Recording a verdict of death from a dependence on drugs, Dr Knapman said: “I think it is true to say he was obsessed about his body image and exercise, that is perfectly clear. It also appears that he had been taking drugs in recent times because he felt himself under considerable pressure.

“He was with his girlfriend when she went back into the bedroom and found him. She called emergency services, it was quite clear he was dead. Kyara Dekker had been staying there and knew that from time to time he would drink substantial amounts and abuse cocaine and opium and on that day she believes he had some opium. Cocaine can and does have a bad effect on the heart and it is quite a significant cause of death in men of a young age in this area of London. I think the evidence is that he was taking drugs, that he was dependent on drugs and that is my verdict.”

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