MR Cheong's hectic life as a legislator may have been one of the things that killed him, according to Queen Mary Hospital's chief of medicine, Professor Chan Tai-kwong. A legislator since 1980, Mr Cheong had suffered no symptoms of coronary heart disease before the fatal attack on Monday evening, soon after giving an exuberant rendition of his favourite song, Unchained Melody, for which Sun Hung Kai Properties and WharfCable were to pay $66,000 into the Hongkong Journalists' Association's fund-raising effort. As well as being a founding member of the new Liberal Party, he was a vice-chairman of the Business and Professionals Federation. Liberal Party colleague Dr Lam Kui-chun said Mr Cheong had never complained, but he must have shouldered great pressure from his political career and industrial business. ''I myself feel very strong pressure as a legislator, so you can imagine what it was like for him,'' he said. Mr Cheong took on many additional duties as a legislator. He was chairman of the group on airport financing, the important Public Accounts Committee and the panel on economic services and public utilities. He also sat on committees dealing with education, manpower, trade and industry and public works. He was also chairman of the council of the Sir Edward Youde Memorial Fund. He was as busy in business as he was in politics. Apart from being managing director of the Lee Wah Weaving Factory and Cheong's Textile, he was a director with a dozen other companies, including Kader Holdings and Kader Industrial, whose Thai toy factory was destroyed last week, killing more than 200 employees. He was chairman of the Hongkong Industrial Estates Corporation Board and the Federation of Hongkong Industries. He was a keen golfer, having played the morning before his death, and as a voting member of the Royal Hongkong Jockey Club, won $1 million in prize money with Lichinsky, owned jointly with colleague Mr Allen Lee Peng-fei. Professor Chan said there were many causes of coronary heart disease - diet, weight, lifestyle and hereditary factors - which could result in a fatal attack. Mr Cheong's medical records showed he had suffered no previous symptoms or heart problems related to the disease, and a check-up two years ago found his heart to be normal. It was not uncommon for patients to have a sudden attack, because signs of an artery blockage could not be easily detected at a preliminary stage, Professor Chan said. ''The attack usually comes as an aftermath of an exciting event - say, vigorous exercise or a party,'' he said. Mr Cheong was leaving a Journalists' Association Ball when he collapsed. Doctors at Queen Mary Hospital yesterday described how they tried to save the legislator's life. Dr Lau Chu-pak, one of four cardiologists who treated Mr Cheong, said he had virtually no blood pressure and his heart had stopped when he arrived at hospital. ''It took us a long time to try to save him at the emergency ward, there was some positive reaction from the patient although it was not very strong,'' said Dr Lau. Mr Cheong was given resuscitation and external heart massage at the emergency ward to maintain his blood pressure while doctors tried to diagnose his illness. Apart from the four cardiologists, Legislative Councillors Dr Lam and Dr Leong Che-hung, who accompanied Mr Cheong to hospital, helped with the treatment. After about an hour, he was transferred to the coronary care unit and later to the Cardiac Catheterisation Laboratory, where emergency heart surgery was performed. Another cardiologist, Dr Stephen Lee Wai-luen, who arrived at about 2 am, said surgery was essential to try to save Mr Cheong's life. It took about 20 minutes to insert a balloon dilatation catheter to remove the clots in his coronary arteries, which had led to a 70 per cent reduction in blood flow to his heart. ''There was no choice for us, we had to re-open his arteries immediately,'' he said. ''A normal person would have no chance of living if his main coronary artery was blocked unless it was reopened immediately,'' Dr Lee said. Surgery lasted for 31/2 hours, during which doctors also injected urokinase, a fluid to dissolve the clot in Mr Cheong's arteries. Mr Cheong was unconscious and supported by a heart-lung machine during surgery. Although the clots were removed successfully within 30 minutes of the surgery beginning, Mr Cheong died because serious damage to his heart had led to failure of the brain and other organs.