A TOP doctor who was under investigation by the Medical Council is considering legal action against the president of the Hong Kong Medical Association (HKMA). This follows a recent decision by the council's Preliminary Investigation Committee (PIC) that the case of Professor Arthur Li Kwok-cheung should not proceed further, and an inquiry into his professional conduct was not necessary. Professor Li is the dean of the medical faculty of the Chinese University, a member of the high-powered executive committee of the Hospital Authority, and was a member of the Education Commission until his recent protest resignation. Last week, Professor Li said he was ''seriously considering'' taking legal action against a number of persons, including HKMA head, Dr David Fang, and Hong Kong College of Cardiology office-bearers Dr T. F. Tse and Dr Cheng Chun-ho. ''My lawyers told me that it appears I might have a substantial claim for damages under the law of tort against these individuals,'' Professor Li said. Dr Fang, in his capacity as president of the HKMA, wrote to the Medical Council in August, saying Professor Li might ''have misconducted himself in a professional respect'' by reportedly expressing in a Chinese magazine ''remarks that are depreciatory of the professional skill, knowledge, or services of another medical practitioner, or other medical practitioners''. Those remarks were allegedly made over the controversial use of artificial heart valves made of ox tissue. Remarks attributed to Professor Li by Next magazine read: ''In the past, using man-made heart valves, patients would have to take anti-coagulants . . . ''Patients would have to be followed up and have blood tests every two weeks to one month, using doctors continuously; doctors can make a living easily; this is called receiving rent. ''Replacement with an ox heart valve does not require follow up, they have no rent to receive; naturally [doctors] would not recommend patients use [the ox heart valve],'' it read. In the letter, Dr Fang suggested such and some other remarks, were ''matters which may lead to disciplinary proceedings, if such had indeed been so said''. The PIC decided the charges were unfounded and the case was dismissed. Professor Li said last week what was reported in Next magazine was ''a slight misrepresentation'' of a press statement he released on March 6. He had then said the attack on a Prince of Wales surgeon over the new technique ''may be the result of professional jealousy''. The Prince of Wales Hospital, the teaching hospital of the Chinese University, was the first in the world to use ox heart valves in a new design. It was later revealed that six out of 12 rheumatic heart patients who had received the valves had died. An independent report found only one death could be directly related to the valve's insertion. Nonetheless, the new technique has sparked controversy in medical circles. The Hong Kong College of Cardiology wrote to the Medical Council in July to complain about the ''extravagant claims and serious allegations'' allegedly made by Professor Li in Next magazine. Professor Li said he was surprised by the complaints. ''I would have thought if you have something that you are not happy with [concerning] a professional colleague, the usual courtesy is to contact the person whom you have worries about and discuss the issue man-to-man. That was not done,'' he said. ''My lawyer thinks people are prepared to hide behind official sounding bodies like the College of Cardiology or the HKMA, thinking: 'You can't sue me','' he said. Dr Cheng, of the Hong Kong College of Cardiology, said he did not think Professor Li had actively sought a dialogue with them. However, Professor Li said it was he who first wrote to the cardiologists after reading numerous press reports that they had invited him for a dialogue when he had received no such invitation. A HKMA spokeswoman said Dr Fang would not comment on the possible legal action by Professor Li. Professor Rosie Young Tse-tse, chairman of the Medical Council, said she could not comment on a disciplinary case handled by the Medical Council.