
The number of patients who had a heart attack or died within 30 days of surgery were similar in both groups, but 4.6 per cent of the aspirin group had significant bleeding after surgery compared with 3.7 per cent in the placebo group.
Melbourne anaesthetist Kate Leslie, who led the Australian part of the study, said the findings indicated that in most cases patients should stop taking aspirin before surgery.
Other studies had shown aspirin could reduce their risk of heart attack or stroke, but doctors had been uncertain about its effects around surgery.
''When they come to hospital we have not been sure whether to stop aspirin to prevent bleeding or continue it to prevent heart attack or stroke,'' Professor Leslie said.
A related study also published in the New England Journal of Medicine found another drug, clonidine - used to treat high blood pressure and pain - also showed no benefit in preventing heart attacks after surgery. Instead it increased patients' risk of heart attack.



Comment: Meet other world's greatest serial killers:
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