问题就是有人认为有可能有害处。

quote from wiki: Many experts are deeply concerned that people experiencing a heart attack may attempt to perform Cough CPR before attempting to call for emergency medical assistance first. The action of coughing itself may worsen myocardial ischemia and infarction (i.e. worsen a heart attack) due to the breath holding individuals experience while trying to cough, preventing the inhalation of oxygen.