A victim of a heart attack may collapse and fall into unconsciousness.
Check the victim's breathing and his pulse. If necessary, apply artificial respiration.
If he is conscious, breathing normally and his pulse is going, place him in a comfortable position and loosen clothing at his neck, chest and waist. Try and get him to breathe deeply. If he is unconscious, place him in the recovery position.
Call an ambulance immediately. Keep people who may be crowding over him away, and comfort him. Take his pulse regularly, at 10-minute intervals, and record how long you take it for, until an ambulance arrives.
Warnings of a heart attack include: pain in the chest, sometimes down the left arm and up the left side of the neck; progressive shortness of breath, sometimes accompanied by wheezing; unexplained coughing; swollen feet or ankles, exaggerated in the evening or after activity. If any of these signs are detected, consult a doctor.