Myocardial infarction
As soon as a person thinks they may be having signs of a heart attack, they should call emergency service right away. (Emergency services can be reached dialling 911 in the US, and 112 in most of continental Europe) However, the average person waits about three hours before asking for help. When a person waits to get help, they are more likely to have more serious damage to their heart. The American Heart Association says "time is muscle": the more time a person waits to get treatment, the more heart muscle dies.