There is an email doing the rounds again that I first saw some time ago. This time there is a powerpoint presentation with some comic pictures, but the information is just as bad as the text emails.
The text varies between emails but the general idea is:
How to survive a heart attack when alone. Without help the person whose heart stops beating properly and who begins to feel Faint, has only about 10 seconds left before losing consciousness. However, these victims can help themselves by coughing repeatedly and very vigorously. A deep breath should be taken before each cough, and the cough must be deep and prolonged, as when producing sputum from deep inside the chest. A breath and a cough must be repeated about every two seconds without let up until help arrives, or until the heart is felt to be beating normally again. Deep breaths get oxygen into the lungs and coughing movements squeeze the heart and keep the blood circulating.
If you receive this email then just delete it. Do NOT forward it on, or try and use this technique if you think are suffering from symptoms of a heart attack.
For more information see UK Resuscitation Council Statement on "Cough CPR"