Is myocardial infarction caused by an infection?

No: Well i shouldn't be so definite. Who would have thought that ulcers would be caused by infection. There has been noted to be an increase in heart attacks related to certain infections including those involving the gums, so the cause and effect question has been raised. It has been suggested that inflammation plays a role. But at this time i think most doubt the cause and effect relationship.

Not typical: The heart damage is caused by poor blood flow in diseased vessels around the heart and eventually an obstruction to blood flow to an area of the heart. There is something called viral myocarditis but this would not typically increase your risk for a heart attack.