Acute myocardial infarction is when there is a blockage in the tubes (or arteries) in your heart that bring blood and oxygen to your heart muscle. This blockage can happen because of many things, like a buildup of fat and cholesterol from unhealthy eating or not getting enough exercise.
When your heart muscle doesn't get enough blood and oxygen because of this blockage, it can cause a lot of pain in your chest (which some people describe as feeling like an elephant is sitting on it). You might also feel short of breath or sweaty.
If someone thinks they are having an acute myocardial infarction, it is important to call for help right away! Doctors and nurses can help unblock the tubes in your heart to get the blood flowing again. It is very important to get help quickly, because the longer you wait to get help, the more damage can happen to your heart.