Myocardial infarct

Myocardial Infarction means the destruction of myocardial cells due to a lack of oxygen.

If the myocardial cells are not supplied with the necessary oxygen to meet their metabolic demands, then they die.

Thus, a myocardial infarction (a heart attack) occurs when there is not enough oxygen being supplied by the flow of blood. There are two main reasons why there would be a lack of oxygen.

Number One: If the work load of the heart increases, it needs more energy, thus it increases its metabolic demands, and if the blood can not flow fast enough or in enough quantity (essentially the same thing) then there will be a mismatch of demand and supply of oxygen. If this last long enough, the cells will die.

Number Two. If the metabolic demands of the heart remain the same, but the supply of blood is suddently cut off, this will also result in myocardial infarction. In this case, although there is still a greater demand for blood than supply, the reason for this is that the coronary arteries have been clogged, by a thrombus or suddenly closed off plaque.

Health Sciences > Medicine > Cardiology