Describe how an atheroma may lead to a myocardial infarction.

An atheroma is the deposition of fatty material in the innermost lining of an artery (caused by the process of 'atherosclerosis').
Atheromas have a tendency to rupture and this increases the likelihood of thrombosis occurring within the lumen of the artery.
If the blood clot forms within a coronary artery (an artery supplying heart muscle), this will reduce the blood supply to the heart muscle. Blood supply to the heart muscle contains oxygen and if this supply is restricted, this will eventually lead to a myocardial infarction (death of the heart muscle) when the demand of oxygen from the muscle exceeds the supply.