Inadequate blood flow to the heart muscle typically results from the constriction or obstruction of the coronary blood vessels, which provide nourishment to the heart muscle. This narrowing or blockage is usually due to atherosclerosis, a buildup of fatty deposits on the arterial walls. Myocardial ischemia occurs when the heart muscle doesn’t receive sufficient oxygen, potentially leading to issues like angina pectoris and myocardial infarction, commonly known as a heart attack.