Medical Laboratory Scientist (MLS) ASCP Practice Exam

What causes angina?

1. Thrombus formation in arteries

2. Chest pain from inadequate oxygen supply to the myocardium

3. Increased blood pressure in veins

4. Cardiac arrhythmias

The correct answer is: Chest pain from inadequate oxygen supply to the myocardium

Angina is primarily caused by chest pain resulting from an inadequate oxygen supply to the myocardium, which is the heart muscle. This condition typically arises when there is an imbalance between the oxygen demand of the heart and the oxygen supply that the coronary arteries can deliver, often due to narrowed coronary arteries from atherosclerosis. During periods of increased physical activity or stress, the heart requires more oxygen; if the arteries cannot provide enough blood flow to meet this demand, it leads to the chest pain associated with angina. While thrombus formation in arteries may contribute to reduced blood flow, it is the resultant effect of insufficient oxygen delivery to the heart muscle that is the direct cause of angina symptoms. Increased blood pressure in veins and cardiac arrhythmias could potentially lead to other types of cardiac symptoms or complications, but they do not directly cause the chest pain characteristic of angina. Therefore, the primary mechanism behind angina is indeed the inadequate oxygen supply to the myocardium.