Final answer:
Coronary artery disease occurs when plaque builds up in the coronary arteries, reducing blood flow to the heart muscles. This can cause a condition called ischemia and, if left untreated, can lead to a heart attack.
Step-by-step explanation:
Coronary artery disease (CAD), also known as coronary heart disease (CHD), is a condition where plaque builds up in the coronary arteries, which supply oxygen to the heart muscle. The plaque buildup can reduce blood flow to the heart muscles, leading to a condition called ischemia, where the cells receive insufficient amounts of oxygen, called hypoxia. If left untreated, coronary artery disease can lead to a heart attack.