A blocked coronary artery is incredibly dangerous. Dr. Yuba Acharya, Interventional Cardiologist, describes the symptoms of a blockage.

"The most common symptom is angina. Angina is chest pain or tightness. When you're working out, you're exerting, you get this chest tightness sensation, could be shortness of breath as well," Dr. Archarya said.

According to Dr. Acharya, the most common cause of the artery blockage is cholesterol plaque.

"It's mostly cholesterol combined with calcium, as well as fiber tissue or scar tissue. A lot of people come into the hospital and are having active symptoms, having heart attacks and you do the heart catheter and you see the artery is completely blocked. That is one of the very common conditions when you need a stent," said Dr. Acharya.