Explained: What Is Coronary Artery Disease? Know Its Causes, Symptoms And Treatment

Coronary artery disease is a disease which affects the larger coronary arteries on the surface of the heart, as a result of which the arteries cannot deliver enough oxygen-rich blood to the heart. 

An illustration depicting blockage in a large heart artery, leading to coronary heart disease or ischemic heart disease.

Source : Getty

Coronary artery disease, also known as ischemic heart disease or coronary heart disease, affects more than 10 million people in India and around 126 million individuals worldwide per year. This is a type of heart disease which affects the larger coronary arteries on the surface of the heart, as a result of which the arteries cannot deliver enough oxygen-rich blood to the heart. 

Coronary artery disease is different from coronary microvascular disease, which affects the tiny arteries in the heart muscle, and is more common in women, according to the United States National Institutes of Health (NIH). 

Coronary artery disease is the most common type of heart disease and a leading cause of death worldwide.

According to a recent study published in The Lancet, a computer-derived marker for coronary artery disease, developed by researchers at the Icahn School of Medicine at Mount Sinai in New York, can be used to better measure clinically important characteristics of the disease. 

Causes of coronary artery disease

Coronary artery disease can occur due to different reasons such as cholesterol building up inside the lining of coronary arteries and forming plaque, resulting in a partial or total block of blood flow in the large arteries of the heart. A heart-healthy lifestyle can help prevent coronary artery disease.

People might have the same type of coronary artery disease, yet, the symptoms could differ. 

The process of plaque buildup causing the inside of the arteries to narrow over time is called atherosclerosis. 

Sometimes, people suffering from coronary artery disease might have no symptoms. However, there are chances that blood flow to their heart is blocked abruptly, resulting in a heart attack, or chest pain. Coronary artery disease can cause the heart to suddenly stop working, a heart problem called cardiac arrest.

Symptoms of coronary artery disease

The most common symptom of coronary artery disease is angina, or chest pain and discomfort, which can happen when too much plaque builds up inside the arteries, causing them to narrow, according to the Centers for Disease Control and Prevention (CDC). Narrowed arteries can block blood flow to the heart muscle and the rest of the body, leading to chest pain. 

People with no symptoms realise that they have coronary artery disease when they have a heart attack. The symptoms of heart attack include angina, pain or discomfort in the arms or shoulder, weakness, light-headedness, nausea, and shortness of breath. 

Coronary artery disease can weaken the heart muscle over time, leading to heart failure, a serious condition where the heart cannot pump blood the way it should. 

Risk factors for coronary artery disease

The risk factors for coronary artery disease include being overweight, physically inactive, eating unhealthy food, and smoking tobacco. People with a family history of heart disease have a higher risk of coronary artery disease.

How can coronary artery disease be diagnosed?

There are several ways to diagnose coronary artery disease. These include using an electrocardiogram, a test which measures the rate, regularity and electrical activity of one's heartbeat, echocardiogram, which uses ultrasound to create a picture of the heart, exercise stress test, which measures the heart rate while one is walking on a treadmill, and helps to determine how well the heart is working when it has to pump more blood, a chest X-ray, which creates a picture of the heart, lungs and other organs in the chest, coronary angiogram, which monitors blockage and flow of blood through the coronary arteries, and uses X-rays to detect dye injected through cardiac catheterisation, which checks the inside of one's arteries for blockage by inserting a thin, flexible tube through an artery in the groin, neck or arm to reach the heart, and coronary artery calcium scan, which is a computed tomography scan that looks in the coronary arteries for calcium buildup and plaque.

How can coronary artery disease be treated?

The treatment for coronary artery disease depends on how serious one's symptoms are and the health conditions they have. For instance, if one is experiencing a heart attack, they may need emergency treatment. People with coronary artery disease should also make heart-healthy lifestyle changes. 

Some heart-healthy lifestyle changes include aiming for a healthy weight, eating heart-healthy foods such as fruits, vegetables, and whole grains, and limiting saturated fats, sodium and added sugars, being physically active, managing stress, quitting smoking, and getting enough good-quality sleep. 

Medicines which can reduce or prevent chest pain and other symptoms associated with coronary artery disease include ACE inhibitors and beta blockers, which help lower blood pressure and decrease how hard one's heart is working, medicines such as empagliflozin, liraglutide and canagliflozin, which  control blood sugar and help lower the risk for complications if one has ischemic heart disease, ranolazine, statins or non-statin therapies, which control high blood cholesterol, calcium channel blockers to lower blood pressure by allowing blood vessels to relax, non-statin drugs such as sequestrants, evolocumab and alirocumab to reduce cholesterol when statins do not lower cholesterol enough, nitrates such as nitroglycerin to dilate the coronary arteries and prevent chest pain, and metformin to control plaque buildup if one has diabetes. 

If one's coronary artery disease causes serious complications, they might need to undergo heart surgery or procedure.