This disease affects the coronary arteries, which supply blood flow to the heart. Fatty substances, cholesterol, calcium and other substances build up along the walls of the coronary artery forming plaque (atherosclerosis). Overtime, this plaque buildup causes the arteries to harden and become narrowed, reducing blood flow to the heart. Eventually plaque can completely block the arteries.

 
Blood clots can form on the plaques rough surface. Plaque can also rupture, causing a blood clot to form. Both of these conditions can completely obstruct the artery, resulting in a heart attack or stroke.

Coronary artery disease develops slowly, over years. Risk factors for developing coronary artery disease include high blood cholesterol, high blood pressure, obesity, smoking, diabetes, family history of heart disease and physical inactivity.

There are often no symptoms of coronary artery disease until the blood flow has become severely reduced. Typical symptoms include chest pain (angina), shortness of breath, dizziness or lightheadedness. Sometimes, the first sign of coronary artery disease is a heart attack.

Coronary artery disease can be diagnosed through a variety of tests, including an electrocardiogram, exercise stress test, echocardiogram, nuclear scan and coronary angiography.

Treatment for coronary artery disease depends on the severity of the disease. Mild cases can be treated with medication and lifestyle changes, such as quitting smoking, losing weight, regular exercise and a heart-healthy diet. Medications include cholesterol-lowering medications, aspirin, Beta-blockers, calcium channel blockers and blood pressure lowering drugs. For more advanced cases of coronary artery disease, treatment may include balloon angioplasty with stent placement, or coronary artery bypass surgery.