Coronary Artery Disease (CAD), also known as Coronary Heart Disease (CHD), is a common heart condition caused by plaque buildup in the coronary arteries, which supply blood to the heart muscle. This plaque narrows the arteries, reducing blood flow and oxygen supply to the heart. CAD can lead to angina (chest pain), shortness of breath, and in severe cases, myocardial infarction (heart attack). Risk factors include high cholesterol, hypertension, diabetes, smoking, and a sedentary lifestyle.