coronary heart disease

coronary heart disease, disease characterized by an inadequate supply of oxygen-rich blood to the heart muscle (myocardium) because of narrowing or blocking of a coronary artery by fatty plaques (see atherosclerosis). If the oxygen depletion is extreme, the effect may be cardiac arrest or a myocardial infarction (heart attack). If the deprivation is insufficient to cause infarction (death of a section of heart muscle), the effect may be angina pectoris (pain or discomfort in the chest). Both conditions can be fatal because they can lead to heart failure or ventricular fibrillation. The latter, characterized by an uncontrolled and uncoordinated contraction of the ventricles (the lower chambers of the heart), can induce sudden death.

A variety of risk factors have been associated with coronary heart disease; examples include high blood pressure, elevated blood cholesterol levels, smoking, obesity, diabetes, unhealthy diet, and family history of early coronary heart disease (i.e., diagnosed in middle age). Individuals with hereditary conditions such as familial hypercholesterolemia (a disorder in which the body’s tissues are incapable of removing cholesterol from the bloodstream) also are at increased risk.

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Diseases, Disorders, and More: A Medical Quiz

Coronary artery bypass surgery (also known as coronary artery bypass grafting) or angioplasty may be necessary if medications and diet and lifestyle changes, such as frequent exercise and cessation of smoking, are not effective.