Valvular insufficiency

Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. It is the circulatory equivalent of backflow in engineered systems. It is sometimes called reflux, as in abdominojugular reflux. Regurgitation is blood flow in the opposite direction from normal, as the backward flowing of blood into the heart or between heart chambers. It is the circulatory equivalent of backflow in engineered systems. It is sometimes called reflux, as in abdominojugular reflux. Regurgitation in or near the heart is often caused by valvular insufficiency (insufficient function, with incomplete closure, of the heart valves); for example, aortic valve insufficiency causes regurgitation through that valve, called aortic regurgitation, and the terms aortic insufficiency and aortic regurgitation are so closely linked as usually to be treated as metonymically interchangeable.