TY - CHAP M1 - Book, Section TI - DEGENERATIVE MITRAL VALVE DISEASE A1 - Castillo, Javier G. A1 - Adams, David H. A1 - Carabello, Blase A. A1 - Sengupta, Partho P. A2 - Fuster, Valentin A2 - Harrington, Robert A. A2 - Narula, Jagat A2 - Eapen, Zubin J. PY - 2017 T2 - Hurst's The Heart, 14e AB - The normal mitral valve permits one-way blood flow from the left atrium to the left ventricle in an efficient, nearly frictionless fashion.1 Although even a normal competent valve may allow a trivial amount of reversed flow, more than a trace of mitral regurgitation is considered pathologic.2 Mild-to-moderate mitral regurgitation is tolerated indefinitely as long as it does not worsen. However, severe mitral regurgitation causes left ventricular remodeling reduced forward cardiac output, neurohumoral activation, left ventricular damage, heart failure, and ultimately death.3 The natural history of mitral regurgitation depends intimately on its etiology, the severity of left ventricular volume overload as well as its contractile performance, and the appearance of overlapping clinical conditions secondary to reversal flow, such as atrial fibrillation and pulmonary hypertension.4 In this setting, myxomatous degeneration of the mitral valve, a very common pathologic substrate of mitral valve billowing (normal valve coaptation) and prolapse (deficient valve coaptation), is the most prevalent cause of isolated severe mitral regurgitation requiring surgical intervention in the United States.5 The following is a review of the normal mitral valve anatomy as well as a summary of causes, consequences, and treatment of degenerative mitral valve regurgitation. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - accessmedicine.mhmedical.com/content.aspx?aid=1161731456 ER -