Mitral stenosis overview


 * Associate Editor-In-Chief: Mohammed A. Sbeih, M.D. [mailto:msbeih@perfuse.org]

Overview
Mitral stenosis is a valvular heart disease characterized by narrowing of the orifice of the mitral valve of the heart.

In normal cardiac physiology, the mitral valve opens during left ventricular diastole, to allow blood to flow from the left atrium to the left ventricle. Blood flows in the proper direction because during this phase of the cardiac cycle; the pressure in the left ventricle is lower than the pressure in the left atrium, and the blood flows down the pressure gradient.

In the case of mitral stenosis, the valve does not open completely, and to transport the same amount of blood ,the left atrium needs a higher pressure than normal to overcome the increased gradient.

Mitral stenosis typically progresses slowly (over decades) from the initial signs of mitral stenosis to NYHA functional class II symptoms to the development of atrial fibrillation to the development of NYHA functional class III or IV symptoms. Once an individual develops NYHA class III or IV symptoms, the progression of the disease accelerates and the patient's condition deteriorates.

Severe mitral stenosis (MS) is eventually lethal disease unless treated with vulvotomy or valve replacement, it may progress to serious complications like pulmonary hypertension, heart failure and death. Most of the cases are due to rheumatic heart disease.