Mitral Stenosis I: Introduction

Mitral stenosis is a medical condition where the mitral valve becomes narrow, restricting blood flow from the left atrium to the left ventricle, most commonly caused by rheumatic endocarditis.

Less common causes include congenital malformations, autoimmune disorders, radiation therapy, and severe mitral annular calcification.

The pathophysiology involves rheumatic endocarditis, which causes inflammation and scarring.

This leads to thickening, calcification, and fusion of the mitral valve leaflets and chordae tendineae, narrowing the valve orifice and obstructing blood circulation from the left atrium to the left ventricle during diastole.

As a result, residual blood volume in the left atrium increases, causing left atrial hypertrophy and dilation over time.

Continued high pressure in the left atrium can cause pulmonary congestion and edema and make the atrium prone to arrhythmias like atrial fibrillation, which decreases cardiac efficiency.

It may also cause pulmonary hypertension and strain on the right ventricle, potentially leading to right ventricular hypertrophy and heart failure.