04/07/2026
The mitral valve regulates blood flow from the left atrium to the left ventricle. When its function is impaired, characteristic murmurs occur.
1. Mitral Regurgitation (Insufficiency)
Occurs when the leaflets (anterior or posterior) do not close completely, causing blood to flow backward into the atrium.
Acoustic Symptom: Systolic murmur. It is typically prolonged (holosystolic) and has a "blowing" quality.
Auscultation Point: Best heard at the apex of the heart (5th intercostal space along the left midclavicular line).
Radiation: The murmur often radiates to the left axilla (armpit).
2. Mitral Stenosis
This is a narrowing of the valve or***ce due to leaflet fusion or annular fibrosis, making it difficult for the left ventricle to fill.
Acoustic Symptom: Mitral stenosis produces two diastolic murmurs, both of which are low-frequency. One occurs in mid-diastole, and the other occurs at the end of diastole with presystolic accentuation.
Additional Signs: An opening snap of the mitral valve and an accentuated S2 over the pulmonary artery (due to pulmonary hypertension).
Clinical Note: If the patient has Atrial Fibrillation (AFib), there is no active atrial contraction. Consequently, the diastolic murmur with presystolic accentuation will be absent.
3. Mitral Valve Prolapse (MVP)
Occurs when the leaflets (more commonly the posterior one) bulge into the atrial cavity during ventricular contraction.
Acoustic Symptom: A characteristic mid-systolic click (a short, sharp sound), which may be followed by a late systolic murmur.
💡 Why is this important for diagnosis?
The structures indicated in clinical diagrams (chordae tendineae and papillary muscles) play a key role. For example, a ruptured chordae tendineae leads to acute mitral regurgitation, which is often accompanied by a very loud, "musical" murmur.
📚 Sources:
Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine.
ESC/EACTS Guidelines for the management of valvular heart disease.
