Papillary muscle dysfunction

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Overview
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Pathophysiology & Etiology
Left ventricular papillary muscles are perfused by the terminal portion of the coronary vascular bed, therefore, they are particularly vulnerable to ischemia, and any disturbance in coronary perfusion may result in papillary muscle dysfunction.

The posterior papillary muscle (supplied by the posterior descending branch of the right coronary artery) more frequently becomes ischemic and infarcted than the anterolateral papillary muscle (supplied by diagonal branches of the left anterior descending coronary artery and/or by the left circumflex artery).

Burch classification
Burch et al first proposed that papillary muscle dysfunction could be due to either mitral valve prolapse or incomplete mitral valve closure


 * Papillary muscle ischemia.
 * Left ventricular dilatation.
 * Non ischemic papillary muscle atrophy.
 * Congenital abnormalities of papillary muscles or tendons.
 * Endocardial diseases (endocarditis, fibroelastosis).
 * Expansion or hypertrophic cardiomyopathy.
 * Papillary muscle contraction coordination abnormalities.
 * Papillary muscle or tendon rupture.

History and Symptoms
Palpitations, shortness of breath and cough.

Electrocardiogram
Left atrial enlargement or non specific ST segment and T wave changes may occur.

Chest X Ray
Left atrial enlargement may be present

Echocardiography and Doppler Ultrasound

 * Two dimensional electrocardiograph may show changes in thickness of papillary muscle, an increase in leaflet flexibility, ventricular dilatation and tendon rupture if there is any.


 * Doppler US may detect mitral regurgitating flow