Clincal Case of Intermittent chest pain and palpitation

A 30 year old female presented with complaints of progressive breathlessness since 6 months. There was history of intermittent chest pain and palpitation. On examination her HR was 88/min and BP was 140/80 mm of Hg and a late systolic murmur with midsystolic click at cardiac apex. Pathological examination of the heart is most likely to show which of the following in this patient? 

A. Fatty replacement of the ventricle with thinning of the RV free wall 

B. Hooding of the mitral valve leaflets with myxomatous degeneration 
C. Ischemia of the papillary muscles 
D. Elongated and ruptured chordae tendineae

Ans. B. Hoodingof the mitral valve leaflets with myxomatous degeneration.

Myxomatous degeneration of the mitral valve with hooding and prolapse of the posterior mitral leaflet into the left atrium is characteristic of mitral valve prolapse.

Prolapsing ,billowing.  mitral valve:-

This is also known as Barlow's syndrome or floppy mitral valve. It is due to excessively large mitral valve leaflets, an enlarged mitral annulus, abnormally long chordae or disordered papillary muscle contraction. Histology may demonstrate myxomatousdegeneration of the mitral valve leaflets. It is more commonly seen in young women than inmen or older women and it has a familial incidence.  Its cause is unknown but it is associated with Marfan'ssyndrome, thyrotoxicosis, rheumatic or ischaemic heart disease. It also occurs in association with atrial septal defect and as part of hypertrophic cardiomyopathy. Mild mitral valve prolapse is so common that it should be regarded as a normal variant.

Pathophysiology - During ventricular systole, a mitral valve leaflet most commonly the posterior leaflet.  prolapses into the left atrium. This may result in abnormal ventricular contraction, papillary muscle strain and some mitral regurgitation. Usually.the syndrome is not haemodynamically serious. Thromboembolism occurs. 

Symptoms:  Atypical chest pain is the most common symptom. Usually the pain is left submammary and stabbing in quality. - Sometimes it is substernal, aching and severe. Rarely it is similar to typical angina pectoris. Palpitations may be experienced because of the abnormal ventricular contraction or because of the atrial and ventricular arrhythmias that are commonly associated with mitral valve prolapse.  Sudden cardiac death due to fatal ventricular arrhythmias is a very rare but recognized complication.

Signs  The most common sign is a mid-systolic click, which is produced by the sudden prolapse of the valve and the tensing of the chordae tendineae that occurs during systole. This may be followed by a late systolic murmur owing to some regurgitation. With more regurgitation, the murmur becomes pansystolic mitral regurgitation.