Mitral valve prolapse full

• Prolapsing (billowing) mitral valve


  Also known as Barlow's syndrome or floppy mitral valve
• Prolapsing (billowing) mitral valve


  • Due to excessively large mitral valve leaflets
  • An enlarged mitral annulus
  • Abnormally long chordae
  • Disordered papillary muscle contraction
• Myxomatous degeneration


  Histological finding in prolapsing mitral valve
• Prolapsing (billowing) mitral valve is more commonly seen in young women than in men or older women
• Prolapsing (billowing) mitral valve has a familial incidence
• Prolapsing (billowing) mitral valve


  Associated with Marfan's syndrome, thyrotoxicosis, rheumatic or ischaemic heart disease
• Prolapsing (billowing) mitral valve


  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
• Mitral valve prolapse (MVP)


  Also variously termed the systolic click-murmur syndrome, Barlow's syndrome, floppy-valve syndrome, and billowing mitral leaflet syndrome
• MVP


  • A relatively common but highly variable clinical syndrome
  • Results from diverse pathogenic mechanisms of the mitral valve apparatus
• Excessive or redundant mitral leaflet tissue


  Commonly associated with myxomatous degeneration and greatly increased concentrations of acid mucopolysaccharide
• Cause of MVP

  • In most patients, unknown
  • In some, a genetically determined collagen disorder with a reduction in the production of type III collagen
• MVP

  A frequent finding in patients with heritable disorders of connective tissue, including Marfan syndrome, osteogenesis imperfecta, and Ehler-Danlos syndrome
• MVP


  • May be associated with thoracic skeletal deformities similar to but not as severe as those in Marfan syndrome, encompassing a high-arched palate and alterations of the chest and thoracic spine, including the so-called straight back syndrome
• MVP


  • In most patients, myxomatous degeneration is confined to the mitral (or, less commonly, the tricuspid or aortic) valves without other clinical or pathologic manifestations of disease
  • The posterior leaflet is usually more affected than the anterior, and the mitral valve annulus is often greatly dilated
  • Elongated, redundant, or ruptured chordae tendineae cause or contribute to the regurgitation
• MVP


  May occur rarely as a sequel to acute rheumatic fever, in ischemic heart disease, and in various cardiomyopathies, as well as in 20% of patients with ostium secundum atrial septal defect
• MVP


  • May lead to excessive stress on the papillary muscles, which in turn leads to dysfunction and ischemia of the papillary muscles and the subjacent ventricular myocardium
  • Rupture of chordae tendineae and progressive annular dilatation and calcification also contribute to valvular regurgitation, which then places more stress on the diseased mitral valve apparatus, thereby creating a vicious circle
  • The ECG changes and ventricular arrhythmias appear to result from regional ventricular dysfunction related to increased stress placed on the papillary muscles
• Mitral valve prolapse (MVP)


  • More common in females
  • Occurs most commonly between ages 15 and 30 years
  • Clinical course is often benign
  • May also be observed in older (>50 years) patients, often males, in whom MR is often more severe and requires surgical treatment
  • Increased familial incidence, suggesting an autosomal dominant form of inheritance
  • Encompasses a broad spectrum of severities, ranging from only a systolic click and murmur and mild prolapse of the posterior leaflet of the mitral valve to severe MR due to chordal rupture and massive prolapse of both leaflets
  • Condition may progress over years or decades, or worsen rapidly as a result of chordal rupture or endocarditis
• Asymptomatic


  Most patients are asymptomatic and remain so for their entire lives
• MVP is now the most common cause of isolated severe MR requiring surgical treatment in North America
• Arrhythmias associated with MVP

  • Ventricular premature contractions
  • Paroxysmal supraventricular tachycardia
  • Paroxysmal ventricular tachycardia
  • Atrial fibrillation
• Arrhythmias

  May cause palpitations, light-headedness, and syncope
• Sudden death


  • Very rare complication, occurs most often in patients with severe MR and depressed LV systolic function
  • May have an excess risk in patients with a flail leaflet
• Chest pain


  Often substernal, prolonged, and poorly related to exertion, and it rarely resembles angina pectoris
• Transient cerebral ischemic attacks


  May be secondary to emboli from the mitral valve due to endothelial disruption, though a causal relationship has not been established
• Infective endocarditis may occur in patients with MR and/or leaflet thickening
• Auscultation


  The most important finding is the mid- or late (non-ejection) systolic click, which occurs 0.14 s or more after the S1 and is thought to be generated by the sudden tensing of slack, elongated chordae tendineae or by the prolapsing mitral leaflet when it reaches its maximum excursion
• Systolic clicks


  • May be multiple and may be followed by a high-pitched, late systolic crescendo-decrescendo murmur, which occasionally is "whooping" or "honking" and is heard best at the apex
  • Occur earlier with standing, during the strain of the Valsalva maneuver, and with any intervention that decreases LV volume, exaggerating the propensity of mitral leaflet prolapse
  • Diminish with squatting and isometric exercises, which increase LV volume, diminish MVP, and the click-murmur complex is delayed, moves away from S1, and may even disappear
• Some patients have a mid-systolic click without the murmur; others have the murmur without a click. Still others have both sounds at different times
• ECG


  • Most commonly is normal but may show biphasic or inverted T waves in leads II, III, and aVF, and occasionally supraventricular or ventricular premature beats
• TTE


  • Particularly effective in identifying the abnormal position and prolapse of the mitral valve leaflets
  • A useful echocardiographic definition of MVP is systolic displacement (in the parasternal long axis view) of the mitral valve leaflets by at least 2 mm into the LA superior to the plane of the mitral annulus
• Color flow and continuous wave Doppler imaging


  • Helpful in revealing and evaluating associated MR
• TEE


  • Indicated when more accurate information is required and is performed routinely for intraoperative guidance for valve repair
• Invasive left ventriculography


  • Rarely necessary but can also show prolapse of the posterior and sometimes of both mitral valve leaflets
• Infective endocarditis prophylaxis


  Indicated only for patients with a prior history of endocarditis
• Beta blockers


  Sometimes relieve chest pain and control palpitations
• Mitral valve repair (or rarely, replacement)


  Indicated if the patient is symptomatic from severe MR
• Antiplatelet agents such as aspirin


  Should be given to patients with transient ischemic attacks
• Anticoagulants such as warfarin


  Should be considered if antiplatelet agents are not effective