Mitral Valve Prolapse
Posterior displacement or the anterior posterior or both mitral valve leaflets towards the left atrium
- Barlow syndrome
- Floppy valve syndrome
- Systolic click—murmur syndrome
- Redundant Cusp syndrome
- Billowing mitral valve syndrome
- Mid to late systolic
- Holosystolic (Pansystolic)
- Not yet clearly established
- Myxomatous degeneration of mitral valve: Middle layer (spongiosa component) of the leaflet, containing loose myxoid material, is unusually prominent. It is associated with mitral annular dilatation.
- There may be a hereditary component
- It has been associated with interatrial septal aneurysm, myocarditis, trauma, Ehlers-Danlos syndrome, SLE and WPW syndrome.
Signs and Symptoms
- Most patients asymptomatic
- Chest pain (usually atypical)
- Dyspnea, palpitations, arrhythmias, dizziness, syncope
- Progressive mitral regurgitation
- Infective endocarditis
- Embolic events (transient ischemic attacks, cerebrovascular accident)
- Ruptured chordae tendineae with acute mitral regurgitation
- Sudden death
- Normal (asthenic)
- Less of normal thoracic configuration (e.g., straight-back syndrome, scoliosis, pectus excavatum/ carinatum)
- Mid-late systolic click (due to sudden tensing of chordae tendineae) with or without systolic murmur (due to mitral regurgitation)
- Normal (in asymptomatic patients)
- Inverted/biphasic T waves
- Nonspecific ST-segment changes
- Thoracic abnormalities (e.g., scoliosis)
- None (reassurance)
- Endocarditis prophylaxis
- Beta blockers; antiarrhythmics
- Mitral valve repair/replacement if indicated
- Thick, redundant mitral valve leaflets. The thickness of the mitral valve leaflets can be determined by measuring the thickness of the anterior and/or posterior leaflets in mid-diastole. A thickness ≥ 5 mm is considered to be evidence of redundancy.
- Mid to late systolic “sagging” back of the anterior, posterior, or both mitral valve leaflets > 2 mm from the C-D points.
- Holosystolic (Pansystolic) sagging Back of the anterior posterior or both mitral valve leaflets ≥ 3 mm from the C-D points of the mitral valve.
- Abnormal late systolic dip in the left ventricular posterior wall
- Using the parasternal long-axis view as the gold standard, mitral valve prolapse is present when any portion of the anterior, posterior or both mitral valve leaflets prolapse beyond an imaginary line drawn from the origin of the posterior aortic root to the atrioventricular groove.
- Scalloped appearance of the involved mitt al valve leaflets in the parasternal short-axis view of the mitral valve.
- Left atrial enlargement due to significant mitral regurgitation
- Left ventricular enlargement due to significant mitral regurgitation
- Determine if tricuspid, aortic, or pulmonic valve prolapse is present.
- Mitral regurgitation (often predominantly late systolic)
Important to Note
- There is a wide spectrum of presumably normal valves and pro-lapsed valves. The differentiation between normal and prolapse is still unclear, making the diagnosis subjective at times.
- If the mitral valve appears redundant the patient is at a higher risk to suffer the complications of mitral prolapse (classic mitral valve prolapse).
- Mitral valve prolapse is very common among young women.
- Tricuspid valve prolapse is associated with mitral valve prolapse (up to 33%).
- Nearly all patients with Marfan’s syndrome have mitral valve prolapse.
- Provocative maneuvers such as the Valsalva maneuver or the administration of amyl nitrate (or any maneuver that reduces left ventricular volumes) may enhance mitral valve prolapse.
- Inferior angulation and/or high transducer position may cause false positives
- Mitral valve prolapse may be secondary to large pericardial effusion, primary pulmonary hypertension or atrial septal defect.
- The parameters for mitral valve prolapse as evaluated by trans-esophageal echocardiography have not yet been clearly established.