Mitral valve prolapse
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(Barlow's disease)
Present in about 1 to 3 % of the population.
Systolic ballooning of the mitral valve due to an excess or redundancy of mitral tissue. The posterior leaflet is in general more affected than the anterior, and the mitral ring is dilated. More frequent in females. Sometimes associated with Marfan syndrome or Ehlers-Danlos syndrome, pectus excavatum, idiopathic scoliosis, osteogenesis imperfecta. The severity is variable: from a single systolic click with or without a mitral murmur to severe regurgitation. Often asymptomatic but can cause rhythm disorders (often ventricular), palpitations, syncope.
It causes serious heart problems only if regurgitation becomes severe, in case of infection of the valve (endocarditis) or rupture of the weakened tissue.
Diagnosis: mesosystolic click at the mitral focus.
Two-dimensional echocardiography: systolic hernia or protrusion of more than 2 mm of one or both sheets of the mitral valve in the left atrium on a longitudinal parasternal long axis section.
The prolapse can be associated with mitral disjunction: the mitral ring is partially detached from the ventricular myocardium, allowing hypermobility of the mitral valve. It is diagnosed echocardiographically when image-by-image analysis of the posterolateral ring in large axis parasternal transthoracic view reveals a systolic separation of the ring and ventricular myocardium of a few millimeters up to one centimeter.
A distinction is made between the classic form if the thickness of the mitral sheets is > 5 mm and the non-classic form if it is < 5 mm.
Anesthetic implications:
avoid causes of decreased left ventricular volume as this increases the mitral regurgitation and carries a risk of rhythm disorders: hypovolemia, tachycardia. Risk of ventricular fibrillation. Endocarditis prophylaxis.
References :
- Moritz HA, Parnass SM, Mitchell JS.
Ventricular fibrillation during anesthetic induction in a child with undiagnosed mitral valve prolapse.
Anesth Analg 1997; 85: 59-61.
Updated: September 2022