They have the murmur of mitral regurgitation but the leak is usually not severe enough to be of hemodynamic importance. Also functional mitral stenosis may occur. But again, usually not severe. These patients may have conduction abnormalities, bundle branch blocks and AV block as a consequence of progression of calcification from the annulus of the heart into the conduction system of the heart. These patients are in fact at risk of systemic embolization even without atrial fibrillation.
Mitral prolapse encompasses a very wide spectrum of disease.
It has in the past been considered almost to be a normal variant. This depends on how one defines mitral valve prolapse. One can define mitral valve prolapse at a way in which we grade the diagnostic criteria from trivial to mild, to moderate, to severe. And the differentiation of trivial prolapse from no prolapse is really a fine distinction best made by an expert echocardiographer. It is a common entity, particularly if one includes the patients with trivial prolapse.