A 23-year-old woman is diagnosed with mitral valve prolapse as seen on echocardiography for evaluation of a systolic murmur. Which of the following is most characteristic of mitral valve prolapse?

The most common pathogenic mechanism is thought to be excessive or redundant mitral leaflet tissue, with the posterior leaflet more commonly involved. Myxomatous degeneration can also be seen on pathologic examination. Reassurance regarding the benign nature of the disease is the mainstay of management. When a murmur is present, antibiotic prophylaxis for endocarditis is warranted.