[Complications of idiopathic mitral valve prolapse. Prevention and treatment].

Mitral valve prolapse is the most common form of heart disease, as it occurs in 4 to 6 per cent of the population. It has a benign course in the majority of cases, but 5 types of severe complication can occur in 15 per cent of cases. Mitral incompetence occurs in 14.8 per cent of cases. It may develop gradually or suddenly, following rupture of the chordae, which requires rapid surgical repair. Mitral valve prolapse is complicated by infectious endocarditis in 2.9 per cent of cases, hence the need for antibiotic prophylaxis prior to dental treatment or surgery in patients with a pan-systolic or end-systolic murmur. The only arrhythmias which should be considered as complications and treated as such are frequent ventricular extrasystoles of more than 30 per hour, usually associated with bigeminy, runs or polymorphism, ventricular tachycardia and ventricular fibrillation. Treatment consists, primarily, of beta-blockers. Sudden death is of course the major complication, occurring in 1.4 to 2.4 per cent of cases. The patients at risk of this complication are middle-aged women (40 years) with a past history of syncope or faintness due, in most cases, to episodes of ventricular tachycardia or ventricular fibrillation. Apart from arrhythmia, coronary artery spasm has also been found to be a cause of sudden death in these patients. Transient or definitive ocular and cerebral ischaemic episodes can also complicate mitral valve prolapse. Mitral valve prolapse is found in 20 to 30 per cent of patients with neurological accidents before the age of 45. Preventative treatment consists of anti-platelet aggregation agents and anticoagulants in recurrent cases.