[Mitral valve prolapse and spasmophilia in the adult].

75 cases of mitral valve prolapse (MVP) for which no cause was found underwent electromyography (EMG). In 64 cases (85.3%) EMG showed changes suggestive of spasmophilia. The symptoms observed were those already described in this condition. The specific clinical signs of spasmophilia were often elicited with a positive Chvostek sign in 20 out of 30 cases (73.3%). Radiological, echocardiographical and haemodynamic studies underlined the hyperkinetic state of the left ventricle. Biochemical investigations showed a high incidence of low erythrocytic magnesium levels. Chest pain suggestive of angina pectoris, mitral valve prolapse and spasmophilia are frequently associated. The role of the low erythrocyte magnesium on left ventricular hyperkinesis and the production of MVP is discussed.