[Mitral valve prolapse and the ventricular pre-excitation syndrome (author's transl)]

One of the most important clinical aspects of the mitral valve prolapse syndrome is the high incidence of arrhythmias. Some recent reports on the association of mitral valve prolapse with ventricular pre-excitation may be relevant to the understanding of such arrhythmias. In order to evaluate the clinical relevance of this association, all patients with proven idiopathic mitral valve prolapse who came under our observation during the last twelve months, were submitted to careful electrocardiographic examination with the aim of detecting even subtle degrees of pre-excitation. His bundle recording and programmed atrial stimulation were performed if there was any suspicion of a delta wave. The association with ventricular pre-excitation was proved in 6 out of 41 examined cases. The main clinical, phonocardiographic, echocardiographic, angiographic and electrophysiologic data, as well as the familial study of these cases, are presented. The need for electrophysiologic study in some cases with doubtful electrocardiographic pattern is pointed out. While previous reports only described cases with left-sided accessory pathways, examples of right-sided pathways are presented in our series. The high incidence of mitral valve prolapse, and especially of pre-excitation syndrome and arrhythmias in the familial study, suggests that the association is not an occasional one. The detection of ventricular pre-excitation in cases of mitral valve prolapse complicated by recurrent tachy-arrhythmias may be of practical importance for an appropriate therapeutic approach.