[Ventricular arrhythmias and mitral valve prolapse. A study of 35 cases]

35 patients with mitral valve prolapse (MVP) underwent investigation by Holter monitoring with computerised analysis. Ventricular arrhythmias were observed in 70% patients with MVP. There does not seem to be a close correlation between the severity of the arrhythmia and the degree of prolapse. The mechanisms of the ventricular arrhythmia are variable: two patients had the necessary criteria for ventricular reentry, at least six had parasystolic foci, protected or not from the sinus rhythm. The most severe ventricular arrhythmias are characterised by their variable morphology (but usually showing right bundle branch block), a clear diurnal rhythm, the inducing role of exercise or emotion and a greater diurnal variation of the sinus rhythm suggesting increased sympathetic tone. The results of beta blockade are better in the patients with the most marked diurnal rhythms.