[The heart in myasthenia gravis. Electrocardiographic, cardiodynamic and kinetocardiographic aspects in 18 cases].

Eighteen patients with myasthenia gravis, second-stage (A or B) according to Ossermann and Genkins, and of young age, were examined as outpatients from the cardiological point of view. Clinical and radiological examination of the heart and large vessels revealed no pathological features. Electrocardiographic abnormalities (including one case of ventricular preexcitation syndrome and one of subepicardial ischemia) were detected in three patients (16,6%). Among the various left ventricular systolic time intervals, only the deformation time was somewhat off normal limits in some cases, but the difference was not statistically significant. In over one-third of the cases, conversely, the kinetocardiogram revealed paradoxical systolic outward movements, indicative of myocardial dyskinesis or dissinergy. The essential normality of systolic time intervals in the presence of manifest abnormalities of the kinetocardiographic curve may be explained by the smallness of hypokinetic or dyskinetic areas, whereby the ejection fraction was not reduced. In general, the ECG and kinetocardiographic tracings showed no tendency to change under the effect of orally administered pyridostigmine.