[Fetal arrhythmia].

Our present knowledge of fetal arrhythmias is described with reference to the literature and to the authors' personal experience. Most types of arrhythmia are harmless. Fetal tachyarrhythmias are of clinical importance, because of the danger of fetal cardiac insufficiency, and atrioventricular blocks because they are closely associated with infantile heart defects and maternal collagen disease. Problems of diagnosis and management are discussed.