The authors describe the case of a neonate with severe generalized hydrops. The cause was dextrolateral cardiac failure associated with early closure of the foetal ductus arteriosus. The author discusses general causes of foetal hydrops, its diagnosis and general treatment. He emphasizes the possible risk of premature closure of the ductus arteriosus in conjunction with administration of prostaglandin antagonists to pregnant women. The presented case demonstrates the high reactivity of the foetal and neonatal heart muscle to pressure and the ability of rapid anatomical reconstruction to normal even in case of severe hypertrophy of the cardiac musculature.

        Key words: ductus arteriosus, foetal hydrops, right-sided cardiac failure, hypertrophy of the neonatal heart muscle