A clinical case of cryoballon ablation of pulmonary veins in a patient with atrial fibrillation with congenital heart disease: persistent left superior vena cava, atresia of the superior vena cava. The methods of investigation at the preoperative stage are described, which allow to plan the operation in advance, taking into account the peculiarities of the confluence of the main veins into the heart, and also some technical features of cryoballon ablation surgery are emphasized.