FIELD: medicine. SUBSTANCE: method involves forming intra-atrial cava-to-cava tunnel using fastening suture produced with an apparatus. Apparatus branch is introduced into interatrial septum defect. The upper branch is positioned on the external wall of the right auricle. Apparatus branches are arranged in the direction of horizontal boundary crest part. Fastening sutures are put in. Apparatus cartridge is changed. The lower branch is introduced into the interatrial defect in the direction of medial Eustachian valve and fastening sutures are put in. Discharge fistula being required, the medial and lateral edges of the right atrium wall incision are sewn together. No discharge fistula being required, the right atrium wall incision suturing is carried out with lateral interatrial defect edge being captured. EFFECT: enhanced effectiveness of treatment; shorter intraoperative ischemia period; lower degree of tissue injuries. 5 dwg
