Complete atrioventricular block is a chief complication of operation on heart. Between 1990 and 2001, 5662 open cardiac procedure for congenital heart defects were performed at Children Hospital Los Angeles. 72 patients with persistent postoperative complete heart block underwent pacemaker implantation. After insertion of the pacemaker, recovery of atrioventricular conduction was recognized in 7 of 72 patients at a median 41 days (18-113days) after the initial cardiac operation. But for many Chinese patients, the pacemaker is too expensive to afford. Cardiac muscle cells can quickly set up electrical coupling after primary culture. We all know the connecting between atrial muscle cell and sinoatrial node cell. If sinoatrial node cells can set up electrical coupling with ventricular muscle cells after sinoatrial node autotransplantation, and they could lead the ventricular muscle, more patients of complete heart block could afford.Aim: To observe can the sinoatrial node cells set up electrical coupling with ventricular muscle cells after sinoatrial node autotransplantation, To observe the change of sinoatrial node cell culturing with myocardial cell.