Objective To evaluate intra-myocardial electrocardiography(IMEG) for rejection monitoring in transplanted heart.Methods The electrode was anchored in the transplanted right ventricular wall during operation in all patients,and the electrode was connected to the permanent pacemaker to monitor the change of QRS wave in IMEG after the operation.Results The average of R wave amplitude was not decreased after operation in 4 patients who were alive with good quality of life.1 patient died of acute renal failure 8 days after operation.Conclusion IMEG can be used for long time monitoring the rejection after non invasive heart transplantation and reduce the need of endomyocardial biopsy(EMB).