Forty patients with tumors of the esophagus, cardia and rectum, subjected preoperatively to gamma-therapy (500 rad for 6 days) and 24 patients subjected only to the operation (the control group) were examined for the heart rate, arterial pressure, minute and stroke heart volumes and circulatory volume (AFS--J131) before and after irradiation and 1, 3, 5 days following the operation. Gamma-therapy was found to result in more poor hemodynamic indices whether the heart is irradiated or not. In irradiation of the heart region (cancer of the esophagus and cardia) much poorer hemodynamic indices were noted.