Of a total of 133 patients who underwent heart transplantation, 16(12%) had pericardial and mediastinal complications. Non-infectious pericardial complications, pericardial effusion and constriction were noted in ten patients, and infectious pericarditis or mediastinitis in six. Cardiac echocardiography, catheterization and magnetic resonance imaging were useful in assessing these problems. All patients underwent surgical treatment, pericardial drainage, pericardectomy or muscle flap closure. Twelve (75%) of these 16 patients are long-term survivors. In conclusion, pericardial and mediastinal complications are common after heart transplantation, and aggressive surgical treatment is most often effective in their control.