Following heart transplantation (HTx) in a 49-year old male, the patient's haemodynamic situation deteriorated in the early postoperative period despite increasing doses of catecholamines. When transoesophageal echocardiography (TEE) showed a dilated right ventricle, but adequate left ventricular (LV) function, a right ventricular assist device (RVAD) was implanted to support the right ventricle of the failing graft. Evaluation of the resulting cardiac output (CO) of the left ventricle and, thus, assessment of the remaining right ventricular function in patients supported by a RVAD is of great clinical interest. In this situation, continuous measurement of LV function, enabling assessment of the remaining right ventricular function, can be performed by pulse contour analysis following initial calibration of the system by arterial thermodilution CO measurement via a left atrial catheter.