Prosthetic valve thrombosis (PVT) is a rare but serious complication of valve replacement, most often encountered with mechanical prostheses. The different therapeutic modalities for PVT (fibrinolysis with heparin treatment or surgery) will largely be influenced by the presence of valvular obstruction, the valve location (left or right sided), the patient's clinical status, the existence of and expertise in therapeutic modalities at the institution, and the patient's decision. This report describes a patient with thrombosis of a prosthetic mitral valve, which was successfully treated with recombinant streptokinase in a hospital without cardiac surgery. In this context, the authors present the real-time transoesophageal echocardiographic appearance of this complication, and give a brief review of the literature.