Successful thrombolysis of a partially obstructed bileaflet prosthetic heart valve in the mitral position.

We describe the case of a woman who presented with dyspnea of abrupt onset and who had recently undergone replacement of the mitral valve with a bileaflet mechanical prosthesis. Transthoracic echocardiographic examination with spectral Doppler recording of transvalvular blood flow revealed a velocity spectrum consistent with obstruction. Transesophageal echocardiography demonstrated partial obstruction of the prosthetic valve due to immobilization of 1 hemidisc in the closed position. This immobilization was apparently caused by a small mass whose appearance was consistent with that of a thrombus. The patient was successfully treated by intravenous administration of a thrombolytic agent. This case demonstrates the value of transesophageal echocardiography in the selection of candidates for thrombolytic treatment in cases of thrombosis of a left-sided valve prosthesis.