Ultrasonic evaluation of thrombosis of Björk-Shiley aortic valve prosthesis.

Recognition of thrombosis of a Björk-Shiley aortic valve prosthesis 4 years after insertion in a patient was based upon sudden clinical deterioration, loss of prosthetic sounds, and development of new stenotic and regurgitant murmurs. Thrombotic fixation was confirmed by diagnostic alterations on the echocardiogram. All manifestations reverted to normal after successful surgical debridement of the prosthesis. Echocardiography is a valuable noninvasive adjunct in the differential diagnosis of prosthetic valve malfunction.