Intermittent electromechanical dissociation as an unusual sign of prosthetic valve thrombosis in a patient with prosthetic fibrous ingrowth

We describe the echocardiographle features of an unusual hemodynamic phenom enon of intermittent electromechanical dissociation during regular sinus ta chycardia in a patient with prosthetic mitral valve thrombosis. Thrombolysi s with a solution of recombinant tissue-type plasminogen activator resulted In the disappearance of electromechanical dissociation and was effective i n stabilizing the patient's condition. The later discovery of panus coverin g the valve ring after the lysis of clots confirmed surgery as the definiti ve treatment.