Intermittent electromechanical dissociation due to mechanical prosthetic valve dysfunction.

We describe a patient who developed the rare hemodynamic phenomenon of intermittent electromechanical dissociation during normal sinus rhythm at about four months after mitral valve replacement with a Medtronic Hall prosthesis, along with resuspension of the papillary muscles using Gore-Tex sutures. Echocardiographic examination confirmed the presence of a filamentous structure that could be either suture material, tissue tag or thrombus, and was entangling intermittently in the prosthesis. The patient recovered spontaneously after a three-week symptomatic period, with no subsequent evidence of either electromechanical dissociation or the filamentous structure; normal prosthetic valve function was restored. During a subsequent three-month follow up period, the patient was asymptomatic, with normal prosthetic valve function. The diagnostic and hemodynamic aspects of this case are discussed.