Pressure damping, a "billowing" septum, and an eerie silence: perioperative, intermittent obstruction of a mitral valve prosthesis.

This case, involving a 74 year old man who underwent mitral valve and aortic valve replacements, provides detailed insight into the perioperative echocardiographic and haemodynamic changes occurring when a mitral valve prosthesis intermittently obstructs. It illustrates the early sequence of electromechanical dissociation which would lead to cardiac arrest should a tilting disc prosthesis be immobilised in the closed position.