We report a patient who presented with paraprosthetic leak complicated by d
issection of the interatrial septum after mitral valve replacement. A revie
w of the literature provides confirmation that only 3 cases have been previ
ously reported of this potential, albeit extremely rare, complication of pr
osthetic mitral valve replacement. Prosthesis oversizing and improper mitra
l annular handling appeared to be the predisposing factors of this complica
tion. (Ann Thorac Surg 2001;71:1670-2) (C) 2001 by The Society of Thoracic
Surgeons.