Posterior midventricular rupture after mitral valve replacement.

Posterior midventricular rupture occurred in 3 patients after insertion of a mitral prosthesis. Iatrogenic surgical trauma was not implicated. There were five clinical factors common to each case: a woman with mitral stenosis; a left ventricle of relatively normal size; the use of intermitent cold cardioplegia; the insertion of a porcine heterograft valve; and transient postoperative hypertension. Rupture in such cases may be caused by hyperdynamic left ventricular contraction against the strut of the prosthesis. Causes of ventricular perforation are discussed.