Ischemic myocardial contracture ("stone heart"). A complication of cardiac surgery.

Stone heart or ischemic myocardial contracture is a complication of cardiopulmonary bypass characterized by contracture of the myocardium and inability to obtain cardiac output on manual massage. Stone heart has occurred only during aortic valve replacement and/or coronary artery bypass procedures. Predisposing factors are chronic congestive heart failure and myocardial hypertrophy with fibrosis secondary to longstanding aortic valve disease and/or coronary artery occlusive disease. Although the condition is rare, the outcome is usually fatal. Because of the biochemical and physiological implications of this syndrome, its prevention has been challenging. On the basis of our current concepts, prevention has been afforded by topical and general hypothermia and pretreatment with a small i.v. bolus of propranolol just prior to aortic occlusion. These measures have been utilized in potentially high-risk patients with the predisposition for stone heart and, thus far, the results have been satisfactory. The stone heart syndrome is an entity which should be recognized by all cardiac surgeons. Preventive measures must be aimed at protection of the myocardium during anoxic cardiac arrest.