[Risk of reoperations and acute interventions in valvular surgery]

Reoperations in valvular surgery can be subdivided into procedures following reconstructive measures (group A) and interventions following implantation of a valve prosthesis (group B). In group A (valve replacement after conservative mitral surgery, 41 cases from 1976 to 1984 in our institution), operative mortality does not significantly differ from patients undergoing primary isolated mitral valve replacement (7.3% v. 4.4%). In group B, however, the risk of prosthetic valve reoperation mainly depends on the morphological alterations implying the surgical intervention. Among these conditions, prosthetic valve endocarditis has the poorest prognosis (operative mortality 25% in our own experience), especially if an emergency intervention is mandatory as a result of severe heart failure. In contrast to this high risk group, patients being reoperated on an elective basis due to paraprosthetic leakage or recurrent arterial embolism, do not show a higher risk when compared to first procedures. The risk of emergency surgery on native heart valves is discussed under the consideration of patients suffering from acute infective endocarditis (AIE). As in reoperations, the preoperative cardiac functional status and the urgency of the surgical intervention are the principal determinants for the operative risk. Both for reoperations and emergency procedures surgical timing is of great importance in the management of valvular patients; when ever possible, surgery should be carried out before the development of advanced ventricular failure necessitates an intervention under emergency conditions.