VALVULAR REOPERATIONS. RISK ANALYSIS FOR HOSPITAL MORBIDITY AND MORTALITY

Abstract
Were analysed prospectively 194 patients that underwent valvar reoperations between July 1995 and June 1999 in the Heart Institute FMUSP. The following variables were studied: sex, age, functional class (FC), number and type of previous operations, cardiac rhythm, urgency at operation, creatinin level, left ventricular ejection fraction (LVEF), left ventricular systolic and diastolic diameters, right ventricular systolic pressure, prothrombin activity, activated partial thromboplastin time relation, platelets count, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, number and position of valves, type of procedure, associated procedures and intraoperative bleeding volume. Multivariate statistical analysis by logistic regression was performed to determine risk factors for hospital mortality and morbidity (cardiovascular, respiratory, renal). The overall hospital mortality was 8,8%. Multivariate analysis identified FC, creatinine, and CPB time as independent predictors of hospital mortality. FC, creatinine, LVEF and sex were predictive of cardiovascular morbidity. FC, creatinine and CPB time were predictive of respiratory morbidity. FC and creatinine were preditive of renal morbidity. The variables FC IV and seric creatinin > 1.5 mg/dl were independent predictors of hospital mortality and morbidity in valvar reoperations.

Key words
heart valves, surgery, risk factors, reoperation, functional class

Bibliografía del artículo

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