Quantification and Prediction of Myocardial Failure

Introduction As the limits of surgical therapy have been extended to include more extensive procedures in the older age group, it has become increasingly more desirable for the surgeon to be able to gain a quantitative evaluation of the patient's myocardial capacity. Such evaluation should enable the detection of a borderline myocardial contractility prior to the onset of cardiac decompensation so that prophylactic measures may be instituted. The usual clinical characterization is not entirely satisfactory, since circulatory congestion is a nonspecific disturbance and may be present in instances where the heart does not fail as a muscle; and conversely, and more important, the heart may be a failing muscle and yet not demonstrate failure as a pump in the absence of stress.1,2 The present study was undertaken in an attempt to quantify the changes in the myocardial contractile state produced by the induction, by pentobarbital, of a reproducible and