A previous study from this Department demonstrated a reversible depression of radionuclide-determined ejection fraction in survivors of septic shock. In order to further characterize the myocardial response to septic shock and, in particular, the difference in left ventricular function between survivors and non-survivors of septic shock, serial radionuclide angiography with simultaneous hemodynamic measurements are performed. The studies are done on the first day of septic shock, on day 3 or 4, and a week to 10 days after the onset of shock to try to determine the patterns of response in the two groups. Survivors of septic shock show a decrease in ejection fraction accompanied by dilation of the left ventricle over the first 3-4 days of septic shock. These changes return toward normal a week to 10 days later as the patients recover. Non-survivors develop patterns seen on serial studies. Half of the non-survivors develop left ventricular dilatation and maintain their stroke volume and cardiac output. The other half of the non-survivors have a decreasing left ventricular end diastolic volume associated with a falling stroke volume and cardiac index. Failure to develop left ventricular dilatation may represent an inability of the ventricle to compensate for myocardial depression and contribute to the demise of this subgroup of non-survivors.
