[Changes in the immune response in postoperative patients while running the ventricular assist device (VAD)]

We examined the immunological parameters in two patients who were assisted with LVAD in postoperative LOS. Both patients demonstrated transient consumption of complements immediately after running the LVAD. The serum concentrations of immunoglobulins (IgG, IgM, IgA) showed no significant decrease. Both patients had significant postoperative lymphopenia, but recovered in a week. A decrease in the number of T cells was observed in both patients. The OKT4/OKT8 ratio initially increased in one patient, but gradually declined postoperatively. In the other patient, the OKT4/OKT8 ratio decreased. The lymphocyte response to mitogen (PHA) remained significantly depressed when the number of lymphocytes returned to the normal level, suggesting that the lymphocytes were functionally impaired. Such findings are generally observed after cardiac surgery. Thus, LVAD does not affect the immune response.