Left ventricular assist system support is associated with persistent inflammation and temporary immunosuppression

Background: In patients undergoing left-ventricular assist system support, it has not been elucidated to which extent mechanical circulatory support itself as opposed to the underlying condition of endstage heart-failure contributes to perturbation of immune homeostasis. Methods: In eleven heart transplant candidates who had to undergo Novacor left-ventricular assist device bridging, we prospectively sampled interleukin-6, T-cell and monocyte subsets and compared them to fifteen UNOS status II patients awaiting cardiac transplantation on medical heart failure treatment as outpatiens at the time of LVAS implantation/listing decision as well as 2.0 +/- 1.2 months and 4.5 +/- 2.3 months later. In order to assess deviations in both groups from normal values, thirty-two healthy subjects served as reference group. Results: Patients undergoing Novacor bridging had higher C-reactive protein, leukocyte, neutrophil, and monocyte levels at all three times, and exhibited lower CD3+, CD4+, CD3+/CD45 RO T-cell and natural killer cell counts than medically treated patients awaiting transplantation 2 months after the LVAS implantation/listing decision. In comparison to controls, both groups had higher levels of imflammatory activation and lower levels of immunocompetence at all three times. Conclusions: While both groups of endstage heart failure patients show immunological alterations compared to controls, patients who have to be bridged by the Novacor LVAS exhibit a more pronounced activation of inflammatory markers. This may be due to more advanced heart failure but the device itself also may contribute to more pronounced inflammation and a temporary suppression of immunocompetent cells.