T cells in ventricular assist device patients

Levels of T lymphocytes were measured in 20 consecutive patients, 18 men and two women, supported with ventricular assist devices or an artificial heart. Indications for support were bridge to transplantation (n = 10), postcardiotomy cardiogenic shock (n = 8), and acute myocardial infarction shock (n = 2). Control levels were from healthy volunteers not undergoing cardiac operation. Preoperatively, numbers of total lymphocytes and subclasses CD3, CD4, and CD8, as well as the interleukin-2 receptors (IL2R), were the same as controls (cells/microliters): lymphocytes, 1,940; CD3, 1,413 +/- 410; CD4, 894 +/- 318; CD8, 490 +/- 185; IL2R, 96. From implant to postoperative day 5, levels were below control values (p less than 0.001), reaching a nadir on postoperative day 2 (lymphocytes, 896 +/- 599; CD3, 489 +/- 267; CD4, 309 +/- 207; CD8, 183 +/- 107; IL2R, 43 +/- 47). Data from 10 patients (group 1) who survived (four weaned from cardiopulmonary bypass, six transplanted) were compared with those from 10 patients (group 2) who died of multiorgan failure, sepsis, or both. From preimplant through postoperative day 6, levels did not differ between groups. However, from postoperative day 7 to the last day of ventricular support (group 1, 24-90 days; group 2, 7-29 days), group 1 levels (lymphocytes, 2,364 +/- 618; CD3, 1,825 +/- 553; CD4, 1,013 +/- 187; CD8, 796 +/- 402) were significantly above (p less than 0.01) group 2 levels (lymphocytes, 1,290 +/- 463; CD3, 746 +/- 295; CD4, 534 +/- 253; CD8, 221 +/- 106). These data indicate that lymphocytes and particularly T cells 1) decrease after ventricular assist device insertion, reaching a nadir at postoperative day 2, 2) return to control values after patients whose clinical status improves, and 3) remain low in severely ill patients. T-cell depression in ventricular assist device patients is related to the severity of the patient's condition rather than the presence of the device.