Impacts of intensive insulin therapy in patients undergoing heart valve replacement

Cardiac surgery with cardioplegic cardiac arrest and cardiopulmonary bypass (CPB) is associated with severe stress response, systemic inflammatory response, and injury. This study was designed to investigate the effects of intensive insulin therapy on patients undergoing valve replacement with CPB.

One hundred nondiabetic inpatients undergoing valve replacement were randomly assigned to a control group or an intensive insulin therapy (IT) group. Plasma cytokine and cardiac troponin I (cTnI) levels were monitored perioperatively.

Compared with the control group, the IT group had smaller increases in plasma concentrations of tumor necrosis factor α, interleukin 1β (IL-1β), IL-6, and cTnI, and had a more pronounced increase in IL-10 levels after the initiation of CPB. After surgery, the required inotropes were reduced in the IT group. In the IT group, the time of artificial ventilation and the postoperative length of stay in the hospital were markedly shortened; however, there were no significant differences between the IT and control groups in mortality and the rate of nosocomial infections of deep sternal wounds.

IT can significantly attenuate the systemic inflammatory response and improve a damaged cardiac function, but it does not reduce the in-hospital mortality rate.