Effects of leukocyte-depleted warm blood cardioplegia on cardiac and endothelial function

It has been reported that neutrophils and platelets have deleterious effects on myocardium and endothelium during and after ischemia. In this study we evaluated the effects of a leukocyte-depleting filter (Sepacell PLX, Asahi medical, Tokyo) during warm blood cardioplegia and early reperfusion on cardiac and endothelial function in the blood-perfused rat heart. Hearts (n = 7 per group) from donor rats were excised and perfused with blood at 37 degrees C from a support rat. After 10 min of stabilization, the hearts were arrested for 60 min with warm blood cardioplegia given at 20 min intervals. This was followed by 60 min of reperfusion. A leukocyte-depleting filter was used during the cardioplegia and the initial 10 min of reperfusion in the experimental group (Group F) and it was not used in the control group (Group N). Left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximum rate of left ventricular pressure rise (+dp/dt) and maximum rate of left ventricular pressure fall (-dp/dt) were measured as indices of left ventricular function before and after cardioplegic arrest. Coronary sinus effluent was obtained and the levels of MB isozyme of creatine kinase (CKMB), malondialdehide (MDA), elastase and thromboxane B2 (TXB2) were measured as indices of myocardial and endothelial injury. After 60 min of reperfusion, acetylcholine (Ach.) was administered to the coronary perfusate and the difference of nitric oxide (NO) concentration between inflow and outflow, and coronary blood flow were measured as an indication of endothelial function. Group F showed significantly lower LVEDP than Group N at 10 min of reperfusion. The elastase levels were significantly (p < 0.05) lower and the CKMB levels tended (p < 0.1) to be lower in Group F at 60 min of reperfusion. The administration of Ach. to the coronary perfusate showed significantly (p < 0.05) greater coronary blood flow and NO production in Group F. The results suggested that the use of a leukocyte-depleting filter during warm blood cardioplegia and early reperfusion preserves endothelial function and left ventricular diastolic compliance. The technique may provide beneficial effects by reducing reperfusion injury in patients undergoing cardiac surgery.