Effect of sialyl Lewis(x) selectin blockade on myocardial protection during cardioplegic arrest and reperfusion

Put-pose: Selectins play a crucial role in the neutrophil-mediated myocardi al injury associated with ischemia/reperfusion. We investigated the effect of selectin inhibition on neutrophil-endothelial cell adhesion, myocardial water content, and left ventricular (LV) recovery after cardiopulmonary byp ass (CPB) and cardioplegia. Methods: Dogs were subjected to CPB and 60 minutes of hypothermic cardiople gia. A selectin inhibitor (SI) (25 mg/kg) was given five minutes prior to C PB and as a continuous infusion (5 mg/kg/h) throughout CPB (n = 6). Saline- treated controls (n = 6) received identical volumes. Preload recruitable st roke work (PRSW) was calculated by sonomicrometry and micromanometry Myocar dial water content was determined by microgravimetry. Myeloperoxidase (MPO) activity was measured to quantify polymorphonuclear neutrophil (PMN) infil tration. Results: Sl did not attenuate PRSW as well as post-CPB MPO tissue activity. While we found no difference in myocardial water gain between groups 120 m inutes post-CPB, there was better edema resolution with SL Conclusions: Selectin antagonism does not reduce CPB-associated myocardial injury, and contractile recovery is not enhanced.