Effects of two differently heparin-coated extracorporeal circuits on markers for brain and myocardial dysfunction

The two most commonly used heparin-coated systems for cardiopulmonary bypass (CPB) are the Carmeda Bio-Active Surface (CBAS) (Medtronic, Minneapolis, MN, USA) and the Duraflo II coating (Baxter Healthcare, Irvine, CA, USA). The two surfaces are technically unequal and previous experimental studies have demonstrated disparities in effects on the immune system and blood cells. However, little is known concerning the influence of the two surfaces on markers for brain and myocardial dysfunction. Methods: Forty patients undergoing elective, primary coronary bypass grafting with CPB were prospectively randomized to either the CBAS system or the Duraflo II circuit. During and after CPB, biological markers for brain dysfunction and myocardial injury were analysed. Results: Both markers for brain dysfunction S-100B and neuron-specific enolase (NSE) increased significantly during CPB (p=0.01). The elevation during bypass correlated significantly with the duration of CPB (r=0.39 and r=0.38, respectively, both p<0.02). NSE was somewhat more elevated in the Duraflo II group at the end of CPB (p=0.01) and 5 h after CPB (p=0.02); for S-100B, there were no intergroup differences. Also, the markers related to myocardial injury, myoglobin and creatine kinase (CK-MB) mass increased during CPB (p=0.01), while elevation of troponin-I occurred 5 h after CPB (p=0.01). There were no statistically significant intergroup differences. No significant correlation was seen between the release of cardiac markers and the duration of CPB. The clinical course was similar in both groups. Conclusions: Except for a slightly higher elevation of NSE at the end of CPB and 5 h after CPB in the Duraflo II group, there were no significant differences between the CBAS group and the Duraflo II group concerning markers for brain and myocardial dysfunction.