Background: The inflammatory responses to the different myocardial protection approaches have not been thoroughly investigated. We sought to study the cytokine responses to cardiopulmonary bypass (CPB) using the intermittent aortic crossclamping with ventricular fibrillation (IAC) versus blood cardioplegic arrest (BC) techniques.
Methods: Perioperative plasma levels of tumor necrosis factor a (TNF-alpha), interleukins (IL) 6, 8, 10, and cardiac troponin-I (cTnI) were measured serially before surgery, at the end of surgery, and 2, 24, and 48 hours after elective coronary revascularization in 31 patients (IAC: n=15; BC: n=16).
Results: Demographics, preoperative status, and number of grafts (IAC: 2.7 +/- 0.6; BC: 3.0 +/- 0.4) were similar between groups. No major complications occurred in either group. The total ischemic time and duration of CPB were shorter in group IAC (17 +/- 5 and 58 +/- 10 min vs 45 +/- 14 and 81 +/- 21 min; both p<0.01). Although the intergroup difference in postoperative cTnI levels was not statistically significant, the release of both TNF-alpha and IL-8 were higher in group IAC than in group BC. However, IL-6 and IL-10 levels were lower after surgery in group IAC.
Conclusion: Despite the duration of ischemia and CPB being shorter, intermittent aortic crossclamping is associated with an enhanced pro-inflammatory but a reduced anti-inflammatory response compared to the cardioplegic arrest technique. Its clinical relevance needs to be further defined.