Objective The present study was carried out to estimate whether the remote ischemic preconditioning (RIPC) reduces myocardial injury in the patients undergoing aortic valve replacement (AoVR)
Methods 27 patients were included into the prospective randomised study. In all cases the AoVR was performed due to the aortic stenosis under cardiopulmonary bypass (CPB). 13 patients of the main group received RIPC and 14 patients formed the control group. Anaesthesia was maintained either by propofol and fentanyl (7 patients in the control group, 8 patients in the RIPC group) or by sevoflurane and fentanyl (7 patients in the control group, 5 patients in the RIPC group). RIPC was induced by three 5-min cycles of lower limb ischemia and reperfusion. Troponin I (cTnI) was analysed at baseline, 30 min, 12, 24, 48 h after CPB completion. Quantitative data were presented as median (25th–75th percentile). According to nonparametrically distribution, data were assessed by the Mann-Whitney U-test.
Results We found significant elevation in cTnI levels above baseline in both groups with maximal values at 12 h for control group and at 24 h for RIPC group. There was no statistical difference in cTnI levels between groups at 12 h (2.7 (1.7; 3.8) ng/ml for RIPC group vs. 2.9 (1.5; 6.9) ng/ml for the control group, p = 0.70) and at 24 h (2.4 (1.6; 3.1) ng/ml vs. 3.5 (1.7; 6.9) ng/ml respectively, p = 0.45). The area under the curve (AUC) for cTnI for the RIPC group was equal 122.2 (72.1; 127.4) ng/ml/48 h and did not differ significantly compared with the control group (144.8 (79.8; 251.5) ng/ml/48 h), p = 0.35.
Significant differences in the cTnI levels between the RIPC group and the control one were found only when sevoflurane anaesthesia cases were selected for analysis: those levels were 1.6 (1.5; 2.2) ng/ml vs. 5.5 (4.0; 6.5) ng/ml respectively (p = 0.03) at 24 h and 1.4 (1.3; 1.5) ng/ml vs. 3.2 (2.9; 3.6) ng/ml (p = 0.02) at 48 h. Moreover, in the sevoflurane subgroup the statistical difference was displayed for cTnI AUC: 69.0 (65.8; 97.5) ng/ml/48 h in the RIPC group vs. 250.9 (250.4; 296.6) ng/ml/48 h in the control group, p = 0.02.
There were no statistical differences in the cTnI levels and the cTnI AUC between the RIPC group and the control one in the propofol anaesthesia cases.
Conclusions The data from this pilot study suggest that the cardioprotective effects of RIPC should be evaluated in the selected anaesthesia technique group.