Sevoflurane postconditioning converts persistent ventricular fibrillation into regular rhythm

Background and objective Recent studies showed that ischaemic postconditioning converted persistent ventricular fibrillation to sinus rhythm. The influence of anaesthetic postconditioning on ventricular fibrillation has not yet been determined. In the present study, we studied the possible effect of sevoflurane postconditioning on persistent reperfusion-induced ventricular fibrillation in the isolated rat heart model. Methods Isolated Langendorff-perfused rat hearts (n = 80) were subjected to 40 min of global ischaemia and reperfusion. The hearts with persistent ventricular fibrillation (n = 16) present after 15 min of reperfusion were then randomly assigned into one of the two groups: controls (n = 8), reperfusion was continued for 25 min without any intervention, and sevoflurane postconditioning (n = 8), rat hearts in the sevoflurane postconditioning group were exposed to sevoflurane at a concentration of 8.0% for 2 min followed by 23 min of reperfusion. As for the third group, the rest of the hearts were included in the nonpersistently fibrillating hearts group (n = 64). Left ventricular pressures, heart rate, coronary flow, electrogram and infarct size were measured as variables of ventricular function and cellular injury, respectively. Results Conversion of ventricular fibrillation into regular rhythm was observed in all hearts subjected to sevofluane postconditioning. Regular beating was maintained by all anaesthetic postconditioned hearts during the subsequent reperfusion. None of the hearts in the control group had normal rhythm at the end of the experiment. At the end of reperfusion, the coronary flow was increased in sevoflurane postconditioned hearts compared with the hearts that did not develop persistent ventricular fibrillation. Conclusion Sevoflurane postconditioning possesses strong antiarrhythmic effect against persistent reperfusion-induced ventricular fibrillation. Anaesthetic postconditioning may have the potential to be an antiarrhythmic therapy for reperfusion-related arrhythmias. Eur J Anaesthesiol 26:766-771 (C) 2009 European Society of Anaesthesiology.