Effects Of Sevoflurane-induced Postconditioning On Neutrophil Infiltration And Serum Troponin T Concentrations In Patients With RHD During Valve Replacement Surgery

ObjectiveThis study is designed to investigate the effects of sevoflurane postconditioning on serum troponin T concentrations (cTnT) and myocardial infiltration of polymorphonuclear neutrophils (PMN) during adults heart valve replacement surgery, and to explore the myocardial protection of sevoflurane and its relationship with the PMN aggregation in myocardial tissue.Methods24 patients with rheumatic valvular heart disease (RHD), classified as ASAⅡ-Ⅲ, NYHAⅡ-Ⅲ, and scheduled for single valve replacement surgery under cardiopulmonary bypass(CPB) were enrolled and divided randomly into control group (C group, n=12) and sevoflurance group (S group, n=12). All patients were anesthetized and managed in the same way. EEG, BP, SpO2, MAP, CVP, PETCO2, PETsevoflurane, blood electrolytes, blood gas analysis were monitored routinely. After the aorta and vena cava declamping, mechanical ventilation was initiated with 1 MAC of sevoflurane inhalation for 10 min in S group. Arterial blood samples,3ml/per time, were collected before surgery and at 1 hour,2 hours,4 hours after aortic declamping for test of serum troponin T concentrations.0.5 cm×0.5 cm×1 cm of atrial tissue were taken after opening the pericardium (No) and before closed pericardium (N1) for immuno-histochemical analysis.Results(1) Serum cTnT concentration:Comparing with baseline(T1), it increased markedly at T2, T3, T4 in both groups(p<0.05). No statistical difference at T1 between two groups(p>0.05), however it was much lower at T2, T3, T4 in test group than in the control (p<0.05).(2) PMN aggregation in myocardial tissue:Comparing with PMN density before surgery (SN0), PMN expression elevated remarkably after aorta declamping (SN1)in both groups (p<0.05). There was no statistical difference between CN0 and SN0 (p>0.05), however SN1 was lower than CN1 (p<0.05).ConclusionSevoflurane postconditioning can attenuate myocardial ischemia-reperfusion injury during valve replacement under CPB in adult patients with RHD. Its myocardial protection may be related to reduced PMN activation, infiltration and aggregation into the myocardium.