异氟醚预处理对体外循环后QT离散度的影响

观察体外循环心脏停跳心内直视手术过程中异氟醚预处理对患者QT离散度 (QTd)的影响并探讨其意义。2 0例瓣膜置换术患者 (ASA2～ 3级 ) ,随机分为预处理组和对照组。分别于麻醉后 (T1)、主动脉开放后 15min(T2 )、2h(T3 )、2 4h(T4)时间点取血样 ,检测血清心钠素 (ANP)、心肌钙蛋白I(cTnI)浓度 ;另于术前、术后第 1,3天记录同步 12导联心电图 ,测量QTd和校正QTd(QTcd)。结果 :术后两组QTd和QTcd较术前显著增加 (P <0 .0 1) ,其中对照组增加尤为显著 ,且第 1天时QTd和QTcd值大于预处理组 (70 .38± 8.34msvs 6 0 .84± 9.15ms,89.94± 7.6 5msvs81.6 8± 8.2 3ms,P均 <0 .0 5 ) ;两组ANP于T2 、T3 时有显著升高 (P <0 .0 1) ,且T3 时预处理组明显高于对照组 (5 5 7.89± 84 .0 3pg/mlvs 4 82 .38± 73.4 4 pg/ml,P <0 .0 5 ) ;T3 、T4时 ,对照组cTnI显著高于预处理组 (0 .19± 0 .0 5ng/mlvs0 .13± 0 .0 2ng/mL ,0 .2 4± 0 .0 7ng/mlvs 0 .18± 0 .0 4ng/ml,P <0 .0 1或 0 .0 5 )。结论 :异氟醚预处理能缩短QTd和QTcd ,其机制可能与其减少心肌损伤有关。

Effect of Isoflurane Perconditioning on QT Dispersion After Cardiopulmonary Bypass

To observe the change and significance of QT dispersion(QTd) in patients undergoing cardiopulmonary bypass after isoflurane perconditioning,twenty patients undergoing valve replacement(ASA 2～3) were divided randomly into two groups: isoflurane preconditioning group(I group) and control group(C group). The serum ANP, cTnI at post-anesthesia induction(T 1) and fifteenth minute(T 2), two hours(T 3), 24 hours(T 4) after reperfusion were detected and electrocardiograms were recorded before operation and first, third day after operation. Results: The QTd and QTcd of two groups were significantly increased after operation( P <0.01); that of C group was increased more and at first day was markedly higher than of I group(70.38±8.34 ms vs 60.84±9.15 ms,89.94±7.65 ms vs 81.68±8.23 ms, P <0.05 respectively). ANP of two group were significantly increased at T 2,T 3( P <0.01), and that of I group was higher than C group at T 3(557.89±84.03 pg/ml vs 482.38±73.44 pg/ml, P <0.05);cTnI of C group was higher than I group at T 3,T 4. Conclusion: Isoflurane preconditioning could shorten QTd and QTcd, It could be related to reducing myocardial ischemical reperfusion injury.