瑞芬太尼对兔心肌动作电位及跨室壁复极离散度的影响

Effects of remifentanil on monophasic action potential and transmural dispersion of repolarization in rabbit myocardium

目的：观察瑞芬太尼对兔心肌动作电位及跨室壁复极离散度的影响。方法：成年家兔18只，体重2.0～2.5 kg，制备Langendorff离体心脏灌注模型，K-H液平衡灌注15 min后随机分为3组（n＝6）：正常对照组（C组）继续灌注37℃K-H液60 min；瑞芬太尼组（ R组）灌注含12μg／L瑞芬太尼的K-H液60 min；瑞芬太尼＋氨茶碱组（ RA组）灌注含12μg／L瑞芬太尼＋30 mg／L氨茶碱的K-H液60 min。记录平衡灌注15 min （ T0）、继续灌注15 min （ T1）、30 min （ T2）和60 min （ T3）时心率（ HR）和左心室前壁3层心肌单相动作电位（ MAP），计算单相动作电位复极90％的时程（ MAPD90）和跨室壁复极离散度（ TDR）。记录早期后除极、延迟后除极及心律失常的发生情况。结果：与T0比较，R组T1～T3时HR减慢，MAPD90延长，TDR增大（ P＜0.05）。与C组和RA组比较，R组HR减慢时，MAPD90延长，TDR增大（P＜0.05）。结论：瑞芬太尼减慢HR时，MAPD90延长，TDR增大，折返激动易于发生；氨茶碱增快HR，缩短MAPD90，从而使TDR减小。

AIM：To study the effect of remifentanil on monophasic action potential and transmural dispersion of repolarization （TDR） in the 3-layer myocardium of isolated rabbit hearts .METHODS：Adult rabbits （n=18, 2.0 ～2.5 kg） were used to isolate the hearts for preparing Langendorff perfusion model .The hearts were randomly divided into 3 groups after perfusion with K-H solution for 15 min： the perfusion in control group （ C group ） continued for 60 min; the hearts in remifentanil group （ R group ） were perfused with 12 μg/L remifentanil K-H solution for 60 min; the hearts in remifentanil＋aminophylline group （ RA group ） were given 60-min perfusion of 12 μg/L K-H remifentanil ＋30 mg/L aminophylline .The HR and 3 layers of myocardial monophasic action potential （ MAP） in the left ventricular anterior wall were recorded at time points after balanced infusion for 15 min （ T0 ） , and continued perfusion for 15 min （ T1 ） , 30 min （ T2 ） and 60 min （ T3 ） .The monophasic action potential duration of repolarization at 90%（ MAPD90 ） and the transmural dispersion of repolarization （TDR） were calculated.The early afterdepolarization, delay afterdepolarization and arrhythmia were also observed.RESULTS：In R group, slower HR and prolonger MAPD90 and TDR at T1 ~T3 were observed as com-pared with those at T0（P〈0.05）.R group showed slower HR and longer MAPD 90 and TDR than C group and RA group （P〈0.05）.CONCLUSION：Remifentanil slows the HR, extends the MAPD90 and increases the TDR, thus being prone to induce reentry.Aminophylline makes HR faster and MAPD90 shorter, thereby reducing the TDR.