卡维地洛对陈旧性心肌梗死兔室颤阈值及心室不应期的影响  

Effect of carvedilol on ventricular fibrillation threshold and refractory period in rabbits with healed myocardial infarction

作　　者：牛惠燕[1] 刘念[1] 李泱[1] 周强[1] 张存泰[1] 卜军[1] 阮燕菲[1] 陆再英 

机构地区：[1]华中科技大学同济医学院同济医院心内科,武汉430030

出　　处：《中华心血管病杂志》2003年第12期941-944,共4页Chinese Journal of Cardiology

摘　　要：目的　研究卡维地洛长期口服给药后陈旧性心肌梗死 (healedmyocardialinfarction ,HMI)梗死边缘区 (infarctionborderzone ,IBZ)和远离梗死区 (infarctionremotezone,IRZ)不应期及不应期离散度的变化及与室颤阈值的关系。方法　 30只家兔按体重随机分为三组 ,HMI组 (10只 ) :结扎冠状动脉左回旋支 ,喂养 3个月 ;卡维地洛组 (10只 ) :手术同HMI组 ,术前当天开始服用卡维地洛0 33mg·kg-1 d-1,共 3个月 ;假手术组 (10只 ) :手术同HMI组 ,但不结扎冠状动脉。 3个月后在体测定室颤阈值 ,在整体心脏Langendorff灌流下记录IBZ和IRZ的有效不应期 ,并检测心脏重量、室壁厚度及左室最大内径等 (假手术组IBZ和IRZ取与HMI组相应的区域 )。结果　 (1)在相同周长起搏下HMI组有效不应期较假手术组均显著性延长 ,75 0ms周长时为IBZ(2 16 9± 4 6 )ms比 (16 0 0±3 8)ms ,IRZ(2 0 5 6± 5 6 )ms比 (16 1 3± 3 5 )ms,P <0 0 1;卡维地洛组有效不应期较HMI组显著性缩短 ,P <0 0 1,在 75 0ms周长时为IBZ(179 2± 9 7)ms、IRZ(175 0± 7 7)ms。 (2 )HMI组室颤阈值较假手术组显著性降低 [(9 16± 1 2 3)V比 (13 3± 2 1)V ,P <0 0 5 ];卡维地洛组室颤阈值较HMI组显著性升高 [(11 8± 1 4 )V比 (9 16± 1 2 3)V 。Objective To investigate effects of carvedilol on ventricular fibrillation threshold and disperse of refractory period in infarction border zone(IBZ) and infarction remote zone(IRZ) of rabbit heart with healed myocardial infarction(HMI). Methods 30 rabbits were randomly assigned into three groups: HMI group, ligation of the circumflex coronary artery;carvedilol group, same operation as HMI group, and administration of oral carvedilol 0.33 mg·kg -1 ·d -1 ×3m beginning on the day of operation; Sham group,left thoracotomy but no coronary artery ligation. Three months after surgery, rabbits were harvested for the detect of VFT in vivo?effective refractory period in vitro through Langendorff-perfusion and heart weight?thickness of ventricular wall? maximum perimeter of left ventricular chamber and infarction size were mearured. Results (1) When R-R interval is 750 ms, effective refractory periods in HMI group [IBZ(216.9±4.6) ms, IRZ(205.6±5.6) ms] were increased significantly compared with those in Sham group[IBZ(160.0±3.8) ms, IRZ(161.3±3.5) ms], P <0.01;effective refractory periods in carvedilol group[IBZ (179.2±9.7) ms, IRZ(175.0±7.7) ms] were significant lower than those in HMI group, P <0.01. (2) Ventricular fibrillation threshold in HMI group was (9.16±1.23)V which was decreased significantly compared with that (13.3±2.1)V in Sham group, P <0.05;ventricular fibrillation threshold in carvedilol group was significantly increased (11.8±1.4) V compared with that in HMI group, and similar to Sham group. (3) Whole heart weight (WHW)? WHW/body wight? thickness of IRZ ventricular wall and the maximum perimeter of left ventricular chamber in HMI group were all increased compared with those in Sham group, P <0.05;In carvedilol group, the changes of above parameters and the infarct size were significantly alleviated, P <0.05. Conclusion Carvedilol could reverse not only ventricular remodeling but also the abnormal prolongation of effective refractory period in rabbit heart with HMI, and i

关 键 词：卡维地洛 陈旧性心肌梗死 兔 心室不应期 心室颤动 肾上腺素能Β受体拮抗剂 

分 类 号：R542.22[医药卫生—心血管疾病] R972[医药卫生—内科学]