顺逆行结合灌注冷停搏液对心肌保护的作用

目的]通过体外循环手术中应用顺逆行结合灌注冷停搏液的研究,为临床提供一种更有效的心肌保护方法.方法]选用1997～1998年连续30例心脏瓣膜置换术病例,随机分为顺逆行结合组16例,首剂顺行灌注,然后经冠状静脉窦持续灌注200mL/h,30min增加灌注200mL,控制灌注压力4.0～5.3kPa(30～40mmHg);顺行灌注组14例,首剂灌注后每20min重复灌注1次.监测桡动脉和冠状静脉窦血的pH值乳酸浓度乳酸摄取率及心肌酶的变化.结果]顺逆行结合组pH值降低程度较顺行灌注组少(P＜0.05);乳酸摄取率顺逆行结合组较顺行灌注组高(P＜0.05);心肌酶释放水平及手术后降低恢复程度,顺逆行结合组较顺行灌注组低及快.结论]顺逆行结合灌注使心肌灌注更均匀,提高心肌细胞在缺血期间的能量利用,减少心肌损害,促进心肌的修复,使心肌得到较好的保护,是一种有效安全的心肌保护方法.

Efficiency of Combined Antegrade and Retrograde Cardioplegia in Myocardial Protection

Objective To study the myocardial protection efficiency in cardiopulmonary bypass used combined antegrade cardioplegia (AC) and retrograde cardioplegia (RC). Methods A total of 30 patients who accepted valve replacement were divided into 2 groups. 16 in AC/RC combined group, 14 in AC group. In AC/RC group cardioplegia was perfused by first dose of AC combined with continuous RC perfusing extra dosage in 30 min. pH value and lactic acid concentration of coronary venous sinus and radial artery,lactate extraction ratio and myocardial enzyme were detected. Results AC/RC group has a lower pH gradient than the AC group (P<0.05) and higher lactate extraction ratio (P<0.05).It also has a lower level of cardiac enzyme release and a higher rate of automatic rebeating compared with AC group. Conclusions Combined method gives benefit to myocardial energy metabolism during ischemic period, lighter myocardial damage and makes quicker recovery. It is an effective and safe method in myocadial protection.