逆行性灌注浅低温氧合血心脏不停跳与冷血心脏停搏液对cTn I的影响

目的　对比研究逆行性灌注浅低温氧合血心脏不停跳与低温冷血心脏停搏液对外周血清心肌肌钙蛋白 I(c Tn I)的影响。　方法　将 18例双瓣膜置换术患者分为心脏不停跳组和心脏停搏组 ,观察围手术期外周血清c Tn I、肌酸激酶 (CK)、肌酸激酶同工酶 (CK- MB)及主动脉阻断前后用透射电子显微镜观察心肌超微结构变化。结果　心脏不停跳组主动脉开放后各个时相点 CK虽略低于心脏停搏组 ,但差别无显著性意义 (P>0 .0 5 ) ;主动脉开放后 6小时 CK- MB明显低于心脏停搏组 (P<0 .0 5 ) ,主动脉开放后各个时相点心脏不停跳组 c Tn I明显低于心脏停搏组 (P<0 .0 5 )。两组患者主动脉阻断前心肌超微结构均有轻度改变 ,主动脉阻断 90分钟心脏停搏组心肌超微结构损伤较心脏不停跳组明显。　结论　逆行性灌注浅低温氧合血心脏不停跳围手术期外周血清 c Tn I较低 ,可能与该方法使体外循环期间发生不可逆损伤的心肌细胞较少 ,心肌超微结构损伤较轻有关。

Effects of Retrograde Perfusion Tepid Oxygenated Blood While Heart Beating and Cold Blood Cardioplegia on Cardiac Troponin I

Objective To evaluate the influence of continuous retrograde perfusion tepid oxygenated blood while heart beating compared with cold blood cardioplegia on serum cardiac troponin I (cTn I). Methods Eighteen patients subjected to double valve replacement were assigned to beating-heart group ( n =9) and arrested-heart group ( n =9). Levels of creatine kinase (CK), creatine kinase isoenzyme-MB (CK-MB) and cTn I in serum were measured and myocardial ultrastructure was observed before and during aortic cross-clamping. Results No difference of serum CK was seen between the two groups after aortic cross-clamp removing ( P >0.05). The level of serum CK-MB at 6 hours after aortic cross-clamp removing was significantly lower in beating-heart group than that in arrested-heart group ( P <0.05). The level of serum cTnI was distinctly lower in beating-heart group than that in arrested-heart group ( P <0.05). Atrial septum ultrastructure was slightly changed before aortic cross-clamping in the two groups. It was damaged more seriously in arrested-heart group at 90 minutes after aortic cross-clamping than that before aortic cross-clamping, however no patent injury was observed in beating-heart group. Conclusion Level of cTnI in beating-heart group was lower than those in arrested-heart group. It seems due to well maintaining myocardial ultrastructure.