心肌肌钙蛋白Ⅰ测定对判定体外循环心内直视手术心肌损伤的价值

Application of Cardiac Troponin I to the Diagnosis of Myocardial Injury during Open Heart Surgery under Cardiopulmonary Bypass

目的探讨心肌肌钙蛋白I(cTnI)的测定对体外循环心内直视手术心肌损伤的判定价值。方法40例心脏瓣膜置换手术患者随机分为两组,冷晶体停跳液组(A组),温血停跳液组(B组),每组20例,分别于围术期多时点采取中心静脉血,测定血清cTnl、CK及CK—MB的水平。结果术前两组患者的cTnI、CK及CK—MB水平均在正常范围,开放主动脉后1h至术后24h达峰值,其后缓慢下降。术后24h、48h B组cTnI水平明显低于A组(P＜0．05)。CK—MB在开放主动脉后1hB组低于A组(P＜0．05)。cTnI峰值浓度与主动脉阻时间呈直线正相关(P＜0．05)。结论cTnI判定心内直视手术围术期心肌损伤的敏感性及特异性明显优于CK、CK—MB,对围术期心肌缺血损伤的诊断、预后及心肌保护效果的评价具有重要的临床价值。

Objective To evaluate the clinical value of cardiac troponin I （cTnI） in the diagnosis of myocardial injury during open heart surgery under cardiopulmonary bypass （CPB）. Methods Forty patients under - going cardiac vaivular replacement operation were randomly divided into two groups ： Cold crystalloid ardioplegia （ group A, n = 20） and Warm blood cardioplegia （ group B, n =20）. The central venous blood samples were taken at various times during perioperative to measure the serum levels of cTnI, CK - MBand CK. Results cTnI, CK and CK - MB levels were normal before operation, increased markablely following aorta unclamping, reached the peak lh after aorta unclamping to 24h after operation, and decreased progressively to be normal in two groups. The serum cTnI level was significantly lower in group B than that in group A 24h and 48h after operation. The serum CK - MB activity was lower in group B than that in group A 1 h after aorta unclamping. There was positive significant correlation between aorta cross -clamping time and cTnI peak level. Conclusion cTnI can be used to evaluate the degree of myocardial injury and myocardial protective effect in open heart surgery during CPB. As indicators for reflecting the myocardial injury, the sensitivity and specificity of cTnI are more valuable than those of myocardial enzymes.