Cauliez B, Redonnet M, Darras S, Blanchet D, Ménard J-F, Bessou J-P, Lavoinne A
Service de biochimie médicale, CHU Rouen.
Ann Biol Clin (Paris). 2004 Jan-Feb;62(1):41-6.
Cardiac troponin I (cTnI) assay is used in the diagnosis of myocardial infarction after cardiac surgery. Variations in the cut-off value have been reported even with the same assay method. The aim of this work is to investigate the release profile of cTnI and CK-MB mass after cardiac surgery and to determine the cut-off value of cTnI and CK-MB mass allowing the diagnosis of perioperative myocardial infarction. In patients without postoperative cardiac complication, the cTnI peak was observed 24 hours after surgery both in coronary artery bypass grafting and in valve replacement. Moreover, the amount of cTnI released within the three hours after surgery is 2.5 fold higher in valve replacement than in coronary artery bypass grafting. The CK-MB peak was observed 3 hours after surgery in the two surgical procedures. In these patients, cTnI and CK-MB concentrations increased with the cross clamp time duration. In patients with postoperative myocardial infarction, the cTnI and CK-MB peaks were observed 24 hours after surgery. Diagnosis of perioperative myocardial infarction can be performed with a sensitivity of 100% at 24 hours with cut-off values of 32 and 7 microg/L for CK-MB and cTnI, respectively, both with Stratus (Dade Behring) and Immulite (DPC) analysers.
心肌肌钙蛋白I（cTnI）检测用于心脏手术后心肌梗死的诊断。即使采用相同的检测方法，也有报道称临界值存在差异。这项研究的目的是调查心脏手术后cTnI和肌酸激酶同工酶质量（CK-MB mass）的释放情况，并确定cTnI和CK-MB mass的临界值，以用于围手术期心肌梗死的诊断。在无术后心脏并发症的患者中，冠状动脉搭桥术和瓣膜置换术后均在术后24小时观察到cTnI峰值。此外，瓣膜置换术后手术3小时内释放的cTnI量比冠状动脉搭桥术高2.5倍。两种手术中均在术后3小时观察到CK-MB峰值。在这些患者中，cTnI和CK-MB浓度随阻断时间延长而增加。在有术后心肌梗死的患者中，术后24小时观察到cTnI和CK-MB峰值。使用Stratus（达德拜林公司）和Immulite（DPC公司）分析仪，分别以32和7μg/L作为CK-MB和cTnI的临界值，在术后24小时诊断围手术期心肌梗死的敏感性可达100%。
