Goktekin Omer, Melek Mehmet, Gorenek Bulent, Birdane Alpaslan, Kudaiberdieva Gulmira, Cavusoglu Yuksel, Timuralp Bilgin
Cardiology Department, Faculty of Medicine, Osmangazi University, Daire 15, Eskisehir, Turkey.
Chest. 2002 Dec;122(6):2050-4. doi: 10.1378/chest.122.6.2050.
Serum levels of cardiac troponins after external cardioversion (ECV) for atrial fibrillation and atrial flutter are widely investigated, and no increases in cardiac troponin T (cTnT) levels have been reported. However, the effect of ECV on cardiac enzyme release may depend on the type of arrhythmias. Furthermore, ventricular tachycardia (VT) or ventricular fibrillation (VF) could cause release of cardiac enzymes after ECV due to underlying myocardial ischemia, myocardial dysfunction, or more pronounced hemodynamic deterioration during arrhythmia.
The purpose of this study was to determine whether direct current (DC) shock may increase cardiac enzyme levels in patients with coronary artery disease undergoing ECV for VT or VF, so that diagnosis of acute myocardial infarction, which initially presents with VT or VF, can be excluded.
We obtained measurement of cTnT, total creatine kinase (CK), and CK MB isoenzyme (CK-MB) activity before and after ECV in 27 patients (mean +/- SD age, 62 +/- 13 years) with induced VT or VF (22 patients) who required ECV during provocative electrophysiologic testing and who underwent ECV due to VT (5 patients) in the cardiology department. Blood samples were drawn before, and 4 h, 8 h, and 24 h after ECV. The total energy used was 630 +/- 375 J (range, 200 to 1,280 J). CK levels rose to the upper limit of reference range in seven patients (26%), and CK-MB activity was higher than the normal reference range in five patients (19%) after ECV. In contrast, cTnT concentrations remained within the normal range (< 0.1 micro g/L) in all patients. Peak CK and CK-MB activity levels strongly correlated with the total energy delivered.
Elevation of cTnT level after an urgent DC shock strongly indicates the diagnosis of acute myocardial infarction presented with life-threatening arrhythmias, rather than myocardial damage caused by ECV.
心房颤动和心房扑动患者进行体外心脏复律（ECV）后血清心肌肌钙蛋白水平受到广泛研究，尚未有心肌肌钙蛋白T（cTnT）水平升高的报道。然而，ECV对心肌酶释放的影响可能取决于心律失常的类型。此外，室性心动过速（VT）或室性颤动（VF）可能由于潜在的心肌缺血、心肌功能障碍或心律失常期间更明显的血流动力学恶化，导致ECV后心肌酶释放。
本研究旨在确定直流电（DC）电击是否会使因VT或VF接受ECV的冠心病患者心肌酶水平升高，以便排除最初表现为VT或VF的急性心肌梗死的诊断。
我们测量了27例（平均±标准差年龄，62±13岁）诱发VT或VF（22例）患者在ECV前后的cTnT、总肌酸激酶（CK）和CK MB同工酶（CK-MB）活性，这些患者在激发性电生理检查期间需要ECV，并且在心脏病科因VT（5例）接受了ECV。在ECV前、后4小时、8小时和24小时采集血样。总能量使用为630±375 J（范围，200至1280 J）。ECV后，7例患者（26%）的CK水平升至参考范围上限，5例患者（19%）的CK-MB活性高于正常参考范围。相比之下，所有患者的cTnT浓度均保持在正常范围内（<0.1μg/L）。CK和CK-MB活性峰值水平与传递的总能量密切相关。
紧急直流电电击后cTnT水平升高强烈提示诊断为伴有危及生命心律失常的急性心肌梗死，而非ECV导致的心肌损伤。
