PDF(Pubmed)
Abstract：
An electrocardiogram, used to not only assess the rate and rhythm of the heart but also to evaluate for injury to the heart, is performed by attaching 12 leads to the patient\'s body. A myocardial infarction can be mimicked by the misplacement of the leads. A 58-year-old man with long-distance running-associated bradycardia developed postoperative atrial fibrillation with a rapid ventricular response. He converted to normal sinus rhythm after a single oral dose of 30 milligrams of diltiazem; however, the automated reading of the electrocardiogram performed in the hospital showed new changes suggestive of a postero-lateral myocardial infarction, including Q waves in leads I and aVL, as well as early precordial R wave progression with R waves and positive T waves in V2 and V3, and a dominant R wave (R wave to S wave ratio greater than one) in V2. A cardiac work-up was entirely normal: serial troponin levels, thyroid stimulating hormone, echocardiogram, computerized tomography of the chest, and Doppler studies of the extremities. Lead misplacement during the electrocardiogram was suspected during the subsequent evaluation by an astute cardiologist; the findings were diagnostic for a left arm to right arm limb lead reversal. All the changes in myocardial infarction were absent when the electrocardiogram was repeated in the office. Misplacement of leads during an electrocardiogram is not a rare event; therefore, the clinician needs to consider the possibility of improper placement of the leads when evaluating an electrocardiogram. Indeed, emotional distress, additional diagnostic procedures, and potentially harmful procedures may be experienced by the patient from incorrect diagnoses based on electrode misplacement during an electrocardiogram; in addition, there are often increased costs to the patient and the healthcare system. Therefore, in the setting of an incorrect diagnosis attributed to lead misplacement during the performance of an electrocardiogram, the acronym MISFIT (which uses the first letters of the words \"myocardial infarction simulated from improper telemetry\") has been introduced. In conclusion, it is important to emphasize that a MISFIT is characterized by an electrocardiogram \'mis\'diagnosis of a myocardial infarction that does not \'fit\' with the clinical scenario.
摘要：
心电图,不仅用于评估心率和心律，还用于评估心脏损伤，是通过将12根引线连接到患者的身体来执行的。可以通过引线的错位来模仿心肌梗塞。一名58岁的男子与长跑相关的心动过缓发生了术后房颤，心室反应迅速。在单次口服30毫克地尔硫卓后，他转变为正常的窦性心律；然而，在医院进行的心电图自动读数显示了暗示后外侧心肌梗死的新变化，包括导联I和aVL中的Q波，以及在V2和V3中具有R波和正T波的早期心前R波进展，在V2中具有主导R波（R波与S波的比率大于1）。心脏检查是完全正常的:连续肌钙蛋白水平，促甲状腺激素,超声心动图,胸部计算机断层扫描，和四肢的多普勒研究。在随后的评估中，一位精明的心脏病专家怀疑心电图中的导线错位；这些发现可以诊断左臂到右臂的肢体导线逆转。在办公室重复心电图时，所有心肌梗塞的变化均不存在。心电图期间导线的错位并不罕见；因此，在评估心电图时,临床医生需要考虑导联放置不当的可能性.的确,情绪困扰,额外的诊断程序，和潜在的有害程序可能是由病人在心电图期间基于电极错位的错误诊断经验;此外,通常会增加患者和医疗保健系统的成本。因此,在心电图表现过程中由于导线错位而导致的错误诊断中，介绍了缩写词MISFIT（使用单词“通过不正确的遥测模拟的心肌梗塞”的第一个字母）。总之,需要强调的是,MISFIT的特征是心电图对心肌梗死的诊断不符合临床情况.
