Cardiac Medical Unit, Grantham Hospital, Hong Kong, ROC.
Ann Acad Med Singap. 2012 Jul;41(7):300-4.
A few electrocardiographic criteria have been described to identify the infarct-related artery in inferior myocardial infarction. The aim of this study was to devise an arithmetic score to further improve the diagnostic accuracy.
From 2004 to 2006, 78 patients who underwent primary angioplasty for inferior myocardial infarction within 6 hours from symptom onset were recruited for electrocardiographic and angiographic analysis.
The mean age of patients was 65 ± 12 years with male predominance (74%). Less ST depression in lead I and aVL, and more prominent ST depression in lead V1-3 were observed in left circumflex artery (LCX) than right coronary artery (RCA) occlusions. In addition, more prominent ST depression in lead I and ST elevation in V1 were found in proximal RCA than distal RCA occlusions. Based on the findings, the Jeopardised Inferior Myocardium (JIM) score was constructed and defi ned as [II-V3/III+V1- I]. The sensitivity and specificity of JIM score ≤0.5 to predict proximal RCA occlusions; 0.5 <JIM score ≤1.5 to predict distal RCA occlusions; and JIM score >1.5 to predict LCX occlusions were 58% and 85%, 69% and 68%, and 79% and 94%, respectively. The accuracy of prediction is slightly better than the 2 previously reported criteria.
By taking into account more leads, the JIM score is capable of identifying the infarct-related artery with an improved diagnostic accuracy.
已经描述了一些心电图标准来识别下壁心肌梗死中的相关梗死动脉。本研究的目的是设计一个算法评分以进一步提高诊断准确性。
2004 年至 2006 年，招募了 78 名症状发作后 6 小时内行直接经皮冠状动脉介入治疗的下壁心肌梗死患者进行心电图和血管造影分析。
患者的平均年龄为 65 ± 12 岁，男性居多（74%）。左回旋支（LCX）闭塞时，I 导联和 aVL 导联 ST 段压低程度较轻，V1-3 导联 ST 段压低程度较明显；而右冠状动脉（RCA）闭塞时则相反。此外，在 RCA 近段闭塞时，I 导联 ST 段抬高和 V1 导联 ST 段压低更明显。基于这些发现，构建了 Jeopardised Inferior Myocardium（JIM）评分，并定义为[II-V3/III+V1- I]。JIM 评分≤0.5 预测 RCA 近段闭塞的敏感性和特异性分别为 58%和 85%；0.5<JIM 评分≤1.5 预测 RCA 远段闭塞的敏感性和特异性分别为 69%和 68%；JIM 评分>1.5 预测 LCX 闭塞的敏感性和特异性分别为 79%和 94%。预测的准确性略优于前两个报告的标准。
通过考虑更多导联，JIM 评分能够识别相关梗死动脉，从而提高诊断准确性。
