急性冠脉综合征 (acute coronary syndrome, ACS) 是指一系列急性心肌缺血和/或梗死。根据初始 ECG 上是否存在 ST 段抬高，以及对心肌生物标志物（例如肌钙蛋白或肌酸激酶）的测定，一般可将 ACS 分为 3 个临床类别。[1]Thygesen K, Alpert JS, Jaffe AS, et al. Fourth universal definition of myocardial infarction (2018). Eur Heart J. 2019 Jan 14;40(3):237-269.
https://academic.oup.com/eurheartj/article/40/3/237/5079081
http://www.ncbi.nlm.nih.gov/pubmed/30165617?tool=bestpractice.com
在 ST 段抬高型心肌梗死（ST-elevation myocardial infarction, STEMI）中，ECG 表现为两个或多个解剖上相邻的导联中 ST 段持续抬高。不稳定型心绞痛和非 ST 段抬高型心肌梗死（non-ST-elevation myocardial infarction, NSTEMI）体现了一种连续的病理学改变，其主要不同在于 NSTEMI 患者存在心肌损伤标志物。[2]Amsterdam EA, Wenger NK, Brindis RG, et al. 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;130:e344-e426.
http://circ.ahajournals.org/content/130/25/e344.long
http://www.ncbi.nlm.nih.gov/pubmed/25249585?tool=bestpractice.com
因此，一些指南将不稳定型心绞痛和 NSTEMI 归类为 ”非 ST 段抬高型急性冠脉综合征"。[2]Amsterdam EA, Wenger NK, Brindis RG, et al. 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;130:e344-e426.
http://circ.ahajournals.org/content/130/25/e344.long
http://www.ncbi.nlm.nih.gov/pubmed/25249585?tool=bestpractice.com
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