{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:23:11Z","timestamp":1786116191980,"version":"build-2736575974"},"reference-count":57,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T00:00:00Z","timestamp":1785974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cardiovasc. Med."],"abstract":"<jats:p>Non-ST-segment elevation acute coronary syndrome (NSTE-ACS) represents a major subtype of acute coronary syndrome (ACS). A clinically relevant but often overlooked subgroup of patients presents with typical ischemic symptoms despite a normal initial 12-lead electrocardiogram (ECG), creating real diagnostic difficulty. This narrative review synthesizes current evidence across several domains: epidemiology, pathophysiology, clinical presentation, diagnostic evaluation, and management of NSTE-ACS patients with normal ECGs. A structured literature search of PubMed, Web of Science, and the China National Knowledge Infrastructure (CNKI) databases, with emphasis on prospective cohort studies, registries, systematic reviews, meta-analyses, and current European Society of Cardiology (ESC) and American College of Cardiology\/American Heart Association (ACC\/AHA) guideline recommendations. Depending on the definition of \u201cnormal ECG\u201d and study population, approximately 1%\u20138% of confirmed NSTE-ACS patients present with a normal initial ECG. These patients frequently exhibit single-vessel disease, non-obstructive coronary artery disease, or alternative mechanisms such as coronary vasospasm and microvascular dysfunction. High-sensitivity cardiac troponin (hs-cTn) assays using rapid 0\/1-h or 0\/2-h algorithms constitute the diagnostic cornerstone, while coronary computed tomography angiography (CCTA) provides valuable anatomical assessment, particularly in low-to-intermediate-risk patients. This review presents an integrated diagnostic algorithm, critically evaluates the complementary roles of multimodality imaging techniques, and discusses future directions including artificial intelligence-assisted ECG interpretation and wearable monitoring technologies.<\/jats:p>","DOI":"10.3389\/fcvm.2026.1835982","type":"journal-article","created":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T07:55:23Z","timestamp":1786002923000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical characteristics and diagnostic challenges of non-ST-segment elevation acute coronary syndrome patients with normal electrocardiograms: a review"],"prefix":"10.3389","volume":"13","author":[{"given":"Yiwen","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Cardiology, Affiliated Hospital of Qinghai University","place":["Xining, 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