LAUSR

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Korea Centre for Disease Control and Prevention. Data regarding the incidence, relevant patient factors, and clinical outcomes of the misdiagnosis of ST-elevation myocardial infarction (STEMI) in the modern era of percutaneous coronary intervention are limited. We investigated the incidence, relevant patient factors, and clinical outcomes of the misdiagnosis of STEMI from a nationwide, prospective Korean registry of acute myocardial infarction. Out of 28,470 patients with acute myocardial infarction between November 2011 and June 2020, 11,796 were eventually diagnosed with STEMI following a coronary angiogram. They were classified into two groups: patients with an initial working diagnosis of STEMI before starting the initial treatment and patients with an initial working diagnosis of non-STEMI (misdiagnosed group). Out of 11,796 patients with a final diagnosis of STEMI, 165 (1.4%) were misdiagnosed. The door-to-angiography time in the misdiagnosed group was five times longer than that in the timely diagnosed group (median 220 [interquartile range 66–1177] vs. 43 [31–58] minutes, P <0.001). In a multivariable adjustments model, patients with a history of heart failure, atypical chest pain, anaemia, or symptom-to-door time ≥4 hours had significantly higher odds, whereas those with systolic blood pressure <100 mmHg or anterior ST-elevation or left bundle branch block on electrocardiogram had lower odds of STEMI misdiagnosis (Figure 1). For patients with culprit lesions in the left anterior descending artery (n = 5838), the adjusted one-year mortality risk for STEMI misdiagnosis was 1.84 (95% confidence interval 1.01–3.38; Figure 2). Misdiagnosis of STEMI is not uncommon and is associated with a significant delay in coronary angiography, resulting in an increased one-year mortality for patients with culprit lesions in the left anterior descending artery.