Chest Pain in an Out‐of‐Hospital Emergency Setting: No Relationship Between Pain Severity and Diagnosis of Acute Myocardial Infarction

Background Chest pain frequently prompts emergency medical services ( EMS ) call‐outs. Early management of acute coronary syndrome ( ACS ) cases is crucial, but there is still controversy over the relevance of pain severity as a diagnostic criterion. Study objective The aim of this study was to determine whether there is a relationship between the severity of chest pain at the time of out‐of‐hospital emergency care and diagnosis of acute myocardial infarction ( AMI ). Methods This was a subsidiary analysis of prehospital data collated prospectively by EMS in a large suburb. It concerned patients with chest pain taken to hospital by a mobile intensive care unit. Pain was rated on EMS arrival using a visual analog, numeric or verbal rating scale and classified on severe or not severe according to the pain score. A diagnosis of AMI was confirmed or ruled out on the basis of 2 plasma troponin measurements and/or coronary angiography results. Results Among the cohort of 2,279 patients included, 234 were suitable for analysis, of which 109 (47%) were diagnosed with AMI. The rate of severe pain on EMS arrival was not significantly different between AMI patients and no myocardial infarction patients (49% [95% CI 40 to 58] and 43% [34 to 52], respectively; P  = 0.3; odds ratio 1.3 [0.8 – 2.3] after adjustment for age and gender). Conclusion In our out‐of‐hospital emergency setting, the severity of chest pain was not a useful diagnostic criterion for AMI.