Pulmonary embolism

Acute coronary syndrome

Artery

Cardiology

Psychiatry

Coronary arteries

Radiology

Emergency department

Myocardial infarction

Internal medicine

Chest pain

Medicine

European Journal of Radiology Open

Rationale and ObjectivesTo evaluate the frequency and relevance of hypodense myocardium (HM) encountered in patients undergoing chest-pain CT in the emergency department (ED).Material and MethodsIn this IRB-approved retrospective study, ECG-gated chest-pain CT examinations of 300 consecutive patients (mean age 60 ± 17 years) presenting with acute chest-pain to our ED were evaluated. Once ST-segment elevation infarction was excluded, chest-pain CT including the coronary arteries (rule-out acute coronary syndrome (ACS), pulmonary embolism (PE) and acute aortic syndrome (AAS): chest-pain CTcoronary, n = 121) or not including the coronary arteries was performed (rule-out PE and AAS: chest-pain CTw/o coronary, n = 179). Each myocardial segment was assessed for the presence of HM; attenuation was measured and compared to normal myocardium.ResultsHM was identified in 27/300 patients (9%): 12/179 in chest-pain CTw/o coronary (7%) and 15/121 in chest-pain CTcoronary (12%). Mean attenuation of HM (40 ± 17 HU) was significantly lower than that of healthy myocardium (103 ± 18 HU, p < 0.001), with a mean difference of 61 ± 19 HU. In 15/27 patients (55.6%) with HM, the final diagnosis was acute MI, and in the remaining 12/27 patients (44.4%) previous MI was found in the patients' history. Chest-pain CTw/o coronary identified HM in 10/15 patients (66.6%) with a final diagnosis of acute MI.ConclusionHM indicating acute MI are often encountered in chest pain CT in the ED, also in chest-pain CTw/o coronary when MI is not suspected. This indicates that the myocardium should always be analyzed for hypodense regions even when MI not suspected.

Chest pain CT in the emergency department: Watch out for the myocardium