Acute myocardial infarction in non-cardiac critically ill patients: a clinical-pathological study

Background: in patients admitted to the Intensive Care Unit (ICU) for non cardiac disease, the diagnosis of acute coronary syndromes can be challenging. The aim of the study was to define the rate of discrepancies concerning the diagnosis of acute myocardial infarction and to evaluate the presence of risk factors that could be helpful in identifying patients at higher risk of missed diagnosis. Methods: we compared clinical and autopsy records of 600 critically ill patients who died in our ICU in a 10-years period. We identified patients in whom acute myocardial infarction was reported as the cause of death on the clinical records or was discovered only at post-mortem examination. These subjects were subsequently divided into two Groups: patients in Group 1 underwent diagnostic evaluation for acute myocardial infarction whereas those in Group 2 were not investigated for. Results: In Group 1, a definite clinical diagnosis was reached in 11 patients (14,7%) but remained undetermined in 37 patients (48%). The diagnosis was totally missed in 8 patients in Group 1 (10,6%) and in 20 patients of Group 2 (26,6%). The diagnostic discrepancy was higher in septic patients, in whom the correct diagnosis of acute myocardial infarction was established at a rate lower than 50% in respect to non-septic patients. Conclusions: Our experience strengthens the role of post-mortem examination as a source of feed-back of the overall diagnostic and therapeutic approach especially in septic patients, where the diagnostic error is more frequent.