[Prehospital assessment and treatment decisions of a suspected acute coronary syndrome: what are the problems? Results of the "Emergency Doctor and Acute Myocardial Infarction" study (NAAMI)].

BACKGROUND: Interpretation of prehospital 12-lead electrocardiograms (ECG) in acute ST-elevation myocardial infarction (STEMI) remains a diagnostic challenge in many cases. The aim of this study was to determine whether board-certified emergency physicians (BCEP) are able to distinguish STEMI from non-STEMI in a large proportion of cases, thus assuring more precise prehospital triage and treatment.

METHODS: Electrocardiograms of eight patients with acute non-traumatic chest pain (with 6 ECGs demonstrating STEMI, one with pericarditis, and one with pulmonary embolism) were assessed in a blinded fashion by 73 BCEP (19 female, mean age 37 +/- 5.3 years). Decisions had to be made by them regarding the diagnosis (STEMI or not) and treatment (immediate reperfusion or transfer to the nearest hospital without facilities for percutaneous coronary intervention).

RESULTS: In the ECGs with STEMI 83% of BCEPs made the correct diagnosis without significant differences between the subgroups. But in cases of non-STEMI-ECG only 30% of BECP made the correct diagnosis. The results in interpreting non-STEMI were better in older (> 50 years) BCEPs and in those with a background in internal medicine (p = 0.045, and p = 0.01, respectively). In case of STEMI 75% of BCEPs initiated the correct therapy, without significant differences between the subgroups. In case of non-STEMI ECG only 33% of BECPs made the correct diagnosis. Also, the therapeutic decisions in case of non-STEMI were better in older (> 50 years) BCEPs and in those with a background in internal medicine (p = 0.04, and p = 0.02 respectively).

CONCLUSION: In cases of acute non-traumatic chest pain the interpretation of the electrocardiogram by prehospital emergency doctors give to unsatisfactory results. The present study suggests, that additional training in ECG interpretation may be a critical component of the education of physicians who care for patients presenting with acute coronary syndrome.