Clinical profile of acute myocardial infarction: the Registry of Acute Medical Emergencies registry.

INTRODUCTION

Around 30% of patients with acute myocardial infarction do not report chest pain, but data on symptom patterns according to the type of myocardial infarction and attending physician specialty are scarce.

OBJECTIVE

The aim of this study was to identify common clinical presentations of acute myocardial infarction in a Brazilian registry, stratified by infarction type and physician specialty.

METHODS

Observational analysis of two datasets: (1) retrospective cohort of 2,783 acute myocardial infarction patients from 15 hospitals (2014-2018) initially evaluated by emergency physicians; (2) prospective registry of 718 acute myocardial infarction patients (2018-2020) assessed in the acute phase by cardiologists via telemedicine. Cases were classified as ST-segment Elevation Myocardial Infarction or Non-ST-segment Elevation Myocardial Infarction. Symptoms were categorized as typical/atypical chest pain, epigastric pain, or absence of both; additional symptoms were recorded. Categorical variables were compared using chi-square tests (p<0.05).

RESULTS

Typical chest pain occurred in 60.3% of patients, more frequent in ST-segment Elevation Myocardial Infarction than Non-ST-segment Elevation Myocardial Infarction (66.5 vs. 56.5%; p<0.01). Absence of chest/epigastric pain was more common in Non-ST-segment Elevation Myocardial Infarction (6.1%) than ST-segment Elevation Myocardial Infarction (2.7%) (p<0.01). Cardiologist assessment identified more acute myocardial infarction cases without chest/epigastric pain than emergency physician assessment (11.0 vs. 3.2%; p<0.01). ST-segment Elevation Myocardial Infarction patients without chest/epigastric pain had the highest mortality (29.4%) in the emergency physician cohort.

CONCLUSION

In this registry, absence of chest or epigastric pain was less frequent than previously reported but associated with high mortality. Telemedicine evaluation by cardiologists identified a greater proportion of pain-free acute myocardial infarction presentations.

CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02753023.