Prevalence of occlusive myocardial infarction in patients diagnosed with non-ST-elevation myocardial infarction at a single private facility in Cape Town, South Africa

Elmari Schoeman, Ibrahim D’Andrea, Willem Stassen

Abstract

Background: ST-elevation myocardial infarction (STEMI) is associated with acute coronary occlusion, while non-ST- elevation myocardial infarction (NSTEMI) is often associated with partial occlusion. However, 25.5% of NSTEMIS involve complete occlusion, impacting mortality and major adverse cardiovascular events (MACE). The occlusive myocardial infarction (OMI) vs. non-occlusive myocardial infarction (NOMI) paradigm aims to improve acute myocardial infarction (AMI) identification.
Objective: To examine OMI prevalence among NSTEMIS in a Cape Town emergency centre in 2019 and evaluate cardiac troponin I (cTnI) levels, angiography rates, thrombolysis in myocardial infarction (TIMI) flow grades, and door-to- angiogram times.
Methods: A retrospective cross-sectional study of 31 NSTEMI patients using descriptive statistics, Chi-square tests, and Mann-Whitney U tests.
Results: OMI was identified in 83.9% (n = 26) of NSTEMIS. Significant cTnI levels (median 1450 ng/L, p = 0.001) and a median door-to-angiogram time of 34 hours were observed.
Conclusion: The high OMI prevalence underscores the need for revised diagnostic and management strategies. Further multi-centre research is needed to validate findings and evaluate whether early OMI identification improves outcomes.