A new and modified northern occlusion myocardial infarction pattern

BACKGROUND: Currently, it is challenging to identify atypical occlusive myocardial infarction (OMI) in clinical practice. OBJECTIVE: To analyze and discuss the potential electrocardiogram (ECG) manifestations of the recently proposed Northern occlusive myocardial infarction (Northern OMI) in the context of acute coronary syndrome (ACS), as well as the associated vessel types. METHODS: We conducted a retrospective analysis of clinical data from patients who exhibited ST-segment elevation (STE) in leads aVR and aVL on electrocardiography over the past 18 months. Patients with typical ECG manifestations associated with ST-segment elevation occlusive myocardial infarction (STE-OMI) were excluded. All included patients underwent emergent coronary angiography to confirm the presence of coronary artery lesions. RESULTS: A total of 9 patients with STE in leads aVR and aVL were included in the study. Their ECG findings did not fully meet the current diagnostic criteria for Northern OMI. Among these patients, 8 were diagnosed with OMI, with culprit vessels involving both single-vessel and multivessel lesions, 7 received timely coronary intervention treatment and 1 declined coronary intervention owing to advanced age and comorbidities, opting instead for conservative treatment. The remaining case was attributed to acute brainstem hemorrhage, timely therapeutic intervention was administered. CONCLUSION: The current diagnostic model for Northern OMI may have limitations. This study proposes an modified diagnostic criterion characterized by ST-segment elevation in leads aVR and aVL, accompanied by reciprocal ST-segment depression (STD) in at least leads II, III, and aVF.