Clinical Report: Acute Occlusion of the Left Main Coronary Artery

Overview

This case study presents a 69-year-old woman with acute occlusion of the left main coronary artery (LMCA) identified through the South African flag sign (SAFS) on ECG. Successful percutaneous coronary intervention (PCI) restored blood flow.

Background

The South African flag sign (SAFS) on ECG is typically associated with high lateral wall myocardial infarction due to first diagonal branch occlusion. Its occurrence in LMCA occlusion is rare.

Data Highlights

No numerical data or trial data provided in the article.

Key Findings

• A 69-year-old woman presented with chest pain and SAFS on ECG.
• Initial diagnosis suggested high lateral myocardial infarction due to first diagonal branch occlusion.
• Coronary angiography revealed complete occlusion of the LMCA with TIMI flow grade 0.
• Successful PCI restored TIMI flow grade III.
• Follow-up at one and six months showed no adverse cardiac events.

Clinical Implications

Clinicians should consider the possibility of severe coronary artery pathology when encountering SAFS on ECG. Urgent coronary angiography is essential for accurate diagnosis in cases of suspected acute coronary occlusion.

Conclusion

This case emphasizes the importance of integrating ECG findings with clinical context.

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