Patients with circumflex occlusions miss out on reperfusion

PURPOSE OF REVIEW: To review the diagnosis of circumflex occlusion, and why it is important for patient care. RECENT FINDINGS: The ECG is an essential tool for identifying patients who might benefit from reperfusion therapy with ST segment elevation being a requirement. However, circumflex occlusions are often not recognized. Patients with circumflex acute coronary syndromes (ACSs) often present without ST segment elevation even when there is a total occlusion causing a full-thickness inferobasal (previously called posterior) infarction. Recent registries and trials show overrepresentation of circumflex occlusions in non-ST elevation ACS and underrepresentation in ST elevation myocardial infarction populations. This is because usually only the 12-lead ECG has been recorded.Leads V7-V9 should be recorded if there is a clinical suspicion of circumflex territory involvement, such as ST depression in leads V1-V3, or presentation with a normal 12-lead ECG with hemodynamic compromise. SUMMARY: If ST elevation in the circumflex territory is not recognized, patients may be treated inappropriately as having a non-ST elevation ACS without having primary percutaneous coronary intervention or receiving early administration of fibrinolytic therapy. There is a large opportunity for saving thousands of lives worldwide if circumflex occlusions are recognized and treated appropriately.