From the Guidelines
Posterior STEMI should be identified using leads V7, V8, and V9, with a threshold of ST-segment elevation of ≥0.05 mV in these leads, as recommended by the most recent guidelines 1. To diagnose posterior STEMI, it is essential to use additional posterior chest wall leads, specifically V7, V8, and V9, which provide direct visualization of the posterior wall of the left ventricle. The correct placement of these leads is crucial, with V7 positioned at the posterior axillary line at the same level as V6, V8 at the tip of the left scapula, and V9 at the left paraspinal region. When interpreting the ECG, reciprocal changes can be seen in the anterior leads (V1-V3) as ST-segment depression and tall, upright R waves. The use of these additional leads is particularly important in patients presenting with symptoms suggestive of acute coronary syndrome but with ST depression in V1-V3 rather than clear ST elevation in standard leads, as posterior STEMIs are often missed due to the lack of posterior leads in standard 12-lead ECGs 1. Prompt recognition of posterior STEMI is critical, as it typically involves the circumflex artery and requires the same urgent reperfusion therapy as other STEMIs, with the goal of minimizing the time from symptom onset to initiation of reperfusion therapy, as emphasized in the guidelines 1. Key points to consider in the diagnosis and management of posterior STEMI include:
- The use of additional posterior chest wall leads (V7-V9) to detect ST elevation consistent with infero-basal myocardial infarction
- A threshold of ST-segment elevation of ≥0.05 mV in leads V7-V9 for the diagnosis of posterior STEMI
- The importance of prompt recognition and urgent reperfusion therapy in patients with posterior STEMI
- The need to consider posterior STEMI in patients with symptoms suggestive of acute coronary syndrome but with ST depression in V1-V3 rather than clear ST elevation in standard leads.
From the Research
Posterior STEMI Leads
- The provided studies do not directly discuss posterior STEMI leads, but rather focus on the treatment and management of ST-elevation myocardial infarction (STEMI) in general 2, 3, 4, 5, 6.
- STEMI is a serious condition that requires prompt diagnosis and treatment, with primary percutaneous coronary intervention (PCI) being the preferred reperfusion strategy 2, 3, 4.
- Antithrombotic therapy, including antiplatelet and anticoagulant agents, plays a crucial role in optimizing clinical outcomes for patients with STEMI undergoing primary PCI 6.
- The use of dual antiplatelet therapy with aspirin and an oral P2Y12-receptor inhibitor, such as prasugrel or ticagrelor, is recommended for the acute and long-term treatment of patients with STEMI undergoing primary PCI 6.
- There is no specific information available on posterior STEMI leads in the provided studies, suggesting that further research may be needed to address this topic.