Understanding Anterior STEMI on ECG

Introduction

Acute myocardial infarction (AMI), commonly known as a heart attack, can be classified based on ECG findings. One of the most severe forms is ST-elevation myocardial infarction (STEMI), which features significant ST-segment elevation in certain leads.

Anterior STEMI occurs when there is occlusion of the left anterior descending (LAD) artery. This is a critical condition requiring urgent treatment.

ECG Findings in Anterior STEMI

1. ST-segment Elevation:

• Present in V1-V4 leads (anterior leads).
• The higher the elevation, the more severe the infarction.

2. Reciprocal ST-segment Depression:

• Often seen in the inferior leads (II, III, aVF).
• Indicates a mirror effect of injury.

3. Q Waves Formation:

• These may appear later in the course, suggesting completed infarction.
• Indicates irreversible myocardial damage.

4. Hyperacute T Waves:

• Early sign of infarction before ST elevation.
• Tall, broad T waves in V1-V3 may suggest early STEMI development.

Pathophysiology of Anterior STEMI

• The LAD artery supplies the anterior wall, interventricular septum, and parts of the apex.
• If blocked, significant myocardial damage can occur, leading to heart failure, arrhythmias, or even cardiogenic shock.

Treatment Approach

1. Immediate Reperfusion: - Primary PCI (Percutaneous Coronary Intervention): First-line treatment if available within 90 minutes. - Thrombolysis (if PCI is unavailable): Administer fibrinolytic therapy within 30 minutes.

2. Medical Management: - Aspirin + P2Y12 inhibitor (Clopidogrel/Ticagrelor/Prasugrel) → Prevents clot progression. - Anticoagulation (Heparin or Enoxaparin) → Prevents further thrombus formation. - Beta-blockers (if no contraindications) → Reduces myocardial oxygen demand. - ACE Inhibitors → Reduces risk of heart failure long-term. - Statins → Reduces cholesterol to prevent future events.

Prognosis

The earlier treatment is initiated, the better the prognosis. If left untreated, anterior STEMI can lead to: - Heart failure - Ventricular arrhythmias - Death

Conclusion

Recognizing ECG changes in anterior STEMI is critical for early intervention and saving heart muscle. Medical professionals must act quickly to ensure the best possible outcome.

Source recommendations

1. American Heart Association Guidelines for the Management of ST-Elevation Myocardial Infarction

1. https://professional.heart.org/en/science-news/2021-acc-aha-scai-guideline-for-coronary-artery-revascularization
2. https://www.ahajournals.org/doi/10.1161/cir.0b013e3182742cf6
3. https://pubmed.ncbi.nlm.nih.gov/23256914/
4. https://www.ahajournals.org/doi/10.1161/01.cir.0000134791.68010.fa
5. https://www.sciencedirect.com/science/article/pii/S073510972106157X

2. European Society of Cardiology Guidelines for the Management of Acute Coronary Syndromes

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Acute-Coronary-Syndromes-ACS-Guidelines
2. https://academic.oup.com/eurheartj/article/44/38/3720/7243210
3. https://pubmed.ncbi.nlm.nih.gov/37622654/
4. https://academic.oup.com/eurheartj/article/42/14/1289/5898842
5. https://pubmed.ncbi.nlm.nih.gov/21873419/