Common Symptoms of Posterior Myocardial Infarction
Posterior myocardial infarction (PMI) commonly presents with nausea, vomiting, diaphoresis (sweating), hypotension, and extreme weakness or fatigue, often with atypical chest pain that may radiate to the back or between the shoulder blades (interscapular region). 1
Clinical Presentation
Posterior myocardial infarction has a unique symptom profile that differs from other types of MI:
Common Symptoms
- Nausea and vomiting (very common)
- Hypotension (often significant)
- Diaphoresis (sweating)
- Extreme weakness or fatigue
- Dyspnea (shortness of breath) as a predominant symptom 1
- Epigastric discomfort (may be mistaken for indigestion)
- Chest discomfort that may be less severe than typical MI 1
- Pain that may radiate to the back, particularly between the shoulder blades 1
Important Clinical Considerations
- PMI often presents with atypical symptoms rather than the classic crushing chest pain 1
- Symptoms may be easily misinterpreted as gastrointestinal issues due to prominent nausea and vomiting
- The European Society of Cardiology notes that PMI can be challenging to diagnose due to these atypical presentations 1
- Autonomic nervous system activation (pallor, sweating) is common in MI patients 2
Special Populations and Atypical Presentations
Certain groups are more likely to present with atypical symptoms:
- Women often experience unusual fatigue, sleep disturbances, indigestion, and anxiety 1
- Elderly patients may present with confusion, generalized weakness, or changes in mental status 1, 3
- Diabetic patients frequently have atypical presentations 1
Diagnostic Challenges
PMI is particularly challenging to diagnose because:
- Standard 12-lead ECG may not directly visualize the posterior wall 1, 4
- ECG changes may be subtle, showing ST depression in leads V1-V3 rather than classic ST elevation 1
- Additional posterior leads (V7-V9) are required for direct visualization of the posterior wall 1, 5
Clinical Pitfalls to Avoid
- Don't dismiss gastrointestinal symptoms (nausea, vomiting, epigastric discomfort) without considering cardiac causes, especially in high-risk patients
- Don't wait for "typical" chest pain before considering PMI diagnosis
- Don't overlook hypotension as a significant clinical sign of PMI
- Don't delay diagnosis - early recognition significantly reduces morbidity and mortality 1
Importance of Prompt Recognition
Delayed diagnosis of PMI can lead to delayed reperfusion therapy, emphasizing the need for early recognition and treatment to reduce morbidity and mortality 1. Any symptoms of a heart attack, especially when they last more than a few minutes or come and go, warrant immediate medical attention by calling emergency services.