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38-year-old male with left arm pain, shortness of breath, and dizziness. BP 105/60.
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ECG interpretation
Inferior STEMI
- Marked ST elevation and hyperacute T waves (HATW) in leads II, III, aVF and I
- Reciprocal ST depression in V1-3 and aVR
- Q waves in leads I, II
- T waves in V4-6 are broadened also resembling HATW
- Borderline first degree AV block
Notably, marked ST depression in V2 > V1 should prompt us to consider right ventricular infarction and have caution with nitrates.
AI interpretation by PMcardio
PMcardio’s AI ECG model identified a STEMI/STEMI equivalent.
The explainability feature offers insights into problematic patterns in the respective leads, providing a clear rationale for the diagnosis.
Further reading
Outcome
Key Finding:
Mid right coronary artery (RCA) occlusion
Findings:
- Left Main Coronary Artery – mild irregularities
- Left Anterior Descending Coronary Artery – mild irregularities
- Left Circumflex Coronary Artery – mild irregularities
- Right Coronary Artery – dominant and occluded mid-vessel
- Left ventriculogram – mild-moderate systolic dysfunction
Plan:
- Proceeded to PCI to RCA.
Clinical Pearls
In inferior OMI, always look closely for features of RV infarction. ST elevation in V1 is a sensitive sign, but this sensitivity drastically decreases in the presence of ST depression in V2.
Examine closely for ST depression in V2 relative to an isoelectric ST segment in V1 which may be suggestive. Diagnosis is confirmed by the presence of ST elevation in right-sided leads (V3R-V6R).
References
Further reading
- Bischof JE, Worrall CI, Smith SW. In inferior myocardial infarction, neither ST elevation in lead V1 nor ST depression in lead I are reliable findings for the diagnosis of right ventricular infarction. J Electrocardiol. 2018 Nov-Dec;51(6):977-980.
- Buttner R, Burns E. Inferior STEMI. LITFL
- Buttner R, Burns E. Right Ventricular Infarction. LITFL
- Nickson C. STEMI Management. LITFL
Online resources
- Wiesbauer F, Kühn P. ECG Mastery: Yellow Belt online course. Understand ECG basics. Medmastery
- Wiesbauer F, Kühn P. ECG Mastery: Blue Belt online course: Become an ECG expert. Medmastery
- Kühn P, Houghton A. ECG Mastery: Black Belt Workshop. Advanced ECG interpretation. Medmastery
- Smith SW. Dr Smith’s ECG blog.
- Rawshani A. Clinical ECG Interpretation ECG Waves
ACTIVATE or WAIT
EKG Interpretation
MBBS FACEM DDU (Emergency) CCPU. Emergency Physician in Melbourne, Australia. Co-Ultrasound Lead for Emergency Medicine at The Alfred Hospital. Special interests in diagnostic and procedural ultrasound, medical education, and ECG interpretation. Editor of the LITFL ECG Library.
Dr. Stephen W. Smith is a faculty physician in the Emergency Medicine Residency at Hennepin County Medical Center (HCMC) in Minneapolis, MN, and Professor of Emergency Medicine at the University of Minnesota. Author of Dr Smith's ECG Blog | Bibliography | X |
Dr. Hana Hybasek Dzurikova, MRCVS, PGCert MEd is a medical educator driving innovation and change in health professions education through technology-enhanced learning.
