Clinical Significance
- Right ventricular infarction complicates up to 40% of inferior STEMIs. Isolated RV infarction is extremely uncommon.
- Patients with RV infarction are very preload sensitive (due to poor RV contractility) and can develop severe hypotension in response to nitrates or other preload-reducing agents.
- Hypotension in right ventricular infarction is treated with fluid loading, and nitrates are contraindicated.
The ECG changes of RV infarction are subtle and easily missed!
How to spot right ventricular infarction
The first step to spotting RV infarction is to suspect it… in all patients with inferior STEMI!
In patients presenting with inferior STEMI, right ventricular infarction is suggested by the presence of:
- ST elevation in V1 - the only standard ECG lead that looks directly at the right ventricle.
- ST elevation in lead III > lead II - because lead III is more “rightward facing” than lead II and hence more sensitive to the injury current produced by the right ventricle.
Other useful tips for spotting right ventricular MI (as described by Amal Mattu and William Brady in ECGs for the Emergency Physician):
- If the magnitude of ST elevation in V1 exceeds the magnitude of ST elevation in V2.
- If the ST segment in V1 is isoelectric and the ST segment in V2 is markedly depressed.
- NB. The combination of ST elevation in V1 and ST depression in V2 is highly specific for right ventricular MI.
Right ventricular infarction is confirmed by the presence of ST elevation in the right-sided leads (V3R-V6R).
Right-sided leads
There are several different approaches to recording a right-sided ECG:
- A complete set of right-sided leads is obtained by placing leads V1-6 in a mirror-image position on the right side of the chest (see diagram, below).
- It may be simpler to leave V1 and V2 in their usual positions and just transfer leads V3-6 to the right side of the chest (i.e. V3R to V6R).
- The most useful lead is V4R, which is obtained by placing the V4 electrode in the 5th right intercostal space in the midclavicular line. ST elevation in V4R has a sensitivity of 88%, specificity of 78% and diagnostic accuracy of 83% in the diagnosis of RV MI.
Reproduced from Morris and Brady, 2002. Click image for link to original reference.
NB. ST elevation in the right-sided leads is a transient phenomenon, lasting less than 10 hours in 50% of patients with RV infarction.
Example ECGs
Example 1a
Inferior STEMI. Right ventricular infarction is suggested by:
- ST elevation in V1
- ST elevation in lead III > lead II
Example 1b
Repeat ECG of the same patient with V4R electrode position:
- There is ST elevation in V4R consistent with RV infarction
Example 2
Another example of right ventricular MI:
- There is an inferior STEMI with ST elevation in lead III > lead II.
- There is subtle ST elevation in V1 with ST depression in V2.
- There is ST elevation in V4R.
Example 3
This ECG shows a full set of right-sided leads (V3R-V6R), with V1 and V2 in their original positions. RV infarction is diagnosed based on the following findings:
- There is an inferior STEMI with ST elevation in lead III > lead II.
- V1 is isoelectric while V2 is significantly depressed.
- There is ST elevation throughout the right-sided leads V3R-V6R.
Related Topics
Author Credits
Further Reading
- ECG BASICS – Waves, Intervals, Segments and Clinical Interpretation
- ECG CLINICAL CASES – Your favourite ECG’s placed in clinical context with a challenging Q&A approach
- ECG and Cardiology Eponymous Syndromes – Cheats guide to eponymous emancipation
- ECG Reference Sites on the WEB – the best of the rest
References
- Mattu A, Brady W. ECGs for the Emergency Physician 1, BMJ Books 2003.
- Mattu A, Brady W. ECGs for the Emergency Physician 2, BMJ Books 2008.
- Morris F, Brady WJ. ABC of clinical electrocardiography: Acute myocardial infarction-Part I. BMJ. 2002; 324: 831-4. [full text]
- Edhouse J, Brady WJ, Morris F. ABC of clinical electrocardiography: Acute myocardial infarction-Part II. BMJ. 2002; 324: 963-6. [full text]
- Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice (6th edition), Saunders 2008.
About Edward Burns
Excellent article, well written.
Thank you. Hope you found it useful! Ed
Hi there, just a note from my tutor
right ventricular infarct as suggested by deep ST depression in lead 1 and avL (>3mm added together), ST elevation of lead 3>lead2….
RV infarct accompanies inf infarct in about 50% of the time….
You could do a right sided ECG to confirm it… most prominent change in vR4…
Ed isn’t the ECG quiz 012 a clear right ventricular infarct?
excellent….beautifully presented….so easily shared….really this site is very much helpful one