Right Ventricular Infarction

Suspect and look for right ventricular infarction in all patients with inferior STEMI

Diagnostic criteria

In patients with inferior STEMI, right ventricular infarction is suggested by:

  • ST elevation in V1
  • ST elevation in V1 and ST depression in V2 (highly specific for RV infarction)
  • Isoelectric ST segment in V1 with marked ST depression in V2
  • ST elevation in III > II

Diagnosis is confirmed by the presence of ST elevation in the right-sided leads (V3R-V6R)

  • V1 is the only standard ECG lead that looks directly at the right ventricle
  • Lead III is more rightward facing than lead II and hence more sensitive to the injury current produced by the right ventricle

Clinical Significance of RV Infarction
  • RV infarction complicates up to 40% of inferior STEMIs (isolated RV infarction is extremely uncommon)
  • These patients 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!


Right-sided leads

There are several 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 mid-clavicular line
  • ST elevation in V4R has a sensitivity of 88%, specificity of 78% and diagnostic accuracy of 83% in the diagnosis of RV MI
Right sided 12 lead ECG lead placement
Full right sided 12-lead ECG
V4R ECG lead placement
V4R in 12-lead ECG

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 ECG

Example 1a
ECG Right ventricular infarction 1

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:

ECG Right ventricular infarction 1b V4R
  • There is ST elevation in V4R consistent with RV infarction

Example 2
ECG Right ventricular infarction 2

Another example of right ventricular infarction in the context of inferior STEMI:

  • ST elevation in lead III > lead II
  • Isoelectric ST segment in V1 with marked ST depression in V2
  • There is ST elevation in V4R.

Example 3
ECG Right ventricular infarction 3 Right sided leads

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

Example 4a

Try this one yourself…

Inferior-STEMI-RV
Reveal Interpretation
  • Inferior STEMI with STE in III > II
  • Reciprocal ST depression in aVL and I
  • Isoelectric ST segment in V1 with ST depression in V2-3
  • These findings are consistent with inferior STEMI due to RCA occlusion, plus likely associated RV infarction.

Example 4b

Same patient, 9 minutes later…

RV-MI-confirmed
Reveal Interpretation
  • Rapid evolution of inferior STEMI with dynamic increase in height of ST segments – this patient needs urgent PCI!
  • V4R shows loss of R-wave height, significant ST elevation (> 0.5mm; ST segment > R wave) and hyperacute T wave (very large T wave given amplitude of QRS complex) – this confirms the diagnosis of RV MI
  • Development of Wenckebach 2nd degree AV block indicates AV nodal ischaemia or a Bezold-Jarisch reflex (increased vagal tone often seen with inferior MI)


References

  • 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]

Advanced Reading

Online

Textbooks


LITFL Further Reading

ECG LIBRARY 700

ECG LIBRARY

Electrocardiogram

Emergency Physician in Prehospital and Retrieval Medicine in Sydney, Australia. He has a passion for ECG interpretation and medical education | ECG Library |

MBBS (UWA) CCPU Emergency Medicine Advanced Trainee based in Melbourne, Australia. Co-author of the LITFL ECG Library. Likes Ultrasound, Echo, ECGs, and anything and everything with caffeine. Part of the 2021 ANZCEN Clinician Educator Incubator Programme | @rob_buttner | ECG Library |

5 Comments

  1. really excellent explanation, thanks

  2. Alexis Christofi
    Alexis Christofi

    great great great explanation…thank you guys

  3. Richard R Robbins
    Richard R Robbins

    This is great. I need resources like this since I have been retired for several years and planning on taking a job again in the pre hospital field.

  4. If they’re hypertensive with a inferior omi with confirmed RVI, can be give nitrates or not? I know we need watch as they’re preload sensitive, but what would be best for long pt contact times?

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