Diagnostic criteria

  On right-sided ECG (the chest leads are symmetrically placed on right chest) C4R, C5R and/or C6R show

      ST segment elevation due to right ventricular myocardial infarction.

  Right ventricular infarction generally developes during acute inferior myocardial infarction

      since the coronary artery to right ventricle usually originates from right coronary artery (RCA).

ECG 1a.
Acute inferior myocardial infarction and accompanying right ventricular infarction .
This ECG was recorded after symmetrically placing the precordial leads on the right chest.

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ECG 1b. The same patient, but the chest electrodes are placed on left chest.

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ECG 2. The above ECG is from a 61 years-old man who is experiencing
acute inferior wall myocardial infarction
While recording the above ECG, his extremity electrodes were connected normally.
However, his chest electrodes were placed symmetrically on his right chest.
With this type of electrode placement, the ST segment elevation in V5 and V6 denotes
right ventricular myocardial infarction.
Since the ECG machine is not aware of this new electrode placement, it perceives the "loss of R progression in chest leads"
as abnormal and comments as "anterior myocardial infarction".
It is also interesting to note that the ECG machine cannot perceive the ST segment elevation in inferior leads.
This results in failure to diagnose the acute inferior wall myocardial infarction.
The rhythm in the above ECG is nodal since no atrial activity (P wave) is seen.

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