A standard 12-lead EKG can be very telling for patients with chest pain or shortness of breath. A right ventricular (RV) and posterior wall infarct, however, can present very subtly. You can obtain special right-sided (V1R-V6R) and posterior leads (V7-V9), if you are concerned.
What are the indications for obtaining right-sided and posterior EKG leads?
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Addendum 3/11/11:
Right sided EKG leads (V1R-V6R) are positioned in a mirror image fashion from the standard 12-lead precordial leads.
Posterior EKG leads (V7-V9) are applied by moving V4-V6 in the posterior positions.