Morphology of right ventricular paced beats in posterior myocardial infarction.

Premature ventricular beats or paced beats can unmask new or old myocardial infarction when sinus beats fail to exhibit the typical infarct pattern. Knowledge of their morphology is vital, since they may be the earliest or even the only evidence of a myocardial infarction in certain cases. Morphology of premature ventricular beats or paced beats in anterior, anteroseptal, and inferior infarct has been described but not in the setting of a posterior infarct. We describe the morphology of right ventricular paced beats in a patient with posterior infarct and discuss its significance.