Pseudofusion

A 60 yo with h/o HTN, DM and ESRD s/p PPP insertion for SSS.

Figure 1

This is AV pacing. The ventricular pacemaker stimulus did not alter the QRS morphology. So, what is seen is a narrow QRS complex. This means the pacer stimulus occurred after the normal depolarization of the ventricles has started. This is called PSEUDOFUSION and the machine functioning normally.

Reference:

Bonnow et al. 2014. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th Edition. PA.Saunders

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