McKenna's Pharmacology for Nursing, 2e

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P A R T 8  Drugs acting on the cardiovascular system

B

A

PVC

Premature ventricular contraction (PVC).

C

D

Heart block with PVCs.

FIGURE 45.4  Premature ventricular contractions (PVCs) or ventricular premature beats (VPBs). Rhythm: irregular. Rate: variable; only interrupts the cycle of the ectopic, ventricular contraction. P–R interval: normal in sinus beats, not measurable in PVCs. QRS: wide, bizarre, greater than 0.12 seconds.