700
P A R T 8
Drugs acting on the cardiovascular system
PVC
Premature ventricular contraction (PVC).
Heart block with PVCs.
A
B
C
D
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.
