Rhythm InterpretationQuestion 27 of 100
A strip shows a sharp, narrow vertical spike immediately before each wide QRS complex at a regular rate of 70. What does this indicate?
a.A ventricular paced rhythm
b.Sixty-cycle AC interference
c.A premature ventricular contraction pattern
d.Somatic tremor artifact
Explanation
A pacemaker spike is a thin vertical line marking the electrical impulse delivered by the device; a spike followed by a wide QRS indicates ventricular capture. AC interference appears as a uniform fuzzy band across the whole tracing rather than a single spike per beat. Premature ventricular contractions occur early and irregularly without spikes, and somatic tremor causes erratic jagged baseline movement.
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Related questions on this topic
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