Pacemaker Monitoring and Function Flashcards
7 cards from real CMT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pacemaker Monitoring and Function flashcards as text
A cardiac monitor technician observes that the pacemaker is not firing even though the patient's heart rate has dropped below the programmed lower rate limit. This is most consistent with:
Answer: Failure to pace (oversensing)
Oversensing causes the pacemaker to incorrectly detect non-cardiac signals as native beats, inappropriately inhibiting pacing output.
A pacemaker rhythm strip shows pacemaker spikes occurring in competition with the patient's own intrinsic beats. This pattern suggests:
Answer: Failure to sense (undersensing)
Undersensing occurs when the pacemaker fails to detect the patient's own intrinsic electrical activity, causing it to fire inappropriately.
What is pacemaker-mediated tachycardia (PMT)?
Answer: A reentrant tachycardia in dual-chamber pacemakers triggered by retrograde P waves
PMT is a reentrant loop in dual-chamber pacemakers where retrograde atrial conduction from a ventricular beat is sensed, triggering continuous ventricular pacing.
Which finding on a rhythm strip would MOST likely indicate pacemaker battery depletion?
Answer: Pacing rate drops or converts to backup (EOL) rate
As pacemaker battery approaches end-of-life (EOL), the pacing rate typically drops to a manufacturer-designated elective replacement indicator (ERI) rate.
In a dual-chamber pacemaker, what does the programmed AV delay (AV interval) simulate?
Answer: The normal PR interval seen in sinus rhythm
The programmed AV delay mimics the natural PR interval, allowing appropriate time for atrial emptying before ventricular contraction to preserve AV synchrony.
What does the term 'lower rate limit' refer to in pacemaker programming?
Answer: The slowest rate at which the pacemaker will allow the heart to fall before pacing
The lower rate limit (LRL) is the programmed rate below which the pacemaker will fire to prevent bradycardia.
What is the primary purpose of a rate-responsive (DDDR or VVIR) pacemaker?
Answer: To automatically increase pacing rate in response to physical activity
Rate-responsive pacemakers use sensors (e.g., accelerometer or minute ventilation) to increase pacing rate during physical activity to match metabolic demand.