EKG certification Certification Pacemakers & Cardiac Devices 2

Question 1

What is 'failure to sense' (undersensing) in a pacemaker?

Accepted Answer

The pacemaker fails to recognize the patient's intrinsic heartbeats

Answer

Undersensing (failure to sense) occurs when the pacemaker does not detect native cardiac depolarizations and fires inappropriately, potentially on top of native beats.

Question 2

What is 'oversensing' in a pacemaker?

Accepted Answer

The pacemaker inappropriately detects non-cardiac signals and inhibits pacing

Answer

Oversensing occurs when the pacemaker misinterprets non-cardiac signals (such as muscle artifact or T waves) as intrinsic cardiac activity and inappropriately inhibits pacing output.

Question 3

What is pacemaker syndrome?

Accepted Answer

Symptoms caused by loss of AV synchrony during ventricular-only pacing

Answer

Pacemaker syndrome occurs when VVI pacing causes loss of AV synchrony, leading to symptoms like hypotension, dizziness, fatigue, and pulsations in the neck due to atrial contraction against closed AV valves.

Question 4

In a dual-chamber (DDD) pacemaker, what does the letter 'D' in the THIRD position indicate?

Accepted Answer

Both inhibition and triggering responses can occur

Answer

In the NBG code, 'D' in the third position (response to sensing) means the pacemaker has a dual response: it can be inhibited by sensed events in one chamber and triggered in another.

Question 5

What does a rate-responsive (VVIR or DDDR) pacemaker feature do?

Accepted Answer

It increases the pacing rate in response to physical activity or metabolic demand

Answer

The rate-responsive feature (indicated by 'R' in the fourth position of the pacemaker code) uses sensors to detect physical activity or physiological changes and increases the pacing rate to match the patient's metabolic needs.

EKG certification Practice Test

EKG certification Practice Test

EKG certification Certification Pacemakers & Cardiac Devices 2