Pacemakers & Cardiac Devices Flashcards
7 cards from real EKG certification Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pacemakers & Cardiac Devices flashcards as text
What is 'failure to sense' (undersensing) in a pacemaker?
Answer: The pacemaker fails to recognize the patient's intrinsic heartbeats
Undersensing (failure to sense) occurs when the pacemaker does not detect native cardiac depolarizations and fires inappropriately, potentially on top of native beats.
What is 'oversensing' in a pacemaker?
Answer: The pacemaker inappropriately detects non-cardiac signals and inhibits pacing
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.
What is pacemaker syndrome?
Answer: Symptoms caused by loss of AV synchrony during ventricular-only pacing
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.
In a dual-chamber (DDD) pacemaker, what does the letter 'D' in the THIRD position indicate?
Answer: Both inhibition and triggering responses can occur
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.
What does a rate-responsive (VVIR or DDDR) pacemaker feature do?
Answer: It increases the pacing rate in response to physical activity or metabolic demand
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.
What is the primary purpose of an Implantable Cardioverter-Defibrillator (ICD)?
Answer: To detect and terminate life-threatening ventricular arrhythmias with a shock
An ICD continuously monitors cardiac rhythm and delivers an internal defibrillation shock to terminate ventricular fibrillation or ventricular tachycardia, preventing sudden cardiac death.
On an EKG, what does the absence of pacemaker spikes in a patient with a permanent pacemaker and very slow heart rate most likely indicate?
Answer: Battery depletion or component failure of the pacemaker
Absence of pacemaker spikes in a dependent patient with bradycardia strongly suggests pacemaker failure due to battery depletion, component malfunction, or complete lead fracture.