EKG certification Certification Pacemakers & Cardiac Devices 1 — Questions and Answers
Question 1: What EKG finding is the hallmark of pacemaker activity?
- A tall, narrow P wave
- A pacemaker spike (pacer artifact) preceding the paced beat (Correct answer)
- A widened QRS complex without a preceding spike
- A prolonged PR interval
Correct answer: A pacemaker spike (pacer artifact) preceding the paced beat
A pacemaker spike is a sharp vertical deflection on the EKG that immediately precedes the paced P wave or QRS complex, confirming pacemaker activity.
Question 2: In the NBG pacemaker code, what does the FIRST letter represent?
- The response to sensing
- The chamber sensed
- The chamber paced (Correct answer)
- The programmability of the device
Correct answer: The chamber paced
In the NBG (North American Society of Pacing and Electrophysiology/British Pacing Group) code, the first letter always indicates the chamber being paced (A=Atrium, V=Ventricle, D=Dual).
Question 3: What is 'failure to capture' in a pacemaker?
- The pacemaker fails to detect native cardiac activity
- A pacemaker spike is present but no myocardial depolarization follows (Correct answer)
- The pacemaker fires too rapidly
- The pacemaker fails to deliver any output
Correct answer: A pacemaker spike is present but no myocardial depolarization follows
Failure to capture occurs when a pacemaker spike is visible on the EKG but is not followed by a P wave or QRS complex, meaning the impulse did not depolarize the myocardium.
Question 4: Which EKG morphology is characteristically seen with right ventricular pacing?
- Narrow QRS complex, left axis deviation
- Wide QRS complex with left bundle branch block (LBBB) morphology (Correct answer)
- Wide QRS complex with right bundle branch block (RBBBB) morphology
- Normal QRS complex with ST elevation
Correct answer: Wide QRS complex with left bundle branch block (LBBB) morphology
Right ventricular pacing produces a wide QRS with LBBB morphology because the right ventricle is depolarized first via the pacing lead, causing abnormal left-to-right ventricular activation.
Question 5: What does a VVI pacemaker mode mean?
- Atrium paced, ventricle sensed, inhibited response
- Ventricle paced, ventricle sensed, inhibited response (Correct answer)
- Both chambers paced and sensed, inhibited response
- Ventricle paced, no sensing, asynchronous pacing
Correct answer: Ventricle paced, ventricle sensed, inhibited response
VVI means the ventricle is paced (first V), the ventricle is sensed (second V), and the pacemaker is inhibited (I) when it senses native ventricular activity.
Question 6: What is the lower rate limit (LRL) of a pacemaker?
- The fastest rate at which the pacemaker will pace
- The minimum heart rate below which the pacemaker will fire (Correct answer)
- The maximum tracking rate for sensed atrial events
- The rate at which the pacemaker switches modes
Correct answer: The minimum heart rate below which the pacemaker will fire
The lower rate limit (LRL) is the programmed minimum rate; if the patient's intrinsic rate falls below this value, the pacemaker will fire to maintain adequate cardiac output.
Question 7: Which condition is a primary indication for implanting a permanent pacemaker?
- Atrial fibrillation with rapid ventricular response
- Symptomatic third-degree (complete) heart block (Correct answer)
- Frequent premature ventricular contractions (PVCs)
- Wolff-Parkinson-White (WPW) syndrome
Correct answer: Symptomatic third-degree (complete) heart block
Symptomatic third-degree (complete) heart block is a Class I indication for permanent pacemaker implantation because there is no reliable conduction between atria and ventricles.
EKG certification Certification Pacemakers & Cardiac Devices 1
What EKG finding is the hallmark of pacemaker activity?