CET Holter Monitoring & Ambulatory ECG 2 — Questions and Answers
Question 1: A patient's Holter diary shows chest pain at 2:14 PM. The technician should first look for arrhythmias or ST changes in the recording at what time relative to the diary entry?
- Exactly at 2:14 PM
- 5 minutes before and after 2:14 PM (Correct answer)
- Only after 2:14 PM
- Only before 2:14 PM
Correct answer: 5 minutes before and after 2:14 PM
Reviewing a window around the symptom time (before and after) captures both precipitating arrhythmias and resulting changes.
Question 2: During Holter analysis, a technician notices the patient's heart rate drops to 28 bpm for 6 seconds during sleep. This finding is most consistent with:
- Sinus bradycardia requiring immediate intervention
- Junctional escape rhythm
- Vagally mediated sinus pause, common during sleep (Correct answer)
- Complete heart block
Correct answer: Vagally mediated sinus pause, common during sleep
Brief nocturnal sinus pauses up to 2–3 seconds are a normal vagal phenomenon in athletes and during sleep; isolated pauses without symptoms are usually benign.
Question 3: Which electrode placement error most commonly produces a wandering baseline artifact on a Holter recording?
- Electrodes placed too close together
- Inadequate skin preparation before electrode attachment (Correct answer)
- Patient moving arms excessively
- Recorder battery malfunction
Correct answer: Inadequate skin preparation before electrode attachment
Poor skin prep leaves oils and dead cells that cause high-impedance connections, resulting in wandering baseline artifact.
Question 4: A 48-hour Holter report states 'total QRS complexes analyzed: 87,432 with 2.1% ventricular ectopy.' Approximately how many PVCs does this represent?
- 874
- 1,836 (Correct answer)
- 4,200
- 8,743
Correct answer: 1,836
2.1% of 87,432 ≈ 1,836 PVCs over the 48-hour period.
Question 5: A patient returns a Holter recorder with only 18 hours of data on a prescribed 24-hour study. The BEST next step is to:
- Report the 18-hour data as a complete study
- Note the incomplete recording and schedule a repeat study if clinically indicated (Correct answer)
- Discard the data and reschedule immediately
- Extrapolate findings to 24 hours mathematically
Correct answer: Note the incomplete recording and schedule a repeat study if clinically indicated
The technician should document the abbreviated recording duration and communicate with the ordering physician to determine whether a repeat study is needed.
Question 6: On a Holter tracing, supraventricular tachycardia (SVT) is BEST distinguished from ventricular tachycardia (VT) by:
- Heart rate during tachycardia
- QRS width during tachycardia (Correct answer)
- Duration of the tachycardia episode
- PR interval before tachycardia onset
Correct answer: QRS width during tachycardia
Narrow QRS (<120 ms) during tachycardia strongly suggests SVT, while wide QRS (≥120 ms) suggests VT or SVT with aberrancy.
Question 7: When applying Holter electrodes, the technician should clip chest hair rather than shave it. The primary reason is:
- Shaving causes skin irritation that increases artifact (Correct answer)
- Clipping is faster than shaving
- Shaving is not permitted by hospital policy
- Clipped hair holds electrodes more securely
Correct answer: Shaving causes skin irritation that increases artifact
Shaving can cause micro-abrasions that irritate skin and may increase impedance or discomfort; clipping reduces hair without disrupting the skin barrier.
CET Holter Monitoring & Ambulatory ECG 2
A patient's Holter diary shows chest pain at 2:14 PM.
The technician should first look for arrhythmias or ST changes in the recording at what time relative to the diary entry?