CCT Artifact Recognition and Troubleshooting 3

Question 1

Which ECG leads most commonly show baseline wander due to respiratory movement?

Accepted Answer

Inferior limb leads (II, III, aVF)

Answer

Precordial leads V1–V6

Answer

Right precordial leads (V1, V2) only

Answer

Lead aVR exclusively

Question 2

Artifact that closely mimics atrial fibrillation on an ECG is most commonly caused by:

Accepted Answer

Patient shivering or fine muscle tremor (somatic tremor)

Answer

60 Hz AC interference

Answer

Reversed precordial lead placement

Answer

Low-frequency baseline wander from respiration

Question 3

When a patient cannot remain still during an ECG due to uncontrollable tremors, the technician should:

Accepted Answer

Document the artifact, note the clinical condition, and record the best quality tracing possible

Answer

Proceed without documentation and submit the tracing as normal

Answer

Cancel the ECG and reschedule when the patient is better

Answer

Apply pressure bandages to immobilize the extremities

Question 4

If the right leg (RL/N) electrode becomes detached during recording, what effect would most likely be observed?

Accepted Answer

Significant artifact or loss of signal in all limb leads due to broken ground reference

Answer

Inversion of the P wave in lead II only

Answer

Complete loss of the precordial leads only

Answer

Right bundle branch block pattern in V1-V2

Question 5

A technician notices the QRS complex is predominantly positive in lead aVR on a routine ECG. This finding most likely indicates:

Accepted Answer

Right arm and left arm lead reversal artifact

Answer

Right ventricular hypertrophy

Answer

Anterior myocardial infarction

Answer

Normal variant in elderly patients

Question 6

Which ECG machine filter setting is designed specifically to reduce low-frequency baseline wander?

Accepted Answer

High-pass filter (e.g., 0.5 Hz cutoff)

Answer

Notch filter (60 Hz)

Answer

Low-pass filter (e.g., 40 Hz cutoff)

Answer

Band-reject filter centered at 50 Hz

Question 7

When is it appropriate to activate the ECG machine's built-in artifact filters?

Accepted Answer

Only when proper technique cannot eliminate the artifact, and filter use must be documented

Answer

Routinely on all ECGs to ensure the cleanest possible tracing

Answer

Only for exercise stress testing, never for resting ECGs

Answer

Whenever the cardiologist requests a filtered tracing after the fact