Complete Practice Questions & Rationales 2026 -
2027
Question 1
Which arrhythmia is characterized by an irregularly irregular rhythm with no
P waves and a ventricular rate that may be controlled or rapid?
A. Atrial flutter
B. Atrial fibrillation
C. Sinus arrhythmia
D. Wandering pacemaker
*Correct Answer: B. Atrial fibrillation. *
Rationale: Atrial fibrillation is characterized by an irregularly irregular
rhythm with no discernible P waves. The ventricular response is often rapid if
uncontrolled, but may be controlled with medications.
Question 2
A patient's EKG shows a regular rhythm with a heart rate of 40 bpm, narrow
QRS complexes, and inverted P waves before each QRS. This is most
consistent with:
A. Junctional rhythm
B. Sinus bradycardia
C. Atrial fibrillation
D. Ventricular escape rhythm
*Correct Answer: A. Junctional rhythm. *
,Rationale: A junctional rhythm originates from the AV junction, typically at
40-60 bpm. It is characterized by inverted or absent P waves (or P waves after
the QRS) and narrow QRS complexes.
Question 3
A patient's EKG shows a run of three or more premature ventricular
contractions (PVCs) at a rate of 150 bpm. This is best described as:
A. Ventricular fibrillation
B. Ventricular tachycardia
C. Supraventricular tachycardia
D. Atrial flutter
*Correct Answer: B. Ventricular tachycardia. *
Rationale: Ventricular tachycardia is defined as three or more consecutive
PVCs at a rate >100 bpm. It is characterized by wide QRS complexes (>0.12
seconds) and no P waves.
Question 4
Which lead placement error would cause a negative P wave in lead II?
A. Right arm and left arm electrodes reversed
B. Left arm and left leg electrodes reversed
C. Right arm and right leg electrodes reversed
D. Chest leads placed too high
*Correct Answer: B. Left arm and left leg electrodes reversed. *
Rationale: Reversing the left arm and left leg electrodes will result in a
negative P wave in lead II because lead II normally records the potential
,difference between the left leg and right arm. This reversal alters the
electrical axis.
Question 5
What is the appropriate action if an EKG technician observes a patient's
tracing showing a wandering baseline?
A. Increase the paper speed
B. Check electrode adhesion and skin preparation
C. Adjust the gain
D. Replace the lead wires
*Correct Answer: B. Check electrode adhesion and skin preparation. *
Rationale: A wandering baseline is most often caused by poor electrode
contact due to inadequate skin preparation or loose electrodes. The
technician should check electrode adhesion and skin preparation.
Question 6
A patient's EKG tracing shows 60-cycle (AC) interference. Which of the
following is the most likely cause?
A. Patient movement
B. Electrical interference from nearby equipment
C. Poor skin preparation
D. Worn lead wires
*Correct Answer: B. Electrical interference from nearby equipment. *
Rationale: 60-cycle interference appears as a fine, uniform oscillation on the
tracing and is caused by electrical interference from nearby equipment, such
as IV pumps, monitors, or fluorescent lights.
, Question 7
A patient's EKG tracing shows muscle tremor artifact. Which action should
the technician take?
A. Increase the gain
B. Ask the patient to relax and remain still
C. Replace the electrodes
D. Use a different lead
*Correct Answer: B. Ask the patient to relax and remain still. *
Rationale: Muscle tremor artifact is caused by patient movement, muscle
tension, or shivering. The technician should ask the patient to relax and
remain still. A warm blanket may help if the patient is shivering.
Question 8
Which of the following is an appropriate action for an EKG technician to
take when a patient reports chest pain during an EKG?
A. Continue the EKG
B. Stop the procedure, notify the provider, and assess the patient
C. Administer aspirin
D. Complete the EKG quickly
*Correct Answer: B. Stop the procedure, notify the provider, and assess
the patient. *
Rationale: Chest pain during an EKG may indicate a cardiac event and
requires immediate medical attention. The technician should stop the
procedure, notify the provider, and assess the patient.