NHA EKG TECHNICIAN
CERTIFICATION (CET) HIGH-LEVEL
PRACTICE EXAM
1. Where is the primary pacemaker of the heart located?
A. In the upper part of the interventricular septum
B. In the inferior portion of the interatrial septum
C. In the wall of the right atrium near the opening of the superior vena cava
D. In the subendocardial layer of the ventricular walls
Answer: C
Conceptual Explanation: The Sinoatrial (SA) node is the heart’s natural pacemaker and is
located in the right atrium near the superior vena cava.
2. A technician notes a PR interval of 0.24 seconds. Which of the following is the most likely
interpretation?
A. Normal Sinus Rhythm
B. First-degree Atrioventricular Block
C. Second-degree Type I Block
D. Junctional Rhythm
,Answer: B
Conceptual Explanation: A PR interval greater than 0.20 seconds (five small boxes) is
indicative of a First-degree AV Block.
3. Which lead is placed at the fifth intercostal space, at the left midaxillary line?
A. V4
B. V6
C. V5
D. V3
Answer: B
Conceptual Explanation: Lead V6 is placed at the horizontal level of V4 at the midaxillary
line.
4. On a standard EKG, the paper speed is set to 25 mm/sec. What does one small square
represent in terms of time?
A. 0.1 seconds
B. 0.2 seconds
C. 0.01 seconds
D. 0.04 seconds
Answer: D
, Conceptual Explanation: At a standard speed of 25 mm/sec, one small 1mm box
represents 0.04 seconds.
5. Which electrode is considered the ground electrode in a standard 12-lead EKG?
A. Left Arm
B. Left Leg
C. Right Arm
D. Right Leg
Answer: D
Conceptual Explanation: The Right Leg (RL) electrode serves as the ground to reduce
electrical interference or artifact.
6. An EKG shows a saw-tooth pattern of F-waves with a regular ventricular rate. This rhythm
is most likely:
A. Atrial Fibrillation
B. Ventricular Tachycardia
C. Atrial Flutter
D. Sinus Tachycardia
Answer: C
Conceptual Explanation: Atrial Flutter is characterized by rapid, regular ‘saw-tooth’ atrial
waves (F-waves).
CERTIFICATION (CET) HIGH-LEVEL
PRACTICE EXAM
1. Where is the primary pacemaker of the heart located?
A. In the upper part of the interventricular septum
B. In the inferior portion of the interatrial septum
C. In the wall of the right atrium near the opening of the superior vena cava
D. In the subendocardial layer of the ventricular walls
Answer: C
Conceptual Explanation: The Sinoatrial (SA) node is the heart’s natural pacemaker and is
located in the right atrium near the superior vena cava.
2. A technician notes a PR interval of 0.24 seconds. Which of the following is the most likely
interpretation?
A. Normal Sinus Rhythm
B. First-degree Atrioventricular Block
C. Second-degree Type I Block
D. Junctional Rhythm
,Answer: B
Conceptual Explanation: A PR interval greater than 0.20 seconds (five small boxes) is
indicative of a First-degree AV Block.
3. Which lead is placed at the fifth intercostal space, at the left midaxillary line?
A. V4
B. V6
C. V5
D. V3
Answer: B
Conceptual Explanation: Lead V6 is placed at the horizontal level of V4 at the midaxillary
line.
4. On a standard EKG, the paper speed is set to 25 mm/sec. What does one small square
represent in terms of time?
A. 0.1 seconds
B. 0.2 seconds
C. 0.01 seconds
D. 0.04 seconds
Answer: D
, Conceptual Explanation: At a standard speed of 25 mm/sec, one small 1mm box
represents 0.04 seconds.
5. Which electrode is considered the ground electrode in a standard 12-lead EKG?
A. Left Arm
B. Left Leg
C. Right Arm
D. Right Leg
Answer: D
Conceptual Explanation: The Right Leg (RL) electrode serves as the ground to reduce
electrical interference or artifact.
6. An EKG shows a saw-tooth pattern of F-waves with a regular ventricular rate. This rhythm
is most likely:
A. Atrial Fibrillation
B. Ventricular Tachycardia
C. Atrial Flutter
D. Sinus Tachycardia
Answer: C
Conceptual Explanation: Atrial Flutter is characterized by rapid, regular ‘saw-tooth’ atrial
waves (F-waves).
