AMCA EKG PRACTICE TEST 2025/2026 Updated
Questions with Correct Answers & Detailed
Rationales COMPLETE Q&A WITH VERIFIED
ANSWERS AND DETAILED RATIONALES |
OBJECTIVE ASSESSMENT PREP | A+ GRADED
Core Domains Covered:
• Cardiac Anatomy and Physiology
• Cardiac Conduction System
• EKG Waveforms and Intervals
• EKG Lead Placement and Acquisition
• Rhythm Interpretation
• Arrhythmia Identification
• Myocardial Infarction Recognition
• Axis Deviation and Hypertrophy
• Artifact Recognition
• EKG Equipment and Safety
• Clinical Application of EKG
QUESTION 1
Which chamber of the heart receives deoxygenated blood from the superior and
inferior vena cava?
A. Left atrium
B. Right atrium
,C. Left ventricle
D. Right ventricle
Correct Answer: B. Right atrium
RATIONALE: The right atrium receives deoxygenated systemic blood from the
superior vena cava (SVC) and inferior vena cava (IVC). The left atrium receives
oxygenated blood from the lungs via the pulmonary veins. Ventricles are the lower
chambers of the heart responsible for pumping blood out of the heart.
QUESTION 2
The pacemaker cells of the heart are located primarily in which structure?
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Sinoatrial (SA) node
D. Bundle of His
Correct Answer: C. Sinoatrial (SA) node
RATIONALE: The SA node, located in the right atrium, is the primary
pacemaker of the heart, generating electrical impulses at a rate of 60-100 beats per
minute. The AV node is a secondary pacemaker with an intrinsic rate of 40-60
bpm. Purkinje fibers have an intrinsic rate of 20-40 bpm.
QUESTION 3
What is the normal intrinsic firing rate of the sinoatrial (SA) node?
A. 20-40 beats per minute
B. 40-60 beats per minute
C. 60-100 beats per minute
D. 100-160 beats per minute
Correct Answer: C. 60-100 beats per minute
RATIONALE: The SA node normally fires at 60-100 beats per minute,
establishing the normal sinus rhythm. The AV node has an intrinsic rate of 40-60
,bpm, and the Purkinje fibers have an intrinsic rate of 20-40 bpm. Rates above 100
bpm indicate tachycardia.
QUESTION 4
Which layer of the heart is responsible for the contractile function?
A. Epicardium
B. Endocardium
C. Myocardium
D. Pericardium
Correct Answer: C. Myocardium
RATIONALE: The myocardium is the middle layer of the heart wall and is
composed of cardiac muscle cells responsible for contraction. The epicardium is
the outer layer. The endocardium is the inner lining. The pericardium is the fibrous
sac surrounding the heart.
QUESTION 5
The atrioventricular (AV) node is located in which area of the heart?
A. Right atrium near the SA node
B. Inferior portion of the interatrial septum
C. Ventricular septum
D. Left ventricular wall
Correct Answer: B. Inferior portion of the interatrial septum
RATIONALE: The AV node is located in the inferior portion of the interatrial
septum near the tricuspid valve. It receives impulses from the SA node and delays
them briefly before transmitting to the ventricles, allowing for atrial contraction
before ventricular contraction.
QUESTION 6
What is the primary function of the Purkinje fibers?
, A. Initiate cardiac impulses
B. Delay conduction to the ventricles
C. Rapidly conduct impulses throughout the ventricles
D. Supply blood to the heart muscle
Correct Answer: C. Rapidly conduct impulses throughout the ventricles
RATIONALE: Purkinje fibers are specialized conducting cells that rapidly
transmit electrical impulses from the bundle branches throughout the ventricular
myocardium, ensuring coordinated ventricular contraction. The SA node initiates
impulses, and the AV node provides delay.
QUESTION 7
Which coronary artery primarily supplies blood to the left ventricle?
A. Right coronary artery
B. Left anterior descending artery
C. Circumflex artery
D. Posterior descending artery
Correct Answer: B. Left anterior descending artery
RATIONALE: The left anterior descending (LAD) artery, a branch of the left
coronary artery, supplies blood to the anterior wall of the left ventricle and the
interventricular septum. The right coronary artery supplies the right ventricle. The
circumflex artery supplies the lateral wall.
QUESTION 8
What is the normal duration of the PR interval?
A. 0.04-0.10 seconds
B. 0.12-0.20 seconds
C. 0.20-0.30 seconds
D. 0.30-0.40 seconds
Correct Answer: B. 0.12-0.20 seconds
Questions with Correct Answers & Detailed
Rationales COMPLETE Q&A WITH VERIFIED
ANSWERS AND DETAILED RATIONALES |
OBJECTIVE ASSESSMENT PREP | A+ GRADED
Core Domains Covered:
• Cardiac Anatomy and Physiology
• Cardiac Conduction System
• EKG Waveforms and Intervals
• EKG Lead Placement and Acquisition
• Rhythm Interpretation
• Arrhythmia Identification
• Myocardial Infarction Recognition
• Axis Deviation and Hypertrophy
• Artifact Recognition
• EKG Equipment and Safety
• Clinical Application of EKG
QUESTION 1
Which chamber of the heart receives deoxygenated blood from the superior and
inferior vena cava?
A. Left atrium
B. Right atrium
,C. Left ventricle
D. Right ventricle
Correct Answer: B. Right atrium
RATIONALE: The right atrium receives deoxygenated systemic blood from the
superior vena cava (SVC) and inferior vena cava (IVC). The left atrium receives
oxygenated blood from the lungs via the pulmonary veins. Ventricles are the lower
chambers of the heart responsible for pumping blood out of the heart.
QUESTION 2
The pacemaker cells of the heart are located primarily in which structure?
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Sinoatrial (SA) node
D. Bundle of His
Correct Answer: C. Sinoatrial (SA) node
RATIONALE: The SA node, located in the right atrium, is the primary
pacemaker of the heart, generating electrical impulses at a rate of 60-100 beats per
minute. The AV node is a secondary pacemaker with an intrinsic rate of 40-60
bpm. Purkinje fibers have an intrinsic rate of 20-40 bpm.
QUESTION 3
What is the normal intrinsic firing rate of the sinoatrial (SA) node?
A. 20-40 beats per minute
B. 40-60 beats per minute
C. 60-100 beats per minute
D. 100-160 beats per minute
Correct Answer: C. 60-100 beats per minute
RATIONALE: The SA node normally fires at 60-100 beats per minute,
establishing the normal sinus rhythm. The AV node has an intrinsic rate of 40-60
,bpm, and the Purkinje fibers have an intrinsic rate of 20-40 bpm. Rates above 100
bpm indicate tachycardia.
QUESTION 4
Which layer of the heart is responsible for the contractile function?
A. Epicardium
B. Endocardium
C. Myocardium
D. Pericardium
Correct Answer: C. Myocardium
RATIONALE: The myocardium is the middle layer of the heart wall and is
composed of cardiac muscle cells responsible for contraction. The epicardium is
the outer layer. The endocardium is the inner lining. The pericardium is the fibrous
sac surrounding the heart.
QUESTION 5
The atrioventricular (AV) node is located in which area of the heart?
A. Right atrium near the SA node
B. Inferior portion of the interatrial septum
C. Ventricular septum
D. Left ventricular wall
Correct Answer: B. Inferior portion of the interatrial septum
RATIONALE: The AV node is located in the inferior portion of the interatrial
septum near the tricuspid valve. It receives impulses from the SA node and delays
them briefly before transmitting to the ventricles, allowing for atrial contraction
before ventricular contraction.
QUESTION 6
What is the primary function of the Purkinje fibers?
, A. Initiate cardiac impulses
B. Delay conduction to the ventricles
C. Rapidly conduct impulses throughout the ventricles
D. Supply blood to the heart muscle
Correct Answer: C. Rapidly conduct impulses throughout the ventricles
RATIONALE: Purkinje fibers are specialized conducting cells that rapidly
transmit electrical impulses from the bundle branches throughout the ventricular
myocardium, ensuring coordinated ventricular contraction. The SA node initiates
impulses, and the AV node provides delay.
QUESTION 7
Which coronary artery primarily supplies blood to the left ventricle?
A. Right coronary artery
B. Left anterior descending artery
C. Circumflex artery
D. Posterior descending artery
Correct Answer: B. Left anterior descending artery
RATIONALE: The left anterior descending (LAD) artery, a branch of the left
coronary artery, supplies blood to the anterior wall of the left ventricle and the
interventricular septum. The right coronary artery supplies the right ventricle. The
circumflex artery supplies the lateral wall.
QUESTION 8
What is the normal duration of the PR interval?
A. 0.04-0.10 seconds
B. 0.12-0.20 seconds
C. 0.20-0.30 seconds
D. 0.30-0.40 seconds
Correct Answer: B. 0.12-0.20 seconds
