Kaiser EKG Exam Questions and Answers 2025/2026 | Complete
Electrocardiography Study Guide, EKG Interpretation, Cardiac Rhythm
Analysis, Arrhythmias, Waveform Recognition, Clinical Case Scenarios,
Practice Test Bank with Verified Answers, Detailed Rationales, and Step-by-
Step EKG Analysis for Nursing and Medical Students
Question 1: Which EKG lead is considered the best for assessing P-wave morphology in sinus rhythm?
A. Lead V1
B. Lead II
C. Lead aVR
D. Lead V6
CORRECT ANSWER: B. Lead II
RATIONALE: Lead II is optimally aligned with the heart's electrical axis during normal sinus rhythm,
providing the clearest visualization of P-wave morphology. The P wave in Lead II is typically upright,
rounded, and measures less than 0.12 seconds in duration and less than 0.25 mV in amplitude when
sinus rhythm is present.
Question 2: What is the normal duration of the PR interval in adults?
A. 0.04-0.08 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
RATIONALE: The PR interval represents the time from the onset of atrial depolarization to the onset of
ventricular depolarization. In adults, the normal PR interval ranges from 0.12 to 0.20 seconds (3-5 small
boxes on standard EKG paper). Values outside this range may indicate conduction abnormalities such as
first-degree AV block or pre-excitation syndromes.
Question 3: Which finding on EKG is most characteristic of left atrial enlargement?
A. Peaked P waves in Lead II >0.25 mV
B. Bifid P wave with duration >0.12 seconds in Lead II
C. Deep S wave in V1
D. Tall R wave in V5
CORRECT ANSWER: B. Bifid P wave with duration >0.12 seconds in Lead II
RATIONALE: Left atrial enlargement produces a characteristic "P mitrale" pattern: a broad, bifid
(notched) P wave with duration exceeding 0.12 seconds in Lead II, reflecting delayed conduction
through the enlarged left atrium. Peaked P waves >0.25 mV suggest right atrial enlargement ("P
pulmonale").
Question 4: In which lead would you expect to see the deepest S wave in a normal adult EKG?
,A. Lead I
B. Lead aVL
C. Lead V1
D. Lead V6
CORRECT ANSWER: C. Lead V1
RATIONALE: Lead V1 is positioned over the right ventricle and typically displays a predominantly
negative QRS complex with a deep S wave in normal adults. This reflects the dominant electrical forces
moving away from V1 toward the left ventricle. The R wave progressively increases and S wave
decreases from V1 to V6 (normal R-wave progression).
Question 5: What EKG finding is pathognomonic for ventricular tachycardia?
A. Heart rate >100 bpm
B. QRS duration >0.12 seconds
C. AV dissociation with capture or fusion beats
D. ST-segment elevation
CORRECT ANSWER: C. AV dissociation with capture or fusion beats
RATIONALE: While wide QRS tachycardia can be either ventricular tachycardia or supraventricular
tachycardia with aberrancy, AV dissociation (independent atrial and ventricular activity) with occasional
capture or fusion beats is pathognomonic for ventricular tachycardia. These findings confirm that
ventricular depolarization is occurring independently of atrial activity.
Question 6: Which electrolyte abnormality is most commonly associated with peaked, tented T
waves?
A. Hypokalemia
B. Hyperkalemia
C. Hypocalcemia
D. Hypernatremia
CORRECT ANSWER: B. Hyperkalemia
RATIONALE: Hyperkalemia causes characteristic EKG changes that progress with increasing potassium
levels: peaked, narrow-based, "tented" T waves are typically the earliest finding (serum K+ >5.5 mEq/L).
As levels rise further, PR prolongation, QRS widening, and eventually sine-wave pattern may occur.
Question 7: What is the normal electrical axis range in the frontal plane for adults?
A. -30° to +90°
B. 0° to +180°
C. -90° to +30°
D. +90° to +180°
CORRECT ANSWER: A. -30° to +90°
,RATIONALE: The normal QRS axis in the frontal plane ranges from -30° to +90°. Axis determination uses
Leads I and aVF: if QRS is positive in both, axis is normal; positive in I and negative in aVF suggests left
axis deviation; negative in I and positive in aVF suggests right axis deviation.
Question 8: Which EKG pattern is diagnostic of acute pericarditis?
A. ST elevation with reciprocal ST depression
B. Diffuse concave-upward ST elevation with PR depression
C. ST elevation with Q waves
D. ST depression with T-wave inversion
CORRECT ANSWER: B. Diffuse concave-upward ST elevation with PR depression
RATIONALE: Acute pericarditis classically presents with diffuse, concave-upward ST-segment elevation
in multiple leads (except aVR and V1) accompanied by PR-segment depression. Unlike myocardial
infarction, there are no reciprocal changes, and ST elevation is present in both anterior and inferior
leads simultaneously.
Question 9: What is the hallmark EKG finding in Wolff-Parkinson-White syndrome?
A. Short PR interval with delta wave
B. Prolonged QT interval
C. Inverted T waves in lateral leads
D. Right bundle branch block pattern
CORRECT ANSWER: A. Short PR interval with delta wave
RATIONALE: WPW syndrome is characterized by a short PR interval (<0.12 seconds) and a slurred
upstroke of the QRS complex called a delta wave, resulting from pre-excitation via an accessory pathway
(bundle of Kent). The QRS is typically widened (>0.12 seconds) due to fusion of normal and pre-excited
conduction.
Question 10: Which lead placement error would cause apparent inferior wall MI pattern?
A. Reversal of right and left arm leads
B. Placement of V1 and V2 too high
C. Reversal of leg leads
D. Placement of V4-V6 too low
CORRECT ANSWER: A. Reversal of right and left arm leads
RATIONALE: Reversal of right and left arm leads causes Lead I to appear inverted and can create
pseudo-inferior MI patterns with apparent ST changes in Leads II, III, and aVF. This artifact can be
recognized by the inverted P wave and QRS in Lead I with normal morphology in other leads.
Question 11: What is the minimum QRS duration that defines bundle branch block?
A. ≥0.08 seconds
B. ≥0.10 seconds
, C. ≥0.12 seconds
D. ≥0.14 seconds
CORRECT ANSWER: C. ≥0.12 seconds
RATIONALE: Bundle branch block is diagnosed when the QRS duration is ≥0.12 seconds (3 small boxes)
with characteristic morphology changes. Right bundle branch block shows rSR' pattern in V1; left bundle
branch block shows broad monophasic R waves in lateral leads with absent Q waves.
Question 12: Which rhythm is characterized by irregularly irregular rhythm with no discernible P
waves?
A. Atrial flutter
B. Multifocal atrial tachycardia
C. Atrial fibrillation
D. Sinus arrhythmia
CORRECT ANSWER: C. Atrial fibrillation
RATIONALE: Atrial fibrillation is defined by an irregularly irregular ventricular rhythm with absent
organized P waves, replaced by fibrillatory waves of varying amplitude and morphology. The atrial rate is
typically 350-600 bpm with variable AV conduction producing irregular ventricular response.
Question 13: What EKG finding suggests right ventricular hypertrophy?
A. R wave in V5 + S wave in V2 >35 mm
B. R wave in V1 >7 mm or R/S ratio in V1 >1
C. Deep S wave in V6
D. Left axis deviation
CORRECT ANSWER: B. R wave in V1 >7 mm or R/S ratio in V1 >1
RATIONALE: Right ventricular hypertrophy produces rightward forces manifesting as tall R waves in
right precordial leads. Criteria include: R wave in V1 >7 mm, R/S ratio in V1 >1, right axis deviation, and
secondary ST-T changes in V1-V3. These findings reflect increased right ventricular mass.
Question 14: Which interval is most affected by heart rate and requires correction for accurate
assessment?
A. PR interval
B. QRS duration
C. QT interval
D. PP interval
CORRECT ANSWER: C. QT interval
RATIONALE: The QT interval varies inversely with heart rate, necessitating correction (QTc) for accurate
interpretation. Common formulas include Bazett's (QTc = QT/√RR) and Fridericia's. Normal QTc is <440
ms in men and <460 ms in women; prolongation increases risk of torsades de pointes.
Question 15: What is the classic EKG pattern of atrial flutter?
Electrocardiography Study Guide, EKG Interpretation, Cardiac Rhythm
Analysis, Arrhythmias, Waveform Recognition, Clinical Case Scenarios,
Practice Test Bank with Verified Answers, Detailed Rationales, and Step-by-
Step EKG Analysis for Nursing and Medical Students
Question 1: Which EKG lead is considered the best for assessing P-wave morphology in sinus rhythm?
A. Lead V1
B. Lead II
C. Lead aVR
D. Lead V6
CORRECT ANSWER: B. Lead II
RATIONALE: Lead II is optimally aligned with the heart's electrical axis during normal sinus rhythm,
providing the clearest visualization of P-wave morphology. The P wave in Lead II is typically upright,
rounded, and measures less than 0.12 seconds in duration and less than 0.25 mV in amplitude when
sinus rhythm is present.
Question 2: What is the normal duration of the PR interval in adults?
A. 0.04-0.08 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
RATIONALE: The PR interval represents the time from the onset of atrial depolarization to the onset of
ventricular depolarization. In adults, the normal PR interval ranges from 0.12 to 0.20 seconds (3-5 small
boxes on standard EKG paper). Values outside this range may indicate conduction abnormalities such as
first-degree AV block or pre-excitation syndromes.
Question 3: Which finding on EKG is most characteristic of left atrial enlargement?
A. Peaked P waves in Lead II >0.25 mV
B. Bifid P wave with duration >0.12 seconds in Lead II
C. Deep S wave in V1
D. Tall R wave in V5
CORRECT ANSWER: B. Bifid P wave with duration >0.12 seconds in Lead II
RATIONALE: Left atrial enlargement produces a characteristic "P mitrale" pattern: a broad, bifid
(notched) P wave with duration exceeding 0.12 seconds in Lead II, reflecting delayed conduction
through the enlarged left atrium. Peaked P waves >0.25 mV suggest right atrial enlargement ("P
pulmonale").
Question 4: In which lead would you expect to see the deepest S wave in a normal adult EKG?
,A. Lead I
B. Lead aVL
C. Lead V1
D. Lead V6
CORRECT ANSWER: C. Lead V1
RATIONALE: Lead V1 is positioned over the right ventricle and typically displays a predominantly
negative QRS complex with a deep S wave in normal adults. This reflects the dominant electrical forces
moving away from V1 toward the left ventricle. The R wave progressively increases and S wave
decreases from V1 to V6 (normal R-wave progression).
Question 5: What EKG finding is pathognomonic for ventricular tachycardia?
A. Heart rate >100 bpm
B. QRS duration >0.12 seconds
C. AV dissociation with capture or fusion beats
D. ST-segment elevation
CORRECT ANSWER: C. AV dissociation with capture or fusion beats
RATIONALE: While wide QRS tachycardia can be either ventricular tachycardia or supraventricular
tachycardia with aberrancy, AV dissociation (independent atrial and ventricular activity) with occasional
capture or fusion beats is pathognomonic for ventricular tachycardia. These findings confirm that
ventricular depolarization is occurring independently of atrial activity.
Question 6: Which electrolyte abnormality is most commonly associated with peaked, tented T
waves?
A. Hypokalemia
B. Hyperkalemia
C. Hypocalcemia
D. Hypernatremia
CORRECT ANSWER: B. Hyperkalemia
RATIONALE: Hyperkalemia causes characteristic EKG changes that progress with increasing potassium
levels: peaked, narrow-based, "tented" T waves are typically the earliest finding (serum K+ >5.5 mEq/L).
As levels rise further, PR prolongation, QRS widening, and eventually sine-wave pattern may occur.
Question 7: What is the normal electrical axis range in the frontal plane for adults?
A. -30° to +90°
B. 0° to +180°
C. -90° to +30°
D. +90° to +180°
CORRECT ANSWER: A. -30° to +90°
,RATIONALE: The normal QRS axis in the frontal plane ranges from -30° to +90°. Axis determination uses
Leads I and aVF: if QRS is positive in both, axis is normal; positive in I and negative in aVF suggests left
axis deviation; negative in I and positive in aVF suggests right axis deviation.
Question 8: Which EKG pattern is diagnostic of acute pericarditis?
A. ST elevation with reciprocal ST depression
B. Diffuse concave-upward ST elevation with PR depression
C. ST elevation with Q waves
D. ST depression with T-wave inversion
CORRECT ANSWER: B. Diffuse concave-upward ST elevation with PR depression
RATIONALE: Acute pericarditis classically presents with diffuse, concave-upward ST-segment elevation
in multiple leads (except aVR and V1) accompanied by PR-segment depression. Unlike myocardial
infarction, there are no reciprocal changes, and ST elevation is present in both anterior and inferior
leads simultaneously.
Question 9: What is the hallmark EKG finding in Wolff-Parkinson-White syndrome?
A. Short PR interval with delta wave
B. Prolonged QT interval
C. Inverted T waves in lateral leads
D. Right bundle branch block pattern
CORRECT ANSWER: A. Short PR interval with delta wave
RATIONALE: WPW syndrome is characterized by a short PR interval (<0.12 seconds) and a slurred
upstroke of the QRS complex called a delta wave, resulting from pre-excitation via an accessory pathway
(bundle of Kent). The QRS is typically widened (>0.12 seconds) due to fusion of normal and pre-excited
conduction.
Question 10: Which lead placement error would cause apparent inferior wall MI pattern?
A. Reversal of right and left arm leads
B. Placement of V1 and V2 too high
C. Reversal of leg leads
D. Placement of V4-V6 too low
CORRECT ANSWER: A. Reversal of right and left arm leads
RATIONALE: Reversal of right and left arm leads causes Lead I to appear inverted and can create
pseudo-inferior MI patterns with apparent ST changes in Leads II, III, and aVF. This artifact can be
recognized by the inverted P wave and QRS in Lead I with normal morphology in other leads.
Question 11: What is the minimum QRS duration that defines bundle branch block?
A. ≥0.08 seconds
B. ≥0.10 seconds
, C. ≥0.12 seconds
D. ≥0.14 seconds
CORRECT ANSWER: C. ≥0.12 seconds
RATIONALE: Bundle branch block is diagnosed when the QRS duration is ≥0.12 seconds (3 small boxes)
with characteristic morphology changes. Right bundle branch block shows rSR' pattern in V1; left bundle
branch block shows broad monophasic R waves in lateral leads with absent Q waves.
Question 12: Which rhythm is characterized by irregularly irregular rhythm with no discernible P
waves?
A. Atrial flutter
B. Multifocal atrial tachycardia
C. Atrial fibrillation
D. Sinus arrhythmia
CORRECT ANSWER: C. Atrial fibrillation
RATIONALE: Atrial fibrillation is defined by an irregularly irregular ventricular rhythm with absent
organized P waves, replaced by fibrillatory waves of varying amplitude and morphology. The atrial rate is
typically 350-600 bpm with variable AV conduction producing irregular ventricular response.
Question 13: What EKG finding suggests right ventricular hypertrophy?
A. R wave in V5 + S wave in V2 >35 mm
B. R wave in V1 >7 mm or R/S ratio in V1 >1
C. Deep S wave in V6
D. Left axis deviation
CORRECT ANSWER: B. R wave in V1 >7 mm or R/S ratio in V1 >1
RATIONALE: Right ventricular hypertrophy produces rightward forces manifesting as tall R waves in
right precordial leads. Criteria include: R wave in V1 >7 mm, R/S ratio in V1 >1, right axis deviation, and
secondary ST-T changes in V1-V3. These findings reflect increased right ventricular mass.
Question 14: Which interval is most affected by heart rate and requires correction for accurate
assessment?
A. PR interval
B. QRS duration
C. QT interval
D. PP interval
CORRECT ANSWER: C. QT interval
RATIONALE: The QT interval varies inversely with heart rate, necessitating correction (QTc) for accurate
interpretation. Common formulas include Bazett's (QTc = QT/√RR) and Fridericia's. Normal QTc is <440
ms in men and <460 ms in women; prolongation increases risk of torsades de pointes.
Question 15: What is the classic EKG pattern of atrial flutter?
