PROPHECY EKG EXAM – EXAM-STYLE QUESTIONS AND ANSWERS | VERIFIED
AND WELL DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS |
2026/27 LATEST UPDATE | EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A patient's cardiac monitor displays a rhythm with a heart rate of 52 beats
per minute and a regular rhythm. The P waves are upright and consistent in
morphology, preceding each QRS complex. The PR interval measures 0.24
seconds, and the QRS duration is 0.08 seconds. What is the most appropriate
interpretation of this rhythm?
A. Normal sinus rhythm with first-degree AV block
B. Sinus bradycardia with first-degree AV block
C. Sinus arrhythmia with a prolonged PR interval
D. Junctional bradycardia with retrograde P waves
Correct Answer: B. Sinus bradycardia with first-degree AV block
Rationale: The presence of upright, consistent P waves preceding each QRS complex
confirms a sinus origin. The rate is below 60 beats per minute, defining bradycardia.
The prolonged PR interval (>0.20 seconds) is consistent with a first-degree AV
block. Option A is incorrect because the rate is not within the normal range of 60-
100 bpm. Option C is incorrect because the rhythm is regular, not irregular as seen
in sinus arrhythmia. Option D is incorrect because the P waves are upright, not
retrograde (inverted in leads II, III, and aVF), which would indicate a junctional
origin.
2. The lead II rhythm strip of a patient complaining of palpitations and
lightheadedness shows an irregularly irregular rhythm with no discernible P
,waves and a ventricular rate of 110 beats per minute. Which of the following is
the most appropriate initial action?
A. Administer a 6mg adenosine IV push
B. Perform synchronized cardioversion
C. Assess the patient's hemodynamic status
D. Administer an initial dose of amiodarone
Correct Answer: C. Assess the patient's hemodynamic status
Rationale: The rhythm strip describes atrial fibrillation with a rapid ventricular
response. The immediate priority is to assess the patient's hemodynamic stability, as
this will guide further management (e.g., rate control, rhythm control, or electrical
cardioversion). Option A and B are interventions that may be indicated but are not
the first step without a full clinical assessment. Option D is an antiarrhythmic that
is not the immediate first-line therapy for rate control in a stable patient; the initial
step is always to assess stability.
3. A patient's monitor shows a sudden change from a normal sinus rhythm to a
wide-complex tachycardia at a rate of 180 beats per minute. The patient is
awake, anxious, and has a blood pressure of 100/68 mmHg. The QRS complex
is broad and bizarre, and there are no discernible P waves. What is the best
initial treatment for this patient?
A. Immediate defibrillation
B. Vagal maneuvers and 6mg adenosine IV
C. IV administration of amiodarone 150mg
D. Synchronized cardioversion
,Correct Answer: D. Synchronized cardioversion
Rationale: The scenario describes an unstable patient (symptoms of anxiety,
borderline blood pressure) with a wide-complex tachycardia (likely ventricular
tachycardia). For an unstable patient with a tachyarrhythmia, synchronized
cardioversion is the treatment of choice. Option A, defibrillation, is for pulseless
rhythms. Option B, adenosine, may be used for regular, monomorphic wide-
complex tachycardia if it is of supraventricular origin, but cardioversion is preferred
here due to instability. Option C, amiodarone, is an option for stable patients with
VT, but the patient's instability makes electrical cardioversion the priority.
4. Which of the following best describes the mechanism of impulse formation
in sinus arrhythmia?
A. A fixed conduction delay in the AV node
B. Alternating firing from two different sinoatrial foci
C. Phasic variation in the autonomic tone affecting the SA node
D. Re-entry pathways within the ventricular myocardium
Correct Answer: C. Phasic variation in the autonomic tone affecting the SA
node
Rationale: Sinus arrhythmia is a normal variation of sinus rhythm where the heart
rate increases with inspiration (increased sympathetic tone) and decreases with
expiration (increased vagal tone). This is due to phasic changes in autonomic input
to the sinoatrial node. Option A describes first-degree AV block. Option B describes
a wandering atrial pacemaker. Option D describes the mechanism for ventricular
tachycardia or fibrillation.
, 5. A 12-lead EKG shows a QRS duration of 0.14 seconds, a sinus rhythm at 85
bpm, and a leftward axis of -30 degrees. In lead V1, the QRS complex is
predominantly negative, and in lead V6, it is broad and notched. These findings
are most consistent with a:
A. Right bundle branch block
B. Left bundle branch block
C. Left anterior fascicular block
D. Intraventricular conduction delay
Correct Answer: B. Left bundle branch block
Rationale: A widened QRS (>0.12 seconds) with a characteristic pattern of a broad,
notched R wave in the left-sided leads (I, aVL, V5, V6) and a deep, wide S wave in
the right-sided leads (V1, V2) is diagnostic of a left bundle branch block. The left
axis deviation further supports this diagnosis. Option A, RBBB, would show a
positive deflection (RSR') in V1. Option C, a fascicular block, would not cause such a
profound QRS widening. Option D is a non-specific diagnosis when a bundle
branch block pattern isn't clearly identifiable.
6. A patient with a history of a myocardial infarction presents with palpitations.
The monitor shows a rhythm with a rate of 120 bpm, a regularly irregular
pattern, and a "group beating" appearance. The PR interval is constant, but the
QRS complexes drop out in a predictable pattern. What type of AV block is
this?
AND WELL DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS |
2026/27 LATEST UPDATE | EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A patient's cardiac monitor displays a rhythm with a heart rate of 52 beats
per minute and a regular rhythm. The P waves are upright and consistent in
morphology, preceding each QRS complex. The PR interval measures 0.24
seconds, and the QRS duration is 0.08 seconds. What is the most appropriate
interpretation of this rhythm?
A. Normal sinus rhythm with first-degree AV block
B. Sinus bradycardia with first-degree AV block
C. Sinus arrhythmia with a prolonged PR interval
D. Junctional bradycardia with retrograde P waves
Correct Answer: B. Sinus bradycardia with first-degree AV block
Rationale: The presence of upright, consistent P waves preceding each QRS complex
confirms a sinus origin. The rate is below 60 beats per minute, defining bradycardia.
The prolonged PR interval (>0.20 seconds) is consistent with a first-degree AV
block. Option A is incorrect because the rate is not within the normal range of 60-
100 bpm. Option C is incorrect because the rhythm is regular, not irregular as seen
in sinus arrhythmia. Option D is incorrect because the P waves are upright, not
retrograde (inverted in leads II, III, and aVF), which would indicate a junctional
origin.
2. The lead II rhythm strip of a patient complaining of palpitations and
lightheadedness shows an irregularly irregular rhythm with no discernible P
,waves and a ventricular rate of 110 beats per minute. Which of the following is
the most appropriate initial action?
A. Administer a 6mg adenosine IV push
B. Perform synchronized cardioversion
C. Assess the patient's hemodynamic status
D. Administer an initial dose of amiodarone
Correct Answer: C. Assess the patient's hemodynamic status
Rationale: The rhythm strip describes atrial fibrillation with a rapid ventricular
response. The immediate priority is to assess the patient's hemodynamic stability, as
this will guide further management (e.g., rate control, rhythm control, or electrical
cardioversion). Option A and B are interventions that may be indicated but are not
the first step without a full clinical assessment. Option D is an antiarrhythmic that
is not the immediate first-line therapy for rate control in a stable patient; the initial
step is always to assess stability.
3. A patient's monitor shows a sudden change from a normal sinus rhythm to a
wide-complex tachycardia at a rate of 180 beats per minute. The patient is
awake, anxious, and has a blood pressure of 100/68 mmHg. The QRS complex
is broad and bizarre, and there are no discernible P waves. What is the best
initial treatment for this patient?
A. Immediate defibrillation
B. Vagal maneuvers and 6mg adenosine IV
C. IV administration of amiodarone 150mg
D. Synchronized cardioversion
,Correct Answer: D. Synchronized cardioversion
Rationale: The scenario describes an unstable patient (symptoms of anxiety,
borderline blood pressure) with a wide-complex tachycardia (likely ventricular
tachycardia). For an unstable patient with a tachyarrhythmia, synchronized
cardioversion is the treatment of choice. Option A, defibrillation, is for pulseless
rhythms. Option B, adenosine, may be used for regular, monomorphic wide-
complex tachycardia if it is of supraventricular origin, but cardioversion is preferred
here due to instability. Option C, amiodarone, is an option for stable patients with
VT, but the patient's instability makes electrical cardioversion the priority.
4. Which of the following best describes the mechanism of impulse formation
in sinus arrhythmia?
A. A fixed conduction delay in the AV node
B. Alternating firing from two different sinoatrial foci
C. Phasic variation in the autonomic tone affecting the SA node
D. Re-entry pathways within the ventricular myocardium
Correct Answer: C. Phasic variation in the autonomic tone affecting the SA
node
Rationale: Sinus arrhythmia is a normal variation of sinus rhythm where the heart
rate increases with inspiration (increased sympathetic tone) and decreases with
expiration (increased vagal tone). This is due to phasic changes in autonomic input
to the sinoatrial node. Option A describes first-degree AV block. Option B describes
a wandering atrial pacemaker. Option D describes the mechanism for ventricular
tachycardia or fibrillation.
, 5. A 12-lead EKG shows a QRS duration of 0.14 seconds, a sinus rhythm at 85
bpm, and a leftward axis of -30 degrees. In lead V1, the QRS complex is
predominantly negative, and in lead V6, it is broad and notched. These findings
are most consistent with a:
A. Right bundle branch block
B. Left bundle branch block
C. Left anterior fascicular block
D. Intraventricular conduction delay
Correct Answer: B. Left bundle branch block
Rationale: A widened QRS (>0.12 seconds) with a characteristic pattern of a broad,
notched R wave in the left-sided leads (I, aVL, V5, V6) and a deep, wide S wave in
the right-sided leads (V1, V2) is diagnostic of a left bundle branch block. The left
axis deviation further supports this diagnosis. Option A, RBBB, would show a
positive deflection (RSR') in V1. Option C, a fascicular block, would not cause such a
profound QRS widening. Option D is a non-specific diagnosis when a bundle
branch block pattern isn't clearly identifiable.
6. A patient with a history of a myocardial infarction presents with palpitations.
The monitor shows a rhythm with a rate of 120 bpm, a regularly irregular
pattern, and a "group beating" appearance. The PR interval is constant, but the
QRS complexes drop out in a predictable pattern. What type of AV block is
this?
