1. Which of the following rhythms is considered a medical emergency due to its potential for
rapid deterioration?
A. Sinus tachycardia
B. Atrial fibrillation
C. Ventricular fibrillation
D. First-degree heart block
Answer: C) Ventricular fibrillation
Rationale: Ventricular fibrillation (VF) is a life-threatening dysrhythmia where the heart's
electrical impulses are chaotic, leading to no effective cardiac output. Immediate defibrillation is
required to restore normal rhythm.
2. What is the characteristic feature of atrial fibrillation on an ECG?
A. Sawtooth pattern of P waves
B. Irregularly irregular rhythm with no distinct P waves
C. Wide QRS complexes
D. P waves with a normal PR interval
Answer: B) Irregularly irregular rhythm with no distinct P waves
Rationale: Atrial fibrillation (AF) is characterized by a rapid, disorganized electrical activity in
the atria, leading to an absence of distinct P waves and an irregularly irregular rhythm. This can
result in an increased risk of clot formation.
3. Which medication is commonly used to treat bradycardia caused by sinus node dysfunction?
A. Lidocaine
B. Atropine
C. Amiodarone
D. Adenosine
Answer: B) Atropine
,Rationale: Atropine is an anticholinergic drug that can increase the heart rate by inhibiting the
vagus nerve's effects on the heart. It is often used in cases of symptomatic bradycardia,
particularly when caused by sinus node dysfunction.
4. Which of the following is a typical ECG finding in a patient with a complete heart block
(third-degree AV block)?
A. The P waves are regular and march through the QRS complex.
B. P waves and QRS complexes are completely independent of each other.
C. P waves are seen at a faster rate than the QRS complex.
D. The PR interval is prolonged but consistent.
Answer: B) P waves and QRS complexes are completely independent of each other.
Rationale: In third-degree (complete) AV block, there is no conduction between the atria and
ventricles. This results in a complete dissociation between the P waves and QRS complexes, with
the atrial rate being faster than the ventricular rate.
5. Which of the following is a characteristic feature of a premature ventricular contraction (PVC)
on an ECG?
A. A premature, wide QRS complex without a preceding P wave
B. A narrow QRS complex with a compensatory pause
C. An early P wave followed by a normal QRS complex
D. A prolonged PR interval with an absent QRS complex
Answer: A) A premature, wide QRS complex without a preceding P wave
Rationale: PVCs are premature depolarizations originating from the ventricles. They are
characterized by wide, bizarre QRS complexes, which occur before the next expected sinus beat.
There is typically no preceding P wave.
6. Which of the following rhythms is typically associated with a “sawtooth” pattern of P waves
on an ECG?
A. Atrial fibrillation
B. Atrial flutter
, C. Ventricular tachycardia
D. Sinus tachycardia
Answer: B) Atrial flutter
Rationale: Atrial flutter is characterized by a rapid, regular atrial rhythm with the appearance of
“sawtooth” P waves (flutter waves) on the ECG, due to rapid atrial depolarizations.
7. Which of the following is a common cause of torsades de pointes?
A. Hyperkalemia
B. Hypokalemia
C. Long QT syndrome
D. Hypoxia
Answer: C) Long QT syndrome
Rationale: Torsades de pointes is a form of polymorphic ventricular tachycardia often associated
with a prolonged QT interval, which can result from congenital or acquired long QT syndrome.
8. Which of the following is an important treatment for a patient with symptomatic second-
degree heart block type II?
A. Defibrillation
B. Atropine
C. Permanent pacemaker implantation
D. Adenosine
Answer: C) Permanent pacemaker implantation
Rationale: Type II second-degree heart block is characterized by intermittent failure of
conduction through the AV node, resulting in dropped beats. This type of block often requires
permanent pacemaker implantation.
9. What is the first-line treatment for ventricular fibrillation?
A. Amiodarone
B. Lidocaine
rapid deterioration?
A. Sinus tachycardia
B. Atrial fibrillation
C. Ventricular fibrillation
D. First-degree heart block
Answer: C) Ventricular fibrillation
Rationale: Ventricular fibrillation (VF) is a life-threatening dysrhythmia where the heart's
electrical impulses are chaotic, leading to no effective cardiac output. Immediate defibrillation is
required to restore normal rhythm.
2. What is the characteristic feature of atrial fibrillation on an ECG?
A. Sawtooth pattern of P waves
B. Irregularly irregular rhythm with no distinct P waves
C. Wide QRS complexes
D. P waves with a normal PR interval
Answer: B) Irregularly irregular rhythm with no distinct P waves
Rationale: Atrial fibrillation (AF) is characterized by a rapid, disorganized electrical activity in
the atria, leading to an absence of distinct P waves and an irregularly irregular rhythm. This can
result in an increased risk of clot formation.
3. Which medication is commonly used to treat bradycardia caused by sinus node dysfunction?
A. Lidocaine
B. Atropine
C. Amiodarone
D. Adenosine
Answer: B) Atropine
,Rationale: Atropine is an anticholinergic drug that can increase the heart rate by inhibiting the
vagus nerve's effects on the heart. It is often used in cases of symptomatic bradycardia,
particularly when caused by sinus node dysfunction.
4. Which of the following is a typical ECG finding in a patient with a complete heart block
(third-degree AV block)?
A. The P waves are regular and march through the QRS complex.
B. P waves and QRS complexes are completely independent of each other.
C. P waves are seen at a faster rate than the QRS complex.
D. The PR interval is prolonged but consistent.
Answer: B) P waves and QRS complexes are completely independent of each other.
Rationale: In third-degree (complete) AV block, there is no conduction between the atria and
ventricles. This results in a complete dissociation between the P waves and QRS complexes, with
the atrial rate being faster than the ventricular rate.
5. Which of the following is a characteristic feature of a premature ventricular contraction (PVC)
on an ECG?
A. A premature, wide QRS complex without a preceding P wave
B. A narrow QRS complex with a compensatory pause
C. An early P wave followed by a normal QRS complex
D. A prolonged PR interval with an absent QRS complex
Answer: A) A premature, wide QRS complex without a preceding P wave
Rationale: PVCs are premature depolarizations originating from the ventricles. They are
characterized by wide, bizarre QRS complexes, which occur before the next expected sinus beat.
There is typically no preceding P wave.
6. Which of the following rhythms is typically associated with a “sawtooth” pattern of P waves
on an ECG?
A. Atrial fibrillation
B. Atrial flutter
, C. Ventricular tachycardia
D. Sinus tachycardia
Answer: B) Atrial flutter
Rationale: Atrial flutter is characterized by a rapid, regular atrial rhythm with the appearance of
“sawtooth” P waves (flutter waves) on the ECG, due to rapid atrial depolarizations.
7. Which of the following is a common cause of torsades de pointes?
A. Hyperkalemia
B. Hypokalemia
C. Long QT syndrome
D. Hypoxia
Answer: C) Long QT syndrome
Rationale: Torsades de pointes is a form of polymorphic ventricular tachycardia often associated
with a prolonged QT interval, which can result from congenital or acquired long QT syndrome.
8. Which of the following is an important treatment for a patient with symptomatic second-
degree heart block type II?
A. Defibrillation
B. Atropine
C. Permanent pacemaker implantation
D. Adenosine
Answer: C) Permanent pacemaker implantation
Rationale: Type II second-degree heart block is characterized by intermittent failure of
conduction through the AV node, resulting in dropped beats. This type of block often requires
permanent pacemaker implantation.
9. What is the first-line treatment for ventricular fibrillation?
A. Amiodarone
B. Lidocaine
