Question: An ECG shows a chaotic, irregular, continuously undulating baseline with no identifiable P waves, QRS complexes, or T waves. What is the cardiac rhythm?

Answer Options: A. Asystole B. Ventricular fibrillation C. Ventricular tachycardia D. Atrial fibrillation

Answer: B. Ventricular fibrillation Question 13

Question: An ECG shows two pacemaker spikes associated with each cardiac cycle: one stimulates the atrium and a second stimulates the ventricle before ventricular depolarization. What is the cardiac rhythm?

Answer Options: A. Normal sinus rhythm B. Atrioventricular paced rhythm C. Atrial paced rhythm D. Ventricular paced rhythm

Answer: B. Atrioventricular paced rhythm Question 14

Question: An ECG shows a very rapid, highly regular, narrow-complex tachycardia in which distinct P waves cannot be clearly identified. What is the cardiac rhythm?

Answer Options: A. Atrial fibrillation B. Sinus tachycardia C. Ventricular tachycardia D. Supraventricular tachycardia

Answer: D. Supraventricular tachycardia Question 15

Question: An ECG shows chaotic electrical activity with an irregular undulating baseline and no recognizable QRS complexes. What is the cardiac rhythm?

Answer Options: A. Ventricular fibrillation B. Ventricular tachycardia C. Asystole D. Atrial fibrillation

Answer: A. Ventricular fibrillation Question 16

Question: An ECG shows continuous chaotic electrical activity with no discernible P waves or QRS complexes and no organized ventricular rhythm. What is the cardiac rhythm?

Answer Options: A. Asystole B. Idioventricular rhythm C. Ventricular fibrillation D. Ventricular tachycardia

Answer: C. Ventricular fibrillation Question 17

Question: An ECG shows normal sinus P waves followed by narrow QRS complexes, but the R-R intervals gradually shorten and lengthen rather than remaining completely regular. What is the cardiac rhythm?

Answer Options: A. First-degree AV block B. Normal sinus rhythm C. Sinus arrhythmia D. Sinus tachycardia

Answer: C. Sinus arrhythmia Question 18

Question: An ECG shows a regular rhythm between 60 and 100 beats per minute. Each upright P wave is followed by a narrow QRS complex, and the PR interval is within the normal range. What is the cardiac rhythm?

Answer Options: A. First-degree AV block B. Normal sinus rhythm C. Junctional tachycardia D. Sinus tachycardia

Answer: B. Normal sinus rhythm Question 19

Question: An ECG shows very fine, irregular, chaotic electrical activity without identifiable P waves, QRS complexes, or an organized ventricular rhythm. What is the cardiac rhythm?

Answer Options: A. Asystole B. Atrial fibrillation C. Ventricular tachycardia D. Ventricular fibrillation

Answer: D. Ventricular fibrillation Question 20

Question: An ECG shows an underlying sinus rhythm with occasional premature atrial beats. The premature beats occur earlier than expected, have an abnormal P-wave morphology, are followed by narrow QRS complexes, and produce noncompensatory pauses. What is the cardiac rhythm?

Answer Options: A. Sinus rhythm with PACs B. Atrial fibrillation C. Sinus arrhythmia D. Normal sinus rhythm

Answer: A. Sinus rhythm with PACs Question 21

Question: An ECG shows regular P waves and a slower regular ventricular escape rhythm, but there is no consistent relationship between the P waves and QRS complexes. The atria and ventricles are depolarizing independently. What is the cardiac rhythm?

Answer Options: A. Idioventricular rhythm B. Sinus bradycardia with PACs C. Third-degree AV block D. Second-degree AV block Type II

Answer: C. Third-degree AV block Question 22

Question: An ECG shows a slow, regular rhythm at approximately 40–60 beats per minute with narrow QRS complexes. Normal P waves are absent before the QRS complexes, and retrograde P waves may occur after them. What is the cardiac rhythm?

Answer Options: A. Atrial fibrillation B. Sinus bradycardia C. First-degree AV block D. Junctional escape rhythm

Answer: D. Junctional escape rhythm