ACLS ACLS Cardiac Rhythms & ECG Interpretation 2

Question 1

On a monitor strip, you see regular, wide QRS complexes at 180 bpm with no discernible P waves and the patient has a pulse. What is the most likely rhythm?

Accepted Answer

Ventricular tachycardia (VT) with pulse

Answer

Ventricular fibrillation

Answer

Supraventricular tachycardia with aberrancy

Answer

Accelerated idioventricular rhythm

Question 2

Which ECG feature best differentiates a junctional rhythm from a sinus rhythm?

Accepted Answer

Absent, inverted, or retrograde P waves

Answer

QRS duration greater than 120 ms

Answer

PR interval greater than 200 ms

Answer

Right bundle branch block pattern

Question 3

A patient in cardiac arrest has no rhythm visible on the monitor (flat line). After confirming lead connections and gain, what is the appropriate ACLS action?

Accepted Answer

Continue high-quality CPR and administer epinephrine

Answer

Immediately defibrillate

Answer

Administer amiodarone 300 mg

Answer

Check for carotid pulse and stop CPR

Question 4

Which ECG pattern is associated with hyperkalemia and should prompt immediate intervention?

Accepted Answer

Peaked (tall, narrow) T waves, widened QRS, flattened P waves

Answer

Prolonged QT with U waves

Answer

Short PR interval with delta wave

Answer

ST depression in lateral leads

Question 5

A narrow-complex tachycardia at 160 bpm begins and terminates abruptly. Which rhythm does this pattern best describe?

Accepted Answer

Paroxysmal supraventricular tachycardia (PSVT)

Answer

Sinus tachycardia

Answer

Atrial fibrillation

Answer

Multifocal atrial tachycardia

Question 6

In third-degree (complete) AV block, what is the relationship between P waves and QRS complexes?

Accepted Answer

Complete dissociation — P waves and QRS complexes are independent

Answer

Fixed PR interval with all P waves conducted

Answer

Progressive PR lengthening until a beat is dropped

Answer

P waves occur after every other QRS