3 Arrhythmias and Conduction Disorders Online Quiz Questions

True or false: In an adult, a heart rate below 60 beats per minute is automatically an emergency.

What is the minimum QRS duration, in milliseconds, that qualifies as a wide QRS?

An ECG shows no consistent discrete P waves and an irregularly irregular ventricular rhythm. Which rhythm best fits this pattern?

Which findings support sinus tachycardia rather than the typical SVT pattern described in the material? Select all that apply.

True or false: A 2:1 AV block can be difficult to classify as Mobitz I or Mobitz II from the ECG alone because there are too few consecutive conducted beats to identify the PR pattern.

What is the upper end of the normal PR interval, in milliseconds?

A tracing shows P waves and QRS complexes occurring independently, with no consistent PR relationship. Which AV block pattern does this indicate?

Which findings are identified as signs of poor perfusion or clinical compromise when assessing a rhythm? Select all that apply.

Describe the ECG characteristics that identify torsades de pointes and the emergency response recommended for sustained polymorphic ventricular tachycardia. Include the qualified role of magnesium described for recurrent cases.

A wide-complex tachycardia cannot be confidently identified. Which approach does the material describe for emergency decision-making?

Which ECG description is characteristic of ventricular fibrillation rather than an organized tachyarrhythmia?

True or false: An ECG rhythm alone is enough to establish that a patient has effective circulation, so checking for a pulse is unnecessary.

A regular rhythm has four large boxes between consecutive R waves. Using the regular-rhythm estimate, what is the heart rate in beats per minute? Calculate $300 \div 4$.

A narrow-complex tachycardia has a normal-shaped P wave before every QRS and speeds up and slows down gradually. Which interpretation best fits this pattern?

What rhythm disturbance is characterized by the temporary disappearance of expected sinus P waves, sometimes followed by an escape beat?

An irregular narrow-complex tachycardia has at least three distinct P-wave shapes and varying PR intervals. Which rhythm best matches these findings?

An ECG shows one conducted QRS for every two P waves. What conclusion about the type of second-degree AV block is supported by this pattern alone?

Higher pacemakers fail to produce or conduct impulses, and a slow backup rhythm appears with usually wide QRS complexes. Which rhythm best fits this description?