CVT Electrophysiology Studies & Catheter Ablation

Question 1

What is the primary purpose of an electrophysiology (EP) study?

Accepted Answer

To map electrical pathways and identify arrhythmia mechanisms

Answer

To measure cardiac output during exercise

Answer

To assess coronary artery anatomy

Answer

To evaluate valvular function

Question 2

Which catheter position is used to record His bundle electrograms during an EP study?

Accepted Answer

Tricuspid valve region

Answer

Right atrial appendage

Answer

Coronary sinus

Answer

Right ventricular apex

Question 3

What does the HV interval measure in an electrophysiology study?

Accepted Answer

Time from His bundle activation to ventricular depolarization

Answer

Time from sinus node discharge to atrial activation

Answer

Time from atrial pacing to ventricular response

Answer

Time from P-wave onset to QRS complex onset

Question 4

Radiofrequency (RF) catheter ablation destroys arrhythmogenic tissue primarily by:

Accepted Answer

Applying thermal energy to cause localized tissue necrosis

Answer

Freezing cardiac tissue to create conduction block

Answer

Delivering high-voltage shocks to reset the arrhythmia circuit

Answer

Injecting alcohol to destroy accessory pathways

Question 5

In Wolff-Parkinson-White (WPW) syndrome, which EP study finding confirms the presence of an accessory pathway?

Accepted Answer

Short or negative HV interval with ventricular pre-excitation

Answer

Prolonged HV interval greater than 70 ms

Answer

Absence of a recordable His bundle potential

Answer

Complete AV block induced during atrial pacing

Question 6

Why is cryoablation often preferred over RF ablation for AVNRT located close to the AV node?

Accepted Answer

It allows reversible testing (cryomapping) before creating a permanent lesion

Answer

It creates larger lesions with less contact force

Answer

It generates more precise temperature control above 70°C

Answer

It eliminates the need for fluoroscopic guidance

Question 7

During a standard EP study, where is the atrial pacing catheter most commonly placed?

Accepted Answer

Right atrium or coronary sinus

Answer

Left ventricle via retrograde aortic approach

Answer

Pulmonary artery

Answer

Descending aorta