CVT Electrophysiology Studies & Catheter Ablation 2

Question 1

During programmed electrical stimulation (PES), what is the purpose of delivering extrastimuli (S2, S3)?

Accepted Answer

To induce tachyarrhythmias by scanning through refractory periods

Answer

Extrastimuli are delivered at progressively shorter coupling intervals to identify tissue refractory periods and initiate reentrant arrhythmias.

Question 2

What is the normal range for the AH interval in an EP study?

Accepted Answer

55–125 ms

Answer

The AH interval (atrial-to-His, representing AV nodal conduction) normally measures 55–125 ms and prolongates with vagal tone or AV nodal disease.

Question 3

On a 3D electroanatomical bipolar voltage map, purple/blue color typically represents:

Accepted Answer

Scar tissue with low bipolar voltage (<0.5 mV)

Answer

Purple/blue on bipolar voltage maps indicates dense scar (<0.5 mV), which commonly serves as the substrate for reentrant ventricular tachycardia.

Question 4

Pulmonary vein isolation (PVI) during atrial fibrillation ablation targets pulmonary vein ostia located in the:

Accepted Answer

Left atrium

Answer

AF triggers originate predominantly from the pulmonary vein ostia, which connect to the left atrium; PVI electrically isolates these veins.

Question 5

During RF ablation, what is the primary reason to limit catheter tip temperature to approximately 50–60°C?

Accepted Answer

To prevent steam pops that can cause cardiac perforation

Answer

Excessive temperature (>60°C) causes rapid tissue vaporization, producing steam pops (microexplosions) that risk cardiac perforation or thrombus.

(CVT) Cardiovascular Technologist Certification Practice Test