CVT Cardiac Rhythm Management Devices 3

Question 1

A CRT device shows less than 98% biventricular pacing on follow-up. What is the most appropriate first intervention?

Accepted Answer

Optimize AV delay and manage causes of native conduction (e.g., AF)

Answer

Maximizing biventricular pacing percentage—by programming AV delay shorter than intrinsic PR and treating AF that competes with pacing—is the first step before hardware revision.

Question 2

The subcutaneous ICD (S-ICD) is contraindicated in patients who require what function?

Accepted Answer

Antitachycardia pacing or bradycardia pacing support

Answer

Because the S-ICD has no transvenous leads, it cannot provide antitachycardia pacing or chronic bradycardia pacing, limiting its use to patients with no pacing indication.

Question 3

Magnet application to a permanent pacemaker in a non-dependent patient typically results in which response?

Accepted Answer

Asynchronous pacing at a fixed magnet rate

Answer

Magnet application causes most pacemakers to switch to asynchronous (AOO, VOO, or DOO) pacing at a manufacturer-specific magnet rate, bypassing sensing functions.

Question 4

Which electrogram (EGM) characteristic best distinguishes supraventricular tachycardia (SVT) from VT in a dual-chamber ICD?

Accepted Answer

Atrial rate equal to or faster than ventricular rate with 1:1 AV relationship at onset

Answer

When the atrial rate meets or exceeds the ventricular rate with a 1:1 relationship, SVT is favored; VT typically shows VA dissociation or slower atrial rate than ventricular rate.

Question 5

What is the primary purpose of the post-ventricular atrial refractory period (PVARP) in a dual-chamber pacemaker?

Accepted Answer

To prevent sensing of far-field R-waves on the atrial channel

Answer

PVARP prevents the atrial channel from sensing the ventricular event or its far-field signal, thereby avoiding pacemaker-mediated tachycardia and inappropriate tracking.

(CVT) Cardiovascular Technologist Certification Practice Test

(CVT) Cardiovascular Technologist Certification Practice Test

CVT Cardiac Rhythm Management Devices 3