Pacemaker and Implantable Device Assessment Flashcards

In the NBG pacemaker coding system, what does the first letter represent?

Answer: Chamber paced

The first position of the NBG code identifies the chamber(s) being paced: O (none), A (atrium), V (ventricle), or D (dual).

What does the letter 'R' in the fourth position of the NBG pacemaker code indicate?

Answer: Rate-responsive pacing

An 'R' in position IV indicates rate modulation, meaning the pacemaker adjusts its rate based on physiological demand using a sensor.

Which pacemaker mode tracks atrial activity and paces the ventricle after a programmed AV delay?

Answer: VDD

VDD mode senses in both chambers but paces only the ventricle, tracking atrial activity and delivering ventricular pacing after the programmed AV delay.

What is the most common primary indication for permanent pacemaker implantation?

Answer: Symptomatic bradycardia

Symptomatic bradycardia, including sick sinus syndrome and high-degree AV block causing symptoms, is the most common indication for permanent pacemaker implantation.

Which vascular access site is most commonly associated with pneumothorax as a complication of pacemaker lead implantation?

Answer: Subclavian vein

Subclavian vein access carries the highest risk of pneumothorax due to its proximity to the lung apex; the cephalic vein cutdown is safer in this regard.

In a DDD pacemaker, what does the 'D' in the third position (response to sensing) indicate?

Answer: The device inhibits in one chamber and triggers in the other

In the response-to-sensing position, 'D' means dual response — the device is inhibited by ventricular sensing and triggered (tracks) by atrial sensing.

Pacemaker syndrome is best described as symptoms caused by which of the following?

Answer: AV dyssynchrony during ventricular pacing

Pacemaker syndrome occurs when ventricular-only pacing (e.g., VVI) causes loss of AV synchrony, leading to retrograde VA conduction and symptoms such as fatigue, dizziness, and hypotension.