Cardiac Implantable Electronic Devices

Question 1

Output Failure

Answer 1

Results in a heart rate that is below the programmed lower rate of the pacemaker

Question 2

Undersensing

Oversensing

Answer 2

Undersencing - results in asynchronous pacing

Oversensing - results in inappropriate inhibition of pacing

Question 3

Failure to Capture

Answer 3

Results in pacing spikes that are not followed by QRS

Question 4

When is an ICD recommended

Answer 4

LVEF < 35% with CAD
Hypetropic cardiomyopathy
History of a sustained ventricular arrhythmia

Question 5

Things to consider when transporting pt with malfunctioning ICD

Answer 5

Betablockers
Magnet
Amiodarone
12 Lead

Question 6

What happens when a magnet is applied over a pacemaker

Answer 6

Switches to manufacturer’s programmed magnet mode
Converts patient to asynchronous pacing
Checks the battery status of pulse generator based on preset paced rate
Once magnet is removed pacemaker returns to normal functioning

Question 7

What are the effects of a magnet when applied to an ICD/CRT-D

Answer 7

A constant tone emits for a preset time indicating magnet mode is functioning
Applying a magnet disables the ICD/CRT-D suspends its tachyarrhythmia detection and disables shocks
Applying magnet does not affect the preset pacing feature

Question 8

Antitachycardiac Pacing

Answer 8

works by delivering a pacing stimuli into the excitable gap of a reentrant circuit
During the delivery of ATP, the ICD is also charged in the case ATP doesn’t convert the rhythm
Often the ATP converts teh ventricular rhythm and ICD is not required

Question 9

Cardiac Resynchroniztion Therapy

Answer 9

CRT-P and/or CRT-D are only indicated in pt’s with LV dyssynchrony
In order to synchronize the ventricle contractions, two separate leads are placed - Right ventricle and through coronary sinus to Left ventricle
CRT can be a pacing or defibrillation device