PACEMAKER ECGs

Presented By:Yasmeen Kamal

Tanta Rhythm Group (TRG)

A gentleman who had a pacemaker implanted 3 years ago came to your clinic to check on his device.

Unfortunately he forgot his card So…. HOW will you deal with him ?

A 12 Lead ECG is made , what can you see ?

In order to reach a proper diagnosis , you should fulfill the following points

1. Mode of Pacing2. Rate3. Capture function4. Sensing function5. What is the underlying

rhythm?6. What to do next?

No atrial spikes, each spike is followed by ventricular activity so It is Ventricular pacing.HR =80 bpm , no intrinsic ventricular beats , underlying rhythm is AF.

What to do next?

1-sensing function should be assessed by using the specific programmer

2-CHADsVaSc score is calculated to assess the need of OAC

North American Society of Pacing and Electrophysiology/British Pacing and Electrophysiology Group

Modes of pacing

Another Example of paced ECG

Mode :Here , We can see 2 spikes.One preceding the p wave and the other is preceding the R wave and pacing is sequentialSo it is a Dual Chamber Pacemaker.

Rate:By Using Calibers from one atrial spike to the next one.

Capture:Each atrial spike is followed by atrial depolarization and each ventricular spike is followed by Vent. dep.

Sensing Function :Couldn’t be assessed .. 100 % pacing

The underlying Rhythm :It is probably Bi-nodal disease

What to do next?Check the sensing function using the programmerBy lowering both atrial and ventricular rates

So what about this strip?

What about it!!

There are pacemaker spikes followed by atrial activity. There is association between each paced atrial activity and Intrinsic ventricular activityMode is : AAI / DDD

Rate : AP-AP

Capture function of the atrium is appropriate

Sensing function : Atrial sensing couldn’t be assessed

Underlying Rhythm : SA nodal disease

What to do next? Check the mode of pacingIf DDD you should test ventricular captureAnd atrial sensing should be assessed in either modes

DDDAS – VPCapture : ventricular capture is appropriatesensing : Atrial sensing function is appropriateUnderlying rhythm : AV nodal diseaseWhat to do next? Check ventricular sensing by prolonging AV delay

Explain those beats

Capture beat: an intrinsic beat that captures the ventricle

Fusion: a combination between intrinsic and paced events

Pseudofusion: occurs when a spike falls on an intrinsic beat

Paced beatFused beatIntrinsic

“capture” beatPseudo fusion

Mode : DDDCapture :Appropriate in both chambersSensing Function : ok regarding both chambers

Explain this?

Hysteresis Function

Is their Anything wrong?

Take a Quick LOOK at V1

PaceMaker Malfunction

This strip was seen in a Holter Monitoring of a patient who had a VVIR pacemaker and was recently Complaining of

dizziness while playing Basket ball?

Oversensing of myopotentials of pectoralis major muscleOversensing Leads to Underpacing

The pacemaker fails to generate an impulse

What is called “Failure of output”

Ventricular Oversensing

Undersensing

Failure of Capture

Spikes not followed by ventricular eventsPseudo fusion beats “3rd and 5th from lt”

Pacemaker mediated Tachycardia

PMT Initiated by atrial non capture

A strip is taken from a Patient with VVI pacemaker while interrogating the device

Explain?

Magnet Mode Behavior acting temporarily like VOO

Automatic Mode Switching

Any Questions?

Thank You