Arrhythmias/Pacemakers trouble shooting Magdi Sami, MD, FRCP(C), FACC Professor of Medicine, MCGILL Univ. Senior Cardiologist, MUHC.

Arrhythmias/Pacemakers trouble shooting

• Magdi Sami, MD, FRCP(C), FACC

• Professor of Medicine, MCGILL Univ.

• Senior Cardiologist, MUHC

Disclosures

• No conflicts to report for this talk

Learning objectives

• Complex ECG’s arrhythmia analysis

• Basic troubleshooting of pacemaker malfunctions.

PVC ou PAC & abberance?

What is the heart rate?What is the rhythm?What is the heart rate?What is the rhythm?

33 x 6 = 198 bpm

The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/

What is the rate? The rhythm?What is the rate? The rhythm?

Short R deep S in V5, V6 pathognomonic of VT

The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/

52 Y old hypertensive presented with palpitations after jogging

This is a recording from an 80 year old man. He was taking Hytrin, Metoprolol, Adalat, Dyazide and ASA.

Pacemaker trouble shootPacemaker trouble shootOutlineOutline

1.1. Pacemaker codesPacemaker codes

2.2. Pacemaker configurationPacemaker configuration

3.3. ExamplesExamples

Pacemaker CodesPacemaker Codes

PositionPosition

FunctionFunction

11

Chambers Chambers PacedPaced

22

Chambers Chambers SensedSensed

33

Response to Response to Sensed Sensed StimulusStimulus

44

Rate Rate Modulation?Modulation?

O (none)O (none) OO OO O (non-rate O (non-rate responsive)responsive)

A (atrium)A (atrium) AA T (triggered)T (triggered) R (rate R (rate responsive)responsive)

V (ventricle)V (ventricle) VV I (inhibited)I (inhibited)

D (both atrium & D (both atrium & ventricle)ventricle)

Pacemaker ConfigurationsPacemaker ConfigurationsVOOVOO

Indications

Temporary mode some-times used during surgery to prevent interference from electrocautery

Pacemaker ConfigurationsPacemaker ConfigurationsAAIAAI

Indications

Sick sinus syndrome in the absence of AV node disease or atrial fibrillation.

Pacemaker ConfigurationsPacemaker ConfigurationsDDDDDD

Indications1. The combination of AV block and SSS.2. Patients with LV dysfunction and LV hypertrophy

who need coordination of atrial and ventricular contractions to maintain adequate CO.

Problem with Pacemaker?Problem with Pacemaker?

Causes: • Threshold rise (electrolytes, drugs)• Lead dislodgement• Lead fracture• RV infarct

Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005.

Problem with Pacemaker?Problem with Pacemaker?

Causes: • Oversensing• Battery failure• Internal insulation failure• Conductor coil fracture

Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005.

Problem with Pacemaker?Problem with Pacemaker?

Causes: • Crosstalk

Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005.

Problems with PacemakersProblems with Pacemakers

Causes: • Undersensing• Lead Fracture

Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005.

Is this pacemaker capturing?Is this pacemaker capturing?

Atrial sensed, ventricular paced

Consistent with DDD or VDD

The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/

What’s wrong?What’s wrong?

Failure to Pace

The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/

Ce patient as-t’il besoin d,un pacemaker?

Where is the block?

Second Degree A-V Block(Mobitz I or Wenckebach)

Where is the Block?

Mobitz Type II

Third Degree A-V Bloc

ANY QUESTIONS?