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? The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/ 33 x 6 = 198 bpm

What is the rate? The rhythm? The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/ Short R deep S in V5, V6 pathognomonic of VT

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. QT (ms) 559 QRS axis (degrees) 80                                                                                                         

Pacemaker trouble shoot Outline Pacemaker codes Pacemaker configuration Examples

Pacemaker Codes Position Function 1 Chambers Paced 2 Chambers Sensed 3 Response to Sensed Stimulus 4 Rate Modulation? O (none) O O (non-rate responsive) A (atrium) A T (triggered) R (rate responsive) V (ventricle) V I (inhibited) D (both atrium & ventricle)

Pacemaker Configurations VOO Indications Temporary mode some-times used during surgery to prevent interference from electrocautery

Pacemaker Configurations AAI Indications Sick sinus syndrome in the absence of AV node disease or atrial fibrillation.

Pacemaker Configurations DDD Indications 1. 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? Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005. Causes: Threshold rise (electrolytes, drugs) Lead dislodgement Lead fracture RV infarct

Problem with Pacemaker? Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005. Causes: Oversensing Battery failure Internal insulation failure Conductor coil fracture

Problem with Pacemaker? Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005. Causes: Crosstalk

Problems with Pacemakers Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005. Causes: Undersensing Lead Fracture

Is this pacemaker capturing? The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/ Atrial sensed, ventricular paced Consistent with DDD or VDD

What’s wrong? Failure to Pace The Alan E. Lindsay ECG Learning Center ; http://medstat.med.utah.edu/kw/ecg/ Failure to Pace

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?