1. Pacemakers and Implantable Cardioverter Defibrillators
Dr. Sivaraman Yegya-Raman

2. Temporary and Permanent Cardiac Pacing
Introduction
Temporary pacing : Indications, Technique
Permanent Pacing :
Nomenclature
Indications
Pacing for Hemodynamic Improvement
Pacemaker Implantation, Complications
Implantable Cardioverter Defibrillator

3. Temporary Cardiac Pacing
Transvenous
Transcutaneous
Epicardial
Transesophageal

4. Indications for Temporary Pacing
Acute myocardial infarction with:
CHB, Mobitz type 2 AV block, medically refractory symptomatic bradycardia, alternating BBB, new bifascicular block, new BBB with anterior MI
In absence of acute MI : SSS, CHB, Mobitz type 2 AV block
Treatment of tachyarrhythmias : VT

5. Temporary Transvenous Pacing Electrograms

6. Permanent Pacing

7. The Pacemaker System
Patient
Lead
Lead
Pacemaker
Programmer
Pacemaker

8. Pacemaker Implantation
Transvenous :
Generator implanted anterior to pectoral muscle
Atrial/Ventricular leads via subclavian or cephalic vein
Sensing and pacing threshold
Chest X-ray for pneumothorax, lead position

9. Castle LW, Cook S: Pacemaker radiography
Castle LW, Cook S: Pacemaker radiography. In Ellenbogen KA, Kay GN, Wilkoff BL [eds]: Clinical Cardiac Pacing. Philadelphia, WB Saunders, 1995, p 538.

10. Acute Complications of Pacemaker Implantation
Venous access
Pneumothorax, hemothorax
Air embolism
Perforation of central vein
Inadvertent arterial entry
Lead placement
Brady – tachyarrhythmia
Perforation of heart, vein
Damage to heart valve
Generator
Pocket hematoma
Improper or inadequate connection of lead

11. Delayed Complications of Pacemaker Therapy
Lead-related
Thrombosis/embolization
SVC obstruction
Lead dislodgement
Infection
Lead failure
Perforation, pericarditis
Generator-related
Pain
Erosion, infection
Migration
Damage from radiation, electric shock
Patient-related
Twiddler syndrome

12. Codes Describing Pacemaker Modes
Position 1 2 3 4 5
Function
Chambers Paced
Chambers Sensed
Response to Sensing
Rate Modulation
Multisite pacing
Specific Designations
O=none
A=Atrium
V=Ventricle
D=Dual-Atrium and Ventricle
T=Triggered
I=Inhibited
D=Dual-Triggered and Inhibited
R=Rate modulation
NASPE/BPEG 2002

13. DDD

14. Indications for Pacing for AV Block
Degree
Pacemaker necessary
Pacemaker probably necessary
Pacemaker not necessary
Third
Symptomatic congenital complete heart block
Aquired symptomatic complete heart block
Atrial fibrillation with complete heart block
Acquired asymptomatic complete heart block
Second
Symptomatic type I
Symptomatic type II
Asymptomatic type II
Asymptomatic type I at intra-His or infra-His levels
Asymptomatic type I at supra-His (AV nodal) block
First
Asymptomatic or symptomatic

15. Indications for Pacing for Sinus Node Dysfunction
Pacemaker
Pacemaker probably necessary
Pacemaker not necessary
Symptomatic bradycardia
Symptomatic patients with sinus node dysfunction with documented rates of <40 bpm without a clear-cut association between significant symptoms and the bradycardia
Asymptomatic sinus node dysfunction
Symptomatic sinus bradycardia due to long-term drug therapy of a type and dose for which there is no accepted alternative

16. Case #1
72 year old male with chronic atrial fibrillation of greater than 10 years’ duration is admitted following a syncopal episode. A 2D echo shows LVEF 60%. Telemetry reveals atrial fibrillation with slow ventricular response and pauses of 5 to 6 seconds associated with lightheadedness.
How would you proceed?

17. Case #1
72 year old male with chronic atrial fibrillation of greater than 10 years’ duration is admitted following a syncopal episode. A 2D echo shows markedly dilated left atrium and LVEF 60%. Telemetry reveals atrial fibrillation with slow ventricular response and pauses of 5 to 6 seconds associated with near syncope.
How would you proceed?
Answer: Implant a ventricular rate responsive pacemaker

18. Pacemaker Follow-up GOAL OF FOLLOW-UP
Verify appropriate pacemaker operation
Optimize pacemaker functions
Document findings, changes and final settings in order to provide appropriate patient management

19. “Pacemaker Syndrome” Fatigue, dizziness, hypotension
Caused by pacing the ventricle asynchronously, resulting in AV dissociation or VA conduction
Mechanism: atrial contraction against a closed AV valve and release of atrial natriuretic peptide
Worsened by increasing the ventricular pacing rate, relieved by lowering the pacing rate or upgrading to dual chamber system
Therapy with fludrocortisone/volume expansion NOT helpful

20. Sources of Electromagnetic Interference
Medical
MRI
Lithotripsy
Electrocautery/cryosurgery
External defibrillators
Therapeutic radiation
Nonmedical
Arc welding equipment
Automobile engines
Radar Transmitters

21. Biventricular Pacing

22. Normal Conduction Is Important
Normal conduction allows for prompt and synchronous activation of the atria and ventricles
Results in a brief P wave, PR interval and a narrow QRS
Sinus
node AV

23. Cardiomyopathy, LBBB, Heart Failure
Sinus node
Delayed lateral wall contraction
Disorganized ventricular contraction
Decreased pumping efficiency AV
node
Conduction block

24. Heart Failure Bifocal Ventricular Pacing
Intraventricular Activation
Organized ventricular activation sequence
Coordinated septal and free-wall contraction
Improved pumping efficiency
Sinus node AV
node
Stimulation therapy
Conduction block

25. Bi-Ventricular Pacing
Right atrial lead
Coronary sinus lead
Right ventricular lead
N Engl J Med 2003

26. SVC coil
RA lead
LV lead
RV coil

27. RA lead
LV lead
RV lead

28. Bi-V Pace

29. Implantable Cardioverter Defibrillator (ICD)

30. ICD Implantation
Secondary prevention: Prevention of SCD in patients with prior VF or sustained VT.
Primary prevention: Prevention of SCD in individuals without a h/o VF or sustained VT.

31. Indications For ICD
VF/sustained unstable VT not in the setting of a completely reversible cause.
LVEF ≤ 35%, CHF NYHA class II, III.
Ischemic dilated cardiomyopathy, LVEF ≤ 40%, NSVT and inducible sustained VT.
Syncope, LV dysfunction, inducible sustained VT.
High risk patients with: hypertrophic cardiomyopathy, LQT syndrome, RV dysplasia, Brugada syndrome

32. Ellenbogen K A, 2007

33. NYHA functional Class III or ambulatory Class IV
ACC/AHA/HRS 2008 Guidelines: Systolic Heart Failure - Cardiac Resynchronization Therapy (CRT) Recommendations
LVEF ≤ 35%
QRS ≥ 120 msec
NYHA functional Class III or ambulatory Class IV
Optimal medical therapy

34. “Typical Case”
58 year old male, CAD, prior MI, EF 28%, CHF, NYHA class II, Medications: Furosemide 40 mg, Enalapril 20 BID, Aldactone 25 qd, Carvedilol 25 BID, no syncope or VT, ECG: Sinus rhythm, old anteroseptal MI, QRS 92 msec
Based on available trial data, you would suggest:
A. Treating medically without device implantation
B. Implanting an ICD
C. Implanting an ICD with biventricular pacing capabilities (3 leads)

35. Typical Case
Q: 60 year old female presents with a 1 year h/o non ischemic dilated cardiomyopathy, CHF NYHA class III despite maximum medical therapy, LVEF 20% and LBBB with QRS 170 msec. What device is indicated?
A: Bi-Ventricular ICD

36. 1° Prevention: Clinical Device Algorithm
If Non –Ischemic Dilated Cardiomyopathy:
& EF ≤ 35%
ACE inhibitors, Beta Blockers
ICD
If LVEF ≤ 35%, CHF Class III-IV, QRS ≥ 120 ms
BiV ICD

37. Magnet Application on Pacemaker/ICD
Disables sensing
Changes to VOO or DOO mode
Useful if cautery is being used in PPM dependent pt.
ICD:
Disables Tachycardia sensing
Useful at bedside if pt. has ventricular lead fracture or Afib with rapid ventricular response causing ICD shocks
Prevents ICD shock during cautery application at surgery

38. Future Directions Leadless pacing Biological pacemakers
Subcutaneous ICD