2. Pacemakers Jonathan MacCabe November 15, 2004

3. Pacemaker Indications Acquired A/V block in Adults Acquired A/V block in Adults –Class I: There is general agreement that permanent pacemakers should be implanted. Complete heart block, permanent or intermittent, at an anatomic level associated with any on of the following complications: Complete heart block, permanent or intermittent, at an anatomic level associated with any on of the following complications: –Symptomatic bradycardia. In the presence of complete heart block symptoms must be presumed to be due the heart block unless proved otherwise –Congestive heart failure –Ectopic rhythms and other medical conditions that require drugs that suppress the automaticity of escape rhythms and result in symptomatic bradycardia. –Documented periods of asystole >= 3.0 s or any escape rate = 3.0 s or any escape rate <40/min. in symptom free patients –Confusional states that clear with temporary pacing –Post A/V junctional ablation, myotonic dystrophy

4. Pacemaker Indications Acquired A/V block in Adults Acquired A/V block in Adults –Class I: There is general agreement that permanent pacemakers should be implanted. Second degree A/V block permanent or intermittent, regardless of the type or the site of the block, with symptomatic bradycardia. Second degree A/V block permanent or intermittent, regardless of the type or the site of the block, with symptomatic bradycardia. Atrial fibrillation, Atrial flutter and rare cases of SVT with complete or advanced A/V block, bradycardia and any of the conditions in A1. The bradycardia must be unrelated to digitalis or drugs known to impair A/V conduction. Atrial fibrillation, Atrial flutter and rare cases of SVT with complete or advanced A/V block, bradycardia and any of the conditions in A1. The bradycardia must be unrelated to digitalis or drugs known to impair A/V conduction.

5. Pacemaker Indications Acquired A/V block in Adults Acquired A/V block in Adults –Class II: Conditions in which permanent pacemakers are frequently used but there is some divergence of opinion about whether they are needed. Asymptotic complete heart block, permanent or intermittent, at any anatomic site, with ventricular rates of 40/min. or faster Asymptotic complete heart block, permanent or intermittent, at any anatomic site, with ventricular rates of 40/min. or faster Asymptomatic type ll second degree block, permanent or intermittent Asymptomatic type ll second degree block, permanent or intermittent Asymptomatic type I second degree block at intra-His or infra-His levels. Asymptomatic type I second degree block at intra-His or infra-His levels. –Class III: Conditions in which there is general agreement that pacemakers are not necessary. First degree A/V block First degree A/V block Asymptomatic type 1 second degree A/V block at the supra- his level. Asymptomatic type 1 second degree A/V block at the supra- his level.

6. Pacemaker Indications AV Block Associated with Myocardial Infarction: AV Block Associated with Myocardial Infarction: –Class I: There is general agreement that permanent pacemakers should be implanted. Persistent advanced second degree A/V block or complete heart block after acute myocardial infarction with block in he His-Purkinje system Persistent advanced second degree A/V block or complete heart block after acute myocardial infarction with block in he His-Purkinje system Patients with transient advanced A/V block and associated bundle branch block Patients with transient advanced A/V block and associated bundle branch block

7. Pacemaker Indications AV Block Associated with Myocardial Infarction: AV Block Associated with Myocardial Infarction: –Class II: Conditions in which permanent pacemakers are frequently used but there is some divergence of opinion about whether they are needed. Patients with persistent advanced block in the A/V node Patients with persistent advanced block in the A/V node –Class III: Conditions in which there is general agreement that pacemakers are not necessary. Transient A/V conduction disturbances in the absence of intraventricular conduction defects Transient A/V conduction disturbances in the absence of intraventricular conduction defects Transient A/V block in the presence of isolated left anterior hemiblock Transient A/V block in the presence of isolated left anterior hemiblock Acquired left anterior hemiblock in the absence of A/V block. Acquired left anterior hemiblock in the absence of A/V block.

8. Pacemaker Indications Bifasicular and Trifasicular Block (chronic) Bifasicular and Trifasicular Block (chronic) –Class I: There is general agreement that permanent pacemakers should be implanted. Bifasicular block with intermittent complete heart block associated with symptomatic bradycardia Bifasicular block with intermittent complete heart block associated with symptomatic bradycardia Bifasicular or Trifasicular block with intermittent type ll second degree A/V block without symptoms attributable to the heart block. Bifasicular or Trifasicular block with intermittent type ll second degree A/V block without symptoms attributable to the heart block.

9. Pacemaker Indications Bifasicular and Trifasicular Block (chronic) Bifasicular and Trifasicular Block (chronic) –Class II: Conditions in which permanent pacemakers are frequently used but there is some divergence of opinion about whether they are needed. Bifasicular or trifasicular block with syncope that is not proved to be due to complete heart block, but other possible causes for syncope are not identifiable Bifasicular or trifasicular block with syncope that is not proved to be due to complete heart block, but other possible causes for syncope are not identifiable Markedly prolonged HV (>100ms) Markedly prolonged HV (>100ms) Pacing-induced infra-His block Pacing-induced infra-His block –Class III: Conditions in which there is general agreement that pacemakers are not necessary. Fasicular block without A/V block or symptoms Fasicular block without A/V block or symptoms Fasicular block with first degree block without symptoms Fasicular block with first degree block without symptoms

10. Pacemaker Indications Sinus Node Dysfunction: Sinus Node Dysfunction: –Class I: There is general agreement that permanent pacemakers should be implanted. Sinus node dysfunction with documented symptomatic bradycardia. In some patients this will occur as a consequence of long-term (essential) drug therapy of type and dose for which there are no acceptable alternatives. Sinus node dysfunction with documented symptomatic bradycardia. In some patients this will occur as a consequence of long-term (essential) drug therapy of type and dose for which there are no acceptable alternatives. –Class II: Conditions in which permanent pacemakers are frequently used but there is some divergence of opinion about whether they are needed. Sinus node dysfunction occurring spontaneously or as a result of necessary drug therapy, with heart rates <40/min. when a clear association between significant symptoms consistent with bradycardia and the actual presence of bradycardia has not been documented. Sinus node dysfunction occurring spontaneously or as a result of necessary drug therapy, with heart rates <40/min. when a clear association between significant symptoms consistent with bradycardia and the actual presence of bradycardia has not been documented.

11. Pacemaker Indications Sinus Node Dysfunction: Sinus Node Dysfunction: –Class III: Conditions in which there is general agreement that pacemakers are not necessary. Sinus node dysfunction in asymptomatic patients including those in whom substantial sinus bradycardia (heart rate < 40/min.) is a consequence of long-term drug treatment Sinus node dysfunction in asymptomatic patients including those in whom substantial sinus bradycardia (heart rate < 40/min.) is a consequence of long-term drug treatment Sinus node dysfunction in patients in whom symptoms suggestive of bradycardia are clearly documented not to be associate with a slow heart rate. Sinus node dysfunction in patients in whom symptoms suggestive of bradycardia are clearly documented not to be associate with a slow heart rate.

12. Pacemaker Indications Hypersensitive Carotid Sinus and Neurovascular Syndromes Hypersensitive Carotid Sinus and Neurovascular Syndromes –Class I: There is general agreement that permanent pacemakers should be implanted. Recurrent syncope associates with clear, spontaneous events provoked by carotid sinus stimulation; minimal carotid sinus pressure induces asystole of >3 sec. duration in the absence of a medication that depresses the sinus node or A/V node Recurrent syncope associates with clear, spontaneous events provoked by carotid sinus stimulation; minimal carotid sinus pressure induces asystole of >3 sec. duration in the absence of a medication that depresses the sinus node or A/V node –Class II: Conditions in which permanent pacemakers are frequently used but there is some divergence of opinion about whether they are needed. Recurrent syncope without clear, provocative events and with a hypersensitive cadrioinhibitory response. Recurrent syncope without clear, provocative events and with a hypersensitive cadrioinhibitory response. Syncope with associated bradycardia reproduced by a head- up tilt with or without isoproterenol or other forms of provocative maneuvers and in which a temporary pacemaker and second provocative test can establish the likely benefits of a permanent pacemaker Syncope with associated bradycardia reproduced by a head- up tilt with or without isoproterenol or other forms of provocative maneuvers and in which a temporary pacemaker and second provocative test can establish the likely benefits of a permanent pacemaker

13. Pacemaker Indications Hypersensitive Carotid Sinus and Neurovascular Syndromes Hypersensitive Carotid Sinus and Neurovascular Syndromes –Class III: Conditions in which there is general agreement that pacemakers are not necessary. A hyperactive cardioinhibitory response to carotid sinus stimulation in the absence of symptoms. A hyperactive cardioinhibitory response to carotid sinus stimulation in the absence of symptoms. Vague symptoms, such s dizziness or light-headedness or both, with a hyperactive cardioinhibitory response to carotid sinus stimulation. Vague symptoms, such s dizziness or light-headedness or both, with a hyperactive cardioinhibitory response to carotid sinus stimulation. Recurrent syncope, light-headedness or dizziness in the absence of a cardioinhibitory response. Recurrent syncope, light-headedness or dizziness in the absence of a cardioinhibitory response.

14. The NASPE / BPEG Generic (I.C.H.D.)

15. The NASPE/BPEG Generic (NBG) Code Position Category Letters Used Manufac- turer’s Designation Only IIIIII Chamber(s) Paced Chamber(s) Sensed Response to Sensing Programmability, rate modulation Antitachy- arrhythmia Function(s) O-None P-Simple Programmable M-Multi- Programmable C-Communicating R-Rate modulation O-None A-Atrium V-Ventricle D-Dual (A+V) S- Single (A or V) S- Single (A or V) O-None A-Atrium V-Ventricle D-Dual (A+V) O-None T-Triggered I-Inhibited D-Dual (T+I) O-None P-Pacing (antitachy- arrhythmia) S-Shock D-Dual (P+S) IV V

16. Codes Are Combined To Describe: The mode of pacing The mode of pacing The mode of sensing The mode of sensing How the pacemaker will respond to the presence or absence of intrinsic beats How the pacemaker will respond to the presence or absence of intrinsic beats - AOO - AAI - VOO - VVI

17. The NASPE/BPEG Generic (NBG) Code Position Category Letters Used Manufac- turer’s Designation Only IIIIII Chamber(s) Paced Chamber(s) Sensed Response to Sensing Programmability, rate modulation Antitachy- arrhythmia Function(s) O-None P-Simple Programmable M-Multi- Programmable C-Communicating R-Rate modulation O-None A-Atrium V-Ventricle D-Dual (A+V) S- Single (A or V) S- Single (A or V) O-None A-Atrium V-Ventricle D-Dual (A+V) O-None T-Triggered I-Inhibited D-Dual (T+I) O-None P-Pacing (antitachy- arrhythmia) S-Shock D-Dual (P+S) IV V

18. The NASPE/BPEG Generic (NBG) Code Position Category Letters Used Manufac- turer’s Designation Only IIIIII Chamber(s) Paced Chamber(s) Sensed Response to Sensing Programmability, rate modulation Antitachy- arrhythmia Function(s) O-None P-Simple Programmable M-Multi- Programmable C-Communicating R-Rate modulation O-None A-Atrium V-Ventricle D-Dual (A+V) S- Single (A or V) S- Single (A or V) O-None A-Atrium V-Ventricle D-Dual (A+V) O-None T-Triggered I-Inhibited D-Dual (T+I) O-None P-Pacing (antitachy- arrhythmia) S-Shock D-Dual (P+S) IV V

19. The NASPE/BPEG Generic (NBG) Code Position Category Letters Used Manufac- turer’s Designation Only IIIIII Chamber(s) Paced Chamber(s) Sensed Response to Sensing Programmability, rate modulation Antitachy- arrhythmia Function(s) O-None P-Simple Programmable M-Multi- Programmable C-Communicating R-Rate modulation O-None A-Atrium V-Ventricle D-Dual (A+V) S- Single (A or V) S- Single (A or V) O-None A-Atrium V-Ventricle D-Dual (A+V) O-None T-Triggered I-Inhibited D-Dual (T+I) O-None P-Pacing (antitachy- arrhythmia) S-Shock D-Dual (P+S) IV V

20. The NASPE/BPEG Generic (NBG) Code Position Category Letters Used Manufac- turer’s Designation Only IIIIII Chamber(s) Paced Chamber(s) Sensed Response to Sensing Programmability, rate modulation Antitachy- arrhythmia Function(s) O-None P-Simple Programmable M-Multi- Programmable C-Communicating R-Rate modulation O-None A-Atrium V-Ventricle D-Dual (A+V) S- Single (A or V) S- Single (A or V) O-None A-Atrium V-Ventricle D-Dual (A+V) O-None T-Triggered I-Inhibited D-Dual (T+I) O-None P-Pacing (antitachy- arrhythmia) S-Shock D-Dual (P+S) IV V

21. VOO Ventricular lead Ventricular pacing Ventricular asynchronous pacing at lower programmed pacing rate * No sensing

22. AOO * Atrial lead Atrial asynchronous pacing at lower programmed pacing rate Atrial pacing No sensing

23. VVI * Ventricular lead Sensed intrinsic QRS inhibits ventricular pacing Ventricular pacing Ventricular sensing

24. AAI * Atrial lead Intrinsic P wave inhibits atrial pacing Atrial pacing Atrial sensing

25. Dual Chamber Pacing

26. T / I * * Atrial lead Ventricular Lead Pacing in both the atrium and ventricle Sensing in both the atrium and ventricle Intrinsic P wave and intrinsic QRS can inhibit pacing Intrinsic P Wave can “trigger” a paced QRS DDD I

27. DDD pacing Dual-chamber pacing capable of pacing and sensing in both the atrial and ventricular chambers of the heart Dual-chamber pacing capable of pacing and sensing in both the atrial and ventricular chambers of the heart 4 distinct patterns can be observed with DDD pacing 4 distinct patterns can be observed with DDD pacing –Sensing in the atrium and sensing in the ventricle –Pacing in the atrium and sensing in the ventricle –Sensing in the atrium and pacing in the ventricle (“P wave tracking”) –Pacing in the atrium and pacing in the ventricle

28. DDD pacing Example of sensing in both the atrium and the ventricle (inhibiting in both the atrium and the ventricle) Example of sensing in both the atrium and the ventricle (inhibiting in both the atrium and the ventricle)

29. DDD pacing Example of pacing in the atrium with sensing (inhibition of pacing) in the ventricle Example of pacing in the atrium with sensing (inhibition of pacing) in the ventricle

30. DDD pacing Example of sensing in the atrium (inhibition of atrial pacing) and pacing in the ventricle Example of sensing in the atrium (inhibition of atrial pacing) and pacing in the ventricle Also known as “P wave tracking” Also known as “P wave tracking”

31. DDD pacing Example of atrial pacing and ventricular pacing (no inhibition of pacing) Example of atrial pacing and ventricular pacing (no inhibition of pacing)

32. DDD Pacing Adapts to changes post-implant Adapts to changes post-implant May resemble AAI, VAT, VDD, DVI modes May resemble AAI, VAT, VDD, DVI modes Will strive to maintain AV synchrony with variable atrial rates and AV conduction Will strive to maintain AV synchrony with variable atrial rates and AV conduction

33. Cardiac Output = Stroke Volume x Heart Rate AV Synchrony Facilitates venous return Facilitates venous return Increases LVEDP Increases LVEDP Maintains appropriate opening and closing of A-V valves Maintains appropriate opening and closing of A-V valves

34. Loss of AV Synchrony Pacemaker Syndrome Shortness of breath Shortness of breath Fatigue Fatigue Headache Headache Syncope Syncope Vertigo Vertigo CHF, Pulmonary Edema CHF, Pulmonary Edema Dizziness Dizziness Palpitations Palpitations Pulsations in the neck Pulsations in the neck Chest pain Chest pain Near Syncope Near Syncope Confusion Confusion

35. Loss of atrial contribution Loss of atrial contribution Decrease in stroke volume Decrease in stroke volume Decrease in cardiac output Decrease in cardiac output Decrease in cerebral perfusion Decrease in cerebral perfusion Decrease in coronary blood flow Decrease in coronary blood flow Dual-chamber pacing Dual-chamber pacing Normal atrial sensing & capture Normal atrial sensing & capture Appropriate AV Delay Appropriate AV Delay Hemodynamic Penalties From Loss Of AV Synchrony Treatment of Pacemaker Syndrome

36. Goals of Choosing a Pacing Mode Desire to maintain AV synchrony Desire to maintain AV synchrony –DDD mode is best to provide AV synchrony Preservation of AV synchrony requires: Preservation of AV synchrony requires: –Viable atrium and –Patient must not have chronic/permanent atrial tachyarrhythmias

37. Optimal Pacing Mode Decision Tree Pacemaker is indicated What is the condition of the SA Node? Is the patient chronotropically incompetent? VVIR VVI Ventricular Pacing Is the patient chronotropically incompetent? DDDR DDD AV Synchrony Is AV conduction adequate? Is the patient chronotropically incompetent? Is the patient chronotropically incompetent? DDDRDDDAAIRAAI AV Synchrony YN N Y YN Y N YN Chronic atrial fibrillation unexcitable atrium Normal or sinus bradycardia

38. AV Synchrony - DDD(R) Pacemaker is indicated What is the condition of the SA node?? Is AV conduction adequate? Is the patient chronotropically incompetent? DDDRDDD N YN Normal or sinus bradycardia Benefits – AV synchrony – Normal sinus response Risks – Loss of AV conduction

39. Ventricular Pacing Pacemaker is indicated What is the condition of the SA node? Is the patient chronotropically incompetent? VVIR VVI Y N Chronic atrial fibrillation unexcitable atrium Benefits – Maintain minimum cardiac output – Single-lead implantation Risks – Loss of AV synchrony – Retrograde conduction – Increased incidence of atria arrhythmias

40. Rate Modulation/Rate Responsive Mode

41. Rate Responsiveness/Adaptive- Rate Pacing In Rate Responsive pacing (modes ending with “R”), sensor(s) in pacemaker are used to detect changes in physiologic needs and increase the pacing rate accordingly In Rate Responsive pacing (modes ending with “R”), sensor(s) in pacemaker are used to detect changes in physiologic needs and increase the pacing rate accordingly The sensor The sensor –Sensors are used to detect changes in metabolic demand –Sensors sense motion (piezoelectric crystal or accelerometer) or use a physiologic indicator, e.g., minute ventilation The algorithm The algorithm –Within the software of the pacemaker –Uses the input from the sensor to determine the appropriate paced heart rate for the activity

42. DDDR Pacing Example of Dual-Chamber Rate- Responsive pacing Example of Dual-Chamber Rate- Responsive pacing

43. DDDR A DDDR pacemaker has two or more indicators of a patient’s metabolic need: –Sinus node – the best indicator, as it is physiologic –Input from the sensor(s) within the pacemaker

44. Pacemaker Timing and Function

45. LRL LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms Lower Rate Limit

46. LRL 60 ppm VTL120 ppm AVD150 ms PVARP250 ms DDD-09 Ventricular Tachycardia Limit (Upper Rate Limit) VTL

47. AV LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms A-V Delay AVD

48. AV s p LRL 60 ppm VTL120 ppm AVp200 ms Avs150 ms Min. Adap. A-V 88 ms PVARP250 ms A-V Delay

49. AVDPVARP TARP LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms TARP450 ms Atrial Refractory Periods PVARP = Post Ventricular Activation Refractory Period TARP = Total Atrial Refractory Period TARP = AVD + PVARP

50. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-16 Atrial Refractory Periods Note: this P wave does not trigger ventricular pacing because it falls within the PVARP PVARP

51. Pacemaker Malfunctions

52. DDD-22 LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms Failure to Capture

53. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms DDD-23 Failure to Capture

54. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms TARP 450 ms DDD-02 Failure to Sense

55. LRL 60 ppm VTL120 ppm AVD150 ms PVARP350 ms DDD-12 Pacemaker Associated Heart Block

56. LRL 60 ppm VTL120 ppm AVD150 ms PVARP250 ms DDD-14 Pacemaker Associated Heart Block Note: AVD is extended to preserve the upper rate limit

57. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-15 “Pacemaker Wenkebach”

58. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-17 Pacemaker Associated Tachycardia

59. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-18 Pacemaker Associated Tachycardia

60. continuous LRL 60 ppmAVs150 ms VTL100 ppmMin. Adap. A-V 88 ms AVp200 msPVARP250 ms DDD-19

61. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-20 Oversensing

62. LRL 60 ppm VTL120 ppm AVp200 ms AVs150 ms Min. Adap. A-V 88 ms PVARP250 ms DDD-21 Oversensing with Safety Pacing

63. Is This a Pacemaker Malfunction?

64. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms DDD-08 Normal DDD Pacing

65. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms TARP450 ms DDD-01 Normal DDD Pacing

66. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms DDD-07 Normal DDD Pacing

67. LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms DDD-05 Fusion

68. DDD-04 LRL 60 ppm VTL120 ppm AVD200 ms PVARP250 ms TARP450 MS Safety Pacing

69. The End