This document discusses pacemakers, including their history, components, types, functions, programming, complications, and clinical management. It provides details on pacemaker technology, how they treat arrhythmias, and considerations for patients with pacemakers during medical procedures or surgery.

4. Pace maker is a device that applies electric
impulses to the Rt. atrium or the Rt. Ventricle or
both to treat various electrophysiological disorders
related to conduction and arrhythmia of the heart.

5. In 1950 the initial pacing system was
consisted of a single lead asynchronous pace maker,
which paced the heart at a fixed rate.
Over the years with advanced technology,
pacemakers are currently more sophisticated, with
the availability of a multi programmable devices, and
Automated Implantable Cardioverter Defibrillators
(AICD) designed to treat fatal tachyarrythmias.

7. Pulse Generator: It includes
Energy source and electric circuits for pacing and
sensory function.
Leads:
Insulated wires connecting the pulse generator.
Electrode:
It is an exposed metal end of the lead in contact
with:
Endocardium; Endocardial Pacing
Epicardium; Epicardial Pacing

8. Unipolar Pacing:
Cathode or active lead stimulates the heart and
returns to anode on the casing of pulse generator via
the myocardium and adjacent tissue to complete the
circuit.
Bipolar Leads:
Two separate electrodes located within the paced
chamber.
The possibility of extraneous
noise

9. R Wave Sensitivity:
It is the measure of minimal voltage of intrinsic
R wave, necessary to activate the sensing circuit of
the pulse generator and thus inhibit or trigger the
pacing circuit.
It is about 3mV on an
external pulse
generator will Maintain

11. I II III IV V
Pacing Sensing Response Programmability Tachycardia
AICD
O-None O-None O-None O-None O-None
A-Atrium A-Atrium I-Inhibited C-Communicating P-Pacing
V-Ventricle V-Ventricle T-Triggered P-simple S-Shocks
programmable
D-Dual D-Dual D-Dual M-multi D-Dual
(A+V) (A+V) (I+T) programmable (P+S)
S-Simple S-Simple R-Rate
(A or V) (A or V) modulation

15. Dual Chamber AV Sequential Pacing
(DDD, DVI, DDI, and VDD)
Unipolar or bipolar leads are used, for the right atrial
appendage and right ventricular apex.
Atrium is stimulated first to contract, then after an
adjustable PR interval ventricle is stimulated to contract.
Uses:
Indicated in AV block, carotid sinus syncope, and sinus
node disease.

16. Advantages:
- Preserve the normal AV contraction sequence.
- Beneficial when atrial contraction is important for
- ventricular filling (e.g. aortic stenosis.)
Disadvantage:
Pacemaker-mediated tachycardia (PMT)
Back conduction from the ventricle to the atrium is
sensed by the atrial circuit, and triggers a ventricular
depolarization leading to PMT.
Overcome by carful adjustment PR

17. It provides flexibility to correct abnormal device behavior.
It adapts the device to patient’s specific and changing needs.
Programmable Factors:
- Pacing rate. - Hysteresis
- Pulse duration. It is the difference between
- Voltage output. intrinsic heart rate at which
- R wave sensitivity. pacing begins (60 beats/min)
- Refractory periods. and pacing rate (e.g.72
- PR interval. beats/min).
- Mode of pacing. It is useful in
- Atrial tracking rate. patients with sick
sinus syndrome.

18. Pacemakers, which not only sense the atrial or ventricular
activity but also sense various other stimuli and thus,
increase the pacemaker rate.
Common sensors used in clinical practice:
- Vibration. - QT interval.
- Acceleration. - Preejection period.
- Minute ventilation. - Rt.V. SV, & contractility.
- Respiratory rate and depth. - Mixed venous oxygen
- CVP. saturation.
- CV pH. - Right atrial pressure.

19. A variety of clinical signs and symptoms resulting
from deleterious haemodynamics induced by
ventricular pacing.
Intact retrograde VA conduction
Pathophysiology: Asynchronous with atrial rate
loss of atrial systole
“kicks”
In Patient who can’t compensate by
Reduction in COP Activation of baroreceptor reflex that
Coronary blood flow increase peripheral resistance to maintain
Coronary resistance systemic blood pressure

20. Incidence:
Retrograde VA conduction is present in about;
- 15% of patients with complete antegrade AV block.
- 67% of patients with intact antegrade AV
- conduction paced for sinus node disease.
Onset:
May be acute to chronic.

21. Clinical signs and symptoms:
- Hypotension. - Syncope. - Vertigo.
- Headedness. - Fatigue. - Dyspnoea.
- Cough. - CHF.
- Awareness of beat-to-beat variation of cardiac
response from spontaneous to paced beats.
- Neck pulsation or pressure sensation in the chest,
neck, or head, headache.
- Chest pain: loss of atrial kick, increases coronary
- resistance and decreases coronary blood flow.

22. Acceleration in paced rates due to aging of the
pacemaker or damage produced by leakage of the
tissue fluids into the pulse generator.
Treatment:
- Change the pacemaker to an asynchronous mode.
- Reprogram it to a lower outputs.
- Changing of pulse generator if patient was
hemodynamically unstable.
Treatment with
antiarrhythmic drugs or

23. I - Evaluation of the Patient.
II- Evaluation of the pace maker.

24.  Evaluation of severity cardiac disease, & its
current functional status responsible for the
insertion of pacemaker.
 Associated medical problems:
“CAD, DM, HTN, & CHF”
 Concurrent medical treatments.
 Preimplantation symptoms:
Light headedness
Dizziness even after pace maker
Fainting. insertion ……. Why?

26.  Type of pacemaker “fixed or demand rate.”
 Time since it was implanted.
 Rate pacemaker at the time of implantation.
 Half life of the pacemaker battery.
10% decrease in the rate from the time
of implantation indicates power source depletion.
These information can be taken from the
manufacture’s book kept with the patient

29. It is important, to consider the location of an
operative procedure in relation to:
• The site of the plus generator.
• When a sensor for rate modulation is in use.
In our case plus generator is

30. Inappropriatel
y
inhibit
or
trigger
stimulation

31. Direct interference Indirect interference
- MRI. - Orthopedic saw.
- Surgical electrocautery. - Telemetric devices.
- Dental pulp vitality tester.
- Mechanical ventilators.
- Lithotriptors.
- Cellular telephones.,

35. Defibrillation Stimulation
loss of
threshold
capture

36. - Positive pressure ventilation.
- Nitrous oxide entrapment in the pacemaker
pocket.
- Insertion of pulmonary artery or central venous
catheter.
Only multipurpose PA catheter with pacing
facilities can also be used when highly indicated

37. The minimum amount of energy required to
consistently cause depolarization and contraction
of the heart.
It is measured in terms of:
- Amplitude: programmed in volts or in milliampers.
- Duration: measured in milliseconds.

38. - 1-4 weeks after implantation.
- Myocardial ischemia / infection.
- Hypothermia, Hypoxia, & Hypothyroidism.
- Hyperkalaemia.
- Acidosis/Alkalosis.
- Antiarrythmics (class Ic,3, IA/B,2).
- Severe hypoxia.
- Hypoglycemia.
- Local Anesthetic drugs.
- The use of Defibrillator.

39. - Increased catecholamines.
- Stress, & anxiety.
- Sympathomimetics drugs.
- Anticholinergics.
- Glucocorticoides.
- Hyperthyroidism.
- Hyper metabolic status.

41. MR: 1002067625
Name: Samel Mahal Sayer
Date of birth: 9/5/1948
Date of admission: 13/12/12
CCU: bed 5

42. A known diabetic, HTN. Pt. presented to ER on
13/12/12 Pt complaining of un relieved chest pain
for the last 24 hr.
His ECG showed Q waves in leads II, & AVF
Patient was diagnosed as acute inferior MI.
Pt. received Aspirin, Plavix and was admitted to the
CCU, during which he suffered complete heart block
necessitated insertion of trans femoral pace maker
with the following setting: Rate: 70/min., mV: 2, IVV.
Blood pressure was 110/68

46. Na K Urea Creat. Glucose
136 3.9 5.2 63 10
Hb HCT Plat
15 43.3 157
Other investigations regarding liver
function, coagulation profile were within normal.

47. - Shortness of breath, & orthopnic
- Recent non inflammatory productive cough
- on top of restricted lung disease.
- Auscultation: revealed rhonchi and wheezy chest.
As Pt was booked for emergency CABG, and
AVR pulmonary function tests were not available

50. - Myoclonic movements of Etomidate and
ketamine
should be avoided in vibration rate responsive PM.
- Even though, inhibition of myoclonic movements
by priming dose of NDMR, and Dormicum can
solve this problem in such PM.

52. Owing to close proximity of the pericardium to the
myocardium non pacing electric signals of the
unipolar surgical cautery coming from all directions
inhibited the pacemaker pacing signals of the plus
generator.
In addition, electric signals of the cautery resulted in
fatal arrhythmias in absent of internal AV conduction
or external pacing of the ventricle.

55. coronary
Resistance
coronary
Perfusion,
Un favor &blood flow
Aortic
Stenosis

56. A clinical prove that retrograde
VA conduction was going on

57. Under the effective management of adrenaline BP
was raised to 130/70.
At this good per fusing BP ischemia of Av node and
conducting system was decreased, resulted in a good
intrinsic conduction with an R wave > 2 mV thus
pacing was inhibited.
This was a considerable
prognostic singe
Unfortunately such BP could not be maintained for

58. It happened during prepartion for great vessels
cannulation and elevation of the LL for dressing
venous grafting site.
Dislodgment of electrodes
form its site of insertion
A gentle tap on the Rt. Ventricle
was able to retune pacing to the heart.

62. Placing temporary
transcutaneous
electrodes in the left
shoulder area anteriorly
connected to a temporary
pacemaker generator.

63. Two additional pacemaker
electrodes are placed
cutaneously on the
posterior wall of the chest and
connected to a second
temporary pacemaker
generator.

64. Increasing the rate of the temporary extra cardiac
tissue pacemaker above that of the permanent
cardiac pacemaker, results in;
Inhibition of permanent demand activity.