Imp PPT on PACEMAKER

1. Pacemaker
Prepared by,
Asso Prof.Mr.Vijayreddy Vandali
Med Surg Nursing Dept.

3. DEFINITION
A pacemaker is a battery
operated generator that
initiates & controls electrical
stimulation of the heart via an
electrode that is usually in
direct contact with the
myocardium.

4. PACING METHODS
Temporary Pacing:- The pulse
generator is external & the pacing
electrode is inserted by
transvenous, transthroracic,
transesophageal, or transctaneous
route either at the bedside or
under fluoroscopy.

5. CONTD…….
The transvenous route, which is
preferred in emergency
situations, requires a hard tipped
or balloon- tipped pacing lead to
be guided into the right heart &
into contact with the
endocardium.

6. Temporary transvenous pacing wire in right
ventricle inserted through antecubital vein.

7. Transvenous installation of a permanent
pacemaker. For dual-chamber pacing, a separate
pacing wire would be in the Antrim.

8. CONTD…….
The transthroracic route is most
invasive requiring attachment of an
epicardial pacing lead during open heart
surgery. In infants needing emergency
ventricular pacing, the transesophageal
route is favored. Both transcutaneous &
transesophageal pacing are preferable
in the presence of coagulation
abnormalities or venous access
difficulties.

9. PERMANENT PACING

10. PERMANENT PACING
In an operating room, the pulse
generator- a small hermetically sealed,
lithium battery weighing from 30 to 130
gm- is placed into a small tunnel
burrowed within the subcutaneous
tissue below the right clavicle (less
frequently the left clavicle). The pacing
electrode is inserted via a transvenous
route(most common) or directly applied
to the epicardial surface by
thoracotomy.

12. PACEMAKER
CLASSIFICATION
 The Inter Society Commission For Heart
Disease (ICHD) established a code to create
uniform descriptions of pacemaker function.
1st Letter:-
 indicates which chamber is paced:
V :- Ventricles
A :- Atrium
D :- Dual (Both atrium and ventricle)

14. 2nd Letter
Indicates which chamber is sensed
 V :- Ventricles
 A :- Atrium
 D :- Dual (Both atrium & ventricle)
 O :- No sensing.

15. 3rd Letter Indicates the mode (how the pacemaker
responds to intrinsic heart pulses) :
 I :- Inhibited response.
 T :- Trigger response.
 D :- Dual response – inhibited for some sensed
impulses & trigger for others.
 R :- Reverse – pacer is activated to send out
impulses during fast intrinsic heart rates
instead of slow.
 O :- No response to sensed impulses.

16. 4TH LETTER
Indicates programmable function:
 P :- Programmable (rate/ output).
 M ;- Multiprogrammable (3 or more
functions).
 C :- Multiprogrammable with
telemetry.
 O :- None.

17. 5TH LETTER
Indicates special
tachycardia function :
 B :- Bursts.
 N :- Normal rate
competition.
 S :- Scanning.
 E :- External

18. Examples of temporary pulse generators. (A, B)
Single-chamber pulse generators. (C, D) Dual-
chamber pulse generators.

19. PACEMAKER FUNCTION
 The cardiac cycle normally
begins with the clients own beat.
The pacemaker’s sensor senses
whether the intrinsic beat has
occurred, if not, the pacer sends
out an impulse to begin
myocardial depolarization

20. CONTD…..
The impulse generator is
said to “Capture” the
myocardium & there by
maintain heart rhythm.

21. PACING LEADS

22. PACING LEADS
Unipolar Pacemaker:-
Lead has only one electrode that contacts
the heart at its tip (+) pole. The power
source is the (-) pole. Patient serves as the
grounding source. Patient’s body fluids
provide the return pathway for the
electrical
signal Electromagnetic interference occurs

24. BIPOLAR LEADS
If bipolar, there are two wires to the heart
or
one wire with two electrodes at its tip.
Provides a built-in ground lead Circuit is
completed within the heart Provides more
contact with the endocardium; needs
lower
current to Pace Less chance for cautery

25. Bipolar pacing system.

27. PACING MODES

28. PACING MODES
There are essentially five
pacemaker modes involving
“single chamber pacing,”
either Atrial or ventricular,
& “dual chamber pacing”,
both Atrial & ventricular.

29. 1) FIXED RATE (AOO, VOO,
DOO)
 In fixed rate pacing, the heart is
stimulated at a continuous preset
rate independent of it’s intrinsic
electrical activity (non sensing).
 The major disadvantages is that
competition between the paced
beats & the patients intrinsic rhythm
may occur, potentiating ventricular
tachycardia & fibrillation.

30. 2) NONCOMPETITIVE (DEMAND)
PACING (VVI, VVT, AAI, AAT)
The demand pacemaker avoids
competitive beating by sensing the
electrical signals from the chamber it
is pacing (either Atrial or
ventricular). Demand pacing is either
“inhibited” or “triggered”.

31. CONTD…..
 If the spontaneous P wave or QRS
complex fails to occur, the
pacemaker discharges at its preset
delay interval.
In triggered demand pacing, the
sensing of spontaneous Atrial or
ventricular activity results in
generation of an output pulse by the
pacemaker.

32. CONTD…..
The pacemaker “fires” into the P
wave or QRS but dose not stimulate
depolarization because of myocardial
refractoriness at this time.
If no intrinsic depolarization's occurs,
the pacemaker will fire at it’s preset
delay interval.

33. A) ATRIAL DEMAND PACING
The atrium is paced & the ventricle is
allowed to be depolarized via conduction
of the paced Atrial impulse through the
normal pathway of the A-V Node & the
His- Purkinje conduction system. Atrial
demand pacing is useful in symptomatic
sinus bradycardia of any kind (provided A-
V conduction is intact)

34. B) VENTRICULAR DEMAND PACING
Patients with episodic A-V Block may
benefit from ventricular demand pacing.
When spontaneous ventricular
depolarization's fall below the preset
pacemaker rate, paced ventricular
depolarization's ensure.
Disadvantage is the loss of Atrial
ventricular synchrony & the Atrial kick.

35. 3) SYNCHRONOUS PACING (VAT, VDD)
Synchronous pacing was the first mode
developed to offer dual chamber pacing.
Sensing occurs in both atrium &
ventricle. When a P wave is sensed, a
ventricular output pulse is triggered after
a preset ateroventricular interval. If a
spontaneous QRS complex is sensed, the
paced output is inhibited, thus
preventing competitive pacing in the
ventricle.

36. 4)
ATRIOVENTRICULAR(AV
) SEQUENTIAL PACING
(DVI)
In this mode sensing occurs only in
the ventricle while pacing occurs
sequentially in the atrium & after a
preset A V interval, in the ventricle.
If spontaneous ventricular
depolarization follows quickly enough
after the paced Atrial beat,
inhibition of the ventricular output
pulse occurs.

37. DVI PACING

38. 5) UNIVERSAL ATRIOVENTRICULAR PACING
(DDD)
If spontaneous Atrial activity does not take
place within the preset time limit, Atrial
pacing triggered.
Any sensed intrinsic Atrial activity inhibits
the paced Atrial pulse.
 if ventricular depolarization in response to a
spontaneous or paced Atrial beat does not
occurs within a preset interval, a ventricular
stimulus is issued by the pacemaker.

39. CONTD…..
Intrinsic ventricular activity occurring
with in the preset time interval inhibits
the paced ventricular stimulus.
This pacing is indicated in Atrial Brady
arrhythmia with or without abnormal AV
conduction or in normal sinus node
function with AV block.

40. BENEFITS OF DDD MODE
It allows the Atrial
kick(increasing cardiac
output by 30 %).
It adjust heart rate to meet
the metabolic demands of
the body (only if sinus node
function is normal).

41. ECG

42. COMPLICATIONS
Thrmobhlebitis
Arrhythmias
Pneumothorax
Myocardial perforation
Diaphragmatic stimulation

43. HEALTH EDUCATION
WOUND CARE
PACEMAKER MANAGEMENT
ACTIVITY LEVELS
MEDICATIONS
IDENTIFICATION
FOLLOW UP CARE

44. THANK YOU