Temporary cardiac pacing is used to treat acute bradyarrhythmias or tachyarrhythmias until the underlying condition resolves or permanent pacing can be initiated. It aims to re-establish normal hemodynamics compromised by abnormal heart rates. Transvenous pacing is the preferred method, involving insertion of endocardial leads through veins to the heart. Precise lead placement is important and is confirmed with imaging. Pacing parameters like threshold, rate and sensing are optimized. Complications include those related to vascular access and device malfunction requiring troubleshooting. Close monitoring is needed to ensure proper pacing and detect any issues.

1. Temporary Cardiac Pacing
Dr. Md. Mashiul Alam
Phase B resident
Chairperson: Prof. F. Rahman

2. Introduction
Temporary cardiac pacing involves electrical
cardiac stimulation to treat a bradyarrhythmia
or tachyarrhythmia until it resolves or until
long-term therapy can be initiated.
The purpose of temporary pacing is to re-
establish circulatory integrity and normal
hemodynamics that are acutely compromised
by a slow or fast heart rate.

3. Indication
 Acute hemodynamically significant bradycardia or
asystole
 Acute MI:
New bifasicular block (RBBB + LAD or RAD)
New LBBB with 1st degree AV block
Alternating LBBB and RBBB
Mobitz Type II and complete heart block ( in case
of hemodynamically significant in Inferior MI)
RVI with loss of AV synchrony

4.  Bridge to permanent pacing
 Termination of tachycardias (Overdrive pacing)
 Post cardiac surgery which may affect AV node
of His bundle
 Electrophysiological study
 Prophylactic during RHC in the setting LBBB
Complex PCI in RCA
 Drug toxicity e.g., digoxin, beta blocker

5. Relative contraindication
• Poor vascular access
• Bleeding disorder or anticoagulaiton therapy:
INR should be > 1.8
Platelete count >50,000

6. Temporary pacing methods
• Transcutaneou ventricular pacing (TCP)
• Transesophageal or transgastric pacing
• Epicardial pacing
• Transvenous pacing

7. TCP
Emergency treatment of sever bradycardia or
asystole and bridge to transvenous pacing
Lead placement:
• Anterior posterior position
One at the anterior chest wall at V3 positon
another one posteriorly below scapula
• Anterior lateral position
Over sternum and at apex

9. • Pulse width – 20 to 40 ms
• High output – 100 to 200 mA
Common problem:
Sever patient discomfort
Failure to capture

10. Transesophageal or gastric pacing
• Flexible electrode on the tip of a catheter
down the esophagus for atrial pacing
• Advanced to the fundus of stomach for
ventricular pacing
Rarely used

11. Epicardial Pacing
At the time of aortic valve replacement, AV
canal defect repair, tricuspid surgery or
Ebstein anomaly correction
Epicardial pacing wires are placed in atrium and
ventrical at the time of surgery. Fine small
caliber wire are used only for a short period.

12. Transvenous pacing
• Patient preparaton:
Infromed consent if possible ( no need in
emergency condition)
Peripheral IV access if the procedure is
elective
should be performed in monitored setting
equipped with fluoroscopy and crash cart
May be perfromed ECG or echo guided in
some situations

13. • Site
Femoral vein
Internal jugular vein
Subclavian vein
Brachial vein
Ipsilateral subclavian vein should be avoided if
permanent pacemaker is planned
Femoral approach is advisable if undergone
thrombolysis

15. Temporary leads should be resited from femoral
access sites after 48 hours and from other
sites after 5-7 days when possible to prevent
infection
• Lead choice-
Active fixation leads allows greater pacemaker
stability
Passive fixation lead – usually done

17. • Instruments
C-arm image-intensifier/ fluroscope
Temporary pacing box
5F temporary pacing wire
5F or 6F introducer sheath
External pacemaker / defibrillator
Cardiac monitor with non invasive / invasive
monitoring facilities
Oxygen and air inlet

20. • Position of the patient:
Supine in bed
Tendelenberg postion for internal jugular and
subclavian approach for filling of the vein and
prevention of air embolism

21. • Technique
- Venous sheath is inserted by Seldinger
technique
Ventricular lead insertion
Atrial lead insertion

24. Ventricular lead insertion
• Leads are straight or slightly angulated near
the tip
• Pacing catheter is advanced through venous
sheath under fluoroscopy guidance (20-30
degree LAO projection)
• Catheter advanced through tricuspid valve
and turned either clockwise or anticlock wise
to direct the tip anteriorly

25. • Attempt to cross TV directly
• If unsuccessful gentle pressure applied with
catheter torqued to allow mid portion of
catheter to prolapse across the valve or by
looping the tip against the lateral atrial wall
and rotating the loop medially
• Once catheter in the ventricle – it is rotated so
that the tip points inferiorly to the apex

26. • The ideal catheter placement site-
diaphragmatic surface or floor of the right
ventricle anywhere between the midpoint and
apex
• Placement at the Apex should be avoided as
there is increased chance of perforation
• RVOT is a option but unstable tip location

27. Ensuring accurate lead placement
Tip will be located left side of the spine in AP
view and anterior inferior postion in lateral
veiw. Some buckling is acceptable.
If tip is in coronary sinus the tip will be posterior
superiorly directed in lateral view
• Leads are attached with the pulse generator….

30. Testing
Once catheter is in a stable position , threshold
testing should be performed

32. Pacing rate: regulates the number of impulses that
can be delivered to the heart per minute. The rate
setting depends on the physiological needs of the
patient.
Threshold: is the lowest energy, which will cause the
myocardial cell to contract. The desired threshold
is 0.5-1.0mA.
Sensing is the ability of the pacemaker to “see” when a
natural (intrinsic) depolarization is occurring.
– Pacemakers sense cardiac depolarization by
measuring changes in electrical potential of
myocardial cells between the anode and cathode.
– Expressed in Millivolts (mV).

33. Setting stimulation threshold
• Set RATE at least 10 bpm above patient’s intrinsic rate.
• Decrease OUTPUT: Slowly turn OUTPUT dial counterclockwise until
ECG shows loss of capture.
• Increase OUTPUT: Slowly turn OUTPUT dial clockwise until ECG
shows consistent capture. This value is the stimulation threshold.
• Set OUTPUT to a value 2 to 3 times greater than the stimulation
threshold value.
• Restore RATE to previous value
.

34. Setting sensing threshold
• Set rate at least 10 bpm below patient’s intrinsic rate.
• Adjust output: Set OUTPUT to 0.1 mA .
• Decrease SENSITIVITY: Slowly turn MENU PARAMETER dial
counterclockwise until pace indicator flashes continuously.
• Increase SENSITIVITY: Slowly turn MENU PARAMETER dial
clockwise until sense indicator flashes and pace indicator
stops flashing. This value is the sensing threshold.
• Set SENSITIVITY to half (or less) the threshold value.

35. Post placement CXR
• To evaluate pneumothorax and proper
position of lead after the procedure

37. Pacer Care
• Check catheter insertion site daily for signs of
infection and apply regular sterile dressing at
regular interval
• Obtain daily 12 lead surface ECG with and
without pacing
• Check function daily by determining the
sensing and pacing threshold and check
underlying rhythm daily by decreasing the
pacing rate gradually

38. Complication and troubleshooting
• Related to central venous access (Hematoma,
Pneumothorax, hemothorax, air embolism,
thrombosis, arterial puncture, AV fistula,
infection)
• Cardiac arrythmia
• Myocardial perforation
echocardiogram should be performed
Lead should be withdrawn only when there is all
facilities for percardiocentesis or surgical
drainage

39. • CHB in a patent with prevous LBBB due to
irritation of right bundle while lead placement
• Pacemaker related
Generator failure – change the generator/
keep an extra generator for emergency
Ventricular non capture

40. Ventricular non capture/ capture
failure

41. • Causes of Failure to Capture:
Insufficient output
Low pacemaker battery
Displaced or fractured lead
Electrolyte abnormalities: acidosis; hypoxia;
hypokalaemia

42. • Management:
Increase output on Output dial
lead may need to be repositioned or replaced
Check electrolytes
View rhythm in different leads
Change electrodes Check connections Change
battery, cables, pacemaker box

43. Ventricular undersensing
Potential for ventricula fibrilation ( due to R on T
phenomena)

45. • Management:
Increase sensitivity (reduce mV on Sense dial)
lead may need to be repositioned or replaced
View rhythm in different leads
Change electrodes Check connections Change
cables, battery, pacemaker box Check
electrolytes

46. Ventricular oversensing
Pacing does not occur when intrinsic rhythm is
inadequate

47. • Pacemaker too sensitive
• Possible lead displacement
• Pacemaker failure
Danger of heart block, asystole

48. • Management:
Reduce sensitivity (increase mV on Sense dial)
lead may need to be repositioned or replaced
View rhythm in different leads
Change electrodes
Check connections
Change cables, battery, pacemaker box Check
electrolytes

49. Thank you
There is no alternative to practical experience….