What is an Artificial Cardiac Pacemaker?

not to be confused with the heart's natural pacemaker!!!

Rounak Patra

13MS106

Understanding heart's electrical system

Sinus node, the natural pacemaker of heart.

History of Pacemaker

1932 Albert Hyman Concept of artificial pacemaker, magneto-generator to power

up electrode.

1950 John Hopps 1st transcutaneous pacemaker.

Vaccum tube technology and direct AC power supply is used.

1958 Earl Bakken 1st wearable transistorized pacemaker.

1958, 8th

October

Dr. Ake Senning

Dr. Rune Elmquist

1st implanted (trans-venous) pacemaker.

1959 W.M. Chardack

Wilson Greatbatch

1st successful long term implantable pacemaker.

1970 Introduction of Li-Iodide battery technology.

1980 Introduction of rate responsive pacing.

History of Pacemaker

Arne Larsson (1915–2001) became the

first to receive an implantable pacemaker

(1958). He had a total of 26 devices

during his life.

Who needs it!!

“Abnormal Heart Rhythm”

(Indications for Pacing)

Sinus Node Dysfunction

Sinus bradycardia

Sinus arrest

SA block

Brady-tachy syndrome

Chronotropic incompetence

(CI)

AV Block

• First-degree AV block

• Second-degree AV block(Mobitz types I and II)

• Third-degree AV block

Bundle Branch Block

Device construction and materials

A Pacemaker System consists of a

• Pulse Generator & Power Source

• Pacing Leads or wires

The Pulse Generator

Circuit

Battery

Pacing Lead Systems

Unipolar Pacing System Bipolar Pacing System

Cathode (-)

Type based terminologies1. Asynchronous/Fixed Rate

• It delivers an electrical impulse at a present fixed rate to the heart.

• Occurs in non-sensing modes.

• Functions independently of cardiac activity.

• The pulse generator delivers artificial stimulus only when intrinsic pacemaker fails to function (at a predetermined rate).

• Does not compete with patient’s rhythm.

2. Synchronous/Demand

Single-Chamber System

• The pacing lead is implanted

either in the atrium or

ventricle, depending on the

chamber to be paced and

sensed.

• Single ventricular lead does not

provide AV synchrony.

• One lead implanted in the

atrium.

• One lead implanted in the

ventricle.

• Provide AV synchrony.

• Atrio-ventricular (AV)

Sequential (Dual Chamber)

provide sufficient AV delay

to permit adequate

ventricular filling.

Dual-Chamber System

Rate responsive pacing

When the need for oxygenated blood increases,

the pacemaker ensures that the heart rate

increases to provide additional cardiac output.

THE NBG CODE

By Berkovits, June 1964

An Example of Basic demand pacemaker Circuit

Recent advances in pacemaker technology

• MRI-compatible pacemaker called the Revo MRI SureScan.(Also

prevent damage from radio waves and magnet)

• Upgrade in Rate Responsive modes: Dynamic AV delay feature

that automatically adjusts on a cycle-by-cycle basis to mimic

physiologic response.

• Leadless pacemaker: Nanostim, 10 times smaller than the

conventional pacemaker which can be repositioned easily (devoid

of lead failure etc.) and quality of the life for patient is

significantly improved due to no restrictions of activity.

ADVERSE EFFECTS

1. Pacemaker syndrome

2. Infection

3. Venous thrombosis

4. Air embolism and Hematoma

5. Lead dislodgement and Perforation via

pacemaker lead.

6. Pneumothorax

• The Evolution of Pacemakers by Sandro A.P. Haddad, Richard P.M.

Houben, And Wouter A. Serdijn.

• Guyton and Hall Textbook of Medical Physiology 12th Edition.

• http://www.pacemaker.vuurwerk.nl/info/nbg_code__naspe.htm

• Recent advances in pacemaker and implantable defibrillator therapy

for young patients. Walsh EP, Cecchin F.

• Basic Principles of Cardiac Pacemaker Technology- Springer.

• Pulse Output by Michael K. Laudon

• Pacemaker Overview by Stuart Allen.

• https://www.nhlbi.nih.gov/health/health-topics/topics/pace

• https://en.wikipedia.org/wiki/Artificial_cardiac_pacemaker

References