1. CARDIAC PACEMAKER • A cardiac pacemaker is an electric stimulator that produces electric pulses that are conducted to electrodes normally located within the lining of the heart (the endocardium). • The stimulus conducted to the heart causes it to contract – this effect can be used prosthetically in disease states in which the heart is not stimulated at a proper rate on its own (heart block). • Cardiac pacemakers are either of the unipolar or the bipolar type. • Unipolar type – a single electrode is in contact with the heart, and the negative-going pulses are connected to it from the generator. • Bipolar type – two electrodes are placed within the heart, and the stimulus is applied across theses electrodes.

2. CARDIAC PACEMAKER • PARTS • Bundle Branches • Purkinje Fibers • Electrode Terminal (Front) • Electrode Terminal (Rear) • Electrode Tip • Heart • Pacemaker (Pulse Generator) • Subclavian Vein

3. CARDIAC PACEMAKER • Asynchronous pacemaker It is the first type of pacemaker that was developed. A cardiac pacemaker that is free running. It gives a fixed heart rate. BLOCK DIAGRAM

4. CARDIAC PACEMAKER • Synchronous pacemaker It is used when a human’s heart can establish a normal cardiac rhythm between periods of block. This means that it is not necessary to stimulates the ventricles continuously. There are two general forms of synchronous pacemakers: the demand pacemaker and the arial-synchronous pacemaker.

5. CARDIAC PACEMAKER • Synchronous pacemaker The demand-type pacemaker BLOCK DIAGRAM

6. CARDIAC PACEMAKER • Synchronous pacemaker The artial-synchronous pacemaker BLOCK DIAGRAM