12th Class Biology Biotechnology And Its Applications Therapeutic Instruments.

Pacemakers

(1) Pacemaker is a device that supplies electrical impulses to the heart to maintain the heartbeat at a regular rate.

(2) The artificial pacemaker was introduced by Chardack in 1960.

(3) Pacemakers are life saving when the normal heart rate 72-80 drops to abnormally low levels like \[30-40\] due to diseases.            

(4) Pacemaker consists of a pulse generator and an electrode.

(5) The pulse generator is hermetically sealed box; it contain lithium halide cells to provide power for over 10 years.

(6) The electrode is a fine metallic spring ensheathed in a thin layer of biocompatible plastic; the special tip remains in contact with the interior of right ventricle.

(7) An artificial pacemaker is implanted when a person's sinu-atrial node is not functioning properly.

(8) Two basic types of pacemakers are fixed-rate and demand type.

(9) Fixed-rate pacemaker discharges impulses at a steady rate, irrespective of the heart's activity.

(10) Demand pace maker discharges impulses only when the heart-rate slows or a beat is missed. A normal heart-rate and beat suppresses the pacemaker.           

(11) A pacemaker may be external (worn on belt) or internal (implanted in the chest).

(12) There are two main types of implantation, transvenous implantation and epicardial implantation.

(13) Modern pacemakers are comparatively insensitive to interference, but may be affected by powerful electromagnetic pulses.

(14) Anyone fitted with a pacemaker should avoid powerful radio or radar transmitters and should not pass through security screens at airports.

(15) Pacemakers are likely to be influenced by microwave ovens, electric shavers, automobile ignition and cellular phones.