pacing code


pacing code

A code of three to five letters used for describing pacemaker type and function. The first letter indicates the chamber or chambers paced: V for ventricle, A for atrium, or D for dual, i.e., for pacing of both chambers. The second letter, which may also be V, A, or D, indicates the chamber from which electrical activity is sensed. The third letter indicates the response to the sensed electrical activity: O indicates no response to the electrical activity sensed; I, inhibition of the pacing action; T, triggering of the pacemaker function; and D, that a dual response of spontaneous atrial and ventricular activity will inhibit atrial and ventricular pacing. The fourth letter, previously used to describe programmable functions, is now used to designate variability of the pace rate with metabolic need. A fifth letter may indicate antitachycardia-pacing capability, but this is more usually incorporated into automatic implantable defibrillators. See: pacemaker; artificial cardiac pacemakerSee also: code