What do the first three letters of the pacemaker code represent?
There are five letters to the complete pacemaker code of which only the first three are commonly used. The first letter represents the cardiac chamber paced (A for atrium, V for ventricle, D for dual). The second letter represents the chamber sensed (A for atrium, V for ventricle, D for Dual, and O for none). The third letter represents the mode of the pacemaker, which could be described as the response of the pacemaker to the chamber it senses (I for inhibited, T for triggered, D for dual, O for none). The fourth letter indicates program-mability and the fifth letter indicates anti-dysrhythmia functions. Codes for commonly used pacemakers are listed in Table 9.1.