A. Channel Source

The Defined Context ID for the Channel Source Sequence (003A,0208) in each Channel Definition Sequence Item shall be CID 3011. The Channel Source Code Value shall encode at minimum the anatomic location of the channel source.

The Channel Source Modifiers Sequence (003A,0209) in each Channel Definition Sequence Item shall be used to specify additional qualifiers of the semantics of the waveform source, including metric (measured physical quality), function (measurement or stimulus), and technique from Defined Context ID 3240, and anatomic location qualifiers from Defined Context ID 3019, if not encoded by the Channel Source Code Value. If not explicitly encoded, the default metric and function shall be “voltage measurement”. If a differential signal is used, that shall be indicated in a Modifier Item, and the positive pole and negative pole identified in the subsequent two modifiers.

Notes: 1. Terms from other Context Groups may also be used for extended specification of the Channel Source, as declared in the Conformance Statement for an application (see PS3.2).

2. A differential signal from the high right atrium , where electrode 1 on the catheter is the positive pole and electrode 3 the negative pole, could be specified by coded terms meaning: Channel Source: “High Right Atrium” Channel Source Modifiers: “Differential”, “E1”, “E3” (Implicit default modifier: “Voltage Measurement”)