DICOM PS3.3 2021e - Information Object Definitions
A.34.3.4.2 Acquisition Context Module

For SOP Instances of ECG acquired in the cardiac catheterization lab, the Defined TID for Acquisition Context Sequence (0040,0555) is TID 3403 “Catheterization Acquisition Context”. For routine resting or stress ECG, the Defined TID for Acquisition Context Sequence (0040,0555) is TID 3401 “ECG Acquisition Context”.

DICOM PS3.3 2021e - Information Object Definitions