C.7.6.18.1 Cardiac Synchronization Module

Table C.7.6.18-1 specifies the attributes of the Cardiac Synchronization Module.

Table C.7.6.18-1 CARDIAC SYNCHRONIZATION MODULE ATTRIBUTES

Attribute Name Tag Type Attribute Description
Cardiac Synchronization Technique (0018,9037) 1C Defines if a cardiac synchronization technique was applied during or after the acquisition. Enumerated Values: NONE REALTIME = total time for the acquisition is shorter than cardiac cycle, no gating is applied PROSPECTIVE = certain thresholds have been set for a gating window that defines the acceptance of measurement data during the acquisition RETROSPECTIVE = certain thresholds have been set for a gating window that defines the acceptance of measurement data after the acquisition PACED = there is a constant RR interval (e.g., Pacemaker), which makes thresholding not required Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED. May be present otherwise.
Cardiac Signal Source (0018,9085) 1C Cardiac Signal Source. Defined Terms: ECG = electrocardiogram VCG = vector cardiogram PP = peripheral pulse MR = magnetic resonance, i.e. M-mode or cardiac navigator Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals other than NONE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals other than NONE.
Cardiac RR Interval Specified (0018,9070) 1C R-R interval in ms measured prior to or during the scan. Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals other than NONE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals other than NONE. Note: The Heart Rate (0018,1088) attribute is not used in this Module, since its value can be derived as 1/ Cardiac RR Interval Specified (0018,9070).
Cardiac Beat Rejection Technique (0018,9169) 1C Cardiac arrhythmia rejection technique. Defined Terms: NONE RR_INTERVAL = rejection based on deviation from average RR interval QRS_LOOP = rejection based on deviation from regular QRS loop PVC = rejection based on PVC criteria Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE.
Low R-R Value (0018,1081) 2C R-R interval low limit for beat rejection, in ms. Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE.
High R-R Value (0018,1082) 2C R-R interval high limit for beat rejection, in ms. Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals PROSPECTIVE or RETROSPECTIVE.
Intervals Acquired (0018,1083) 2C Number of R-R intervals acquired and used to create the image (not including the intervals rejected). Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals other than NONE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals other than NONE.
Intervals Rejected (0018,1084) 2C Number of R-R intervals rejected. Required if Image Type (0008,0008) Value 1 is ORIGINAL or MIXED and Cardiac Synchronization Technique (0018,9037) equals other than NONE. Otherwise may be present if Image Type (0008,0008) Value 1 is DERIVED and Cardiac Synchronization Technique (0018,9037) equals other than NONE.
Skip Beats (0018,1086) 3 Number of beats prescribed to be skipped after each detected arrhythmia.
Cardiac Framing Type (0018,1064) 1C Description of type of framing performed. See C.7.6.18.1.1.1 for description and Defined Terms. Required if type of framing is not time forward from trigger, may be present otherwise.

Note: Low R-R Value (0018,1081), High R-R Value (0018,1082), Intervals Acquired (0018,1083) and Intervals Rejected (0018,1084) in this Module apply to the entire Image. The Cardiac Gating Sequence (0018,9118) in the Cardiac Gating Functional Group uses the same attributes and specifies the values for a single frame.

C.7.6.18.1.1 Attribute Descriptions

C.7.6.18.1.1.1 Cardiac Framing Type

Cardiac Framing Type (0018,1064) is the mechanism used to select the data acquired to construct the frames within a specified cardiac timing interval.

Defined Terms:

FORW = time forward from trigger

BACK = time back before trigger

PCNT = percentage of R-R forward from trigger