Operating instructions

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HeartView CT
Cardiac Scanning
Cardiac Cycle and ECG
The heart contracts when pumping blood and rests
when receiving blood. This activity and lack of activity
from a cardiac cycle can be illustrated by an Electrocar-
diograph (ECG).
To minimize motion artifacts in cardiac images, two
requirements are mandatory for a CT system:
• Fast gantry rotation to minimize the time it takes to
acquire the necessary scan data to reconstruct an
image.
• Prospective triggering of image acquisition in a
sequential mode or retrospective gating of image
reconstruction in a spiral mode based on the ECG
recording in order to obtain images during the dias-
tolic phase when the least amount of cardiac motion
occurs.
Ventricular Contraction
Systolic phase
Ventricular
relaxation
Atrial contraction
Diagnostic phase