Cardiac CT

Cardiac CT is done in mid diastole assisted by synchronous ECG gating. The least cardiac motion occurs during diastole when the ventricles are passively filling. Prospective ECG triggering uses the ECG signal to control scanning so that X-rays are generated and projection data are acquired only during cardiac diastole.

Cardiac CT is done in CAD and for coronary calcium scoring. Coronary calcium scoring denotes the degree of atherosclerosis and determines prognosis in patients with coronary artery disease.

It is an example of multi-slice CT or multidetector CT (MDCT). In MDCT multiple sections can be taken in one rotation. Spiral CT takes only one section in one rotation.


The structure marked in the above CT image is the left ventricle.



Transverse CT images are to be observed from the foot end of the supine patient, as if we are sitting at the patient's feet. So the right-hand side of the observer corresponds to the left-hand side in the CT.

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