(CTA) A computed tomographic angiography or computerized tomography angiogram is a diagnostic imaging test that combines conventional CT technique with that of traditional angiography to create images of the blood vessels in the body - from brain vessels to arteries of the lungs, kidneys, arms and legs.
High resolution CT scans with thin slices and intravenous injection of iodinated contrast material provide detailed images of vascular anatomy and the adjacent bony structures. CTA requires rapid scanning as the imaging data are typically acquired during the first pass of a bolus of contrast medium. The selection of acquisition timing is important to optimize the contrast enhancement, which is dependent on contrast injection methods, imaging techniques and patient variations in weight, age and health. CT angiography is less invasive compared to conventional angiography and the data can be rendered in three dimensions.

CTA techniques are commonly used to:
See also Cardiovascular Imaging, Magnetic Resonance Angiography MRA, Coronary Angiogram, Computed Tomography Dose Index and Computed or Computerized Axial Tomography.

(CCTA) Coronary computed tomography angiography is a diagnostic imaging procedure to visualize the coronary arteries. CCTA is a non-invasive angiogram that allows the assessment of narrowed and clogged arteries that can cause heart attack and stroke.
Coronary CTA is a non-invasive alternative to traditional angiography that offers detailed images of heart function, resulting in faster, more accurate diagnosis. It helps stratify cardiac risk in patients with low to intermediate likelihood of coronary artery disease. For some patients with chest pain, coronary CTA can rule out the need for cardiac catheterization.
Coronary imaging requires a very fast CT scan, because the coronary arteries and other cardiac structures move rapidly during the cardiac cycle. The current 'state of the art' 64 slice multi-detector row CT systems rotate around the patient in less than 500 ms. The data must be acquired monitored by an electrocardiogram, which allows the computer to reconstruct retrospectively slices at different small segments of the cardiac cycle. This cardiac synchronization reduces motion artifacts in the coronary arteries and provides movies of the beating heart and valve motion.
See also Coronary Angiogram, Calcium Score, Cardiac Phase, Cine Mode and Defibrillator.