A system and method for reducing image noise and artifacts in coronary computed tomography angiography includes acquisition of CT images at multiplicity of CT slices arranged in such a fashion throughout the phases of the cardiac cycle as to utilize the majority of the X-ray radiation to which the myocardium exposed during the cycle. The acquired imaging data is processed with the use of a TAF filter to reduce the amount of noise and artifacts associated with the CT's system operating at low tube current. The TAF filter is configured to adapt the filtering strength in time domain according to temporal variations of the same anatomical location as identified in its corresponding CT slices.