The demand for non-invasive diagnostic imaging in cardiology increases with the advancing age of the population. Whilst exercise testing and myocardial perfusion scintigraphy have provided non-invasive functional assessment of coronary artery disease there has been little alternative to invasive coronary angiography for anatomical assessment of the coronary tree. In recent years technological advances have enabled improvements in both temporal and spatial resolution such that multi-detector computed tomography (MDCT) is now able to reproducibly evaluate cardiac disease. The combination of this improved resolution with more advanced post-processing techniques now means that MDCT has the ability to perform both anatomical and functional assessment from a single study. This technique, therefore, not only provides a non-invasive alternative to conventional angiography but the same dataset allows concurrent assessment of cardiac function, assessment of aberrant vessels, graft patency studies and assessment of the coronary artery wall.
Cardiac CT has the potential to provide a much more complete assessment than conventional coronary angiography. It is likely to become the non-invasive imaging modality of choice to exclude significant coronary artery disease in those with intermediate risk of coronary artery disease.
This first part of a two-part article considers ECG-gated image reconstruction, image resolution, radiation dose, and post-processing protocols and limitations. The second part considers clinical applications and future developments.
