For more than a quarter of a century, investigators have examined the feasibility of acquiring functional cardiac information using contrast-enhanced computed tomography (CT). Early experimental studies and small clinical series suggested that myocardial perfusion abnormalities could be identified with CT.1"9 Quantification of left ventricular ejection fraction (LVEF) and detection of wall motion abnormalities was initially limited by the suboptimal temporal resolution of single-detector systems. Electron-beam CT allowed for greatly improved temporal resolution but, for a variety of reasons, such systems never gained a substantial foothold in clinical practice. Multidetector CT (MDCT) also offers improved spatial and temporal resolution over single-detector systems, allowing for the assessment of functional information.
The widespread deployment of MDCT systems in hospitals and imaging centers has fueled a resurgence in investigations into cardiac CT imaging, with particular attention given to noninvasive imaging of the coronary arteries. The use of this application is expected to grow considerably in the coming years. This development has led investigators to explore the means of obtaining functional information from studies that are primarily optimized for the detection of coronary artery disease. In this way, a comprehensive cardiac evaluation can be provided for patients without exposing the patient to additional radiation.