Is coronary computed tomographic angiography the “gold standard” for coronary artery disease?

The proliferation of noninvasive diagnostic tests has been accompanied by validation of each technology by a “gold standard.” The anatomic “gold standard” of catheter angiography has been uniformly employed to validate the functional technologies of nuclear, echocardiographic and magnetic resonance stress testing and fractional flow reserve, which are then paradoxically used to judge the anatomic findings. Catheter angiography has also been used as the “gold standard” for the newest technology, coronary computed tomographic angiography (CCTA). By virtue of similar three dimensional characteristics, intravascular ultrasound may be the more appropriate standard for CCTA. However, because of the paradoxical interdependence of the validations, there can be no true “gold standard” for any technology; clinical, outcomes may ultimately be the best option. In the interim, clinical judgment and common sense should be substituted for slavish adherence to an absolute “gold standard” for diagnostic imaging and total reliance on a single diagnostic test.