What are the key aspects of this performance measure?
Several key aspects of this performance measure deserve to be highlighted. To optimize our opportunity to improve care, we focused on elective PCIs that occur in nonacute settings, inasmuch as analyses of PCIs performed in acute settings have shown that the vast majority of these procedures are classified as appropriate according to AUC.19 In addition, even though we aimed to harmonize the document with recently published guidelines and AUC, this performance measure is not completely superimposable on their definitions for 2 reasons. First, it is acknowledged that the AUC cannot possibly include every conceivable patient presentation of appropriateness. The AUC are created via a modified Delphi approach, in which experts reach consensus after being presented with specific clinical scenarios that focus on coronary anatomy, symptoms, current medical therapy, and noninvasive studies. Thus, subtle differences between the AUC and guidelines do exist, particularly for PCI.