In response to the rapid rise of coronary angiography and angioplasty in the 1980s, the American College of Cardiology (ACC) and American Heart Association (AHA) published a landmark guideline document describing early appropriate use criteria for coronary interventions [ ]. This document proposed a lesion-specific classification system intended to predict the likelihood of procedural success and risk of acute vessel closure with balloon angioplasty, describing lesions as type A, B, or C in order of escalating complexity and risk. Aside from further subcategorization of type B lesions into B1 and B2 two years later, this classification system has remained unchanged since its inception nearly 40 years ago [ ]. However, the dramatic evolution of interventional cardiology as a field over that same period begs the question of whether this original lesion classification system remains prognostically useful today.