While the breadth of procedural offerings in interventional cardiology (IC) has exponentially expanded over the past four decades to include cardiac structural, peripheral arterial, and venous interventions, percutaneous coronary intervention (PCI) remains at the core of the field, accounting for the greatest percentage of therapeutic catheter-based procedures performed by IC practitioners in the US. Beginning with the historic series of coronary angioplasties performed by Dr Andreas Grüentzig in 1977, PCI has steadily advanced in its range of application and technical sophistication.1,2 Shortly after the landmark procedures were performed and reported at the Annual Scientific Sessions of the American Heart Association in 1977, a percutaneous transluminal coronary angioplasty (PTCA) registry was established at the National Heart, Lung and Blood Institute (NHLBI) in order to track the expansion, progress, and outcomes of this thenfledgling procedure.3,4 Dorros and colleagues reported on clinical outcomes and complications in the first 1,500 patients undergoing PTCA in the US (September 1977 to April 1981).5 The rate of PTCA success was 63 % at that time and the rate of major peri-procedural complications (myocardial infarction, emergency surgery, or in-hospital death) was 9.2 % with standalone mortality of 1.1 % (0.85 % in patients with single vessel disease; 1.9 % in those with multivessel disease).5 Even in the very earliest PTCA experience, lesion complexity and presenting acuity predictably affected clinical outcomes, a theme that has carried through to contemporary PCI.