Evolution of Complex Percutaneous Coronary Intervention
A recent publication from the NHLBI-sponsored PTCA and Dynamic registries sheds light on temporal trends in PCI spanning the several decades and multiple technological eras that have passed since the origins of the procedure. Specifically, the report documented the ingress of the field into clinical and procedural scenarios that fall under the rubric of complex PCI.6 Over the 20-year period studied, latter PCI cohorts were characterized by greater proportions of lesions bearing thrombus or calcium and patients with more medical comorbidities compared with the original PTCA cohort. Within the five consecutive Dynamic Registry waves studied (1997–2006), a period notable for the adoption of atherectomy, thrombectomy, cutting/scoring balloon angioplasty, and routine use of bare metal stents (BMS) and, later, drugeluting stents (DES), the proportion of American College of Cardiology/American Heart Association (ACC/AHA) Type C lesions intervened upon grew. Although initial technical success rates were reportedly high, lesions bearing markers of complexity, such as bifurcation disease, ostial location, calcification, and total occlusion, accounted for a significant proportion (9–36 %) of patients requiring repeat PCI within 30 days of their index intervention. Other investigators have independently confirmed in concurrent datasets that complex PCI (lesions evidencing thrombus, calcification, bifurcation or ostial location, chronic occlusion), was also associated with increased in-hospital and 1-year mortality rates compared with PCI of simpler lesions.7 Two large studies have now demonstrated that public reporting of PCI outcomes ostensibly influences the behavior and case selection choices of IC operators, suggesting that operators may be veering away from complex cases they believe will result in poorer outcomes.8,9 These data lend insight into the nuanced and, at times, conflicting considerations that factor into case selection and strategy for complex PCI. Fortunately, however, such considerations have not impeded the advancement of PCI techniques and technologies that have continued to flourish, fueled by scientific innovation and the clinical need for minimally invasive solutions to the growing burden of advanced coronary heart disease. Highlighted below are selected procedural and cost considerations in complex PCI subsets with particular focus on bifurcation disease, representing a commonly encountered, technically challenging, and well-studied complex lesion subset.