Percutaneous coronary intervention from COURAGE to ISCHEMIA and beyond

Abstract

Multiple randomized clinical trials and observational studies in patients with chronic coronary artery disease have evaluated whether revascularization, in particular PCI, can reduce the incidence of future cardiovascular events and relieve angina. Perhaps the two most widely quoted trials are COURAGE and ISCHEMIA. In both trials revascularization did not reduce the incidence of cardiovascular death or non-fatal events. In both, revascularization did relieve angina, particularly in patients with severe pain. From the time of COURAGE to ISCHEMIA there were also multiple developments. In particular improved stent technology with second and third generation drug eluting stents in ISCHEMIA compared to bare metal stents in COURAGE. There was also the development of new methods to evaluate ischemia, in particular the potential surrogate fractional flow reserve. This period also saw improvement and maturation of coronary computed tomography angiography to assess coronary anatomy non-invasively. There was also greater emphasis on more intensive, guideline directed medical therapy to treat dyslipidemia and hypertension. There has also been greater recognition that not all angina is due to epicardial obstructive disease. Microvascular disease and coronary spasm are responsible for much of the symptom burden of ischemia. These data have led to a paradigm shift toward a more nuanced approach to treating stable ischemic heart disease, with less need for revascularization except in cases of particularly severe anatomic disease or unremitting symptoms while on optimal medial therapy. In recognition of the importance of disparities in cardiovascular health, it is crucial to implement preventive strategies with optimal medical therapy in the community.