Abstract
Refractory angina is a major clinical challenge in contemporary cardiovascular medicine. As therapeutic strategies evolve, there is increased life expectancy for ischemic heart disease with more patients reaching advanced stages. Due to a better understanding of the disease process and technological advances, coronary revascularization, by means of coronary by-pass grafting (CABG) and percutaneous coronary interventions (PCI), is now offered to a wide spectrum of high-risk patients. The inception of drug eluting stents in routine clinical practice has reduced the restenosis rates to single digits [1, 2], extending the indications of PCI to poor operative candidates with unprotected left main stenosis or diabetics with diffuse small vessel disease. In a similar fashion, more generalized use of major surgical revascularization breakthroughs, such as off-pump CABG and arterial grafts, have resulted in significant improvements in surgical outcomes [3]. Despite these advances, a significant proportion of patients with preserved left ventricular fraction and no life-threatening arrhythmias remain symptomatic with severe debilitating angina due to progression of native atherosclerotic disease associated with failure or unfeasibility of revascularization. In a prospective observational study, Hemingway et al. showed that at 1-year follow-up angina persists in 52% of patients treated with PCI and 40% of those treated with CABG [4]. Similar findings were observed in the multicenter international ARTS randomized trial, in which only 19% of PCI patients and 38% of CABG patients were free of angina and antianginal therapy at 1-year follow-up [5]. Moreover, in a meta-analysis of 11 randomized trials comparing PCI with medical therapy in stable patients with chronic coronary artery disease, PCI offered no survival benefit [6].