ABSTRACT
Coronary revascularization procedures by means of percutaneous coronary interventions (PCI) or coronary artery bypass graft surgeries (CABG) are performed daily worldwide for the treatment of patients with myocardial ischemia. Nevertheless, angina remains a signifi cant clinical problem. In fact, large clinical trials consistently report that many chronic angina patients present with persistent symptoms after coronary revascularization (Table 9.1) (Boden et al. 2007). Of those, as many as two thirds might require one or more classical anti-angina agents (Holubkov et al. 2002) and, yet
the results are not optimal. Revascularization procedures (either percutaneous or surgical) are performed with the aim of removing the fl ow limiting stenosis from the epicardial coronary artery. This rationale is in line with the main pathophysiological mechanism underlying angina (epicardial stenosis) and the benefi t obtained in the majority of patients undergoing revascularization is a witness. However, there are three main groups of angina patients to be considered: 1. Those who are deemed to be unsuitable for coronary revascularization because of diffuse coronary artery disease (CAD) (refractory angina). Importantly, this subset represents an increasing population, particularly among diabetic and elderly patients; 2. Those who experience recurrent angina after percutaneous or surgical coronary procedures (recurrent angina) for which, several potential causes, such as bypass graft failure, restenosis, or atherosclerotic disease progression have been identifi ed as the cause of symptom reoccurrence; 3. Those who undergo successful revascularization, in which none of the above mentioned factors can be identifi ed as the cause of symptom reoccurrence (persistent angina). In this latter group, factors other than epicardial stenosis, such as microvascular dysfunction have been suggested as the underlying physiopathological mechanism for persistent symptoms.
