Impact of Cell Therapy on Myocardial Perfusion and Cardiovascular Outcomes in Patients With Angina Refractory to Medical Therapy

The prevalence of refractory angina (RFA) in the United States is estimated between 600 000 and 1.8 million. With the advances made in the management of coronary artery disease, prolonged survival, and an aging population, the incidence of debilitating angina refractory to medical therapy (also referred to as no-option angina) is increasing. These patients present a major clinical problem because they either are ineligible for revascularization or do not adequately benefit from it because of the presence of microvascular disease; no other effective treatment is available. RFA places a great burden on society because of not only recurrent hospitalization and resource use but also disability and lost productivity. Therefore, many novel therapeutic options have been explored in this patient population, including enhanced external counterpulsation, transcutaneous electric nerve stimulation, and transmyocardial laser revascularization; however, the response to these approaches has been disappointing. Moreover, the majority of studies of novel therapeutic modalities for ischemic artery disease have been conducted in stable patients rather than in those refractory to medical therapy.