Transmyocardial and percutaneous myocardial revascularization: current concepts and future directions

Various therapeutic modalities have been developed to limit ischemia in patients with coronary artery disease (CAD). Restoring blood flow to ischemic tissue is the most effective means of limiting ischemia and controlling angina pectoris in these patients. In the majority of patients with CAD, relief of symptoms is achieved with coronary artery bypass graft (CABG) surgery, percutaneous coronary intervention (PCI) or medical treatment. Angioplasty combined with stent placement is currently the most frequently applied non-surgical method of relieving coronary ischemia. However, an increasing number of CAD patients have angina pectoris that is refractory to medical treatment and whose disease is not amenable to conventional revascularization techniques. A large number of these patients have already undergone several revascularization procedures but continue to have notable progression of their disease. The clinical and pathophysiologic spectrum of these patients varies markedly. Most have chronic angina limiting their quality of life. In some patients the pathophysiology is dominated by repetitive stunning or myocardial hibernation, with heart failure as the predominant clinical presentation (ischemic cardiomyopathy). In many of these patients, cardiac transplantation remains the most viable option. In fact, almost half of the cardiac transplantations performed in the USA are in patients with ischemic heart disease associated with left ventricular dysfunction. Despite the major advances in transplant immunology, surgical techniques and survival, the availability of a sufficient number of donors remains a major limiting factor in the widespread use of this treatment modality. As a result, a significant number of patients die each year because of this shortage. A number of novel techniques have been developed in an attempt to reduce ischemia and improve coronary perfusion in patients with predominant ischemia, preserved left ventricular (LV) function and refractory angina who are not amenable to standard revascularization techniques. Therapeutic angiogenesis (as described in Part I of this series) and myocardial laser revascularization techniques are now being investigated extensively for this group of patients. On the other hand, in patients with advanced ischemic cardiomyopathy and predominant heart failure symptoms for whom therapeutic angiogenesis and laser revascularization techniques have not yet been applied; drug therapy, mechanical support devices and cardiac and myocyte transplantation may be implemented. The focus of this review is to report advances in laser myocardial revascularization techniques and determine whether these techniques are applicable to patients with ischemic heart disease (ISHD) and LV dysfunction. From the Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama. Submitted March 6, 2002; revised June 25, 2002; accepted October 8, 2002. Reprint requests: Raymond L. Benza, MD, Division of Cardiovascular Disease,Department of Medicine, University of Alabama at Birmingham, 328A THT, 1900 University Boulevard, Birmingham, Alabama 35294-0006. Telephone: 205-934-3438. Fax: 205-975-9320. E-mail: rbenza@cardio.dom.uab.edu J Heart Lung Transplant 2003;22:837–842 Copyright © 2003 by the International Society for Heart and Lung Transplantation. 1053-2498/03/$–see front matter doi:10.1016/S1053-2498(02)00814-8