Coronary atherosclerosis: current therapeutic approaches and future trends.
Invasive cardiovascular procedures, such as percutaneous translumenal coronary angioplasty (PTCA) and aorto-coronary bypass surgery (ACBS), that are currently employed in treating the coronary stenosis or occlusion caused by atherosclerosis represent a major therapeutic advance for managing coronary heart disease (CHD). However, the cellular proliferative response and associated intimal hyperplasia that can follow the damage to blood vessels that occurs with these procedures leads to late complications which cannot be effectively controlled by presently available drugs. Hence, a new approach is required for managing these complications, termed "restenosis" (in the case of PTCA) or "stenosis" (in the case of ACBS). Existing drug therapy is reviewed and some new approaches to this problem are provided herein. Further studies of growth factors and other substances that influence the cellular proliferative response that follows injury to the blood vessel wall could lead to the development of effective therapy. Inhibition of intimal hyperplasia and/or acceleration of endothelial cell re-growth provide a basis for such new approaches. Platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF), as well as endothelium-derived relaxing factor(s) (EDRF) and calcitonin gene-related peptide (CGRP) are among the substances discussed. Modification of certain currently available drugs (e.g. Ca(2+)-antagonists) could also be of value in meeting this therapeutic demand.