The study examines clinical outcomes in patients who undergo percutaneous coronary revascularization, because a major problem remains the frequent (20 percent-40 percent) occurrence of coronary restenosis and new cardiac events in the six months after the intervention. These adverse outcomes have substantial impact on the costs of medical care and patients' quality of life. Since previous research has not examined the role of behaviorally-induced changes in immune parameters in the prediction of CAD progression, the following immunological measures will be examined: cytokines (IL-1B, IL-4, IL-6, IFNy, TNFa), acute phase proteins (CRP, fibrinogen), lymphocyte counts and differential, adhesion molecules (ICAM-1, LFA, L-selectin), and a composite measure of pathogen burden (CMV, H. pylori, C. pneumoniae). Using a longitudinal design, this project will determine the time course of changes in depression and changes in immune parameters. Moreover, the present study will determine the contribution of behavioral and immunological factors in the clinical progression of coronary disease following coronary angioplasty. These data may therefore improve the identification of patients at risk for recurrent cardiac events and restenosis after coronary angioplasty, and provide further understanding of the pathophysiological mechanisms involved in coronary disease progression.