OBJECTIVES: Little is known about treatment of depression in coronary artery disease (CAD) at ambulatory visits in United States. METHODS: Retrospective analyses were conducted of the combined 5-year data (2000-2004) of physician office-based National Ambulatory Medical Care Survey (NAMCS) and outpatient and emergency department based National Hospital Ambulatory Medical Care Survey (NHAMCS). Visits with coronary artery disease (ICD-9-CM 410-414) and depression disorder (296, 311) were identified. The visits combined across the three settings were classified into CAD visits with and without depression. Sample estimates were weighted and projected to the population with 95% confidence intervals. Multivariate logistic regression was used to determine significant characteristics of antidepressant treatment mention at visits. RESULTS: About 1.23 million ambulatory visits or 0.79% (95%CI: 0.51-1.21) of all adult CAD associated visits also had a diagnosis of depression. Antidepressant medication (TCA, MAOI, SSRI, or buproprion) was associated with 7.75% (95%CI: 6.49-9.24) of all CAD associated visits with SSRI being associated with about 5.46% of visits. In multivariate logistic-regression analysis, male gender (adjusted odds-ratio,OR,0.47, 95%CI:0.33-0.68), race other than Caucasian (OR,0.38, 95%CI:0.21-0.69), emergency department (ED) setting (OR,0.32, 95%CI:0.21-0.50), decreased the likelihood while recent years (2002-04) (OR,1.42, 95%CI:1.03-1.96), depression (OR,7.92, 95%CI:1.56-40.42), and any mental health disorder (OR,4.60, 95%CI:1.74-12.14), and number of medications (OR,6.27, 95%CI:3.93-9.99) significantly increased the likelihood of an antidepressant medication at CAD associated visits. CONCLUSION: About 1% and 7.75% of CAD visits were associated with depression, and included antidepressants, respectively. Further research is needed on the less likelihood of antidepressant treatment at visits by male and other ethnic minority patients, and in the ED setting with a diagnosis of CAD.