purpose: The purpose of this study was to examine the relationship between psychiatric depression and ventricular arrhythmias in patients with coronary artery disease (CAD). The hypothesis was that depressed patients with CAD would have a higher prevalence of ventricular tachycardia (VT) than nondepressed patients with CAD. patients and methods: One hundred three patients who were found to have significant CAD by elective diagnostic cardiac catheterization were administered a standardized psychiatric interview and underwent 24-hour Holter monitoring. results: Twenty-one patients (20%) met the criteria for either major or minor depression. There were no significant differences between depressed and nondepressed patients with CAD in severity of CAD or in ventricular function. Five (23.8%) of the depressed patients and three (3.7%) of the nondepressed patients exhibited episodes of VT during 24 hours of Holter monitoring (p <0.008). This difference remained significant even after controlling for relevant covariates. conclusions: We conclude that there is a higher prevalence of VT among patients with CAD and depression than among those CAD patients without depression. This may help to explain the increased risk for cardiac mortality in depressed patients with CAD.