This report describes the baseline angiographic findings in the Bypass Angioplasty Revascularization Investigation (BARI) 2 Diabetes (BARI 2D) trial, a randomized study that was initiated after the original BARI trial (BARI 1). Unlike BARI 1, which compared coronary artery bypass graft surgery with coronary angioplasty (percutaneous coronary intervention) in patients with and without diabetes, BARI 2D is investigating early versus deferred revascularization as needed in selected patients with type 2 diabetes mellitus and significant stable coronary artery disease (CAD). This analysis included 1,773 patients without previous procedures. The intended mode of revascularization, percutaneous coronary intervention or coronary artery bypass graft surgery, was specified before randomization. Angiographic findings in those randomized to revascularization versus medical treatment were similar. Overall, the mean number of lesions >or=20% diameter stenosis was 4.6 +/- 2.3, and the myocardial jeopardy index was 46 +/- 24%. Patients selected for the coronary artery bypass graft stratum had a higher mean number of lesions >or=20% diameter stenosis (5.7 vs 4.0, p <0.0001) and a higher myocardial jeopardy index (61% vs 38%, p <0.0001) than those selected for the percutaneous coronary intervention stratum. Female gender, black race, and higher body mass index were associated with less extensive CAD, whereas a history of hypertension, age at entry, low-density lipoprotein cholesterol, and ankle-brachial index <or=0.9 were associated with more extensive CAD. In conclusion, BARI 2D patients, who by design have mild or no symptoms, demonstrate considerable variation in the extent of CAD and amount of jeopardized myocardium. Coronary arteriographic findings are consistent with the intent of the design of BARI 2D. Certain baseline and clinical features were associated with the extent of disease and myocardial jeopardy.