Coronary artery disease is a major social problem. However, its epidemiology, pathophysiology, clinical course, diagnostic efficiency and therapeutic potential differ significantly with regard to gender and age. There are few comparative data available on morphological differences and immediate results of direct percutaneous interventions, aorto-coronary bypass grafting, complication rate, risk factors for developing complications after invasive procedures in CAD patients of both sexes and in various age groups. The aim of the study was to identify differences in the location and morphology of coronary plaque and left ventricular function in CAD patients with regard to gender and age. The study included consecutive patients with coronary artery disease diagnosed and treated in the Department of Hemodynamics and Angiocardiography Jagiellonian University Medical College from June 1997 to June 1998. Coronary angiography group, consisting of 1374 patients, 1004 men (73.1%) and 370 women (26.9%), of whom 1146 (83.4%), 890 men (77.7%) and 256 women (22.3%), were included in the final morphological and clinical analysis and in whom coronary angiography confirmed the presence of coronary plaque. The subgroups were further subdivided into two age groups: below and over 50 years of age. Clinical, angiographic and hemodynamic data were analysed retrospectively. Analysis revealed that among patients after invasive diagnosis because of suspected coronary artery disease atherosclerotic lesions in epicardial coronary vessels were significantly more frequently confirmed in men. In patients of both sexes the proportion of patients with angiographically confirmed lesions rises with age. In patients with angiographically documented coronary artery diseases the location and morphology of stenosis in epicardial coronary vessels differs between sexes in the corresponding age groups. Left ventricular function is better preserved in women.