Objectives: Non-obstructive coronary disease has been recognized for several years as an important cause of myocardial ischemia and major cardiovascular events, especially in the female population, but the pathophysiological mechanisms and risk factors for this disease are still insufficiently investigated. The aim of this research is to examine the incidence of nonobstructive coronary disease in patients who underwent coronary angiography due to suspected coronary disease, to determine the influence of traditional risk factors and psychological burdens in this disease in relation to obstructive coronary disease, and to examine the influence of tortuosity of the coronary arteries and a certain type of coronary supply in non-obstructive coronary artery disease. Study design: The study is designed as a cross-sectional study which examined the presence of risk factors and analyzed the coronary anatomy in subjects with non-obstructive coronary disease compared to subjects with obstructive coronary disease. Participants and methods: The study included 160 subjects over the age of 18 with diagnosed obstructive or non-obstructive coronary disease, a total of 89 men and 71 women, who presented as ACS or CCS. All subjects underwent anamnesis, physical examination, analysis of laboratory findings (cholesterol, triglycerides, HDL, LDL, homocysteine), echocardiographic examination and psychological questionnaire testing. Each subject coronary angiogram was analyzed, with assessment of the type of coronary artery supply and the presence of coronary artery tortuosity. Two methods were used to measure the tortuosity of the coronary arteries on the coronary angiogram - the method of calculating the tortuosity index and the method of angle measurement. In the group of patients with CCS we analyzed the findings of exercise testing or myocardial perfusion scintigraphy, which were performed prior to recruitment to the study. Results: Mean age of the subjects was 61.6 (SD, 10.2), of which 56.9 % were diagnosed with ACS, and 43.1 % with CCS. According to the findings of coronary angiography, the subjects were divided into a group with non-obstructive coronary disease and a group with obstructive coronary disease. Tortuosity of coronary arteries measured by the method of angle measurement as well as the method of calculating the tortuosity index showed significantly more tortuosity of coronary arteries in the subgroup with non-obstructive coronary disease compared to the control group for all three coronary arteries – LCX, LAD and RCA. The results showed a significant correlation between LCX and LAD tortuosity and signs of ischemia in specific regions of the myocardium that are irrigated by these vessels. The level of stress was significantly higher in the subgroup with non-obstructive coronary disease, where 18.8 % of patients with non-obstructive coronary disease had the highest level of stress. Conclusion: Female sex, tortuosity of coronary arteries, left coronary dominance, extremely high stress level and elevated cholesterol are independent predictors of non-obstructive coronary disease.