Goal: To indicate the influence of risk factors for the development of coronary artery disease (CAD) on coronary flow reserve (CFR) values assessed by transthoracic echocardiography (TTE) in patients without verified CAD.
Methods: The paper presents an analysis of the available literature from reference databases covering the mentioned topic.
Results: TTE-CFR presents a ratio of hyperaemic coronary blood flow during maximum vasodilation in relation to resting coronary blood flow. The most commonly used vasodilators are dipyridamole and adenosine (adenosine 140 mcg⁄kg⁄min (1-2 min), dipyridamole 0.84 mg⁄kg⁄6 min). Age and female gender have a lesser effect on the values of hyperemic CFR. Ethnic differences (vascularization, left ventricle structure) can influence the CFR values. Also, obesity, smoking, hyperlipidemia, elevated values of low-density lipoproteins (LDL), arterial hypertension, diabetes mellitus, and obstructive sleep apnea in a healthy population can have a negative effect on CFR values.
Conclusion: There is evidence of the effect of risk factors for CAD on CFR values in a population without established pathology. (1-3) It is a marker of the early stages of coronary atherosclerosis (a tool in the stratification of patients regarding cardiovascular risk, and it could be a guide in the primary prevention of cardiovascular disease). Also, TTE-CFR<2 has good sensitivity and specificity to predict the significance of stenosis. Clinical presentation of the patient should be a part of the mosaic of interpretation of test results. CFR is an additional test, and stress echocardiography presents the first choice in the evaluation of ischemic heart disease.