Objective: Coronary slow flow (CSF) phenomenon is characterized by delayed opacification of coronary vessels in a normal coronary angiogram. Although clinical and pathological features have been previously described, the underlying pathophysiology has not been fully understood yet. Aortic elastic properties have a predictive value in detecting early stages of atherosclerosis. In this study, we aimed to the evaluate the elastic properties of ascending aorta in patients with CSF.
Materials and Methods: This single-center study enrolled 50 angiographically identified patients with CSF (23 female, mean age: 51.6 ± 9.7 years), along with 50 controls (19 female, mean age: 53.5 ± 8.7 years) with normal coronary flow. The quantitative measurement of coronary blood flow was performed using the thrombolysis in myocardial infarction frame count method. Aortic elastic parameters including aortic strain, aortic distensibility, aortic stiffness index and aortic compliance were calculated using M-mode echocardiography derived aortic diameters using accepted formulae.
Results: There was no significant difference in terms of clinical, demographic, echocardiographic and laboratory parameters between the patients with CSF and the controls. The hemodynamic parameters including aortic pulse pressure, aortic mean pressure, aortic fractional pulse pressure and aortic pulsatility index were similar between patients with CSF and controls. Systolic and diastolic aortic diameters and pulsatile aortic diameter change were similar between the groups. There was also no significant difference in terms of aortic strain, aortic distensibility, aortic stiffness index and aortic compliance between the groups.
Conclusion: The results demonstrated that there was no significant difference in terms of hemodynamic parameters and elastic properties of ascending aorta between CSF patients and control group with a similar risk profile and demographic characteristics. Further large scale studies are required to determine the relationship between CSF and elastic properties of aorta.