The Relationship between Renal Function and Renal Blood Flow in Patients with Coronary Slow Flow

Objective: Coronary slow flow (CSF) is a phenomenon characterized by slowly flowing contrast medium through the epicardial coronary arteries during angiographic examination without detectable stenosis or obstruction. To our knowledge, the relationship between CSF and renal blood flow has not been investigated. Therefore, this study investigated the relationship between CSF and renal blood flow. Material and methods: The study included 25 consecutive patients who were diagnosed with CSF at the Cardiology Outpatient Clinic between August 2012 and June 2013, and 25 consecutive subjects who presented to the Cardiology Outpatient Clinic without CSF. Doppler ultrasound was performed in all subjects. Result: The right and left renal artery flow rates were significantly lower in the CSF group (p=0.011, p=0.006). Serum creatinine was significantly higher in the CSF group compared to the controls (0.71 ± 0.12 vs.0.83 ± 0.11mg/dl, p=0.001), while the glomerular filtration rate (GFR) was significantly lower in the CSF group (116.1 ± 28.6 vs. 98.7±19, p=0.018). There was a significant negative correlation between mean Thrombolysis in Myocardial Infarction frame count and GFR (R2 linear = 0.093, p = 0.035). Conclusion: We found that the renal artery flow rate and GFR are reduced and creatinine levels elevated in CSF patients. Therefore, renal function is impaired in patients with CSF; the underlying cause could be endothelial dysfunction.