Background: In some patients with chest pain, selective coronary angiography reveals Slow contrast agent passage through the epicardial coronary arteries in the absence of stenosis. This phenomenon has been designated the Slow coronary flow (SCF) phenomenon.Objectives: In this study, we aimed to describe the demographic and clinical findings and presence of common atherosclerosis risk factors in patients with the SCF phenomenon.Patients and Methods: Between October 2014 and March 2015, demographic data, clinical histories, atherosclerosis risk factors, and laboratory and angiographic findings were recorded for all consecutive patients scheduled for coronary angiography and diagnosed with the SCF phenomenon, as well as a control group (patients with normal epicardial coronary arteries; NECA). SCF was diagnosed based on the thrombolysis in myocardial infarction frame count (TFC). A TFC>27 indicated a diagnosis of SCF phenomenon.Results: Among the 3600 patients scheduled for selective coronary angiography, 75 (2%) met the SCF criteria. SCF and NECA patients did not exhibit statistically significant differences in traditional risk factors except for hypertension, which was more prevalent in SCF than NECA patients (52% versus 31%, P=0.008). A multivariable analysis indicated a low body mass index, presence of hypertension, low high-density lipoprotein cholesterol (HDL-c) level, and high hemoglobin level as independent predictors of the SCF phenomenon; of these, hypertension was the strongest predictor (odds ratio=6.3, 95% confidence interval: 2.2-17.9, P=0.001).Conclusions: The SCF phenomenon is relatively frequent, particularly among patients with acute coronary syndrome who are scheduled for coronary angiography. Hypertension, a low HDL-c level, and high hemoglobin level can be considered independent predictors of this phenomenon.

Background: Several studies have demonstrated an association between vitamin D deficiency and cardiovascular diseases. Slow coronary flow (SCF) is a phenomenon in coronary angiography defined as the Slow (delayed) opacification of the epicardial coronary arteries with contrast agents in the absence of coronary obstruction. We sought to evaluate the level of vitamin D in SCF patients against normal coronary conditions. Methods: This cross-sectional study was carried out on 164 patients admitted for elective coronary angiography. For 15 months, from among these patients, 82 patients with SCF and 82 patients with normal coronary arteries or mild coronary artery disease (CAD) who were matched for age and gender were selected and vitamin D levels were measured accordingly. Results: The mean age of the patients was 56 years in the normal coronary group and 54 years in the SCF group. The mean level of vitamin D was 23. 84 ng/mL in the normal coronary group and 24. 29 ng/mL in the SCF group. Vitamin D deficiency was observed in 44. 4% of the patients in the normal coronary group and 41. 2% of the patients in the SCF group. The Mann– Whitney U test showed no significant difference between the 2 groups in terms of vitamin D levels (P = 0. 96). Conclusions: The level of vitamin D was not significantly different between our 2 groups of patients with SCF and with normal coronary arteries (or mild CAD).

Background: Coronary Slow flow (CSF) is defined as decreased coronary blood circulation velocity and delayed opacification of contrast media during angiography. Evidence is insufficient regarding the course and prognosis of CSF patients. Long-term follow-up can help better understand the physiopathology and outcome of CSF. Accordingly, we assessed the long-term outcomes of CSF patients in this study. Methods: This retrospective cohort study was carried out on 213 CSF patients consecutively admitted to a tertiary health care center from April 2012 through March 2021. After data collection from the patients’,files, follow-up was done via telephone call invitations and assessments of existing data in the outpatient cardiology clinic. The comparative analysis was conducted using a logistic regression test. Results: The mean follow-up length was 66. 26±, 15. 32 months, 105 patients (52. 2%) were male, and the mean age of the patients was 53. 81±, 11. 91 years. The left anterior descending was the main affected artery (42. 8%). At long-term follow-up, 19 patients (9. 5%) required repeated angiography. Three patients (1. 5%) had a myocardial infarction and 5 (2. 5%) died from cardiovascular etiologies. Three patients (1. 5%) underwent percutaneous coronary intervention. No patient required coronary artery bypass grafting. The need for a second angiography had no association with sex, symptoms, and echocardiographic findings. Conclusion: The long-term outcome of CSF patients is good, but their follow-up is necessary for the early diagnosis of cardiovascular-related adverse events.

Background: Noninvasive assessment of arterial stiffness in patients with Coronary Slow flow Phenomenon (CSFP) could be valuable for evaluating cardiovascular risk. Presystolic Wave (PSW) velocity is considered a predictor of cardiovascular disease and a marker of arterial stiffness. This study aimed to evaluate PSW velocity in patients with CSFPMethods: This cross-sectional study investigated patients with acute coronary syndrome, dividing them into two groups: Cerebrospinal Fluid (CSF) and Coronary Normal flow (CNF), with 30 patients in each group. Both groups underwent echocardiography, and PSW velocity was compared between them. Data analysis was performed using SPSS version 24 software.Results: A total of 60 patients were included in the study. The mean ages in the CSF and CNF groups were 49.8±9.6 and 49.6±10.7 yrs, respectively. In the CSF group, 63.33% were female, compared to 43.33% in the CNF group. There were statistically significant differences in Em and aortic aortic Velocity Time Integral (VTI) among echocardiographic variables (p<0.05). However, PSW velocity did not significantly differ between the CNF and CSF groups (33.6±17.4 vs. 37.8±10.4, p=0.26), though it was slightly higher in Slow flow patients.Conclusion: In this study, no significant difference was found in PSW velocity between patients with Slow coronary flow and those with normal coronary flow, and it is not associated with arterial stiffness. Therefore, PSW velocity cannot be used as a predictor of arterial stiffness in CSF patients. Further research is recommended to validate or refute these findings.

Background and Objectives: Coronary Slow flow (CSF) is a phenomenon whose pathophysiology is unclear and is associated with increased cardiac mortality. According to recent studies, serum apelin levels are associated with oxidative stress and inflammation, which may contribute to CSF pathophysiology. We aimed to investigate the possible correlation of serum apelin levels with CSF. Methods: The study included 50 consecutive CSF patients and 50 consecutive patients with normal coronary flow (NCF). We compared serum apelin-13 and other clinical parameters between the groups. Results: CSF group had significantly lower serum apelin levels than the NCF group (P<0. 001). The multiple regression analysis suggested low apelin levels as an independent risk factor for CSF (P<0. 001). We found that the number of TIMI frames was positively correlated with apelin levels (P<0. 001, r=0. 843). According to the receiver operating characteristic curve analysis, serum apelin levels were significant predictors of CSF treatment (P<0. 001). We calculated a cut-off value of 2. 7 ng/ml for serum apelin levels to predict CSF with 84% sensitivity and 64% specificity. Conclusion: This study concluded that the CSF group had lower serum apelin levels than the NCF group. Apelin may have a role in CSF pathogenesis.

Background & Aims: Coronary Slow flow phenomenon (SCF) is normal or near-normal angiographically that is known with delayed passage of contrast in coronary arteries. Etiology of SCF is unknown. Endothelial dysfunction is one of the main factors in the etiology of SCF and vascular endothelium-derived nitric oxide is one of the main biochemical factors in the regulation of vascular tonisity. The aim of this study was to evaluate serum levels of nitric oxide metabolites in SCF patients.Materials and Methods: Thirty patients with SCF (53±11.83 years) and 30 healthy controls (51.37±11.89 years) were entered in the case-control investigation. Cases and controls were matched for age, gender, and body mass index. Three ml of blood samples were collected in tubes. Serum concentrations of NO metabolites were measured by ELISA method (Ltd. Co, China).Results: The mean values of nitric oxide metabolites in controls and patients with SCF was 18.04 ±7.99 and 17.93±4.31mmol/L, respectively; P=0.129.Conclusion: Endothelial dysfunction is the main factor in the pathogenesis of SCF. But in this study, serum levels of nitric oxide metabolites were not statistically significant in patients with SCF patients versus controls. So it was recommended to further investigate with more subjects.

Introduction: This study was conducted to investigate prevalence and predictors of Slow coronary flow phenomenon (SCF) phenomenon. Methods: This cross-sectional study was performed at Imam Ali Cardiovascular Hospital affiliated with the Kermanshah University of Medical Sciences (KUMS), Kermanshah province, Iran. From March 2017 to March 2019, all the patients who underwent coronary angiography were enrolled in this study. Data were obtained using a checklist developed based on the study’ s aims. Independent samples t tests and chi-square test (or Fisher exact test) were used to assess the differences between subgroups. Multiple logistic regression model was applied to evaluate independent predictors of SCF phenomenon. Results: In this study, 172 (1. 43%) patients with SCF phenomenon were identified. Patients with SCF were more likely to be obese (27. 58 ± 3. 28 vs. 24. 12 ± 3. 26, P < 0. 001), hyperlipidemic (44. 2 vs. 31. 7, P < 0. 001), hypertensive (53. 5 vs. 39. 1, P < 0. 001), and smoker (37. 2 vs. 27. 2, P = 0. 006). Mean ejection fraction (EF) (51. 91 ± 6. 33 vs. 55. 15 ± 9. 64, P < 0. 001) was significantly lower in the patients with SCF compared to the healthy controls with normal epicardial coronary arteries. Mean level of serum triglycerides (162. 26 ± 45. 94 vs. 145. 29 ± 35. 62, P < 0. 001) was significantly higher in the patients with SCF. Left anterior descending artery was the most common involved coronary artery (n = 159, 92. 4%), followed by left circumflex artery (n = 50, 29. 1%) and right coronary artery (n = 47, 27. 4%). Body mass index (BMI) (OR 1. 78, 95% CI 1. 04-2. 15, P < 0. 001) and hypertension (OR 1. 59, CI 1. 30-5. 67, P = 0. 003) were independent predictors of SCF phenomenon. Conclusion: The prevalence of SCF in our study was not different from the most other previous reports. BMI and hypertension independently predicted the presence of SCF phenomenon.

BACKGROUND: Slow coronary flow (SCF) phenomenon is an angiographic finding which is defined as Slow contrast passage through coronary arteries which may predispose patients to serious cardiac complications such as fatal arrhythmias. P-wave and QT-interval dispersion are electrocardiographic findings which are related to atrial fibrillation and ventricular tachyarrhythmias. In the present study, the relation between SCF and presence of P-wave and QT-interval dispersion in electrocardiography has been evaluated. METHODS: 47 patients with normal coronary arteries and SCF and 40 patients with normal coronary artery flow without SCF were enrolled in this case control study. Standard electrocardiogram (ECG) was analyzed for P-wave and QT-interval dispersion. SCF was identified in normal coronary vessels by use of Thrombolysis in Myocardial Infarction (TIMI) frame count (TFC) method (TFC ˃ 27). Corrected TIMI frame count (CTFC) of coronary vessels as well as mean CTFC along with QT-interval and P-wave dispersion were compared between 2 groups. The study data were analyzed by SPSS software and P value less than 0. 050 was considered to be significant. RESULTS: QT-interval [76. 17 (35. 23) ms versus 39. 25 (19. 26) ms] and P-wave [39. 74 (17. 48) ms versus 19. 50 (8. 54) ms] dispersion were significantly higher among patients with SCF phenomenon (P ˂ 0. 050). In addition, there was a positive significant linear correlation between TFC and P-wave and QT-dispersion (r = 0. 857, r = 0. 861, respectively, P ˂ 0. 050). CONCLUSION: According to the results, increasing TFC among patients with SCF will result in P wave and QT interval dispersion and therefore this finding can be considered as an indicative marker for cardiac events.