Coronary slow flow: Benign or ominous?

Comparison of the effect of uric acid/albumin ratio on coronary slow flow with other inflammation-based markers

Background: Many inflammation-based markers (IBMs) have been shown to be closely related to coronary slow flow (CSF), but the effect of the uric acid/albumin ratio (UAR) on CSF and its relationship with other IBMs are not clearly known. In this study, we aimed to compare the effects of UAR and other IBMs on CSF. Methods: After the exclusion criteria, 126 patients with CSF detected on coronary angiography and 126 subjects with normal coronary flow as the control group were included in the study. Results: UAR was determined as an independent predictor for CSF. In addition, the UAR was superior to other IBMs in detecting CSF (p < 0.05 for all). Conclusion: This study is the first to investigate the effect of UAR on CSF in comparison with other IBMs.

Relationship between quantitative epicardial adipose tissue based on coronary computed tomography angiography and coronary slow flow

BACKGROUND

The purpose of this study was to explore the relationship between quantitative epicardial adipose tissue (EAT) based on coronary computed tomography angiography (CCTA) and coronary slow flow (CSF).

METHODS

A total of 85 patients with < 40% coronary stenosis on diagnostic coronary angiography were included in this retrospective study between January 2020 and December 2021. A semi-automatic method was developed for EAT quantification on CCTA images. According to the thrombolysis in myocardial infarction flow grade, the patients were divided into CSF group (n = 39) and normal coronary flow group (n = 46). Multivariate logistic regression was used to explore the relationship between EAT and CSF. Receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic value of EAT in CSF.

RESULTS

EAT volume in the CSF group was significantly higher than that of the normal coronary flow group (128.83± 21.59 mL vs. 101.87± 18.56 mL, P < 0.001). There was no significant difference in epicardial fat attenuation index between the two groups (P > 0.05). Multivariate logistic regression analysis showed that EAT volume was independently related to CSF [odds ratio (OR) = 4.82, 95% confidence interval (CI): 3.06-7.27, P < 0.001]. The area under ROC curve for EAT volume in identifying CSF was 0.86 (95% CI: 0.77-0.95). The optimal cutoff value of 118.46 mL yielded a sensitivity of 0.80 and a specificity of 0.94.

CONCLUSIONS

Increased EAT volume based on CCTA is strongly associated with CSF. This preliminary finding paves the way for future and larger studies aimed to definitively recognize the diagnostic value of EAT in CSF.

Evaluation of the relationship between clinical and laboratory risk factors in atherosclerosis patients with coronary slow flow: a case-control analysis

BACKGROUND

Coronary slow flow (CSF) is an angiographic entity distinguished by the delayed filling of the epicardial coronary arteries in the lack of significant obstructive artery disease. The pathological causes are still unknown. This study aimed to elucidate the relationship between clinical and laboratory-related risk factors in atherosclerosis patients diagnosed with CSF.

RESULTS

The research encompassed a study group of 142 individuals, with a mean age of 52.47 ± 10.62, and a male representation of 47.7%. A thorough statistical analysis was conducted, indicating that there were no noteworthy variations in age, gender, smoking history, hematocrit, blood sugar, and HDL levels between the groups of cases and controls (P > 0.05). Subsequent analysis of the data indicated that there were significant differences in history of hypertension, LDL, and BMI measurements between the groups of subjects who were designated as cases and those who were designated as controls. Our study revealed that male gender, a history of hypertension, and BMI were identified as independent predictors of CSF (P < 0.05).

CONCLUSIONS

After modeling regression, we were able to conclude that male gender, BMI, and history of hypertension are reliable predictors of slow coronary flow. These findings add to our growing understanding of the complex interplay between clinical and laboratory risk factors in the development and progression of CSF.

Assessment of indices of conjunctival microvascular function in patients with and without obstructive coronary artery disease

BACKGROUND

Atherosclerotic heart disease often remains asymptomatic until presentation with a major adverse cardiovascular event. Primary preventive therapies improve outcomes, but conventional screening often misattributes risk. Vascular imaging can be utilised to detect atherosclerosis, but often involves ionising radiation. The conjunctiva is a readily accessible vascular network allowing non-invasive hemodynamic evaluation.

AIM

To compare conjunctival microcirculatory function in patients with and without obstructive coronary artery disease.

METHODS

We compared the conjunctival microcirculation of myocardial infarction patients (MI-cohort) to controls with no obstructive coronary artery disease (NO-CAD cohort). Conjunctival imaging was performed using a smartphone and slit-lamp biomicroscope combination. Microvascular indices of axial (V_a) and cross-sectional (V_cs) velocity; blood flow rate (Q); and wall shear rate (WSR) were compared in all conjunctival vessels between 5 and 45 μm in diameter.

RESULTS

A total of 127 patients were recruited (66 MI vs 61 NO-CAD) and 3602 conjunctival vessels analysed (2414 MI vs 1188 NO-CAD). Mean V_a, V_cs and Q were significantly lower in the MI vs NO-CAD cohort (V_a 0.50 ± 0.17 mm/s vs 0.55 ± 0.15 mm/s, p < 0.001; V_cs 0.35 ± 0.12 mm/s vs 0.38 ± 0.10 mm/s, p < 0.001; Q 154 ± 116 pl/s vs 198 ± 130 pl/s, p < 0.001). To correct for differences in mean vessel diameter, WSR was compared in 10-36 μm vessels (3268/3602 vessels) and was lower in the MI-cohort (134 ± 64 s^-1 vs 140 ± 63 s^-1, p = 0.002).

CONCLUSIONS

Conjunctival microcirculatory alterations can be observed in patients with obstructive coronary artery disease. The conjunctival microvasculature merits further evaluation in cardiovascular risk screening.

The Systemic Immune-Inflammation Index May Predict the Coronary Slow Flow Better Than High-Sensitivity C-Reactive Protein in Patients Undergoing Elective Coronary Angiography

Methods

A total of 197 patients (102 patients with CSF; 95 patients with normal coronary flow) were included in this retrospective study. Clinical and angiographic characteristics of patients were obtained from hospital records.

Results

Patients with CSF had higher SII, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte (PLR), and high-sensitivity C-reactive protein (hsCRP) levels compared with the control group. Body mass index (p=0.022, OR 1.151, 95% CI 1.121–1.299), low-density lipoprotein (p=0.018, OR 1.028, 95% CI 1.005–1.052), hsCRP (p=0.044, OR 1.161, 95% CI 1.004–1.343), and SII (p < 0.001, OR 1.015, 95% CI 1.003–1.026) were independent predictors of CSF in the multivariable analysis. The optimal cutoff value of SII in predicting CSF was >877 in ROC curve analysis (p < 0.001, AUC = 0.892, 95% CI 0.848–0.936). This cutoff value of SII predicted the CSF with a sensitivity of 71.5% and specificity of 92.4%. Spearman correlation analysis showed a positive correlation between the mean TFC value and PLR, NLR, hsCRP, and SII.

Conclusions

SII may be used as a better indicator for the prediction of CSF than hsCRP.

Assessment of the conjunctival microcirculation for patients presenting with acute myocardial infarction compared to healthy controls

Microcirculatory dysfunction occurs early in cardiovascular disease (CVD) development. Acute myocardial infarction (MI) is a late consequence of CVD. The conjunctival microcirculation is readily-accessible for quantitative assessment and has not previously been studied in MI patients. We compared the conjunctival microcirculation of acute MI patients and age/sex-matched healthy controls to determine if there were differences in microcirculatory parameters. We acquired images using an iPhone 6s and slit-lamp biomicroscope. Parameters measured included diameter, axial velocity, wall shear rate and blood volume flow. Results are for all vessels as they were not sub-classified into arterioles or venules. The conjunctival microcirculation was assessed in 56 controls and 59 inpatients with a presenting diagnosis of MI. Mean vessel diameter for the controls was 21.41 ± 7.57 μm compared to 22.32 ± 7.66 μm for the MI patients (p < 0.001). Axial velocity for the controls was 0.53 ± 0.15 mm/s compared to 0.49 ± 0.17 mm/s for the MI patients (p < 0.001). Wall shear rate was higher for controls than MI patients (162 ± 93 s-1 vs 145 ± 88 s-1, p < 0.001). Blood volume flow did not differ significantly for the controls and MI patients (153 ± 124 pl/s vs 154 ± 125 pl/s, p = 0.84). This pilot iPhone and slit-lamp assessment of the conjunctival microcirculation found lower axial velocity and wall shear rate in patients with acute MI. Further study is required to correlate these findings further and assess long-term outcomes in this patient group with a severe CVD phenotype.

Determination of Myocardial Scar Tissue in Coronary Slow Flow Phenomenon and The Relationship Between Amount of Scar Tissue and Nt-ProBNP

Fundamento

A fisiopatologia e o prognóstico não estão claramente determinados nos pacientes com fenômeno do fluxo coronário lento (FCL). Esses pacientes apresentam várias condições clínicas, que variam desde quadro assintomático até internação hospitalar com morte cardíaca súbita.

Objetivos

Nosso objetivo foi avaliar os achados da ressonância magnética cardíaca (RMC) com o realce tardio pelo gadolínio (RTG), como um indicador de fibrose miocárdica. Também buscamos determinar a relação entre a presença de fibrose miocárdica e os níveis de NT-proBNP em pacientes com FCL na artéria coronária descendente anterior esquerda (DAE).

Métodos

Ao todo, 35 pacientes, entre 31 e 75 anos de idade, foram incluídos. Os pacientes estudados (n=19) apresentaram artérias coronárias epicárdicas normais na angiografia, mas tinham FCL na DAE. O grupo controle de pacientes (n=16) apresentou artérias coronárias epicárdicas normais e níveis de escore TIMI normais na angiografia. Em ambos os grupos, os pacientes foram examinados com RMC para a detecção de presença de fibrose miocárdica. Além disso, níveis plasmáticos de NT-proBNP foram medidos. Valores de p < 0,05 foram considerados significativos.

Resultados

A taxa de fibrose miocárdica foi significativamente maior na RMC para os pacientes com FCL (p=0.018). Uma quantidade variável de tecido cicatricial foi detectada no ápice ventricular esquerdo em 7 pacientes e nas regiões inferior e inferolateral em 3 pacientes. Não foram observadas diferenças nos níveis de NT-proBNP nos pacientes com FCL. Entretanto, os níveis de NT-proBNP foram maiores nos pacientes com FCL, que apresentaram fibrose miocárdica na RMC (p=0.022).

Conclusões

Em suma, o RTG na RMC mostrou que a cicatriz miocárdica isquêmica pode estar presente nos pacientes com FCL. Esses resultados indicam que o FCL pode nem sempre ser inofensivo. (Arq Bras Cardiol. 2020; 114(3):540-551)

Anxiety and depression relationship with coronary slow flow

Background

Psychiatric disorders (depression / anxiety) are linked to coronary artery disease (CAD). Coronary slow flow (CSF) is a relatively common form of CAD with the same underlying mechanisms that are attributed to many anatomic and pathophysiologic factors. However, the relationship between psychiatric disorders and CSF is less well-established; and this is the aim of this study.

Methods

This cross-sectional observational study was conducted on the first 50 consecutive patients diagnosed with CSF by elective coronary angiography (CAG). They were compared with another 50 consecutive patients showing normal coronaries by CAG. Beck Anxiety Inventory and Beck Depression Inventory were used for assessment. CSF was diagnosed by coronary angiography “Thrombolysis In Myocardial Infarction” frame count. Lipid profile was obtained for all patients.

Results

Traditional risk factors (male gender, smoking, total cholesterol, low-density lipoproteins and triglycerides) were higher in the CSF group. Depression and anxiety scores were also higher in the CSF group. On multivariate analysis, male gender, depression and high triglycerides were the only significant independent predictors of CSF. A significant correlation existed between CSF and both anxiety and depression scores. Both scores were also significantly higher in multivessel vs single vessel affection.

Conclusion

Psychiatric depression, male gender and high triglycerides are highly associated with CSF in patients undergoing elective CAG. There is a significant correlation between CSF severity and the severity of both anxiety and depression. Further studies are warranted to explore the impact of psychological intervention on CSF and its long-term outcome.

Clinical Profile and Outcome in Patients with Coronary Slow Flow Phenomenon

The coronary slow flow phenomenon (CSFP) is a poorly recognized clinical entity characterized by delayed distal vessel opacification in the absence of epicardial coronary stenosis and presently lack of specific data on the clinical profile and outcome. We investigated a cohort of 429 patients who fulfilled the criteria for CSFP to explore the clinical feature, outcome, and risk factor of prognosis. Two teams (clinical center and core lab) were blind to patient data for the assessment of coronary angiograph using corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC). The study cohort consisted of 429 patients (294 men, 68.5%), aged from 30 to 78 years (mean, 54 years). Two hundred patients (46.6%) out of 429 patients had a history of hypertension, 72 (16.8%) had diabetes mellitus, and 222 (51.7%) had dyslipidemia. All the rates of agreement between two teams in evaluating whether normal flow (CTFC ≤ 27 frames) or slow flow (CTFC > 27 frames) were moderate (0.40 < κ < 0.75) for the three arteries. Follow-up (mean, 3.8 years) was done for 421 patients (98.1%). The major adverse cardiovascular events (MACE) occurred in 39 patients (9.3%) out of 421 patients. Multivariate analysis showed that the risk of MACE approximately doubles with age >50 years (hazard ratio (HR) = 2.2, 95% CI: 1.0 to 4.9, and P=0.042), hypertension (HR = 2.1, 95% CI: 1.1 to 4.2, and P=0.021), and dyslipidemia (HR = 2.0, 95% CI: 1.0 to 3.9, and P=0.042). CSFP affects predominantly patients at middle age and above but can occur in any age group; CSFP should be more concerned, particularly in patients >50 years old with hypertension and dyslipidemia.