Serum uric acid and slow coronary flow in cardiac syndrome X

Development and validation of a nomogram diagnostic model for coronary slow flow patients: A cross-sectional study

In this study, risk factors for coronary slow flow (CSF) patients were examined, and a clinical prediction model was created. This study involved 573 patients who underwent coronary angiography at our hospital because of chest pain from January 2020 to April 2022. They were divided into CSF group (249 cases) and noncoronary slow flow (NCF) group (324 cases) according to the coronary blood flow results. According to a 7:3 ratio, the patients were categorized into a training group consisting of 402 cases and a validation group consisting of 171 cases. The outcome was assessed by employing multiple logistic regression analysis to examine the factors that influenced it. The model's recognizability was assessed by calculating the consistency index and plotting the receiver operating characteristic curve. Its consistency was assessed by calibration curve, decision curve, and Hosmer-Lemeshow testing goodness-of-fit. The multivariate model included factors such as male, BMI, smoking, diabetes, ursolic acid, and high-density lipoprotein cholesterol. The model validation showed that the consistency index was 0.714, and the external validation set had a consistency index of 0.741. The areas under the curve for the training and external validation sets were respectively 0.730 (95% CI: 0.681-0.779) and 0.770 (95%CI: 0.699-0.841). Nomogram calibration curves indicated intense calibration, and the results of the Hosmer-Lemeshow goodness-of-fit test indicated that χ² = 1.118, P = .572. The nomogram combining various risk factors can be used for individualized predictions of CSF patients and then facilitate prompt and specific treatment.

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.

Association of uric acid levels with cardiac syndrome X: A meta-analysis

Objective: The pathogenesis of elevated uric acid (UA) levels in patients with cardiac syndrome X (CSX) is unclear, and the results presented in recent papers on UA levels in patients with CSX are controversial. Therefore, we conducted a meta- analysis to assess the relationship between UA levels and CSX.

Methods: Three databases, including the Web of Science, EMBASE and PubMed, were systematically searched until January 2022. Fixed-effect and random-effects models were used to analyze the relationship between UA levels and CSX. Subgroup analysis and sensitivity analysis were also performed.

Results: Six studies involving 406 CSX patients and 267 non-CSX were included. Our results showed a significant relationship between UA levels and CSX, with a pooled SMD of 0.68 (95% CI 0.37 to 1.00; p < 0.0001). We also found a close relationship between UA levels and CSX for patients ≥ 55 years old (SMD:0.70, 95% CI: 0.41 to 0.99, p < 0.00001), for patients < 55 years old (SMD: 0.68, 95% CI: 0.25 to 1.12, p =0 .002), for women ≥ 60% (SMD: 0.77, 95% CI: 0.33 to 1.14, p =0 .0004), for women < 60% (SMD: 0.61, 95% CI:0.23 to 0.98, p =0 .001), for BMI ≥ 28 Kg/m² (SMD :0.61, 95% CI: 0.23 to 0.98, p =0 .001), for BMI < 28 Kg/m² (SMD:0.75, 95% CI: 0.31 to 1.19, p =0 .0009), for publication years ≥ 2012 (SMD :0.69, 95% CI: 0.23 to 1.15, p = 0.003), for publication years < 2012 (SMD:0.73, 95% CI:0.41 to 1.05, p < 0.00001), and for Turkey (SMD:0.75, 95% CI:0.38 to 1.11, p <.0001). Sensitivity analysis showed that the pooled results remained consistent after removing any one study or converting the random-effects model to fixed-effects model.

Conclusion: Our results indicated a strong association between high UA levels and CSX. However, more well-designed studies are needed to investigate whether early treatment of hyperuricemia can reduce the incidence of CSX.

Impact of hyperuricemia on coronary blood flow and in-hospital mortality in patients with acute myocardial infarction undergoing percutaneous coronary intervention

BACKGROUND

Although serum uric acid (UA) is considered as a risk factor for cardiovascular disease, few data exist regarding the relationship between hyperuricemia, coronary blood flow, and subsequent outcome in patients with acute myocardial infarction (AMI). The purpose of our study is to assess whether hyperuricemia is associated with suboptimal coronary flow and increased risk of mortality in patients with AMI after percutaneous coronary intervention (PCI).

METHODS

Using the Rural AMI registry data, 989 consecutive patients with AMI who underwent emergent PCI and had UA measurement at admission were analyzed. We defined hyperuricemia as serum UA ≥7.0 mg/dL in men and ≥ 6.0 mg/dL in women. The primary endpoint was suboptimal coronary flow, defined as post PCI Thrombosis In Myocardial Infarction flow grade ≤ 2. The secondary outcome was in-hospital mortality.

RESULTS

Hyperuricemia was found in 249 (25.2%) patients. Patients with hyperuricemia were more often complicated with cardiogenic shock compared with those without (16.9% vs. 7.4%, p < 0.001). In addition, the median high-sensitivity C-reactive protein was significantly higher in patients with hyperuricemia (0.18 mg/dL; IQR, 0.09-0.71 mg/dL) than in those without (0.14 mg/dL; IQR, 0.07-0.41 mg/dL, p < 0.05). Under these conditions, the prevalence of suboptimal coronary flow after PCI (17.3% vs. 10.1%, p < 0.05) and in-hospital mortality (10.8% vs. 3.6%, p < 0.001) were significantly higher in patients with hyperuricemia compared with those without. Multivariable logistic regression analysis revealed that hyperuricemia was significantly associated with suboptimal coronary flow [odds ratio (OR), 1.60; 95% confidence interval (CI), 1.02-2.49; p < 0.05] and in-hospital mortality (OR, 2.08; 95% CI, 1.05-4.12; p < 0.05).

CONCLUSIONS

Assessment of serum UA upon admission provides useful information for predicting suboptimal coronary flow and in-hospital mortality in patients with AMI undergoing PCI.

Evaluation of serum platelet-derived growth factor receptor-ß and brain-derived neurotrophic factor levels in microvascular angina

Objective:

Microvascular angina (MVA) is a coronary microcirculation disease. Research on microcirculatory dysfunction has revealed several biomarkers involved in the etiopathogenesis of MVA. Platelet-derived growth factor receptor β (PDGFR-β) and brain-derived neurotrophic factor (BDNF) are 2 biomarkers associated with microcirculation, particularly pericytes function. The aim of this study was to investigate the role of PDGFR-β and BDNF in MVA.

Methods:

Ninety-one patients (median age, 56 y; age range, 40–79 y; 36 men) with MVA and 61 control group subjects (median age, 52 y; age range, 38–76 y; 29 men) were included in the study. Serum concentrations of PDGFR-β and BDNF were measured with commercially available enzyme-linked immunosorbent assay kits.

Results:

PDGFR-β [2.82 ng/ml; interquartile range (IQR), 0.57–7.79 ng/ml vs. 2.27 ng/ml; IQR, 0.41–7.16 ng/ml; p<0.0005] and BDNF (2.41 ng/ml; IQR, 0.97–7.97 ng/ml vs. 1.92 ng/ml; IQR, 1.07–6.67 ng/ml; p=0.023) concentrations were significantly higher in patients with MVA compared with the controls. PDGFR-β correlated positively with age (r=0.26, p=0.001), low-density lipoprotein (r=0.18; p=0.02), and BDNF (r=0.47; p<0.001), and BDNF showed a significant positive correlation with age (r=0.20; p=0.01). In binary logistic regression analysis, high-sensitivity C-reactive protein, uric acid, and PDGFR-β values were found to be independent predictors of MVA.

Conclusion:

MVA is associated with higher PDGFR-β and BDNF levels. This association may indicate an abnormality in microvascular function. Future studies are required to determine the role of these biomarkers in the pathogenesis of MVA. (Anatol J Cardiol 2020; 24: 397-404)

Association of Meteorological Variables and Coronary Blood Flow

We aimed to assess the impact of meteorological variables on coronary blood flow (CBF). Coronary blood flow was evaluated using the thrombolysis in myocardial infarction frame count (TFC). The association of CBF with meteorological parameters such as temperature, relative humidity, total solar radiation, atmospheric pressure, wind velocity, and total sunshine duration were investigated as well as demographic, clinical, and laboratory characteristics. Assessment of 1206 patients (median age = 53 years, 723 females) revealed the presence of slow coronary flow (SCF) in 196 patients. Daily maximum temperature [odds ratio = 0.951, 95% confidence interval = 0.916-0.986, P = .007] was the only independent predictor of the presence of SCF, whereas systolic blood pressure (β = -0.139, P = .026), hematocrit level (β = 0.128, P = .044), and daily maximum temperature (β = -1.479, P = .049) were independent predictors of log10 (mean TFC). Findings of the present study suggest a role of meteorological parameters in CBF regulation.

Epicardial adipose tissue thickness is associated with myocardial infarction and impaired coronary perfusion

Objective:

Epicardial adipose tissue (EAT) is associated with the presence, severity and extent of atherosclerotic coronary artery disease (CAD) in addition to subclinical atherosclerosis. We investigated if EAT thickness is related to acute myocardial infarction in patients with CAD. We also searched for the association between EAT thickness and objective coronary flow and myocardial perfusion parameters such as Thrombolysis in Myocardial Infarction Frame count (TFC) and myocardial blush grade (MBG).

Methods:

Two-hundred consecutive patients with stable angina pectoris or acute coronary syndrome who were admitted to Ufuk University Faculty of Medicine, Dr Ridvan Ege Hospital cardiology department were included in this observational, cross-sectional study. EAT thickness was evaluated by conventional transthoracic echocardiography. Coronary angiography was performed to determine the coronary involvement and perfusion.

Results:

Mean EAT thicknesses were 5.4±1.9 mm, 6.3±1.8 mm, and 8.5±1.4 mm in the stable angina pectoris (SAP), unstable angina pectoris (USAP) and acute myocardial infarction groups, respectively (p<0.001). With increasing EAT thickness, TFC increases whereas mean MBG values decrease (for EAT thickness <5 mm, 5-7 mm, >7 mm; mean TFC: 21.6±2.2, 25.3±3.3 and 35.2±7.7; and MBG values: 2.98±0.14, 2.83±0.57 and 1.7±1.16, respectively; both p<0.001). Cut-off EAT value to predict AMI was identified as 7.8 mm (ROC analysis AUC: 0.876; p<0.001, 95% CI: 0.822-0.927). Sensitivity and specificity of EAT cut-off value 7.8 mm to predict AMI were 81.8% and 82.5% respectively.

Conclusion:

Increased EAT is associated with AMI and it may prove beneficial for choosing patients who would need more aggressive approach in terms of risk reduction using echocardiography which is a relatively cheap and readily available tool as a follow-up parameter.