Development Of Collateral Circulation Research Articles

Symptomology of celiac artery compression: Classifying patients by the degree of celiac artery stenosis and secondary changes in collateral branches on computed tomography angiogram

PurposeThis study aimed to analyze the correlation between the degree of celiac artery (CA) stenosis and the secondary changes in collateral branches in patients with CA compression (CAC) by CT and to classify patients by the combination of the two imaging features. MethodsPatients with CAC identified by contrast-enhanced CT from January 2012 to December 2013 were retrospectively enrolled and divided into the symptomatic group and asymptomatic group. CA stenosis was categorized as mild, moderate, or severe, and collateral circulation as invisible, visible, or prominent. The correlation between the imaging features was analyzed with Kendall’s Tau-b. Multivariate regression identified risk factors for symptomatic CAC. And patients were further classified into three subtypes (Type A to C) based on CA stenosis and collateral circulation. ResultsThis study included 150 patients (79 men, 71 women), with 49 (32.7 %) symptomatic. The collateral circulation classification correlated with the CA stenosis (Tau-b = 0.295, p < 0.001). And both imaging features were proven to be independent risk factors for the symptomatic CAC (all p < 0.05). Of the three subtypes of patients, only one patient with Type A (1/26 [3.8 %]) was symptomatic; a small proportion of patients with Type B (23/99 [23.2 %]) were symptomatic; and all patients with Type C (25/25 [100 %]) were symptomatic. ConclusionsThe development of collateral circulation is positively correlated with the degree of CA stenosis. Our proposed classification system based on the combination of the degree of CA stenosis and collateral circulation helps to identify patients with symptomatic CAC.

Correlation of left ventricular contractile function with the presence of collateral coronary circulation in non-reperfused acute myocardial infarction

To assess the association between coronary collateral circulation and ventricular contractile function in patients with non-reperfused acute myocardial infarction. A retrospective and descriptive clinical study was conducted on patients with ST-elevation myocardial infarction (STEMI) at a reference cardiovascular center, from January 2006 to December 2022. Coronary angiographies and echocardiograms were reviewed to evaluate coronary collateral circulation and ventricular function, respectively. Patients were divided into groups based on the presence of collateral circulation. Both groups were compared and mortality during the index hospitalization was analyzed. Out of a total of 14,985 patients with acute coronary syndrome, 8134 (54.3%) had the diagnosis of STEMI. We excluded 12,880, leaving a total of 2105 non-reperfused STEMI patients who underwent coronary angiography, revealing lesions. There were more patients without collateral circulation: 1547 (73.5%) vs. 558 (26.5%) (p = 0.025). Patients without collateral circulation had a higher left ventricular ejection fraction (median of 47% vs. 42%; p < 0.001). Mortality in patients with collateral circulation was higher compared to those without it (11.6% vs. 9.8%; p = 0.225), but statistical significance was not reached. Non-reperfused STEMI patients did not show protection from collateral circulation when assessing left ventricular systolic function. We did not find a difference in mortality compared to the population without development of collateral circulation.

Correlation between insulin resistance and coronary collateral circulation in patients with chronic total coronary occlusion

To explore the impact of diabetes on collateral circulation (CC) development in patients with chronic total coronary occlusion (CTO) and the underlying regulatory mechanism. This study was conducted among 87 patients with coronary heart disease (CHD), who had CTO in at least one vessel as confirmed by coronary angiography. Among them 42 patients were found to have a low CC level (Cohen-Rentrop grades 0-1) and 45 had a high CC level (grades 2-3). In the 39 patients with comorbid diabetes mellitus and 48 non-diabetic patients, insulin resistance (IR) levels were compared between the subgroups with different CC levels. The steady-state mode evaluation method was employed for calculating the homeostatic model assessment for insulin resistance index (HOMA-IR) using a mathematical model. During the interventional procedures, collateral and peripheral blood samples were collected from 22 patients for comparison of the metabolites using non-targeted metabolomics analysis. NT-proBNP levels and LVEF differed significantly between the patients with different CC levels (P<0.05). In non-diabetic patients, HOMA-IR was higher in low CC level group than in high CC level groups. Compared with the non-diabetic patients, the diabetic patients showed 63 upregulated and 48 downregulated metabolites in the collateral blood and 23 upregulated and 14 downregulated metabolites in the peripheral blood. The differential metabolites in the collateral blood were involved in aromatic compound degradation, fatty acid biosynthesis, and steroid degradation pathways; those in the peripheral blood were related with pentose phosphate metabolism, bacterial chemotaxis, hexanoyl-CoA degradation, glycerophospholipid metabolism, and lysine degradation pathways. The non-diabetic patients with a low level of CC had significant insulin resistance. The degradation pathways of aromatic compounds, fatty acid biosynthesis, and steroid degradation are closely correlated with the development of CC.

Elevated uric acid/albumin ratio as a predictor of poor coronary collateral circulation development in patients with non-ST segment elevation myocardial infarction.

Uric acid/albumin ratio (UAR) is a novel composite biomarker with superior predictive value for cardiovascular disease. To investigate the relationship between UAR and coronary collateral circulation (CCC) in patients with non-ST segment elevation myocardial infarction (NSTEMI). A total of 205 NSTEMI patients who underwent coronary arteriography with at least one major coronary stenosis, 95% were included. Patients were divided into two groups according to CCC development: poorly-developed CCC group (Rentrop 0-1) and well-developed CCC (Rentrop 2-3). Univariate analysis and logistic regression analysis were utilized to investigate the factors influencing adverse CCC formation in NSTEMI patients. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive value of UAR, C-reactive protein (CRP), uric acid, and albumin for patients with poorly developed CCC, and the area under the curve (AUC) was compared. The UAR values of NSTEMI patients were significantly higher in the poorly developed CCC group than those in the well-developed CCC group (10.19 [8.80-11.74] vs. 7.79 [6.28-9.55], p < .001). In the multiple logistic regression tests, UAR (odds ratio [OR]: 1.365, 95% confidence interval [CI]: 1.195-1.560, p < .001), CRP (OR: 1.149, 95% CI: 1.072-1.231, p < .001), and diabetes (OR: 2.924, 95% CI: 1.444-5.920, p = .003) were independent predictors of poorly developed CCC. The ROC curve analysis showed that the optimal cut-off value of UAR was 8.78 in predicting poorly developed CCC with a sensitivity of 76.8% and specificity of 62.4%, with the AUC of 0.737 (95% Cl: 0.668-0.805, p < .001). Elevated UAR may be an independent and effective biomarker for predicting poorly-developed CCC development in NSTEMI patients.

Oxidative Mechanisms and Cardiovascular Abnormalities of Cirrhosis and Portal Hypertension

In patients with portal hypertension, there are many complications including cardiovascular abnormalities, hepatorenal syndrome, ascites, variceal bleeding, and hepatic encephalopathy. The underlying mechanisms are not yet completely clarified. It is well known that portal hypertension causes mesenteric congestion which produces reactive oxygen species (ROS). ROS has been associated with intestinal mucosal injury, increased intestinal permeability, enhanced gut bacterial overgrowth, and translocation; all these changes result in increased endotoxin and inflammation. Portal hypertension also results in the development of collateral circulation and reduces liver mass resulting in an overall increase in endotoxin/bacteria bypassing detoxication and immune clearance in the liver. Endotoxemia can in turn aggravate oxidative stress and inflammation, leading to a cycle of gut barrier dysfunction → endotoxemia → organ injury. The phenotype of cardiovascular abnormalities includes hyperdynamic circulation and cirrhotic cardiomyopathy. Oxidative stress is often accompanied by inflammation; thus, blocking oxidative stress can minimize the systemic inflammatory response and alleviate the severity of cardiovascular diseases. The present review aims to elucidate the role of oxidative stress in cirrhosis-associated cardiovascular abnormalities and discusses possible therapeutic effects of antioxidants on cardiovascular complications of cirrhosis including hyperdynamic circulation, cirrhotic cardiomyopathy, and hepatorenal syndrome.

The Effect of Buerger Allen Exercise Towards Physical Health Performance of Peripheral Neuropathy Patients

Introduction: Peripheral neuropathy is a common microvascular complication in Diabetes Mellitus patients, with symptoms of tingling, numbness, pain in the feet, and disabilities in daily activities. Buerger Allen Exercise to stimulate the development of collateral circulation in the feet. The purpose of the study was to explain the effect of Buerger Allen’s Exercise on the physical health performance of diabetic neuropathy patients. Methods: The research design used an experimental one-group pre-test post-test design. Purposive sampling technique with inclusion criteria: male and female DM patients, with a long history of diabetes&gt; 5 years, undergoing treatment at the health center / other health services. Samples were taken in Krembangan Surabaya City with as many as 24 respondents. The independent variable was the Buerger Allen Exercise. The dependent variables were the physical health performance of diabetic neuropathy patients (peripheral oxygen saturation (StO2), Ankle-Brachial Index (ABI on the foot), and physical activity ability). The instruments used were an observation sheet for measurements of StO2, ABI, and physical ability. The research data were analyzed using the Paired t-test statistical test with a significance level of p &lt;0.05. Results: There are significant results Buerger Allen Exercise of Ankle-Brachial Index (p=0.0085) and physical activity ability (p=0.031), and no significant result of peripheral oxygen saturation (p=0.075). Conclusion: There is an effect of the Buerger Allen Exercise on the Ankle-Brachial Index and physical activity ability of diabetic neuropathy patients. Further research needs to examine Buerger’s exercise toward blood glucose levels and control factors that are related.

Effects of asymptomatic cerebral artery stenosis of anterior circulation and establishment of collateral circulation on cognition

ObjectiveThe purpose of this study is to investigate how cognition is affected by asymptomatic cerebral artery stenosis (CAS) of the anterior circulation and its related collateral circulation. Methods102 patients with CAS of the anterior circulation and 52 controls were enrolled from January 1, 2019 to June 30, 2022. Patients with CAS of anterior circulation were further divided into different subgroups according to the degree of stenosis, cerebral perfusion, and collateral circulation. A series of neuropsychological scales were used to evaluate the participant’s cognitive function, activities of daily living, and neuropsychiatric symptoms (such as memory, execution, psychomotor speed, etc.). The data were analyzed using T-test, F-test, chi-square test, rank sum test, and other statistical methods, moreover, the quantitative data were further examined for trends. The relationship between the degree of CAS, cerebral perfusion, collateral circulation, and the outcome of the cognitive test was investigated using Spearman correlation analysis. ResultsCompared to controls, there were severe impairments of global cognition, psychomotor speed/execution, memory, attention, activities of daily living, and more neuropsychiatric symptoms in patients with anterior circulation CAS (p < 0.05), and these impairments got worsened with the aggravation of CAS (p < 0.05). The global cognition, psychomotor speed / executive function, memory function, and daily living ability were impaired both in the cerebral perfusion-compensated group and decompensated group(p < 0.05), while there was no statistically significant difference between the two groups (p > 0.05). With the aggravation of CAS, the proportion of poor collateral formation increased, and this difference was statistically significant (P < 0.01). The degree of stenosis, cerebral perfusion, and collateral circulation establishment of anterior circulation CAS was correlated with global cognition, memory, psychomotor speed, execution, attention, activities of daily living, and neuropsychiatric symptoms (all p < 0.01). ConclusionCognitive impairment and the percentage of inadequate collateral circulation development rise as stenosis progresses in patients with anterior circulation CAS. The decline in global cognitive function was accompanied by impairments in psychomotor speed / executive function, memory function, attention, and daily living skills, as well as the aggravation of neuropsychiatric symptoms, especially in patients with impaired cerebral perfusion and poor collateral circulation formation.

Portal vein thrombosis: Before, during, and after liver transplant.

Portal vein thrombosis: Before, during, and after liver transplant.

Transdural Collateral Circulation Indicates Cerebral Ischemia in Moyamoya Disease

Moyamoya disease (MMD) is an idiopathic occlusive cerebrovascular disorder. The development of collateral circulation originates from the dural and pial collaterals. Currently, the clinical significance of transdural collateral in MMD has not been established. We sought to study the relationship between transdural collateral circulation and the side of relative cerebral ischemia in MMD. Data from MMD patients were collected at Xiangya Hospital from January 2016 to April 2022. A collateral circulation grading system with scores was established, the dominant side of transdural collateral with a higher point. Cerebral perfusion was used to identify the side of relative cerebral ischemia. A total of 102 patients were recruited. Results of digital subtraction angiography showed that 74 (72.5%) patients had transdural collaterals. The transdural collaterals were more common in patients with infarctions than in those with headaches or transient ischemic attacks (P= 0.0074). The dominant side for the formation of transdural collateral circulation was more easily found at the side of relative cerebral ischemia (P < 0.0001). Additionally, the side of the brain with a higher score of transdural collaterals was more likely to experience relative cerebral ischemia (P < 0.0001). There was no significant difference in the formation of transdural collateral circulation between ischemic and hemorrhagic MMD patients. Transdural collateral circulation was common in MMD patients. The transdural collaterals were associated with the occurrence of infarction. Transdural collaterals were well established on the cerebral ischemic side, which indicated higher ischemic levels in the ipsilateral than contralateral side.

Collaterals in congenital heart disease: when and how to treat?

The development of collateral circulation is not that rare in patients with congenital heart defects. These collaterals can affect cardiovascular hemodynamics and cause systemic arterial desaturation, which arises the question whether these should be closed. To date, few if any reports have been published on the therapeutic management of collaterals in adult patients with congenital heart disease in heart failure (HF). The focus of this article is to provide a pragmatic approach in the assessment of collateral circulation of the patient with HF. By considering the underlying hemodynamics and overall effects of the collateral circulation, we aim to provide a practical tool useful in clinical decision making. The paper highlights mainly the systemic venous to systemic venous collaterals, systemic venous to pulmonary venous (or pulmonary venous atrium) collaterals, and pulmonary arterio-venous malformations. Systemic venous anomalies are frequent and reported in 20% to 40% of patients who underwent Glenn or Fontan procedure. A reduction in effective pulmonary blood flow, coupled with increasing oxygen demands with growth, as well as a pressure difference between the higher pressure caval venous system and lower pressure atria (so called decompressing collaterals) are potential causes of collateral formation. Whether angiogenesis de novo or reappearance of embryological venous channels is responsible for collateral formation remains to be elucidated.

The impact of the apelinergic system in coronary collateral formation.

This study aims to examine the relationship between the development of coronary collateral circulation and serum elabela levels. Between January 2020 and December 2021, a total of 50 control individuals (29 males, 21 females; mean age: 63.2±10.0 years; range, 52 to 73 years) with no significant coronary artery disease as confirmed by angiography (Group 1) and 100 patients (55 males, 45 females; mean age: 66.6±9.6 years; range, 56 to 75 years) with coronary artery disease were included. The patients were further divided into two equal groups according to the Rentrop classification as poor (Group 2) and good coronary collateral circulation (Group 3). All groups were compared in terms of several parameters, particularly serum elabela levels. Serum elabela levels were found to be statistically higher in the group with good collateral than the other groups (p<0.05). Low serum elabela levels increased the risk of developing weak collaterals by 2.43 times. The elabela protein is directly related to good collateral development and can be considered a potential agent for treatment.

Ultrasound and magnetic resonance of extrinsic stenosis and hypoplasia of internal jugular veins

Highlights. Ultrasound and MR venography of internal jugular veins in case of unilateral cerebellar hypoplasia or extrinsic stenosis enables noninvasively and without contrast agents differentiation of these conditions due to local and region-specific indicators, including the area and velocity of blood flow, arterial-venous balance, visualization of low blood flow, compression factor, and the overall clinical picture of venous network of the neck remodeling and the development of collateral circulation.Aim. To compare the visual and hemodynamic characteristics of ultrasound and magnetic resonance venography of extrinsic stenosis and hypoplasia of internal jugular veins (IJV).Methods. Ultrasound and magnetic resonance (MR) venography were performed in 47 patients with extrinsic stenosis and 23 patients with hypoplasia of one of internal jugular veins, and in the control group (30 patients).Results. In case of obvious vein compression and deformation and local stenosis (65% on average), there is a decrease in the vein cross-sectional area by 2 times compared with the contralateral vein, the blood flow velocity in the stenotic vein in acute cases increases (on average, up to 45 cm/s), and in chronic cases it significantly (p = 0.00001) decreases (to 13 cm/s on average). The criteria for hypoplasia are the small caliber of the vein (on average 0.22 cm², within the range of 0.13–0.46 cm²) throughout its entire length - with the cross-sectional area not exceeding that of the common carotid artery, and the vein being 4 times smaller than IJV on contralateral side, as well as a significant (p = 0.0006) velocity increase on the contralateral side (on average 40.9±12.52 cm/s) with normal velocity in the hypoplastic vein. Ultrasound assessment of the arterial-venous balance (AVB) makes it possible to evaluate the contribution of each IJV to the outflow of venous blood from the brain separately. From the hypoplastic side it was only 11.01±6.72%, and from the stenotic side it was 18.22±17 42% on average, which is significantly (p = 0.000001) below the norm, but does not allow us to differentiate these conditions. The total AVB for IJVs on both sides was within normal values (65–85%), and the absence of a pronounced expansion of the vertebral veins during MR venography confirms their insignificant role in the compensatory mechanisms of ensuring adequate outflow of venous blood from the brain in cases of unilateral hypoplasia and extrinsic stenosis of IJV.Conclusion. Ultrasound and MR venography of internal jugular veins in cases of unilateral hypoplasia or extrinsic stenosis enable noninvasively and without contrast agents differentiation of these conditions due to local and region-specific indicators, including the area and velocity of blood flow, arterial-venous balance, visualization of low blood flow, compression factor, and the overall clinical picture of venous network of the neck remodeling and the development of collateral circulation.

The association of serum uric acid/albumin ratio with the development of coronary collateral circulation in patients with chronic total occluded coronary arteries.

Introduction: Coronary collateral circulation (CCC) develops in chronic total occluded (CTO) vessels and protects the myocardium against ischemia in addition to the improvement of cardiac functions. Poor CCC is related to adverse cardiac events as well as poor prognosis. Serum uric acid/albumin ratio (UAR) has emerged as a novel marker associated with poor cardiovascular outcomes. We aimed to investigate whether there was an association between UAR and poor CCC in CTO patients. Methods: This study was comprised of 212 patients with CTO (92 with poor CCC and 120 with good CCC). All patients were graded based on Rentrop scores to poor CCC (Rentrop scores 0 and 1) and good CCC (Rentrop scores 2 and 3). Results: Poor CCC patients had higher frequencies of diabetes mellitus, triglyceride levels, Syntax and Gensini scores, uric acid, and UAR and lower lymphocyte, high-density lipoprotein cholesterol, and ejection fraction when compared to good CCC patients. UAR was an independent predictor of poor CCC in CTO patients. Furthermore, UAR had a better discriminative ability for patients with poor CCC from good CCC compared to serum uric acid and albumin. Conclusion: Based on the results of the study, the UAR could be used to detect poor CCC in CTO patients.

The relationship between neutrophil-to-lymphocyte ratio and cerebral collateral circulation in patients with symptomatic severe intracranial artery stenosis or occlusion

BackgroundThe neutrophil/lymphocyte ratio (NLR) has been considered a prognostic indicator for determining the systemic inflammatory response and atherosclerosis. We aimed to determine the relationship between NLR and the development of cerebral collateral circulation in patients with symptomatic severe stenosis or occlusion of intracranial arteries. MethodsAll patients underwent digital subtraction angiography (DSA) within 14 days of admission and were divided into a group with good collateral circulation (77 patients) and a group with poor collateral circulation (86 patients) according to the DSA collateral compensation grading method. Apo B, total cholesterol, LDL, and Neutrophil count in the poor side branch group were significantly higher than in the good side branch group. Multifactorial analysis showed that high NLR levels were a valid predictor of poor collateral circulation in patients with symptomatic severe intracranial artery stenosis or occlusion. Spearman correlation analysis showed that the size of the collateral branch score was negatively correlated with NLR (r = −0.509, P < 0.001) and cholesterol content (r = −0.249, P = 0.002). NLR predicted poor collateral circulation with an AUC of 0.620 (sensitivity 66.7 %, specificity 61.3 %, 95 % CI = 0.517–0.723,P < 0.05). ConclusionWe demonstrate a correlation between NLR levels and the development of collateral circulation in the brain in patients with symptomatic severe stenosis or occlusion of the intracranial arteries.

A RARE CASE OF HISTOPLASMA CAUSING OBLITERATION OF THE SUPERIOR VENA CAVA AND SUBSEQUENT DEVELOPMENT OF COLLATERAL CIRCULATION

A RARE CASE OF HISTOPLASMA CAUSING OBLITERATION OF THE SUPERIOR VENA CAVA AND SUBSEQUENT DEVELOPMENT OF COLLATERAL CIRCULATION

A Rare Case of ALCAPA in Adult Asymptomatic Patient and Unusual Collateral Circulation: A Case Report

Anomalous Origin of the Left Coronary Artery from Pulmonary Artery (ALCAPA) syndrome is a rare congenital anomaly where the left main coronary artery arises from the pulmonary artery (PA) and the right coronary artery (RCA) originates normally from the aorta. The rapid decrease in pulmonary vascular resistance (PVR) soon after birth reverses the blood flow to the PA resulting in a left to right shunt and severe left ventricle (LV) ischemia. Left untreated, this congenital anomaly is associated with premature death. Rarely, some patients can survive to adult age due to development of collateral circulation usually from an ecstatic RCA. Most adult patients with ALCAPA die at mean age of 35 years. Very few cases were reported in the literature to survive until late 40s or 50s. We present the case of ALCAPA in an asymptomatic 54-year-old woman who found to have unusual collateral circulation justifying the absence of significant symptoms. Our patient underwent surgical correction with good results. We also review cases of ALCAPA that has been reported in the literature and we summarize treatment strategies. Learning objective: recognition of ALCAPA as one of coronary anomalies in adults even in asymptomatic individuals and recognition of the best diagnostic modality and the optimal management according to available literature.

Efficacy and safety of endovascular therapy for delayed hepatic artery post-pancreatectomy hemorrhage: development of extrahepatic collateral circulation and complications of post endovascular therapy

BackgroundEndovascular therapy (ET) for delayed hepatic artery post-pancreatectomy hemorrhage (HA-PPH) may require complete hepatic artery occlusion (HAO). Nonetheless, the development of extrahepatic collateral circulation (EHC) and the relationship between radiological factors (EHC, portal vein stenosis, and HAO) and adverse hepatic events after ET remain unclear. This study aimed to evaluate the efficacy and safety of ET for delayed PPH and examine the development of EHC.MethodsA total of 19 ET cases for delayed HA-PPH were reviewed. Hepatic adverse events, portal vein stenosis, HAO, and mortality rate after ET were evaluated. Moreover, EHC from the left gastric artery (LGA), right inferior phrenic artery (RIPA), left inferior phrenic artery (LIPA), right internal thoracic artery (RITA), left internal thoracic artery (LITA), renal artery (RA), omental artery (OA), intercostal artery (IA), and branch of superior mesenteric artery (BSMA) was assessed using angiogram and computed tomography angiography (CTA).ResultsAll cases were successfully treated using transcatheter arterial embolization (n = 17) and stent-graft placement (n = 2) without mortality. EHC from the LGA (8/19), RIPA (10/19), LIPA (4/19), and RITA (3/19) was observed on post-ET CTA. The incidence of hepatic adverse events was significant in the group with both HAO and portal vein stenosis (p < 0.001) and absence of EHC from LIPA and RITA (p < 0.05).ConclusionET for delayed HA-PPH might be effective and safe. While avoiding both HAO and portal vein stenosis is important, the development of EHCs from LIPA and RITA may prevent hepatic adverse events after ET.

Obstructive sleep apnea and coronary artery disease: An unholy nexus or a holy alliance?

Coronary artery disease (CAD) is a significant cause of morbidity and mortality globally, and hypertension, dyslipidemia, diabetes mellitus, and smoking are major cardiovascular (CV) risk factors. Obstructive sleep apnea (OSA) and CAD share an exciting relationship, and recently, OSA has emerged as a non-traditional CV risk factor. OSA is characterized by episodic sleep state-dependent collapse of the upper airway, resulting in periodic reductions or cessations in ventilation, with consequent hypoxia, hypercapnia, or arousals from sleep. The oxidative stress and vascular inflammation resulting from the nocturnal hypoxia followed by reoxygenation cycles predispose the patients to the development of atherosclerotic cardiovascular disease (CVD). Untreated OSA is associated with long-term health consequences, including CVD, metabolic disorders, cognitive impairment, and depression. Paradoxically, some recent studies have reported that patients with OSA may suffer less severe CAD due to the development of collateral circulation due to repetitive hypoxia experienced due to OSA.

Cytokine storm: behind the scenes of the collateral circulation after acute myocardial infarction.

At least 17 million people die from acute myocardial infarction (AMI) every year, ranking it first among causes of death of human beings, and its incidence is gradually increasing. Typical characteristics of AMI include acute onset and poor prognosis. At present, there is no satisfactory treatment, but development of coronary collateral circulation (CCC) can be key to improving prognosis. Recent research indicates that the levels of cytokines, including those related to promoting inflammatory responses and angiogenesis, increase after the onset of AMI. In the early phase of AMI, cytokines play a vital role in inducing development of collateral circulation. However, when myocardial infarction is decompensated, cytokine secretion increases greatly, which may induce a cytokine storm and worsen prognosis. Cytokines can regulate the activation of a variety of signal pathways and form a complex network, which may promote or inhibit the establishment of collateral circulation. We searched for published articles in PubMed and Google Scholar, employing the keyword “acute myocardial infarction”, “coronary collateral circulation” and “cytokine storm”, to clarify the relationship between AMI and a cytokine storm, and how a cytokine storm affects the growth of collateral circulation after AMI, so as to explore treatment methods based on cytokine agents or inhibitors used to improve prognosis of AMI.

Evaluation of cerebral collateral status using computed tomography angiography in ischemic stroke: review of manual and automated methods

In ischemic stroke, the condition of cerebral collateral circulation is one of the key factors determining the outcome. Digital subtraction angiography is considered the gold standard of evaluation of cerebral collateral circulation. However, computed tomography angiography is the most widely used method characterized by high level of conformity with subtraction angiography. Currently, several scales of visual evaluation of collateral circulation development in images obtained by computed tomography angiography are used. The scales describe the territory of stroke-associated cerebral artery, as well as details of various areas of the territory. The association between the score and severity of neurological deficit and volume of cerebral ischemia was demonstrated in numerous studies. However, consensus on the most reliable method of description of cerebral collateral status has not been reached. Use of modern methods of processing of medical images and artificial intelligence allowed to make a significant step towards automatization of collateral status evaluation with such benefits as high processing speed and resistance to subjective opinion. Despite low number of studies on this subject, implementation of automated solutions has already showed its effectiveness. In this review, scales for manual evaluation of cerebral collateral status are considered, their reliability is described, and current approaches to automated evaluation of collateral circulation in ischemic stroke are presented.