LncRNA-LncDACH1 mediated phenotypic switching of smooth muscle cells during neointimal hyperplasia in male arteriovenous fistulas.

Arteriovenous fistulas (AVFs) are the most common vascular access points for hemodialysis (HD), but they have a high incidence of postoperative dysfunction, mainly due to excessive neointimal hyperplasia (NIH). Our previous studies have revealed a highly conserved LncRNA-LncDACH1 as an important regulator of cardiomyocyte and fibroblast proliferation. Herein, we find that LncDACH1 regulates NIH in AVF in male mice with conditional knockout of smooth muscle cell-specific LncDACH1 and in male mice model of AVF with LncDACH1 overexpression by adeno-associated virus. Mechanistically, silence of LncDACH1 activates p-AKT through promoting the expression of heat shock protein 90 (HSP90) and serine/arginine-rich splicing factor protein kinase 1 (SRPK1). Moreover, LncDACH1 is transcriptionally activated by transcription factor KLF9 that binds directly to the promoter region of the LncDACH1 gene. In this work, during AVF NIH, LncDACH1 is downregulated by KLF9 and promotes NIH through the HSP90/ SRPK1/ AKT signaling axis.

Personalised stroke evaluation and management: tailoring individualised patient care for hereditary haemorrhagic telangiectasia.

SummaryHereditary haemorrhagic telangiectasia (HHT) has an estimated prevalence of 1 in 5000-8000 individuals globally with pulmonary arteriovenous malformations (PAVMs) affecting approximately 15%-50% of HHT patients. Ischaemic stroke is a known complication of PAVMs that affects ≤30% of patients with PAVMs. Studies have shown that patients with PAVMs have ischaemic stroke a decade earlier than routine stroke. The predominant mechanism of ischaemic stroke in HHT patients is paradoxical embolism due to PAVMs, but most HHT-related PAVMs are asymptomatic. Additionally, HHT is often underdiagnosed in patients and poses a challenge to physicians due to its rarity. We present a case of a patient with ischaemic stroke who was subsequently diagnosed with HHT and found to have a PAVM on further evaluation. This case highlights the importance of using an individualised patient-centred stroke evaluation and screening for PAVMs in patients who had a stroke with possible or suspected HHT and definite HHT.

Surgical management of multiple coronary artery to coronary sinus fistulas with giant left circumflex artery and multivalvular infective endocarditis.

Coronary artery fistula (CAF) is characterized as a congenital or acquired abnormal communication between a coronary artery and any of the four chambers of the heart (coronary-cameral fistula) or great vessels (coronary arteriovenous fistula) bypassing the capillaries within myocardium. CAF is a rare disease, challenging to diagnose and treat depending on the anatomical location and type of the fistula and accompanying diseases. This study aims to report a case with multiple coronary artery to coronary sinus (CS) fistulas with giant left circumflex artery and multivalvular infective endocarditis.

Acute myocardial infarction due to giant coronary artery aneurysm and arteriovenous fistula: a challenging case report and review of the literature.

BACKGROUND: A coronary artery aneurysm (CAA) is an abnormal dilation of a coronary artery segment often accompanied by coronary artery fistula (CAF), leading to communication between a coronary artery and a cardiac chamber or a part of the coronary venous system. Both CAAs and CAFs can present with symptoms and signs of myocardial ischemia and infarction. CASE PRESENTATION: We describe the case of a 46-year-old woman with non-ST-elevation myocardial infarction (NSTEMI) caused by a "giant" CAA. Various imaging modalities revealed a thrombus-containing aneurysm located at the right-posterior cardiac border, with established arteriovenous communication with the distal part of left circumflex artery (LCx). After initial treatment with dual antiplatelet therapy, a relapse of pain was reported along with a new increase in troponin levels, electrocardiographic abnormalities, reduced left ventricular ejection fraction (LVEF) and thrombus enlargement. Surgical excision of the aneurysm was favored, revealing its true size of 6 cm in diameter. Τhe aneurysm was excised without complications. The patient remained asymptomatic during follow-up. CONCLUSIONS: Management of rare entities such as "giant" CAAs and CAFs can be challenging. Cases such as this can serve as precedents to facilitate treatment plans and develop consistent recommendations, emphasizing the importance of personalized strategies for future patients.

Mitochondrial targeted catalase improves muscle strength following arteriovenous fistula creation in mice with chronic kidney disease.

Hand dysfunction is a common observation after arteriovenous fistula (AVF) creation for hemodialysis access and has a variable clinical phenotype; however, the underlying mechanism responsible is unclear. Grip strength changes are a common metric used to assess AVF-associated hand disability but has previously been found to poorly correlate with the hemodynamic perturbations post-AVF placement implicating other tissue-level factors as drivers of hand outcomes. In this study, we sought to test if expression of a mitochondrial targeted catalase (mCAT) in skeletal muscle could reduce AVF-related limb dysfunction in mice with chronic kidney disease (CKD). Male and female C57BL/6J mice were fed an adenine-supplemented diet to induce CKD prior to placement of an AVF in the iliac vascular bundle. Adeno-associated virus was used to drive expression of either a green fluorescent protein (control) or mCAT using the muscle-specific human skeletal actin (HSA) gene promoter prior to AVF creation. As expected, the muscle-specific AAV-HSA-mCAT treatment did not impact blood urea nitrogen levels (P = 0.72), body weight (P = 0.84), or central hemodynamics including infrarenal aorta and inferior vena cava diameters (P > 0.18) or velocities (P > 0.38). Hindlimb perfusion recovery and muscle capillary densities were also unaffected by AAV-HSA-mCAT treatment. In contrast to muscle mass and myofiber size which were not different between groups, both absolute and specific muscle contractile forces measured via a nerve-mediated in-situ preparation were significantly greater in AAV-HSA-mCAT treated mice (P = 0.0012 and P = 0.0002). Morphological analysis of the post-synaptic neuromuscular junction uncovered greater acetylcholine receptor cluster areas (P = 0.0094) and lower fragmentation (P = 0.0010) in AAV-HSA-mCAT treated mice. Muscle mitochondrial oxidative phosphorylation was not different between groups, but AAV-HSA-mCAT treated mice had lower succinate-fueled mitochondrial hydrogen peroxide emission compared to AAV-HSA-GFP mice (P < 0.001). In summary, muscle-specific scavenging of mitochondrial hydrogen peroxide significantly improves neuromotor function in mice with CKD following AVF creation.

Computational fluid-structure interaction analysis of the end-to-side radio-cephalic arteriovenous fistula.

BACKGROUND AND OBJECTIVE: In the current work, we present a descriptive fluid-structure interaction computational study of the end-to-side radio-cephalic arteriovenous fistula. This allows us to account for the different thicknesses and elastic properties of the radial artery and cephalic vein. METHODS: The core of the work consists in simulating different arteriovenous fistula configurations obtained by virtually varying the anastomosis angle, i.e. the angle between the end of the cephalic vein and the side of the radial artery. Since the aim of the work is to understand the blood dynamics in the very first days after the surgical intervention, the radial artery is considered stiffer and thicker than the cephalic vein. RESULTS: Our results demonstrate that both the diameter of the cephalic vein and the anastomosis angle play a crucial role to obtain a blood dynamics without re-circulation regions that could prevent fistula failure. CONCLUSIONS: When an anastomosis angle close to the perpendicular direction with respect to the radial artery is combined with a large diameter of the cephalic vein, the recirculation regions and the low Wall Shear Stress (WSS) zones are reduced. Conversely, from a structural point of view, a low anastomosis angle with a large diameter of the cephalic vein reduces the mechanical stress acting on the vessel walls.

Unusual origins of cardiac insufficiency: a case of iliac arteriovenous fistula post-spinal disc surgery.

In this case report, we present the unique and intriguing case of a 57-year-old man who experienced exertional palpitations and shortness of breath for 5 years. He was diagnosed with idiopathic heart failure three years ago, leading to diuretic treatment. Physical examination revealed notable left lower extremity swelling, severe varicose veins, and cardiac murmurs. Echocardiography showed significant cardiac enlargement and severe functional mitral and tricuspid valve regurgitation. Computed tomography (CT) imaging uncovered a 10 mm left common iliac arteriovenous fistula, causing abnormal early filling of the inferior vena cava (IVC) and marked IVC dilation. Open surgical repair of the arteriovenous fistula resulted in symptom relief and improved cardiac function. This case underscores the importance of considering unusual causes in heart failure patients and highlights the value of early diagnosis and intervention in complex cardiac-vascular interactions.

[Ischemic stroke due to paradoxical embolism through pulmonary arteriovenous malformation in a young patient]. / ACV isquémico debido a embolia paradojal a través de malformación arteriovenosa pulmonar en paciente joven.

Paradoxical embolism due to an isolated pulmonary arteriovenous malformation (PAVM) is a rare cause of ischemic stroke. PAVMs are abnormal high-flow connections between pulmonary arteries and veins, diverting deoxygenated blood into the systemic circulation and they represent a less common source of paradoxical embolisms, especially in young individuals. Endovascular embolization is the preferred treatment for clinically significant PAVMs. We present the case of a 34-year-old woman with a left thalamic ischemic stroke. Severe contrast passage was detected in cerebral arteries through transcranial Doppler. Intracardiac ultrasound did not reveal a patent foramen ovale, prompting further investigation with pulmonary CT angiography, confirming the presence of PAVM. The patient underwent successful endovascular treatment. It is essential to consider PAVM in the etiological diagnosis of ischemic stroke, especially in young patients with signs of abnormal right-to-left communication. Periodic follow-up imaging is recommended to assess potential recurrence or changes in PAVM, emphasizing the importance of appropriate management of these malformations.

La embolia paradojal debido a una malformación arteriovenosa pulmonar (MAVP) aislada es una causa infrecuente de accidente cerebrovascular (ACV) isquémico. Las MAVP son conductos anómalos de alta circulación entre arterias y venas pulmonares, desviando sangre desoxigenada hacia la circulación sistémica y representan una fuente menos común de embolias paradojales, especialmente en personas jóvenes. La embolización endovascular es el tratamiento preferido para MAVP clínicamente significativas. Presentamos el caso de una mujer de 34 años con ACV isquémico talámico izquierdo. Se detectó pasaje de burbujas "en cortina" en arterias cerebrales mediante Doppler transcraneal. En ecografía intracardíaca no se encontró foramen oval permeable, motivo por el cual se avanzó con realización de angiotomografía pulmonar, la cual confirmó la presencia de MAVP. La paciente recibió tratamiento endovascular exitoso. Es esencial considerar la MAVP en el diagnóstico etiológico del ACV isquémico, especialmente en pacientes jóvenes con signos de comunicación anormal de derecha a izquierda. Se recomienda un seguimiento periódico mediante imágenes para evaluar la posible recurrencia o cambios en la MAVP, resaltando la importancia del manejo adecuado de estas malformaciones.

The role of surgical disconnection for posterior fossa pial arteriovenous fistulas and dural fistulas with pial supply: an illustrative case series.

BACKGROUND: Pial arteriovenous fistulas (pAVFs) are rare vascular malformations characterized by high-flow arteriovenous shunting involving a cortical arterial supply directly connecting to venous drainage without an intermediate nidus. Dural arteriovenous fistulas (dAVFs) can infrequently involve additional pial feeders which can introduce higher flow shunting and increase the associated treatment risk. In the posterior fossa, arteriovenous fistula (AVF) angioarchitecture tends to be particularly complex, involving either multiple arterial feeders-sometimes from both dural and pial origins-or small caliber vessels that are difficult to catheterize and tend to be intimately involved with functionally critical brainstem or upper cervical cord structures. Given their rarity, published experience on microsurgical or endovascular treatment strategies for posterior fossa pAVFs and dAVFs with pial supply remains limited. METHODS: Retrospective chart review from 2019-2023 at a high-volume center identified six adult patients with posterior fossa pAVFs that were unable to be fully treated endovascularly and required microsurgical disconnection. These cases are individually presented with a technical emphasis and supported by comprehensive angiographic and intraoperative images. RESULTS: One vermian (Case 1), three cerebellopontine angle (Cases 2-4) and two craniovertebral junction (Cases 5-6) posterior fossa pAVFs or dAVFs with pial supply are presented. Three cases involved mixed dural and pial arterial supply (Cases 1, 4, and 6), and one case involved a concomitant microAVM (Case 2). Endovascular embolization was attempted in four cases (Cases 1-4): The small caliber and tortuosity of the main arterial feeder prevented catheterization in two cases (Cases 1 and 3). Partial embolization was achieved in Cases 2 and 4. In Cases 5 and 6, involvement of the lateral spinal artery or anterior spinal artery created a prohibitive risk for endovascular embolization, and surgical clip ligation was pursued as primary management. In all cases, microsurgical disconnection resulted in complete fistula obliteration without evidence of recurrence on follow-up imaging (mean follow-up 27.1 months). Two patients experienced persistent post-treatment sensory deficits without significant functional limitation. CONCLUSIONS: This illustrative case series highlights the technical difficulties and anatomical limitations of endovascular management for posterior fossa pAVFs and dAVFs with pial supply and emphasizes the relative safety and utility of microsurgical disconnection in this context. A combined approach involving partial preoperative embolization-when the angioarchitecture is permissive-can potentially decrease surgical morbidity. Larger studies are warranted to better define the role for multimodal intervention and to assess associated long-term AVF obliteration rates in the setting of pial arterial involvement.

Retrospective analysis of predictive factors for AVF dysfunction in patients undergoing MHD.

To construct an early clinical prediction model for AVF dysfunction in patients undergoing Maintenance Hemodialysis (MHD) and perform internal and external verifications. We retrospectively examined clinical data from 150 patients diagnosed with MHD at Hefei Third People's Hospital from January 2014 to June 2023. Depending on arteriovenous fistula (AVF) functionality, patients were categorized into dysfunctional (n = 62) and functional (n = 88) cohorts. Using the least absolute shrinkage and selection operator(LASSO) regression model, variables potentially influencing AVF functionality were filtered using selected variables that underwent multifactorial logistic regression analysis. The Nomogram model was constructed using the R software, and the Area Under Curve(AUC) value was calculated. The model's accuracy was appraised through the calibration curve and Hosmer-Lemeshow test, with the model undergoing internal validation using the bootstrap method. There were 11 factors exhibiting differences between the group of patients with AVF dysfunction and the group with normal AVF function, including age, sex, course of renal failure, diabetes, hyperlipidemia, Platelet count (PLT), Calcium (Ca), Phosphorus, D-dimer (D-D), Fibrinogen (Fib), and Anastomotic width. These identified factors are included as candidate predictive variables in the LASSO regression analysis. LASSO regression identified age, sex, diabetes, hyperlipidemia, anastomotic diameter, blood phosphorus, and serum D-D levels as 7 predictive factors. Unconditional binary logistic regression analysis revealed that advanced age (OR = 4.358, 95% CI: 1.454-13.062), diabetes (OR = 4.158, 95% CI: 1.243-13.907), hyperlipidemia (OR = 3.651, 95% CI: 1.066-12.499), D-D (OR = 1.311, 95% CI: 1.063-1.616), and hyperphosphatemia (OR = 4.986, 95% CI: 2.513-9.892) emerged as independent risk factors for AVF dysfunction in MHD patients. The AUC of the predictive model was 0.934 (95% CI: 0.897-0.971). The Hosmer-Lemeshow test showed high consistency between the model's predictive results and actual clinical observations (χ2 = 1.553, P = .092). Internal validation revealed an AUC of 0.911 (95% CI: 0.866-0.956), with the Calibration calibration curve nearing the ideal curve. Advanced age, coexisting diabetes, hyperlipidemia, blood D-D levels, and hyperphosphatemia are independent risk factors for AVF dysfunction in patients undergoing MHD.

Effectiveness of the Eutectic Mixture of Local Anaesthetics Cream in the Management of Arteriovenous Fistula Needle Insertion Pain in Patients Undergoing Haemodialysis.

This review aimed to assess the effectiveness of the eutectic mixture of local anaesthetics (EMLA) cream in the management of arteriovenous fistula (AVF) needle insertion pain in adult patients undergoing haemodialysis (HD) compared with other alternative interventions. The main search was conducted in November 2020 and updated in December 2021. In the search strategy, keywords and synonyms were used and multiple databases were searched with no date limitation to ensure a comprehensive search that would yield all studies relevant to the review and minimise location bias. A total of 209 studies were found in this search and filtered. After filtering through these studies, only five studies were finally included in the review. EMLA-cream was found to be effective in reducing AVF needle insertion pain among adult patients undergoing HD. Despite EMLA cream's effectiveness in reducing HD needle insertion pain and its fewer side effects, the findings of the included studies should be interpreted with caution, as there are some limitations, and further research is required.

Factors Affecting the Early Maturation of Arteriovenous Fistulae Created at a Tertiary Centre in Oman.

Objectives: This study aimed to determine the risk factors associated with the failure of arteriovenous fistulae (AVF) maturation. Methods: This retrospective cohort study was conducted from January 2014 to December 2018 in Sultan Qaboos University Hospital, Muscat, Oman. Patients were followed-up 3 months after surgery, and their electronic medical records were accessed for demographic and clinical data. Univariate analysis was used to determine the risk factors associated with early AVF maturation and multivariant analysis was used to determine the predictive factors for AVF failure. Results: A total of 269 patients were included. Female gender was a significant factor affecting AVF maturity (P = 0.049), while age (P = 0.626), diabetes (P = 0.954), hypertension (P = 0.378), dyslipidaemia (P = 0.907), coronary artery disease (P = 0.576), cerebrovascular accident (P = 0.864), congestive heart failure (P = 0.685), previous central venous catheterisation (P = 0.05), fistula type (P = 0.863) and fistula site (P = 0.861) did not affect AVF maturation. Binary logistic regression showed that all the risk factors were insignificant. Failure of early AVF maturation affected 11.5% in the cohort. Conclusion: This study found that the proportion of early AVF maturation at our hospital is at par with that in the international literature. Failure of AVF maturation was significantly associated with the female gender. These findings can help nephrologists and vascular surgeons prognosticate AVF maturation rates. However, a larger study is needed for definitive conclusions.

Ultrasound-guided high-intensity focused ultrasound ablation for uterine arteriovenous fistula: a case series.

PURPOSE: To evaluate the efficacy and safety of high-intensity focused ultrasound (HIFU) ablation in the treatment of uterine arteriovenous fistula (UAVF). MATERIALS AND METHODS: This case series included three patients diagnosed with acquired UAVF. All patients underwent routine laboratory tests, electrocardiography (ECG), chest X-ray, ultrasound, and pelvic contrast-enhanced magnetic resonance imaging (MRI). HIFU treatment was performed under sedation and analgesia using a Model JC Focused Ultrasound Tumor Therapeutic System (made by Chongqing Haifu Medical Technology Co. Ltd., China) with a B mode ultrasound device for treatment guidance. The treatment time, sonication power, sonication time, and complications were recorded. Follow-up evaluations were scheduled at 1-, 3-, 6-, and 12-month to assess symptom improvement and evaluate the post-treatment imaging. RESULTS: All patients completed HIFU treatment in a single session without any major complication. All patients complained of mild lower abdominal and sacrococcygeal pain. Typically, no special treatment is required. Following HIFU treatment, there was a significant relief in clinical symptoms, particularly abnormal uterine bleeding. Ultrasound examinations conducted one month after the treatment revealed a notable reduction in the volume of the lesion, ranging from 57% to 100%. Moreover, the efficacy and safety of HIFU treatment remained consistent during the 12-month follow-up period. CONCLUSION: HIFU ablation appears to be an effective and safe treatment modality for UAVF. It provides a noninvasive approach with favorable clinical outcomes.

Impacts of continuous quality improvement on wound pain in the puncture site of arteriovenous fistula in haemodialysis patient.

This study analyses the effects of a continuous quality improvement nursing model on wound pain at the arteriovenous fistula (AVF) puncture site in patients undergoing haemodialysis. Forty haemodialysis patients from the First Affiliated Hospital of Chongqing Medical University, from September 2020 to December 2022, were selected as study subjects. They were randomly divided into an observation group and a control group. The control group received conventional nursing care, while the observation group was treated with a continuous quality improvement nursing model. The study compared the impact of these nursing approaches on pain intensity post-AVF puncture, wound visual analogue scale scores, self-rating anxiety scale, self-rating depression scale, quality of life scores and patient satisfaction with nursing care. In the observation group, the proportion of patients experiencing moderate to severe pain during AVF puncture was lower than that in the control group, whereas the proportion of patients with no pain or mild pain was higher (P = 0.008). After nursing, the observation group exhibited significantly lower wound visual analogue scale scores, self-rating anxiety scale scores, and self-rating depression scale scores compared to the control group (P < 0.001), with a significantly higher quality of life score (P < 0.05). The nursing satisfaction rate was 95.00% in the observation group, significantly higher than the 65.00% in the control group (P = 0.018). The continuous quality improvement nursing model significantly reduces wound pain at the AVF puncture site in haemodialysis patients, alleviates negative emotions, enhances the quality of life, and achieves high patient satisfaction. It is thus a highly recommendable approach in nursing practice.

Pull-through technique through antegrade radial artery puncture without sheath insertion in balloon-assisted radiocephalic arteriovenous fistulas maturation.

PURPOSE: The aim of this study was to investigate the effectiveness and safety of the pull-through technique through antegrade radial artery puncture without sheath insertion in balloon-assisted radiocephalic AVF maturation. METHODS: We retrospective studied a total of 62 patients with immature radiocephalic AVF, who received balloon-assisted maturation in our hospital. 15 patients received pull-through technique through radial artery without sheath insertion and 47 patients received treatment through a regular venous approach. RESULTS: The success rate of pull-through technique group and control group was 86.7% (13 out of 15), 89.1% (41 out of 46) respectively. There was no significant difference between two groups (P > 0.05). In our study, there were 2 patients in the pull-through technique group and 3 patients in the control group, which had hematoma in the vein puncture site (P = 0.59). There were also no differences in the primary patency rate between two groups at 6 months and 12 months (76.9% vs 70.7%, 38.4% vs 41.5%, respectively, P > 0.05). CONCLUSION: The pull-through technique through antegrade radial artery without sheath insertion in promoting radiocephalic AVF maturation is effective and safe.

The risk factors for arteriovenous fistula dysfunction in maintenance hemodialysis patients: A cross-sectional study.

INTRODUCTION: Arteriovenous fistula (AVF) dysfunction is a prevalent complication among maintenance hemodialysis patients. However, the factors influencing AVF patency remain unclear. To address this, we conducted a study aimed at identifying factors contributing to AVF dysfunction in this patient population. METHODS: The study compared clinical data, vascular calcification score, and laboratory data focusing on blood cell composition and coagulation in 100 maintenance hemodialysis patients in whom an AVF had been inserted from January through September of 2022. The patients were divided into a group in which the AVF functioned without issues and a group in which the AVF was dysfunctional, defined as not able to provide a blood flow of greater than 200 mL/min. FINDINGS: Patients in the 2 groups (56 in the dysfunctional AVF group and 44 in the group with satisfactory AVF function) were similar demographically. Compared with the normally functioning AVF group, the AVF dysfunction group exhibited significantly higher Agatston calcium scores (20.5 [1.28, 298] median [Q1, Q3] vs. 1.14 [0.00, 11.6]; p = 0.01), elevated triglyceride levels (1.1 [0.6, 1.2] mmol/L vs. 0.5 [0.3, 0.8]; p < 0.01), increased prothrombin activity (113 ± 22.1% vs. 99.4 ± 23.1; p < 0.01), lower prothrombin time (10.4 [9.8, 10.8] s vs. 11.0 [10.3, 11.5]; p < 0.01), higher red blood cell (RBC) counts (3.5 ± 0.7 · 1012/L vs. 3.0 ± 0.7; p < 0.01), and elevated hemoglobin levels (98.0 ± 21.8 g/L vs. 84.9 ± 24.2; p < 0.01). Higher C-reactive protein (20.2 [3.3, 20.2] mg/L vs. 17.8 [6.2, 17.8]; p = 0.01) and procalcitonin levels (0.9 [0.4, 0.9] ng/mL vs. 0.5 [0.2, 0.7]; p < 0.01) were also noted. Logistic regression analysis indicated that platelet/lymphocyte ratio, monocyte/lymphocyte ratio, and RBC count were factors associated with AVF dysfunction. Increased monocyte/lymphocyte ratio and RBC count correlated with higher risk, while a higher platelet/lymphocyte ratio was associated with lower risk. DISCUSSION: Arteriovenous fistula dysfunction in maintenance hemodialysis patients is associated with higher proportions of specific hematological parameters, particularly elevated RBC count, and altered platelet/lymphocyte and monocyte/lymphocyte ratios.