Risks and benefits of renal artery stenting in fibromuscular dysplasia: Lessons from the ARCADIA-POL study.

INTRODUCTION: Although renal stenting is the standard revascularization method for atherosclerotic renal artery stenosis (RAS) (FMD-RAS), stenting in fibromuscular dysplasia (FMD) RAS is usually limited to periprocedural complications of angioplasty and primary arterial dissection. The main aim of the study was to retrospectively analyze the immediate and long-term results of renal stenting versus angioplasty in patients with FMD. METHODS: Of 343 patients in the ARCADIA-POL registry, 58 patients underwent percutaneous treatment due to FMD-RAS (in 70 arteries). Percutaneous transluminal renal angioplasty (PTRA) was performed as an initial treatment in 61 arteries (PTRA-group), whereas primary stenting was undertaken in nine arteries (stent-group). Stent-related complications were defined as: in-stent restenosis > 50% (ISR); stent fracture; under-expansion; or migration. RESULTS: In the PTRA-group, the initial restenosis rate was 50.8%. A second procedure was then performed in 22 arteries: re-PTRA (12 arteries) or stenting (10 arteries). The incidence of recurrent restenosis after re-PTRA was 41.7%. Complications occurred in seven of 10 (70%) arteries secondarily treated by stenting: two with under-expansion and five with ISR. In the stent-group, stent under-expansion occurred in one case (11.1%) and ISR in three of nine stents (33.3%). In combined analysis of stented arteries, either primarily or secondarily, stent-related complications occurred in 11/19 stenting procedures (57.9%): three due to under-expansion and eight due to ISRs. Finally, despite several revascularization attempts, four of 19 (21%) stented arteries were totally occluded and one was significantly stenosed at follow-up imaging. CONCLUSION: Our study indicates that renal stenting in FMD-RAS may carry a high risk of late complications, including stent occlusion. Further observational data from large-scale registries are required.

Red blood cell distribution width is associated with increased interactions of blood cells with vascular wall.

The mechanism underlying the association between elevated red cell distribution width (RDW) and poor prognosis in variety of diseases is unknown although many researchers consider RDW a marker of inflammation. We hypothesized that RDW directly affects intravascular hemodynamics, interactions between circulating cells and vessel wall, inducing local changes predisposing to atherothrombosis. We applied different human and animal models to verify our hypothesis. Carotid plaques harvested from patients with high RDW had increased expression of genes and proteins associated with accelerated atherosclerosis as compared to subjects with low RDW. In microfluidic channels samples of blood from high RDW subjects showed flow pattern facilitating direct interaction with vessel wall. Flow pattern was also dependent on RDW value in mouse carotid arteries analyzed with Magnetic Resonance Imaging. In different mouse models of elevated RDW accelerated development of atherosclerotic lesions in aortas was observed. Therefore, comprehensive biological, fluid physics and optics studies showed that variation of red blood cells size measured by RDW results in increased interactions between vascular wall and circulating morphotic elements which contribute to vascular pathology.

MMP-9, TIMP-1 and S100B protein as markers of ischemic stroke in patients after carotid artery endarterectomy.

Ischemic stroke is the main cause of permanent disability in adult patients. No commonly accepted method were discovered to predict stroke before the first symptoms. Activation of matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMP) and S100B protein may be observe in patients with symptomatic carotid artery stenosis. Hemorrhagic transformation of ischemic stroke may be associated with changes in MMP, TIMP and S100B. AIM: The aim of this study was to determine if MMP-9, TIMP-1 and S-100B protein may markers of forthcoming ischemic stroke in patients undergoing carotid endarterectomy. MATERIALS AND METHODS: Blood samples were taken and an analysis of circulating proteins (MMP-9, TIMP-1, S100B) 73 subsequent patients with carotid artery stenosis ≥70% (33 asymptomatic and 40 symptomatic), who were referred for potential revascularization. RESULTS: A statistically significant difference was found between MMP- 9 levels in patients with ischemic stroke compared to patients with asymptomatic carotid stenosis after endarterectomy. Also, average TIMP-1 levels in patients with ischemic stroke and stenosis ≥70% were statistically significantly higher than the average levels in patients after endarterectomy. In terms of S-100B, a higher mean value was observed in patients with stroke than in endarterectomy group. No statistical differences were found in the levels of that proteins in the hemorrhagic transformation of ischemic stroke. CONCLUSIONS: Increased levels of MMP-9, TIMP-1 and S-100B in patients with ischemic stroke compared to patients with asymptomatic carotid stenosis after endarterectomy showed that abovementioned proteins may be a good predictive factor of ischemic stroke in patients undergoing carotid endarterectomy.

To Close, Observe, or Reconstruct: The Third Way of Managing Dialysis Fistula Aneurysms in Kidney Transplant Recipients.

BACKGROUND: The management of patent dialysis fistulas in patients after kidney transplantation (KTx) is controversial-the options that are usually considered are the fistula's closure or observation. Many complications of dialysis fistulas occur in patients after KTx, and immunosuppression increases the risk of fistula aneurysms and hyperkinetic flow. This study aimed to evaluate the results of dialysis fistula aneurysm treatment in patients after KTx and to compare them to procedures performed in an end-stage renal disease (ESRD) dialyzed population. METHODS: We enrolled 83 renal transplant recipients and 123 ESRD patients with dialysis fistula aneurysms qualified for surgical revision to this single-center, prospective study. The results of the surgical treatment of dialysis fistula aneurysms were analyzed, and the primary, assisted primary and secondary patency rate, percentage and type of complications were also assessed. RESULTS: For the treatment of dialysis fistula aneurysms in transplant patients, we performed dialysis fistula excisions with fistula closure in 50 patients (60.2%), excision with primary fistula reconstruction (n = 10, 12.0%) or excision with PTFE bypasses (n = 23, 27.7%). Postoperative complications occurred in 11 patients (13.3%) during a follow-up (median follow-up, 36 months), mostly in distant periods (median time after correction procedure, 11.7 months). The most common complication was outflow stenosis, followed by hematoma, dialysis fistula thrombosis and the formation of a new aneurysm and postoperative bleeding, infection and lymphocele. The 12-month primary, primary assisted and secondary patency rates of fistulas corrected by aneurysm excision and primary reconstruction in the KTx group were all 100%; in the control ESRD group, the 12-month primary rate was 70%, and the primary assisted and secondary patency rates were 100%. The 12-month primary, primarily assisted and secondary patency rates after dialysis fistula aneurysm excision combined with PTFE bypass were better in the KTx group than in the control ESRD group (85% vs. 71.8%, 90% vs. 84.5% and 95% vs. 91.7%, respectively). Kaplan-Meier analysis showed a significant difference in primary patency (p = 0.018) and assisted primary (p = 0.018) rates and a strong tendency in secondary patency rates (p = 0.053) between the KTx and ESRD groups after dialysis fistula excisions combined with PTFE bypass. No statistically significant differences in patency rates between fistulas treated by primary reconstruction and reconstructed with PTFE bypass were observed in KTx patients. CONCLUSIONS: Reconstructions of dialysis fistula aneurysms give good long-term results, with a low risk of complications. The reconstruction of dialysis fistulas can be an effective treatment method. Thus, this is an attractive option in addition to fistula ligation or observation in patients after KTx. Reconstructions of dialysis fistula aneurysms enable the preservation of the dialysis fistula while reducing various complications.

Aneurysm Excision With Arteriovenous Anastomosis Proximalization for Dialysis Fistula Aneurysm Treatment.

INTRODUCTION: Dialysis fistula aneurysms are common complications, which require surgical revision in selective cases. The results of aneurysm excision with arteriovenous anastomosis proximalization for the treatment of dialysis fistula aneurysms have been described below. METHODS: Patients qualified for the reconstruction of a dialysis fistula aneurysm underwent a duplex ultrasound examination. The diameter, length of the aneurysm, relations with the artery, thrombus presence and blood flow were determined. In the case of favorable anatomical conditions, we performed aneurysm excision with arteriovenous anastomosis proximalization as the procedure of choice. Patients, dialysis access, operative data and the results obtained during a median follow-up of 41 months were then analyzed. FINDINGS: Since 2012, we have performed 20 aneurysm excision combined with primary anastomosis as dialysis fistula aneurysm treatment. In 18 patients, aneurysm excision was combined with simple re-anastomosis in the more proximal arterial segment. In 2 autogenous radio-cephalic forearm direct fistulas the aneurysm excision was combined with switching anastomosis type from side-to-end to end-to-end. The 12- and 24-month primary patency rates of corrected fistulas in the observed group were 94.7% and 82.4%, respectively. No early complications were noted. In 7 patients (35%) we observed late complications, which required reintervention or led to access failure. Dialysis fistula thrombosis as an indication for treatment was a significant risk factor for late re-occlusion. DISCUSSION: A simple primary reconstruction by arteriovenous anastomosis proximalization and aneurysm excision for the surgical correction of dialysis fistula aneurysms has potential benefits compared to established methods-aneurysmorraphy and aneurysm excision with a vascular prosthesis bypass. The obtained data showed the efficiency, safety and excellent long-term results of this procedure.

Role of Magnetic Resonance Spectroscopy in Evaluation of Cerebral Metabolic Status Before and After Carotid Endarterectomy/Thromboendarterectomy and Carotid Artery Stenting in Patients with Asymptomatic Critical Internal Carotid Artery Stenosis.

BACKGROUND The relative efficacy of carotid endarterectomy (CEA)/thromboendarterectomy (TEA) and carotid artery stenting (CAS) already has been compared in randomized controlled trials and a meta-analysis, but only limited data exist describing the status of cerebral metabolism before and after these interventions. The aim of the present study was to compare metabolic changes before and after treatment of carotid stenosis and assess their potential clinical implications.   MATERIAL AND METHODS Patients with asymptomatic unilateral critical internal CAS were imaged with proton 3T magnetic resonance spectroscopy (H-MRS) because the technique is more sensitive than regular magnetic resonance imaging for detection of the early signs of ischemic events. Abnormal metabolite ratios detected with H-MRS may precede actual morphological changes associated with hypoperfusion as well as reperfusion changes. Ipsilateral and contralateral middle cerebral artery vascular territories were both evaluated before and after vascular intervention. H-MRS was performed within 24 h before and after surgery. Correlations in the metabolic data from H-MRS for N-acetylaspartic acid (NAA)+N-acetylaspartylglutamate, creatinine (Cr)+phosphocreatinine, and phosphocholine+glycerophosphocholine (Cho) were sought. RESULTS H-MRS voxels from 11 subjects were analyzed. Values for dCho/CrI, dCho/CrC and Cho/Naal (P<0.001) were significantly higher ipsilaterally than contralaterally. Ratios for dNaa/ChoC and Cho/NaaC were significantly higher on the non-operated side (P<0.001). CONCLUSIONS H-MRS may be helpful for assessment of patients with CAS, particularly because unlike other modalities, it reveals postoperative changes in metabolic brain status. Initial results indicate the important role of perioperative neuroprotective treatment.

Hybrid procedures in the dialysis fistula aneurysm treatment.

OBJECTIVES: Dialysis fistula aneurysms are common complications which in selective cases require surgical revision. It is recommended to detect and treat outflow stenosis concurrent with a dialysis fistula aneurysm, but usually, the treatment is divided into two stages - the open and endovascular stages are performed separately. We describe the results of hybrid procedures composed of aneurysm resection and endovascular correction for outflow veins performed for a dialysis fistula aneurysm treatment. METHODS: From March 2012, we performed hybrid procedures in 28 patients to correct dialysis fistula aneurysms. Patients, dialysis access, operative data, and the results obtained during a median follow-up of 28.5 months were analyzed. RESULTS: For dialysis fistula aneurysm correction, we performed 27 bypasses and 1 aneurysmorraphy. For outflow vein stenosis correction, we performed standard balloon angioplasty, no stents or stentgraft were used. The average increase in minimal diameter after angioplasty was 135.5% (range 57-275%). The 12- and 24-month primary patency rates of corrected fistulas in the observed group were 92.3% and 80%, respectively. A significant difference in the one-year patency rates between the urgent and planned procedures was observed (81.2% vs. 100%, respectively). No early complications related to endovascular or open procedures were observed. Late complications were observed in seven patients (25%) - mainly thrombosis caused by the recurrence of outflow vein stenosis (six patients, 21.5%), infection, lymphocele, and hematoma (one case of each complication). CONCLUSIONS: A hybrid procedure for the surgical correction of dialysis fistula aneurysms with the simultaneous correction of outflow pathologies enables effective long-term treatment. The obtained data showed the efficiency and good results of this procedure. Procedures performed for urgent indications significantly increase the risk for later complications, especially fistula thrombosis and loss of dialysis access.

Red-cell distribution width is associated with higher risk of vascular complications after carotid thromboendartherectomy.

Red Cell Distribution Width (RDW) is associated with increased morbidity and mortality in subjects with clinically manifested vascular diseases as well as predicts cardiovascular incidents and different types of cancer in a healthy population. AIM: The aim of the study was to evaluate relationship between clinical outcomes in patients after carotid thromboendarterectomy and initial RDW values. MATERIALS AND METHODS: Data from 115 subsequent patients who underwent carotid thromboendartherectomy (TEA) were retrospectively analyzed. All patients had complete blood count measured including RDW and were observed for 18 months post-operatively. On each visit doppler ultrasound of carotid arteries was performed to evaluate the development of restenosis and progression of atherosclerosis. RESULTS: Primary endpoint defined as cardiovascular death, new cerebrovascular incidents (stroke or TIA), any new revascularization procedure (carotid, coronary or peripheral) and restenosis of the operated artery occurred in 28 patients. They differed from subjects with uneventful course with increased prevalence of previous cerebrovascular incidents (75.0% and 42.5%, respectively; p=0.0028) and higher RDW values (14,37±1.55% and 13.77±0.96%, p=0.0155). CONCLUSIONS: In patients with high risk for cerebrovascular incidents, RDW identifies population at increasingly high probability of vascular complications which should be subjected to intensive therapeutic regimen.

Creation of Arteriovenous Fistulas and Grafts Concomitantly with Endovascular Correction of Outflow Veins: A Hybrid Procedure.

BACKGROUND: Achieving well-functioning dialysis fistulas is a common problem in dialyzed patients, and it is mainly caused by the pathologies of vessels used for fistula creation. Hybrid therapies, combining surgical and endovascular procedures, potentially enable the creation of functional dialysis fistulas in patients with vessels that are otherwise unsuitable for vascular access. METHODS: Between January 1, 2014 and June 30, 2018, we created dialysis fistulas simultaneously with endovascular correction of outflow pathologies in 15 patients. The included patients had a long history of dialysis (median 10.5 years, range 3-22) and many previous dialysis access procedures (mean 5.3 procedures, range 2-9). In 13 patients (86.7%), the fistula was created on the upper arm; in 5 patients (33.3%), it was arteriovenous graft done with polytetrafluoroethylene (PTFE) prosthesis (in an additional 3 patients, a PTFE prosthesis was used to extend the vein), and 7 patients had native vessel fistulas (46.7%). Endovascular procedures, in some cases performed on more than 1 vein, were applied for correction of the subclavian vein (8 patients, 53.3%); brachiocephalic vein (6 patients, 40.0%); cephalic, basilic, and axillary veins (2 patients each, 13.3%); and superior cava vein (1 patient, 6.7%). Access for the endovascular procedure was achieved through a dissected vein used for arteriovenous anastomosis. The fistula function was monitored, and all complications of dialysis access were noted. The median follow-up in the observed group was 18 months. We compared the patency of dialysis fistula creation combined with endovascular correction of outflow vein pathology to our results of standard dialysis fistula operations: radiocephalic dialysis fistula creation (RCAVF group, 65 patients) and dialysis fistula stenosis angioplasty (PTA group, 30 patients). RESULTS: The 12- and 24-month primary patency rates of dialysis fistulas created in hybrid procedures with simultaneous outflow vein pathology correction were 72.7% and 63.6%, respectively. No early complications related to endovascular or open procedures were observed. CONCLUSIONS: A hybrid procedure for the creation of a dialysis fistula with the simultaneous correction of outflow pathologies enables a properly functioning dialysis fistula to be obtained. This procedure can be performed in patients with complicated vascular situations, enabling the creation of dialysis fistulas. Our results of hybrid procedures, involving simultaneous endovascular correction of the outflow vein with dialysis fistula creation, showed the efficiency and good results.

False Aneurysms Complicating Internal Carotid Artery Dissection.

Pseudoaneurysm formation is a rare but dangerous complication of carotid artery dissection. It can result from trauma, spontaneous artery dissection, or iatrogenic causes. Presence of symptoms and ineffective medical therapy are one of the indications for invasive treatment. We present the case of 3 symptomatic patients with dissecting pseudoaneurysms-2 traumatic and 1 spontaneous. They were treated with 3 different endovascular procedures: the use of covered stentgraft, trans-stent coil embolization, and carotid stenting. After invasive and dual antiplatelet therapy, complete resolution of symptoms was achieved in all patients.

Ultrasound-guided angioplasty of dialysis fistulas in renal transplant patients.

INTRODUCTION: Percutaneous endovascular angioplasty has become the treatment of choice for dialysis fistula stenosis. The ultrasound-guided endovascular procedure is used in patients with severe renal impairment and advanced renal transplant failure, when the need for nephrotoxic contrast administration in standard angioplasty may worsen renal function. AIM: To evaluate endovascular angioplasty guided by ultrasound for dialysis fistula stenosis in renal transplant patients with severe graft insufficiency. MATERIAL AND METHODS: We compared ultrasound (US)-guided angioplasty, performed in patients after renal transplantation, with standard contrast angioplasty performed in dialysis patients. We treated 10 kidney allograft recipients (9 kidneys and 1 kidney-pancreas) with significantly compromised renal transplant function and significant stenosis in dialysis fistulas, as detected during US examination. Patients were qualified for percutaneous angioplasty under US guidance. The mean period from transplantation was 32.7 months (5-100 months). Results of their treatment were compared to the control group of 20 end-stage renal disease patients with dialysis fistula stenosis treated by angioplasty under standard contrast visualization. RESULTS: The immediate effectiveness of the angioplasty was 100% in both groups. No early complications of angioplasty or problems with the guidewire crossing the stenosis were observed. Twelve months of primary patency was observed in 80% and 45% in the US-guided and control groups, respectively. CONCLUSIONS: The US-guided endovascular procedure is an effective and safe method of treating dialysis fistula stenosis in patients with impaired renal transplant function.

Critical Hand Ischemia After Radial Access for Coronary Angiography - Case Report.

BACKGROUND: Radial artery is now the most frequent access for coronary angiography and intervention. Despite the common opinion that it is safer than femoral access, it has the potential for serious complications. One of them is upper limb ischemia caused by radial artery thrombosis. CASE REPORT: We are presenting a case of critical hand ischemia after coronary angiography performed through radial access despite existing risk factors, which may be considered as relative contraindications. CONCLUSIONS: In the presented case, decision was made to use radial access despite several risk factors of upper limb ischemia - diabetes, end-stage renal failure, hyperparathyroidism, or even symptoms of left upper limb ischemia. Furthermore, for diagnostic coronary angiography 5F instead of 4F introducer was used.

Genetic Polymorphism and Messenger Ribonucleic Acid Concentrations of TNFα and TGFß Genes in Patients with Chronic Lower Limb Infections.

BACKGROUND: The number of chronic lower limb infections and their complications as venous and diabetic ulcers and chronic calf dermatitis is increasing worldwide. The clinical course and outcome in the immune responses to infection have been shown to be associated with genetic polymorphisms. The aim of study was to investigate frequencies of chosen single nucleotide polymorphisms (SNPs) in TNFα and TGFß genes in patients with chronic lower limb infections and evaluate expression of messenger ribonucleic acid (mRNA) concentrations in chronic leg ulcers. METHODS: Patients were divided into three groups: (group A) chronic venous leg ulcers, (group B) chronic post-traumatic non-healing wounds, and (group C) infected ischemic necrosis of the foot. Blood donors comprised the control group. Detection of polymorphisms was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and gene expression by real-time PCR methods. RESULTS: Patients in all groups showed higher frequency of TNFα gene polymorphism -308GG and lower frequency of -308GA genotypes than controls. The mutated homozygote AA was higher in groups A and B than in controls. The TGFß74GG genotype was represented at highest values in group B. The GC genotype was found in all groups at a similar concentration lower than in controls. Genotypes TGFß29TT and TC were represented at similar concentrations as controls. Analyses showed that the presence of the polymorphic allele -308A of TNFα gene was correlated with an increased concentration of gene expression in patients with chronic leg ulcers (group A). In the case of both TGFß gene polymorphisms the presence of polymorphic allele C resulted in increased TGFß gene expression. CONCLUSIONS: Comparison of genotypes in polymorphic sites in TNFα and TGFß genes with their expression concentrations showed that the presence of polymorphic alleles could predispose to increased production of their proteins. Patients with prolonged non-healing wounds should have their genotypes studied, and in cases of mutation, long-term antibiotic and immune protein supply should be considered.

Cryptic Bacteria of Lower Limb Deep Tissues as a Possible Cause of Inflammatory and Necrotic Changes in Ischemia, Venous Stasis and Varices, and Lymphedema.

BACKGROUND: Infections and inflammation of the lower limb skin, soft tissues, and vessels are more common than in other body regions. The aim was to determine whether cryptic bacteria dwelling in deep tissues are the cause. METHODS: We performed bacteriologic studies of specimens harvested from arteries of amputated ischemic legs, leg varices, and tissue fluid/lymph and lymphatics in lymphedema. RESULTS: Calf arteries contained isolates in 61% and femoral arteries in 36%, whereas normal cadaveric organ donors' arteries in 11%. Bacterial deoxyribonucleic acid (DNA) was detected in 70%. The majority of isolates belonged to the coagulase-negative staphylococci and Staphylococcus aureus; however, highly pathogenic bacteria were also detected. All were sensitive to all antibiotics except penicillin. Saphenous vein varices contained bacterial cells in 40% and controls 4%; bacterial DNA was found in 69%. The majority of bacteria were S. epidermidis and S. aureus susceptible to all antibiotics except penicillin, Lymph and epifascial lymphatics limb contained bacteria in 60% and 33% samples, respectively and controls in 7%. Most were S. epidermidis susceptible to all antibiotics except penicillin. CONCLUSION: Cryptic bacteria are present in lower limb tissues and may play a pathologic role in surgical site infections. Proper antibacterial prophylaxis should be considered when planning surgical interventions.

Upper limb ischaemia after formation of dialysis fistula.

UNLABELLED: Limb ischaemia caused by formation of dialysis fistula is rare but serious complication. The severity of symptoms may vary but rest pains and necrotic lesions are observed in most advance cases. In these patients different invasive procedures for treatment are performed - from simplest dialysis fistula ligation to complicated vascular reconstructions. The aim of the study was to evaluate treatment results of upper limb ischaemia triggered by dialysis fistula. MATERIAL AND METHODS: We have analysed methods and results of treatment of 14 patients with symptomatic upper limb ischaemia caused by dialysis fistula treated in our department between 1st January, 2006 and 30th June, 2013. Treatment was subject to anatomical situation and clinical symptoms. In three patients the ligation of dialysis fistula was performed, four patients underwent inflow reconstruction - in one case by ligation of ligation of vein branch, in three patients by cephalic transfer of arterial anastomosis. In 2 patients hyperkinetic fistula aneurysm was excised and replaced by PTFE bypass, in three patients fistula reconstruction with DRIL method (distal revascularization - interval ligation) was performed, in one patient surgical operation of brachial artery stenosis was conducted. One patient underwent brachial artery angioplasty. RESULTS: Rest pains occurred in all patients (100%), regressive changes in 10 patients (71.4%). Eight patients (57.2%) had concomitant diabetes, seven (50%) ischaemic heart disease, five (35.5%) chronic lower limb ischemia and hyperparathyroidism was observed in fivepatients (35.5%). The imaging studies in all patients revealed pathological steal syndrome (stealing blood to the fistula), in majority concurrent with other pathologies - obstruction stenosis of peripheral artery, defects in blood out flow from the limb. As a result of the surgical treatment, symptoms of limb ischaemia subsided in all patients. CONCLUSIONS: Critical limb ischaemia caused by dialysis fistula is a dangerous complication. In most cases there are several causes of ischaemia. Treatment methods should be selected individually for each patient and clinical situation. Clinical symptoms should subside as a result of optimal choice of treatment and, if possible, maintaining of dialysis access.

Ultrasound-guided angioplasty of dialysis fistula - technique description.

Endovascular procedures are commonly used for treatment of vascular pathologies. These interventions are routinely performed under angiographic control. Angioplasty is increasingly more often used for correction of dialysis fistula - especially dilatation of stenosis. We describe the technique of dialysis fistula angioplasty under ultrasound control. Benefits of this procedure include lack of nephrotoxic contrast, what is especially important in chronic kidney disease patients in pre-dialysis period. Advantages of ultrasound guidance during dialysis fistula angioplasty lead to cause more and more frequent employment of this technique.

A high red blood cell distribution width predicts failure of arteriovenous fistula.

In hemodialysis patients, a native arteriovenous fistula (AVF) is the preferred form of permanent vascular access. Despite recent improvements, vascular access dysfunction remains an important cause of morbidity in these patients. In this prospective observational cohort study, we evaluated potential risk factors for native AVF dysfunction. We included 68 patients with chronic renal disease stage 5 eligible for AVF construction at the Department of General and Vascular Surgery, Central Clinical Hospital Ministry of Internal Affairs, Warsaw, Poland. Patient characteristics and biochemical parameters associated with increased risk for AVF failure were identified using Cox proportional hazards models. Vessel biopsies were analyzed for inflammatory cells and potential associations with biochemical parameters. In multivariable analysis, independent predictors of AVF dysfunction were the number of white blood cells (hazard ratio [HR] 1.67; 95% confidence interval [CI] 1.24 to 2.25; p<0.001), monocyte number (HR 0.02; 95% CI 0.00 to 0.21; p = 0.001), and red blood cell distribution width (RDW) (HR 1.44; 95% CI 1.17 to 1.78; p<0.001). RDW was the only significant factor in receiver operating characteristic curve analysis (area under the curve 0.644; CI 0.51 to 0.76; p = 0.046). RDW>16.2% was associated with a significantly reduced AVF patency frequency 24 months after surgery. Immunohistochemical analysis revealed CD45-positive cells in the artery/vein of 39% of patients and CD68-positive cells in 37%. Patients with CD68-positive cells in the vessels had significantly higher white blood cell count. We conclude that RDW, a readily available laboratory value, is a novel prognostic marker for AVF failure. Further studies are warranted to establish the mechanistic link between high RDW and AVF failure.

Preoperative ultrasonographic examination of the radial artery and the cephalic vein and risks of dialysis arterio-venous fistula dysfunction.

BACKGROUND: Hemodialysis used as renal replacement therapy requires a well-functioning vascular access. Arterio-venous fistula (AVF) created on the forearm is the best vascular access, but it also reveals numerous complications such as: lack of fistula maturation and hemodynamically significant stenoses. Many risk factors of fistula dysfunction are still not identified. MATERIAL/METHODS: Radial artery and cephalic vein diameter and patency were ultrasonographically examined before forearm AVF creation. Intima-media complex width, blood flow and peak systolic velocity in distal part of radial artery were measured. Presence of thrombosis and post-inflammatory changes in cephalic vein were also checked. Forearm AVF was created in 66 patients. Fistula US examination was performed 3 and 12 months after operation with measurement of vessel diameter and blood flow. Fistula patency was observed in 24 months after creation. Comparison of pre- and postoperative US examinations between groups with well functioning and thrombosed fistulas was performed. RESULTS: Primary patency of forearm AVF after 12 and 24 months was 65.2% and 53.0%, respectively. Patients with well functioning forearm AVF have significantly bigger cephalic vein diameter and peak systolic velocity in radial artery. We did not observe significant influence of radial artery intima-media complex width and radial artery diameter on AVF function. In postoperative examination, fistula diameter and flow significantly influenced the risk of AVF thrombosis. CONCLUSIONS: US examination of radial artery and cephalic vein performed before forearm AVF creation enables identification of patients with greater risk of fistula dysfunction. Cephalic vein diameter and peak systolic velocity are prognostic factors of fistula function. Control postoperative US examination of forearm fistula enables detection of AVF at risk of thrombosis.