The Significance of Inflow Artery and Tourniquet Derived Cephalic Vein Diameters on Predicting Successful Use and Patency of Arteriovenous Fistulas for Haemodialysis.

OBJECTIVE: To investigate the significance of inflow artery and cephalic vein diameters on predicting patency of radiocephalic and brachiocephalic arteriovenous fistulas (AVFs). DESIGN: Single centre study with retrospective analysis of prospectively collected data between November 2010 and July 2015. METHODS: A detailed history and physical examination was undertaken, including age, gender, history and duration of haemodialysis, cause of chronic kidney disease, and the presence of comorbidities/risk factors. Pre-operative arterial and venous upper extremity mapping was performed and inner vessel diameter was recorded, using a tourniquet for the veins. Outcome measures included AVF use (functionality), primary, primary assisted, secondary, and functional secondary patency. RESULTS: One hundred and thirty five AVFs (57 and 78 radiocephalic and brachiocephalic AVFs, respectively) were constructed and followed up for 5 years. A cephalic vein diameter <4.3 mm (lower three quartiles) was the single independent predictor of inferior secondary and also functional secondary patency of radiocephalic AVFs (p = .02, HR 11.2, 95% CI 1.44-90.9). A brachial artery diameter ≤4.1 mm (lowest quartile) was an independent predictor of AVF functionality (57% vs. 83% for larger arteries, p = .017), and inferior primary, primary assisted, secondary, and functional secondary patency of brachiocephalic AVFs (primary assisted patency 21.9% vs. 55.9% at 3 years, p = .001/log-rank test, HR 3.1, p = .002/Cox regression). The presence of lower extremity PAD or use of dual antithrombotics was also independently associated with an inferior secondary patency. The number of risk factors (brachial artery diameter ≤4.1 mm, PAD, and use of dual antithrombotics) demonstrated risk stratification capabilities for functional secondary patency. CONCLUSIONS: Among patients undergoing radiocephalic AVFs, a tourniquet derived cephalic vein diameter <4.3 mm was the single independent predictor of inferior secondary and functional secondary patency. Among patients undergoing brachiocephalic AVFs, all patency rates were inferior in the presence of a brachial artery diameter ≤4.1 mm and secondary patency was inferior in the presence of multiple risk factors.

Editor's Choice - Management of Secondary Aorto-enteric and Other Abdominal Arterio-enteric Fistulas: A Review and Pooled Data Analysis.

OBJECTIVES: To compare management strategies for secondary abdominal arterio-enteric fistulas (AEFs). METHODS: This study is a review and pooled data analysis. Medline and Scopus databases were searched for studies published between 1999 and 2015. Particular emphasis was given to short- and long-term outcomes in relation to AEF repair type. RESULTS: Two hundred and sixteen publications were retrieved, reporting on 823 patients. In-hospital mortality was 30.7%. Open surgery had higher in-hospital mortality (246/725, 33.9%), than endovascular methods (7/98, 7.1%, p < .001, OR 6.7, 95% CI 3-14.7, including staged endovascular to open surgery, 0/13, 0%). In-hospital mortality after graft removal/extra-anatomical bypass grafting was 31.2% (66/226), graft removal/in situ repair 34% (137/403), primary closure of the arterial defect 62.5% (10/16), and for miscellaneous open procedures 41.3% (33/80), p = .019. Among the subgroups of in situ repair, homografts were associated with a higher mortality than impregnated prosthetic grafts (p = .047). There was no difference in recurrent AEF-free rates between open and endovascular procedures. Extra-anatomical bypass/graft removal and in situ repair had a lower AEF recurrence rate than primary closure and homografts. Late sepsis occurred more often after endovascular surgery (2-year rates 42% vs. 19% for open, p = .001). The early survival benefit of endovascular surgery was blunted during follow-up, although it remained significant (p < .001). Within the in situ repair group, impregnated prosthetic grafts were associated with the worst overall and AEF related mortality free rates and vein grafts with the best. No recurrence, sepsis, or mortality was reported following staged endograft placement to open repair after a mean follow-up of 16.8 months (p = .18, p = .22, and p = .006, respectively, compared with patients in other groups). CONCLUSIONS: Endovascular surgery, where appropriate, is associated with better early survival than open surgery for secondary AEFs. Most of this benefit is lost during long-term follow-up, implying that a staged approach with early conversion to in situ vein grafting may achieve the best results in selected patients.

Editor's Choice - efficacy and safety of the new oral anticoagulants dabigatran, rivaroxaban, apixaban, and edoxaban in the treatment and secondary prevention of venous thromboembolism: a systematic review and meta-analysis of phase III trials.

OBJECTIVES: The aim was to perform a review of the efficacy and safety of new oral anticoagulants (NOAs) in the management of venous thromboembolism (VTE). METHODS: This was a systematic review and meta-analysis. On March 26, 2014, Medline, Embase, and the Cochrane trial register were searched for randomized controlled trials (RCTs) comparing the NOAs dabigatran, rivaroxaban, apixaban, and edoxaban with vitamin K antagonists (VKAs) in VTE treatment and secondary prevention. Two investigators assessed the methodological quality of the RCTs. The main study outcomes (efficacy, safety and net clinical benefit) were expressed as risk ratios (RR) with 95% confidence interval (CI). RESULTS: Ten RCTs, mostly with low risk of bias, with nearly 38,000 patients, were identified. In six trials of treatment, NOAs were equally effective as VKAs in preventing recurrent symptomatic VTE (RR 0.89, 95% CI 0.75-1.05), but major bleeding occurred less often (1.08% vs. 1.73% for VKAs, RR 0.63, 95% CI 0.51-0.77), leading net clinical benefit to favor NOAs (RR 0.79, 95% CI 0.70-0.90). Fatal bleeding occurred less often with NOAs (0.09% vs. 0.18% for VKAs), a difference that approached statistical significance (RR 0.51, 95% CI 0.26-1.01). In three secondary prevention trials, NOAs reduced VTE recurrence rates to 1.32% (vs. 7.24% with placebo, RR 0.17, 95% CI 0.12-0.24) and fatal pulmonary embolism (PE) (including unexplained deaths) to 0.1% (vs. 0.29% for placebo, RR 0.37, 95% CI 0.10-1.38) at the expense of clinically relevant non-major bleeding (4.3% vs. 1.8% for placebo, RR 2.32, 95% CI 1.65-3.35), but not major bleeding. All-cause mortality rate was reduced to 0.41% with NOAs (vs. 0.86% with placebo, RR 0.38, 95% CI 0.18-0.79). Net clinical benefit favored NOAs (RR 0.21, 95% CI 0.15-0.29), and NNT was 18. CONCLUSIONS: Compared to VKAs, NOAs are not only effective in treating VTE but also safer in terms of bleeding, thereby conferring clinical benefit. Their safety and efficacy was confirmed further in secondary prevention trials.

Aorto-iliac aneurysm infected by Brucella: distinctive presentation patterns of a rare entity.

There is currently a lack of information on presentation patterns and the appropriate investigation and treatment of aortic brucellosis. Herein a case affecting the iliac component of an aorto-iliac aneurysm, managed successfully with in situ graft repair, is reported. A review of the literature identified 25 cases, with the infrarenal abdominal aorta (65%) followed by the ascending thoracic aorta (23%) being mostly affected; only our case involved the iliacs. Aortic brucellosis affected mostly older men, caused pain more often than fever (in 73% and 57%, respectively), and involved frequently the spine or the aortic valve (n = 14, 56%). Preoperative diagnosis was made more often in the presence of fever (67% versus 18% in afebrile patients, P = 0.021). In situ aneurysm repair in the form of open (54%) or endovascular (8%) grafting was mostly performed. Mortality was 12% and graft infection was 13% at two years. In conclusion, aortic brucellosis has unique presentation patterns, usually affecting an abnormal or aneurysmal aorta and/or due to a contiguous spinal or aortic valve infection. Acute symptomatology with pain and/or fever occurs very often and should raise suspicion for aortic infection. Despite the seriousness of aortic involvement, mortality and reinfection rates are within acceptable levels.

Open or endovascular repair of aortoenteric fistulas? A multicentre comparative study.

OBJECTIVES: To compare aortoenteric fistula (AEF) outcome after endovascular (EV-AEFR) or open repair (O-AEFR). DESIGN: Multicentre retrospective comparative study. MATERIALS/METHODS: 25 patients with AEF (24 secondary, 23 males, median age 75 years) after aortic surgery (median four years). Preoperative sepsis was evident in 19 cases. Eight patients were managed with EV-AEFR and 17 with O-AEFR. RESULTS: The two groups were comparable in preoperative characteristics. In-hospital mortality after EV-AEFR was lower compared to O-AEFR (0% and 35%, respectively, p = 0.13). Similarly, morbidity after EV-AEFR was lower compared to O-AEFR (25% and 77%, respectively, p = 0.028). There was a trend for worse recurrence-free, sepsis-free, re-operation-free and AEF-related death-free rates after EV-AEFR, while the early survival advantage of EV-AEFR was lost after two years and the overall long-term survival rates (perioperative mortality included) of the two groups were similar. Preoperative sepsis had no effect on recurrence and sepsis-free rates (p = 0.94 and p = 0.92, respectively), but it was associated with worse two year overall survival (24% vs 50%, p = 0.32). On multivariate analysis, the number of symptoms (two vs one) at presentation was the single predictor of worse re-operation rates, AEF-related and overall survival. CONCLUSIONS: EV-AEFR was associated with no postoperative mortality in this study and can achieve satisfactory short and long-term results, comparable to O-AEFR. Further trials should focus on the role of EV-AEFR in patients at high risk for O-AEFR, due to shock or co-morbidities, or as a bridging procedure.

Patterns and outcomes of aortofemoral bypass grafting in the era of endovascular interventions.

OBJECTIVES: The aim of the study is to study contemporary presentation patterns and clinical results in patients undergoing aortofemoral bypass (AFB) surgery. DESIGN: This was a retrospective comparative study. MATERIAL AND METHODS: During a 14-year period, 269 consecutive patients (mean age 65 years) underwent AFB. Indications included occlusive disease with severe intermittent claudication (IC) (n = 86), critical limb ischaemia (CLI, n = 97) and aneurysmo-occlusive disease (n = 86). RESULTS: From 2000-07 on, AFB was performed more frequently for occlusive disease with CLI than for other indications (48% vs. 31% before 2000, P = 0.009) and also in women (51% vs. 32% before 2000, P = 0.003), compared to the period before 2000. Thirty-day mortality was reduced during 2000-2007 to 2.4%, compared with 4.3% during 1993-1999, although this difference was not statistically significant (P = 0.73). Morbidity did not change substantially over the study period. Predictors of 30-day mortality included indication (CLI = 4.1% vs. claudication = 1.2% (P = 0.37)) and chronic kidney disease (CKD, serum creatinine > 1.5 mg dl⁻¹) (11.1% vs. 2.9% in normal renal function, P = 0.07), the latter being the single predictor on multivariate analysis (hazard risk 4.2, P = 0.047). Overall 5 and 10-year assisted primary and secondary patency was 95% and 88%, and 99% and 95%, respectively. Survival at 5 and 10 years was 69% and 48%, respectively. Patient age (hazard risk 1.05, P < 0.001), CKD (hazard risk 1.79, P = 0.018) and diabetes (hazard risk 1.56, P = 0.022) were independent predictors of worse long-term survival. Long-term outcome did not change over the course of the study. CONCLUSIONS: In the contemporary era, AFB is more likely to be performed for CLI and in women than in the past. Despite these changes, perioperative mortality and morbidity remain low and long-term outcome excellent.

Basilic vein transposition: what is the optimal technique?

OBJECTIVES: To compare the outcome of the one-stage basilic vein transposition (BVT) fistula with a modified, two-stage technique. DESIGN: Retrospective case-controlled study, performed in an academic centre. MATERIAL: A total of 173 candidates for BVT fistula (87 males, mean age 61 years). METHODS: In one-stage BVT, the basilic vein is mobilised through a single incision, placed inside an anterolateral arm tunnel and anastomosed with the brachial artery. In two-stage procedures, the fistula-arterial anastomosis is created first, followed by the second stage, after fistula maturation several weeks later, when the basilic vein is mobilised through two skip incisions, transected near the anastomosis, placed inside an anterolateral arm tunnel and reanastomosed. Morbidity and fistula maturation rate were the main outcome measures. RESULTS: In one-stage BVT (n=76), the incidence of venous hypertension, wound haematomas and all complications (17%, 13% and 43%, respectively) was significantly higher than in two-stage procedures (n=98) (4%, p=0.004, 3%, p=0.012 and 11%, p<0.001, respectively). Time (68 days) to fistula use was significantly decreased in one-stage BVT than in two-stage procedures (132 days, p<0.001) but failure to mature rate was equivalent (15% vs. 18%, p=0.49). CONCLUSIONS: Our results indicate that the two-stage BVT fistula through two skip-arm incisions is superior to the established one-stage procedure in terms of less morbidity but at the cost of a second operation and longer time to access use. Further research comparing these two techniques is necessary. Until this issue is resolved, an individualised approach is suggested.

Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous thrombo-embolism in high-risk patients.

BACKGROUND: It has been suggested that combined modalities (methods of treatment) are more effective than single modalities in preventing venous thrombo-embolism (defined as deep vein thrombosis and pulmonary embolism, or both) in high-risk patients. OBJECTIVES: To assess the efficacy of intermittent pneumatic leg compression combined with pharmacological prophylaxis versus single modalities in preventing venous thrombo-embolism in high-risk patients. SEARCH STRATEGY: The Cochrane Peripheral Vascular Diseases (PVD) Group searched the reference lists of their Specialised Register (last searched 17 July 2007) and the Cochrane Central Register of Controlled Trials (CENTRAL) (last searched The Cochrane Library 2008, issue 3) for relevant articles to identify additional trials. SELECTION CRITERIA: Randomised controlled trials (RCTs) or controlled clinical trials (CCTs) of combined intermittent pneumatic leg compression and pharmacological interventions used to prevent venous thrombo-embolism in high-risk patients. DATA COLLECTION AND ANALYSIS: Data extraction was undertaken independently by two review authors using data extraction sheets.

Secondary patency of thrombosed prosthetic vascular access grafts with aggressive surveillance, monitoring and endovascular management.

BACKGROUND: To study the long-term patency of thrombosed prosthetic vascular access grafts treated with percutaneous mechanical thrombectomy (PMT) followed by aggressive surveillance and monitoring and repeated endovascular interventions. STUDY DESIGN: Two hundred seven vascular access grafts presented with first-time thrombosis were treated with PMT using the AngioJet device (n=185) or the Arrow-Trerotola percutaneous thrombolytic device (n=22) followed by angioplasty (+/- stenting) of the anatomical lesion responsible for the thrombotic event. Clinical success was considered at least one successful subsequent hemodialysis session. Graft surveillance/monitoring included clinical and hemodialysis parameters to detect a failing or thrombosed graft. RESULTS: PMT was technically successful in 202 cases (97.6%) and clinically successful in 193 cases (93.2%). During follow-up, 149 got thrombosed and either abandoned (n=33) or underwent at least once repeat thrombectomy (n=116); finally 100 grafts were abandoned (n=90), ligated (n=5) or removed (n=5). Endovascular management (0.54 procedures per 100 graft-days, thrombectomy, n=307 sessions and angioplasty, n=162 sessions) increased significantly functional assisted-primary patency rates from 29% and 14% at 1 and 2 years to a secondary patency of 62% and 47%, respectively. Secondary patency was worse in loop grafts (P=.02) and intermediate graft thrombosis (occurred between 31-182 days after graft placement, P<.001) and better when renal failure was due to hypertension or diabetes (compared to other or cryptogenic causes, P=.048) or isolated angioplasty for graft dysfunction during follow-up had been performed (P<.001). Multivariate analysis identified intermediate graft thrombosis and isolated angioplasty as independent predictors of secondary patency (P<.001, relative risk 2.77 and P<.001, relative risk 0.28, respectively). CONCLUSIONS: PMT is a highly successful procedure with acceptable long-term secondary patency results, provided that aggressive endovascular management of subsequent thrombotic or dysfunction episode is performed. Further research to identify the causes of intermediate graft thrombosis is justified.