USE of IMplanting the Biotronik PassEo-18 Lux drug coated balloon to treat failing haemodialysis arteRiovenous FIstulas and grafts (SEMPER FI Study).

BACKGROUND: Plain old balloon angioplasty has been the mainstay of treatment for arteriovenous fistula (AVF) stenoses. Recent studies suggest that drug coated balloons (DCB) may significantly reduce re-intervention rates on native and recurrent lesions. The Passeo-18 Lux DCB (Biotronik AG, Buelach, Switzerland) is packaged with a 3.0 µg/mm2 dose of paclitaxel. The hypothesis is that its use provides better target lesion primary patency (TLPP), primary assisted patency (PP), secondary patency (SP) rates and reduces the number of visits for re-intervention in a cohort of patients with stenotic AVF and arteriovenous grafts (AVGs). METHODS: The USE of IMplanting the Biotronik PassEo-18 Lux DCB to treat failing haemodialysis arteRiovenous FIstulas and grafts trial (SEMPER FI) was a prospective double-centre, multi-investigator, non-consecutive, non-blinded single-arm study investigating the efficacy and safety of the Passeo-18 Lux DCB in patients with stenotic AVF/AVG lesions between January 2021 and January 2022. Patient demographics, clinical characteristics, vascular access history, operative indications, details and outcomes were collected prospectively. TLPP, circuit access primary patency (CAP), PP, SP and deaths 6- and 12-months post-intervention were studied. RESULTS: Ninety-one patients with 110 lesions were recruited across the two centres. 62.6% (n = 57) were male with a median age of 63.5 years (SD = 10.5). 62.6% (n = 57) were taking anti-platelets. Eighty-five AVFs and six AVGs were treated. 60% (n = 54) of AVFs intervened were radiocephalic. 52.7% (n = 58) of targeted lesions were juxta-anastomotic stenosis (JAS) and one-third (n = 33) at the AVF/AVG outflow. 70.9% (n = 78) of lesions were recurrent. Median time from last intervention was 219 days. 78% of target lesions (n = 85) and circuits (n = 70) were patent at 6-months, of which 96.7% (n = 87) of those requiring assisted intervention were patent. CONCLUSION: This study shows that the Passeo-18 Lux DCB can be an effective and safe tool in the treatment of failing haemodialysis AVFs/AVGs.

Intervention with selution SLR™ Agent Balloon for Endovascular Latent Limus therapy for failing AV Fistulas (ISABELLA) Trial: Protocol for a pilot clinical study and pre-clinical results.

BACKGROUND: The aim of this pilot clinical study is to evaluate the safety and efficacy of the Selution Sustained Limus Release (SLR)™ sirolimus-coated balloon (M.A. MedAlliance SA, Nyon, Switzerland) for improving the patency of failing arterio-venous fistulas (AVF) in hemodialysis patients. We also present herein a pre-clinical pharmacokinetic and safety evaluation of Selution™ to justify its first use in hemodialysis patients for endovascular access salvage. METHODS AND RESULTS: This is an investigator-initiated prospective single-center, non-blinded single-arm trial. Forty patients with clinically significant de novo or recurrent stenoses in a mature AVF circuit will be recruited. All stenotic lesions will be prepared with high pressure non-compliant conventional balloon angioplasty (CBA) prior to deployment of the Sustained-Release Selution™ sirolimus drug-eluting balloon. The primary efficacy endpoint is 6-month target lesion primary patency and the primary safety endpoint is freedom from localized or systemic serious adverse events through 30 days. Secondary endpoints of interest include technical and clinical success rates and circuit access patency at 3 and 6 months. Follow-up will occur for 2 years for those patients whose AVFs remain patent. Pharmacokinetic and histological animal safety studies performed with the Selution™ coating formulation showed prolonged arterial tissue retention of sirolimus with therapeutic levels up to 60 days and non-toxic and rapidly declining blood levels. Histological results in animal models demonstrated safety, freedom from intraluminal thrombus, reduction in restenosis by sirolimus elution compared to CBA, and no evidence of embolic phenomena indicative of adverse particulate effects. DISCUSSION: Long release sirolimus coated balloons may serve as a promising novel alternative therapy to paclitaxel-based technology for treating conduit stenosis secondary to neointimal hyperplasia. Pre-clinical pharmacokinetic and histological animal data are encouraging and provide suggestion of safety and efficacy in this setting. This single-center trial will provide a first step toward demonstration of efficacy and safety of this device for treatment of stenotic fistulas.

Two-year clinical outcomes following lower limb endovascular revascularisation for chronic limb-threatening ischaemia at a tertiary Asian vascular centre in Singapore.

INTRODUCTION: Percutaneous transluminal angioplasty (PTA) is commonly used to treat patients with chronic limb-threatening ischaemia (CLTI). This study aimed to examine the mortality and functional outcomes of patients with CLTI who predominantly had diabetes mellitus in a multi-ethnic Asian population in Singapore. METHODS: Patients with CLTI who underwent PTA between January 2015 and March 2017 at the Vascular Unit at Singapore General Hospital, Singapore, were studied. Primary outcome measures were 30-day unplanned readmission, two-year major lower extremity amputation (LEA), mortality rates, and ambulation status at one, six and 12 months. RESULTS: A total of 221 procedures were performed on 207 patients, of whom 184 (88.9%) were diabetics. The one-, six- and 12-month mortality rate was 7.7%, 16.4% and 21.7%, respectively. The two-year LEA rate was 30.0%. At six and 12 months, only 96 (46.4%) and 93 (44.9%) patients were ambulant, respectively. Multivariate analysis revealed that preoperative ambulatory status, haemoglobin, Wound Ischaemia and foot Infection (WIfI) score, and end-stage renal failure (ESRF) were independent predictors of one-year ambulatory status. Predictors of mortality at one, six and 12 months were ESRF, preoperative albumin level, impaired functional status and employment status. CONCLUSION: PTA for CLTI was associated with low one-year mortality and two-year LEA rates but did not significantly improve ambulation status. ESRF and hypoalbuminaemia were independent predictors of mortality. ESRF/CKD and WIfI score were independent predictors of loss of ambulation at six months and one year. We need better risk stratification for patients with CLTI to decide between initial revascularisation and an immediate LEA policy.

SIroliMus coated angioPlasty versus plain balloon angioplasty in the tREatment of dialySis acceSs dysfunctION (IMPRESSION): study protocol for a randomized controlled trial.

BACKGROUND: Percutaneous transluminal angioplasty is the current standard treatment for arteriovenous fistula (AVF) stenosis. The mid- and long-term patency with plain balloon angioplasty (PBA) is however far from satisfactory. While paclitaxel-coated balloon angioplasty has been shown to be superior to PBA, concern over its safety profile has recently arisen after a reported possible increased mortality risk with a meta-analysis of large lower limb studies. An angioplasty balloon with a new type of drug coating, the sirolimus-coated balloon (SCB), has been proven to improve patency in the coronary arteries. However, its effect on AV access has yet to be studied. METHODS/DESIGN: This is an investigator-initiated, prospective, multicenter, double-blinded, randomized controlled clinical trial to assess the effectiveness of SCB compared to PBA in improving the patency of AVF after angioplasty. A total of 170 patients with mature AVF that requires PTA due to AVF dysfunction will be randomly assigned to treatment with a SCB or PBA at a 1:1 ratio, stratified by location of AVF and followed up for up to 1 year. The inclusion criteria include [1] adult patient aged 21 to 85 years who requires balloon angioplasty for dysfunctional arteriovenous fistula [2]; matured AVF, defined as being in use for at least 1 month prior to the angioplasty; and [3] successful angioplasty of the underlying stenosis with PBA, defined as less than 30% residual stenosis on digital subtraction angiography (DSA) and restoration of thrill in the AVF on clinical examination. The exclusion criteria include thrombosed or partially thrombosed access circuit at the time of treatment, presence of symptomatic or angiographically significant central vein stenosis that requires treatment with more than 30% residual stenosis post angioplasty, and existing stent placement within the AVF circuit. The primary endpoint of the study is access circuit primary patency at 6 months. The secondary endpoints are target lesion primary patency; access circuit-assisted primary patency; access circuit secondary patency at 3, 6, and 12 months; target lesion restenosis rate at 6 months; total number of interventions; complication rate; and cost-effectiveness. The trial is supported by Concept Medical. DISCUSSION: This study will evaluate the clinical efficacy and safety of SCB compared to PBA in the treatment of AVF stenosis in hemodialysis patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04409912 . Registered on 1 June 2020.

World's First Experience Treating TASC II C and D Tibial Occlusive Disease Using the Selution SLR Sirolimus-Eluting Balloon: Six-Month Results From the PRESTIGE Study.

PURPOSE: The performance of sirolimus-coated devices has not been studied in patients with chronic limb-threatening ischemia patients. PRESTIGE aims to investigate the 6-month efficacy and safety profile of the Selution Sustained Limus Release (SLR) sirolimus-eluting balloon for treatment of TASC II C and D tibial occlusive lesions in patients with CLTI. MATERIALS AND METHODS: PRESTIGE is a pilot prospective, nonrandomized, single-arm, multi-investigator, single-center clinical study. Endpoints were adverse event-free survival at 1 month, technical success rate, primary tibial patency at 6 months, limb salvage success, target lesion revascularization (TLR), and amputation free survival (AFS). RESULTS: A total of 25 patients were included. There were 17 (68.0%) males; mean age, 63.7±9.73 years. CLTI severity was based on the Rutherford scale (R5=25/25; 100.0%). Significant comorbidities included diabetes mellitus (n=22; 88.0%) and end-stage renal failure (n=11; 44.0%). A total of 33 atherosclerotic lesions were treated (TASC II D=15 (45.5%)). Mean lesion length treated was 191±111 mm. Technical success was 100%. Primary tibial patency at 6 months was 22/27 (81.5%) and freedom from clinically driven TLR was 25/30 (83.3%). AFS was 21/25 (84.0%; 3 deaths and 1 major lower extremity amputation). Mean Rutherford score improved from 5.00 at baseline to 1.14±2.10 (p<0.05) at 6 months. There was a wound healing rate of 13/22 (59.1%) and 17/21 (81.0%) at 3 and 6 months respectively. CONCLUSIONS: Selution SLR drug-eluting balloon is a safe and efficacious modality in treating complex tibial arterial occlusive lesions in what is an otherwise frail cohort of CLTI patients, with a high prevalence of diabetes and end-stage renal failure. Technical and clinical success rates are high and 6-month target lesion patency and AFS are more than satisfactory.

Single Asian Center Experience Using the Flixene™ Early Cannulation Graft for Hemodialysis Access Creation.

BACKGROUND: The aim of this study was to review the efficacy of the Flixene™ (Atrium™, Hudson, NH, USA) hemodialysis arterio-venous graft (AVG) in a multiethnic Asian cohort of patients with end-stage renal failure (ESRF). Primary outcome was graft primary patency rate and secondary end points included graft usability, time to cannulation, reinterventions required for access salvage, complications, and patient mortality. METHODS: Single-center, single-arm, multi-investigator nonrandomized retrospective study. Patients with ESRF who underwent Flixene™ graft implantation over a two-year period (January 2017 - December 2018) were included to allow at least one-year follow-up. Demographics, procedural and follow-up data were collected from the hospital electronic medical records. RESULTS: About 48 patients (49 AVG) were included. There were 24 (50%) men; mean age 63.7 (IQR 58.2-71.3) years. Technical success rate was 45/49 (91.8%); 4/49 (8.2%) AVG created did not reach cannulation. 11/49 (22.4%) and 28/49 (57.1%) achieved cannulation within 1 and 2 weeks, respectively. 6- and 12- month primary patencies were 33.5% and 19.6%, respectively. Primary-assisted patency rates were 46.6% and 29.6% at the same time intervals. Secondary patency rate was 77.6% and 63.9% at 6 and 12 months, respectively. There were 6 (12.2%) graft infections requiring explant and one-year mortality was 14%. CONCLUSIONS: Our experience with the Flixene™ early cannulation graft is comparable with other AVGs in terms of patency and infection rates. However, early cannulation rates are lower than in other case series.

Early results of an Asian prospective multicenter VenaSeal real-world postmarket evaluation to investigate the efficacy and safety of cyanoacrylate endovenous ablation for varicose veins.

OBJECTIVE: The aim of A Singapore VenaSeal Real-World Post-Market Evaluation Study (ASVS) was to evaluate the performance of cyanoacrylate closure (CAC) for varicose veins in a prospective multiracial Singaporean Asian cohort. We report early clinical and patient satisfaction outcomes at 3 months after intervention. METHODS: There were 100 patients (151 legs; 156 truncal veins) who underwent CAC between April and December 2018. Of the 151 legs, 49 (32.5%) were treated for great saphenous vein (GSV) incompetence, 96 (63.6%) for bilateral GSV incompetence, 1 (0.7%) for small saphenous vein (SSV) incompetence, and 5 (3.3%) for combined unilateral GSV and SSV reflux. At baseline, 68 legs (45.0%) had C4 to C6 disease, and 67 legs (44.4%) had concomitant multiple stab avulsions. Patients were reviewed at 2 and 12 weeks by duplex ultrasound to check for venous recanalization (defined as ≥5 cm in length), pain score, revised Venous Clinical Severity Score, EuroQol-5 Dimension questionnaire score, Aberdeen Varicose Vein Questionnaire score, 14-item Chronic Venous Insufficiency Questionnaire (CIVIQ-14) for quality of life measures, and patient satisfaction. Time to return to work and normal activities were also recorded. RESULTS: There were 59 female patients, and mean age was 60.1 ± 12.7 years. There was 100% technical success. Patients tolerated the procedure well and reported low periprocedural pain (mean pain score, 2.9 [range, 0-9]). Patient surveys at the 3-month interval showed high satisfaction rates, with 72 of 91 (79.1%) being extremely or very satisfied. By day 10, of 100 patients, 93 (93%) resumed daily activities, whereas 36 (36%) had returned to work. At 2 weeks, GSV and SSV were completely occluded in 150 of 150 (100%) and 6 of 6 (100%) veins, respectively. At 3 months, GSV and SSV occlusion rates were 140 of 141 (99.3%) and 6 of 6 (100%), respectively. Transient superficial phlebitis was reported in 27 of 151 (18 %) legs, which was self-limited. At 3 months, revised Venous Clinical Severity Score improved from 5.00 (range, 1.00-18.00) to 1.00 (0.00-10.00; P < .001); EuroQol-5 Dimension score, from 0.686 (-0.382 to 1.00) to 1.00 (0.12-1.00; P < .001); Aberdeen Varicose Vein Questionnaire score, from 17.14 (1.29-61.15) to 4.83 (0.00-57.12; P < .001); and 14-item Chronic Venous Insufficiency Questionnaire, from 19.64 (1.79-73.21) to 7.14 (0.00-51.79; P < .001). CONCLUSIONS: CAC has a high safety profile and is an effective way to block refluxing truncal veins in Asian patients at early follow-up. Patients are highly satisfied and report low postoperative pain. There is significant continued quality of life improvement at 3 months. Early results are encouraging, but we await further prospective long-term follow-up from the study.

Exit site complications following cyanoacrylate glue endovenous ablation of incompetent truncal veins for chronic venous insufficiency.

In the last 5 years, the use of nonthermal, nontumescent endovenous ablation such as cyanoacrylate glue (CAG) for treatment of chronic venous insufficiency has gained global popularity. This case series discusses the presentation and management of delayed access sheath site infections in patients who have undergone CAG therapy. The authors believe such adverse effects are related to granuloma formation owing to a hypersensitivity reaction to CAG at the puncture exit site. The endovenous surgeon should be aware of preventing glue spillage into the subcutaneous space at the access site during treatment, to minimize the risk of this complication developing.

Early (6 months) results of a pilot prospective study to investigate the efficacy and safety of sirolimus coated balloon angioplasty for dysfunctional arterio-venous fistulas: MAgicTouch Intervention Leap for Dialysis Access (MATILDA) Trial.

BACKGROUND: The aim of this pilot study was to evaluate the safety and efficacy of the MagicTouch™ sirolimus-coated balloon (SCB) catheter (Concept Medical Inc., Tampa, FL, US) on improving the patency of failing arterio-venous fistulas (AVF) with de novo and recurrent stenoses. MATILDA reports early outcomes at 3- and 6 months post intervention. METHODS: Single-centre, single-arm prospective pilot study of 33 (18 males; mean age 64.7±11.6 years) end-stage renal failure Asian patients with a dysfunctional AVF, who underwent SCB angioplasty between May 2019-January 2020. All procedures were performed under local anaesthetic without sedation and as day surgery. All patients were prescribed dual antiplatelet therapy for 3 months and followed up with Duplex ultrasound at 3 and 6 months. RESULTS: 47 stenotic target lesions treated and 24/33 (72.7%) patients were for restenosis. Main indications for intervention was low/dropping access flow (21/33; 63.6%) and most common target lesion was in the juxta-anastomosis (19/47; 40.4%). There was 100% technical and procedural success. There were no peri-procedural complications related to the SCB. The target lesion primary patency rates at 3 and 6 months were 46/47 (97.9%) and 29/35 (82.9%) respectively. Circuit access patency rates at 3 and 6 months were 31/33 (93.9%) and 17/25 (68%) respectively. There was one (2.9%) death at 6 months and 4/33 (12.1%) overall to date, all from patients' underlying co-morbidities. CONCLUSIONS: SCB angioplasty for dysfunctional AVF circuits is a safe and efficacious modality in Asian haemodialysis patients at six months comparable if not better than the paclitaxel data reported to date in the literature.

The Modified Frailty Index Does Not Predict Mortality After Major Lower Extremity Amputation for Peripheral Arterial Disease in an Asian Population.

BACKGROUND: Patients with critical limb ischemia (CLI) who undergo major lower extremity amputation (LEA) have been associated with high one-year mortality rates. Previous western-based studies have identified risk factors that exponentiate these poor outcomes, including nonambulatory status and cardiovascular morbidity. We assessed the effect of frailty, using the modified frailty index (mFI) in a cohort undergoing major LEA for CLI to predict mortality, perioperative complications, and unplanned readmissions in a tertiary institution from Singapore. METHODS: Data on patients who had undergone major LEA from January 2016 to December 2017 were collected retrospectively. Inclusion criteria were below-knee amputations (BKAs) or above-knee amputations (AKAs) performed for peripheral arterial disease-related tissue loss or sepsis only. Patients were categorized into 3 risk groups based on the 11-variable mFI: low mFI, 0-0.27; moderate mFI, 0.36-0.54; and high mFI ≥0.63. Univariate and multivariate analysis was performed using logistic regression analysis. RESULTS: 211 patients underwent major LEA, of whom 133 (63.0%) had undergone BKA. The mean mFI was 0.41 (range 0-0.81). 84/211 (39.8%) died within 1 year after the procedure, with mortality rates of 25/65 (38.4%), 49/127 (38.6%), and 10/19 (52.6%) in the low-, moderate-, high-mFI categories, respectively. High and moderate mFI had failed to demonstrate an increased risk of mortality when compared with the low-mFI group (P > 0.05). 91/211 (43.1%) patients had perioperative complications, whereas 27/211 (12.8%) patients were readmitted within 30 days of discharge. Myocardial infarction, chronic kidney disease, and atrial fibrillation were found to be predictive of poor outcomes after major LEA. CONCLUSIONS: Frailty as measured with the mFI did not predict outcome after major LEA. This could be due to confounding effects such as high prevalence of renal dysfunction and the constancy of diabetes and peripheral vascular disease in this population that would reduce the differentiation of patients using the mFI.

Use of Paclitaxel Coated Drug Eluting Technology to Improve Central Vein Patency for Haemodialysis Access Circuits: Any Benefit?

PURPOSE: Central venous stenosis is a recurring problem affecting dialysis access patency. Increasing evidence suggests that the use of drug-coated balloons (DCBs) improves target lesion primary patency (TLPP) in dialysis access. However, few studies have investigated the use of DCBs specifically in central venous stenosis. Thus, this study presents our initial experience with DCBs in the central vein of a dialysis access circuit. MATERIALS AND METHODS: This is a retrospective cohort study of all hemodialysis patients who underwent central vein angioplasty with DCB between February 2017 and March 2018 at Singapore General Hospital. We compared the primary patency post DCB angioplasty to the primary patency of the patient's previous plain old balloon angioplasty (POBA). RESULTS: We observed a 100% anatomic and procedural success rate with no complications. The median follow-up period was 151 days (interquartile range, 85.5-234 days) and no patients were lost to follow-up. The 30- and 90-day TLPPs after DCB were 93.3% and 75.7%, respectively. The mean primary patency in our study group post-DCB during the follow-up period was 164 days (vs. 140 days in the POBA group). However, no statistically significant difference was detected. CONCLUSION: DCB showed a similar TLPP to that for POBA in treating central venous stenosis with a trend toward a longer re-intervention-free period for DCB. However, there were numerous confounding factors and a well-designed randomized controlled trial is warranted to assess the true utility of DCB in treating central venous stenosis.

Maximally Disfiguring Surgery for Forefoot Osteomyelitis: Time for a Rethink?

The treatment of choice for diabetic foot osteomyelitis is surgical debridement and targeted antibiotics with or without revascularization, depending on vascular status. In our society, debridement is done by either a vascular or orthopedic surgeon, and the common teaching is that generous amputation of bone with the accompanying soft tissue envelope is essential for adequate source control and to prevent recurrence (which remains as high as 30% even with this approach). Most of our patients undergo formal ray amputation through the metatarsal neck, while a few get digital amputations through the interphalangeal joints. Many of the resultant wounds cannot be closed and are left to heal by secondary intention. These amputations invariably alter the biomechanics of the foot and leave large and slow-healing open wounds, which have associated adverse psychosocial impacts. We describe 2 cases of patients who had osteomyelitis in the region of the forefoot who underwent complete bony resections of the osteomyelitis but with sparing of the soft tissue envelopes with good outcomes, and we challenge the dogma that maximal debridement of soft tissue must accompany debridement of necrotic and infected bone.

A systematic review, meta-analysis, and meta-regression of the efficacy and safety of endovascular arteriovenous fistula creation.

OBJECTIVE: The percutaneous endovascular approach to arteriovenous fistula (AVF) creation is a minimally invasive alternative to surgical AVF creation. This systematic review and meta-analysis aimed to investigate the efficacy and safety of endovascular AVF creation in patients with end-stage renal disease. METHODS: This study conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search was performed on major databases to identify relevant articles. Meta-analysis of proportions and meta-regression were conducted. RESULTS: Seven studies totaling 300 patients were included, of which four evaluated the everlinQ (TVA Medical, Austin, Tex) and three employed the Ellipsys (Avenu Medical, San Juan Capistrano, Calif) systems. The overall technical success rate was 97.50% (95% confidence interval [CI], 94.98-99.31%; I2 = 0.00%; P = .487). The 90-day maturation rate was 89.27% (95% CI, 84.00-93.66%; I2 = 21.29%; P = .283), and the 6-month patency and 12-month patency were 91.99% (95% CI, 87.98-95.35%; I2 = 0.00%; P = .780) and 85.71% (95% CI, 79.90-90.71%; I2 = 0.00%; P = NS), respectively. The overall procedure-related complication rate was 5.46% (95% CI, 0.310-14.42%; I2 = 81.21%; P = .000). Meta-regression was conducted on the pooled rates of technical success and complication, showing that age, diabetes, white race, hypertension, on dialysis, and body mass index were not significant sources of heterogeneity. CONCLUSIONS: Current endovascular AVF systems appear to be effective and safe. However, given the lack of head-to-head comparative analyses with surgical AVF creation, superiority cannot be established.

A systematic review and meta-analysis of drug-coated balloon versus conventional balloon angioplasty for dialysis access stenosis.

BACKGROUND: Arteriovenous fistulas for patients undergoing hemodialysis (HD) are at high risk of stenosis. Despite conventional balloon angioplasty (CBA), restenosis rates are high. The use of a drug-coated balloon (DCB) may offer an alternative to reduce restenosis. METHODS: This study has been performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search on MEDLINE, Embase, and the Cochrane Library was performed to identify articles evaluating DCB angioplasty for patients with HD access stenosis. Risk ratios (RRs) of primary patency were pooled, and relevant subgroup and sensitivity analyses were conducted. RESULTS: There were 17 studies (8 randomized controlled trials [RCTs], 9 cohort studies) included, comprising a total of 1113 stenotic dialysis accesses, of which 54.7% underwent DCB angioplasty and 45.3% underwent CBA. There was a significantly superior 6-month (RR, 0.57; 95% confidence interval [CI], 0.44-0.74; P < .00001; I2 = 62%) and 12-month (RR, 0.73; 95% CI, 0.63-0.84; P < .0001; I2 = 53%) primary patency in the DCB angioplasty group in comparison to the CBA group (71.0% vs 49.2% at 6 months; 44.2% vs 20.6% at 12 months). Subgroup analyses of study design (RCTs, cohort studies) showed similar trends. Sensitivity analyses by excluding one poor-quality RCT and those employing the crossover analysis design also showed similar results. Studies investigating central venous stenosis showed significantly better 6-month (RR, 0.57; 95% CI, 0.41-0.79; P = .0009; I2 = 67%) and 12-month (RR, 0.69; 95% CI, 0.56-0.85; P = .0004; I2 = 64%) primary patency in the DCB angioplasty group in comparison to the CBA group. The pooled rate of minor complications was low in both the DCB (1.1%) and CBA (0.9%) groups. CONCLUSIONS: DCB angioplasty appears to be a better and safe alternative to CBA in treating patients with HD stenosis in terms of 6- and 12-month primary patency. However, a larger trial is warranted to establish these findings.

Fenestrated Endovascular Repair of Zones 1 and 2 Aortic Arch Pathologies.

BACKGROUND: Surgical management of aortic arch pathologies is complex, and endovascular developments have now enabled total or hybrid endovascular aortic arch repair. We present our early experience with fenestrated aortic arch repairs in Ishimaru zones 1 and 2 pathologies. METHODS: In a single tertiary institution, all consecutive endovascular aortic arch repairs were reviewed. A preoperative computed tomography aortogram was performed to assess anatomic suitability, which we defined as having a proximal sealing zone with a maximum diameter of 38 mm and minimum length of 20 mm, absence of significant aortic tortuosity, and suitable sealing zones in target vessels. RESULTS: From September 2015 to February 2018, 5 cases of fenestrated aortic arch endovascular repairs were performed. There were 3 male patients. The patients were between 57 and 83 years old, all of whom were American Society of Anesthesiologists (ASA) class II or III. Indications for surgery included aortic arch aneurysms (n = 3), a symptomatic aortic dissection, and a left subclavian artery aneurysm. Three patients had a scallop to the innominate artery, and one patient had a scallop to the left common carotid artery. Fenestrations were made to 3 left common carotid arteries and 3 left subclavian arteries. In 2 patients, a left carotid-subclavian bypass was performed, and the left subclavian artery origin occluded with a vascular plug. Technical success was 100%. One patient developed a right occipital infarct and acute myocardial infarction. The mean duration of surgery was 164 min, and the mean length of stay was 4.2 days. The mean follow-up period was 14.4 months. CONCLUSIONS: The use of fenestrated grafts in the aortic arch is a feasible treatment option. However, certain limitations still exist, and preoperative planning is important in ensuring clinical success. Although this procedure appears feasible in the short term, long-term results and durability remain to be seen.

Case Report of Ethanol and Cyanoacrylate Embolisation of a Recurrent Uncontrollable Torrentially Bleeding Arteriovenous Malformation of the Finger.

INTRODUCTION: In general, arteriovenous malformations (AVMs) are extremely rare, with an incidence of only 1 in 100,000. They are rarer still in the hands and present variably with bleeding, heaviness, a pulsatile mass, pain, ulceration, or necrosis. REPORT: The case of a 25 year old man with a rapidly bleeding right thumb AVM is presented. Bleeding was torrential and life threatening within a matter of seconds. He had previously undergone surgical ligation and embolisation twice at another centre, without success. At presentation, he had no thumb function and the bones of the thumb were exposed. An angio-embolisation was performed with ethanol and cyanoacrylate as the embolic agent. This was done using direct puncture into the AVM and also with a transarterial approach with microcatheters inserted into various unnamed branches feeding the AVM. Non-target embolisation and reflux was prevented by deploying a pneumatic tourniquet and mechanical elastic bands to confine the flow of the embolic agents within the AVM. Re-aspiration of the embolic agent post-embolisation was also performed to prevent local/systemic ethanol toxicity. Haemostasis was achieved without the need for further compression. A right thumb disarticulation was subsequently performed and the patient expressed great satisfaction with the outcome. DISCUSSION: AVMs in the hand are particularly challenging to treat owing to the need to preserve function of the myriad tissues and structural units that enable the many hand movements involved in activities of daily living. Even a partial loss of function may be disabling or poorly tolerated. The mainstays of treatment are embolisation, sclerotherapy, and surgical ligation/resection, all of which carry the potential for ischaemic injury to muscle and soft tissue. A holistic approach to management is desirable prior to selecting the appropriate management plan.

Catheter-related complications and survival among incident hemodialysis patients in Singapore.

INTRODUCTION:: Hemodialysis is the main modality of renal replacement therapy in Singapore. However, a majority of the patients in Singapore are initiated on hemodialysis via a catheter. This study examines the complication rates and factors predicting catheter-related bloodstream infections and mortality rates in patients who were initiated on hemodialysis at our institution. METHODS:: This is a single-center retrospective analysis of incident hemodialysis patients who were initiated on renal replacement therapy between 1 January 2010 and 31 December 2012. Catheter-related bloodstream infection risk factors, organisms, and associated mortality were analyzed. RESULTS:: The catheter-related bloodstream infection and exit site infection incidence rates were 0.75 and 0.50 per 1000 catheter days, respectively. The mean duration to first catheter-related bloodstream infection episode was 182.47 ± 144.04 catheter days. Prolonged catheter duration was found to be a risk factor for catheter-related bloodstream infection. Compared to patients initiated on dialysis via arteriovenous fistula, initiation of dialysis via catheter is strongly associated with increased mortality (6.0% vs 14.5%; p = 0.02). In particular, the presence of diabetes mellitus and development of catheter-related bloodstream infection was associated with increased mortality ( p = 0.04 and 0.05, respectively). In addition, patients who began hemodialysis before being seen by a nephrologist were associated with decreased mortality (3.4% vs 13.0%; p = 0.03). CONCLUSION:: In conclusion, prolonged duration of catheter insertion is found to be a risk factor for catheter-related bloodstream infection in hemodialysis patients, and its development is associated with increased mortality. Early referral to a nephrologist and creation of arteriovenous fistula in pre-end-stage renal disease patients are pivotal in improving the outcomes of patients.

Metformin Inhibits Cellular Proliferation and Bioenergetics in Colorectal Cancer Patient-Derived Xenografts.

There is increasing preclinical evidence suggesting that metformin, an antidiabetic drug, has anticancer properties against various malignancies, including colorectal cancer. However, the majority of evidence, which was derived from cancer cell lines and xenografts, was likely to overestimate the benefit of metformin because these models are inadequate and require supraphysiologic levels of metformin. Here, we generated patient-derived xenograft (PDX) lines from 2 colorectal cancer patients to assess the properties of metformin and 5-fluorouracil (5-FU), the first-line drug treatment for colorectal cancer. Metformin (150 mg/kg) as a single agent inhibits the growth of both PDX tumors by at least 50% (P < 0.05) when administered orally for 24 days. In one of the PDX models, metformin given concurrently with 5-FU (25 mg/kg) leads to an 85% (P = 0.054) growth inhibition. Ex vivo culture of organoids generated from PDX demonstrates that metformin inhibits growth by executing metabolic changes to decrease oxygen consumption and activating AMPK-mediated pathways. In addition, we also performed genetic characterizations of serial PDX samples with corresponding parental tissues from patients using next-generation sequencing (NGS). Our pilot NGS study demonstrates that PDX represents a useful platform for analysis in cancer research because it demonstrates high fidelity with parental tumor. Furthermore, NGS analysis of PDX may be useful to determine genetic identifiers of drug response. This is the first preclinical study using PDX and PDX-derived organoids to investigate the efficacy of metformin in colorectal cancer. Mol Cancer Ther; 16(9); 2035-44. ©2017 AACR.