The Retrograde Basilic Approach for Balloon-Assisted Maturation of Brachiocephalic Arteriovenous Fistulas.

PURPOSE: To assess the feasibility and outcomes of an approach utilizing transbasilic access for balloon-assisted maturation (BAM) of brachiocephalic arteriovenous fistulas (BCAVFs). MATERIALS AND METHODS: This retrospective analysis comprised 28 patients (mean age, 63 years ± 10.8) who underwent endovascular treatment of their immature BCAVFs via a basilic approach from December 2016 to December 2018. The mean age of the BCAVFs was 3.3 months ± 1.4 at the time of BAM. Other demographic data, vascular access characteristics, procedural data, technical and clinical success rates, and adverse events were also evaluated. RESULTS: All patients had inflow juxta-anastomotic stenoses, with 4 patients (14%) having concomitant outflow tract stenoses and 1 patient (4%) having a short-segment occlusion at the stenotic juxta-anastomotic segment. Technical success was achieved in 27 patients (96%). The mean diameter of the largest balloon used was 5.7 mm ± 0.6. Clinical success was achieved in 22 patients (79%), with 6 patients (21%) requiring a subsequent additional intervention before successful cannulation. No perioperative adverse events were observed. CONCLUSIONS: The retrograde basilic approach is feasible, safe, and effective for BAM of BCAVFs.

Infected femoral pseudoaneurysms in intravenous drug abusers: a decade of experience from a Singapore tertiary centre.

INTRODUCTION: A pseudoaneurysm (or false aneurysm) is a haematoma that communicates with an artery through a disruption in the arterial wall. The femoral artery is the most common injection site among drug users, and infected femoral pseudoaneurysms are the most common vascular complications. METHODS: A retrospective review of medical records of intravenous drug abusers (IVDAs) who presented with infected femoral pseudoaneurysms from January 2006 to December 2016 was carried out. Patients who had pseudoaneurysms due to other aetiologies or trauma were excluded. RESULTS: A total of 27 patients with infected femoral pseudoaneurysms were identified. The majority were male (92.6%) and of Malay ethnicity (55.6%). Median age was 50 (range 31-62) years. Commonly abused drugs were buprenorphine (or Subutex; 59.3%) and midazolam (or Dormicum; 51.9%). Groin pain and swelling (100.0%), fever (66.7%) and presence of a pulsatile mass (51.9%) were the most common presenting symptoms. Diagnosis was confirmed via computed tomography angiography in all patients. 25 patients underwent upfront arterial ligation with debridement, among whom three patients required concurrent surgical revascularisation. Only two patients underwent ultrasonography-guided thrombin injection - one eventually required surgery and the other was lost to follow-up. Postoperative complications included wound infection (42.3%), bleeding (11.5%) and necrotising fasciitis eventually resulting in limb loss (3.8%). There were no associated mortalities. CONCLUSION: Infected pseudoaneurysms in IVDAs pose a unique challenge to vascular surgeons. We found that simple ligation and debridement was a safe and effective option for such patients.

Early and Midterm Experience With the Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Asian Patients With Chronic Limb-Threatening Ischemia: One-Year Clinical and Imaging Outcomes From the DISAPEAR Registry.

Purpose: To report an experience with the Absorb bioresorbable vascular scaffold (BVS) in an Asian cohort with chronic limb-threatening ischemia (CLTI) from the DISAPEAR (Drug Impregnated Bioresorbable Stent in Asian Population Extremity Arterial Revascularization) registry. Materials and Methods: A retrospective analysis was conducted of 41 patients (median age 64 years; 23 men) with CLTI owing to >50% de novo infrapopliteal lesions (n=53) treated with the Absorb BVS between August 2012 and June 2017. The majority of patients (37, 90%) had diabetes, 24 (59%) had ischemic heart disease, and 39 (95%) had Rutherford category 5/6 ischemia with tissue loss. The mean lesion length was 22.7±17.2 mm; 10 (24%) lesions were severely calcified. Assessments included technical success, primary patency, freedom from clinically-driven target lesion revascularization (CD-TLR), amputation-free survival, limb salvage, complete wound healing, resolution of rest pain, and resolution of CLTI without TLR at 6 and 12 months after the index intervention. Results: Overall, 69 scaffolds were implanted in the 53 lesions, with 100% technical success. There were no deaths within 30 days of the index procedure. The primary patency rates at 6 and 12 months were 95% and 86%, respectively. The corresponding rates of freedom from CD-TLR were 98% and 93%, respectively. Freedom from major amputation was 98% at both time points, and amputation-free survival was 93% and 85% at 6 and 12 months after the index procedure. Wound healing occurred in 31 patients (79%) with Rutherford category 5/6 ischemia by the end of 12 months. Conclusion: The Absorb BVS demonstrated good 1-year patency and clinical outcomes in CLTI patients with complex infrapopliteal disease.

Cord Lining Mesenchymal Stem Cells Have a Modest Positive Effect on Angiogenesis in Hindlimb Ischemia.

Purpose: We investigated the use of human Cord Lining Mesenchymal Stem Cells (CL-MSCs) (US Patent number 9,737,568), in a rabbit hindlimb ischemia model, and evaluated their potential in stimulating neovascularization. Allogenic human CL- MSCs could potentially be used to treat patients with lower limb ischemia and non-healing wounds. Methods: Twenty rabbits were divided into two separate groups. We created a hindlimb ischemia model surgically. At 21 and 49 days post-operatively, animals in the treatment group were injected with CL-MSCs (500,000 cells per 0.2 ml on each site) at 10 different sites (Quadriceps- 4 sites, Hamstrings- 4 sites and Calf--2 sites) in the hindlimb muscles. The control group received only saline injection to the corresponding sites at the same time point as the treatment group. We then evaluated the effects of treatment on neovascularization by angiography, laser doppler perfusion imaging, as well as by histology. We evaluated the tissue samples for any signs of local immune reaction to the cell implantation. We also observed the rabbit clinically for any adverse effects after treatment. Results: We found a higher number of CD31 positive cells in the treatment group, with a greater number of capillaries found in the treated muscles. The Rectus Femoris demonstrated a median vessel count/muscle fiber of 0.121 for the treatment group, compared to 0.076 in the control group (median difference 0.04; 95% CI 0.001-0.11; p = 0.041). The Gastrocnemius demonstrated a median vessel count/muscle fiber of 0.175 for the treatment group, compared to 0.089 in the control group (median difference 0.087; 95% CI -0.006 to 0.234; p = 0.07). Blood perfusion quantification through Laser Doppler Perfusion Imaging (LDPI) also demonstrated a non-statistically significant increase in perfusion in favor of the treatment group. CL-MSCs demonstrated no toxicity associated morbidity and minimal local immune reaction to implantation. Conclusion: CL-MSCs have a positive effect on angiogenesis in a rabbit hindlimb ischemia model. This preliminary data is encouraging and paves the way for future large animal studies or for clinical trials.

Defying hard-to-heal wounds with an early antibiofilm intervention strategy: 'wound hygiene'.

Biofilm has been implicated as a barrier to wound healing and it is widely accepted that the majority of wounds not following a normal healing trajectory contain biofilm. Therefore, strategies that inform and engage clinicians to reduce biofilm and optimise the wound tissue environment to enable wound progression are of interest to wound care providers. In March 2019, an advisory board was convened where experts considered the barriers and opportunities to drive a broader adoption of a biofilm-based approach to wound care. Poor clarity and articulation of wound terminology were identified as likely barriers to clinical adoption of rigorous and proactive microbial decontamination that is supportive of wound healing advancement. A transition to an intuitive term such as 'wound hygiene' was proposed to communicate a comprehensive wound decontamination plan with an associated message of expected habitual routine. 'Wound hygiene', is a relatable concept that supports meticulous wound practice that addresses barriers to wound healing, such as biofilm, while aligning with antimicrobial stewardship programmes.

Novel use of the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts: a case series.

INTRODUCTION: The aim of this prospectively collected case series is to demonstrate a novel technique of using the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts. METHODS: The analysis comprised 11 procedures in 9 patients from 1 July to 31 December 2016 in which the ClariVein catheter was used in combination with urokinase. Demographic data, procedural data, technical and clinical success rates, and complications were evaluated. The primary and secondary patency rates at 1 and 3 months were also analyzed. RESULTS: In the 11 procedures performed, the technical and clinical success was 100%. The mean procedural time was 66.8 minutes (range 50-90 minutes), and the mean amount of urokinase administered was 87,000 units. The primary unassisted patency rates at 1 and 3 months were 81.8% and 63.6%, respectively. The secondary patency rates at 1 and 3 months were 90.9% and 81.8%, respectively. Perforation occurred after balloon angioplasty in 1 (9.1%) of the 11 procedures, for which covered stenting was performed. No major complications occurred. CONCLUSIONS: The combination use of the ClariVein catheter with urokinase for pharmacomechanical thrombolysis in thrombosed hemodialysis grafts is a feasible and safe method that can be performed in a relatively short duration. Our early results have shown 100% technical and clinical success. This case series serves as a platform for an upcoming prospective study to further evaluate this method.

Midterm Outcomes From a Pilot Study of Percutaneous Deep Vein Arterialization for the Treatment of No-Option Critical Limb Ischemia.

PURPOSE: To report the initial clinical experience with percutaneous deep vein arterialization (PDVA) to treat critical limb ischemia (CLI) via the creation of an arteriovenous fistula. METHODS: Seven patients (median age 85 years; 5 women) with CLI and no traditional endovascular or surgical revascularization options (no-option CLI) were recruited in a pilot study to determine the safety of PDVA. All patients were diabetic; 4 had Rutherford category 6 ischemia. Six were classified at high risk of amputation based on the Society for Vascular Surgery WIfI (wound, ischemia, and foot infection) classification. The primary safety endpoints were major adverse limb events and major adverse coronary events through 30 days and serious adverse events through 6 months. Secondary objectives included clinical efficacy based on outcome measures including thermal measurement, transcutaneous partial pressure of oxygen (TcPO2), clinical improvement at 6 months, and wound healing. RESULTS: The primary safety endpoints were achieved in 100% of patients, with no deaths, above-the-ankle amputations, or major reinterventions at 30 days. The technical success rate was 100%. Two myocardial infarctions occurred within 30 days, each with minor clinical consequences. All patients demonstrated symptomatic improvement with formation of granulation tissue, resolution of rest pain, or both. Complete wound healing was achieved in 4 of 7 patients and 5 of 7 patients at 6 and 12 months, respectively, with a median healing time of 4.6 months (95% confidence interval 84-192). Median postprocedure peak TcPO2 was 61 mm Hg compared to a preprocedure level of 8 mm Hg (p=0.046). At the time of wound healing, 4 of 5 of patients achieved TcPO2 levels of >40 mm Hg. There were 2 major amputations, 1 above the knee after PDVA thrombosis and 1 below the knee for infection. Three patients died of causes unrelated to the procedure or study device at 6, 7, and 8 months, respectively. Limb salvage was 71% at 12 months. CONCLUSION: PDVA is an innovative approach for treating no-option CLI and represents an alternative option for the "desert foot," potentially avoiding major amputation. Our results demonstrate its safety and feasibility, with promising early clinical results in this small cohort.

Endovascular retrograde recanalization in Asian critical limb ischaemia patients.

BACKGROUND: To evaluate endovascular retrograde recanalization of critical limb ischaemia (CLI) patients with chronic total occlusions (CTOs) in an Asian population. METHODS: We conducted a single centre-based retrospective review of CLI patients with CTOs who had undergone endovascular retrograde recanalization using the subintimal arterial flossing with antegrade-retrograde intervention technique. RESULTS: A total of 40 CLI patients with CTOs underwent endovascular intervention. The median age was 71 years; 67.5% were males and Chinese accounted for 65% of the patients, of which 55% were in Rutherford category 6, 37.5% in category 5 and 7.5% in category 4. Antegrade-retrograde access was performed via the femoral artery in 39 cases and the brachial artery in one case for the proximal puncture, and the following arteries for the distal puncture: superficial femoral, n = 4 (10%); popliteal, n = 4 (10%); anterior tibial, n = 12 (30%); dorsalis pedis, n = 9 (22.5%); peroneal, n = 4 (10%) and posterior tibial, n = 7 (17.5%). Technical success was high at 92.5% (n = 37). After intervention, 25% (n = 10) had below-knee triple vessel runoff, 52.5% (n = 21) had double vessel runoff and 15.0% (n = 6) had single vessel runoff. Stenting for target vessel dissections was required in 12 patients. There were two cases of significant bleeding; one common femoral artery pseudoaneurysm was treated with ultrasound-guided thrombin injection and another case of distal puncture site bleeding only required compression. Limb salvage at 1 year was 92.5% (n = 37). CONCLUSION: The subintimal arterial flossing with antegrade-retrograde intervention technique is safe with high technical success rates and acceptable outcomes in Asian CLI patients with CTOs.

Spectral analysis of bowel sounds in intestinal obstruction using an electronic stethoscope.

AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possible intestinal obstruction based on symptoms, signs, and radiological findings. A 3M™ Littmann(®) Model 4100 electronic stethoscope was used in this study. With the patients lying supine, six 8-second recordings of bowel sounds were taken from each patient from the lower abdomen. The recordings were analysed for sound duration, sound-to-sound interval, dominant frequency, and peak frequency. Clinical and radiological data were reviewed and the patients were classified as having either acute, subacute, or no bowel obstruction. Comparison of bowel sound characteristics was made between these subgroups of patients. In the presence of an obstruction, the site of obstruction was identified and bowel calibre was also measured to correlate with bowel sounds. RESULTS: A total of 71 patients were studied during the period July 2009 to January 2011. Forty patients had acute bowel obstruction (27 small bowel obstruction and 13 large bowel obstruction), 11 had subacute bowel obstruction (eight in the small bowel and three in large bowel) and 20 had no bowel obstruction (diagnoses of other conditions were made). Twenty-five patients received surgical intervention (35.2%) during the same admission for acute abdominal conditions. A total of 426 recordings were made and 420 recordings were used for analysis. There was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction. In acute large bowel obstruction, the sound duration was significantly longer (median 0.81 s vs 0.55 s, P = 0.021) and the dominant frequency was significantly higher (median 440 Hz vs 288 Hz, P = 0.003) when compared to acute small bowel obstruction. No significant difference was seen between acute large bowel obstruction and large bowel pseudo-obstruction. For patients with small bowel obstruction, the sound-to-sound interval was significantly longer in those who subsequently underwent surgery compared with those treated non-operatively (median 1.29 s vs 0.63 s, P < 0.001). There was no correlation between bowel calibre and bowel sound characteristics in both acute small bowel obstruction and acute large bowel obstruction. CONCLUSION: Auscultation of bowel sounds is non-specific for diagnosing bowel obstruction. Differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction.