Anastomosis Device Research Articles

Evaluation of sutureless anastomosis after ileostomy takedown using the self-forming magnet anastomosis system in a porcine model.

Current standard of care for creation of small bowel anastomoses after a loop ileostomy reversal includes the use of stapler devices and sutures. Compression anastomosis devices have been used for decades, aimed toward improved outcomes with a "staple free" & "suture free" anastomosis. The self-forming magnet (SFM) device is a type of compression anastomosis device used to safely and effectively create an end-to-end small bowel anastomosis without the localized inflammatory response seen with sutures or staples, as no foreign bodies are left behind. A Good Laboratory Practice preclinical study using a porcine model to evaluate creating an in vivo anastomosis via magnetic compression between two segments of small bowel (jejunum or ileum) was performed. Magnetic anastomoses were compared to stapled and handsewn anastomoses. Six animals were used for the magnetic anastomosis and eight for the two control groups for a total of 14 subjects. Mean creation times were 17.1min (SD 6.06) for the SFM group, 10.3min (SD 6.55, CI 95%) for the stapled anastomosis group, and 28.3min (SD 2.63, CI 95%) for the suture anastomosis group, with a statistically significant difference among groups (p < 0.0021). All evaluated SFM anastomosis, stapled anastomosis, and handsewn anastomosis underwent a burst test with a pressure of 1.3 PSI. All six magnets used for anastomoses were naturally expelled. The range of days to expel magnets was 10-17days. Intestinal anastomoses using magnets had considerably less residual scarring and intestinal distortion than anastomoses done with either suture or staples. This preclinical study documents the safety and efficacy of creating end-to-end small bowel anastomoses after ileostomy takedown using a magnetic compression device. The result is an anastomosis free of foreign objects with less inflammation, scarring, distortion, and mural thickening than seen in sutured or stapled anastomoses.

Construction of Esophagogastric Anastomosis in Rabbits with Magnetic Compression Technique

PurposeThe magnetic compression technique (MCT) is a new surgical method that has been used for gastrointestinal anastomosis, choledochojejunostomy, and intestinal anastomosis, but there are no reports on its use for esophagogastric anastomosis. This study aimed to investigate the feasibility of using MCT to fashion esophagogastric anastomoses in rabbits. MethodsTwenty rabbits were randomized into an MCT group (study group, n = 10) and a hand-sewn group (control group, n = 10). The magnetic compression anastomosis device used in this study was made of neodymium iron boron (NdFeB) and possessed parent (PMR) and daughter (DMR) magnetic rings. To fashion the anastomosis, the PMR and DMR were inserted into the lower esophagus and gastric fundus, respectively. The coupled magnets automatically compressed the sandwiched tissues and were expelled once the anastomosis was installed. The two groups were further compared in terms of the anastomosis construction time, survival rate, and postoperative complications. One month after the anastomosis was installed, the burst pressure and gross appearance of the anastomoses were evaluated. ResultsThe anastomosis construction time in the study group was significantly shorter than that in the control group (10.50±1.58 min vs. 18.60±2.22 min; P < 0.05), and the magnetic rings were defecated out in 10.70±3.49 days. The incidence of anastomotic blockage in both the study and control groups did not differ significantly (0%, 0/10 vs. 20%, 2/10; P > 0.05). Anastomotic leakage was not found in either of the groups, and the anastomoses burst pressures were similar in the two groups. However, the magnetically compressed anastomoses in the study group had a relatively smoother gross appearance than the hand-sewn anastomoses. ConclusionThe magnetic compression anastomosis device is a safe and feasible tool for fashioning esophagogastric anastomoses in this animal model.

Differences in free flaps' reconstructions with and without coupling device for venous anastomosis.

&lt;br&gt;&lt;b&gt;Introduction:&lt;/b&gt; Introduction of the coupler devices for anastomoses of neck vessels changes planning and performance of the surgical procedures. The Rigid ring of the coupling devices keeps a vein open and less prone to occlusion. Therefore, this should improve the flap survival rate and surgery duration.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Aim:&lt;/b&gt; The aim of the study was to point out the differences in surgery planning between couplers and sutures for venous microsurgical anastomoses.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Methods:&lt;/b&gt; The medical records of 209 patients who underwent 212 microvascular free flap reconstructions from January 2011 till December 2017 were retrospectively analyzed; 103 received radial forearm free flap (RFFF); 43 - anterolateral thigh flap (ALTF); 51 - fibula free flap (FFF); 15 - iliac crest free flap (ICFF). In 189 cases, reconstruction was performed simultaneously with tumor resection and in 23 cases, reconstruction was secondary, after previous oncological treatment. Among 443 anastomoses, suturing was used for 212 arteries and 127 venous anastomoses, while coupling was used for 104 venous anastomoses.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Results:&lt;/b&gt; The mean surgery duration for suturing was 452.82 min vs 358.88 min for coupling (P&lt;0.05). Differences in flap survival and partial necrosis rates between coupling and suturing groups were not statistically significant (P&gt;0.05). Donor vessel distribution in the neck was significantly different in both groups. Estimated costs of the surgical procedures performed with and without coupler devices were not equal.&lt;/br&gt; &lt;br&gt;&lt;b&gt;Conclusions:&lt;/b&gt; The use of couplers for venous anastomosis in free flap head and neck reconstructions impacts the surgery process by shortening surgery duration which leads to cost reduction.&lt;/br&gt.

Electromagnets for an endoscopic anastomosis tool in the colon

Abstract The goal of our research work is the development of a novel endoscopic anastomosis device for the colon. One of the main challenges in this context is the application of forces at the endoscope tip to rejoin the two bowel endings. Thus, we focus on a magnetic two-part compression implant approach. The implant halves are detached from the applicator units by means of electromagnets. In this contribution we present the results of our experiments to determine the implant design with special focus on tissue compression forces and the resultant electromagnet dimensioning to estimate size requirements of the application/detachment system. To achieve the targeted compression forces derived from literature, we used cubic N52 magnetized neodymium magnets1 with a side length of 5 mm and mild steel screws. For these magnets, we evaluated a required electromagnetic repulsion force of 4.1 N. For the electromagnetic detachment system this led to the need for 166 windings for the coils on oral side, and 146 windings for the coils at the aboral side. Based on these requirements, a colonoscope diameter (~14 mm) increase of 10.6 mm on the oral side and of 12 mm on the aboral side due to the application device must be assumed. Nevertheless, this diameter still remains within the size range of other colonoscopic tools, such as e.g., circular staplers.

Animal Study of a Novel Device for Clampless Proximal Anastomosis in Coronary Bypass Surgery

PurposeLimitations of existing techniques for clampless proximal anastomosis (CPA) in coronary artery bypass grafting include air emboli and excessive bleeding. This study evaluated the safety and performance of a new device for performing CPA. DescriptionThe device includes a temporary adjustable sealing element that is connected by a catheter to a handle that controls its opening and closure. An aortic punch is mounted on the catheter and activated by a detachable handle. EvaluationSix adult female swine underwent partial coronary artery bypass grafting that included construction of a CPA using autologous arterial or venous conduits. During anastomosis construction, good sealing was achieved in all cases, and a blower was not needed in 4 of 6 animals. In the first 2 cases, the blower was intermittently used in 14 % of the entire anastomosis construction time. A mean flow rate of 140.0 ± 52.9 mL/min was measured for the arterial grafts and 666.7 ± 230.9 mL/min for the venous grafts. ConclusionsThe VIOLA device (Vascular Graft Solutions, Tel Aviv, Israel) is safe and associated with good hemostasis and minimal use of a blower during CPA construction in a swine model.

Bioabsorbable flexible elastomer of PTMC‐b‐PEG‐b‐PTMC copolymer as intestinal anastomosis scaffold

AbstractArtificial intestinal devices play an important role for intestinal anastomosis, while there is not a suitable candidate with the characteristics for this application. It is necessary to develop a biodegradable tissue‐compliant intestinal anastomosis device. Herein, the triblock copolymers of poly(trimethylene carbonate)‐b‐polyethylene glycol‐b‐poly(trimethylene carbonate) (PTMC‐b‐PEG‐b‐PTMC) were prepared with different degradation properties by adjustable the block proportions. These copolymers were electrospun to fabricate the intestinal anastomosis scaffolds. Considering the degradation, mechanical properties, and hydrophilicity of the triblock copolymers, the scaffolds with PEG content ranging from 10% to 20% were suitable for implantation evaluation. The flexible scaffolds with PEG content of 15% were selected to perform animal experiments. The results showed that the scaffolds loaded with triclosan could effectively promote the healing of intestinal wounds and reduce the probability of intestinal fistula, intestinal obstruction, and other complications. The scaffolds are a promising candidate for clinical intestinal implants.

Design of a force-measuring setup for colorectal compression anastomosis and first ex-vivo results

PurposeThe introduction of novel endoscopic instruments is essential to reduce trauma in visceral surgery. However, endoscopic device development is hampered by challenges in respecting the dimensional restrictions, due to the narrow access route, and by achieving adequate force transmission. As the overall goal of our research is the development of a patient adaptable, endoscopic anastomosis manipulator, biomechanical and size-related characterization of gastrointestinal organs are needed to determine technical requirements and thresholds to define functional design and load-compatible dimensioning of devices.MethodsWe built an experimental setup to measure colon tissue compression piercing forces. We tested 54 parameter sets, including variations of three tissue fixation configurations, three piercing body configurations (four, eight, twelve spikes) and insertion trajectories of constant velocities (5 mms−1, 10 mms−1,15 mms−1) and constant accelerations (5 mms−2, 10 mms−2, 15 mms−2) each in 5 samples. Furthermore, anatomical parameters (lumen diameter, tissue thickness) were recorded.ResultsThere was no statistically significant difference in insertion forces neither between the trajectory groups, nor for variation of tissue fixation configurations. However, we observed a statistically significant increase in insertion forces for increasing number of spikes. The maximum mean peak forces for four, eight and twelve spikes were 6.4 ± 1.5 N, 13.6 ± 1.4 N and 21.7 ± 5.8 N, respectively. The 5th percentile of specimen lumen diameters and pierced tissue thickness were 24.1 mm and 2.8 mm, and the 95th percentiles 40.1 mm and 4.8 mm, respectively.ConclusionThe setup enabled reliable biomechanical characterization of colon material, on the base of which design specifications for an endoscopic anastomosis device were derived. The axial implant closure unit must enable axial force transmission of at least 28 N (22 ± 6 N). Implant and applicator diameters must cover a range between 24 and 40 mm, and the implant gap, compressing anastomosed tissue, between 2 and 5 mm.

Toward stroke‐free coronary surgery: The role of the anaortic off‐pump bypass technique

Surgical coronary revascularization remains the preferred strategy in a significant portion of patients with coronary artery disease due to superior long-term outcomes. However, there is a significant risk of perioperative neurologic injury that has influenced guideline recommendations. These complications occur in 1%-5% of patients, ranging from overt neurologic deficits with permanent disability, to subtle cerebral defects noted on neuroimaging that may result in slow cognitive and functional decline. The primary mechanism by which these events occur is thromboembolism from manipulation of the ascending aorta. This occurs during cardiopulmonary bypass, aortic cross-clamping, and partial occlusion clamping (side clamp). Elderly patients and patients with aortic atheroma are, therefore, at significantly increased risk. Initial surgical techniques addressed this by aggressively debriding or replacing the ascending aorta during coronary artery bypass grafting (CABG). Strategies then moved toward minimizing aortic manipulation through pump-assisted beating heart surgery and off-pump surgery with partial occlusion clamping or proximal anastomosis devices. Finally, anaortic off-pump CABG aims to avoid all manipulation of the ascending aorta through advanced off-pump grafting techniques combined with in situ and composite grafts. This has been demonstrated to result in the greatest reduction in risk. Establishing successful anaortic off-pump CABG programs requires subspecialization and focused interest groups dedicated to advancing CABG outcomes.

The current state of bariatric endoscopy.

A variety of endoscopic bariatric and metabolic treatments (EBMTs) have been developed in recent years to combat the growing prevalence of obesity in the United States (US) and worldwide. This manuscript reviews the current state of bariatric endoscopy, detailing all US Food and Drug Administration (FDA) approved EBMTs including space-occupying intragastric balloons (IGBs), aspiration therapy, and endoscopic tissue apposition devices. Additionally, this review describes non-FDA approved treatments including additional IGBs, endoluminal bypass liners, duodenal mucosal resurfacing, and endoscopically placed anastomosis devices.

Compare outcome in patients of ileostomy and colostomy closure with surgical stapler versus ileostomy and colostomy closure with hand sewn anastomosis: a prospective study

Background: Diverting temporary stoma is created to protect the primary bowel pathology and distal anastomosis. Once that primary pathology has been overcome or distal anastomosis gets healed, closure of temporary stomas can be carried out. Invention of stapling devices for intestinal anastomosis provided another dimension than hand sewn method to the stoma closure techniques. In this study, we have compared two methods of loop stoma closure-hand sewn method versus stapler method.Methods: This is prospective comparative study in which 50 cases of loop ileostomy/colostomy were taken. 25 patients underwent ileostomy/colostomy closure by hand sewn anastomosis (group A). Another 25 patients underwent ileostomy/colostomy closure by stapler anastomosis (group B). Time taken for operation, initiation of oral intake, anastomotic leak, post-operative wound infection and total hospital stay duration were compared between these two groups to conclude about which method is superior and in the best interest of patient and surgeon.Results: Mean operation time 105.96 minutes (group A) and 72.84 minutes (group B). Mean time to start oral intake 5.36 days (group A), 3.6 days (group B). 16% patients (4/25) group A and 4% patients (1/25) group B developed anastomotic leak. 28% patients (7/25) group A and 8% patients (2/25) group B had post-operative wound infection. Mean hospital stay 10.4 days in group A and 7.84 days in group B.Conclusions: Stapler method provides significant benefits in terms of less operative time, early oral intake and less hospital stay. Overall stapler method for stoma closure is more efficient and cost effective.

Technical Development of the Sutureless ELANA Clip Anastomosis Device

Abstract A cranial bypass can be a last resort procedure for patients suffering from complex neurovascular pathology. Since the clinically proven excimer laser-assisted nonocclusive anastomosis (ELANA) technique has become available, it is no longer necessary to temporarily close the recipient artery to facilitate an anastomosis. Aiming to simplify and shorten the operation time of the ELANA technique, a sutureless ELANA, the so-called SELANA slide (SEsl) was developed, but it failed during clinical study. We developed an improved device, the SELANA clip (SEcl).We describe the SEcl design and the first in vitro test results. The SEsl design was optimized with a clip at the backside, creating the SEcl which facilitates smooth and friction-free insertion in the recipient artery. Subsequently, the laser catheter was optimized by adding a grid and conus to provide an improved vacuum and flat reaction surface during lasing. We aimed to compare the SEcl to the current ELANA regarding application time difference, anastomosis success (“flap retrieval”) and technical difficulties. Hereto 32 ELANA and 32 SEcl anastomoses were performed on pressurized rabbit arteries in the ELANA practice system. Mean application time difference was 14.0 min (95%CI 13.0–15.0). The flap retrieval rate of the ELANA anastomoses was 94% (30/32) and 100% (32/32) for the SEcl technique. During the experiments no technical difficulties were encountered. The SEcl is technical feasible with promising simplicity and application times. However, extensive in vivo short-term and long-term experiments are indispensable before clinical application.

New Absorbable Microvascular Anastomotic Devices Representing a Modified Sleeve Technique: Evaluation of Two Types of Source Material and Design

The purpose of this study was to create a new absorbable vascular anastomotic coupler and evaluate the patency and degradation degree. Vascular anastomosis was performed in the jugular vein in 31 New Zealand white female rabbits. The coupler consisted of an inner and outer ring. One side of the jugular vein was passed through and overlapped the inner ring. The opposite side of the jugular vein overlapped the everted jugular vein on the inner ring. Then, the outer ring engaged with the inner ring and completed the anastomosis. The outer rings were also constructed with two shapes including an O-type that had no slit and a C-type with a slit on the outer ring of the O-type coupler to allows expandability of the diameter. A Phase I experiment was performed to evaluate the degradability of the source materials, including the poly (lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) couplers. A Phase II experiment was performed to evaluate the patency and anastomosis time of the O-type PLGA and PCL couplers. A Phase III experiment was performed to evaluate the patency and anastomosis time of suture anastomosis (control) and the C-type PLGA coupler. The patency was determined by ultrasonography and open exploration. Histological analysis was performed to determine the degradability of the couplers. In Phase I, the PLGA couplers were completely degraded with good vascular wall remodeling at 8 months, while the PCL couplers demonstrated incomplete degradation. In Phases II and III, the anastomosis time was significantly shorter in the coupler groups than that in the control group. All of the coupler groups demonstrated complete patency of the anastomoses on ultrasonography. In Phase III, the C-type PLGA coupler also demonstrated patency and complete degradation at 8 months. PLGA is a suitable source material for absorbable couplers due to its fast degradability. We devised the O-shaped outer ring for the C-shaped outer ring to increase flexibility, which also demonstrated complete patency during the experimental period. Our absorbable microvascular anastomosis devices could provide rapid and reliable microvascular anastomosis without anastomotic failure.

Applying a clampless haemostatic device for left ventricular assist device outflow graft anastomosis.

Performing a left ventricular assist device outflow graft anastomosis in redo cases with a short ascending aorta and open vein grafts requires side clamping of the aorta and may necessitate temporary clamping of the vein grafts to optimize the surgical field. We aim to describe the technique and report our experience with applying the HeartString® device for the anastomosis of the left ventricular assist device outflow graft in 2 male patients with ischaemic cardiomyopathy following coronary artery bypass surgery. The feasibility of using the HeartString device has been shown and no procedure-related complication was documented.

Fabrication of a Novel Absorbable Vascular Anastomosis Device and Testing in a Pig Liver Transplantation Model.

An absorbable vascular anastomosis device (AVAD) was fabricated and tested in pig liver transplantation experiments. We prepared biodegradable copolymers with various ratios of L-lactide: glycolide and tested their properties including inherent viscosity, in vitro biodegradation, and tensile strength. The mechanical and physical properties of the finally selected copolymers were analyzed according to decomposition time. The AVAD, consisting of two inner rings and one coupler, was fabricated with 5-, 15-, and 20-mm diameter sizes using an injection molding machine. Based on changes in the overall mechanical and physical properties, it is believed that the AVAD will maintain its shape without deformation while connecting the blood vessels to external force for at least 3weeks. Four mini-pigs underwent liver transplantation with AVAD using livers obtained from swine leukocyte antigen-identical siblings. Anastomoses was achieved in all four cases. In case 4, an autopsy conducted at 4months revealed that the AVAD was absorbed and the anastomosis was intact, demonstrating the success of the AVAD in the pig liver transplantation experiments and the feasibility of using an AVAD in organ transplantation.

Short-term outcomes of surgical treatment of gastroesophageal junction cancer

To confirm simplicity, safety and efficacy of stapling devices for gastroesophageal anastomosis (including those formed in mediastinum) in the treatment of gastroesophageal junction cancer. There were 147 patients with cardioesophageal cancer. Tumors Siewert type II and III were predominant (44.2 and 40.3%, respectively). Simultaneous procedures were performed in 30.6% of cases. Postoperative complication rate was 42.2%. Pneumonia was the most common. Postoperative mortality was 2.7%.

Comparative model study of mechanical resistance of intestinal and stomach walls to the pressure in the device prototype for circular anastomosis

Background. The vital margins of the gut wall squee­zing, which is observed in cases of functional distension, negative pressure wound therapy or magnetic anastomosis device placing, ranged from 0.005 to 0.4 N/m2. The desirable short-time formation of structural connection in anastomotic line due to radio frequency electric influence, obviously, requires not vital, but a tight compression of the intestine wall on the verge of its structural deformation. C. Holmer et al. established the optimal value of electrode pressure onto the porcine intestine close to 1,125 mN/mm2. In our experiments, compression range of 2–6 · 104 N/m2 was found as more favorable for the radio frequency electric welding connection in anastomosis of the hollow organs. The purpose was to study the mechanical resistance of gut and stomach walls for comparative projection on its structural changes under strong pressure at the anastomosis model conditions. Materials and methods. The porcine intestine and stomach were delivered from the farm to laboratory during 6 hours in 4 оС and then heated in 0.9% NaCl up to 26–32 оС [6]. Two organ walls were placed inside the prototype device for human circular anastomosis, and then pressed for 60 seconds before radio frequency welding. The 117 probes were made in several combinations investigating pressure values 2.1, 3.0, 3.9 and 6.0 N/mm2 (or · 104 N/m2) effect for organ wall by connected micrometer device. Results. The wall thinning time, which is inversely proportional to resistance, visually divided into two phases: the fast (1–5 s) and significant thinning of the tissue after initial pressure application, then slow and low-amplitude thinning. The small intestine wall resistance was higher than the stomach one as well as the combination of the stomach and intestinal under all values of initial pressure. Conclusions. The first compression phase is unique according to the thinned organ. Some thinning rate decrease occurred at the second phase under the pressure 3.0–3.9 N/mm2 comparing to 2.1 N/mm2 up to 60 seconds, determines the limit of mechanical resistance of the wall muscle layer as well as overall gut and stomach integrity up to such pressure level. Obtained data helps to project the structural changes inside intestinal and/or stomach walls compressed into circular anastomotic device, which is important for the planning of further effects.

Comparison of venous couplers versus hand-sewn technique in free flap breast reconstruction

Despite positive outcomes reported in the literature, some surgeons remain reluctant to the systematic use of venous couplers in free flap tissue transfer. In our institution, the use of the coupler devices for venous anastomosis in free flap breast reconstruction has yet to be adopted by all surgeons. The purpose of the study was to compare postoperative outcomes of coupler-assisted venous anastomoses with hand-sewn techniques in free flap breast reconstruction. An analysis of collected data was performed on cases of breast reconstruction with free tissue transfer after mastectomy in breast cancer or BRCA-positive patients from 2010 to 2016. Patients were divided into two groups: coupler device and hand-sewn. The primary outcome was survival rate of free flaps. Secondary outcomes included potential complications, as well as surgical characteristics (recipient artery/vein, coupler size, type of hand-sewn anastomosis, size of sutures, number of venous anastomoses, ischemia time, operative time) RESULTS: We included 289 cases in our study. There were no significant differences between groups in terms of post-operative complications or survival rate of the free flaps. Ischemia time was significantly lower in both immediate and delayed reconstruction cases. Operative and anesthesia times were significantly lower only in immediate unilateral cases. Although ischemia time was reduced in the coupler group, we didn't find any significant difference in the operative and anesthesia time in the subgroup analysis, except for the group of immediate unilateral breast reconstruction. Couplers are safe and efficient; nevertheless, our study shows that their qualities cannot yet justify the disappearance of the manual sutures.

Hemodynamic performance of a sutureless anastomosis device (the Graft Connector): a numerical study.

Sutureless anastomosis devices have been developed to facilitate arterial bypass surgery on the beating heart. However, these devices can significantly alter the hemodynamics at the end-to-side anastomosis and in the host artery, leading to the formation of thrombus or/and intimal hyperplasia (IH). In this study, a numerical analysis was performed on the hemodynamic performance of the Graft Connector (GC), a sutureless anastomosis device, under pulsatile flow conditions. The results showed that blood flow was severely disturbed in the GC model with the formation of vortices and flow stagnation at the bed and the toe, and distal to each of the stent struts, which led to low wall shear stresses and high oscillating shear indices in these regions. This may cause severe IH in the host artery and compromise the performance of the device. Based on the numerical study, suggestions were proposed for the design of the GC to improve its performance.

Effect of Static Magnetic Fields on Proliferation and Apoptosis of Gallbladder Cancer Cells: An in vitro and in vivo study

Objectives: The knowledge on how static magnetic fields (SMF) of magnetic implants affect living cells and tissues is limited while these magnetic devices are more and more frequently adopted in certain surgical approaches. Methods: In this study, we exposed cultures of human gallbladder cancer cells to SMF continuously for up to 7 days, trying to simulate the exposure pattern of surgical magnetic implants, and implanted magnetic devices into tumor-bearing nude mice for 1 month, then evaluated the effect on proliferation and apoptosis of cancer cells and tissues. Results: It showed that after SMF exposure, whereas in vitro study showed decreased cell proliferation and increased apoptosis of the gallbladder cancer cells, in vivo study showed no significant differences both on proliferation and on apoptosis. Conclusions: Our findings indicate that with current magnetic biliary anastomosis devices, the SMF from magnetic implants shows little effects on proliferative and apoptotic activities of gallbladder cancer cells in vivo, while there are still possibilities that long-term continuous SMF exposure from surgical magnetic implants may interact with living cells, probably in a feeble manner.

The Pivotal Multicenter Trial of Ultrasound-Guided Percutaneous Arteriovenous Fistula Creation for Hemodialysis Access

PurposeTo evaluate safety and efficacy of arteriovenous fistulas (AVFs) created with a thermal resistance anastomosis device. Materials and MethodsA prospective single-arm trial at 5 sites enrolled 107 patients. Patients underwent ultrasound (US)-guided anastomosis creation between the proximal radial artery and perforating vein with the Ellipsys Vascular Access System (Avenu Medical, Inc, San Juan Capistrano, California) followed by separate maturation procedures. Primary endpoints were brachial artery flow volume ≥ 500 mL/min and target vein diameter ≥ 4 mm in > 49% of patients and absence of device-related complications at 90 days. ResultsAVFs with fused anastomoses were created in 95% (102/107) of patients. Maturation procedures included anastomotic balloon dilation in 72% (77/107), brachial vein embolization in 32% (34/107), cubital vein ligation in 31% (33/107), and surgical transposition in 26% (28/107) of patients. Primary flow and diameter endpoints were achieved in 86.0% (92/107) of patients, exceeding performance goal of 49% (P < .0001). No major adverse events were attributed to the device. Cumulative patency was 91.6%, 89.3%, and 86.7% at 90 days, 180 days, and 360 days. Target dialysis veins were cephalic, basilic, and brachial veins in 74% (73/99), 24% (24/99), and 2% (2/99) of patients. Two-needle dialysis was achieved in 88% (71/81) of patients on hemodialysis at a mean 114.3 days ± 66.2. Functional patency was 98.4%, 98.4%, and 92.3% at 90 days, 180 days, and 360 days. ConclusionsThe Ellipsys® Vascular Access System met primary safety and efficacy endpoint goals in the US pivotal trial.