Percutaneous intervention of a giant native coronary artery aneurysm using self-expanding stents.

In the absence of standardized management guidelines, coronary artery aneurysms (CAAs) present therapeutic challenges. Percutaneous coronary intervention (PCI) is rarely explored, especially in giant aneurysms with persistent angina, where surgery might be presumed as a preferred option. We describe the technical aspects and feasibility of PCI using Gore Viabahn expanded polytetrafluoroethylene (ePTFE)-covered nitinol self-expanding stents in a 66-year-old woman with a complex medical history and an enlarging, symptomatic right coronary artery aneurysm. The case was complicated by endoleak after the first stent, but intravascular ultrasound guidance enabled the precise deployment of additional stents, resulting in the successful exclusion of the aneurysm. This case demonstrates steps to successful CAA PCI with Gore Viabahn ePTFE-covered nitinol self-expanding stents and emphasizes that in unsuitable surgical candidates, PCI might be a potential alternative for symptomatic CAAs.

Custom-Made Implant Fabrication for Chin Augmentation Using Piled-Up Expanded Polytetrafluoroethylene Sheets: An Innovative Surgical Technique and Literature Review.

BACKGROUND: Alloplastic chin augmentation is the most common esthetic surgical treatment to reshape the chin. However, factory-made chin implants are typically standardized rather than custom-made and have potential to cause complications. Although the fabrication of custom-made implants by using computer-assisted planning and 3D-printing technology has become widespread, the process has several disadvantages, including long preoperative prosthesis preparation times, high costs, and unsuitability for patients with asymmetric chins or those who undergo combined mandibuloplasty before implant placement. The present study developed an innovative chin augmentation technique involving stacked expanded polytetrafluoroethylene (e-PTFE) sheets that is suitable for most patients and has minimal side effects. MATERIALS AND METHODS: A retrospective review of a single surgeon's experience was performed over a 2 year period for patients who underwent a procedure involving piled-up e-PTFE sheets for alloplastic chin augmentation. This study analyzed the outcomes, complications (temporary nerve numbness, wound infection, hematoma formation, and implant displacement), and patient satisfaction during follow-up. RESULTS: Between January 2018 and December 2020, 38 patients underwent the procedure involving piled-up e-PTFE sheets for alloplastic chin augmentation. Six patients (15.8%) experienced nerve-related temporary numbness, and one (2.6%) experienced wound infection. None had developed major complications such as implant displacement or wound infection at follow-up. Moreover, the patients demonstrated a high level of satisfaction with the surgical results. CONCLUSION: Piled-up e-PTFE sheets can be used to produce custom-fit porous polyethylene chin implants that result in minimal complications and a very high satisfaction rate. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Outcomes for expanded polytetrafluoroethylene strip in frontalis suspension surgery.

PURPOSE: This study evaluates surgical outcomes and complication rates of frontalis suspension with expanded polytetrafluoroethylene (ePTFE). METHODS: This retrospective cohort study reviewed all patients undergoing frontalis suspension surgery using ePTFE as the sling material from January 1 2012 to March 3 2020 by a single surgeon at a single academic center. Two different surgical techniques were evaluated in the placement of the sling material. Demographic, clinical, and operative data were extracted. Outcome data including postoperative lid height, reoperation, and complication rate were extracted for the cohort and compared between the two surgical techniques. Descriptive statistics were utilized. RESULTS: Sixty-four eyes from 49 unique patients were included in this study. Forty-three (67.2%) patients had isolated congenital blepharoptosis; 14 (21.9%) had blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES); and 2 (3.1%) had cranial nerve III palsy. Fifty-one (79.7%) patients had no prior blepharoptosis surgery. Lid crease incision and stab incision techniques were utilized for 24 (37.5%) and 40 (62.5%) eyes, respectively. Overall, 21 (32.8%) eyes required reoperation with ePTFE to achieve appropriate eyelid height or contour. Only one patient experienced implant infection, requiring removal of ePTFE sling after a second reoperation. There were no cases of implant exposure or granuloma formation noted during the study period. CONCLUSION: An ePTFE strip soaked in cefazolin prior to utilization in surgery is a viable material for frontalis suspension surgery, with a lower infectious or inflammatory complication rate than previously reported. However, reoperation rate was still relatively high.

Autologous saphenous vein and heparin-bonded expanded polytetrafluoroethylene as graft materials for below-the-knee femoro-popliteal bypass in patients with critical limb ischemia: A propensity score-matched analysis.

OBJECTIVE: To compare the outcomes of heparin bonded expanded polytetrafluoroethylene (HePTFE) and autologous saphenous vein (ASV) in patients undergoing below-knee (BK) femoro-popliteal bypass for critical limb ischemia (CLI). DESIGN: Retrospective single-centre matched case-control study. METHODS: From 2003 to 2019, 275 consecutive BK bypasses for CLI were performed, 109 with the ASV and 166 with a HePTFE graft. All the baseline characteristics that were reliably measured and were potentially relevant in the decision-making process were included as confounders in a logistic regression model and the factors that were significantly different between the two groups then used to perform a propensity matching analysis. Propensity score-based matching was performed in a 1:1 ratio to compare outcomes. Arterial hypertension, hyperlipemia, the need for tibial anastomosis at the distal level and the run-off status were the covariates included in the matching. Follow-up outcomes were estimated by Kaplan-Meier methods and compared with log rank test. RESULTS: After propensity matching, 101 HePTFE bypasses were matched with 101 ASV bypasses. The median duration of follow-up was 37 months (range 1-192). The 5-year survival rate was 67.5% (standard error (SE) 0.05) in the HePTFe group and 64.5% (SE 0.06) in the ASV group (p = 0.8, log rank 0.04). Primary patency rates were 38% (SE 0.06) in the HePTFE group and 41% (SE 0.06) in the ASV group (p = 0.7, log rank 0.3). Also assisted primary patency and secondary patency rates did not differ in the two groups. Amputation-free survival was 53% (SE 0.05) in the HePTFE group and 58% (SE 0.06) in the ASF group (p = 0.6, log rank 0.2). CONCLUSIONS: HePTFE provided 5-year similar results to those obtained with use of the ASV in equivalent patients with CLI undergoing below-knee or tibial bypass.

Bacterial adherence to silk and expanded polytatrafluorethilene sutures: an in vivo human study.

After oral surgery, bacterial adhesion to suture can cause surgical site infections and delay wound healing. Microbial adherence to the suture is influenced by its physical configuration and chemical structure. The aim of this study was to compare in vivo the bacterial adhesion to two suture materials used in oral surgery: silk and monofilament expanded polytetrafluoethilene (e-PTFE). After sinus lift surgery, 15 flaps were sutured with silk (nonabsorbable, organic, braided, 4.0) and 15 were sutured with e-PTFE (nonabsorbable, synthetic, monofilament, 4.0). Seven days after surgery, bacterial adherence, in terms of percentage of the surface covered, was evaluated for each suture material by scanning electron microscope (SEM). Onto silk suture, plaque consisted of a few cocci and a higher proportion of rods and filamentous-shaped bacteria, with some mineralized plaque. Onto e-PTFE speciments, only small colonies of a few cocci or no bacteria were observed, with empty spaces between the colonies and no plaque mineralization. The surface covered by bacteria on e-PTFE specimens was significantly lower than that of silk sutures. (22.1% ±4.96% vs 54.3% ± 7.9%; P =0.0001). The results of the present study suggest that multifilament structure of silk favours a greater bacterial adherence, proliferation, and persistence, so monofilament and e- PTFE suture should be preferred in oral surgery.

Viscosity characterization and flow simulation and visualization of polytetrafluoroethylene paste extrusion using a green and biofriendly lubricant.

Polytetrafluoroethylene (PTFE) and expanded PTFE (ePTFE) are ideal for various applications. Because PTFE does not flow, even when heated above its melting point, PTFE components are fabricated using a process called paste extrusion. This process entails blending PTFE powder particles with a lubricant to form PTFE paste, which is subsequently preformed, extruded, expanded (in the case of ePTFE), and sintered. In this study, ethanol was proposed as an alternative green lubricant for PTFE processing. Not only is ethanol benign and biofriendly, it provides excellent wettability and processing benefits. Using ethanol as a lubricant, the shear viscosity of PTFE paste and its flow behavior during paste extrusion were investigated. Frequency sweeps using a parallel-plate rheometer were performed on PTFE paste samples and various grits of sandpaper were used to reduce wall slip of PTFE paste. A viscosity model was generated and a multiphysics software was used to simulate PTFE paste extrusion. The simulated extrusion pressure was compared to experimental data of actual paste extrusion. Flow visualization experiments using colored PTFE layers were conducted to reveal the flow profile of the PTFE paste. The morphology of the expanded ePTFE tubes was examined using scanning electron microscopy and the effect of expansion ratio on ePTFE morphology was quantified.

Frequency of perigraft hygroma after open aortic reconstruction.

OBJECTIVE: The incidence of perigraft hygroma (PGH) development after aortic reconstruction remains poorly defined and its clinical relevance is questionable. This study was designed to establish the incidence of and determine the risk factors associated with PGH formation and its outcomes. METHODS: Patients who underwent open aortic reconstruction for either aneurysmal or occlusive disease with an expanded polytetrafluoroethylene (ePTFE) or polyester graft from 2004 to 2018 were retrospectively reviewed (n = 262). Only those who had follow-up imaging 3 or more months after repair were included. Patients with mixed graft types were excluded. PGH was defined as a perigraft fluid collection of 30 mm or greater in diameter with a radiodensity of 30 or fewer Hounsfield units on computed tomography at a minimum of 3 postoperative months. Analysis was conducted between patients with and without PGH. RESULTS: One hundred forty patients met the inclusion criteria: 88 were treated with ePTFE and 52 with polyester grafts. Twenty-three patients (16.4%) were found to have radiologic evidence of PGH. PGH developed more frequently in patients with ePTFE (21/88 [23.9%]) compared with those with polyester grafts (2/52 [3.8%]) (P = .002). Mean PGH size was 63.5 ± 36.4 mm (range, 33-153 mm) and the average time to PGH detection 27.7 months (range, 3-112 months). Baseline characteristics were similar between the groups. Patients who developed PGH had larger aneurysms, more often received ePTFE grafts, had larger graft diameters, and had bifurcated grafts. The overall mortality was 32.1% at a mean follow-up of 5.2 years. The 5-year mortality rates were similar between patients with and without PGH (26.1% vs 18.8%; P = .41). Of the 23 patients with PGH, 4 (all with ePTFE) presented with symptoms related to the PGH. The average size of symptomatic and asymptomatic PGH were 11.5 and 4.8 cm, respectively. Mortality rates overall were similar between those with and without symptoms (50.0% vs 36.8%; P = .99). CONCLUSIONS: Nearly one-quarter of aortic reconstructions with ePTFE are associated with PGH formation compared with 4% with polyester. Clinically significant PGH-related symptom development occurs in 20%. Patient education and close surveillance are warranted. Manufacturer's device modification is needed.

Prevalence and risk factors for heparin-bonded expanded polytetrafluoroethylene vascular graft infection after infrainguinal femoropopliteal bypasses.

BACKGROUND: To analyze the prevalence and predictors of prosthetic vascular graft infection (PVGI) in a multicenter registry. METHODS: This registry-based, multicenter study retrospectively evaluated PVGI that developed after infrainguinal revascularization performed with a heparin-bonded expanded polytetrafluoroethylene graft that was used in 1400 interventions between 2002 and 2016. A prosthetic graft with infection was defined as direct involvement of the graft with positive bacterial cultures of graft or perigraft material, intraoperative gross purulence or failure of graft incorporation, or exposed graft in an infected wound. RESULTS: Critical limb ischemia (CLI) was the main indication for bypass (n = 915 [65%]). The median duration of follow-up was 29 months (range, 1-168 months; interquartile range, 12-60 months). A total of 33 heparin-bonded expanded polytetrafluoroethylene grafts (2.3%) became infected; the median time to occurrence was 5 months (range, 1-54 months; interquartile range; 2.00-13.25 months). Freedom from PVGI at 1 year was 98% (standard error, 0.4; 95% confidence interval [CI], 97.2-98.9), and 97% (standard error, 0.6; 95% CI, 95.6-98.0) at 5 years. The multivariate model identified CLI (P = .042; hazard ratio, 0.39; 95% CI, 0.164-0.969) to be independently associated with PVGI. In-hospital mortality of PVGI treatment was 12% (n = 4/33). Freedom from major amputation was significantly different between patients with PVGI and those who did not experience this complication (at 1 year, 67.0% vs 88.5%; Log-rank χ2 = 22.5; P = .001). CONCLUSIONS: In our "real-world" multicenter experience the prevalence of PVGI after infrainguinal femoropopliteal bypasses was relatively low at 2.3%, but still associated with significant mortality and limb loss. CLI was the only significant predictor of PVGI. This conclusion is reasonable; however, more comprehensive data are required to confirm these findings, because the presence of ischemic ulcers or gangrene was not predictive of PVGI.

Autologous Vascularization: A Method to Enhance the Antibacterial Adhesion Properties of ePTFE.

BACKGROUND: Expanded polytetrafluoroethylene (ePTFE), an ideal bioimplant material, is commonly used in surgical repair to treat soft tissue defects and deformities. However, the main disadvantage of ePTFE is that its distinctive porous ultrastructure is prone to bacterial adhesion that gives rise to infection and chronic inflammation, resulting in functional failure. Herein, a potentially promising approach to ePTFE autologous vascularization (AV-ePTFE) in vivo was established and developed to enhance the material's antibacterial properties. METHODS: Hematoxylin and eosin (H&E) staining and visual observation were performed to validate the intensity of the inflammatory response and related histological changes in surgical wounds after AV-ePTFE implantation. In addition, the antibacterial activities of AV-ePTFE were assessed by an in vitro bacterial adhesion assay and scanning electron microscope observation. RESULTS: The optimal time point of AV-ePTFE was 12 weeks after implantation. AV-ePTFE relieved inflammation based on an inflammation grading evaluation and expedited wound healing. Furthermore, AV-ePTFE effectively reduced the number of bacterial adhesions, inhibited bacterial biofilm formation, and prevented the occurrence of infection. CONCLUSIONS: We conclude that autologous vascularization is an effective method to improve the antibacterial adhesion properties and biocompatibility of ePTFE after implantation and that it may have a significant effect on clinical application of future porous biomaterials.

Surgical outcome of pulmonary artery reconstruction using the expanded polytetrafluoroethylene patch in patients with lung cancer.

PURPOSE: Pulmonary artery reconstruction is sometimes utilized as an alternative to pneumonectomy in lung cancer surgery. We herein report our experience of pulmonary artery reconstruction using an expanded polytetrafluoroethylene (ePTFE) patch based on the surgical results and long-term outcome. METHODS: Clinical records of lung cancer patients who underwent patch plasty were reviewed retrospectively. RESULTS: Between 2003 and 2017, pulmonary artery patch plasty were performed in 21 patients [18 males, 3 females; mean age 65 (range 47-79) years]. Induction chemoradiotherapy was performed in three patients. Bronchoplasty was performed in five patients. The pathologic stages were stage I in 3 patients, stage II in 6 and stage III in 12. Pneumonectomy, lobectomy and segmentectomy were performed in 2, 18 and 1 patient, respectively. The left upper lobe was the most frequent origin of lung cancer (15 patients). There was no reconstruction-related morbidity or mortality. The overall survival rate at 5 years was 64.1% with a mean follow-up of 39.5 months, and the survival rates for N0-1 and N2-3 were 80.8% and 28.6%, respectively. CONCLUSION: Patch angioplasty using the ePTFE sheet is a reliable procedure in radical surgery for lung cancer.

Fabrication and Characterization of MSQ Aerogel Coating on ePTFE Thin Films for Cable Sheaths.

With methylsilsesquioxane (MSQ) aerogels synthesized by the sol-gel method as a raw material and Si-Ti sol as a binder, an alcohol-based aerogel slurry consisting of only MSQ aerogel and Si-Ti sol was prepared and coated on expanded polytetrafluoroethylene (ePTFE) to form an MSQ aerogel coating layer, followed by low-temperature heat treatment. The effect of Si-Ti sol content on the microstructure of the MSQ aerogel coating layer was investigated, and the properties of a typical MSQ aerogel-layer-coated ePTFE film were evaluated. The results show that Si-Ti sol has an important role in terms of film-forming capability, surface smoothness, flexibility, and powder dropping of the MSQ aerogel coating layer. With a Si-Ti sol of 10.5 wt.% content as a binder and after heat treatment at 170 °C for 30 min, the coated ePTFE flexible thin film with a layer thickness of 30 µm shows high uniformity, integrity, and electrical insulation properties, with an elongation at break decrease over 130%, a thermal conductivity of 0.1753 W/(m·K) at 25 °C, a dielectric constant of 16.5674, and a dielectric loss of 0.06369, which can be promisingly applied in cable sheaths.

Design of in situ porcine closed-circuit system for assessing blood-contacting biomaterials.

The overall pre-clinical process of determining the blood compatibility of any medical device involves several stages. Although the primary purpose is to protect the patients, laboratory testing has been over-utilized for many years with a huge number of unnecessary animal tests being done routinely. Recently, the elimination of needless testing has become important in controlling the cost of healthcare and in addressing many issues related to the ethics of animal research. With this in mind, we designed a new in situ porcine closed-circuit system to study the complex interplay between platelets, coagulation proteins, and other cellular elements in pigs. We proved that this system can be implemented in blood compatibility testing and minimize the number of animals used in the experiments.

Late results of right ventricular outflow tract reconstruction with a bicuspid expanded polytetrafluoroethylene valved conduit.

BACKGROUND AND AIM TO READ: We report the results of a bicuspid expanded polytetrafluoroethylene (ePTFE) valved conduit used for right ventricular outflow tract reconstruction (RVOTR). METHODS: Between November 2005 and February 2009, 12 conduits were used for RVOTR. The mean age and weight of patients were 43.5 ± 46.4 months and 13.4 ± 8.6 kg. The main diagnosis was tetralogy of Fallot with pulmonary atresia in eight patients. The most common conduit size was 18 mm. The mean follow-up was 88.0 ± 35.9 months. RESULTS: There were no operative and late mortalities. At discharge, the mean peak systolic pressure gradient across the RVOT was 14.1 ± 11.3 mmHg. There was no conduit valve regurgitation in nine patients. At the latest echocardiography (mean follow-up: 84.3 ± 35.5 months), the mean peak systolic pressure gradient across the RVOT was 59.7 ± 20.2 mmHg, and there was no conduit valve regurgitation in six patients. Freedom from conduit malfunction was 100% and 83.3%, at 1 and 8 years, respectively. Two conduits were explanted due to sternal compression and four from conduit malfunction. Freedom from explantation was 83.3% and 74.2% at 2 and 8 years, respectively. CONCLUSIONS: ePTFE bicuspid valved conduit has good late function in terms of valve regurgitation, but the pressure gradient across the conduit increases with time, which is the main cause of conduit failure and explantation.

Behavior of a new long-chain cyanoacrylate tissue adhesive used for mesh fixation in hernia repair.

BACKGROUND: Synthetic tissue adhesives (TA) are sometimes used in hernia repair surgery. This study compares the use of a new, noncommercial, long-chain cyanoacrylate (n-octyl) TA and Ifabond for mesh fixation. MATERIALS AND METHODS: In two implant models in the rabbit, expanded polytetrafluorethylene meshes were fixed to the parietal peritoneum using a TA or tacks (intraperitoneal model), or polypropylene meshes used to repair partial abdominal wall defects were fixed with a TA or sutures (extraperitoneal model). Animals were euthanized 14 or 90 d postsurgery and implant specimens were processed for microscopy (labeling of macrophages and apoptotic cells), peritoneal fluid and biomechanical strength testing. Interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were determinated in peritoneal fluid. RESULTS: Mesothelial cell deposition on the intraperitoneal implants fixed using the new TA and Ifabond was adequate and similar IL-6 and TNF-α levels were detected in these implants. Intraperitoneal meshes fixed with tacks showed IL-6 overexpression. Three months after surgery, macrophage and apoptotic cell rates were higher for the intraperitoneal implants fixed with Ifabond versus the new TA or tacks. In the extraperitoneal model, reduced macrophage and cell damage responses were observed in the meshes fixed with sutures versus both TA. Tensile strengths were greater for the tacks versus TA in the intraperitoneal implants and similar for the sutures and TA in the extraperitoneal implants (90 d). CONCLUSIONS: Both TA showed a good cell response in both models. Their use in an intraperitoneal location resulted in reduced tensile strength compared with the tacks. However, strengths were comparable when extraperitoneal implants were fixed with these adhesives or sutures.

Angioscopic and optical coherence tomographic evaluation of neointimal coverage: 9 months after expandable polyterafluoroethylene covered stent implantation.

An expandable polytetrafluoroethylene (ePTFE) covered stent is generally employed to seal coronary artery perforation. The frequency of ePTFE covered stent use is relatively low; thus, only a handful of studies have reported neointimal coverage and endothelialization inside the deployed ePTFE and clinical time course after ePTFE implantation. This case report presents a 78-year-old man treated with an ePTFE covered stent when he suffered from coronary artery perforation after the implantation of two everolimus eluting stents in the left anterior descending artery. Follow-up coronary angiography 9 months after ePTFE covered stent implantation depicted favorable stent patency. Optical coherence tomography showed thin and uneven stent strut coverage at the culprit. Angioscopy also depicted partial white-coated coverage and stent strut exposure. The outcome of this case suggested that long-term dual antiplatelet therapy should be prescribed for preventing thrombosis after ePTFE covered stent implantation.

Nursing Care for Patients with Synthetic Arteriovenous Grafts.

Dealing with a growing older adult patient population, keeping pace with current guidelines, and adhering to new recommendations is a perpetual endeavor for healthcare professionals. Because determining the best access for individual patients is not always obvious, vascular access is a challenging aspect of patient care. This article presents information on the ever-evolving and improving world of vascular access, specifically synthetic grafts.

Parastomal hernia repair with the Sugarbaker technique using e-PTFE mesh.

PURPOSES: Although surgery is commonly used to treat parastomal hernia, it is very difficult and has shown poor results. Recently, repair with prosthetic materials has been thought to be a more promising method. METHODS: The Sugarbaker technique with e-PTFE mesh (Dualmesh®) performed via open surgery was adopted for seven patients with parastomal hernia. Two of them were recurrent cases. Three of the patients experienced incarceration of the intestine and recovered conservatively before surgery. The median age of the patients at the parastomal hernia repair was 77.6 years old (range 37.7-84.7). RESULTS: The median operative time was 211 min (range 147-256). The median hernia size was 28 cm2 (range 7.5-60 cm2). The median amount of blood loss during the operation was 158 g (range 0-370 g). Surgical site infection was not observed. The postoperative median hospital stay was 17 days (range 13-40) and the median follow-up was 2.4 years (range 1.0-3.7). During the follow-up period, we did not observe recurrence or readmission. CONCLUSIONS: The surgical results were satisfactory with minimal morbidity and no recurrences. The Sugarbaker technique for parastomal repair using e-PTFE mesh may be suitable as a standard method for treating parastomal hernia.

TIPS for refractory ascites: a 6-year single-center experience with expanded polytetrafluoroethylene-covered stent-grafts.

OBJECTIVE. This single-center study evaluated the use of expanded polytetrafluoroethylene (ePTFE)-covered stent-grafts for transjugular intrahepatic portosystemic shunt (TIPS) placement to manage portal hypertension-related refractory ascites. MATERIALS AND METHODS. One hundred patients at a single tertiary care center in a major metropolitan hospital underwent TIPS placement with an ePTFE-covered stent-graft (Viatorr TIPS Endoprosthesis). Patients with portal hypertension-related ascites and preexisting hepatocellular carcinoma or liver transplant were excluded from the analysis. Records were reviewed for demographic characteristics, technical success of the TIPS procedures, and stent follow-up findings. Clinical results were assessed at 90- and 180-day intervals. RESULTS. Immediate technical success of the TIPS procedure was 100%. Of the 61 patients with documented follow-up, 55 (90.2%) had a partial or complete ascites response to TIPS creation. Of these 55 patients, nine experienced severe encephalopathy. Six of 61 patients (9.8%) did not experience a significant ascites response. Overall survival was 78.7% at 365-day follow-up. The 365-day survival was 84.2% for patients with a model for end-stage liver disease (MELD) score of less than 15, 67.0% for those with a score of 15-18, and 53.8% for those with a score of greater than 18 (p = 0.01). For patients with a MELD score of less than 18, the 365-day survival was 88.0% for those with an albumin value of 3 mg/dL or greater and 72.8% for those with an albumin value of less than 3 mg/dL (p = 0.04). CONCLUSION. TIPS placement using an ePTFE-covered stent-graft is an efficacious therapy for refractory ascites. Patients with preserved liver function-characterized by a MELD score of less than 15 or a MELD score of less than 18 and an albumin value of 3 mg/dL or greater-experience the greatest survival benefit.

Evaluating patency rates of an ultralow-porosity expanded polytetrafluoroethylene covered stent in the treatment of venous stenosis in arteriovenous dialysis circuits.

PURPOSE: To evaluate the efficacy of an ultralow-porosity expanded polytetrafluoroethylene (ePTFE) covered stent in the treatment of autogenous arteriovenous fistula (AVF) and prosthetic arteriovenous graft (AVG) venous outflow stenoses. MATERIALS AND METHODS: Clinical and angiographic outcomes of 20 consecutive patients with arteriovenous dialysis circuits treated with the endoprosthesis were reviewed following institutional review board approval. Patients were followed routinely at 2 months and 6 months after stent placement, or earlier if clinically warranted. The primary endpoint was 2- and 6-month primary treatment area patency. Secondary endpoints included primary circuit patency, primary assisted patency, and secondary patency. RESULTS: Eleven patients with AVFs and nine patients with AVGs were treated successfully with the covered stent. Primary treatment area patency rates were 85% ± 16 at both 2 months and 6 months. Primary circuit patency rates were was 65% ± 21 and 45% ± 22, respectively; primary assisted patency rates were 90% ± 13 and 85% ± 16, respectively; and secondary patency rates were 100% and 90% ± 13, respectively. Of the three cases of lost primary treatment area patency, two developed thrombosis and one developed recurrent stenosis. No significant differences were found between patients with AVFs and AVGs. CONCLUSIONS: Data from this preliminary study suggests that the ultralow-porosity ePTFE covered stent may be a clinically viable option for treatment of venous outflow stenoses in arteriovenous vascular access circuits.

Expanded Polytetrafluoroethylene Mesh in Chest-wall Reconstruction: A 27-year Experience.

OBJECTIVES: To evaluate the success of expanded polytetrafluoroethylene (ePTFE) mesh in chest-wall reconstruction. METHODS: We retrospectively reviewed patients who underwent ePTFE (Gore-Tex®) chest-wall reconstruction. The main outcome was a mesh-related event, defined as a mesh-related reoperation (e.g., mesh infection requiring debridement with/without explant, tumor recurrence with explant) and/or structural dehiscence/mesh loosening with/without a hernia. Demographics and surgical outcomes were reported. RESULTS: 246 reconstructions met inclusion (1994-2021). Fifty-five (22.4%) reconstructions had mesh-related events within a median of 1.08 years (IQR 0.08, 4.53) postoperatively; those without had a stable chest for a median of 3.9 years (IQR, 1.59, 8.23, p<0.001). Forty-one (16.6%) of meshes became infected, requiring reoperation. Eighty-eight percent (36/41) were completely explanted; 8.3% (3/36) required additional mesh placement. Predictors of mesh-related events were prior chest-wall radiation (OR=9.73, CI 3.47 to 30.10, p<0.001), higher BMI (OR 1.08, CI 1.01 to 1.16, p=0.019), and larger defects (OR 1.48, CI 1.02 to 2.17, p=0.042). The risk of mesh-related events with obesity was higher with prior chest-wall radiation. CONCLUSIONS: Most (78%) patients with an ePTFE mesh had a stable reconstruction after a median of 4 years. Obesity, larger defects, and prior chest-wall radiation were associated with a higher risk of a mesh-related event mostly due to mesh infections. Seventeen percent of reconstructions had reoperation for mesh infection; 88% were completely explanted. Only 8% required replacement mesh, suggesting that experienced surgeons can safely manage them without replacement. Future studies should compare various meshes for high-risk patients to help guide the optimal mesh selection.