Vascular Devices Research Articles

The selection of the suitable long peripheral catheter in DIVA patients: The significance of ultrasonography.

There are several types of LPC (long peripheral catheters) that vary in length, size, insertion method, and cost. The aim of the study was to evaluate whether ultrasonography can be useful for the selection of the suitable LPC in DIVA (difficult intravenous access) patients. Based on the ultrasonographic examination, a long peripheral catheter was selected. A 6.4 cm LPC into a vein at a depth of up to 0.5 cm, a 8.5 cm LPC into a vein at a depth up to 1.5 cm, and a 9.8 cm catheter at a depth up to 2 cm using the cannula over needle method. A 12 cm catheter was inserted into the deeper veins using the direct Seldinger method. The catheter diameter was no more than 33% vein diameter. Dwell time and the number of complications of four vascular devices were recorded and compared. One thousand one hundred fifty-six patients, average age 76 years (19-102), 501 men and 655 women, were included in the study. Average dwelling time was 10 days (1-30), there were 136 complications (11.7%). A catheter 6.4 cm long was inserted in 346 (29.8%), 8.5 cm in 140 (12.1%), 9.8 cm in 320 (27, 5%), and 12 cm in 356 (30.6%) patients. There were no significant differences in dwelling time, rate, and type of complications among the four catheters used. Our results confirm that ultrasound examination can be useful for the selection of the suitable long peripheral catheter in DIVA patients.

How often are infusion sets for central venous catheters changed in Australian and New Zealand Intensive Care Units? A point prevalence survey

BackgroundInfusion sets (comprising the tubing, measuring burettes, fluid containers, transducers) that are connected to invasive vascular devices are changed on a regular basis in an effort to reduce bacterial colonisation and bloodstream infection. There is a balance between reducing infection and creating unnecessary waste. Current evidence suggests that for central venous catheters (CVCs), changing infusion sets at 7 days does not increase infection risks. ObjectivesThe objective of this study was to describe the current unit guidelines in Australian and New Zealand intensive care units (ICUs) for changing infusion sets for CVCs. Methodsprospective cross-sectional point prevalence study, as a part of the 2021 Australian and New Zealand Intensive Care Society Point Prevalence Program. ParticipantsAustralia and New Zealand (ANZ) adult ICUs and their patients on the day of the study. ResultsData were collected from 51 ICUs across ANZ. One-third of these (16/49) ICUs had a guideline that specified a 7-day replacement period, with the rest having a more frequent replacement period. ConclusionMost ICUs participating in this survey had policies to change their CVC infusion tubing in 3–4 days, and recent high-level evidence supports an update to extend this to 7 days. There remains work to be done to spread this evidence to ANZ ICUs and improve environmental sustainability initiatives.

A bio-instructive parylene-based conformal coating suppresses thrombosis and intimal hyperplasia of implantable vascular devices

Implantable vascular devices are widely used in clinical treatments for various vascular diseases. However, current approved clinical implantable vascular devices generally have high failure rates primarily due to their surface lacking inherent functional endothelium. Here, inspired by the pathological mechanisms of vascular device failure and physiological functions of native endothelium, we developed a new generation of bioactive parylene (poly(p-xylylene))-based conformal coating to address these challenges of the vascular devices. This coating used a polyethylene glycol (PEG) linker to introduce an endothelial progenitor cell (EPC) specific binding ligand LXW7 (cGRGDdvc) onto the vascular devices for preventing platelet adhesion and selectively capturing endogenous EPCs. Also, we confirmed the long-term stability and function of this coating in human serum. Using two vascular disease-related large animal models, a porcine carotid artery interposition model and a porcine carotid artery-jugular vein arteriovenous graft model, we demonstrated that this coating enabled rapid generation of self-renewable “living” endothelium on the blood contacting surface of the expanded polytetrafluoroethylene (ePTFE) grafts after implantation. We expect this easy-to-apply conformal coating will present a promising avenue to engineer surface properties of “off-the-shelf” implantable vascular devices for long-lasting performance in the clinical settings.

Peripherally inserted central catheter insertion and management in Hodgkin and non-Hodgkin lymphomas: a 13-year monocentric experience

BackgroundNon-Hodgkin’s lymphoma (NHL) and Hodgkin’s lymphoma (HL) are two of the most common hematologic diseases that require an infusion of immunochemotherapies in conjunction with radiotherapy, often in an outpatient setting. For relapsed/refractory disease, autologous peripheral hematopoietic stem cell transplantation and sometimes allogeneic transplantation (HSCT) are considered standard treatment options. Recently, chimeric antigen receptor (CAR) T cells and bispecific antibodies have emerged as an important and effective option for the treatment of relapsed/refractory patients. These medical approaches deserve effective, safe, and durable vascular access, especially for the ambulatory population undergoing discontinuous treatment associated with high rates of complications and life-threatening toxicities. Peripherally inserted central catheters (PICCs) are vascular devices with an intermediate-to-long-term lifespan that are inserted ultrasonically into a peripheral brachial vein. Their ease of insertion by trained nurses and low rate of catheter-related infectious and thrombotic complications make them ideal devices for treating oncology and hematology patients.PurposeIn this study, we aim to demonstrate that PICCs are an essential tool for the treatment of HL and NHL patients in terms of efficiency and safetyMethods and resultsFrom March 2007 to June 2020, 316 PICC implantations were performed by our PICC team in 276 HL patients and 363 PICC in 322 NHL patients. The total lifespan of the PICCs was 50,660 days in HL and 43,919 days in NHL patients. Most PICCs were removed at the end of therapy, and the rate of mechanical complications was low. Only one and four episodes of confirmed PICC-related catheter-related bloodstream infections (CRBSIs) (0.3%; 0.02/1,000 days/PICC and 1.2%; 0.07/1,000 days/PICC) were recorded in HL and NHL patients, respectively. There were only 11 (3.6%; 0.25/1,000 days/PICC) and nine (2.6%; 0.17/1,000 days/PICC) episodes of symptomatic PICC-related thrombotic complications in HL and NHL patients, respectively, without removal.ConclusionOur data indicate that the PICC can be considered the device of choice for treating HL and NHL patients because it is easy to insert, safe to use, long-lasting, and has a low complication rate, especially in the outpatient setting.

Fully Endoscopic Mitral Valve Repair with Percutaneous Cannulation of Groin Vessels.

Endoscopic mitral valve surgery (EMS) has become a standard of care at specialized heart centers, further reducing surgical trauma compared to a traditional minimally invasive, thoracotomy-based approach. Exposure of the groin vessels for the establishment of cardiopulmonary bypass (CPB) via surgical cutdown in minimally invasive surgery (MIS) may result in wound healing disorders or seroma formation. The avoidance of surgical exposure of the groin vessels by using fully percutaneous techniques for the insertion of a CPB cannula with the implementation of vascular pre-closure devices has the potential to reduce these complications and improve clinical results. Herein, we present the utilization of a novel plug based vacsular closure device with a resobable collagen plug and the absence of suture material for closure of the arterial access for CPB in MIS. While this device was initially predominantly used in transcatheter aortic valve implantation (TAVI) procedures, with its safety and feasibility shown, we herein show that it can be used in CPB cannulation, since it is capable of closing arterial access sites up to 25 French (Fr.) in size. This device may be suitable to significantly reduce groin complications in MIS and simplify the establishment of CPB. Here, we describe the fundamental steps of EMS, including percutaneous groin cannulation and decannulation using a vascular closure device.

Vascular Surgery Innovation Over Three Decades: An Analysis of Food and Drug Administration Device Approvals

Vascular surgery has undergone rapid changes, delivering improvements in patient outcomes. Much of this improvement has been catalyzed by the availability of new technology. We aim to evaluate the areas of past and ongoing innovation by analyzing all vascular device Food and Drug Administration (FDA) applications. We retrospectively compiled device approval applications submitted to the FDA Circulatory System Devices Advisory Panel since inception in 1963 (N = 134,037), including both Pre-Market Approval (PMA) and 510(k) applications. PMA applications, which typically require human trials before the approval of novel devices, were considered to represent a greater degree of innovation compared with 510(k)s, which are largely based on similarity to previously approved devices. Between 1995 and 2012, vascular applications grew rapidly, increasing over 140% during this time period (Fig 1); however, applications for vascular devices have fallen since 2012 by over 10%. The portion of these applications representing PMAs has increased steadily and remains statistically significantly higher than other procedural specialties (Fig 2). The categories with the greatest change in applications between 2010 and 2020 include embolectomy catheters (−71%, P < .001), guide catheters (−30%, P = .02), access devices (49%, P = .01), angioplasty catheters (156%, P < .001), visceral stents (248%, P < .001), and peripheral stents (61.8%, P < .001). Although we are limited in the degree to which we can evaluate their impact or novelty, applications for vascular device approval suggest that the burst of innovation following the beginning of the endovascular era has plateaued. More recent applications have focused on well-established categories and are increasingly sponsored by a small number of large corporations. Society and federal policies should aim to sustain the pace, quality, and diversity of innovation in vascular surgery.Fig 2PMAs as percentages of applications.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Continuous extracorporeal femoral perfusion model for intravascular ultrasound, computed tomography and digital subtraction angiography.

We developed a novel human cadaveric perfusion model with continuous extracorporeal femoral perfusion suitable for performing intra-individual comparison studies, training of interventional procedures and preclinical testing of endovascular devices. Objective of this study was to introduce the techniques and evaluate the feasibility for realistic computed tomography angiography (CTA), digital subtraction angiography (DSA) including vascular interventions, and intravascular ultrasound (IVUS). The establishment of the extracorporeal perfusion was attempted using one formalin-fixed and five fresh-frozen human cadavers. In all specimens, the common femoral and popliteal arteries were prepared, introducer sheaths inserted, and perfusion established by a peristaltic pump. Subsequently, we performed CTA and bilateral DSA in five cadavers and IVUS on both legs of four donors. Examination time without unintentional interruption was measured both with and without non-contrast planning CT. Percutaneous transluminal angioplasty and stenting was performed by two interventional radiologists on nine extremities (five donors) using a broad spectrum of different intravascular devices. The perfusion of the upper leg arteries was successfully established in all fresh-frozen but not in the formalin-fixed cadaver. The experimental setup generated a stable circulation in each procedure (ten upper legs) for a period of more than six hours. Images acquired with CT, DSA and IVUS offered a realistic impression and enabled the sufficient visualization of all examined vessel segments. Arterial cannulating, percutaneous transluminal angioplasty as well as stent deployment were feasible in a way that is comparable to a vascular intervention in vivo. The perfusion model allowed for introduction and testing of previously not used devices. The continuous femoral perfusion model can be established with moderate effort, works stable, and is utilizable for medical imaging of the peripheral arterial system using CTA, DSA and IVUS. Therefore, it appears suitable for research studies, developing skills in interventional procedures and testing of new or unfamiliar vascular devices.

Shape memory polymer technology in peripheral vascular embolization.

Porous, radiolucent, shape memory polymer is a new technology available in discrete peripheral vascular embolization devices. Shape memory polymers can exist in two stable shapes; crimped for catheter delivery and expanded for vessel embolization. The expanded shape memory polymer in these new devices is hemostatic, and the porous polymeric scaffold has been shown to support tissue ingrowth and eventually bioabsorbs in preclinical animal studies. This report describes clinical experience with this novel material in vascular plug devices. a prospective, single-arm, safety study at a single center in New Zealand with longer term follow-up via retrospective imaging review. The study device was a pushable shape memory polymer vascular plug with a distal nitinol anchor coil and a proximal radiopaque marker. Ten male patients were each implanted with a single shape memory polymer vascular plug. Three inferior mesenteric arteries and an accessory renal artery were embolized during endovascular aneurysm repair. An internal iliac artery was treated prior to the open surgical repair of aorto-iliac aneurysms. An internal iliac artery and a subclavian artery were embolized to treat/prophylactically address potential endoleaks. A profunda branch was embolized prior to tumor resection, and two testicular veins were embolized to treat varicoceles. Acute technical success of target vessel embolization was achieved in all implantation cases. Patients were followed for 30days as part of the study, and no serious adverse events with a relationship to the study device occurred. No recurrent clinical symptoms attributable to treated vessel embolization or recanalization were documented. There was no evidence of recanalization on retrospective review of follow-up imaging through a mean of 22.2months (range, <1-44months) post-procedure. Shape memory polymer vascular embolization devices were safe and effective over the follow-up period of this small safety study. Further experience and longer term follow-up will assess further applicability.

Thoracoscopic Assisted PleuralPortTM Application in Seven Dogs Affected by Chronic Pleural Effusion.

Chronic non-septic pleural effusion is a condition that frequently may occur because of lung or pleural neoplasia, or chylothorax refractory to surgical treatment, in dogs. Effusion management can be performed with multiple pleurocenteses or the application of chest drains. New modified vascular devices have been used for patients with chronic diseases; they offer the advantage of allowing home management and do not require hospitalization. Eight PleuralPortTM devices were applied in seven dogs during thoracoscopic exploration and biopsy procedures; five were affected by mesothelioma; one by lung metastases from a mammary carcinoma; and one by chronic chylothorax. The median time of surgical procedure was 51 min; one developed pneumothorax post-operatively that resolved within 12 h after repeated drainage; one device was obstructed after 45 days and was successfully managed by flushing. All patients were discharged after 24 h. The median duration of port insertion in cancer patients was 5 months and those dogs were euthanized because of tumor progression; in the dog with chylothorax, the device was removed after 1 year when the effusion had resolved.

A Pilot Estimation of Ventricular-Arterial Coupling Using a Vascular Screening Device (VaSera®).

Non-invasive cardiovascular assessment has become an alternative to invasive techniques. VaSera®, a vascular screening device, measures arterial stiffness with the cardio-ankle vascular index (CAVI); it also measures cardiophysiological variables of ejection time (ET) and pre-ejection period (PEP). We aimed to apply the parameters obtained by VaSera® to estimate heart function based on left ventricular end-systolic elastance/arterial elastance (Ees/Ea) and to assess the minimal required number of measurements for estimation. We conducted an experimental laboratory study for healthy volunteers. Using the previously established formula, the Ees/Ea value of each participant was estimated using ET and PEP values measured by VaSera®. The intraclass correlation coefficient (ICC) assessed the minimum required number of measurements. Concordance correlation coefficient (CCC) and Bland and Altman analysis assessed variation of Ees/Ea estimation against the trimmed average. A total of 660 measurements from 132 participants were included. The Ees/Ea estimates from the VaSera® were 1.5 [1.2, 1.9]. The ICC for Ees/Ea was 0.71 (95% confidence interval: 0.65-0.77), suggesting that four measurements were required. The CCC between the trimmed average of Ees/Ea and the mean of four Ees/Ea estimates was 0.99. Bland and Altman analysis showed excellent agreement for the mean of four Ees/Ea estimates and the trimmed average of Ees/Ea. For screening of heart failure, the Ees/Ea estimated using non-invasive vascular-stiffness assessment device would be tolerable and four sequential measurements were required.

A small-diameter vascular graft immobilized peptides for capturing endothelial colony-forming cells.

Combining synthetic polymers and biomacromolecules prevents the occurrence of thrombogenicity and intimal hyperplasia in small-diameter vascular grafts (SDVGs). In the present study, an electrospinning poly (L)-lactic acid (PLLA) bilayered scaffold is developed to prevent thrombosis after implantation by promoting the capture and differentiation of endothelial colony-forming cells (ECFCs). The scaffold consists of an outer PLLA scaffold and an inner porous PLLA biomimetic membrane combined with heparin (Hep), peptide Gly-Gly-Gly-Arg-Glu-Asp-Val (GGG-REDV), and vascular endothelial growth factor (VEGF). Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle goniometry were performed to determine successful synthesis. The tensile strength of the outer layer was obtained using the recorded stress/strain curves, and hemocompatibility was evaluated using the blood clotting test. The proliferation, function, and differentiation properties of ECFCs were measured on various surfaces. Scanning electronic microscopy (SEM) was used to observe the morphology of ECFCs on the surface. The outer layer of scaffolds exhibited a similar strain and stress performance as the human saphenous vein via the tensile experiment. The contact angle decreased continuously until it reached 56° after REDV/VEGF modification, and SEM images of platelet adhesion showed a better hemocompatibility surface after modification. The ECFCs were captured using the REDV + VEGF + surface successfully under flow conditions. The expression of mature ECs was constantly increased with the culture of ECFCs on REDV + VEGF + surfaces. SEM images showed that the ECFCs captured by the REDV + VEGF + surface formed capillary-like structures after 4weeks of culture. The SDVGs modified by REDV combined with VEGF promoted ECFC capture and rapid differentiation into ECs, forming capillary-like structures in vitro. The bilayered SDVGs could be used as vascular devices that achieved a high patency rate and rapid re-endothelialization.

A 10-Year Analysis of Representation of Women in Patent Applications and NIH Funding in Vascular Surgery

There has been an increasing focus on gender disparities in the medical field and in the field of vascular surgery specifically. We aimed to characterize gender representation in vascular surgery innovation over the past 10years, using metrics of patents and National Institutes of Health (NIH) support. We performed a retrospective review of all vascular-related patent filings (Google Scholar) and NIH-funded grants (NIH RePORTER) over a 10-year period (January 1st, 2012, to December 31st, 2021). Gender-API (Application Programming Interface) was used to identify the gender of the inventors, with manual confirmation of a 10% random sample. Gender representation for patent inventors and grant principal investigators (PIs) were compared using Chi-squared and Student's t-tests as appropriate. Yearly temporal changes in representation were analyzed using Wilcoxon signed-rank tests and linear regression analyses. We identified 2,992 unique vascular device patents with 6,093 associated inventors over 10years. Women were underrepresented in patent authorship overall (11.5%), and were least likely to be listed as first inventor (8.9%) and most commonly fourth and fifth inventors (15.5% and 14.1%, respectively) compared to men. There was no significant change in representation of women inventors over time (-0.2% females per year, 95% confidence interval (CI) -0.54 to 0.10). We identified 1736 total unique NIH grants, with 23.8% of funded projects having women PIs. There was an increase in the proportion of women PIs over time (+1.31% per year, 95% CI 0.784 to 1.855; P<0.001). Projects with women PIs received mean total awards that were significantly lower than projects with men PIs ($350,485±$220,072 vs. $451,493±$411,040; P<0.001), but the overall ratio of funding:women investigators improved over time (+$11,531 per year, 95% CI $6,167 to $16,895; P=0.0011). While we have made strides in increasing the number of women in the surgical research space, there is still room for improvement in funding parity. In addition, we found substantial and persistent room for improvement in representation of women in surgical innovation. As we enter a new frontier of surgery hallmarked by equalizing gender representation, these data should serve as a call-to-action for initiative aimed at rebuilding the foundation of surgical innovations upon equal gender representation.

Prevention and management of paravalvular regurgitation after transcatheter aortic valve implantation.

Management of paravalvular regurgitation (PVR) after transcatheter aortic valve implantation (TAVI). Most patients with mild PVR can be managed medically with periodic imaging to detect any increase in regurgitant severity. In some patients with moderate to severe or severe PVR, medical therapy may be possible using guideline-directed medical therapy for heart failure or haemolytic anaemia. When intervention is needed, surgical aortic valve replacement (SAVR) may be considered, but many of these patients may be high risk for surgery or prefer to avoid surgical intervention. Transcatheter options include a vascular occluder device, a redo TAVI with placement of a second transcatheter valve (TAV-in-TAV), or balloon dilation of the initial TAVI valve.

Assessment of an umbilical venous catheter dwell-time of 8–14 days versus 1–7 days in very low birth weight infacts (UVC – You Will See): a pilot single-center, randomized controlled trial

BackgroundUmbilical venous catheters (UVCs) are used for central vascular access in preterm infants, but controversy exits with regard to the optimum dwell-time. Patients and methodsProspective, randomized controlled trial at a level III University neonatal intensive care unit (NICU), comparing a UVC dwell-time of 1–7 days (control group) to 8–14 days (intervention group) in very low birth weight (VLBW) infants. Primary outcome parameterNumber of infants requiring additional peripherally inserted central catheters (PICC) after removal of UVC. Secondary outcome parametersTotal number of central lines (CL = UVC and PICCs) until time point of full enteral feeds (130–160 mL/kg/d), total number of intravenous vascular catheters, number of CL-associated complications (infection, thrombosis/emboli, organ injury, secondary CL dislocation), number of X-rays for assessment of CL positioning, and days of therapy (DOT) (teicoplanin) for CL-associated blood stream infections (CLABSI). ResultsOf 116 patients screened for eligibility, 63 patients were enrolled – control group: 31 infants, mean gestational age (GA) 280 weeks (standard deviation (SD) 2.6 weeks), mean birth weight (BW) 988.9 g (SD 322.0 g); intervention group: 32 infants, mean GA 285 weeks (SD 3.0 weeks), mean BW 1078.9 g (SD 324.6 g). In the control group, 28 infants required additional PICCs versus 16 in the intervention group (p < 0.001); total number of CLs: control group n = 58 versus intervention group n = 28; p < 0.001, and the total number of venous vascular devices was also significantly higher in the control group (109 versus 61; p = 0.04). No significant differences were seen with regard to CL-associated complications (p = 0.09). The number of X-rays for assessment of correct CL-position significantly lower in the intervention group (144 versus 96; p = 0.03). In the intervention group, length of hospital stay was significantly shorter (88.1 (SD: 35.3 days) versus 68.1 (SD: 32.6 days); p = 0.03) and GA significantly lower at discharge from the hospital (404: SD: 33 weeks) versus 385: SD: 25 weeks; p = 0.02. No differences existed with regard to neonatal morbidities and mortality at 36 weeks gestational age. ConclusionsA longer UVC dwell-time of up to 14 days significantly decreased the number of painful invasive vascular procedures and radiation exposure, and shortened the length of the hospital stay. The findings of our pilot study should be confirmed in a larger, multi-center RCT with the primary focus on catheter-associated complications.

Short Peripheral Venous Catheters Contamination and the Dangers of Bloodstream Infection in Portugal: An Analytic Study.

Peripheral venous catheters (PVCs) are the most used vascular access devices in the world. However, failure rates remain considerably high, with complications such as PVC-related infections posing significant threats to patients' well-being. In Portugal, studies evaluating the contamination of these vascular medical devices and characterizing the associated microorganisms are scarce and lack insight into potential virulence factors. To address this gap, we analyzed 110 PVC tips collected in a large tertiary hospital in Portugal. Experiments followed Maki et al.'s semi-quantitative method for microbiological diagnosis. Staphylococcus spp. were subsequently studied for the antimicrobial susceptibility profile by disc diffusion method and based on the cefoxitin phenotype, were further classified into strains resistant to methicillin. Screening for the mecA gene was also done by a polymerase chain reaction and minimum inhibitory concentration (MIC)-vancomycin as determined by E-test, proteolytic and hemolytic activity on skimmed milk 1% plate and blood agar, respectively. The biofilm formation was evaluated on microplate reading through iodonitrotetrazolium chloride 95% (INT). Overall, 30% of PVCs were contaminated, and the most prevalent genus was Staphylococcus spp., 48.8%. This genus presented resistance to penicillin (91%), erythromycin (82%), ciprofloxacin (64%), and cefoxitin (59%). Thus, 59% of strains were considered resistant to methicillin; however, we detected the mecA gene in 82% of the isolates tested. Regarding the virulence factors, 36.4% presented α-hemolysis and 22.7% β-hemolysis, 63.6% presented a positive result for the production of proteases, and 63.6% presented a biofilm formation capacity. Nearly 36.4% were simultaneously resistant to methicillin and showed expression of proteases and/or hemolysins, biofilm formation, and the MIC to vancomycin were greater than 2 µg/mL. Conclusion: PVCs were mainly contaminated with Staphylococcus spp., with high pathogenicity and resistance to antibiotics. The production of virulence factors strengthens the attachment and the permanence to the catheter's lumen. Quality improvement initiatives are needed to mitigate such results and enhance the quality and safety of the care provided in this field.

Design of artificial vascular devices: Hemodynamic evaluation of shear-induced thrombogenicity

Blood-circulating devices such as oxygenators have offered life-saving opportunities for advanced cardiovascular and pulmonary failures. However, such systems are limited in the mimicking of the native vascular environment (architecture, mechanical forces, operating flow rates and scaffold compositions). Complications involving thrombosis considerably reduce their implementation time and require intensive anticoagulant treatment. Variations in the hemodynamic forces and fluid-mediated interactions between the different blood components determine the risk of thrombosis and are generally not taken sufficiently into consideration in the design of new blood-circulating devices. In this Review article, we examine the tools and investigations around hemodynamics employed in the development of artificial vascular devices, and especially with advanced microfluidics techniques. Firstly, the architecture of the human vascular system will be discussed, with regards to achieving physiological functions while maintaining antithrombotic conditions for the blood. The aim is to highlight that blood circulation in native vessels is a finely controlled balance between architecture, rheology and mechanical forces, altogether providing valuable biomimetics concepts. Later, we summarize the current numerical and experimental methodologies to assess the risk of thrombogenicity of flow patterns in blood circulating devices. We show that the leveraging of both local hemodynamic analysis and nature-inspired architectures can greatly contribute to the development of predictive models of device thrombogenicity. When integrated in the early phase of the design, such evaluation would pave the way for optimised blood circulating systems with effective thromboresistance performances, long-term implantation prospects and a reduced burden for patients.

Octyl-butyl-cyanoacrylate glue for securement of peripheral intravenous catheters: A retrospective, observational study in the neonatal population.

Evidence-based insertion and maintenance strategies for neonatal vascular access devices (VAD) exist to reduce the causes of VAD failure and complications in neonates. Peripheral intravenous catheter failure and complications including, infiltration, extravasation, phlebitis, dislodgement with/without removal, and infection are majorly influenced by catheter securement methods. A retrospective, observational study using routinely collected data on intravenous device use in a large neonatal intensive care unit in Qatar. A 6-month historical cohort was compared with a 6-month cohort after the introduction of an octyl-butyl-cyanoacrylate glue (CG). In the historical cohort, the catheter was secured using a semi-permeable transparent membrane dressing while in the CG cohort, CG was applied at the insertion site on initial insertion and after any dressing change. This was the only variable intervention between both groups. A total of 8330 peripheral catheters were inserted. All catheters were inserted and monitored by members of the NeoVAT team. 4457 (53.5%) were secured with just a semi-permeable transparent dressing and 3873 (46.5%) secured a semi-permeable transparent dressing with the addition of CG. The odds ratio for premature failure after securement with CG was 0.59 (0.54-0.65) when compared to the catheters secured with a semi-permeable transparent dressing, which was statistically significant (p < 0.001). The correlation between the occurrence of a complication and the use of CG for device securement was significant (p < 0.001). The risk of developing device-related phlebitis and premature device removal, increased significantly if CG was not used for adjunct catheter securement. In parallel with the currently published literature, this study's findings support the use of CG for vascular device securement. When device securement and stabilization concerns are most pertinent CG is a safe and effective adjunct to reducing therapy failures in the neonatal patient population.

Arteriovenous shunt status post-coronary artery bypass graft surgery treated with microcoil placement: A case report

Accidental cardiac arteriovenous (AV) anastomoses is a rare but severe complication of coronary artery bypass grafting. This can result in high output heart failure if left untreated. Little research has been done on the mainstays of treatment for this condition. Our patient is an 82-year-old male with a history of known coronary artery disease, status post-coronary bypass grafting surgery, presented with increasing shortness of breath, which was initially determined clinically to be due to high output heart failure, which was later confirmed during cardiac catheterization procedure. Coronary cardiac catheterization was carried out 2 weeks prior at an outside hospital for which the graft, which is supposed to be anastomosed of the circumflex, inadvertently anastomosed to the coronary sinus. The patient returned to the cardiac catheter lab and repeat angiography was performed. The left to right shunt was subsequently embolized using microcoils. He tolerated the procedure well. No recurrent anginal and/or heart failure symptoms were present. Interventional cardiology began the procedure by gaining right common femoral access. Next the saphenous vein graft to the coronary sinus was engaged with a 6 French JRy (Medtronic Inc., Minneapolis, MN) guide catheter and a 0.014” coronary wire was placed into the graft. Then interventional radiology advanced a 2.4 French microcatheter (Terumo, Ann Arbor, MI USA) over the 0.014” wire (Abbott Vascular Devices, Plymouth MN) into the mid to distal aspect of the bypass graft. Four detachable 0.018” microcoils (Terumo, Ann Arbor, MI USA) were carefully placed within the bypass graft. Subsequent angiogram demonstrated complete occlusion of the bypass graft with resolution of the AV shunt. Due to the acuity of the patient’s symptoms and the long timeframe from originally attempting stenting, no additional attempts to stent the circumflex were performed. Follow-up angiogram through the base catheter demonstrates complete occlusion of the bypass graft with resolution of the AV shunt. No contrast was seen entering the coronary sinus. The patient tolerated the procedure well with no immediate complications. Estimated blood loss was &lt;10 mL. The patient was admitted overnight for further evaluation. No shortness of breath noted. He was discharged in good condition the following day. Accidental cardiac AV anastomosis is a rare complication of coronary artery bypass grafting that could lead to high output heart failure. In such cases, catheter directed embolization with microcoils can be done to occlude the AV shunt created by the previously placed cardiac catheter with resolution of heart failure symptoms.

Sirolimus-Embedded Silk Microneedle Wrap to Prevent Neointimal Hyperplasia in Vein Graft Model.

We investigated the role of a sirolimus-embedded silk microneedle (MN) wrap as an external vascular device for drug delivery efficacy, inhibition of neointimal hyperplasia, and vascular remodeling. Using dogs, a vein graft model was developed to interpose the carotid or femoral artery with the jugular or femoral vein. The control group contained four dogs with only interposed grafts; the intervention group contained four dogs with vein grafts in which sirolimus-embedded silk-MN wraps were applied. After 12-weeks post-implantation, 15 vein grafts in each group were explanted and analyzed. Vein grafts applied with the rhodamine B-embedded silk-MN wrap showed far higher fluorescent signals than those without the wrap. The diameter of vein grafts in the intervention group decreased or remained stable without dilatation; however, it increased in the control group. The intervention group had femoral vein grafts with a significantly lower mean neointima-to-media ratio, and had vein grafts with an intima layer showing a significantly lower collagen density ratio than the control group. In conclusion, sirolimus-embedded silk-MN wrap in a vein graft model successfully delivered the drug to the intimal layer of the vein grafts. It prevented vein graft dilatation, avoiding shear stress and decreasing wall tension, and it inhibited neointimal hyperplasia.

Acquisition of New Philips Affiniti 30 Vascular Color Doppler Ultrasound Device - Cost Benefit Analysis to Reduce Cardiosurgical Patients' Treatment.

Cerebrovascular accidents (CVI) are considered the second most serious complication in cardiac surgery patients with a frequency of 10%. By preventing complications of surgical treatment, using a Color Doppler ultrasound (CDU) device, in the population of cardiac surgery patients, the unplanned costs of prolonged postoperative treatment would be reduced. To prove that the acquisition and use of the newly developed CDU device "Affinit 30" is completely economical, profitable and medically justified. Numerical parameters of the treatment of cardiovascular patients were analyzed (number of procedures, number of days in the intensive care unit, cost of additional consultative services of the clinic for radiology and neurology), and the calculated economic value of the potential investment, as well as the cost of preventing surgical complications, by purchasing and installing a new modern CDU device. The profitability of the investment was assessed using the economic parameters Net Present Value (NPV) of the investment, Internal rate of return (IRR) and Profitability Index (PI). A mathematical calculation with the given parameters yields NPV = 948,850 KM and IRR of 273% when applied to the given parameters. The PI value is 12.6, which matches the previously calculated NPV and IRR values. The acquisition and use of the newly developed CDU device "Affinit 30" is economically profitable and medically justified. This is shown by the calculated values of the economic parameters Net Present Value of the investment (NPV), Internal rate of return (IRR) and the Profitability Index (PI).