Vascular access challenges in hemodialysis patients with superior vena cava syndrome

BACKGROUND

Superior vena cava syndrome in hemodialysis patients resulting from previous or current use of a tunneled central vein catheter is a rare but potentially severe condition. Two aspects have to be addressed during management and treatment: the restoration of central venous flow and the creation of an alternative vascular access to guarantee hemodialysis.

RESEARCH DESIGN

Conforming to the current guidelines and literature, we present a stepwise approach and discuss therapeutic options. The removal of the tunneled central vein catheter should be attempted and a native vascular access created whenever feasible.

RESULTS

First, an upper extremity AVF should be preserved or, as in our case, made functional. Endovascular treatment of CVSO should primarily consist of balloon dilatation. Placement of a stent or stent graft should be considered as a secondary option. HeRO graft placement may be considered in recurrent CVSO and recanalization with a Surfacer. LL-AVF or AVG need to be discussed and may be an alternative for certain HD patients when the risk of lower limb ischemia and infection is considered.

CONCLUSION

Several therapeutic options are available and the basic principles are well established in the literature, although the level of evidence is not high. Therefore, we propose a stepwise and interdisciplinary approach to guide the challenging decision-making process in SVC.

Endovascular maneuvers for contralateral stent graft limb misplacement in endovascular aortic repair

Cannulation and placement of the contralateral stent graft limb during endovascular aortic repair (EVAR) procedure are crucial steps as mispositioning may lead to conversion to open aortic repair. Endovascular bail-out strategies for stent graft relocation in EVAR are underreported though detailed knowledge may facilitate application and prevent conversion. We present three endovascular bail-out strategies for repositioning of a mispositioned contralateral stent graft limb. (1) Retraction of the mispositioned component with an inflated reliant balloon and placement of an interposition stent graft after successful cannulation; (2) Push-maneuver of the mispositioned stent graft into the infrarenal aortic aneurysm with an inflated reliant balloon supported by a large lumen introducer sheath and (3) Parallel placement of a second contralateral stent graft limb displacing the mispositioned one against the atrial wall in cases with adequate vessel diameter. Prevention of stent graft mispositioning by applying recognized tests to ensure correct placement are essential, following the slogan: check twice, deploy once.

Early-cannulation arteriovenous grafts: Multidisciplinary learning is essential to optimize outcomes

BACKGROUND

It is likely that there will be an increasing role for early-cannulation arteriovenous grafts (ecAVG) with a wider recognition of the need to tailor vascular access to avoid futile procedures and unnecessary TCVC. However, experience of these products is not common and limited to early surgical adopters, with little information on the systemic changes and multi-disciplinary care needed to optimize outcomes. The aim of this study was to report the impact of a multi-disciplinary approach on quantifiable outcomes.

METHODS

A retrospective analysis of a prospectively maintained database of 295 ecAVG implanted over an 8-year time-period was performed. Indicative outcomes were chosen to reflect nephrology (patient selection), nursing care (cannulation complications of infection and pseudoaneurysm) and radiology (thrombosis) on cumulative impact (functional patency) over three distinct time periods.

RESULTS

The incidence of ecAVG increased 10-fold over the three time periods. The use of ecAVG changed significantly from salvage tertiary access to TCVC avoidance and salvage of existing AVF. Nursing complications reduced markedly with significantly fewer over-cannulation episodes and pseudo-aneurysms. With an improved pro-active surveillance programme, the time to first thrombosis doubled and the risk of thrombosis halved. Ultimately this resulted in significantly improved functional patency with a risk of ecAVG loss less than one-third by the last time-period.

CONCLUSIONS

All aspects of ecAVG use require scrutiny and critical appraisal. Failure or success is not simply achieved by performing good technical surgery with an efficacious product, but by the care taken across a wide range of elements spanning case selection, implantation, use and maintenance.

A Novel Percutaneous Technique for Aorto-Iliac Thrombectomy without the Risk of Embolization

Classic surgical thrombectomy of the aorta and iliac arteries through an incision in the groin vessels harbors the risk of embolization to the viscero-renal as well as hypogastric arteries, while percutaneous endovascular thrombectomy techniques can lead to peripheral embolization to the lower limbs. Therefore, we describe a novel, percutaneous technique that tackles the above issues. Furthermore, we also present our initial experience using the technique. The principle of the technique is to percutaneously place large-bore sheaths in the iliac arteries that deliberately occlude the latter to protect the lower limbs from embolization. Through one of these sheaths, over wire Fogarty^® catheters can be placed and inflated in the ostia of the coeliac trunk, superior mesenteric artery, renal arteries, and hypogastric arteries as needed. A large thrombectomy balloon catheter is then used to bring any aorto-iliac thrombus into the sheaths, whereafter the thrombus is removed from the sheaths by simply deflating their valves. Additional endovascular procedures of the aorto-iliac branches can be performed as needed. We report nine procedures in 8 patients (4 males and 4 females) with a median age of 63 (53-68.5). Additional endovascular procedures were performed in 6 (66.7%) procedures. All but one procedure were technically successful, and all patients had palpable foot pulses on completion of the procedures, while no patient had clinical signs of peripheral embolization. This technique is a very valid addition to the vascular surgeon's armamentarium when treating aorto-iliac thrombotic events because it is minimally invasive while still protecting against embolization and offering the flexibility to perform a wide range of additional endovascular procedures where needed.

Pre-emptive or reactive treatment, angioplasty or stent-graft? The outcome for interventions for venous stenosis in early-cannulation arteriovenous grafts

BACKGROUND

Early-cannulation arteriovenous grafts (ecAVG) have good initial patency, but frequent episodes of reintervention for venous stenosis (VS) and thrombosis limit their use. Stent grafts (SG) have shown promise in reducing re-interventions and improving functional patency for dysfunctional ecAVG and recurrent VS. There is little data on the impact of stent grafts as the first elective procedure for VS. The aim of this study was to determine firstly, if treating VS whilst asymptomatic has a better outcome than treating after presentation with thrombosis; and secondly, to determine the best initial treatment for asymptomatic VS: SG or angioplasty.

METHODS

A retrospective study was performed of 259 ecAVG with a sutured anastomosis. The case-mix and outcomes of 153 who presented with VS was analysed by presentation (elective at surveillance or emergency following thrombosis), and then for only elective patients, by treatment (SG vs angioplasty).

RESULTS

There was no significant difference in case-mix and time to presentation by mode of presentation (100 elective and 53 with thrombosis) other than a higher rate of pro-thrombotic disorders in thrombosed ecAVG. Thrombosed ecAVG had poorer outcomes with increased re-intervention rates and thrombosis in the following year, and reduced long-term functional patency. In patients presenting electively, primary SG rather than angioplasty led to significantly reduced thrombosis rates, a longer time to re-intervention in the following year, and superior long-term functional patency. The use of SG was the same in both groups. Both the mode of presentation and the type of intervention performed were independently predictive of a poorer subsequent functional patency.

CONCLUSIONS

Primary elective stent-grafting may be the optimal strategy to reducing maintenance costs with ecAVG.

Pre-procedure imaging planning for dialysis access in patients with end-stage renal disease using ultrasound and upper extremity computed tomography angiography: a narrative review

Background and Objective

The incidence of patients with end-stage renal disease (ESRD) and subsequent need for dialysis is continuously rising. The detailed preoperative planning and careful creation of a functioning access for hemodialysis as a bridge to transplant or as a long-term solution, has a crucial role to reduce vascular access associated morbidity and mortality and improve quality of life of the ESRD patient population. In addition to a detailed medical workup including physical exam, a variety of imaging modalities exist to support further decision making with regard to the best suited vascular access for each individual patient. These modalities provide both, a comprehensive anatomical overview of the vascular tree and specific pathologic findings, which may increase the likelihood of access failure or insufficient access maturation. This manuscript aims to provide a comprehensive review of current literature and an overview of the different imaging modalities in vascular access planning. Additionally, we provide a step-by-step planning algorithm for hemodialysis access creation.

Methods

After searching in PubMed and Cochrane database of systematic review, we reviewed eligible English literatures published up to 2021, including guidelines and meta-analyses, retrospective and prospective cohort studies.

Key Content and Findings

Duplex ultrasound is widely accepted as first line imaging tool for preoperative vessel mapping. However, this modality has its inherent limitations, therefore specific questions can be assessed using digital subtraction angiography (DSA) or venography and computed tomography angiography (CTA). These modalities are more invasive, are associated with radiation exposure and require nephrotoxic contrast agents. Magnetic resonance angiography (MRA) may be an alternative in selected centers with available expertise.

Conclusions

Pre-procedure imaging recommendations are mainly based on retrospective (register-) studies and case-series. Prospective studies and randomized trials are primarily related to access outcomes in ESRD patients who underwent preoperative duplex ultrasound. Comparative prospective data related to invasive DSA and non-invasive cross-sectional imaging (CTA or MRA) are lacking.

Practical guide of vascular ultrasound in arteriovenous fistulae

The use of vascular ultrasound, especially with the increasing prevalence of percutaneous arteriovenous fistulas, has taken a central role as a diagnostic and therapeutic imaging procedure in vascular access creation. The current review article stresses the importance of vascular ultrasound in arteriovenous fistula, from planning to creation to maintenance. It summarises and gives practical guidance regarding sonographic criteria for vascular access procedure planning, the application of vascular ultrasound intraoperatively and during follow-up. Ultrasound education and training modalities to meet high standards of patient care in hemodialysis are presented.

Ultrasound-Guided Percutaneous Arteriovenous Fistula Creation Simulation Training in a Lifelike Flow Model

Objectives: To assess the feasibility and training effect of simulation training for ultrasound-guided percutaneous arteriovenous fistula (pAVF) creation in a lifelike flow model. Methods: Twenty vascular trainees and specialists were shown an instructional video on creating a pAVF in a dedicated flow model and then randomized to a study or control group. The procedure was divided into five clearly defined steps. Two observers rated the performance on each step, and the time to perform the exercise was recorded. The study group participants underwent supervised hands-on training on the model before performing a second rated pAVF creation. All participants subsequently completed a feedback questionnaire. Results: After supervised simulation training, the study groups participants increased their mean performance rating from 2.2 ± 0.9 to 3.2 ± 0.7. A mean of 3.8 ± 0.8 procedure steps was accomplished independently (control group 2.1 ± 1.4; p < 0.05). The time taken to perform the procedure was 15.6 ± 3.8 min in the study group (control group 27.2 ± 7.3, p < 0.05). The participants with previous experience in ultrasound-guided vascular procedures (n = 5) achieved higher overall mean scores 3.0 ± 0.8 and accomplished more steps without assistance (2.0 ± 1.0) during the simulation training compared to their inexperienced peers (1.5 ± 0.3 and 0.8 ± 0.4, respectively). The feedback questionnaire revealed that the study group participants strongly agreed (n = 7) or agreed (n = 3) that training on the simulation model improved their skills regarding catheter handling. Conclusions: The study group participants increased their overall performance after training on the simulator. More experienced attendees performed better from the beginning, indicating the model to be lifelike and a potential skill assessment tool. Simulation training for pAVF creation using a lifelike model may be an intermediate step between acquiring ultrasound and theoretical pAVF skills and procedure guidance in theatre. However, this type of training is limited by its reliance on the simulator quality, demonstration devices and costs.

Open aneurysm repair in patients with concomitant abdominal aortic aneurysm and aorto-iliac occlusive disease is associated with a high mortality and surgical complication rate

AIM OF THE STUDY

To evaluate whether the outcome after open aneurysm repair combined with aorto-femoral bypass in patients with concomitant abdominal aortic aneurysm (AAA) and aorto-iliac occlusive disease (AIOD) is inferior to open aneurysm repair for isolated AAA or aorto-femoral bypass for isolated AIOD.

METHODS

We performed a retrospective analysis of 30-day mortality, 1-year mortality and surgical complications of consecutive patients undergoing elective aneurysm repair, aorto-femoral bypass or a combination of these at two vascular surgery departments from 2003 to 2013. Potential risk factors were investigated by multivariable analysis.

RESULTS

Overall, 511 patients underwent open repair for isolated AAA, 104 aorto-femoral bypass for isolated AIOD and 46 open AAA repair combined with aorto-femoral bypass for concomitant AAA and AIOD. Surgical complications occurred in 17% of AAA, 23% of AIOD and 37% of combined patients (odds ratio [OR] combined vs AAA 2.76, 95% confidence interval [CI] 1.43-5.34; p = 0.003). Colon ischaemia occurred in 3.7% of AAA, 2.9% of AIOD and 13% of combined patients (incicidence rate ratio [IRR] combined vs AAA 3.27, 95% CI 1.37-7.81; p = 0.01). The 30-day mortality was 3.1% in AAA, 4.8% in AIOD, and 11% in combined patients (IRR combined vs AAA 3.17, 95% CI 1.26-7.96; p = 0.01). One-year mortality was 5.7% in AAA, 5.8% in AIOD and 15% in combined patients (IRR combined vs AAA 2.50, 95% CI 1.17-5.35; p = 0.02).

CONCLUSIONS

Combined AAA repair and aorto-femoral bypass has a significantly higher 30-day mortality and postoperative complication rate than isolated AAA repair. Patients with concomitant AAA and AIOD thus represent a high-risk population, which should be considered when deciding on the indication for AAA treatment.

Multicenter observational study of the gore excluder conformable endograft for endovascular abdominal aortic repair: Initial results

Objective

Endovascular repair (EVAR) has become the standard of care for treatment of abdominal aortic aneurysms. However, a significant number of EVAR remains outside the IFU, especially in cases of severe proximal angulation (&gt;60 degrees), resulting in failure. The new device GORE EXCLUDER Conformable AAA Endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz) has been designed to accommodate neck angulation, due to conformability and angulation control. The aim of this multicenter study is to report the initial results of this device.

Methods

From March 2019 to January 2021, the data of all consecutive patients with AAA treated with the Gore Excluder Conformable endograft at 4 vascular centers were reviewed. Patients were followed using a standardized protocol, with CT-scan at 1, 6 and 12 months, and then yearly. The primary endpoint was technical success and secondary outcomes were postoperative morbidity, rate of endoleak (EL) and any aneurysm-related re-interventions during follow-up.

Results

Among the 32 patients included, most were men with a mean age of 77 years old (range 60-92). Half of patients were smokers and 72% had hypertension. The mean diameter of AAA was 62 mm (47-90). The mean length of aortic neck was 26 mm (10-69), the mean diameter 23 mm (16-31) and the median neck angulation was 81 degrees (range 40-110). The mean procedural duration was 102 min (54-153) with a mean time of scopy of 24 min (8-47) and a total volume of contrast of 101 ml (40-165). Thirteen iliac branch device have been used in 7 patients. The technical success was 97% with 1 type Ia EL (3%). In the post-operative period, 4 medical and 3 surgical complications were observed. Two reinterventions were needed with an iliac stenting for a stenosis and a correction of a femoral false aneurysm. During the mean follow-up of 7 months, 2 type Ia ELs were observed. One spontaneously resolved and the other one was followed. One distal limb extension was succesfully implanted at 3 months for a type Ib EL for a total rate of reintervention of 9%. No migration was observed. No death occured.

Conclusion

The use of the Gore Excluder Conformable endograft seems to be safe and effective in difficult anatomies and especially high angulation. It allows for precise deployment without the need for additional contrast or operation time. Longer follow-up and more patients are required to confirm these excellent initials results.

Tele-proctoring in vascular surgery implementing percutaneous creation of arteriovenous fistula

Objective

Percutaneous ultrasound-guided creation of an arteriovenous fistula (pAVF) for hemodialysis access is a relatively novel procedure with promising technical success and patency rates. The vascular surgery departments of two collaborating Swiss hospitals had decided to introduce the technique to their services. A surgeon experienced in the technique (AM) was supposed to come to Switzerland and proctor the first four procedures. Due to the SARS-CoV-2 pandemic and travel restrictions, this was not possible and we decided to perform the first four pAVF procedures tele-proctored via a video conference system. We present the setup and our experience with tele-proctoring.

Methods

The setup relied on an all-in-one live video production device, video encoder, video streamer and video recorder (Pearl-2, Epiphan), which made it possible to simultaneously transmit the live image from the ultrasound device (GE Logiq S8, linear probe 9L-D) and a live image from a video camera (JVC Camcorder G/-HM440E, Japan), both connected via HDMI (Figure). The live stream was shared with the proctor in France and the device support team in the US, using an encrypted Swiss video client (www.vitimway.ch). The setup was tested with all parties three days in advance.

Results

All 4 procedures started with a verbal briefing and a live ultrasound scan. All steps of the procedures were taken under the proctor’s instruction and supervision. The proctor gave on average 21 instructions per procedure. An average 4 were device-related but these became less frequent as we proceeded. The operators consulted the proctor on average 5 times per procedure. The average duration of the procedure was 34 min. The pAVF creation was successful in all 4 patients, with an average fistula flow measured at the end of the procedure of 600 ml/min.

Conclusion

Our experience showed us that pAVF creation, which is a procedure performed entirely under sonographic guidance lends itself particularly well to tele-proctoring. The simultaneous transmission of the live sonographic image and the live image of the operators' hands allowed the proctor to supervise and correct the key steps of the procedures. The simplicity of the set-up and the quality of proctor-operator interaction was such a positive experience that we can well envisage a much wider use of tele-proctoring in the future.

Early-cannulation arteriovenous grafts are safe and effective in avoiding recurrent tunneled central catheter infection

Objective

Tunneled central venous catheter infection (TCVCi) is a common complication that often necessitates removal of the TCVC and a further TCVC. Theoeretically, insertion of an early-cannualtion graft (ecAVG) early after TCVC infection is possible but not widely practiced with concerns over safety and infection in the ecAVG. With 8 years of ecAVG experience, the aim of this study was to compare the outcomes following TCVC infection, comparing replacement with TCVC (TCVCr) versus immediate ecAVG (ecAVGr).

Methods

Retrospective comparison of two cohorts, who underwent replacement of an infected TCVC either by an early cannulation graft (n = 18) or by a further central catheter (n = 39).

Data were abstracted from a prospectively completed electronic patient record and collected on patient demographics, TCVC insertion, duration and infection, including culture proven bacteriaemia and subsequent access interventions.

Results

18/299 patients identified from 2012-2020 had an ecAVG implanted as treatment for a TCVCi. In a one-year time-period (1/1/2015 -31/12/2015) out of 222 TCVC inserted, 39 were as a replacement following a TCVCi. No patient with an ecAVGr developed an immediate infection, nor complication from the procedure. The rate of subsequent vascular access infection was significantly more frequent for those with TCVCr than with an ecAVGr (0.6 vs. 0.1/patient/ 1000 HD days, p &lt; 0.000). The number of further TCVC required was significantly higher in the TCVCr group (7.1 vs. 0.4/patient/ 1000 HD days, p = 0.000).

Conclusion

An ecAVG early following a TCVC infection is safe, reduces the incidence of subsequent infectious complications and reduces the number of TCVC required, with a better functional patency.

First experience with percutaneous arteriovenous fistula creation using the Ellipsys® vascular access system

Objective

Percutaneous creation of arteriovenous fistulae (pAVF) has been developed as an alternative to the creation of an upper arm cephalic or basilic vein fistula. Several studies have shown high technical success rates and comparable time of maturation. To our knowledge, the technique has not been used in Switzerland before.

Methods

Prospective data collection of the first consecutive patients undergoing the creation of pAVF between April and July 2020 at two vascular surgery centres.

Results

Seven patients underwent pAVF creation with the Ellipsys® vascular access system under regional anaesthesia for maximum vasodilation. The procedures were performed entirely under sonographic control without the use of fluoroscopy. The cephalic or basilic vein was punctured and the puncture needle advanced under sonographic control through the cubital perforator vein into the proximal radial artery. The Ellipsys® catheter was advanced over a guidewire and activated to create the fistula between the proximal radial artery and the perforator vein. The fistula was further dilated with a 5mm PTA balloon. We achieved technical success in 6 patients. In one patient with small and spastic vessels, the needle could not be advanced into the radial artery. A conventional upper arm cephalic fistula was created during the same procedure. In three patients primary maturation was achieved and the cephalic vein or distal basilic vein could be punctured for dialysis without any adjunct procedures. One patient required three additional procedures before the fistula could be used successfully (additional angioplasty of the fistula, superficialisation of the basilic vein and correction of a cubital vein stenosis by excision and end-to-end anastomosis). One patient required superficialisation of the basilic vein and one patient transposition of the arterialised brachial vein. Maturation was achieved in six pAVF after a mean of 158 days with a mean fistula flow of 920 ml/ min.

Conclusion

We achieved high technical success and maturation rates in our first patients undergoing pAVF creation with the Ellipsys® system. Prerequisites are suitable anatomy of the cubital perforator vein and good skills in sonography and endovascular techniques. We believe that pAVF is a promising alternative to the creation of a conventional upper arm fistula in patients unsuitable for a distal radio-cephalic fistula.

Patient characteristics predict patency of early-cannulation arteriovenous grafts

There is a new emphasis on tailoring appropriate vascular access for hemodialysis to patients and their life-plans, but there is little known about the optimal use of newer devices such as early-cannulation arteriovenous grafts (ecAVG), with studies utilising them in a wide variety of situations. The aim of this study was to determine if the outcome of ecAVG can be predicted by patient characteristics known pre-operatively. This retrospective analysis of 278 consecutive ecAVG with minimum one-year follow-up correlated functional patency with demographic data, renal history, renal replacement and vascular access history. On univariate analysis, aetiology of renal disease, indication for an ecAVG, the number of previous tunnelled central venous catheters (TCVC) prior to insertion of an ecAVG, peripheral vascular disease, and BMI were significant associates with functional patency. On multivariate analysis the number of previous TCVC, the presence of peripheral vascular disease and indication were independently associated with outcome after allowing for age, sex and BMI. When selecting for vascular access, understanding the clinical circumstances such as indication and previous vascular access can identify patients with differing outcomes. Importantly, strategies that result in TCVC exposure have an independent and cumulative association with decreasing long-term patency for subsequent ecAVG. As such, TCVC exposure is best avoided or minimised particularly when ecAVG can be considered.

Early-Cannulation Arteriovenous Grafts Are Safe and Effective in Avoiding Recurrent Tunneled Central Catheter Infection

OBJECTIVES

Tunneled central venous catheter infection (TCVCi) is a common complication that often necessitates removal of the TCVC and replacement by a further TCVC. Theoretically, insertion of an early - cannulation graft (ecAVG) early after TCVC infection is possible but not widely practiced with concerns over safety and infection in the ecAVG. With 8 years of ecAVG experience, the aim of this study was to compare the outcomes following TCVC infection, comparing replacement with TCVC (TCVCr) versus immediate ecAVG (ecAVGr).

DESIGN

Retrospective comparison of 2 cohorts, who underwent replacement of an infected TCVC either by an early cannulation graft (n = 18) or by a further central catheter (n = 39).

METHODS

Data were abstracted from a prospectively completed electronic patient record and collected on patient demographics, TCVC insertion, duration and infection, including culture proven bacteriaemia and subsequent access interventions.

RESULTS

Eighteen of 299 patients identified from 2012 to 2020 had an ecAVG implanted as treatment for a TCVCi. In a 1-year time-period (January 1, 2015-December 31, 2015) out of 222 TCVC inserted, 39 were as a replacement following a TCVCi. No patient with an ecAVGr developed an immediate infection, nor complication from the procedure. The rate of subsequent vascular access infection was significantly more frequent for those with a TCVCr than with an ecAVGr (0.6 vs. 0.1/patient/1000 HD days, P< 0.000). The number of further TCVC required was significantly higher in the TCVCr group (7.1 vs. 0.4/patient/1000 HD days, P= 0.000).

CONCLUSIONS

An ecAVG early following a TCVC infection is safe, reduces the incidence of subsequent infectious complications and reduces the number of TCVC required, with a better functional patency.

Evaluation of malignant effusions using MR-based T1 mapping

Our aim was to investigate the diagnostic yield of rapid T1-mapping for the differentiation of malignant and non-malignant effusions in an ex-vivo set up. T1-mapping was performed with a fast modified Look-Locker inversion-recovery (MOLLI) acquisition and a combined turbo spin-echo and inversion-recovery sequence (TMIX) as reference. A total of 13 titrated albumin-solutions as well as 48 samples (29 ascites/pleural effusions from patients with malignancy; 19 from patients without malignancy) were examined. Samples were classified as malignant-positive histology, malignant-negative histology and non-malignant negative histology. In phantom analysis both mapping techniques correlated with albumin-content (MOLLI: r = − 0.97, TMIX: r = − 0.98). MOLLI T1 relaxation times were shorter in malignancy-positive histology fluids (2237 ± 137 ms) than in malignancy-negative histology fluids (2423 ± 357 ms) as well as than in non-malignant-negative histology fluids (2651 ± 139 ms); post hoc test for all intergroup comparisons: < 0.05. ROC analysis for differentiation between malignant and non-malignant effusions (malignant positive histology vs. all other) showed an (AUC) of 0.89 (95% CI 0.77–0.96). T1 mapping allows for non-invasive differentiation of malignant and non-malignant effusions in an ex-vivo set up.

External stenting and disease progression in vein grafts 1 year after open surgical repair of popliteal artery aneurysm

OBJECTIVE

Open surgical repair remains the gold standard treatment for popliteal artery aneurysms (PAA). The objective of this study was to evaluate the safety of external stenting and its medium-term effect on vein graft disease after open PAA repair.

METHODS

Between December 2017 and September 2019, 12 consecutive patients with PAA underwent open surgical repair with externally stented saphenous vein grafts. Duplex ultrasound scanning of the grafts was performed at discharge and at 3, 6, and 12 months after the procedure to evaluate graft patency, average lumen diameter and lumen uniformity.

RESULTS

Eleven patients underwent aneurysm ligation and bypass grafting and one patient was treated with aneurysm exclusion and interposition of a venous segment. External stenting of the vein graft was successful in all patients. The mean follow-up time was 12 months (range, 7-17 months), with a primary patency rate of 100% and no graft revisions or reinterventions. The mean lumen diameters at 3, 6, and 12 months were 5.9 ± 1.2 mm, 5.7 ± 0.8 mm, and 5.7 ± 0.7 mm, respectively, with no significant changes between 3 and 6 (P = .34) and between 6 and 12 months (P = .34). The coefficient of variance at 3, 6, and 12 months was 8.2 ± 9.3, 9.4 ± 7.2, and 10.4 ± 8.9, respectively, with no significant change between 3 and 6 months (P = .78) or 6 and 12 months (P = .98). No mortality or amputations were recorded throughout the follow-up period.

CONCLUSIONS

External stenting of vein grafts in open surgical repair of PAA is feasible and safe. This technique may potentially improve the outcomes of surgical repair in patients with PAA.

Application and implications of a standardised reporting system for arteriovenous access graft infection

INTRODUCTION

The perception that arteriovenous graft infection (AVGi) is frequent and severe is not based on contemporary data from large units using modern AVG. Furthermore, older reports compounded misperceptions by using non-standardised reporting that prevents easy comparison against the alternative modalities. The aim of this article is to use a recently published reporting scheme to analyse the frequency, management and outcome of AVGi in a large series of sequential early-cannulation AVG with long-term follow-up.

METHODS

A single-center series analysis was performed of 277 early-cannulation AVG with minimum 1-year follow-up (total 120,082 days). Infections relating to the AVG were classified, root-cause analysed and the outcomes presented.

RESULTS

Sixteen percent of all AVG implanted (51 episodes) developed infection related to the AVG. Primary AVGi (related to the insertion procedure or within 28 days) occurred in 9 (3%); secondary AVGi (related to AVG in use) occurred 33 times (rate 0.27/1000 haemodialysis days), at a mean of 382 days, and tertiary AVGi (in AVG no longer in use) occurred nine times. Only 1/3 of all AVGi led to bacteraemia, and ½ did not lead to loss of functional access.

SUMMARY

AVG infection is not common, caused a systemic infection in only one-third, did not lead to metastatic infection, and importantly, was treatable without loss of access in one-half of all cases. Using an objective system that discriminates between aetiology and outcome allows a more complete objective understanding of relative infection risks and outcomes for AVG that can inform discussions with patients requiring vascular access for haemodialysis.

Quantitative MRI of the liver: Evaluation of extracellular volume fraction and other quantitative parameters in comparison to MR elastography for the assessment of hepatopathy

BACKGROUND

Chronic liver diseases pose a major health problem worldwide, while common tests for diagnosis and monitoring of diffuse hepatopathy have considerable limitations. Preliminary data on the quantification of hepatic extracellular volume fraction (ECV) with magnetic resonance imaging (MRI) for non-invasive assessment of liver fibrosis are encouraging, with ECV having the potential to overcome several of these constraints.

PURPOSE

To clinically evaluate ECV provided by quantitative MRI for assessing the severity of liver disease.

MATERIALS AND METHODS

In this prospective study, multiparametric liver MRI, including T1 mapping and magnetic resonance elastography (MRE), was performed in subjects with and without hepatopathy between November 2018 and October 2019. T1, T2, T2*, proton density fat fraction and stiffness were extracted from parametric maps by regions of interest and ECV was calculated from T1 relaxometries. Serum markers of liver disease were obtained by clinical database research. For correlation analysis, Spearman rank correlation was used. ROC analysis of serum markers and quantitative MRI data for discrimination of liver cirrhosis was performed with MRE as reference standard.

RESULTS

109 participants were enrolled (50.7 ± 16.1 years, 61 men). ECV, T1 and MRE correlated significantly with almost all serum markers of liver disease, with ECV showing the strongest associations (up to r = 0.67 with MELD, p < 0.01). ECV and T1 correlated with MRE (0.75 and 0.73, p < 0.01 each). ECV (AUC 0.89, cutoff 32.2%, sensitivity 85%, specificity 87%) and T1 mapping (AUC 0.85, cutoff 592.5 ms, sensitivity 83%, specificity 75%) featured good performances in detection of liver cirrhosis with only ECV performing significantly superior to model of end stage liver disease (MELD), AST/ALT ratio and international normalized ratio (p < 0.01, respectively).

CONCLUSION

Quantification of hepatic extracellular volume fraction with MRI is suitable for estimating the severity of liver disease when using MRE as the standard of reference. It represents a promising tool for non-invasive assessment of liver fibrosis and cirrhosis.

Parameters predicting COVID-19-induced myocardial injury and mortality

Clinical manifestations of COVID-19 affect many organs, including the heart. Cardiovascular disease is a dominant comorbidity and prognostic factors predicting risk for critical courses are highly needed. Moreover, immunomechanisms underlying COVID-induced myocardial damage are poorly understood.

OBJECTIVE

To elucidate prognostic markers to identify patients at risk.

RESULTS

Only patients with pericardial effusion (PE) developed a severe disease course, and those who died could be identified by a high CD8/Treg/monocyte ratio. Ten out of 19 COVID-19 patients presented with PE, 7 (78%) of these had elevated APACHE-II mortality risk-score, requiring mechanical ventilation. At admission, PE patients showed signs of systemic and cardiac inflammation in NMR and impaired cardiac function as detected by transthoracic echocardiography (TTE), whereas parameters of myocardial injury e.g. high sensitive troponin-t (hs-TnT) were not yet increased. During the course of disease, hs-TnT rose in 8 of the PE-patients above 16 ng/l, 7 had to undergo ventilatory therapy and 4 of them died. FACS at admission showed in PE patients elevated frequencies of CD3⁺CD8⁺ T cells among all CD3+ T-cells, and lower frequencies of Tregs and CD14⁺HLA^-DR⁺-monocytes. A high CD8/Treg/monocyte ratio predicted a severe disease course in PE patients, and was associated with high serum levels of antiviral cytokines. By contrast, patients without PE and PE patients with a low CD8/Treg/monocyte ratio neither had to be intubated, nor died.

CONCLUSIONS

PE predicts cardiac injury in COVID-19 patients. Therefore, TTE should be performed at admission. Immunological parameters for dysfunctional antiviral immunity, such as the CD8/Treg/monocyte ratio used here, supports risk assessment by predicting poor prognosis.

[Not Another Arm Vein Thrombosis - Memories of the Past]

Not Another Arm Vein Thrombosis - Memories of the Past Abstract. This article points out relevant differential diagnoses of a unilateral arm swelling that is a key clinical sign of an upper extremity vein thrombosis. The presented case is a patient with a symptomatic, iatrogenic arteriovenous fistula between the subclavian artery and vein due to central venous port system implantation.

Exercise induced leg pain due to endofibrosis of external iliac artery

Due to monotonous movement patterns, muscular hypertrophy, and increased cardiac output peripheral vasculature of athletes are subject to extreme stresses during athletic performance. Individuals suffering from exercise induced non-traumatic lower leg pain may display underlying vascular pathology such as external iliac artery endofibrosis. Therefore, it is essential in the course of to discriminate vascular from non-vascular findings and prime the correct diagnostic path within the course of clinical examination. In this regard, interdisciplinary thinking and profound knowledge in exercise-associated pathologies of the musculoskeletal, nervous and vascular system is indispensable. Consequently, provocation testing displays an indispensable diagnostic tool and has to be continued until symptoms occur, or complete exhaustion is attained. Finally, selective assessment of conservative and surgical treatment options, as well as its ethical evaluation, are of major importance in order to protect, preserve and promote the health and physical integrity of our patients who are keen to perform.

Parameters predicting COVID-19-induced myocardial injury and mortality

Clinical manifestations of COVID-19 affect many organs, including the heart. Cardiovascular disease is a dominant comorbidity and prognostic factors predicting risk for critical courses are highly needed. Moreover, immunomechanisms underlying COVID-induced myocardial damage are poorly understood.

OBJECTIVE

To elucidate prognostic markers to identify patients at risk.

RESULTS

Only patients with pericardial effusion (PE) developed a severe disease course, and those who died could be identified by a high CD8/Treg/monocyte ratio. Ten out of 19 COVID-19 patients presented with PE, 7 (78%) of these had elevated APACHE-II mortality risk-score, requiring mechanical ventilation. At admission, PE patients showed signs of systemic and cardiac inflammation in NMR and impaired cardiac function as detected by transthoracic echocardiography (TTE), whereas parameters of myocardial injury e.g. high sensitive troponin-t (hs-TnT) were not yet increased. During the course of disease, hs-TnT rose in 8 of the PE-patients above 16 ng/l, 7 had to undergo ventilatory therapy and 4 of them died. FACS at admission showed in PE patients elevated frequencies of CD3⁺CD8⁺ T cells among all CD3+ T-cells, and lower frequencies of Tregs and CD14⁺HLA^-DR⁺-monocytes. A high CD8/Treg/monocyte ratio predicted a severe disease course in PE patients, and was associated with high serum levels of antiviral cytokines. By contrast, patients without PE and PE patients with a low CD8/Treg/monocyte ratio neither had to be intubated, nor died.

CONCLUSIONS

PE predicts cardiac injury in COVID-19 patients. Therefore, TTE should be performed at admission. Immunological parameters for dysfunctional antiviral immunity, such as the CD8/Treg/monocyte ratio used here, supports risk assessment by predicting poor prognosis.

Ultrasound-Guided Percutaneous Arterial Puncture and Closure Device Training in a Pulsatile Model

OBJECTIVE

The current study assesses the feasibility of in vitro practice of percutaneous puncture techniques in a pulsatile flow-model.

DESIGN

Prospective, controlled, randomized study.

SETTING

The percutaneous access to endovascular aortic repair is considered safe, but success rates may be dependent on surgeon experience with the technique.

PARTICIPANTS

Fourteen vascular surgery trainees and consultants were enrolled and randomized to a study or control group with both groups receiving instructions by a tutor on how to perform ultrasound guided percutaneous puncture and closure using a suture-mediated closure device. The study group received additional hands-on training on a pulsatile flowmodel of the groin and the performance of both groups was then graded. Study group participants were timed during and after their training on the model.

RESULTS

The study group achieved higher overall grading than the control group on a 5-point scale with higher scores indicating a better performance (mean overall scores 4.0 ± 0.7 versus 2.8 ± 1.0, respectively; p = 0.03). Experienced participants (more than 20 punctures performed before the study) achieved higher overall scores than trainees (3.8 ± 0.4 versus 2.5 ± 0.8, respectively; p = 0.01). Five participants in the study group could deploy and close the ProGlide closure device correctly without the help of a tutor while being graded (71% in the study versus 0% in the control group; p = 0.02). Study group participants improved their overall score from 3.2 ± 0.9 to 4.0 ± 0.7 during training (p = 0.02). Time needed to complete the puncture and closure reduced from 456 seconds on average before, to 302 seconds after training (p < 0.001).

CONCLUSIONS

Study group participants could improve their overall score while working on the simulator. More experienced participants performed better during the simulation, which may indicate the model to be life-like and a potential skills assessment tool. Simulation training may be a valuable adjunct to traditional forms of training when teaching an endovascular technique but is limited by its reliance on simulators and demo devices.

A telemedicine communication exchange network in Gorno-Badakhshan Autonomic Oblast in collaboration with Swiss Surgical Teams

INTRODUCTION

The purpose of this article is to report on the implementation of a telemedicine network serving as a second opinion pool for a surgeon in a remote area of a developing country.

METHODS

This study involved an international collaboration between two members of Swiss Surgical Teams at a tertiary referral hospital and a surgeon in a remote area in Gorno-Badakhshan Autonomic Oblast, Tajikistan, which established a second opinion pool discussing diagnostics and therapeutic options via a messenger application. A retrospective analysis of response times was performed using a series of 50 challenging cases.

RESULTS

The median time to receive a first telemedical response from any of the two contacts was 24 min (interquartile range 6-73). Urgent and emergent pathologies accounted for 57% of cases. The suggested treatment was carried out in 90% (n = 44) of cases.

CONCLUSIONS

Timely and convenient telemedicine support to provide diagnostic and therapeutic reassurance and improve treatment quality for patients presenting to a general and vascular surgeon in the large and remote region of Gorno-Badakhshan Autonomic Oblast can be installed via a messenger application.

Symptomatic type I endoleak following popliteal artery aneurysm repair

A case of a symptomatic type Ib endoleak following popliteal artery aneurysm repair with successful interventional therapy introduces a short review of the limited literature to this relevant potential complication. Illustration of important factors supporting endoleak formation after endovascular popliteal artery repair and recommendation of a consequent surveillance are discussed.

The management of lower limb arteriovenous grafts in the perioperative period following renal transplantation

BACKGROUND

The presence of a lower limb arteriovenous graft (LL-AVG) is indicative of a group of complex hemodialysis patients who have precarious long-term vascular access. The aim of this study is to describe our experience of the clinical decisions and interactions between LL-AVG and renal transplantation.

METHODS

The records of 23 patients who received a transplant in the presence of a LL-AVG between 2010 and 2018 were analyzed: firstly, to determine whether patients with a LL-AVG received extended criteria transplants, the implantation procedure, and the management of the LL-AVG in the post-operative period.

RESULTS

Seventeen patients (74%) had "end-stage access" and were thus considered for all offer stratified by the kidney donor profile index (KDPI) and donor type (DBD or DCD). In eleven patients (48%), a kidney with a high risk of delayed graft function was transplanted. Same-sided renal transplantation occurred in only 35% of cases, and of these, only one LL-AVG was ligated immediately to improve transplant perfusion.

CONCLUSION

A patient-based approach applied in decision-making on management of the LL-AVG post-transplantation should include (a) the likelihood of delayed graft function, (b) the need for post-operative hemodialysis, (c) the side of proposed transplant compared to the LL-AVG, and (d) local complications.

Endoscopic Superficialisation of Haemodialysis Arteriovenous Fistulas in Obese Patients - Safety, Feasibility, and Outcomes

OBJECTIVE

The aim was to evaluate the safety and feasibility of endoscopic superficialisation (ES) in patients with deeply located cephalic veins in well matured arteriovenous fistulae (AVF) and to present functional outcomes.

METHODS

All patients with cannulation difficulties due to a deep lying cephalic vein of more than 6 mm but with an otherwise matured AVF with a straight needle access segment of at least 6 cm were included in this retrospective study. Procedure related safety, defined as completion of ES with no need for conversion to open surgery, and feasibility in terms of cephalic vein depth reduction were assessed. The primary endpoint was three successfully performed haemodialysis sessions using the endoscopically superficialised AVF during a minimum follow up of 12 months.

RESULTS

From June 2013 to August 2017, 12 patients with a mean body mass index of 33.5 ± 3.9 kg/m² underwent ES as a second stage procedure following radiocephalic (n = 5) or brachiocephalic AVF (n = 7) creation. All procedures were conducted endoscopically. Ultrasound imaging 12 weeks post-operatively documented a reduction in the depth of the cephalic vein from a mean of 10.1 ± 1.4 mm to 4.3 ± 0.8 mm. The mean duration of the ES was 69 ± 26.0 min with 67% performed under locoregional anaesthesia. In all but one patient with a cephalic vein of poor wall quality leading to recurrent haematoma, haemodialysis was performed successfully following ES.

CONCLUSIONS

Endoscopic superficialisation of the cephalic vein is a safe and effective technique. Providing good functional results, ES represents an alternative approach for second stage superficialisation in obese patients.

Nectin-4 Expression Is an Independent Prognostic Biomarker and Associated With Better Survival in Triple-Negative Breast Cancer

Background: Triple-negative breast cancer (TNBC) represents about 10-20% of all invasive breast cancers and is associated with a poor prognosis. The nectin cell adhesion protein 4 (Nectin-4) is a junction protein involved in the formation and maintenance of cell junctions. Nectin-4 has previously shown to be expressed in about 60% of TNBC as well as in TNBC metastases, but to be absent in normal breast tissue, which makes it a potential specific target for TNBC therapy. Previous studies have shown an association of Nectin-4 protein expression with worse prognosis in TNBC in a small patient cohort. The aim of our study was to explore the role of Nectin-4 in TNBC and confirm its impact on survival in a larger TNBC patient cohort.

Material and Methods: We performed immunohistochemical staining for Nectin-4 on a tissue microarray encompassing 148 TNBC cases with detailed clinical annotation and outcomes data.

Results: A high expression of Nectin-4 was present in 86 (58%) of the 148 TNBC cases. In multivariate survival analysis, high expression of Nectin-4 was associated with a significantly better overall survival when compared with low expression of Nectin-4 (p < 0.001). Nectin-4-high expression was also significantly associated with a lower tumor stage (p = 0.025) and pN0 lymph node stage (p = 0.034).

Conclusion: Our results confirm that expression of Nectin-4 serves as a potential prognostic marker in TNBC and is associated with a significantly better overall survival. In addition, Nectin-4 represents a potential target in TNBC, and its role in molecular defined breast cancer subtype should be investigated in larger patient cohorts.

Infiltration by myeloperoxidase-positive neutrophils is an independent prognostic factor in breast cancer

PURPOSE

Myeloperoxidase (MPO) is an enzyme secreted by neutrophil granulocytes as a result of phagocytosis during inflammation. In colorectal cancer, tumour infiltration by MPO expressing cells has been shown to be independently associated with a favourable prognosis. In this study, we explored the role of MPO-positive cell infiltration and its prognostic significance in invasive breast cancer.

METHODS

We performed immunohistochemical staining for MPO on multiple tissue microarrays comprising a total of 928 human breast cancer samples with detailed clinical-pathological annotation and outcome data.

RESULTS

MPO-positive cell infiltration (≥ 5 cells/tissue punch) was found in 150 (16%) of the 928 evaluable breast cancer cases. In univariate survival analyses, infiltration by MPO-positive cells was associated with a significantly better overall survival (p < 0.001). In subset univariate analyses, the infiltration by MPO-positive cells was associated with significantly better overall survival in the Luminal B/HER2-negative subtype (p = 0.005), the HER2 enriched subtype (p = 0.011), and the Triple Negative subtype (p < 0.001). In multivariate analysis, MPO expression proved to be an independent prognostic factor for improved overall survival (p < 0.001).

CONCLUSIONS

This is the first study to show that infiltration of MPO-positive cells is an independent prognostic biomarker for improved overall survival in human breast cancer.

Endovascular Retrieval of Intracaval Cement: A Fishing Net Technique

PURPOSE

To describe a novel endovascular technique for intracaval cement retrieval after spinal surgery.

TECHNIQUE

We produced a replica of the intracaval cement fragment and a 3D print to plan the endovascular procedure. A woven caval filter was modified with two drawstring sutures to be used as fishing net. We used a 10F sheath in the right internal jugular vein to place the caval filter proximal to the floating fragment, and a 24F sheath in the right femoral vein was the working access. After the deployment of the caval filter, the following steps were performed through the 24F sheath: (A) The drawstring sutures were snared and retrieved to the skin surface in the groin; (B) the fragment was secured with two snare catheters from the femoral access and one through the lumen of the caval filter; (C) the fragment was broken off with a snared guide wire at the base; (D) the smallest fragment was removed directly with the snare; (E) the larger dislodged fragment was controlled within the periprocedural caval filter by tightening the drawstring and removed through the 24F sheath.

CONCLUSION

Cement fragments located in the inferior vena cava after cement-augmented spinal surgery procedures can be safely removed by the described fishing net technique.

Case report of an intracaval leiomyomatosis 10 months after complete hysterectomy

•

Intravenous leiomyomatosis within the vena cava can spread rapidly as far proximally as intracardially.

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Intravenous leiomyomatosis can be removed bluntly through cavotomy.

•

Sternotomy can be avoided, reducing the surgery to a laparotomy.

Introduction

Intravenous leiomyomatosis (IVL) is a rare smooth muscle tumor, usually found in women with tumors of the reproductive organs, such as uterus myomatosous. Surgically, this case belies the call for sternotomy and two-stage surgery in caval IVL extending to the right atrium: we suggest one-stage median laparotomy as a minimal procedure with maximal benefit.

Presentation of case

We present the case of a 60-year-old postmenopausal woman with suspected intravenous leiomyomatosis of the right internal iliac vein. The patient had undergone hysterectomy and bilateral adnexectomy for uterus myomatosous in September 2015, where an IVL limited to the veins of the uterus and the right adnex had been diagnosed. No further medical treatment had been implemented. IVL of the inferior vena cava was diagnosed when a CT scan of the abdomen was performed due to an infected abdominal seroma in June 2016. Although histologically benign, we found this case of IVL to be clinically aggressive because of its expansion to the heart. This may lead to thromboembolic complications (e.g. pulmonary embolism) or signs of right sided cardiac failure. The patient was asymptomatic, but because of the extension of the intracaval thrombus to the heart, we decided to operate and performed thrombectomy via a median laparotomy. The patient left the hospital shortly after on newly started oral anticoagulation.

Discussion

For caval IVL without intracardiac attachment, the extraction via laparotomy without sternotomy is the treatment of choice. It calls for an interdisciplinary approach and careful surgical planning.

Conclusion

There is no inherent need for sternotomy in IVL extending to the right atrium. A one-year follow-up with sonographic control is advised. Medium term oral anticoagulation should be considered.

This work has been reported in line with the SCARE criteria Agha et al. (2016). The SCARE Statement: Consensus-based surgical case report guidelines. Agha RA, Fowler AJ, Saeta A, Barai I, Rajmohan S, Orgill DP; SCARE Group. Int J Surg. 2016 Oct;34:180-186 [1].

Probiotic helminth administration in relapsing-remitting multiple sclerosis: a phase 1 study

BACKGROUND

Probiotic treatment strategy based on the hygiene hypothesis, such as administration of ova from the non-pathogenic helminth, Trichuris suis, (TSO) has proven safe and effective in autoimmune inflammatory bowel disease.

OBJECTIVE

To study the safety and effects of TSO in a second autoimmune disease, multiple sclerosis (MS), we conducted the phase 1 Helminth-induced Immunomodulatory Therapy (HINT 1) study.

METHODS

Five subjects with newly diagnosed, treatment-naive relapsing-remitting multiple sclerosis (RRMS) were given 2500 TSO orally every 2 weeks for 3 months in a baseline versus treatment control exploratory trial.

RESULTS

The mean number of new gadolinium-enhancing magnetic resonance imaging (MRI) lesions (n-Gd+) fell from 6.6 at baseline to 2.0 at the end of TSO administration, and 2 months after TSO was discontinued, the mean number of n-Gd+ rose to 5.8. No significant adverse effects were observed. In preliminary immunological investigations, increases in the serum level of the cytokines IL-4 and IL-10 were noted in four of the five subjects.

CONCLUSION

TSO was well tolerated in the first human study of this novel probiotic in RRMS, and favorable trends were observed in exploratory MRI and immunological assessments. Further investigations will be required to fully explore the safety, effects, and mechanism of action of this immunomodulatory treatment.