Early and Mid-Term Outcomes of the Inverted Limb Configuration Below Fenestrated and Branched Endografts: Experience from Two European Centers

PURPOSE

To report a European experience on the use of the Inverted Limb (IL) below fenestrated and branched endografts (FB-EVAR) for the treatment of juxta/pararenal (JP-AAAs), thoracoabdominal (TAAAs), and para-anastomotic aortic aneurysms.

MATERIALS AND METHODS

Between 2016 and 2020, all FB-EVAR with distal IL due to previous open (OSR) or endovascular repair (EVAR) or infrarenal aortic length <76 mm at two European university centers were retrospectively analyzed. Technical success, early and mid-term iliac complications (occlusion; type Ib endoleak [EL]), IL-related complications (type III EL), and reinterventions were assessed as primary endpoints; 30-day mortality, survival and freedom from (FF) overall complications/reinterventions were assessed as secondary outcomes.

RESULTS

Forty-one high-risk patients (male 30%-73%; mean age 71±10 years; ASA 3-4, 41%-100%) underwent FB-EVAR with distal IL for 8 (19.5%) J/P-AAAs and 33 (80.5%) TAAAs. Sixteen (39%) patients with previous aortic treatment (8 OR, 8 EVAR) were included. Preoperative computed tomographic angiography showed infrarenal aortic length <76 mm in all cases. Custom-made endografts were configured as 31 (75.6%) fenestrated-only, 6 (14.6%) branched-only, and 4 (9.8%) fenestrated+branched for an overall of 158 target visceral vessels (TVVs; 3.8±0.7 TVVs/case). The IL main body was planned with 1-stent, 2-stents, and 3-stents in 6 (14.6%), 23 (56.1%), and 12 (29.3%) cases, respectively. Technical success and 30-day mortality were 97.6% (40/41) and 0%. Thirty-day complications occurred in 2 (4.9%) patients: 1 limb occlusion, requiring reintervention, 1 type III EL, spontaneously resolved. Mean follow-up was 21±16 months. Three After 30-day, 3 (7.3%) iliac complications (2 occlusions; 1 type Ib EL) were successfully managed by endovascular reinterventions; no IL-related complications were observed. The patency of TVVs was 96.8%. No correlation between anatomical characteristics, endograft configuration, and primary outcomes was observed, except for 1-stent IL and type III EL (log rank p=0.01). At 1- and 2-year follow-up survival, FF overall iliac/IL-related complications and FF reinterventions were 90% and 80%, 90% and 84%, and 92% and 87%, respectively.

CONCLUSION

The IL configuration allows a safe endovascular treatment of challenging aortic lesions in high-risk patients although needing a number of adjunctive procedures. A short main body of IL could be associated with intraoperative and perioperative type III EL.

CLINICAL IMPACT

Bifurcated endograft with inverted limb configuration increases the feasibility of a total endovascular approach in patients with challenging anatomy. The use of inverted limb overcomes the anatomical limitations of short-body initial grafts and short distance between lowest target artery and the aortic bifurcation, leading the fixation inside the endograft. Although technically demanding, this advanced technology could avoid surgical reinterventions in previous open or endovascular repair that are burdened with higher rates of morbidities and complications.

Reinterventions and sac dynamics after fenestrated endovascular aortic repair with physician-modified endografts for index aneurysm repair and following proximal failure of prior endovascular aortic repair

OBJECTIVE

The high frequency of reinterventions after fenestrated endovascular aortic repair (FEVAR) with physician-modified endografts (PMEGs) has been well-studied. However, the impact of prior EVAR on reinterventions and sac behavior following these procedures remains unknown. We analyzed 3-year rates of reinterventions and sac dynamics following PMEG for index aneurysm repair compared with PMEG for prior EVAR with loss of proximal seal.

METHODS

We performed a retrospective analysis of 122 consecutive FEVARs with PMEGs at a tertiary care center submitted to the United States Food and Drug Administration in support of an investigational device exemption trial. We excluded patients with aortic dissection (n = 5), type I to III thoracoabdominal aneurysms (n = 13), non-elective procedures (n = 4), and prior aortic surgery other than EVAR (n = 8), for a final cohort of 92 patients. Patients were divided into those who underwent PMEG for index aneurysm repair (primary FEVAR) and those who underwent PMEG for rescue of prior EVAR with loss of proximal seal (secondary FEVAR). The primary outcomes were freedom from reintervention and sac dynamics (regression as ≥5 mm decrease, expansion as ≥5 mm increase, and stability as <5 mm increase or decrease) at 3 years. Secondary outcomes were perioperative mortality and 3-year survival.

RESULTS

Of the 92 patients included, 56 (61%) underwent primary FEVAR and 36 (39%) underwent secondary FEVAR. Secondary FEVAR patients were older (78 years [interquartile range (IQR), 74.5-83.5 years] vs 73 years [IQR, 69-78.5 years]; P < .001), more frequently male (86% vs 68%; P = .048), and had larger aneurysms (72.5 mm [IQR, 65.5-81 mm] vs 59 mm [IQR, 55-65 mm]; P < .001). Perioperative mortality was 1.8% for primary FEVAR and 2.7% for secondary FEVAR (P = .75). At 3 years, overall survival was 84% for primary FEVAR and 71% for secondary FEVAR (P = .086). Freedom-from reintervention was significantly higher for primary FEVAR than secondary FEVAR, specifically 82% vs 38% at 3 years (P < .001). Primary FEVAR also had more desirable sac dynamics relative to secondary FEVAR at 3 years (primary: 54% stable, 46% regressed, 0% expanded vs secondary: 33% stable, 28% regressed, and 39% expanded; P = .038).

CONCLUSIONS

FEVAR for primary aortic repair and FEVAR for rescue of prior EVAR with loss of proximal seal are two distinct entities. Following primary FEVAR, less than a quarter of patients have undergone reintervention at 3 years, and sac expansion was not seen in our cohort. Comparatively, 3 years after secondary FEVAR, over one-half of patients have undergone reintervention and over one-third have had ongoing sac expansion. Vigilant surveillance and a low threshold for further interventions are crucial following secondary FEVAR.

Outcomes of post-implantation syndrome after endovascular repair for Stanford type B aortic dissection

OBJECTIVE

The aim of this study was to investigate the correlation between post-implantation syndrome (PIS) and long-term prognosis in patients with Stanford type B aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

This retrospective study included 547 consecutive patients diagnosed with TBAD who underwent TEVAR at our institution between January 2014 and December 2019. Patients were categorized into two groups: the PIS group (patients with post-TEVAR PIS) and the non-PIS group (patients without post-TEVAR PIS). In-hospital and follow-up data were analyzed.

RESULTS

The incidence of PIS was 28.9% (158/547 patients). No baseline differences were observed between the PIS (n = 158) and the non-PIS (n = 389) groups. The proportion of emergency surgery in the PIS group was higher than that in the non-PIS group (44.9% vs 26.0%; P < .001), the operation time was longer (median, 65.0; interquartile range [IQR], 56.0-75.0 minutes vs 56.0; IQR, 45.0-66.0 minutes; P < .001), the volume of contrast medium used (median, 65.0; IQR, 56.0-75.0 mL vs 56.0; IQR, 45.0-66.0 mL; P < .001), and the average number of trunk stents (1.85 ± 0.4 vs 1.34 ± 0.5 pieces; P < .001) and branch stents (0.7 ± 0.7 vs 0.2 ± 0.5 pieces; P < .001) used were more in the PIS group than in the non-PIS group. The incidence of supra-aortic branch procedures was higher in the PIS group than in the non-PIS group. There was no significant difference in device-related complications (DRCs) or 30-day mortality between the two groups (2.5% vs 4.4%; P = .442 and 1.3% vs 1.3%; P = .688, respectively). Univariate and multivariable logistic regression analysis showed that emergency surgery, number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL were risk factors for PIS, and the odds ratios of emergency operation, number of trunk stents >1 piece, operation time >58.5 minutes, and contrast medium volume >75 mL were 2.526 (95% confidence interval [CI], 1.530-4.173), 4.651 (95% CI, 2.838-7.624), 3.577 (95% CI, 2.201-5.815), and 7.356 (95% CI, 4.111-13.160), respectively. Follow-up was completed in 98.5% (532/540) of the patients, with a median follow-up of 67 months (IQR, 50-86 months). There was no significant difference in survival between the PIS and non-PIS groups (12.4% vs 10.3%; P = .476) during follow-up. The incidences of DRCs (7.8% vs 11.6%; P = .200) and aortic false lumen thrombosis (75.8% vs 79.2%; P = .399) were comparable between the PIS and non-PIS groups. Univariate logistic regression analysis showed that PIS had no effect on long-term follow-up mortality, DRCs, entry flow, or aortic false lumen thrombosis rate.

CONCLUSIONS

PIS is relatively common after TEVAR and emergency surgery; number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL are of high predictive value for the assessment of PIS after TEVAR. However, PIS had little effect on early and late postoperative mortality or DRCs.

Emergent In Situ Fenestration in the Ascending Aorta for the Endovascular Repair of a Large Pseudoaneurysm: A Technical Note

PURPOSE

The purpose of this article is to describe an emergent in situ fenestration (ISF) technique in the ascending aorta for the endovascular repair of a large pseudoaneurysm using a trans-septal needle device through direct right common carotid artery access, in a patient with left ventricular assist device (LVAD).

TECHNIQUE

We performed, in a multidisciplinary team-work approach, an emergent ISF to correct the displacement of a physician-modified thoracic endograft released in the ascending aorta to correct a large anastomotic pseudoaneurysm in a patient who underwent ascending aorta replacement and subsequent LVAD implantation. We used a trans-septal needle device inserted through a direct access to the right carotid artery and performed an ISF to restore the patency of the outflow ostium of the LVAD. Window was then completed and stabilized with a nitinol balloon expandable covered stent graft obtaining an effective exclusion of the anastomotic aortic aneurism and the regular patency of the LVAD outflow graft with no signs of leaks.

CONCLUSIONS

Multidisciplinary teamwork approach can be crucial in challenging procedures where an alternative approach may lead to problem solving. The ISF technique may be a valid option to adopt in emergency cases in which no other technical solutions are suitable.

CLINICAL IMPACT

The endovascular approach has become more and more frequent for the treatment of vascular pathologies, getting increasingly refined and complex. Thereby the chance of incurring intraprocedural troubles has grown and bailout strategies should always be present. In situ fenestration is a technique to be aware of and that could help you recover from difficult situations. We report a possible rescue maneuver that can be applied also in arduous anatomies such as the ascending aorta. Moreover, we would like to highlight the importance of a multidisciplinary working environment that can enrich our everyday practice accomplishing effective and unexpected solutions.

Pre-emptive Aortic Side Branch Embolization during Endovascular Aneurysm Repair Using the Excluder Stent-Graft System: A Prospective Multicenter study

PURPOSE

To evaluate the effectiveness and safety of pre-emptive transcatheter arterial embolization (P-TAE) for aortic side branches (ASBs) to prevent Type 2 endoleaks (EL2) before endovascular aneurysm repair (EVAR) using the Excluder stent-graft system (Excluder).

MATERIALS AND METHODS

In this prospective, multicenter study, 80 patients (mean age, 79.1 years [SD ± 6.7]; 85.0% were men; mean aneurysmal sac diameter, 48.4 mm [SD ± 7.4]) meeting the eligibility criteria were prospectively enrolled from 9 hospitals. Before EVAR, P-TAE was performed to embolize the patent ASBs originating from the abdominal aortic aneurysm. Contrast-enhanced computed tomography (CT) was performed at 1 month and 6 months after EVAR. The primary endpoint was EL2 incidence at 6 months, and the secondary endpoints were aneurysmal sac diameter changes at 6 and 12 months, P-TAE outcomes, adverse events related to P-TAE, reintervention, and aneurysm-related mortality.

RESULTS

All patients successfully underwent P-TAE without serious. Coil embolization was successful in 81.6% of ASBs. EL2 incidence at 6 months was identified in 18 of 70 (25.7%) patients. Aneurysmal sac diameter shrinkage (≥5 mm) was observed in 30.0% of patients at 6 months and in 40.9% at 12 months. Only 1 patient required reintervention for EL2 within 1 year of EVAR; aneurysm-related deaths were not observed.

CONCLUSIONS

P-TAE for ASBs before EVAR using Excluder is a safe and effective strategy. It aids in achieving early aneurysmal sac shrinkage and reduces EL2 reintervention at 1 year after EVAR.

Safety and Efficacy of Stent-Graft in the Treatment of Aortoiliac Artery Occlusive Disease: A Multicenter Study of Short-Term and Medium-Term Outcomes

BACKGROUND

To evaluate the short-term and mid-term safety and efficacy of stent-graft compared with bare stents for treatment of aortoiliac occlusive disease (AIOD).

METHODS

One hundred eighty three patients diagnosed with AIOD who received stent implantation at 3 vascular centers in north China between January 2019 and December 2021 were enrolled. Patients were divided into those undergoing stent-graft (Group A; n = 67) or bare stent (Group B; n = 116) implantation for retrospective cohort analysis. Efficacy was assessed as surgical success rate and rate of freedom from clinically driven target lesion reintervention at each follow-up time point. Safety was assessed by the rate of perioperative complication, major limb amputation, and aortoiliac artery-related mortality.

RESULTS

There were no preoperative baseline differences between the 2 groups (P > 0.05). The surgical success was 91.04% for Group A, significantly higher than that for Group B (79.31%; P < 0.05). Incidence of perioperative complications was 2.98% for Group A, significantly lower than that for Group B (9.48%, P < 0.05), as was the rate of major limb amputation (A: 1.49% vs. B: 5.17%) and aortoiliac artery-related mortality (A: 1.49% vs. B: 4.31%), although these 2 indicators were not significantly different (P > 0.05). Follow-up rates were 91.8% for the total follow-up time of 3 years. Kaplan-Meier survival curve analysis gave significantly higher 1-year and 2-year freedom from clinically driven target lesion reintervention for Group A (98.51% and 95.52%) than for Group B (95.69% and 89.66%, P < 0.05).

CONCLUSIONS

Stent-graft is more effective and safer than bare stent in the treatment of AIOD.

Physician Made Bovine Pericardial Tube Grafts in Aortic Infection: A European Multicentre Study

OBJECTIVE

This study examines outcome and durability of physician made bovine pericardial tube grafts in aortic infections in all anatomical locations.

METHODS

This was a retrospective and prospective international multicentre study. Peri-operative and long term outcomes of patients undergoing in situ aortic reconstruction for native or graft infections with physician made bovine pericardial tube grafts between January 2008 and December 2020 in four European tertiary referral centres were analysed. The primary endpoint was recurrent aortic infection. Secondary endpoints were persistent infection, aortic re-operation for infection, graft related complications, and death.

RESULTS

One hundred and sixty eight patients (77% male, mean age 67 ± 11 years) were identified: 38 (23%) with native and 130 (77%) with aortic graft infection. The thirty day mortality rate was 15% (n = 26) overall, 11% (n = 4), and 17% (n = 22) for native and aortic graft infections, respectively (p = .45). Median follow up was 26 months (interquartile range [IQR] 10, 51). Estimated survival at one, two, three, and five years was 64%, 60%, 57%, and 50%, and significantly better for native (81%, 77%, 77%, and 69%) than for graft infections (58%, 55%, 51%, and 44%; p = .011). Nine patients (5.3%) had persistent infection and 10 patients (6%) had aortic re-infection after a median of 10 months (IQR 5, 22), resulting in an estimated freedom from re-infection at one, two, three, and five years of 94%, 92%, 90%, and 86%. Estimated freedom from graft complications at one, two, three, and five years was 91%, 89%, 87%, and 87%.

CONCLUSION

This multicentre study demonstrates low re-infection rates when using physician made bovine pericardial tube grafts, comparable to those of other biological grafts. The rate of graft complications, mainly anastomotic aneurysms and stenoses, was low, while graft degeneration was absent. Physician made bovine pericardial tube grafts are an excellent tool for in situ reconstruction in the setting of native aortic infection or aortic graft infection.

Cross-Seal IDE Trial: Prospective, Multicenter, Single-Arm Study of the Cross-Seal Suture-Mediated Vascular Closure Device System

BACKGROUND

An increasing number of interventional procedures require large-sheath technology (>12F) with a favorable outcome with endovascular rather than open surgical access. However, vascular complications are a limitation for the management of these patients. This trial aimed to determine the effectiveness and safety of the Cross-Seal suture-mediated vascular closure device in obtaining hemostasis at the target limb access site following interventional procedures using 8F to 18F procedural sheaths.

METHODS

The Cross-Seal IDE trial (Investigational Device Exemption) was a prospective, single-arm, multicenter study in subjects undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheaths. The primary efficacy end point was time to hemostasis at the target limb access site. The primary safety end point was freedom from major complications of the target limb access site within 30 days post procedure.

RESULTS

A total of 147 subjects were enrolled between August 9, 2019, and March 12, 2020. Transcatheter aortic valve replacement was performed in 53.7% (79/147) and percutaneous endovascular abdominal/thoracic aortic aneurysm repair in 46.3% (68/147) of subjects. The mean sheath ID was 15.5±1.8 mm. The primary effectiveness end point of time to hemostasis was 0.4±1.4 minutes. An adjunctive intervention was required in 9.2% (13/142) of subjects, of which 2.1% (3/142) were surgical and 5.6% (8/142) endovascular. Technical success was achieved in 92.3% (131/142) of subjects. Freedom from major complications of the target limb access site was 94.3% (83/88).

CONCLUSIONS

In selected patients undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheath, Cross-Seal suture-mediated vascular closure device achieved favorable effectiveness and safety in the closure of the large-bore arteriotomy.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03756558.

Mid-term results of a prospective study for aortic dissection with a gutter-plugging chimney stent graft

OBJECTIVES

Our goal was to access early and mid-term outcomes of a gutter-plugging chimney stent graft for treatment of Stanford type B aortic dissections in the clinical trial Prospective Study for Aortic Arch Therapy with stENt-graft for Chimney technology (PATENCY).

METHODS

Between October 2018 and March 2022, patients with Stanford type B aortic dissections were treated with the Longuette chimney stent graft in 26 vascular centres. The efficiency and the incidence of adverse events over 12 months were investigated.

RESULTS

A total of 150 patients were included. The technical success rate was 99.33% (149/150). The incidence of immediate postoperative endoleak was 5.33% (8/150, type I, n = 6; type II, n = 1; type IV, n = 1) neurologic complications (stroke or spinal cord ischaemia); the 30-day mortality was 0.67% (1/150) and 1.33% (2/150), respectively. During the follow-up period, the median follow-up time was 11.67 (5-16) months. The patent rate of the Longuette graft was 97.87%. Two patients with type I endoleak underwent reintervention. The follow-up rate of the incidence of retrograde A type aortic dissection was 0.67% (1/150). There was no paraplegia, left arm ischaemia or stent migration.

CONCLUSIONS

For revascularization of the left subclavian artery, the Longuette chimney stent graft can provide an easily manipulated, safe and effective endovascular treatment. It should be considered a more efficient technique to prevent type Ia endoleak. Longer follow-up and a larger cohort are needed to validate these results.

CLINICAL TRIAL REGISTRY NUMBER

NCT03767777.

Apico-aortic conduit: a readily available technical modification

When neither surgical valve replacement nor transcatheter aortic valve implantation is possible, performing an apico-aortic conduit remains a therapeutic option. This procedure has become rare and the rigid angled apical connectors usually used to facilitate ventricular anastomosis are no longer commercially available. We described the technique that we performed on a 60-year-old patient with readily available material.

Clinical Impact and Determinants of Fenestration to Target Vessel Misalignment in Fenestrated Endovascular Aortic Repair

OBJECTIVE

This single centre, retrospective study (2014 - 2022) on juxta-, pararenal, or thoraco-abdominal aortic aneurysms treated by fenestrated endovascular aortic repair (FEVAR) was conducted to investigate the clinical impact and determinants of fenestration to target vessel misalignment in FEVAR.

METHODS

Pre-operative supracoeliac, pararenal, and infrarenal aortic angles were measured on three dimensional computed tomography angiography (CTA) reconstructions. Two components of misalignment were measured on the first post-operative CTA: horizontal misalignment (angle between the fenestration and the target vessel ostium on perpendicular CTA cuts) and vertical misalignment (vertical distance between the fenestration and the target vessel at its origin). Endpoints were freedom from target vessel instability (TVI) and alignment change over time.

RESULTS

Of 65 patients treated by FEVAR, 60 (202 target arteries) with juxta-, pararenal (80%), or thoraco-abdominal aortic aneurysm (20%) were included. Mean horizontal misalignment was 9 ± 12° (median 5°; IQR 0 - 16) and mean vertical misalignment was 0.7 ± 1 mm (median 0 mm, IQR 0 - 1). Freedom from TVI was 92% (95% CI 88 - 98) at 36 months. Horizontal misalignment > 15° was significantly associated with TVI (HR 5.19; 95% CI 1.54 - 17.48; p = .008); vertical misalignment did not significantly impact TVI (HR 0.99; 95% CI 0.56 - 1.73; p = .97). By multivariable analysis, pararenal aortic angle (OR 1.01 per increased degree of angulation; 95% CI 1.00 - 1.02; p = .044), bridging distance > 5 mm (OR 1.07; 95% CI 1.02 - 1.11; p = .003), and use of higher profile endografts in tortuous iliac access (OR 7.55; 95% CI 4.55 - 1.11; p = .003) were associated with clinically significant misalignment. Bridging distance > 5 mm (OR 2.00; 95% CI 1.02 - 11.29; p = .044), degree of baseline misalignment (OR 1.04; 95% CI 1.01 - 1.08; p = .036), and persistence of any primary endoleak for > 6 months (OR 5.85; 95% CI 1.23 - 29.1; p = .023) were associated with misalignment increase during follow up.

CONCLUSION

Horizontal misalignment > 15° is associated with worsened target vessel outcomes. This may occur as a result of excessive iliac access tortuosity, high pararenal aortic angulation, and bridging distance > 5 mm.

Endovascular Management of Post-Irradiated Carotid Blowout Syndrome in Patients with Lower Neck Cancers

OBJECTIVE

Lower neck cancers (LNCs) include specific tumour types and have some different vascular supply or collaterals from other head and neck cancers. This prospective study evaluated the outcome of endovascular management of post-irradiated carotid blowout syndrome (PCBS) in patients with LNC by comparing reconstructive management (RE) and deconstructive management (DE).

METHODS

This was a single centre, prospective cohort study. Patients with LNC complicated by PCBS between 2015 and 2021 were enrolled for RE or DE. RE was performed by stent graft placement covering the pathological lesion and preventive external carotid artery (ECA) embolisation without balloon test occlusion (BTO). DE was performed after successful BTO by permanent coil or adhesive agent embolisation of the internal carotid artery (ICA) and ECA to common carotid artery, or ICA occlusion alone if the pathological lesion was ICA only. Cross occlusion included the proximal and distal ends of the pathological lesion in all patients. Re-bleeding events, haemostatic period, and neurological complications were evaluated.

RESULTS

Fifty-nine patients (mean age 58.5 years; 56 male) were enrolled, including 28 patients undergoing RE and 31 patients undergoing DE. Three patients originally grouped to DE were transferred to RE owing to failed BTO. The results of RE vs. DE were as follows: rebleeding events, 13/28 (46%) vs. 10/31 (32%) (p = .27); haemostatic period, 9.4 ± 14.0 months vs. 14.2 ± 27.8 months (p = .59); neurological complication, 4/28 (14%) vs. 5/31 (16%) (p = .84); and survival time, 11.8 ± 14.6 months vs. 15.1 ± 27.5 months (p = .61).

CONCLUSION

No difference in rebleeding risk or neurological complications was observed between the DE and RE groups. RE could be used as a potential routine treatment for PCBS in patients with LNC.

Hemodialysis vascular access flow measurements by the novel DMed NephroFlow® device: A comparative study with Transonic®

INTRODUCTION

The current Spanish Clinical Guidelines on Vascular Access for Hemodialysis support the need for surveillance and monitoring of vascular access (VA) to avoid complications. Ultrasound dilution (UD) methods are accepted for the evaluation of VA flow and Transonic® has established the gold standard method for the measurement. The DMed NephroFlow (NIPRO®) device, based on UD method has recently been incorporated. We report a comparative study between the classic Transonic® versus the new NephroFlow® device.

MATERIAL AND METHODS

For two consecutive months, measurements of VA flow using both referred systems were performed in patients with a native arteriovenous fistula (AVF) or a graft (AVG) on hemodialysis (HD) in our unit. Both studies were undertaken according to the usual recommendations: VA flow of 250 ml/min, ultrafiltration rate without modifications, both needles in the same vein, and always in the first hour of the HD session.

RESULTS

Forty-five patients were included: 17 women and 28 men, mean age of 67 ± 12 years. Thirty patients were diabetic. The baseline meantime on HD was 51 ± 39 months (range: 3-163). Type of VA was: 17 patients radio-cephalic AVF, 17 brachiocephalic AVF, 7 brachiobasilic AVF, and 3 with a graft. The mean flow estimated by the Transonic® was 1222 ± 805 ml/min and the estimated flow by the NephroFlow® device was 1252 ± 975 ml/min. Good reliability between Transonic® and NephroFlow® was observed, with a reliability index of Cronbach's Alpha of 0.927 and an Intraclass Correlation Index of 0.928.

CONCLUSIONS

The NephroFlow® device seems comparable with the accepted gold standard UD method for estimating VA flow. More studies must be performed to verify these results. However, they should be considered for the surveillance and monitoring of VA flow, in agreement with the Spanish Guidelines.

Long term outcomes of 'Christmas Tree' banding for haemodialysis access induced distal ischemia: A 13-year experience

BACKGROUND

The reduction in distal arterial flow following arteriovenous fistula (AVF) creation can cause a perfusion deficit known as haemodialysis access induced distal ischemia (HAIDI). Various techniques have been advocated to treat this difficult problem with varying success. We present the long-term outcomes following a novel banding technique.

METHODS

46 patients in this cohort from 2008 to 2021 underwent a novel banding procedure using a Dacron™ patch shaped with one slit-end and saw-tooth edges (resulting in a 'Christmas-tree' pattern) to provide a ratchet mechanism to progressively constrict the fistula outflow. Real-time finger perfusion pressure monitoring allowed an accurate reduction in AVF flow whilst increasing distal arterial perfusion pressure. Baseline characteristic were recorded and Kaplan-Meier survival curves were obtained to calculate the post-intervention primary, assisted primary and secondary patency.

RESULTS

29 patients presented with rest pain and 11 presented with tissue loss due to distal ischemia. The post-intervention primary access patency was 100%, 98%, 78% and 61% at 30, 60 and 180 days and 1 year respectively. Complete resolution of symptoms was achieved in 74% (n = 34) of patients and a partial response needing no further intervention was achieved in 11% (n = 5) of patients. A Youden index calculation suggested that digital pressures of 41 mm Hg or lower in an open AVF were highly sensitive for symptomatic hand ischemia whereas pressures greater than 65 mm Hg ruled out distal ischemia.

CONCLUSION

'Christmas-tree' banding with on table finger systolic pressures is not only an efficacious and durable method for treating HAIDI but also preserves fistula patency.

Disappointing results of popliteal aneurysm endovascular treatment with a new self-expandable covered stent

PURPOSE

To describe our clinical experience of endovascular exclusion of popliteal artery aneurysms using the new self-expandable covered stent SOLARIS® (Scitech Medical, Brazil), and to report its results in the context of surgical and endovascular treatment of popliteal artery aneurysms.

CASE REPORT

Among 20 popliteal artery aneurysms undergoing open or endovascular repair in 2022 and 2023, two patients were successfully treated with the Solaris stentgraft. Both patients had a patent popliteal artery and three run-off vessels. After stentgraft implantation, they received dual antiplatelet therapy for three months and they were followed-up with Duplex scan and clinical evaluation after three months, and every six months thereafter. After three months, one Solaris stentgraft had complete thrombosis and the other ruptured, requiring surgical removal. No complications were observed among the other aneurysms treated with open repair or with the Viabahn® stentgraft.

CONCLUSIONS

Endovascular treatment of popliteal aneurysms with the new covered self-expandable stent Solaris resulted in severe complications in the two cases reported, and in worse short-term outcomes than endovascular repair with Viabahn® and open repair. Its off-label use to treat popliteal artery aneurysms should be therefore discouraged.

Cost-effectiveness analysis of autogenous arteriovenous fistula, arteriovenous graft, and tunneled-cuffed catheter for hemodialysis in patients with end-stage kidney disease in Southern China

OBJECTIVES

To evaluate the cost-effectiveness of three permanent vascular accesses for maintenance hemodialysis patients from a hospital perspective throughout 5 years, which is the average life expectancy of patients with end-stage kidney disease.

SUBJECTS AND METHODS

We conducted a EuroQol(EQ-5D) questionnaire survey between January 2021 and March 2021 with 250 patients to estimate the health utility of various states in patients under different hemodialysis vascular access. We designed a Markov model and conducted a cost-effectiveness analysis to compare the cost-effectiveness of three hemodialysis vascular access in Guangzhou throughout 5 years.

RESULTS

The mean costs were US$44,481 with tunneled-cuffed catheter (TCC), and US$68,952 and US$59,247 with arteriovenous graft (AVG) and autogenous arteriovenous fistula (AVF), respectively. The mean quality-adjusted life-years (QALYs) was 1.41 with TCC, and 2.37 and 2.73 with AVG and AVF, respectively. AVG had an incremental cost-effectiveness ratio (ICER) of US$25,491 per QALY over TCC; AVF had an ICER of -US$26,958 per QALY over AVG. At a willingness to pay below US$10,633.8 per QALY, TCC is likely the most cost-effective vascular access. At any willingness to pay between US$10,633.8 and US$30,901.4 per QALY, AVF is likely the most cost-effective vascular access.

CONCLUSION

These findings illustrate the value of AVF given its relative cost-effectiveness to other hemodialysis modalities. Although AVG costs much more than TCC for slightly higher QALYs than TCC, AVG still has a greater advantage over TCC for patients with longer life expectancy due to its lower probability of death.

Periadventitial biomaterials to improve arteriovenous fistula and graft outcomes

Periadventitial biomaterials have been employed for nearly three decades to promote adaptive venous remodeling following hemodialysis vascular access creation in preclinical models and clinical trials. These systems are predicated on the combination of scaffolds, hydrogels, and/or particles with therapeutics (small molecules, proteins, genes, and cells) to prevent venous stenosis and subsequent maturation failure. Periadventitial biomaterial therapies have evolved from simple drug delivery vehicles for traditional drugs to more thoughtful designs tailored to the pathophysiology of access failure. The emergence of tissue engineering strategies and gene therapies are another exciting new direction. Despite favorable results in experimental and preclinical studies, no periadventitial therapy has been clinically approved to improve vascular access outcomes. After conducting an exhaustive review of the literature, we identify the seminal studies and clinical trials that utilize periadventitial biomaterials and discuss the key features of each biomaterial format and their respective shortcomings as they pertain to access maturation. This review provides a foundation from which clinicians, surgeons, biologists, and engineers can refer to and will hopefully inspire thoughtful, translatable treatments to finally address access failure.

The usefulness of staged extra-anatomic bypass for coarctation of the aorta with arch hypoplasia, from premature neonate to adult

Various surgical techniques have been developed for coarctation of the aorta. However, coarctation repair in neonates with arch hypoplasia remains challenging. We herein report a case in which a premature neonate under 1500 g with coarctation of the aorta and arch hypoplasia underwent an extra-anatomical bypass at 18 days old. A second extra-anatomical bypass was performed at 3 years of age, and a third extra-anatomic bypass for recurrent coarctation was performed in adulthood. By increasing the size of the graft as the patient grows, extra-anatomic bypass can be a useful surgical option for premature neonates with coarctation and arch hypoplasia.