Comparing post-maturation outcomes of arteriovenous grafts and fistulae

BACKGROUND

Though arteriovenous grafts (AVG) mature more reliably than arteriovenous fistulae (AVF) and require fewer maturation procedures (MP) to obtain functional patency, AVG are thought to have worse function after maturation. We explored differences in post-maturation outcomes between the following groups: AVF patients who did (AS-AVF) and did not (unAS-AVF) require assisted maturation and AVG patients who did (AS-AVG) and did not (unAS-AVG) require assisted maturation.

METHODS

Using the US Renal Data System (2012-2017), we retrospectively identified patients who initiated dialysis with a central venous catheter, underwent AVF or AVG placement and achieved successful two-needle cannulation. Primary patency and access abandonment after maturation were compared across groups using competing risks regression methods, generating sub-hazards ratios (sHR).

RESULTS

We identified 42,664 AVF and 12,335 AVG that met inclusion criteria. A larger proportion of AVFs required interventions: 18,408 AVF (43.2%) versus 2594 AVG (21.0%; p < 0.01). Both AS-AVG and AS-AVF patients experienced patency loss at 1 year more frequently compared with unAS-AVG (67.5% & 57.5% vs 55.2% respectively). Patency loss was lowest in unAS-AVF (38.9%). These trends were robust on adjusted analysis (unAS-AVG reference, AS-AVG sHR = 1.44, p < 0.01; AS-AVF sHR = 1.08, p < 0.01, unAS-AVF sHR = 0.67, p < 0.01). AS-AVGs were more likely to be abandoned than unAS-AVGs (11.7% unAS-AVG vs 17.2% AS-AVG). Fistulae, assisted or not, had lower unadjusted rates of 1-year abandonment than grafts (8.9% AS-AVF vs 7.3% unAS-AVF). On adjusted analysis, AVF usage was protective against abandonment (unAS-AVG, reference; AS-AVF sHR = 0.67, p < 0.01; unAS-AVF sHR = 0.59, p < 0.01) while AS-AVG was not (AS-AVG sHR = 1.32, p < 0.01).

CONCLUSIONS

unAS-AVF have the best long-term outcomes. AS-AVF lose primary patency at a higher rate than unAS-AVG. AVGs may be a better choice than AVFs if veins are marginal and likely to require assisted maturation. Further research is needed to identify anatomic and physiologic factors that affect long-term performance and influence conduit choice.

The impact of stent-graft sizing on venous stenosis re-intervention and arteriovenous graft patency: Free-floating stent outflow is associated with improved outcomes

BACKGROUND

Early cannulation arteriovenous grafts (ecAVG) for dialysis access are limited by reintervention for venous stenosis (VS) despite their good initial patency. Whilst stent-grafts (SG) have shown promise, the optimal sizing is unclear. Therefore, this study aims to determine if outflow vein diameter, SG diameter or these relative to each other (V:Sr) alters outcomes, and if so, which is more important.

METHODS

Retrospective analysis was performed of Gore® Acuseal® ecAVGs with VS treated with Gore® Viabahn® SG over a 7-year period. Primary patency (PP), time to thrombosis and functional patency were analysed by SG length/diameter, vein diameter and V:Sr.

RESULTS

We identified 114 ecAVGs with median follow-up 492 days (IQR 189-770). SG length and diameter did not correlate with PP, however, there was a significant relationship between vein diameter and PP (RR = 0.901 (0.832-0.975), p = 0.01) and between V:Sr and PP (RR = 0.462 (0.255-0.838), x2 = 5.866, p = 0.0015). The optimal V:Sr was ⩾1.4 (i.e. vein diameter at least 40% greater than the stent-graft; or 'free-floating' stent outflow) (RR = 2.759 (1.670-4.558), p < 0.001), translating to a difference in median PP of 252 versus 496 days (IQR: 188-316; 322-670). On multivariate analysis, absolute vein diameter lost significance, whilst V:Sr remained an independently significant predictor of PP (RR = 3.247 (1.560-6.759), p = 0.02).

CONCLUSIONS

Placement of the SG outflow into a relatively larger segment of vein was associated with a significant increase in PP independent of the absolute vein diameter. This suggests that larger calibre SG which are apposed to the vein wall are not required for optimal primary patency, and indeed should be actively avoided. Instead, a 'free-floating' stent outflow which is undersized relative to the recipient vein (whilst maintaining a minimum anchoring calibre) is recommended where possible. This should be considered during intervention and may require selection of longer devices, where practical, to bring the stent outflow into a larger vein segment.

LEVEL OF EVIDENCE

Level 3a, Non-randomised controlled cohort/follow-up study.

Delamination of Acuseal arteriovenous graft: Two case reports

Acuseal arteriovenous graft is an early cannulation graft having a tri-layered structure with an elastomeric middle layer. However, delamination of Acuseal grafts has been reported recently. This article describes two cases with different characteristics of Acuseal delamination. In case 1, the delamination occurred 1 month after a percutaneous transluminal angioplasty (PTA); therefore, the PTA was suspected to be a trigger. The delamination was located between the outer expanded polytetrafluoroethylene (ePTFE) layer and the elastomeric middle layer. On the other hand, in case 2, the delamination was located between the luminal ePTFE layer and the elastomeric middle layer. A surveillance ultrasound examination detected the delamination unexpectedly in the uneventful course; however, the delaminating location corresponded to the cannulation puncture site and the intraoperative findings suggested the involvement of mis-needling as a possible cause. Interestingly, for the purpose of continued use on hemodialysis, specific treatments were required against the delamination itself in both cases. As we identified Acuseal delamination in 5.6% (2/36) of cases, concerns arise that numerous cases of Acuseal delamination may have been overlooked in general. Understanding and recognizing this phenomenon are important for adequate use of Acuseal graft.

Effects of Long Term Fatigue Cycling on In Situ Fenestrations of Polyethylene Terephthalate and Expanded Polytetrafluorethylene Thoracic Aortic Stent grafts: An Experimental Study

OBJECTIVE

In this study, the long term durability of fenestrations after in situ fenestration (ISF) of five commercial thoracic aortic stent grafts was evaluated in an in vitro experiment after a simulated 10 year period.

METHODS

Five different thoracic aortic stent grafts (Relay, Valiant, Hercules, TAG, and Ankura, with a diameter of 34 mm) received both needle and laser ISF in vitro. A Viabahn (11 × 50 mm) was released in each fenestration as a bridging stent graft. Long term fatigue tests (simulating 10 years) of each of the fenestrated stent grafts were then conducted in a flow fatigue test system. The area, shape, margin, and the long and short axis of all the fenestrations were evaluated with light microscopy before and after the fatigue test. The leakage from the fenestration junction before and after the long term fatigue was also measured.

RESULTS

The experimental results showed no obvious difference between needle and laser fenestrations. The long axes of all the fenestrations remained unchanged, while the short axes increased after the fatigue test, which was significant in Relay, Valiant, and Hercules polyethylene terephthalate stent grafts. The shape scores of fenestrations improved after the fatigue test in Valiant and Hercules, remained unchanged in Relay and Ankura, and worsened in the TAG. After the fatigue cycling, the average leakage from the fenestration junction decreased in all the stent grafts, and the Ankura had the maximum decline rate.

CONCLUSION

The ISF technique was durable over a simulated 10 year period. The fenestrations were positively remodelled to be more circular, and the leakage from the junction decreased after long term fatigue testing.

A scoping review on surgical reduction of high flow arteriovenous haemodialysis access

Volume flow (Qa) > 1.5-2 l /minQa in arteriovenous accesses may be associated with high flow related systemic or locoregional complications. A variety of surgical techniques are advocated for Qa reduction. Aim of this scoping review is to provide an overview of available evidence regarding the efficacy of this broad spectrum of interventions for Qa reduction in patients with a high flow haemodialysis access. PubMed and Embase were searched according to PRISMA-guidelines. Studies on invasive management of HFA were selected. Inclusion required an English description of surgical techniques in human HFAs including pre- and postoperative access flow-values. Sixty-six studies on 940 patients (mean age 56 years (3-90 years), male 62%, diabetes mellitus 26%, brachial artery-based arteriovenous access 65%) fulfilled inclusion criteria. Performed techniques were banding (58%), revision using distal inflow (12%), plication/anastomoplasty (10%), graft interposition (5%), proximal radial artery ligation (3%), aneurysm repair (4%), or miscellaneous other techniques (8%). Definition of HFA, work-up, indication for surgery and intraoperative monitoring were diverse. All techniques reduced Qa on the short term (mean drop 0.9-1.7 l/min). Secondary access patency rates varied between 70% and 93% (mean follow-up 15 (0-189) months). Definitions of success and recurrence varied widely precluding a comparison of efficacy of techniques. Patient specific factors legitimizing invasive treatment for HFA are discussed. Recommendations on reporting standards when dealing with HFA surgery are provided. In conclusion, the present report on the current management of high flow access does not allow for drawing any definite conclusions due to a lack of standardization in definition, indications for surgical intervention and techniques. Randomized trials comparing different Qa reducing techniques in symptomatic patients are warranted, as are trials comparing a wait-and-see approach versus Qa reduction in asymptomatic patients. As an overview of the variety of techniques was lacking, this scoping review might serve as a map for future researchers.

Outcomes of stent grafts for treatment of central venous disease in hemodialysis patients

BACKGROUND

To evaluate the effectiveness of stent graft (SG) for the treatment of central venous disease (CVD) in hemodialysis patients.

METHODS

Between January 2014 and April 2022, 122 patients on hemodialysis with symptomatic CVD were treated with percutaneous transluminal angioplasty (PTA) and bare-metal stent (BMS) or SG placement. The mean follow-up was 14.5 months (IQR: 8.0, 24.2). Patency rates of the target sites were calculated using Kaplan-Meier and log-rank studies. Multivariate Cox proportional hazard models were used to evaluate the association between various characteristics and target site primary patency.

RESULTS

Technical success rate was 100%. At 3, 6, 12, and 24 months, the target sites primary patency rates were 86.4%, 74.2%, 45.1%, and 30.4% for PTA; 94.7%, 78.6%, 60.8%, and 45.6% for BMS; and 94.0%, 92.0%, 82.4%, and 66.8% for SG, respectively, and the assisted primary patency rates were 86.5%, 80.4%, 63.8%, and 46.0% for PTA; 94.7%, 89.5%, 77.5%, and 71.1% for BMS; 100%, 100%, 97.8%, and 83.4% for SG, respectively. The Kaplan-Meier analysis indicated that SGs achieved better primary and assisted primary patency than PTA or BMS (p<0.05). SG use and concomitant stenosis were the independent predictors of target site primary patency dysfunction in the multivariate analysis.

CONCLUSIONS

This study confirmed the better long-term patency of SG in comparison with PTA and BMS for the treatment of CVD in hemodialysis patients.

Novel insights into thoracic endografts technology for prevention of distal stent-graft induced new entry (dSINE) following endovascular repair of type B aortic dissections: from bench to bedside

INTRODUCTION

Endovascular treatment of type B aortic dissections (TBAD) has currently acquired a primary therapeutic role when anatomically feasible. The main issue with thoracic endovascular aortic repair (TEVAR) for aortic dissection is the actual nature of the aortic wall, which is structurally compromised and more fragile. Indeed, a wealth of data have shown that TEVAR for TBAD will lead, in a substantial proportion of cases, to a device-related adverse event named distal stent-graft induced new entry (dSINE).

AREAS COVERED

Currently available aortic stent-grafts have not been specifically devised for the treatment of aortic dissection. A novel dissection specific stent-graft (DSSG) was developed, which is a custom-made device based on the Zenith Alpha Thoracic platform (Cook Medical). The DSSG has several unique properties that, in principle, make its use optimal in TBAD patients.

EXPERT OPINION

TEVAR in the setting of aortic dissections remains technically challenging. The occurrence of dSINE represents a unique complication in this scenario and may lead to high rates of aortic-related adverse events and need for secondary interventions. The use of a novel custom-made DSSG in the setting of chronic TBAD has been proven to be safe, feasible and effective. However, even this approach may fail to completely prevent dSINE formation.

Straight lateral thigh femoropopliteal-femoral arteriovenous graft an alternative vascular access for patients with exhausted upper limbs dialysis access

INTRODUCTION

The durability of hemodialysis vascular access remains a troublesome issue for the patients as well as vascular surgeons that requires frequent reinterventions to maintain the access function.

AIM

This study aimed to evaluate straight thigh polytetrafluethylene (PTFE) arteriovenous graft (AVG) in patients with exhausted upper extremities dialysis access.

METHOD

Our study was a retrospective analysis of prospectively collected data of 30 patients were operated upon for straight pattern lateral thigh PTFE AVG between 2016 and 2018. The primary outcome was efficacy and patency of AVG, and secondary outcome was procedure safety, including infection, thrombosis, ligation, lower limb functional status, and mortality.

RESULTS

A 30 patients with 30 Lower Limb AVG with maximum 30-month follow-up period. The mean age was 48 years. Males were (n = 15/30). Thrombophilia patients were (n = 7/30). Primary patency at 6 months was 100%. It declined to 93% at 12 months, 73% at 18 months, 47% at 24 months, and 40% at 30 months. The secondary patency was 97% at 18 months, 83% at 24 months, and 73% at 30 months. More than half of the patients showed complications (n = 18/30), the most frequent was thrombosis (n = 16/18). A secondary procedure was needed for 17 patients, the most frequent was thrombectomy (n = 11/17), adjunctive culprit lesion repair was the key for regaining graft patency. Graft removal was necessary in six patients due to infection (n = 4) and ruptured graft aneurysm (n = 2).

CONCLUSION

Lateral straight thigh PTFE AVG is a reliable and durable alternative modality with adequate dialysis efficacy in patients with exhausted upper extremities dialysis accesses. Secondary procedures due to complications were frequent but no significant major bleeding as regard patients with ruptured graft were non-significant and no distal threatening ischemia or related deaths were observed.

Long-term outcomes following thrombolysis of arteriovenous grafts

BACKGROUND

Thrombolysis for arteriovenous grafts (AVG) yields high technical success rates, however, long-term outcomes are unclear. We conducted a multicenter retrospective cohort study to analyze 5-year patency rates following AVG thrombolysis.

METHODS

All patients who underwent AVG thrombolysis between 2005 and 2015 at three academic hospitals were included. Prospectively maintained institutional nephrology and radiology databases were used to record demographic, clinical, and AVG characteristics. The primary outcome was primary patency, defined as AVG access survival without re-intervention including angioplasty ± stent with/without re-thrombolysis. Secondary outcomes were assisted primary patency and cumulative patency, defined as AVG access survival until re-thrombosis requiring re-thrombolysis or abandonment, respectively. Technical success was defined as restoration of flow with <30% residual stenosis. Patients were followed until 2017. Patency rates were assessed using Kaplan-Meier survival analysis and Cox proportional hazards were calculated to determine associations between covariates and patency loss.

RESULTS

Seventy-four patients underwent AVG thrombolysis during the study period with a median follow-up period of 21.4 (IQR 8.3-42.8) months. The average age was 58.6 years with a high rate of comorbidities, including hypertension (82.4%) and diabetes (54.1%). Thrombolysis technical success was 96%. There were 147 re-interventions in 46 patients, of which 98 were re-thrombolysis (mean re-intervention rate of 1.27/patient/year). Primary patency at 1, 3, and 5 years were 43.2%, 20.2%, and 7.7%. Assisted primary patency at 1, 3, and 5 years were 47.5%, 20.2%, and 7.7%. Cumulative patency at 1, 3, and 5 years were 75.0%, 38.8%, and 22.6%. Cox proportional hazards analysis demonstrated no associations between demographic, clinical, and procedural characteristics and patency rates.

CONCLUSIONS

Despite a high technical success rate, thrombolysis for AVG dysfunction is associated with poor long-term patency. Future studies are needed to determine risk factors for re-thrombosis to identify patients who will benefit from AVG thrombolysis in the long-term.

A Single Centre Long Term Follow Up of the Nellix Endovascular Aneurysm Sealing System

OBJECTIVE

To evaluate the clinical performance at long term follow up of endovascular aneurysm sealing (EVAS, Endologix Inc. Nellix, Irvine, CA, USA) in the treatment of abdominal aortic aneurysm (AAA).

METHODS

Observational, prospective, single centre study of primary AAA interventions with EVAS (n = 117) from November 2013 to November 2016. Endpoints were primary technical success, Nellix device failure, freedom from open surgical conversion (OSC), freedom from secondary intervention, sac rupture, total mortality, and aneurysm related mortality at long term follow up.

RESULTS

The median age was 75 years (interquartile range [IQR] 70, 81 years) and 83% were male. The median AAA diameter was 58 mm (IQR 54, 60 mm). The median length of follow up was 6.2 years (IQR 5.6, 6.8 years). Primary technical success was 100%. Median time to Nellix failure was 5.6 years (IQR 3.3, 7.4 years). Freedom from Nellix failure at five and seven years was 54% (95% confidence interval [CI] 54.2 - 63.8%) and 36% (95% CI 22.3 - 49.7%), respectively. Freedom from OSC at five and seven years was 63% (95% CI 53.2 - 72.8%) and 59% (95% CI 47 - 71%), respectively. The secondary intervention rate was 11.4/100 person years. Freedom from secondary intervention at five and seven years was 52% (95% CI 42.2 - 61.8%) and 51% (95% CI 41.2 - 60.8%), respectively. The cumulative mortality rate at five and seven years was 36% and 54%, respectively. Secondary sac rupture occurred in 9.4% (11/117) with a rate of 2/100 person years. Aneurysm related mortality was 12% (14/117) with a rate of 2.5/100 person years. The median survival was four years (IQR 3, 5.6 years). Thirty day mortality for acute OSC was 67% (n = 3) and 17.1% (6/35) for elective OSC.

CONCLUSION

Long term follow up showed an increased failure rate. Diligent surveillance after endovascular AAA treatment is mandatory, especially when promising new devices are put into clinical use.

Two-year follow-up after treatment of an aortic transection in the presence of an aberrant right subclavian artery

OBJECTIVES

An aberrant right subclavian artery (ARSA) is one of the most common anatomic variants of the aortic arch. The combination of an ARSA and a transection is naturally rare.

METHODS

This case report describes the treatment of a transection in the presence of an ARSA and the follow-up of two years.

RESULTS

We successfully treated the contained rupture with a stentgraft. Both subclavian arteries had to be covered in the emergency setting. At the two-year follow-up, the patient did not suffer from any neurological impairment.

CONCLUSIONS

In emergency settings, primary cover of both subclavian arteries with a stentgraft can be performed in individual cases after risk assessment. Severe complications such as development of upper limb ischaemia, ASAS or reduced perfusion of the posterior cerebral circulation should be considered in treatment planning.

Current perspectives in acute type B aortic dissections: a literature review

In this new millennial, endovascular strategies have revolutionized the treatment of acute type B aortic dissection (aTBAD). With reduced in-hospital mortality and good long-term outcomes TEVAR has become the gold standard for the treatment of complicated dissection and is gaining increasing support for its preventive applicability in some uncomplicated dissections. With this new paradigm came a shift of the treatment goal where just covering the entry tear is not enough and instead achieving long-term positive thoracoabdominal remodeling is needed. More extensive approaches with composite device designs (covered stent graft and bare metal stent) emerged to answer this aortic conundrum. At 5-year of follow-up, "Provisional ExTension To Induce COmplete Attachment technique" (PETTICOAT) and its evolution "Stent assisted balloon induced intimal disruption and relamination in aortic dissection repair" (STABILISE) seem to be safe techniques that can allow, when anatomically feasible, excellent aortic remodeling and, in some cases, even the healing of the dissection. Nevertheless, STABILISE results, although promising, are mostly based on small series and therefore need to be validated by analyzing medium-long-term results from the international registry. Given the plethora of new data and the disparity of expert opinions on the best treatment to adopt, in this review we aim to summarize the current knowledge on the results of these different strategies for acute TBAD.

Temporizing stent graft for aortoenteric fistula with massive gastrointestinal hemorrhage

OBJECTIVES

We present a case of a 59-year-old male with an actively bleeding aortoenteric fistula (AEF) that was temporized using an endovascular stent prior to staged open reconstruction.

METHODS

Verbal informed consent was given by the patient's family for publication of this case report. The patient presented with pulseless electrical activity secondary to hemorrhagic shock due to a massive gastrointestinal bleed. His past surgical history included an aortobifemoral bypass (ABFB) that subsequently underwent extra-anatomic reconstruction with right axillofemoral artery bypass for right femoral infected pseudoaneurysm. Two months prior to presentation, he underwent a second revision with in-situ reconstruction for left limb graft infection. CTA now demonstrated actively bleeding AEF. He was emergently treated with endovascular stenting. Once stabilized, a two-stage revision with extra-anatomic bypass and aortic stump closure for management of his AEF was performed.

RESULT

The patient was adequately stabilized using endovascular techniques followed by two-stage revision but unfortunately expired secondary to septic shock 20 days postoperatively.

CONCLUSION

This case highlights the utility of endovascular stent graft to successfully obtain hemodynamic stability and optimization prior to open repair of AEFs.

Importance of sac regression after EVAR and the role of EndoAnchors

The initial success and widespread adoption of endovascular aneurysm repair (EVAR) for the treatment of abdominal aortic aneurysms have been tempered by numerous reports of secondary interventions and increased long-term mortality compared with open repair. Over the past decade, several studies on postoperative sac dynamics after EVAR have suggested that the presence of sac regression is a benign feature with a favorable prognosis. Conversely, increasing sacs and even stable sacs can be indicators of more unstable sac behavior with worse outcomes in the long-term. Endoleaks were initially perceived as the main drivers of sac behavior. However, the observation that sac regression can occur in the presence of endoleaks, and vice versa - increasing sacs without evidence of endoleak - on imaging studies, suggests the involvement of other contributing factors. These factors can be divided into anatomical factors, patient characteristics, sac thrombus composition, and device-related factors. The shift of interest away from especially type 2 endoleaks is further supported by promising results with the use of EndoAnchors regarding postoperative sac behavior. This review provides an overview of the existing literature on the implications and known risk factors of post-EVAR sac behavior, describes the accurate measurement of sac behavior, and discusses the use of EndoAnchors to promote sac regression.

Physician-modified versus chimney endografting for pararenal aortic aneurysms: a systematic review and meta-analysis

INTRODUCTION

We performed a systematic review and meta-analysis to assess the existing published evidence regarding the safety and efficacy of the endovascular aortic repair with chimney technique (ch-EVAR) and physician-modified stent-grafts (PMSGs) for the treatment of pararenal aortic aneurysm repair.

EVIDENCE ACQUISITION

A systematic search of all relevant studies reported until October 2023 according to the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines was performed. The pooled 30-day mortality, peri- and postoperative complication rates were estimated using fixed or random effect methods.

EVIDENCE SYNTHESIS

A total of 679 study titles were identified by the initial search strategy, of which 16 were considered eligible for inclusion in the meta-analysis. A total of 1094 patients (ch-EVAR N.=861 and PMSG N.=233) (90% male) were identified. The pooled 30-day mortality rate was 3.4% for ch-EVAR and 2.6% for PMSG. The major adverse events (MAE) in the early period was 14.7% for ch-EVAR and 18.5% PMSG, respectively. Higher occlusion rate was observed of the chimney stents grafts (8.2%) than the bridging stents (1.4%) during the follow-up period.

CONCLUSIONS

Ch-EVAR and physician-modified technology are safe with low 30-day mortality in elective settings for pararenal aortic aneurysms repair. No significant differences were seen between the two surgical methods regarding the early major adverse events rate. However, higher occlusion rate for the chimneys can be expected over time.

Renal intravascular shockwave lithotripsy in complex mono Ch-EVAR

BACKGROUND

Our objective is to present the Peripheral Intravascular Lithotripsy (IVL) System in the treatment of calcific renal artery stenosis (RAS) during Chimney Endovascular Aneurysm Repair (Ch-EVAR). The Ch-EVAR technique is a bail out procedure in treating aortic aneurysms with challenging anatomy regarding the proximal sealing zone. RAS typically involves varying degrees of calcification, and final treatment can be fraught with risk of vessel's damages and suboptimal results, particularly when renal angioplasty represents the only feasible course of action in Ch-EVAR.

METHOD

We present a case of a patient with a complex juxtarenal abdominal aortic aneurysm and a pre-obstructive chalky stenosis of the right renal artery who underwent mono ChEVAR associated to visceral Intravascular Lithotripsy shockwave angioplasty.

CONCLUSION

IVL is an attractive modality for the treatment of challenging, heavily calcified renal arteries that combines the calcium-disrupting capability of lithotripsy with the familiarity of balloon catheters to facilitate proper stent deployment.

RESULT

We propose the IVL system as an additional tool in the vascular surgeon's armamentarium not only to obtain large-bore access to enable Transaortic Valve Replacement (TAVR) and EVAR but also to perform angioplasty of severely calcified visceral arteries during Ch-EVAR.

Midterm outcomes of endovascular treatment for infected aortic aneurysms: Single center experience

OBJECTIVE

The standard treatment of infected aortic aneurysms is open surgical repair but mortality rates remain high with the common cause of death being sepsis. Endovascular treatment of infected aortic aneurysms is another option and here we report the midterm outcomes of endovascular treatment for infected aortic aneurysms.

METHODS

Thirty-four patients with infected aortic aneurysms underwent endovascular and hybrid repair between December 2012 and June 2021. The patients were evaluated for early and midterm outcomes including postoperative mortality, morbidity, recurrent aortic infection, and midterm survival.

RESULTS

There were 34 patients who presented with infected aortic aneurysms with a mean age of 66.7 years (range, 26-89). Most of the patients presented with abdominal pain (94.1%) and fever (50.0%). The rate of positive blood culture for organisms was 32.4%. Salmonella was the most common organism. The procedures for treatment were endovascular repair using straight endograft, aorto-uni-iliac (AUI) endograft, bifurcated endograft, and thoracic endograft. Other procedures were endovascular repair with sandwich technique, chimney or periscope technique, and hybrid operation. The rate of in-hospital mortality and morbidity were 11.8% and 17.6%, respectively. Mean follow-up time was 21 months (range, 1-70). During the follow-up period, 7 (23.3%) patients had recurrent infection of aortic aneurysms and 5 patients required reoperation. Four patients died from septicemia and one patient died from cardiac disease. Male patients were more likely to have recurrent infection compared to females. The cumulative survival at 1 year and 2 years were 86.3% and 80.5%, respectively.

CONCLUSION

In this retrospective review of the endovascular treatment in the patients who presented with infected aortic aneurysms showed acceptable early and midterm outcomes.

First case of relining an aortic bifurcated bypass graft with the Altura endograft to treat anastomotic aneurysms

OBJECTIVE

Use of classic bifurcated endografts for relining of bifurcated aortic bypass grafts with aneurysms is usually precluded by the short distance between the lowermost renal artery and the aneurysmatic bifurcation, rendering their management challenging.

METHODS

We present the use of the Altura endograft in a case of a 75-year old male with large anastomotic aneurysms in the proximal and the left iliac amastomosis of a bifurcated aortic bypass graft. The Altura endograft consists of two separate components with a proximal D-shaped design. Its braided nitinol endoskeleton is attached only at the proximal and distal ends of the inner surface of the polyester fabric and results in adjustable lengths of the components according to the vessel diameters where they are deployed.

RESULTS

A 24 mm Altura sealed successfully at the native infarenal aortic segment covering the entire distance between the lowermost renal artery and the upper end of external iliac artery, providing successful exclusion of the aneurysms. No iliac extensions were used. The completion angiography showed no endoleaks.

CONCLUSIONS

The unique design of Altura makes it ideal for treatment of anastomotic aneurysms of bifurcated bypass grafts, overcoming anatomic limitations. To the best of our knowledge, this is the first report addressing this crucial issue.

Omniflow® II biosynthetic graft offers acceptable early and mid-term outcomes in redo surgery in patients with critical limb-threatening ischemia with no available autologous vein material

BACKGROUND

In this study, the early and mid-term outcomes of Omniflow® II (LeMaitre Vascular, Inc., Burlington, MA, USA) biosynthetic graft in redo surgery in patients with critical limb-threatening ischemia (CLTI) with no available autologous vein material were investigated with the aim to compare the outcomes obtained in "de novo" surgery versus redo surgery.

METHODS

From January 2018 until December 2022, data of CLTI patients from 18 centers in Italy with no autologous vein material underwent infrainguinal bypass with Omniflow® II biosynthetic graft were collected. Thirty-day outcome measures including intraoperative technical success, major morbidity, mortality, and graft patency were assessed and compared. At two-year follow-up, estimated outcomes of survival, primary patency, primary assisted patency, secondary patency, freedom from reintervention, and amputation-free survival were analyzed using Kaplan-Meier curves and compared between groups using the log-rank test.

RESULTS

In the study period 119 CLTI patients had an infrainguinal bypass with Omniflow® II biosynthetic graft. Seventy-seven patients (64.7%) underwent bypass as "de novo" treatment (group de novo), whilst in the remaining 42 patients (35.3%) the procedure was performed as redo surgery due to occlusion and/or infection of a previous bypass graft (group redo). Two groups were homogeneous in terms of demographic, clinical, and morphological data. In group redo explantation of an infected prosthetic graft was needed in 4 cases (9.5%). Intraoperative technical success was achieved in all cases in both groups. At 30 days, the overall patency rate did not differ between the two groups (69/77, 89.6%, group de novo vs. 35/42, 83.3%, group redo; P=0.24), whilst in group redo limb loss was higher with a statistically significant different 30-day major amputation rate between the two groups (11.9% group redo vs. 1.3% group de novo; P<0.001). Overall median duration of follow-up was eight months (IQR 6-13). At two-year follow-up there were no differences between the two groups in terms of survival (67.7% group de novo vs. 55.8% group redo, P=0.53), primary patency (34.4% group de novo vs. 26.8% group redo, P=0.25), primary assisted patency (43.6% group de novo vs. 28.8% group redo, P=0.12), freedom from reintervention (64.1% group de novo vs. 68.8% group redo, P=0.98), and amputation-free survival (67.8% group de novo vs. 60% group redo, P=0.12). Secondary patency was significantly higher in group de novo (53.7% vs. 32.3%, P=0.05). During the follow-up, the overall rates of graft infection and aneurysmal degeneration were 3.4%, and 0.8%, respectively.

CONCLUSIONS

Nevertheless, poorer early outcomes in terms of limb salvage, Omniflow® II biosynthetic graft offers acceptable ywo-year outcomes in redo surgery in CLTI patients with no available autologous vein material. Further studies with larger population sizes are needed to validate these outcomes.