First-in-Human Clinical Trial of the WeFlow-JAAA Endograft System in Patients With Juxtarenal Abdominal Aortic Aneurysms.

OBJECTIVE: To preliminarily evaluate the safety and efficacy of the WeFlow-JAAA endograft, a novel off-the-shelf device designed for the repair of juxtarenal abdominal aortic aneurysms (JRAAAs) and pararenal abdominal aortic aneurysms (PRAAAs). METHODS: This prospective single-arm first-in-human clinical trial included patients with JRAAAs (infrarenal necks ≤10 mm) or PRAAAs with at least a 5 mm sealing zone below the superior mesenteric artery (SMA) who underwent endovascular repair using the WeFlow-JAAA endograft system. With this system, the celiac artery was addressed with a wide scallop, the renal arteries (RAs) were addressed with 2 standard inner branches, and the SMA was addressed with a "mini-inner-cuff" reinforced fenestration. The primary efficacy endpoint was the clinical success at 12 months. The primary safety endpoint was the freedom from major adverse events (MAEs) in the first 30 days after surgery. RESULTS: Fifteen patients (all men; mean age 68.5±6.0 years) were enrolled between October 2019 and August 2021. The median infrarenal neck length was 0 mm (IQR, 0-4 mm). Technical success was achieved in all patients. No MAEs occurred in the first 30 days. The mean fluoroscopy time was 73.1±27.8 minutes, and the mean volume of contrast media was 130.7±29.4 mL. Clinical success was maintained in all patients at 12 months. No aortic-related deaths, aneurysm rupture, type I or type III endoleak, or open surgery conversion occurred during the follow-up period. The secondary intervention was required only in 1 patient who developed an occluded right RA stent 14 months after the procedure. CONCLUSION: The WeFlow-JAAA endograft device appears to be safe and efficacious in selected patients with JRAAAs or PRAAAs with more than 5 mm sealing zone below SMA. Large-scale, multicenter, and prospective studies with long-term follow-ups are ongoing to validate our findings in China. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT04745546 (URL: Guo's Visceral Arteries Reconstruction: The First in Man Study of WeFlow-JAAA Stent Graft System-Full-Text View-ClinicalTrials.gov). CLINICAL IMPACT: The first-in-human clinical trial of the WeFlow-JAAA endograft system demonstrates promising safety and efficacy in treating juxtarenal abdominal aortic aneurysms (JRAAAs) and partial pararenal abdominal aortic aneurysms (PRAAAs). This innovative off-the-shelf device offers a potential alternative to traditional endovascular aortic repair. The successful outcomes, including technical success in all patients, freedom from major adverse events, and maintenance of clinical success at 12 months, suggest a potential shift in clinical practice towards using the WeFlow-JAAA endograft system for selected patients. This study paves the way for larger-scale, multicenter, prospective studies to further validate its long-term safety and efficacy, offering clinicians a new option for managing complex abdominal aortic aneurysms.

Additional Aortic Coverage With an Off The Shelf, Multibranched Endograft Compared With Custom Made Devices For Endovascular Repair of Pararenal Abdominal Aortic Aneurysms.

OBJECTIVE: Pararenal abdominal aortic aneurysms (p-AAA) require complex endovascular aortic repair or open surgical repair with suprarenal clamping. Custom made devices (CMD), including fenestrated and branched endovascular aortic repair (F/B-EVAR) or off the shelf (OTS) multibranched devices, are available treatment options. The aim of this study was to determine the additional healthy aortic coverage using an OTS multibranched endograft vs. a CMD for the treatment of p-AAAs. METHODS: This was a retrospective single centre analysis of prospectively collected data. Consecutive patients with p-AAAs requiring a proximal landing zone above the coeliac artery (CA), planned and treated with CMDs (Zenith Fenestrated) between January 2017 and December 2021 were included in this study. Treatment with supracoeliac coverage using available OTS multibranched devices was simulated using available pre-operative images: T-Branch; E-nside; and TAMBE. Study endpoints included the need for additional proximal aortic coverage, and the number of the segmental arteries additionally covered proximally from the CA for OTS devices compared with CMDs. RESULTS: Eighty three patients with p-AAAs were treated with CMDs (all FEVAR), including juxtarenal AAAs (n = 46; 56%), suprarenal AAAs (n = 20; 24%), and short neck AAAs (n = 17; 20%). In this study, treatment with 249 (3 × 83) OTS endografts was simulated. When compared with CMDs, OTS devices required a mean of 74 ± 19 mm of additional proximal healthy aortic coverage from the CA (CMD: 33 ± 19 mm vs. OTS: 108 ± 6 mm; p ≤ .001), as well as an average sacrifice of 2.5 additional segmental arteries (CMD: 1.3 ± 0.8 vs. OTS: 3.8 ± 0.9; p ≤ .001). In 94% of patients, at least one of the available multibranched endografts could have been implanted in accordance with instructions for use. CONCLUSION: Despite not requiring customisation time, OTS endografts for the treatment of p-AAA lead to more extensive healthy aortic coverage, as well as an average sacrifice of 2.5 additional segmental arteries, compared with CMDs. When compared with OTS devices, CMDs appear to limit the extent of unnecessary aortic coverage and the theoretical subsequent risk of spinal cord ischaemia.

Endovascular Treatment of Ruptured or Symptomatic Thoracoabdominal and Pararenal Aortic Aneurysms Using Octopus Endograft Technique: Mid-Term Clinical Outcomes.

OBJECTIVE: To evaluate the effectiveness and safety of using off-the-shelf "Octopus" technique to treat ruptured or symptomatic thoracoabdominal aortic aneurysm (TAAA) and pararenal abdominal aortic aneurysm (PRAAA). METHODS AND RESULTS: All cases who underwent "Octopus" technique from May 2016 to May 2019 at our center were retrospectively analyzed. A total of 10 cases (8 males) were included. The mean age was 54.5±14.2 years (range: 31-80 years). Eight cases presented as aneurysm rupture or impending rupture accepted emergency repair. Technical success, defined by placement of all endografts as planned, was achieved in all cases. A total of 30 target visceral branches were successfully cannulated, 9 celiac arteries were covered intentionally. Intraoperative endoleak was observed in 6 patients, all of them were gutter leak. During hospital stay, there was no death, no side branch occlusion or spinal cord ischemia. Median follow-up was 30 months (range: 12-50 months). One patient died of lung cancer at 14-month follow-up. There was no secondary endoleak. The primary endoleak were found spontaneously resolved in 3 cases at 7 days, 3-month, and 1-year imaging. One persistent endoleak totally resolved after sealing of gutter spaces at 4-month follow-up. The other 2 persistent endoleak decreased during follow-up, which are still under observation. The branch patency rate was 90.3% (28/31). All the 3 occluded branches were renal arteries. Branch occlusion occurred in 2 cases at 1-month follow-up and 1 case at 2-year follow-up, but renal insufficiency was not observed in these cases. Obvious aneurysm sac shrinkage (≥5 mm) was observed in all cases. The aneurysm size shrunk from 7.6±1.9 to 5.5±1.4 cm. No spinal cord ischemia occurred during follow-up. CONCLUSION: Treatment of ruptured TAAA and PRAAA with "Octopus" technique is feasible and safe for high surgical risk patients in the absence of fenestrated and branched devices. The long-term clinical outcomes needed to be investigated.

Systematic Review and Meta-Analysis of Published Studies on Endovascular Repair of Abdominal Aortic Aneurysm With the p-Branch.

Background: Endovascular treatment of juxtarenal or pararenal abdominal aortic aneurysms is more popular than open surgery, mainly because it reduces perioperative mortality and morbidity. The custom-made fenestrated devices need to be tailored to each patient, so these devices require extra manufacturing and shipping time. The increased wait time may increase the risk of aneurysm rupture in some patients. In some situations, "Off-the-shelf" (OTS) fenestrated grafts can be used. The Cook Zenith p-Branch device (William Cook Australia, Brisbane, Australia) is a relatively common OTS. This study aimed to systematically evaluate all published experiences with p-Branch. Methods: We searched PubMed, Embase, and Cochrane to find works of literature that reported on the outcomes of patients treated with the p-Branch stent-grafts. Then we conducted an assessment of quality and meta-analysis of the results. The primary endpoints were the application rate of p-Branch stent-graft (type A, B), technical success rate, and early re-intervention rate. We estimated pooled proportions and 95% CIs. Results: Initial search of the literature included 111 articles, of which 7 studies were included in the end. A total of 260 patients were enrolled in these studies, and 218 patients were eventually treated with p-Branch. The pooled application rate of type A devices was 48% (95% CI, 29-67%), and pooled application rate of type B devices was 30% (95% CI, 16-44%). The pooled technical success rate was 87% (95% CI, 75-98%). The early re-intervention rate was 10% (95% CI, 3-17%). Midterm renal infarct rate (after 30 days) was 3% (95% CI, 0-6%). Midterm re-intervention rate (after 30 days) was 30% (95% CI, 3-57%). Midterm renal failure rate (after 30 days) was 6% (95% CI, 2-10%). Conclusions: This pooled analysis indicated an acceptable technical success rate after p-Branch stent-graft implantation, with early and midterm re-intervention rate and renal failure rate that cannot be ignored. The p-Branch repair of juxtarenal abdominal aortic aneurysms may be an appropriate and safe option, especially in emergency situations.

Retrograde branched extension limb assembling stent of pararenal abdominal aortic aneurysm: A longitudinal hemodynamic analysis for stent graft migration.

PURPOSE: Pararenal abdominal aortic aneurysms (PRAAAs) are a life-threatening disease, and hemodynamic analysis may provide greater insight into the effectiveness and long-term outcomes of endovascular aneurysm repair (EVAR). However, the lack of patient-specific boundary conditions on the periphery compromises the accuracy. Windkessel (WK) boundary conditions coupled to hemodynamic follow-up models of a PRAAA patient, aims to provide insights into the link between hemodynamics and poor prognosis. METHOD: One PRAAA patient underwent EVAR and reintervention after one branch of stent-graft (SG) had migrated. Totally five computational follow-up models were studied. Patient-specific flow data acquired via ultrasound were used to define the boundary conditions in the ascending aorta and the following three branches. Coupled zero-dimensional WK models representing the distal vasculature were used to define the outlet boundary conditions under the abdomen. RESULTS: Flow divisions of the main SG branches were 40.7% and 24.7%, respectively. Time-averaged wall shear stress and oscillatory shear index (OSI) increased at the junction connected the SG branch and the stent leading to the right common iliac artery (RCIA) where the stent migrated. The OSI and relative residence time (RRT) value in superior mesenteric artery increased notably after the migration, the RRT continuously increased following the reintervention. CONCLUSION: Unbalanced flow, resulting in locally high-speed flow, high WSS and OSI might significantly affect stent stability. Results suggest that diameters and interconnection design of stents in complex cases should take the flow division into consideration and computational simulations might be considered as a tool for intervention protocol design.

Recent Development and Long-Term Results of Open vs EVAR for Pararenal Abdominal Aortic Aneurysms.

In this article, I would like to discuss on the two different treatment options (Open vs EVAR) for pararenal abdominal aortic aneurysm (the term "PRAAA" is not clearly defined and classified). Recently, complex endovascular treatment [Fenestrated EVAR (F-EVAR), Chimney (Snorkel) EVAR (C-EVAR, S-EVAR), Branched EVAR (B-EVAR)] have been developed and applied in selected patients, with encouraging early results; however, the high rate for secondary reinterventions and long-term results remain uncertain. This article introduce new devices and a new concept with endovascular aneurysm sealing (EVAS) are currently available on the market for the treatment of PRAAA. Open repair of PRAAA can be performed with low mortality and long-term survival is favorable from single-center experience in the real world and others. We conclude that open repair remains the golden standard treatment in most centers for PRAAA. However, EVAR of PRAAA may represent an alternative option in high-risk patients. Because the indications and circumstances for PRAAA vary based on patient-specific comorbidities and anatomy, it is recommended that vascular surgeons should be familiar with both treatment strategies and tailor-made strategy for improved long-term results for PRAAA. (This is a translation of Jpn J Vasc Surg 2018; 27: 303-308.).

Results of open pararenal abdominal aortic aneurysm repair: single centre series and pooled analysis of literature.

Objectives Endovascular treatment of pararenal abdominal aortic aneurysm has gained terrain over the past decade, despite the substantial need for reinterventions during follow-up. However, open repair is still a well-established treatment option. With the current study we report the results of a consecutive series of elective primary open pararenal abdominal aortic aneurysm repair in a tertiary vascular referral centre, combined with an overview of current literature and pooled data analysis of perioperative mortality of open and endovascular pararenal abdominal aortic aneurysm repair. Methods A retrospective analysis of a prospective database of all elective open pararenal abdominal aortic aneurysm repairs in the St. Antonius Hospital between 2005 and 2014 was performed. Primary endpoint was 30-day mortality. Secondary endpoints were 30-day morbidity, new onset dialysis, reintervention free survival, and overall survival during follow-up. Results Between 2005 and 2014, 214 consecutive patients underwent elective open pararenal abdominal aortic aneurysm repair. Mean age was 69.8 (±7.1) years, 82.7% (177/214) were men, and mean abdominal aortic aneurysm diameter was 62 (±11) mm. Thirty-day mortality was 3.4%. Thirty-day morbidity was 27.1%, which predominantly consisted of pneumonia (18.7% (40/214)), cardiac events (3.3% (7/214)), and new onset dialysis (2.8% (6/214)). Estimated five-year overall survival rate was 74.2%. 0.9% (2/214) of patients required abdominal aortic aneurysm-related reintervention, and an additional 2.3% (5/214) required surgical repair of an incisional hernia. Pooled analysis of literature revealed a 30-day mortality of 3.0% for open pararenal repair and 1.9% for fenestrated endovascular repair. Conclusion Open pararenal abdominal aortic aneurysm repair in the era of increasing endovascular options results in acceptable perioperative morbidity and mortality rates. Mid-term reintervention rate is low compared to fenestrated endovascular aneurysm repair. Expertise with open repair still remains essential for treatment of pararenal abdominal aortic aneurysms in the near future, especially for those patients that are declined for endovascular treatment.

Endovascular Treatment for Pararenal Abdominal Aortic Aneurysm Using the Chimney Technique for Bilateral Renal Arteries / 日本心臓血管外科学会雑誌

Endovascular aneurysm repair (EVAR) of pararenal abdominal aortic aneurysm (pararenal AAA) includes fenestrated or branched endografts, and the chimney technique. However, fenestrated and branched endografts are not currently available. An 82-year-old man, who underwent EVAR two years previously, was admitted to our hospital because of pararenal AAA measuring 56 mm. He underwent endovascular treatment with the chimney technique for bilateral renal arteries. We used a self-expanding and balloon-expandable uncovered-stent in renal arteries. Postoperatively he had slight renal dysfunction and acute pancreatitis, but was discharged 14 days after surgery. EVAR with the chimney technique for bilateral renal arteries was thought to be useful in high risk patients with pararenal AAA.

Surgeon-Modified Zenith Stent Graft System for Endovascular Repair of Abdominal Aortic Aneurysm with Short Proximal Neck / 日本心臓血管外科学会雑誌

Endovascular repair for abdominal aortic aneurysm (EVAR) has become widespread in Japan because of its low invasiveness. However adequate proximal neck length is required for EVAR. Unfortunately the surgical mortality of para-renal aortic aneurysm cases has been higher than that of infrarenal aortic aneurysm cases, especially in high-risk patients. A manufacture-modified fenestrated Zenith stent graft system has already been developed, however this new device is not yet available in Japan. Furthermore this device could not be used in an emergency situation because it takes 2-3 weeks for preparation. Therefore we introduced a surgeon-modified fenestrated Zenith stent graft (fenestrated Zenith) system in December 2010 for patients with a proximal neck length of 5-10 mm. The fenestrated Zenith was not indicated if the supra-renal angle and proximal neck angle exceeded 35°. From May 2007 to February 2012, abdominal aortic aneurysms (AAA) with a short neck were repaired with fenestrated Zenith in 11 high-risk patients (group Fene), and AAAs with a proximal neck length of more than 15 mm were repaired with a standard Zenith in 43 patients (group IFU). There were two ruptured AAA in the Fene group. Proximal neck length was significantly shorter in the Fene group (5.5±1.4 mm in the Fene group, 26.4±9.5 mm in the IFU group, <i>p</i><0.0001) and proximal neck angle was significantly less in the Fene group (20±13° in the Fene group, 36±18° in the IFU group, <i>p</i>=0.008). The Zenith stentgraft system was deployed successfully in all patients. The frequency of type Ia endoleak detected by angiography after stent graft deployment and balloon attachment did not differ significantly (36% in the Fene group 26% in the IFU group, <i>p</i>=0.475) and the frequency of Palmaz stent requirement for type Ia endoleak which persisted after 10 min of additional balloon attachment also did not differ significantly (27% in Fene group, 9% in IFU group). All fenestrated renal arteries were shown to be patent by angiography. There was no hospital death despite 2 cases of ruptured AAA, nor were these major complications in either group. Serum creatinine levels at 1, 3, 6 and 30 days after EVAR did not differ significantly between the 2 groups. In 9 out of 11 patients, only type II endoleaks were detected and aneurysm shrinkage tended to be more in Fene group (9.9±5.7 mm in Fene group, 5.4±6.1 mm in IFU group, <i>p</i>=0.062) on enhanced CT 6 months after EVAR. Also all fenestrated renal arteries were patent in these 9 patients. The surgeon-modified fenestrated Zenith system seemed to be effective for AAA patients with short proximal necks, but long term follow up is mandatory.