Endovascular Repair of One-hundred Urgent and Emergent free or Contained Thoraco-abdominal Aortic Aneurysms Ruptures. An International Multi-Center Trans-Atlantic experience.

OBJECTIVE: To analyze the outcomes of urgent/emergent endovascular aortic repair of patients with free/contained ruptured thoracoabdominal aortic aneurysms (rTAAA). BACKGROUND: Endovascular repair of rTAAA has been scarcely described in emergent setting. METHODS: An international multicenter retrospective observational study (ClinicalTrials.govID:NCT05956873) from January-2015 to January-2023 in 6 European and 1 United States Vascular Surgery Centers. Primary end-points were technical success, 30-day and/or in-hospital mortality and follow-up survival. RESULTS: A total of 100 rTAAA patients were included (75 male; mean age 73 y). All patients (86 contained and 14 free ruptures) were symptomatic and treated within 24-hours from diagnosis: multi-branched off-the-shelf devices (Zenith t-branch,Cook Medical Inc.Bjaeverskov,Denmark) in 88 patients, physician-modified endografts in 8, patient-specific device or parallel grafts in two patients each. Primary technical success was achieved in 89 patients and 30-day and/or in-hospital mortality was 24%. Major adverse events (MAEs) occurred in 34% of patients (permanent dialysis and paraplegia in 4 and 8 patients, respectively). No statistical differences were detected in mortality rates between free and contained ruptured patients (43%vs.21%; P =0.075). Multivariate analysis revealed contained rupture favoring technical success (Odd-Ratio10.1;95%Confidence-Interval:3.0-33.6; P =<0.001). MAEs (OR9.4;95%C-I:2.8-30.5; P =<0.001) and pulmonary complications (OR11.3;95%CI:3.0-41.5; P =<0.001) were independent risk factors for 30-day and/or in-hospital mortality. Median follow-up time was 13 months (interquartile range 5-24); 1-year survival rate was 65%. Aneurysm diameter>80 mm (Hazard-Ratio:2.0;95%CI:1.0-30.5; P =0.037), technical failure (HR:2.6;95%CI:1.1-6.5; P =0.045) and pulmonary complications (HR:3.0;95%CI:1.2-7.9; P =0.021) were independent risk factors for follow-up mortality. CONCLUSION: Endovascular repair of rTAAA shows high technical success; the presence of free rupture alone appear not to correlate with early mortality. Effective prevention/management of post-operative complications is crucial for survival.

Multicenter Study to Evaluate Endovascular Repair of Extent I-III Thoracoabdominal Aneurysms Without Prophylactic Cerebrospinal Fluid Drainage.

OBJECTIVE: To assess outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) of Extent I-III thoracoabdominal aortic aneurysms (TAAAs) without prophylactic cerebrospinal fluid drainage (CSFD). BACKGROUND: Prophylactic CSFD has been routinely used during endovascular TAAA repair, but concerns about major drain-related complications have led to revising this paradigm. METHODS: We reviewed a multicenter cohort of 541 patients treated for Extent I-III TAAAs by FB-EVAR without prophylactic CSFD. Spinal cord injury (SCI) was graded as ambulatory (paraparesis) or nonambulatory (paraplegia). Endpoints were any SCI, permanent paraplegia, response to rescue treatment, major drain-related complications, mortality, and patient survival. RESULTS: There were 22 Extent I, 240 Extent II and 279 Extent III TAAAs. Thirty-day mortality was 3%. SCI occurred in 45 patients (8%), paraparesis occurring in 23 (4%) and paraplegia in 22 patients (4%). SCI was more common in patients with Extent I-II compared with Extent III TAAAs (12% vs. 5%, P =0.01). Rescue treatment included permissive hypertension in all patients, with CSFD in 22 (4%). Symptom improvement was noted in 73%. Twelve patients (2%) had permanent paraplegia. Two patients (0.4%) had major drain-related complications. Independent predictors for SCI by multivariate logistic regression were sustained perioperative hypotension [odds ratio (OR): 4.4, 95% confidence interval (95% CI): 1.7-11.1], patent collateral network (OR: 0.3, 95% CI: 0.1-0.6), and total length of aortic coverage (OR: 1.05, 95% CI: 1.01-1.10). Patient survival at 3 years was 72%±3%. CONCLUSION: FB-EVAR of Extent I-III TAAAs without CSFD has low mortality and low rates of permanent paraplegia (2%). SCI occurred in 8% of patients, and rescue treatment improved symptoms in 73% of them.

Performance of the Gore VBX Balloon Expandable Endoprosthesis as Bridging Stent-Graft in Branched Endovascular Aortic Repair for Thoracoabdominal Aneurysms.

PURPOSE: Bridging stent stability is crucial for efficacy and safety of branched aortic endovascular repair (bEVAR) of thoracoabdominal aortic aneurysms (TAAAs). In this study, we assess the performance of the new Viabahn Balloon-Expandable endoprosthesis (VBX) in bEVAR. Based on our learning curve we give recommendations for a safe and effective use of the device. MATERIALS AND METHODS: We prospectively collected the data of patients with TAAAs undergoing bEVAR between December 2017 and December 2019. All patients with implantation of at least 1 VBX stent-graft as bridging stent were included in our single-center analysis. Demographic, comorbidity, and computed tomography angiography (CTA) data of 112 patients were retrospectively evaluated. Primary endpoint was a composite of branch-related technical success and freedom from target vessel instability. Secondary endpoints were clinical and ongoing clinical success. RESULTS: Primary endpoint: technical success was achieved in all patients (100%) with a freedom from target vessel instability of 96.3% after a median follow-up of 18 months. Overall mortality was 13.4% (n=15) and 13 patients underwent secondary interventions, 12 of them are still alive and 1 suffered from aneurysm sac expansion, consequently an ongoing clinical success of 75.9% was reached. After modification of the implantation technique during the course of the study by selecting longer stent lengths after accurate estimation of vessel curvature and expected adaptation of the flexible endoskeleton to the specific anatomical conditions, no type Ic endoleaks were observed in the last 70 cases. CONCLUSIONS: The VBX stent-graft can be safely used as bridging stent for branched thoracoabdominal repair. However, learning curve should be considered to avoid type Ic endoleak and edge stenosis. Based on this experience longer landing zones and 2-step deployment of VBX are useful for successful bridging also of challenging target vessels.

Fatigue Resistance of the Advanta V12/iCast and Viabahn Balloon-Expandable Stent-Graft as Bridging Stents in Experimental Fenestrated Endografting.

PURPOSE: Bridging stents undergo millions of cycles during respiratory movements of the kidneys throughout the patient's life. Thus, understanding the response of fabric and endoskeleton of the stent to cyclic loading over the time is crucial. In this study, we compare the fatigue resistance of the Viabahn Balloon-Expandable stent-graft (VBX) with the widely used Advanta V12/iCast under prolonged stress induction. MATERIALS AND METHODS: A polyester test sheet with 10 fenestrations was used simulating a fenestrated endograft. Five 6×59 mm VBX stent-grafts and five 6×58 mm Advanta stent-grafts were implanted into 6×6 mm fenestrations. The stents were flared with a 10×20 mm PTA (percutaneous transluminal angioplasty) catheter and connected with a fatigue stress machine. All stent-grafts were evaluated by microscopy and radiography at baseline and after regular intervals until 50,000,000 cycles were applied, simulating a life span of approximately 75 months. Freedom from fracture (FF), freedom from initial polytertafluoroethylene (PTFE) changes (FIC), and from PTFE breakpoint (FBP, all-layer defect) were calculated. RESULTS: Digital radiographic images did not show any stent fracture in both groups after 50,000,000 cycles. The VBX stent-graft was free from any all-layer defects at the conclusion of 50,000,00 cycles resulting in a significant higher FBP compared with Advanta V12 (50,000,000 vs 33,400,000; p<0.01). All-layer defects were observed only in the Advanta group. Two of 5 Advanta stents showed early penetration of the nitinol ring causing a defect of PTFE. Regarding FIC, there was no significant difference between the stents (3,400,000 in VBX vs 3,200,000 in Advanta). CONCLUSIONS: In fatigue tests simulating respiration movements, VBX and Advanta V12 performed equally well in terms of fracture resistance and freedom from initial PTFE changes. VBX maintained freedom from PTFE breakpoint throughout the full 50,000,000 cycles. All-layers defects were detected only in Advanta and were mainly caused by penetration of the nitinol ring through the PTFE.

Treatment of iliac atherosclerotic lesions using the balloon-expandable dynamic bare metal stent: One-year outcomes of the BIODYNAMIC single-center retrospective analysis.

OBJECTIVES: Endovascular therapy using balloon expandable stents has become the treatment standard for most iliac atherosclerotic lesions. We aimed to assess the safety and performance of the Dynamic stainless-steel balloon-expanding stent system in this location. METHODS: BIODYNAMIC is a retrospective single center study including consecutive patients with iliac lesions treated with the Dynamic stent system. Not included were implantations inside an endograft. The primary endpoint was freedom from major adverse limb events (MALE) at 12 months, defined as index limb amputation or target lesion revascularization (TLR). Secondary endpoints were procedure success, ankle brachial index (ABI) and Rutherford class change, mortality and freedom from TLR after 12 months. RESULTS: Within two years, 182 patients with 234 lesions in the common iliac artery were enrolled. Rutherford class 5 and 6 were present in 11.5% of patients, average stent diameter was 8.0 ± 0.5 mm and stented length 40.0 ± 15.3 mm. The primary endpoint was reached in 96.2% (225/234) of the cases, with six TLR (2.6%) and three target limb amputations (1.3%). Procedure success was obtained in all but three patients (98.4%). In paired analysis, ABI improved by 0.25 ± 0.21 from baseline to 0.90 ± 0.16 post-procedure and Rutherford class improved by -1.75 ± 1.53. There were four non-device-related deaths (2.2%). Freedom from TLR was 97%, 95.3%, 94% and 92.7% at 24, 36, 48 and 60 months, respectively. CONCLUSION: The Dynamic balloon-expandable stent system proved to be safe and effective in a population with common iliac artery lesions.