Background/Objectives: Carbon dioxide digital-subtraction angiography (CO₂-DSA) is an increasingly adopted technique in endovascular aortic repair (EVAR) and fenestrated/branched EVAR (F/B-EVAR); it is used to reduce the amount of iodinate contrast medium (ICM) and prevent postoperative renal function worsening (PO-RFW). Our aim is to report results from the literature on EVAR and F/B-EVAR procedures using CO₂-DSA, together with wider applications in aortic endovascular treatment. Methods: We performed a literature review by searching electronic databases for published data on CO₂-DSA during EVAR and F/B-EVAR procedures. The endpoints were postoperative renal function worsening (PO-RFW) and efficacy of intraoperative arterial visualization. Further, applications of CO₂ for thoracic endovascular aortic repair (TEVAR) were described. Results: Seventeen studies reporting results on CO₂-DSA in EVAR (644 patients) were retrieved. Overall, 372 (58%) procedures were performed with CO₂ alone, and 272 (42%) were performed with CO₂+ICM. Eight studies analyzed the effect of CO₂-DSA angiography on PO-RFW; four studies showed a significantly lower rate of PO-RFW compared to ICM. Five studies (153 patients) analyzed intraoperative arterial visualization with CO₂-DSA; renal and hypogastric arteries were effectively visualized in 69% and 99% of cases, respectively. The use of CO₂-DSA in F/B-EVAR has not been widely investigated. The largest series reported that PO-RFW was lower in the CO₂ vs. ICM group. Conclusions: Carbon dioxide is widely applied in modern aortic endovascular treatment. CO₂-DSA for EVAR and F/B-EVAR is an efficient technique for reducing PO-RFW while allowing acceptable arterial intraoperative visualization.

Objective: Numerous articles have reported an increased incidence of limb graft occlusion (LGO) with the Cook Zenith Alpha endograft compared with other endografts in endovascular aortic aneurysm repair (EVAR). The present study aimed to assess the rate of LGO after EVAR in particular with the Cook Zenith Alpha device when adhering to a standardised protocol designed to prevent limb related complications. Methods: This was a non-sponsored retrospective study performed in two university vascular surgery centres employing the same protocol for limb complication prevention during EVAR from 2016 to 2019. The protocol encompassed: (1) angioplasty of any common or external iliac artery with > 50% stenosis before endograft navigation; (2) proximal sealing zone of limbs at the same level of the fl ow divider with minimum overlap, which is more restrictive than the Cook Zenith Alpha instructions for use; (3) semi-compliant kissing ballooning of limbs; (4) limb stenting for any residual tortuosity, kinking, or stenosis; and (5) adjunctive common and external iliac stenting for residual stenosis or dissection after EVAR. Patients enrolled in this study were treated with standard aortobi-iliac EVAR. Follow up was performed by clinical visit and duplex ultrasonography at discharge, six months, and yearly thereafter. The primary endpoint was to evaluate the LGO rate with different EVAR devices (Cook Zenith Alpha, Gore C3, and Medtronic Endurant) and to determine potential risk factors for LGO associated with the Zenith Alpha. Results: In the study period, 547 EVARs were considered: 233 (42.6%) Cook Zenith Alpha, 196 (35.8%) Gore Excluder, and 118 (21.6%) Medtronic Endurant. The mean follow up was 44 +/- 23 months, and the fi ve year freedom from LGO was 97 +/- 3%, without differences between groups (97 +/- 2%, 95 +/- 3%, and 100% with Cook Zenith Alpha, Medtronic Endurant, and Gore Excluder, respectively; p = .080). In the Zenith Alpha group, intraoperative adjunctive iliac artery angioplasty, iliac artery stenting, or iliac limb stenting was performed in 8%, 3.4%, and 9.7% of cases, respectively. Analysis of potential risk factors for LGO identified external iliac artery distal landing and large main bodies (ZIMB 32- 36) to be independently associated with LGO during follow up (hazard ratio [HR] 18, 95% confidence interval [CI] 3- 130, p = .004; and HR 12, 95% CI 1.2- 130, p = .030, respectively). Conclusion: The present experience with a protocol for limb complication prevention allows achievement of a low rate of LGO at fi ve years with Zenith Alpha endografts similar to other endografts. Specific risk factors for the Cook Zenith Alpha endograft are external iliac artery distal landing and the use of a large main body (ZIMB 32- 36).

Paravisceral aortic lesions present significant challenges for endovascular treatment. This retrospective analysis of consecutively treated patients from April 2017 to June 2021 aimed to analyse the outcome of primary intra-operative embolisation of aortic complicated pseudoaneurysms and gutter channels during parallel graft (PG) repair of paravisceral symptomatic aortic pseudoaneurysms. Patients with symptomatic pseudoaneurysms of the paravisceral aorta treated with PGs using chimney or periscope configurations were included. Thoracic endografts were positioned to exclude the aortic lesions. Coil embolisation of both the lesions and gutter channels was performed after graft deployment and prior to ballooning of the stent grafts. The primary endpoints were technical success (defined as exclusion of the pseudoaneurysm, target visceral vessel [TVV] patency, absence of gutter endoleaks) and clinical success (technical success + resolution of symptoms + absence of major adverse events) at 30 days. Secondary endpoints included overall survival, TVV patency, gutter endoleaks, and freedom from re-interventions during follow up. Six patients (four women) were treated for pseudoaneurysm rupture (three cases) and symptomatic aortic pseudoaneurysm (three cases) of the paravisceral aorta. The patients' anatomies were unsuitable for off the shelf devices and patients were all deemed to be at prohibitive surgical risk. A total of 15 TVVs were revascularised (comprising three coeliac arteries, five superior mesenteric arteries, and seven renal arteries) using 10 chimney and five periscope PGs. One coeliac artery was occluded. Seventy coils were deployed to embolise both the aortic ruptures and gutter channels. Both technical and clinical success rates were 100%. The median follow up was 17 months (IQR 5, 35), during which time three patients died due to non-aortic related causes. One coeliac artery (6%) was occluded, and no endoleak evidence was found. Primary intra-operative embolisation during parallel graft endovascular repair of paravisceral symptomatic aortic pseudoaneurysms may be both safe and effective in excluding the pseudoaneurysm when other options are unavailable.

Objectives: The study objectives are to evaluate the impact of the operator’s learning curve on the outcomes of off-the-shelf branched endovascular aortic repair (OTS-BEVAR) in complex and thoracoabdominal (C/TAAAs) aneurysms. Methods: Patients who underwent OTS-BEVAR (T-Branch, Cook-Medical) between 2013 and 2023 were considered. The first and last 25 cases with at least 1 year of follow-up were clustered in two groups (early experience: E.Exp.; late experience: L.Exp.) and compared. Technical success (TS), intraoperative target visceral vessel (TVV) loss, spinal cord ischemia (SCI), 30-day mortality, and TVV instability at 1 year were assessed as primary outcomes. Procedure/fluoroscopy time, iodinated contrast media (ICM) amount and length of hospitalization were assessed as secondary outcomes. A p value < 0.05 was considered statistically significant. Results: Overall, 106 cases were analyzed. Technical success was higher in L.Exp. than E.Exp. (L.Exp.: 25/25 vs. E.Exp.: 17/25; p: 0.004). Moreover, intraoperative TVVs loss was higher in E.Exp. than L.Exp. (E.Exp.: 12/25 vs. L.Exp.: 0/25; p: 0.0001). There were no differences in terms of 30-day/in-hospital mortality (E.Exp.:4/25 vs. L.Exp.:4/25; p: 1), SCI (E.Exp.:2/25 vs. L.Exp.:1/25; p: 1), and paraplegia (E.Exp.: 2/25 vs. L.Exp.: 0/25; p: 0.48) between E.Exp. and L.Exp. Cases of L.Exp. had lower fluoroscopy [E.Exp.: 160(21) vs. L.Exp.:72(18) min; p: 0.003] and overall procedure time [E.Exp.: 518(156) vs. L.Exp.:400(130) min; p: 0.04], ICM [EE: 220(45) vs. L.Exp.: 138(61) mL; p: 0.005] and hospitalization [E.Exp.: 17(9) vs. L.Exp.: 12(4) days; p: 0.03] than cases of E.Exp. Finally, patients managed in L.Exp. had lower TVVs instability at 12 months than patients managed in the E.Exp. (E.Exp.: 8/25 vs. L.Exp.: 1/25; p: 0.04). Conclusions: Cases managed in L.Exp. have higher TS, lower intraoperative TVVs loss and instability at 1-year than cases of E.Exp. Moreover, procedural/fluoroscopy time, ICM, radiation exposure and hospitalization are lower in L.Exp. than E.Exp.