From a bailout procedure to a standardised therapeutic option

From a bailout procedure In this context, PERICLES also demonstrated that the risk of stent instability to a standardised therapeutic rises as the number of chimney stent grafts used increases. However, recent data option: Ten-year anniversary show comparable good results in multiple chimneys when technical details are from the first publication of the observed.11 Another point of discussion is the stroke abdominal use of ChEVAR in risk after ChEVAR. This complication is related to the antegrade cannulation of the symptomatic patients renal and visceral vessels. The use of bilateral upper extremity access was found to be an independent predictor factor associated with In this article, Giovanni Torsello tracks the evolution of the chimney endovascular a 2.8-fold increased risk for postoperative aneurysm repair (ChEVAR) procedure, and how it has developed from a “mere stroke.12 Using a single-arm access point bailout solution” to a “standardised complimentary approach” in the treatment of (e.g. left upper extremity) can reduce the juxtarenal abdominal aortic aneurysm (AAA). stroke risk after ChEVAR procedures. In case of multiple chimneys, retrograde IN 2003, ROY GREENBERG AND in this patient group was 14.3% cannulation and periscope colleagues reported their first ChEVAR compared to 2.1% in cases with implantation of one or two experience in the Journal of Vascular 30% oversizing. A higher rate chimneys can be an alternative, Surgery. 1 This technique, originally born as a of gutter-related endoleaks and avoiding catheter manipulation at bailout solution for emergent situations, has low oversizing was found also the level of the aortic arch. Further grown in popularity in recent years. Different in patients treated in low volume studies are necessary to validate parallel graft methods (chimney/snorkel, centres (<20 patients treated per the technique. periscope, sandwich) have been developed year), showing that experience Giovanni Torsello for the treatment of complex infrarenal, plays an important role in the References juxtarenal, suprarenal, thoracoabdominal, outcome of this procedure.8 1. Greenberg RK, et al. Should patients with challenging anatomy be offered endovascular aneurysm repair? J Vasc and aortic arch pathologies.2 These off-the- Another important merit of the PERICLES Surg 2003; 38: 990–996. shelf solutions have been adopted in many study is the demonstration that the materials 2. Kansagra K, Kang J, Taon MC, et al. Advanced endografting techniques: snorkels, chimneys, periscopes, fenestrations, centres worldwide. However, the preliminary play a paramount role when avoiding gutters.9 and branched endografts. Cardiovasc Diagn Ther 2018; 8(Suppl 1): S175–S83. reported results were heterogeneous. Unpublished data presented at the LINC 3. Ohrlander T, Sonesson B, Ivancev K, et al. The chimney graft:

While Ohrlander, Hiramoto, and Donas3–5 Mount Sinai 2017 Endovascular Symposium a technique for preserving or rescuing aortic branch vessels in stent-graft sealing zones. Endovasc Ther 2008 Aug; 15(4): reported excellent outcomes in terms of (13–14 June, New York, USA) show that 427–32. doi: 10.1583/07-2315.1 30-day mortality and type I endoleak, higher the frequency of this complication was 3.4 4. Hiramoto JS. Commentary: Multiple chimney grafts for total endovascular revascularization of the visceral arteries morbidity and mortality have been described times greater in patients treated with stainless in the setting of ruptured TAAA: Inventive but let’s wait for by other authors.6 The reasons for diverging steel endoskeleton compared to nitinol the smoke to clear on this one. J Endovasc Ther 2010; 17: 222–223. results were the small number of patients devices. This finding was confirmed by the 5. Donas KP, Pecoraro F, Torsello G, et al. Use of covered chimney stents for pararenal aortic pathologies is safe included in single-centre cohorts, the wide PROTAGORAS study,10 showing excellent and feasible with excellent patency and low incidence of variety of treated entities, and the varying results if the flexible Endurant™ endograft 6. endoleaks. J Vasc Surg 2012; 55(3): 659–65. Coscas R, Kobeiter H, Desgranges P, Becquemin JP. device combinations used. (Medtronic) is combined with high-radial Technical aspects, current indications, and results of chimney

In order to better understand the value of force balloon-expandable chimney stent grafts for juxtarenal aortic aneurysms. J Vasc Surg 2011 Jun; 53(6): 1520–7. doi: 10.1016/j.jvs.2011.01.067. Epub 2011 the technique in different aortic pathologies, grafts (Advanta™ V12, Getinge). The data Apr 22. and also for standardisation of the procedure, have demonstrated the importance of specific 7. Donas KP, Lee JT, Lachat M, et al. Collected world experience about the performance of the snorkel/chimney endovascular thirteen European and American investigators device combinations to achieve good results, technique in the treatment of complex aortic pathologies: the PERICLES registry. Ann Surg 2015; 262(3): 546–53; pooled their experience with 517 cases not only in terms of endoleak reduction, but discussion 52–3. treated by ChEVAR in the PERICLES also in chimney occlusion-free survival. Both 8. Donas KP, Usai MV, Taneva GT, et al. Impact of aortic stent- graft oversizing on outcomes of the chimney endovascular registry. technique based on a new analysis of the PERICLES registry.

An initial point of concern was the high The ENCHANT 9. Vascular 2019; 27: 175–180. Scali ST, Beck AW, Torsello G, et al. Identification of optimal rate of intraoperative type Ia endoleak. In PERICLES,7 the type Ia endoleak rate registry will device combinations for the chimney endovascular aneurysm repair technique within the PERICLES registry. J Vasc Surg 2018; 68(1): 24–35. was 7.9% on completion angiography and decreased to 2.9% by the first postoperative computed tomography angiography (CTA), provide reliable data on ChEVAR 10. Donas KP, Torsello GB, Piccoli G, et al. The PROTAGORAS study to evaluate the performance of the Endurant stent graft for patients with pararenal pathologic processes treated by the chimney/snorkel endovascular technique. J Vasc Surg 2016; 63(1):1–7. demonstrating that the majority of ChEVAR gutter endoleaks can be expected to resolve performance.” 11. Taneva GT, Donas KP, et al. Results of chimney endovascular aneurysm repair as used in the PERICLES Registry to treat patients with suprarenal aortic pathologies. spontaneously. The evaluation of the J Vasc Surg 2020 May; 71(5): 1521–1527.e1. remaining persistent endoleaks were detected complications are rare when nitinol-polyester 12. Bosiers MJ, Tran K, Lee JT, et al. Incidence and prognostic factors related to major adverse cerebrovascular events in patients with an insufficient length of endografts are used. The choice of bridging in patients with complex aortic diseases treated by the chimney technique. J Vasc Surg 2018; 67(5): 1372–9. the new proximal seal zone. Another key stent is also important in order to reduce factor associated with a high risk of type additional use of relining stents, which is Giovanni Torsello is a vascular surgeon Ia endoleak was stent graft oversizing of associated with significantly worse stent at the Institute for Vascular Research, St less than 20%.8 The type Ia endoleak rate patency (p=0.014). Franziskus Hospital in Münster, Germany.