The Chimney Technique in Endovascular Aortic Aneurysm Repair: Late Ruptures After Successful Single Renal Chimney Stent Grafts

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

“…Consequently, broad and mixed use of parallel grafts without any previous testing can lead to primary feasibility but a remarkable secondary complication rate with occurrence of chimney occlusions and late aortic ruptures. 11 Publications of these inhomogeneous and untested combinations performed mainly in small cohorts of about 10 patients and with inclusion of mixed pathologic processes (thoracoabdominal aneurysms, dissections, aortic occlusions, and pararenal diseases) 12 are not representative of the performance of the chimney technique generally, and they reflect only institutional results with the local use of off-the-shelf devices.…”

“…Use of various combinations, including stent grafts with suprarenal vs infrarenal fixation, nitinol vs stainless steel skeleton, and balloon-expandable or self-expanding covered chimney stents, shows broad feasibility of the chimney technique. On the other hand, the mixed and multifaceted device combinations are linked to significant different incidence of gutter-associated endoleaks and chimney graft occlusions, leading to enthusiastic reports on one side [3][4][5][6][7][8] and pessimistic criticisms 11,12 on the opposed side. Consequently, there is a substantial need for a profound and objective evaluation of the chimney technique, and that can be done only in the case of standardized device combinations and follow-up protocols; the conduction of a randomized controlled trial with other endovascular techniques, such as fenestrated endografting, is difficult because of the different patient cohorts.…”

Endovascular Chimney Technique for Juxtarenal Abdominal Aortic Aneurysm: A Systematic Review Using Pooled Analysis and Meta-Analysis

“…Of these 20 endoleaks, 12 type I endoleaks were considered as ''low flows,'' which appeared after some delay 26 and finally disappeared during follow-up. 1,14,18,21,24 The ''kissing balloon'' technique, 13 Palmaz stent (Cordis, Miami Lakes, FL), 1 proximal coil embolization or extender cuff placement 18,20 were successfully used to resolve the other 8 type I endoleaks (Table IV). A total of 13 patients (5.5%) developed type II endoleaks within 30 days without death.…”

Impact of Renal Chimney Grafts on Anatomical Suitability for Endovascular Repair in Ruptured Abdominal Aortic Aneurysm

“…Even in the absence of dedicated devices, the applicability and indications for the CG technique are expanding ( Figure 19) and it is often used for the extremely difficult and urgent cases or when other advanced alternatives, including OR, either fails or is deemed too risky (Criado 2007, Schiro et al 2013. In many countries, the cost of fEVAR or bEVAR has been prohibitive, which made the CG technique the only possible therapeutic option for many patients (Zhang et al 2012, Guo et al in press).…”