Two-year results of chimney grafts show excellent stent graft patency and stable/shrinking aneurysms


Konstantinos P Donas, Clinic for Vascular and Endovascular Surgery, Münster University Hospital and St Franziskus Hospital, Münster, Germany, and colleagues have found that the use of chimney and/or periscope endografts for pararenal aortic pathologies achieves and maintains successful exclusion of aneurysms in 90% of the cases at 24 months of radiological follow-up.

The study, recently published in the Journal of Endovascular Therapy, provides some of the longest term results available for this procedure.

Donas et al noted that the chimney graft technique is used to “ensure secure proximal fixation and to increase the applicability of endovascular repair for patients with pararenal aortic pathologies.”  In this technique, the authors said “a covered or bare metal stent is deployed parallel and outside of the aortic endograft, inflow upward (i.e., periscopes) or downward (i.e., chimneys), to retain or rescue blood flow into aortic branches along the sealing zones.”

According to Donas et al, so far, only short-term results have been available regarding the success of this technique. While those results have been good, more information is needed before declaring this novel technique a success. The current study provides midterm results, following patients who underwent the procedure at least two years earlier.

In the study, 124 high-risk patients with pararenal aortic pathologies were treated between January 2008 and December 2011 at two European vascular and cardiovascular centres with advanced experience in the chimney graft technique. Of the 124 patients treated at these centres, 40 completed computed tomographic angiography (CTA) follow-up at 24 months after the procedure to determine the stability of the chimney stents. Those patients were the subject of this study.

At two years after treatment, significant shrinkage (>5 mm; n=22) or stable aneurysm diameter was seen in 90% (36) of the cases. The overall technical success was 100%, and the early- and midterm procedure-related mortality was 0%.

Overall, mean aneurysm sac shrinkage was 12% (p=0.002) and 10% (p=0.014) for the two centres, respectively (overall p=0.008). There were no aneurysm ruptures in follow-up.

An accompanying commentary by Felix JV Schlösser and Bart EMuhs, both from the Section of Vascular Surgery, Department of Surgery, Yale University School of Medicine, Yale-New Haven Hospital, New Haven, USA, welcomes this news, calling it the “most significant contribution of midterm results after chimney aortic repair … to date.” The authors point out that the 40 patients treated at the first centre have now successfully passed a mean time of more than 2-1/2 years since their procedure. They also commented: “Long-term data are needed to provide more information regarding safety and durability and to improve treatment and follow-up strategies, which could further accommodate developments in this field and lead to an improved prognosis for patients with aortic disease.”