Early results of left carotid chimney technique in endovascular repair of acute non-a-non-B aortic dissections.

PURPOSE

To report our early experience with endovascular repair of acute non-A-non-B aortic dissections using chimney grafts to preserve blood flow to a left common carotid artery (LCCA) located in the proximal landing zone.

METHODS

From June 2009 to May 2010, 8 patients (7 men; mean age 49 years, range 29-75) with acute non-A-non-B aortic dissection and no adequate proximal sealing zones underwent thoracic endovascular aortic repair (TEVAR). Covered stents were placed parallel to the aortic stent-grafts to restore flow to the LCCAs while extending the proximal fixation zones; the left subclavian arteries were intentionally covered after carefully cerebrovascular assessment. Follow-up examinations included computed tomography (CT) at 2 weeks, 3 months, 6 months, 12 months, and yearly thereafter.

RESULTS

All the procedures were completed successfully, with one main aortic stent-graft deployed and one chimney graft implanted in the LCCA. Two retrograde type II endoleaks identified intraoperatively were left untreated but followed closely using CT. There were no instances of puncture site complications, stroke, paralysis, or death during the hospital stay. The 30-day mortality was 0%. During the mean 11.4-month follow-up (range 6-15), there was no mortality, and duplex ultrasound and CT showed patency of all stent-grafts, enlargement of the true lumen, and compression of the false lumen. One type II endoleak disappeared in 2 weeks postoperatively, while the other gradually faded until it was nearly gone at 11 months postoperatively. During follow-up, no renal insufficiency, new late endoleaks, endograft migration, fracture, stent-graft related complications, or deaths were observed.

CONCLUSION

In short-term follow-up, TEVAR combined with the chimney technique seems promising for aortic dissections that involve the aortic arch with inadequate proximal sealing zones. More cases and long-term results are needed to evaluate the safety and efficiency of this alternative endovascular technique.