Aortic debranching from the ascending aorta: a novel surgical approach for extended TAAA and chronic type B...

Extend thoraco-abdominal aortic aneurysms (TAAA) involving arch vessels and the visceral arteries remains a challenging operation when affecting high risk patients (HRP). Recently, hybrid surgery has gained popularity for HRP. The conventional surgical repair is the gold standard for low risk patients with previous mortality from 6% to 15% in thoracic aneurysms up to 30% in thoracic type B dissections. The risk of paraplegia is 3% to 15%. Without repair the outcome is poor with only 35% of patient's survival at two years after diagnosis. The total endovascular technique is not widespread used because of its very time-consuming, needs training, and procedure planning with high radiation exposure. Only few centers in the world perform it. In order to reduce the morbidity a novel approach is proposed, with an aortic debranching from the ascending aorta.

Nine patients (two females) aged between 53 and 81 years, with high risk factors for surgery, were offered this hybrid technique from March 2004 to July 2009. Eight patients presented with a TAAA and one type a B chronic dissection. A staged hybrid operation started by a debranching of the aorta from a median sternotomy to supra-aortic vessels and visceral arteries, followed by the second stage one-two weeks later, with an extended stent grafting. This attitude avoids CPB and aortic cross clamping. The surgical approach is a median sternotomy combined to mid upper laparotomy associated to pericardial and diaphragm division. It is well tolerated even in elderly patients and allows easy access to celiac axis (CA), superior mesenteric artery (SMA), right renal artery (RRA). Access to the left renal artery is more difficult and may be benefit from a combinated stent grafting and bypass according to the VORTEC technique described by Lachat M, or an extra-anatomic bypass. Rerouting the visceral arteries is done from the ascending aorta with a partial clamping on an undiseased implantation site, offering à good anterograde high flow. Combined bypass to supraaortic vessels is associated when needed.

There was no intraoperative mortality. One patient died during 30D period from cardiac failure and another on the early follow up from a pancreatic fistula. The complications: one stroke (11.1%); one cardiac failure (11.1%); one renal failure (11.1%), one pancreatic fistula (11.1%), one non-infected retrostrenal collection (11.1%). No paraplegia, limb ischemia or aortic fistula were detected. No stent-graft related complication was retrieved, the bypass patency was 77.7 at four-year survival.

Our early and mid term results are promising and similarly to other series. This new approach for rerouting the supraaortic and visceral arteries before stent grafting in extended TAAA, lowers the surgical injury and is particularly designed for HRP who cannot benefit from conventional surgery under CPB. Larger series and longer follow-up are needed.