A new technique to enhance endovascular thoracoabdominal aortic aneurysm therapy--the sandwich procedure

Abstract

Thoracoabdominal aortic aneurysm (TAAA) is a life-threatening condition with a potentially high risk of rupture (46% to 74%) when left untreated. Mean elective surgical mortality rate is 6.6% at best, rising to 47% for emergency operations. Standard thoracic endovascular repair alone is not currently considered an adequate approach to treat TAAA because of the visceral arteries involved by the aneurysm sac. A hybrid procedure and other complex endovascular techniques (eg, chimney graft, fenestrated and side-branched modular endograft systems) have been developed, but results are still conflicting; the procedures are not feasible for all patients and cost is still a concern. The sandwich technique was developed to address these aneurysms and dissection that still cannot be repaired in a safe, efficient, and cost-wise manner. From October 2008 to March 2012, elective and/or emergency sandwich technique repair was undertaken in 15 consecutive patients (80% male, mean age 70.3 years) with TAAA at our institution, with a mean follow-up period of 16.2 (range 1 to 36) months. Technical success rate was 92.3% and, in one patient (TAAA), both renal arteries could not be cannulated by guide wire and the procedure was aborted. Total, elective, and emergency 30-day mortality rates were 20% (3/15), 7.7% (1/13), and 100% (2 of 2), respectively. Two other deaths were unrelated to the procedure and due to hemorrhagic stroke (10 months) and lymphoma (12 months). Forty-eight visceral arteries (mean 3.4 arteries/patient) were successfully endorevascularized (22 renal arteries, 14 superior mesenteric arteries and 12 celiac trunks) with self-expandable covered stents and bare stents inside it in 14 patients. Three right and two left renal arteries could not be cannulated (5 of 54), comprising 9.2% failure to treat target vessels. Primary patency rate was 97.9%, with only 1 of 48 with endorevascularized target vessel occlusion. No spinal cord ischemia events were observed during the follow-up period. Three transient renal function impairments (20%) and one type III endoleak (11%), which sealed spontaneously at the 1-month assessment, were detected. Sandwich technique for TAAA repair is a safe, well-tolerated, feasible alternative using ready-to-use endoprosthesis to provide efficient visceral revascularization in types I, II, III, and IV TAAAs. The sandwich technique appears to be a promising tool in the endovascular repair of TAAA, but more experience with the method is warranted.