Comparison of attachment site endoleak rates in Dacron versus native aorta landing zones after thoracic endovascular aortic repair.

Objective: Type I attachment site endoleaks are the most common cause for reintervention after thoracic endovascular aortic repair (TEVAR) and represent treatment failures. Deployment of endografts in segments of the aorta previously replaced with Dacron grafts may be associated with reduced type I endoleak due to mechanical stability and decreased potential for aortic remodeling. However, no study has rigorously examined endoleak rates in Dacron landing zones vs native aorta.

Methods: A retrospective analysis of a prospectively maintained database was performed to identify all patients undergoing TEVAR at a single referral institution between May 2002 and June 2012. Overall, 319 patients undergoing 345 procedures had at least one follow-up contrast-enhanced computed tomography scan to assess for postoperative type I endoleak. Attachment site landing zones were classified as native aorta, Dacron, or endograft if landed in a previously placed endograft. Patient characteristics and type I endoleak rates were compared among the three groups.

Results: Identified were 697 proximal or distal landing zones (native aorta, 599; Dacron, 79; and endograft, 19). Patients with at least one Dacron landing zone had higher rates of hypertension (P < .01), chronic obstructive pulmonary disease (P = .04), and prior aortic surgery (P < .01) and were more likely to have undergone complex hybrid repairs (P < .01). Cumulative type I endoleak rates were equivalent between the three types of landing zone (native aorta, 3.7%; Dacron, 2.5%; endograft, 0%; P = .44). Two type I endoleaks occurred with Dacron landing zones in the first tertile of TEVAR experience and with Dacron landing zone lengths of <2.5 cm. Evaluation of endoleak rates by tertile of experience demonstrated decreased type I endoleak rates in Dacron landing zones between the first and second/third tertiles of experience (13.3% vs 0%, P = .03) after a policy of using >4 to 5 cm (twice the device instructions for use) of Dacron overlap was initiated.

Conclusions: Endograft deployment within long-segment (landing zone length of >4-5 cm) Dacron represents a durable option for aortic repair and was associated with a 0% rate of type I endoleak. In cases of a borderline native aortic landing zone, a hybrid procedure to create an adequate Dacron landing zone may be warranted to decrease the risk of type I endoleak and treatment failure.