The Kissing Stent Technique in the Treatment of Aorto-iliac TASC C-D Lesions: Clincal and Anatomical Predictors of Patency

Abstract

Introduction - The endovascular treatment(EVT) of peripheral artery obstructive disease(PAOD) involving the aortic bifurcation is still a matter of debate in case of TASC-C and D lesions, since a complete revascularization of the entire aortic bifurcation is required. Aim of our work was to evaluate safety and efficacy of endovascular aortic bifurcation revascularization achieved with the kissing stent technique and analyze patency during the follow-up. Methods - All consecutive patients treated with aortic bifurcation kissing stenting (January 2012-December 2017) for aorto-iliac TASC-C and D PAOD were retrospectively analyzed. Anatomical features were reviewed at preoperative computed tomography angiography (CTA) to identify severe iliac calcifications (calcifications involving>75% of the circumferential diameter of the aorta and the common iliac arteries) and extensive aorto-iliac thrombosis (involving>75% of the aortic bifurcation diameter). Technical success(TS) was defined as the absence of>30% residual stenosis measured on angiographic images and other complications requiring reintervention. Primary(PP) and secondary(SP) patencies were analyzed during the follow-up performed by duplex ultrasound at discharge, 3, 6 months and yearly thereafter. Cox regression and Kaplan Meier analysis were performed to evaluate the long-term patency and possible risk factors. Results - Fifty-one(33.1%) patients fulfilled the inclusion criteria over a total of 154 aorto-iliac EVTs. Mean age was 66±1 years, 20(39.2%) were females. Risk factors: hypertension 94.1%, diabetes 41.1%, dyslipidemia 90.2%. Critical limb ischemia (Rutherford classification stages 4-6) was present in 22(43.1%) patients; 29(56.9%) had severe claudication (Rutherford 3). According to the preoperative CTA, TASC-C and D lesions were identified in 24(47%) and 27(53%) patients, and severe calcifications and extensive thrombosis in 55% and 45% of patients, respectively. Thirty-one patients(60.8%) received a dual antiplatelet therapy for at least 1 month after the procedure. TS was achieved in 49(96.1%) cases; in 2 patients, only one iliac axis was successfully revascularized due to technical reason, leaving the other surgically untreated. The kissing stenting technique was performed by balloon-expandable stent in 30(58.8%) cases, self-expandable stent in 12(23.5%) cases, and covered kissing stent in 9(17.6%) cases. In 28(54.9%) cases an extension of stenting in the external iliac artery was performed. At a mean follow-up of 38.5 months (1-78 range), PP and SP were 87±5% and 93±4%, respectively. Six iliac axis occluded during the follow-up, all within the first year after procedure and were revascularized in 3 cases(50%) with endovascular relining. Three other cases were left untreated due to the effective compensation achieved in the meantime. Among all the variables examined, only dual antiplatelet therapy delivery was associated with higher primary patency compared to single antiplatelet (96±4% vs 75±9%, P=.03), differentially severe aorto-iliac thrombosis was associated with lower primary patency (73±9 vs 96±4%, P=.03). The present results were confirmed also by Cox-regression analysis (HR: 0.14, 95%IC: 0.01-0.89, P=.05; HR: 6.8, 95%IC: 1.21-59, P=.05). Conclusion - EVT for aorto-iliac TASC C-D is an effective and safe technique. Iliac axis occlusion is rare and usually occurs within the first year after procedure in patients with no dual antiplatelet therapy. Severe preoperative thrombotic lesions are negative predictors of PP.