COMPARISON OF TWO DIFFERENT TECHNIQUES FOR ISOLATED LEFT SUBCLAVIAN ARTERY REVASCULARIZATION DURING THORACIC ENDOVASCULAR AORTIC REPAIR

Introduction - Endovascular repair of distal aortic arch/descending thoracic aortic diseases (TEVAR) may require the intentional coverage of the left subclavian artery (LSA) to increase the proximal landing zone and secure the sealing of the aortic lesion. Coverage without revascularization of the LSA may lead to cerebrovascular events, spinal cord deficits or upper arm ischemia. Up to date, no guidelines exist reporting which type of intervention should be preferred to revascularized the LSA. The aim of our paper is to analyze the results the isolated LSA revascularization during TEVAR, comparing the carotid-subclavian by-pass (CSbp) and the “double barrel” technique (DB). Methods - This is a multicenter, observational descriptive study. Inclusion criteria was TEVAR with isolated LSA revascularization. This experience includes patients observed from January 2012 to December 2016; for the final analysis, the end of study was December 31st 2016. All patients underwent follow-up program with computed-tomography angiography evaluation at 1, 6 and 12 months, on yearly basis thereafter. Primary end-points were early and long-term survival, LSA graft patency, freedom from TEVAR-related and aortic-related mortality (ARM), and freedom from reintervention. Categorical variables were presented using frequencies and percentages, continuous variables were presented with mean  standard deviation (SD). Cumulative survival, freedom from ARM and freedom from reintervention rates were estimated using the Kaplan-Meier method with 95% confidence interval (CI). A P value < .05 was considered significant. Results - During the study period we performed 308 TEVARs: in 73 (24%) cases the LSA was intentionally covered. Revascularization was performed with CSbp in 42 (57.5%), and DB in 31 (43.5%). The two groups were comparable for demographic data, comorbidities, risk factors and type of aortic disease treated. Overall, primary technical success was 100%. The DB was more frequently used when LSA had an acute angle (47 ± 17 vs. 63.5 ± 20, P = .020) at its origin, and when the distance between the LSA and the ipsilateral vertebral artery was longer (48 ± 11 vs. 36 ± 12, P = .007). The two groups did not differ significantly in terms of major complications (CSbp 7 vs. DB 11; P = .112), and in-hospital mortality (CSbp 1 vs. DB 1; P = 1.0). At a mean follow-up of 24 ± 20 mesi (range, 3-72), no LSA graft thrombosis was observed; the two groups did not differ significantly in terms of ARM (CSbp, 97 ± 3 vs. DB, 96 ± 4, log-rank = .868), need of aortic reintervention (CS 2 vs. DB 2; P = .836), or endoleak development (CSbp 2 vs. DB 1; P = .695). Conclusion - In our experience, LSA revascularization was safe and effective with both the techniques; at mid-term, both techniques offered durable results with no graft thrombosis.