Transrenal Endovascular Aneurysm Repair–A Novel Approach for Abdominal Aortic Aneurysms with Difficult Neck Anatomy

Abstract

The endovascular approach to treating ruptured or symptomatic abdominal aortic aneurysms (AAA) with difficult neck anatomy still poses a major challenge. This study proposes and evaluates the outcomes of a novel technique, Transrenal Endovascular Aneurysm Repair (Tr-EVAR) which utilizes the top ring 'valley' and 'peak' configuration of the Anaconda stent graft to achieve proximal seal in AAAs with an unfavourable neck. All patients treated with Tr-EVAR over a period of 10 years were identified retrospectively. Demographic, clinical and outcome data were collected, and survival analysis was performed. The time-to-event was analysed using Kaplan-Meier curves for complication-free survival, reintervention-free survival, and overall survival. During the study period, 36 patients ruptured, symptomatic or large AAAs having unfavourable necks and not fit for open repair underwent Tr-EVAR. Two patients died in the first 30 days post-procedure (5.6%). The overall survival at 1 year, 3 years and 5 years were 86%, 72% and 54% respectively with a mean overall survival of 74.0 months (SE 7.8, 95% CI 58.7 - 89.3) which was comparable to chimney EVAR. The complication-free survival and reintervention-free survival at 1 year, 3 years,5 years were 75%, 61%, 42% and 78%, 64%, 45% respectively. Tr-EVAR can be considered as an off-the-shelf solution for urgent cases not fit for open repair with unfavourable neck features for standard EVAR. Careful patient selection and planning have generated acceptable immediate, mid-and long-term results comparable to those presented by chimney EVAR in the literature.