Safety of Patient Stratification Based on Initial Imaging Follow-up After Endovascular Aneurysm Repair (EVAR)

Abstract

Introduction: Most patients undergo uneventful long-term follow-up after EVAR. Therefore, unmodified surveillance protocols may be ineffective. Recently, modified follow-up protocol was suggested by the European Society for Vascular Surgery (ESVS). One feature of this protocol is that for patients without any detectable complication at one month or at one year, the next scheduled follow-up could be carried out at five years. In this study, we analysed the safety of this protocol retrospectively by evaluating the fate of the patients if they had been followed according to the introduced protocol. Methods: Between 2005 and 2013, 346 patients were treated electively for abdominal aortic aneurysm (AAA) in an academic center. Indication for treatment was an AAA ≥5.5cm in men and ≥5.0cm in women or growth (≥5mm) during the previous six months. Patients were treated with three different stent grafts: Zenith by Cook, Excluder by Gore and Endurant by Medtronic. All patients were annually followed according to prearranged program including CTA at 1 and 24 moths and CDUS annually. Available control images until the end of 2018 were retrospectively analysed for the study. Results: The mean follow-up was 68 months (range, 0- 153 months) and overall survival was 93.4%, 84.1%, 65.0%, 21.4% at 1, 2, 5 and 10 years. 30-day mortality was 1.2% (n=4). Imaging data for those surviving the first 30 days was available for 98.8% (n=338) subjects. At one-month control exam 82.0% (n=277) patients had no detectable endoleak. Of those patients 11.1% (n=31) developed re-intervention requiring graft-related complication during the next five years (Figure 2, 1). Among these incidents were four RAAAs. Among those with an endoleak type 2 at one month (n=56), six had sac shrinkage at one year CDUS and therefore the next surveillance control would have been at five years. Four out of these six patients developed re-intervention requiring graft-related complication between 1 and 5 years, including one RAAA (Figure 2, 2). Complications requiring treatment that would have been missed by following the suggested protocol included: endoleak type 1A (n=9), endoleak type 1B (n=7), endoleak type II (n=19), thrombosis (n=4), and RAAA (n=5). In general 22.0% (n=76) of the patients had re-intervention requiring complication and 80.0% (n=61) of them were treated during the first five years after EVAR. The sensitivity and specificity of one month CTA to detect potential significant complications during the first five years were 47.5% (95% CI 32.3-60.9%) and 88.2% (95% CI 83.8-91.7%) respectively. Conclusion: According to our study, most re-intervention requiring complications after EVAR occur in early postoperative years. Further, in our cohort the sensitivity of one month CTA to detect potential significant complications during the first five years is low, 47.5 %. Therefore, surveillance should be more frequent during the early years after EVAR and patient-modified surveillance should probably be considered later in the course of follow-up.Figure 2Retrospectively analysed 346 EVAR patients placed in recommended algorithm during first five years of follow-up.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Disclosure: Nothing to disclose