Correlative effect between sac regression and patient longevity following endovascular solution for abdominal aortic aneurysms: an international analysis

Introduction: Since the introduction of endovascular aortic repair (EVAR) it has become the mainstay treatment for abdominal aortic aneurysms. Several EVAR devices exist commercially, yet, the Terumo Aortic Fenestrated Anaconda(TM) endograft has demonstrated outstanding results. Evidence in the literature suggests that sac regression could be linked to patient survival and longevity. The main scope of this study is to evaluate sac regression and survival achieved using the Fenestrated AnacondaT endograft and to discuss relevant literature. Materials and methods: The current study represents a nine-year cross-sectional international analysis of custommade Fenestrated Anaconda(TM) device. For the statistical analysis, SPSS 28 for Windows and R were utilised. Pearson chi-square analysis was used to assess differences in cumulative distribution frequencies between select variables. Statistical significance for all two-tailed tests was set at p < 0.05. Results: A total of 5,058 patients received the Fenestrated Anaconda(TM) in this study, either due to unsuitable/complex anatomy for competitor devices (n= 3,891) or based on surgeon preference (n= 1,167). A sac regression of 0-30% was observed in 4,772 (94.3%) over the first four years post-EVAR. Here, 99.6% of patients receiving the Fenestrated Anaconda(TM) due to unsuitable/complex anatomy for competitor devices and 76.8% based on surgeon preference had 0-30% sac regression. During years 5-9 of follow-up, all patients had 20-45% sac regression. Patient survival during the first six years post-EVAR was 100% but dropped to 77.1% in years 7-9. Survival differed between categorical patient subsets based on the indication. Discussion: The Fenestrated AnacondaT has been proven to be a highly effective EVAR endograft. Evidence in the literature clearly demonstrates that sac regression is an accurate prognostic factor for patient survival and longevity.