Factors associated with sac regression after F/BEVAR for complex abdominal and thoracoabdominal aneurysms

The behavior and remodeling of the residual aneurysm sac after endovascular repair is predictive of long-term outcomes. Although persistent growth is clearly a harbinger of complications, only recently has the relative advantage of sac regression over sac stability been recognized. There is a growing literature examining the prognostic implications of sac regression after standard infrarenal endovascular aortic repair, and various factors associated with increased likelihood of regression have been identified. However, there is a relative paucity of data on sac regression after more complex aneurysm repairs using fenestrated and/or branched technology. In this article, we aim to review sac regression and its importance as a whole, and specifically examine the role of regression after fenestrated and/or branched endovascular aortic repair for more extensive abdominal and thoracoabdominal aneurysms.