Impact of Discordant Views in the Management of Descending Thoracic Aortic Aneurysm

Abstract

Thoracic endovascular aortic repair has a lower perceived risk than open surgical repair and has become an increasingly popular alternative. Whether general consensus exists regarding candidacy for either operation among open and endovascular specialists is unknown. A retrospective review of isolated descending thoracic aortic aneurysm at our institution between January 2005 and October 2015 was performed, excluding trauma and dissection. Two cardiac surgeons, 2 cardiovascular surgeons, 1 vascular surgeon, and 1 interventional radiologist gave their preference for open vs endovascular repair. Interobserver agreement was assessed with the kappa coefficient. k-means clustering agnostically grouped various patterns of agreement. The mean rating was predicted using least absolute shrinkage and selection operator regression. Negative binomial regression predicted the discrepancy between our panel of raters and the historical operation. Generalized estimating equation modeling was then used to evaluate the association between the extent of discrepancy and the adverse perioperative outcome. There were 77 patients with preoperative imaging studies. Pairwise interobserver agreement was only fair (median weighted kappa 0.270 [interquartile range 0.211-0.404]). Increasing age and proximal neck length predicted an increasing preference for thoracic endovascular aortic repair in our panel; larger proximal neck diameter predicted a general preference for open surgical repair. Increasing proximal neck diameter predicted a larger discrepancy between our panel and the historical operation. Greater discrepancy was associated with adverse outcome. Substantial disagreement existed among our panel, and an exploratory analysis of the effect of increasing discrepancy demonstrated an association with adverse perioperative outcome. An investigation of the effect of a thoracic aortic team with open and endovascular specialists is warranted.

Keywords: TEVAR; aneurysm; aorta; inter-observer agreement; statistics.