397. Long-term Clinical and Radiographic Outcomes in Patients with Isolated Aortitis

Background/Objectives: Around 2-12% of patients who undergo open thoracic aortic aneurysm repair are incidentally found to have aortitis on pathology. There is no standardized approach to the post-operative care of patients with incidentally-found aortitis nor extensive data on post-operative and long-term outcomes. A better understanding of the risk for recurrent vascular disease and surgical complications in this population could inform clinical surveillance and treatment. This study compared immediate post-operative and long-term outcomes between patients with pathology-diagnosed aortitis and those with non-inflammatory aortic aneurysms after undergoing open thoracic aortic aneurysm repair. Methods: This is a single-center matched cohort study. Patients with aortitis were identified by histopathology following open thoracic aortic aneurysm repair in the University of Pennsylvania Health System between 2007 and 2017 and lacked any evidence of infection or known prior diagnosis of rheumatic disease. Two comparators who lacked significant inflammation on pathology were matched to each aortitis case by year of surgical repair. Outcomes included length of hospital stay, surgical complications, formation of new vascular abnormalities on CT/MRI imaging, and death. Differences between groups were compared using conditional logistic, Cox proportional hazards, or conditional Poisson regression models accounting for matching. Results: 162 patients were included: 53 patients with aortitis and 109 matched comparators. Aortitis patients were more likely to be older, female and less likely to have a history of coronary artery disease. 93% of each group had an ascending thoracic aortic aneurysm that was repaired. There was no difference in hospital length of stay, post-operative complications, surgical revision or death between groups. While over 90% of patients in each group followed-up with their cardiothoracic surgeon, only 32% of patients with aortitis saw a rheumatologist in the outpatient setting and 33% received immunosuppressive treatment. On long-term surveillance imaging, no difference was seen in new or worsening aortic aneurysms between groups, but there were significantly more vascular abnormalities in the thoracic aortic branch arteries (carotid, subclavian, brachiocephalic, and celiac arteries) in the aortitis group (39% vs. 11%, P < 0.01)(Figure 1). Conclusions: Among patients who underwent open surgical repair of a thoracic aortic aneurysm, patients with incidentally-discovered aortitis were more likely than non-inflammatory comparators to develop vascular anomalies in major aortic branch arteries. The higher rate of arterial abnormalities in patients with aortitis may reflect ongoing inflammatory changes from an underlying vasculitic process and suggest that more frequent surveillance imaging and involvement of a rheumatologist are needed in the long-term care of these patients. Disclosures: Non