Thoracic endovascular aortic repair of metachronous thoracic aortic aneurysms following prior infrarenal abdominal aortic aneurysm repair

Objective: Thoracic endovascular aortic repair (TEVAR) of metachronous thoracic aortic aneurysms (M-TAAs) following previous infrarenal abdominal aortic aneurysm (AAA) repair has been associated with higher spinal cord ischemia (SCI) risk compared with TEVAR of primary thoracic aortic aneurysms (TAAs). However, data on the impact of the type of prior infrarenal aortic repair on outcomes are scarce. In this study, we examined perioperative outcomes and long-term mortality following TEVAR M-TAA compared with primary TEVAR of TAA. Methods: We identified all Vascular Quality Initiative (VQI) patients who underwent TEVAR of TAA in the descending thoracic aorta from 2013 to 2022. Only patients undergoing primary TEVAR or TEVAR following infrarenal open (OAR) or endovascular (EVAR) repair were included. We performed univariate analyses to identify differences in baseline and procedural characteristics, and multivariable analyses for perioperative outcomes and 5-year mortality using logistic and Cox regression, respectively. Results: We included 1493 patients who underwent primary TEVAR (81%) or TEVAR following prior OAR (9.0%) or prior EVAR (9.7%). Compared with primary TEVAR, patients undergoing TEVAR M-TAA were older, more commonly male, white, and had higher rates of hypertension, smoking, and renal dysfunction. Patients with M-TAA were more likely to be asymptomatic and have larger diameters at presentation but were exposed to greater contrast volume and procedural times relative to primary TEVAR patients. Following risk-adjustment, compared with primary TEVAR, TEVAR after prior EVAR was associated with higher perioperative mortality (9.7% vs 3.9%; odds ratio [OR], 5.3; 95% confidence interval [CI], 2.3-12; P < .001) and 5-year mortality (40% vs 24%; hazard ratio [HR], 2.1; 95% CI, 1.4-3.1; P = .001). Specifically, among octogenarians (n = 375; 25%), the perioperative and 5-year mortality differences were even more pronounced (perioperative mortality: 17% vs 8.4%; OR, 6.7; 95% CI, 2.2-21; P = .001; 5-year mortality: 50% vs 27%; HR, 3.0; 95% CI, 1.5-5.7; P = .010). However, in-hospital complications, including SCI (2.6% vs 2.8%; OR, 1.2; 95% CI, 0.33-3.3; P = .77), were not notably different. In contrast, TEVAR after previous OAR was associated with comparable perioperative mortality (4.4% vs 3.9%; OR, 1.2; 95% CI, 0.32-3.8; P = .73), 5-year mortality (28% vs 24%; HR, 1.3; 95% CI, 0.80-2.1; P = .54), and in-hospital complications, including SCI (2.6% vs 0.7%; OR, 0.21; 95% CI, 0.01-1.1; P = .16). Conclusions: Patients undergoing TEVAR of M-TAAs after prior EVAR, particularly octogenarians, have higher perioperative and 5-year mortality and therefore, represent a high-risk group. Future efforts should strive to discern the underlying factors leading to these poorer outcomes; meanwhile, these findings emphasize the need for careful patient selection and appropriate preoperative counseling in these high-risk individuals.