Operative Times and Outcomes of Complex Endovascular Repairs of Thoracoabdominal Aneurysms

Abstract

IntroductionOwing to the significant morbidity and mortality of open thoracoabdominal aortic aneurysm surgery, complex endovascular repairs (eTAAA) have become increasingly common, but still carry substantial risk. These repairs require large bore access, with resultant pelvic and lower extremity ischemia. We therefore hypothesized that operative timing would be associated with outcomes, as efficient surgery would limit the ischemic time as well as anesthesia time. MethodsWe studied all eTAAA repairs (Crawford Types 1-3, 5) incorporating at least one branch vessel from 2014 to 2021 in the Vascular Quality Initiative, and categorized them into quartiles of total operating time. To account for variations in case complexity and intraoperative events, we performed a sub-analysis stratifying each surgeon by their median operating time. Multilevel logistic regression was employed to compare perioperative outcomes including mortality, thoracoabdominal life altering events (TALE:composite of perioperative death, stroke, permanent paralysis and/or dialysis), spinal cord ischemia (SCI), acute kidney injury (AKI), major adverse cardiac events (MACE), myocardial infarction, and dialysis. ResultsThere were 2,925 eTAAA repairs during the study period. Procedure times ranged from <204 minutes in the first quartile to >365 minutes in the fourth. Longer cases more commonly involved older patients who were more often female, and higher rates of prior stroke, and preoperative anemia. They involved larger, more extensive aneurysms, with higher rates of prior aortic surgery, and more commonly employed PMEGs or parallel grafting to incorporate more branch vessels. In addition, they were less often staged procedures, and used more spinal drains, femoral cutdowns, and upper extremity access. Operating time decreased as experience increased. In adjusted analyses, the odds of mortality and every morbidity studied increased stepwise with operating time, with 4 to 13-fold higher odds in the highest quartiles. Spinal cord ischemia had the strongest association with procedure times, with seven-fold higher odds (OR 7.2 [2.9-17.9], P<.001) of any SCI in the highest quartile compared to the lowest, and 13-fold higher odds of permanent SCI (OR 13.1 [3.9-44.7], P<.001). These results were consistent when surgeons were grouped into quartiles by their median operating times. Medium-term mortality was also higher in the upper quartile of operating time (HR 2.7 [1.4-5.1], P=.002). ConclusionLonger operating times for complex eTAAA repairs were associated with markedly higher rates of morbidity and mortality, especially spinal cord ischemia. These results emphasize the importance of expeditious repairs by experienced teams.