Impact of Recovery from Acute Kidney Injury After Aortic Arch Repair

BACKGROUND The impact of recovery from acute kidney injury (AKI) after open thoracic aortic surgery on follow-up outcomes is unclear. METHODS This retrospective study included 214 patients who underwent aortic arch surgery requiring hypothermic circulatory arrest between 2007 and 2019. Patients who required preoperative renal replacement therapy and patients who died within 7 postoperative days were excluded. The incidence of recovery from AKI was examined. Renal outcomes were compared among patients with no AKI (Group N), recovery from AKI (Group R), and persistent AKI (Group P). RESULTS Preoperative kidney function was similar among the 3 groups. Among the 115 patients who developed postoperative AKI, 80.9% recovered from AKI at discharge. The 5-year cumulative mortality rate was 18.0%, 24.5%, and 68.4% in Group N, R, and P, respectively (P < .001, Group R vs Group P). The 5-year cumulative incidence of renal replacement therapy dependency was 0.0%, 5.4%, and 22.7%, respectively (P = .04, Group N vs Group R; P = .01, Group R vs Group P). The medians (interquartile range) of estimated glomerular filtration rate (mL/min/1.73 m(2)) 2 years after surgery were 65.2 (50.4-80.2), 54.3 (41.4-65.9), and 56.9 (40.2-67.5), respectively (P = .03, Group N vs Group R). CONCLUSIONS The majority of patients recovered from AKI after thoracic aortic repair by discharge. However, the prolonged impact of AKI recovery on kidney function was observed during the follow-up period. Diligent follow-up after discharge is warranted for early identification of patients at high risk of kidney disease progression.