The relationship between false-lumen area ratio and renal replacement therapy after acute aortic dissection repair on bilateral artery cannulation: a cross-sectional study

BACKGROUND: Malperfusion poses a serious challenge to organ function in the repair of acute aortic dissection (AAD). The purpose of this study was to explore the segment change of false-lumen area ratio (FLAR; the ratio of the maximal false-lumen area to the total lumen area) in the descending aorta and its relationship with renal replacement therapy (RRT) after total aortic arch (TAA) surgery. METHODS: A total of 228 patients with AAD who received TAA using perfusion mode right axillary and femur artery cannulation between March 2013 and March 2022 were included in a cross-sectional study. The descending aorta was divided into 3 segments: the descending thoracic aorta (S1), the abdominal aorta above the ostium of the renal artery (S2), and the abdominal aorta between the ostium of the renal artery and the iliac bifurcation (S3). The primary outcomes were postoperative segmental FLAR changes in the descending aorta, which were observed using computed tomography angiography before the patients were discharged from the hospital. The secondary outcomes were RRT and 30-day mortality. RESULTS: The total potencies in the false lumen were 71.1%, 95.2%, and 88.2% in S1, S2, and S3. The postoperative/preoperative ratio of the FLAR was higher in S2 than that in S1 and S3 (S1: 67%±14%; S2: 80%±8%; S3: 57%±12%; all P values <0.001). For the patients undergoing RRT, there was a higher postoperative/preoperative ratio of the FLAR for the S2 segment (85%±7% vs. 79%±8%; P<0.001) and higher mortality (28.9% vs. 7.7%; P<0.001) after AAD repair compared with patients in the no-RRT group. CONCLUSIONS: This study demonstrated there was less attenuation of the FLAR on the abdominal aorta above the ostium of the renal artery in the whole descending aorta after AAD repair with intraoperative right axillary and femur artery perfusion mode. The patients needing RRT were associated with less postoperative/preoperative change of the FLAR and worse clinical outcomes.