Objective: Despite the increasing application of tolvaptan in cardiac surgery, there is no information on the use of tolvaptan in Stanford patients with type A aortic dissection. The objective of this study is to evaluate the clinical effect of tolvaptan in patients with type A aortic dissection after surgery.Methods: A retrospective analysis was performed on 45 patients treated for type A aortic dissection in our hospital from 2018 to 2020, including 21 patients who were treated with Group T and 24 patients who were not treated with Group L. Perioperative data were collected from the hospital's electronic records.Results: Patients receiving tolvaptan did not differ significantly from those on traditional diuretics in terms of the duration of mechanical ventilation, postoperative blood required, length of catecholamine use, or amount of diuretics received (all P> 0.05). The development of new atrial fibrillation was significantly less in the tolvaptan group (P=0.023). Urine volume was slightly, but non-significantly, higher in patients receiving tolvaptan. Serum levels of potassium, creatinine, and urea nitrogen did not differ between the groups in the week after surgery, while that of sodium was significantly higher in the tolvaptan-treated group on day 7 after transfer from the ICU (P=0.001). Sodium levels were also elevated by day 7 in patients receiving traditional diuretics (P=0.001). The serum creatinine and urea nitrogen levels were raised on both days 3 and 7 in both groups (both P<0.05).Conclusions: For patients after acute Stanford type A aortic dissection, both tolvaptan and traditional diuretics are effective and safe. Tolvaptan is more effective in reducing the incidence of postoperative atrial fibrillation. For patients following Acute Stanford A aortic dissection surgery, tolvaptan did not provide a greater advantage over loop diuretics in terms of fluid clearance, but it may reduce the incidence of postoperative atrial fibrillation.