Association of Plasma Branched Amino Acid with Surgical Adverse Events in Type A Aortic Dissection

Background: Type A aortic dissection (AAD) is associated with substantial perioperative mortality and morbidity. Methods: We conducted a study of the concentrations of plasma amino acid metabolites by ultraperformance liquid chromatography mass spectrometry to identify patients at high risk of major adverse events (MAEs) in-hospital in 391 patients undergoing surgical repair, including 111 participants in a retrospective discovery set and 280 patients in a prospective validation set. Results: In the discovery set, 31 patients (27.9%) experienced MAEs in hospital, of whom 4 (12.9%) died. Metabolite factor 3, composed of branched-chain amino acids (BCAA), including valine, isoleucine, and leucine, was associated with MAEs. Median BCAA levels in patients with and without MAEs were 267.18 pg/mL (222.06-312.93 pg/mL) and 236.72 pg/mL (200.19-274.62 pg/mL), respectively. The adjusted odds ratio (OR) for increasing tertiles of BCAA compared with the lowest tertiles was 3.259 (95% confidence interval (CI) 1.018-10.431; P = 0.047). In the validation set, the adjusted OR for the increasing tertiles of BCAA compared with the lowest tertiles was 5.82 (95% CI 2.74-12.38; P < 0.001), indicating a significant association between the preoperative BCAA levels and outcome. Conclusions: Our study shows that in patients with AAD, the pre-operative plasma BCAA level was associated with the risk of post-operative adverse events of AAD in hospital. Funding Statement: This study was supported by the Ministry of Science and Technology of China (Key Projects of Precision Medicine Program, grant no. 2016YFC0903000 and 2017YFC0908400) and the Beijing Municipal Science and Technology Commission (Z171100000417002), NSFC (Natural Science Foundation of China) (81870341) Declaration of Interests: On behalf of all authors, the corresponding author states that there is no conflict of interest. Ethics Approval Statement: The study was designed as an observational study, including consecutive patients undergoing surgical repair for nontraumatic AAD (from July 2016 to November 2018) in the DPANDA registry study for aortic aneurysm and/or dissection (NCT03233087 in ClinicalTrials.gov), which was approved by the Beijing Anzhen Hospital Ethics Review Board. All patients provided written informed consent.