RT Journal Article SR Electronic T1 Perioperative urinary thromboxane metabolites and outcome of coronary artery bypass grafting: a nested case-control study JF BMJ Open JO BMJ Open FD British Medical Journal Publishing Group SP e021219 DO 10.1136/bmjopen-2017-021219 VO 8 IS 8 A1 Hanning Liu A1 Zhengxi Xu A1 Cheng Sun A1 Qianlong Chen A1 Ning Bao A1 Wen Chen A1 Zhou Zhou A1 Xiaoqi Wang A1 Zhe Zheng YR 2018 UL http://bmjopen.bmj.com/content/8/8/e021219.abstract AB Objective As a marker of in vivo thromboxane generation, high-level urinary thromboxane metabolites (TXA-M) increase the occurrence of cardiovascular events in high-risk patients. To investigate whether perioperative urinary TXA-M level is associated with major adverse cardiac and cerebrovascular events (MACCE) after coronary artery bypass graft (CABG) surgery, we designed a nested case-control study.Design Observational, nested case-control study.Setting Single-centre outcomes research in Fuwai Hospital, Beijing, China.Participants One thousand six hundred and seventy Chinese patients undergoing CABG surgery from September 2011 to October 2013.Methods We obtained urinary samples from 1670 Chinese patients undergoing CABG 1 hour before surgery (pre-CABG), and 6 hours (post-CABG 6 hours) and 24 hours after surgery (post-CABG 24 hours). Patients were followed up for 1 year, and we observed 56 patients had MACCE. For each patient with MACCE, we matched three control subjects. Perioperative urinary TXA-M of the three time spots was detected in these 224 patients.Results Post-CABG 24 hours TXA-M is significantly higher than that of patients without MACCE (11 101vs8849 pg/mg creatine, P=0.007). In addition, patients in the intermediate tertile and upper tertile of post-CABG 24 hours urinary TXA-M have a 2.2 times higher (HR 2.22, 95% CI 1.04 to 4.71, P=0.038) and a 2.8 times higher (HR 2.81, 95% CI 1.35 to 5.85, P=0.006) risk of 1 year MACCE than those in the lower tertile, respectively.Conclusions In conclusion, post-CABG 24 hours urinary TXA-M elevation is associated with an increase of 1 year adverse events after CABG, indicating that the induction of cyclo-oxygenase-2 by surgery-related inflammatory stimuli or platelet turnover may be responsible for the high levels of post-CABG urinary TXA-M.Trial registration number NCT01573143.