Discussion
myocardial injury, organ dysfunction
SECONDARY, MYOCARDIAL ISCHEMIA
In this rigorous, international trial of high-risk cardiac surgical patients undergoing complex procedures, high-dose selenium supplementation compared with placebo did not increase the number of days alive and without persistent organ dysfunction over the 30 days after cardiac surgery. No differences between groups were found for 30-day mortality, 6-month mortality, ICU length of stay, hospital readmission, daily rates of persistent organ dysfunction or frequencies of life-supportive therapies, or any other key secondary outcomes. Additional secondary outcomes demonstrated that fewer patients had a readmission to an ICU in the selenium group compared with the placebo group. Yet, these findings favoring high-dose selenium administration should be interpreted with caution and as hypothesis generating only as there was no adjustment made for multiple tests of significance and this finding could be a type I error.Observational studies demonstrate that myocardial ischemia, reperfusion time, and duration of CPB are associated with a decrease of intraoperative selenium levelsPreliminary evidence received from smaller studiesThere are several potential reasons for our neutral trial result, which differs from previous studies. Notably, our trial was the first and only multinational and multicenter study with an adequate sample size to determine if differences existed, to our knowledge. Studies with lower statistical power reporting significant treatment effects are less likely to be true positive and overestimate the size of the effect.Furthermore, recent innovations in surgical myocardial preservation techniques, such as combined antegrade and retrograde myocardial perfusion alone during bypass, are associated with smaller perioperative myocardial injury, which makes it challenging to demonstrate additional clinical benefits.