Effect of Levosimendan Use on All-Cause Mortality in Out-of-Hospital Cardiac Arrest Survivors After Extracorporeal Cardiopulmonary Resuscitation

<b>Background:</b> Survivors of out-of-hospital cardiac arrest (OHCA) after external cardiopulmonary resuscitation (ECPR) have a mortality rate as high as 50-70%. The use of vasoactive inotropes worsen the mortality rate at admission. The administration of levosimendan within 72 h of ECPR facilitates extracorporeal membrane oxygenation (ECMO) weaning, so it is important to determine whether levosimendan improves mortality. <b>Methods:</b> This retrospective cohort study included 158 patients with OHCA of cardiac origin who had undergone ECPR and were hospitalized between January 2015 and December 2024. This study was conducted in the intensive care unit of China Medical University Hospital, Taichung, Taiwan. Twenty-three patients received levosimendan within 72 h, whereas the others did not receive levosimendan. Primary endpoints included ECMO weaning failure rate and 90-day all-cause mortality rate. Kaplan-Meier survival curve analysis was also performed. Covariates for all-cause mortality were estimated and adjusted by using Cox regression modeling. <b>Results:</b> The levosimendan group exhibited lower rates of ECMO weaning failure and 90-day all-cause mortality than the control group (13.0% vs. 52.6% and 17.4% vs. 57.0%, respectively; both <i>p</i> < 0.001). The 90-day survival curve analysis revealed that the levosimendan and control groups had survival rates of 82.6% and 43.0%, respectively (log-rank <i>p</i> < 0.001). Administration of levosimendan within 72 h resulted in a odds ratio of 0.36 (95% confidence interval: 0.18-0.79, <i>p</i> = 0.01). <b>Conclusions:</b> Administering levosimendan within 72 h of ECPR could be a protective factor in improving all-cause mortality.