Levosimendan versus Milrinone for Inotropic Support in Pediatric Cardiac Surgery: Results from a Randomized Trial

Abstract

Objective : We aimed to determine the differential effects of intra-operative administration of milrinone versus levosimendan on myocardial function after pediatric cardiac surgery. Transthoracic echocardiography was employed for myocardial function evaluation, utilizing biventricular longitudinal strain with two-dimensional speckle tracking echocardiography in addition to conventional echocardiographic variables. Design : A secondary analysis of a randomized, prospective, double-blinded clinical drug trial Setting : Two pediatric tertiary university hospitals Participants : Infants between 1-12 months of age diagnosed with ventricular septal defect, complete atrioventricular septal defect, or tetralogy of Fallot who were scheduled for corrective surgery with cardiopulmonary bypass. Interventions : The patients were randomized to receive an infusion of milrinone or levosimendan at the start of cardiopulmonary bypass and for 26 consecutive hours. Measurements and main results : Biventricular longitudinal strain and conventional echocardiographic variables were measured preoperatively, on the first postoperative morning and prior to hospital discharge. The association between perioperative parameters and postoperative myocardial function was also investigated. Images were analyzed for left ventricular (n=67) and right ventricular (n=44) function. The day after surgery, left ventricular longitudinal strain was deteriorated in both the milrinone and levosimendan groups; 33% and 39%, respectively. The difference was not significant. The corresponding deterioration in right ventricular longitudinal strain was 42% and 50% (non-significant difference). For both groups, biventricular longitudinal strain approached their preoperative values at hospital discharge. Preoperative N-terminal pro-brain natriuretic peptide could predict the left ventricular strain on postoperative day one (p=0.014). Conclusions : Levosimendan was comparable to milrinone for left and right ventricular inotropic support in pediatric cardiac surgery.