Comparitive study of efficacy and haemodynamic safety of levosemendan with dobutamine in patients with severely reduced left ventricular funtion undergoing cardiac surgery
Levosimendan, a novel calcium sensitizer, improves myocardial contractility without causing an increase in myocardial oxygen demand as compared to other inotropes.
Aims and Objectives
We aimed to compare the hemodynamic effects of levosimendan and dobutamine in patients with EF < 30% undergoing coronary artery bypass grafting (CABG) electively on cardiopulmonary bypass (CPB).
Materials and Methods
60 patients were divided into 2 groups of 30 each. Group-L patients received levosimendan 6 μg/kg loading for 10 mins followed by continuous infusion of 0.2 μg/kg/min upto 24 hrs and Group-D patients received dobutamine 5 μg/kg/min while weaning off CPB without a loading dose and continued upto 24hrs. Additional inotrope and/or vasoconstrictor were started based on hemodynamic parameters. Hemodynamic data were collected at baseline, 30 minutes after CPB, thereafter at 6, 12, 24, and 36 hours post-CPB. Mean arterial pressure (MAP), central venous pressure (CVP), Pulmonary arterial pressure (PAP), pulmonary capillary wedge pressure (PCWP), heart rate (HR), stroke volume (SV), CO (cardiac output), cardiac index (CI), systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), and lactate levels were measured.
Group-L showed increased requirement of inotropes and vasoconstrictors. The MAP, CVP, PAP were reduced more in Group-L. The CI, CO, SV were higher in Group-L when compared to Group-D, patients showed a statistically significant increase in CI, CO, SV even after 12 hrs of discontinuation of levosimendan. Compared with dobutamine group, SVRI and PVRI was significantly lower at 6, 12, 18, and 24 hour post CPB in levosimendan group, requiring additional inotropes. The HR was higher in Group-D. Lactate levels, intensive care unit stay, and duration of ventilation were similar in both groups.
Levosimendan loading dose 6 μg/kg for 10 mins followed by 0.2 μg/kg/min compared to dobutamine 5 μg/kg/min caused rapid dose-dependent improvement in hemodynamic function, showed more vasodilation and lesser inotropy in patients undergoing CABG. The requirement of another inotrope or vasopressor was frequent in levosimendan group.
Hemodynamics variables, Levosimendan, dobutamine, CABG.