Comparison of Levosimendan versus Dobutamine in Patients with Moderate to Severe Left Ventricular Dysfunction Undergoing Off-pump Coronary Artery Bypass Grafting: A Randomized Prospective Study

CONTEXT: Recent upsurge in referral of patients with compromised left ventricular (LV) function for cardiac surgery has led to an increasing use inotropes to achieve improvement of tissue perfusion in the perioperative period. AIMS AND OBJECTIVES: To compare the hemodynamic effects and immediate postoperative outcomes with levosimendan and dobutamine in patients with moderate to severe LV dysfunction undergoing off-pump coronary artery bypass grafting (OPCAB). SETTINGS AND DESIGN: University teaching hospital, randomized control study. MATERIALS AND METHODS: Eighty patients were randomly divided into two groups of 40 each. Group I received levosimendan at 0.1 μg/kg/min and Group II received dobutamine at 5 μg/kg/min. Hemodynamic data were noted at 30 min, during obtuse marginal grafting, 1, 6, 12, and 24 h after surgery. Heart rate (HR), mean arterial pressure (MAP), pulmonary capillary wedge pressure (PCWP), cardiac index (CI), systemic vascular resistance index (SVRI) and pulmonary vascular resistance index (PVRI), left ventricular stroke work index (LVSWI) and right ventricular stroke work index (RVSWI), mixed venous oximetry (SvO(2)), and lactate were measured. STATISTICAL ANALYSIS USED: Chi-square and Student's t-test. RESULTS: The HR, MAP, PCWP, SVRI, and PVRI were lower in Group I when compared to Group II. Group I patients showed a statistically significant increase in LVSWI, RVSWI, and CI, when compared to Group II. Comparatively, Group I patients maintained higher SvO(2) and lower lactate levels. Duration of ventilation, Intensive Care Unit (ICU), and hospital stay were lower in Group I. CONCLUSIONS: Levosimendan was associated with statistically significant increase in indices of contractility (CI, LVSWI, and RVSWI) and decrease in PCWP during and after OPCAB. Levosimendan group had lower incidence of atrial fibrillation, shorter length of ICU, and hospital stay.