Preoperative levosimendan infusion in combined aortic valve and coronary bypass surgery.

ABSTRACT

BACKGROUND: Cardiopulmonary bypass may have detrimental effects on intestinal function and decrease the concentrations of the active, long-acting metabolites of levosimendan, an inodilator used to improve cardiac function. The aim of this study was to evaluate the haemodynamic effects of preoperative levosimendan in patients undergoing high-risk cardiac surgery. METHODS: Twenty-four patients were randomized to receive levosimendan (12 µg bolus followed by an infusion of 0.2 µg kg(-1) min(-1)) or a placebo 24 h before surgery. The inclusion criteria were left ventricular ejection fraction (LVEF) <50% or LV hypertrophy indicated by a wall thickness of >12 mm. Haemodynamics were recorded every hour for 24 h (pulmonary artery catheter) and daily until postoperative day 4 (whole-body impedance cardiography). Doppler echocardiography with tissue Doppler imaging was used to assess systolic and diastolic cardiac function. RESULTS: The cardiac index (CI) and stroke volume index (SI) were higher in the levosimendan group (LG) for the 4 day postoperative period (P<0.05); on the fourth postoperative day, the CI was 3.0 litre m(-2) min(-1) in the LG compared with 2.4 litre m(-2) min(-1) in the control group (CG) and the SI was 30 vs 25 ml m(-2), respectively. The LVEF measured at baseline and on the fourth postoperative morning decreased in the CG, but was maintained in the LG. CONCLUSIONS: Levosimendan improved haemodynamics compared with a placebo in patients undergoing high-risk cardiac surgery. The concentrations of levosimendan's metabolites were higher compared with earlier studies using perioperative dosing.