Levosimendan in Aortic Valve Surgery: Cardiac Performance and Recovery

Objective: The aim of the present study was to test the hypothesis that levosimendan has beneficial effects on cardiac performance and that the need for other vasoactive medications during and after cardiac surgery would be reduced by levosimendan in patients with severe aortic stenosis (AS) and left ventricular (LV) hypertrophy.

Design: A prospective, randomized, double-blind, placebo-controlled clinical study.

Setting: A university hospital.

Participants: Twenty-four patients scheduled for aortic valve surgery with or without coronary artery bypass graft surgery were enrolled in the study.

Interventions: Twelve patients received a 24-hour levosimendan infusion (0.2 μg/kg/min) beginning after the induction of anesthesia, and 12 patients received a placebo infusion.

Measurements and Main Results: Left ventricular ejection fraction, measured before study drug infusion, was lower in the treatment group than in the control group (42% v 54%, p = 0.015). After sternum closure, the ejection fraction dropped in the control group but was maintained at the same level in the treatment group (45% v 48%, not significant). Mixed venous and central venous saturations were significantly lower in the treatment group than in the control group at the baseline, but after the beginning of the study drug infusion, the groups were similar throughout the rest of the follow-up period. The treatment group required more norepinephrine during the operation and less nitroprusside postoperatively.

Conclusions: Low output is a result of myocardial stunning and is common after cardiopulmonary bypass. According to the present results, levosimendan may be useful in patients with severe AS and LV hypertrophy because it may prevent LV function from dropping to a critically low level postoperatively. Levosimendan causes vasodilation and thereby decreases mean arterial pressure, but this can be controlled with the use of norepinephrine.

Key Words: levosimendan, calcium sensitizers, aortic valve surgery, aortic stenosis