Haemodynamic effects of levosimendan in patients during weaning from cardiopulmonary bypass

Levosimendan (LS) is a calcium sensitiser indicated for the treatment of acute heart failure that possesses a novel dual mechanism of action. It increases both cardiac contractility and induces coronary and systemic vasodilation. In this study the haemodynamic effects of LS were assessed in nine patients (classified as 'high risk') undergoing combined aortic or mitral valve repair/replacement and multiple coronary artery bypass grafting surgery. Immediately after weaning from cardiopulmonary bypass LS, 24 μg/kg, was given intravenously over 10 min. Haemodynamic data were recorded for up to 60 min post-infusion using thermodilution, 2-D transoesophageal echocardiography and pressure/volume analysis using a Millar 12 pole-conductance catheter with an integrated pressure sensor.

The results (Table 1) show that the LS infusion increased cardiac index (CI), mainly through an increase in stroke index (SI) and a decrease in systemic vascular resistance (SVR). LS treatment improved left ventricular contractility (+dP/dt) and end-systolic elastance (Ees), without a significant change in the left ventricular isovolumic pressure decline time constant (Tau). LS increased coronary graft flow by 32% (P < 0.05). No arrhythmias occurred during the 60-min study period.

Table 1 Haemodynamic parameters (mean ± SD) before and after the administration of levosimendan

In conclusion, a 10-min intravenous infusion of LS significantly improved left ventricular function and contractility without impairing the rate of ventricular relaxation.