Malliotakis Polychronis, Xenikakis Theophilos, Linardakis Manolis, Hassoulas John
Department of Cardiothoracic Surgery, Heraklion University Hospital, P.O. Box 1352, 71110 Heraklion, Crete, Greece.
Hellenic J Cardiol. 2007 Mar-Apr;48(2):80-8.
Levosimendan is a new inotropic vasodilator for the treatment of decompensated heart failure. Compared to other inotropic agents, it has been shown to improve myocardial contractility without increasing oxygen requirements. However, experience with levosimendan in patients with low cardiac output after cardiopulmonary bypass is limited. In this case series we present the short-term haemodynamic effects of levosimendan added to dobutamine for the management of low cardiac output syndrome after cardiac surgery.
Twelve patients with low cardiac output during the first 6 hours after completion of cardiopulmonary bypass, who were already receiving dobutamine at a mean dose of 6.7 microg/kg/min, were treated with levosimendan at a loading dose of 6 microg/kg, followed by a 24-hour infusion of 0.2 microg/kg/min. During a 24-hour observation period the following haemodynamic parameters were measured: arterial, central venous, pulmonary arterial and pulmonary capillary wedge pressure, heart rate, cardiac index, stroke volume, systemic and pulmonary vascular resistance, as well as mixed venous oxygen saturation, oxygen delivery and oxygen extraction ratio.
Levosimendan significantly improved cardiac index (from 2.1 +/- 0.1 L/min/m2 at baseline to 3.2 +/- 0.3 L/min/m2 at 24 hrs, p < 0.001) as well as mixed venous oxygen saturation, oxygen delivery and oxygen extraction ratio (p < 0.001) and caused a significant reduction in systemic and pulmonary vascular resistance (p < 0.001). At the same time, a significant decrease in central venous, pulmonary arterial and pulmonary capillary wedge pressure was noted (p < 0.001). These beneficial haemodynamic effects resulted in significantly decreased catecholamine requirements.
In this group of cardiac surgical patients with postoperative myocardial dysfunction resistant to dobutamine, levosimendan added to dobutamine was effective in reversing low cardiac output syndrome.
左西孟旦是一种新型的强心血管扩张剂，用于治疗失代偿性心力衰竭。与其他强心剂相比，它已被证明可改善心肌收缩力而不增加氧需求。然而，体外循环后心输出量低的患者使用左西孟旦的经验有限。在本病例系列中，我们展示了在多巴酚丁胺基础上加用左西孟旦对心脏手术后低心输出量综合征的短期血流动力学影响。
12例在体外循环结束后最初6小时内心输出量低的患者，他们已经在接受平均剂量为6.7微克/千克/分钟的多巴酚丁胺治疗，接受了负荷剂量为6微克/千克的左西孟旦治疗，随后以0.2微克/千克/分钟的速度进行24小时输注。在24小时观察期内，测量以下血流动力学参数：动脉压、中心静脉压、肺动脉压和肺毛细血管楔压、心率、心脏指数、每搏量、体循环和肺循环血管阻力，以及混合静脉血氧饱和度、氧输送和氧摄取率。
左西孟旦显著改善了心脏指数（从基线时的2.1±0.1升/分钟/平方米提高到24小时时的3.2±0.3升/分钟/平方米，p<0.001）以及混合静脉血氧饱和度、氧输送和氧摄取率（p<0.001），并导致体循环和肺循环血管阻力显著降低（p<0.001）。同时，中心静脉压、肺动脉压和肺毛细血管楔压显著下降（p<0.001）。这些有益的血流动力学效应导致儿茶酚胺需求量显著减少。
在这组对多巴酚丁胺耐药的心脏手术术后心肌功能障碍患者中，在多巴酚丁胺基础上加用左西孟旦可有效逆转低心输出量综合征。
