Department of Surgery, Division of Cardiac Surgery, University of Verona, Verona, Italy.
J Thorac Cardiovasc Surg. 2012 Jan;143(1):209-14. doi: 10.1016/j.jtcvs.2011.09.020. Epub 2011 Oct 19.
To investigate effects of epinephrine and levosimendan on cardiac function after rewarming from deep hypothermia.
Forty-five male Wistar rats (400-500 g) underwent cardiopulmonary bypass and were cooled to a core temperature of 13°C to 15°C within 30 minutes. After 15 minutes of deep hypothermic circulatory arrest, they were randomly assigned to treatment with levosimendan (12 μg/kg; infusion of 0.2 μg · kg(-1) · min(-1)) (n = 15) or epinephrine (0.1 μg/kg; infusion of 0.1 μg · kg(-1) · min(-1)) (n = 15) or saline as control (n = 10). The rewarming lasted 60 minutes. Systolic and diastolic function was evaluated at different preloads with a conductance catheter, including the slope of the end-systolic pressure-volume relation (ESPVR) and end-diastolic pressure-volume relationship (EDPVR), preload recruitable stroke work, first derivative of left ventricular pressure (+dP/dt), and its relation to end-diastolic volume, as well as the time constant of left ventricular relaxation (Tau) and maximal slope of the diastolic pressure decrement (-dP/dt). Plasma lactate levels were collected.
Stroke volume, ejection fraction and +dP/dt were significantly higher in the levosimendan-treated group than in the epinephrine group. The slope values of preload recruitable stroke work, ESPVR, and the relation of +dP/dt to end-diastolic volume were significantly higher, indicating a better contractility and increased systolic function. -dP/dt was significantly higher in the levosimendan group (3468 ± 320 vs 1103 ± 101 mm Hg/s; P < .01). Left ventricular stiffness expressed by EDPVR and relaxation (Tau) were significantly improved in levosimendan-treated group. Plasma lactated concentrations were lower in levosimendan group (2.03 ± 1.27 vs 4.64 ± 1.02; P < .05).
Levosimendan has better inotropic and lusitropic effects than epinephrine during rewarming from deep hypothermic circulatory arrest with cardiopulmonary bypass.
研究去甲肾上腺素和左西孟旦对深低温停循环复温后心功能的影响。
45 只雄性 Wistar 大鼠（400-500g）行心肺转流，在 30 分钟内降温至核心温度 13°C-15°C。深低温停循环 15 分钟后，随机给予左西孟旦（12μg/kg；输注 0.2μg·kg(-1)·min(-1))（n=15）、去甲肾上腺素（0.1μg/kg；输注 0.1μg·kg(-1)·min(-1))（n=15）或生理盐水（n=10）治疗。复温持续 60 分钟。使用心阻抗导管评估不同前负荷下的收缩和舒张功能，包括收缩末期压力-容积关系（ESPVR）和舒张末期压力-容积关系（EDPVR）斜率、前负荷可诱导的搏功、左心室压力的一阶导数（+dP/dt）及其与舒张末期容积的关系，以及左心室松弛时间常数（Tau）和舒张期压力下降的最大斜率（-dP/dt）。收集血浆乳酸水平。
左西孟旦组的每搏量、射血分数和+dP/dt 均显著高于去甲肾上腺素组。前负荷可诱导的搏功、ESPVR 斜率值和+dP/dt 与舒张末期容积的关系明显更高，提示收缩性更好，收缩功能增强。左西孟旦组-dP/dt 明显更高（3468±320 比 1103±101mmHg/s；P<0.01）。左西孟旦组左心室僵硬度（EDPVR 和舒张期（Tau））明显改善。左西孟旦组血浆乳酸浓度较低（2.03±1.27 比 4.64±1.02；P<0.05）。
在心肺转流深低温停循环复温期间，左西孟旦的正性肌力和变力作用优于去甲肾上腺素。
