Crooke G A, Harris L J, Grossi E A, Baumann F G, Esposito R, Spencer F C, Colvin S B, Galloway A C
Department of Surgery, New York University Medical Center, NY 10016.
J Thorac Cardiovasc Surg. 1993 Sep;106(3):497-501.
The purpose of this study was to determine the effects of the addition of amino acids to blood cardioplegic solution and the value of terminal cardioplegia enhancement techniques in routine myocardial protection. Forty-five open-chest adult dogs were instrumented with sonomicrometry crystals to measure left ventricular long axis, midequatorial short axis, and wall thickness. The aorta was clamped for 120 minutes of cardiopulmonary bypass. Animals were randomly separated into four myocardial protection groups: (1) blood cardioplegic solution with amino acids and no terminal cardioplegia (n = 12); (2) blood cardioplegic solution with amino acids and warm amino acid terminal cardioplegia (n = 11); (3) blood cardioplegic solution with amino acids and cold amino acid terminal cardioplegia (n = 12); and (4) blood cardioplegic solution plus cold terminal cardioplegia (no amino acids, n = 10). Data for preload recruitable stroke work were obtained by inflow occlusion before bypass (baseline) and at 30 and 60 minutes after reperfusion and analyzed for changes in x-intercept and slope. A significant rightward shift in x-intercept did not occur in any group. When cardiac function was expressed as a percentage of baseline preload recruitable stroke work slope, improved functional recovery was seen at both 30 and 60 minutes in groups 2 (88.6% and 91.8%), 3 (85.8% and 86.9%), and 4 (88.6% and 92.6%) compared with group 1 (77.3% and 79.2%, p < 0.05). No significant difference was found in the degree of functional recovery among groups 2, 3, and 4. These results suggest that for myocardial protection of 2 hours in nonischemic hearts, a terminal dose of blood cardioplegic solution before unclamping is beneficial, but this positive effect is independent of amino acid supplementation and temperature.
本研究的目的是确定在血液停搏液中添加氨基酸的效果以及终末停搏增强技术在常规心肌保护中的价值。45只成年开胸犬植入超声心动图晶体以测量左心室长轴、赤道中短轴和壁厚。在体外循环期间主动脉夹闭120分钟。动物被随机分为四个心肌保护组：（1）含氨基酸的血液停搏液且无终末停搏（n = 12）；（2）含氨基酸的血液停搏液和温氨基酸终末停搏（n = 11）；（3）含氨基酸的血液停搏液和冷氨基酸终末停搏（n = 12）；（4）血液停搏液加冷终末停搏（无氨基酸，n = 10）。通过在体外循环前（基线）和再灌注后30分钟及60分钟时进行流入道阻断来获取前负荷可募集搏功数据，并分析x轴截距和斜率的变化。任何组均未出现x轴截距显著右移。当心脏功能以基线前负荷可募集搏功斜率的百分比表示时，与第1组（77.3%和79.2%，p < 0.05）相比，第2组（88.6%和91.8%）、第3组（85.8%和86.9%）和第4组（88.6%和92.6%）在30分钟和60分钟时均观察到功能恢复改善。第2、3和4组之间的功能恢复程度未发现显著差异。这些结果表明，对于非缺血心脏2小时的心肌保护，在松开主动脉夹之前给予终末剂量的血液停搏液是有益的，但这种积极作用与氨基酸补充和温度无关。
