St.Thomas NO.2停跳液与含血心肌停跳液对未成熟兔心肌的保护作用

比较观察St.ThomasNO .2停跳液与含血心肌停跳液对未成熟兔心肌的保护作用 ,以期为未成熟心肌保护的临床应用找到一种更有效的方法。选用生后 14～ 2 1天新西兰兔 12只 ,在改良的Langendorff模型上 ,对St.ThomasNO .2停跳液及含血心肌停跳液分别进行低温缺血再灌注离体心脏实验。观察缺血前后心功能变化 (左心室最大压力变化速率、左心室搏出功、左心室搏出功指数及心输出量等指标 )、心肌含水率及心肌酶学的变化。结果发现 ,离体心脏缺血再灌后 ,含血心肌停跳液组左心室最大压力变化速率、左心室搏出功、左心室搏出功指数和心输出量等心功能指标恢复明显好于St.ThomasNO .2停跳液组 (P <0 .0 5 ) ;含血心肌停跳液组心肌肌酸激酶及乳酸脱氢酶漏出率与St.ThomasNO .2停跳液组相比明显降低 (P <0 .0 5 ) ;但两组心肌含水率无明显差异。结果提示 ,初步证实含血心肌停跳液对未成熟心肌的心肌保护效果比St.ThomasNO .2停跳液效果好     

常温体外循环心脏缓慢空跳状态下心肌保护效果的实验研究

目的　评价常温体外循环心脏缓慢空跳术式对心肌保护效果的影响。方法　杂种犬 12只 ,随机分为停跳组和空跳组。两组均常规建立体外循环。停跳组阻断升主动脉 ,心脏灌注冷晶体停跳液 ;空跳组不阻断升主动脉 ,以一定的灌注压力和流量维持心脏空跳。分别于停跳 (开机 )前、停跳 (空跳 ) 90min、复跳 (撤机 ) 30min ,抽冠状窦血行有关生化检测、取右心室心肌行病理组织检查。结果　停跳组在刚复跳及复跳 30min其冠状窦血中丙二醛 (malondialdehyde ,MDA)及乳酸脱氢酶同工酶 (lacticaiddehydrogenase,LDH1)值均显著高于停跳前 (P <0 0 5 ) ,并显著高于空跳组撤机 30min时的MDA及LDH1值 (P <0 0 5 ) ;而空跳组在研究时段12 0min内其心脏冠状窦血MDA及LDH1值均无显著性差异(P >0 0 5 )。在心肌超微结构改变方面 :停跳组在停跳 90min及复跳 30min ,均出现较严重心肌损伤的改变 ,而空跳组同样时段仅出现轻度可逆性改变。结论　体外循环下空跳法在减少心肌损害 ,避免缺血再灌注损伤方面优于停跳法。     

冷挛缩对未成熟心肌功能、能量代谢与超微结构的影响

目的 :建立冷挛缩模型 ,探讨冷挛缩对未成熟心肌功能、能量代谢与超微结构的影响。方法 :在离体工作心模型基础上 ,30只新西兰幼兔 ( 3～ 4周 )随机分成三组 : 组 (对照组 ,n =10 ) , 组 (冷挛缩组 ,n =10 ) , 组 (冷挛缩 低钙心肌保护液组 ,n =10 )。离体缺血再灌注复苏 ,测试缺血前、后心功能 ,心输出量 ,左室收缩压 ,左室舒张末压 ,最大压力变化速率 ,缺血后冠状静脉窦流出液乳酸脱氢酶 ( L DH) ,肌酸激酶 ( CK) ,心肌组织水含量 ,三磷酸腺苷 ( ATP)、二磷酸腺苷、一磷酸腺苷含量 ,电镜观察缺血后心肌超微结构。结果 :离体心缺血再灌注复苏后 ,心功能恢复、电镜观察缺血后超微结构 、 组优于 组 , 、 组 ATP含量始终高于 组 ( P <0 .0 5 ) ,而 组 L DH、CK和心肌组织水含量高于 、 组 ( P <0 .0 5 )。结论 :冷挛缩对缺血后心功能恢复和能量代谢不利 ,低钙心肌保护液有利于减轻冷挛缩损伤     

褪黑激素对心肌缺血再灌注损伤的保护作用

目的 :探讨褪黑激素增补于停搏液中对缺血再灌注离体鼠心的保护作用。方法 :将 2 4只Wistar大鼠随机分为褪黑激素组 ,对照组。离体鼠心在改良的Langendorff Neely灌注模型上 30min预灌注 ,12 0min停搏 ,30min再灌注。缺血前及再灌注期间测定血流动力学指标 ,心肌酶 (CPK ,LDH)、心肌超氧化物歧化酶(SOD)、过氧化脂质 (LPO)含量。电镜观察心肌超微结构。结果 :再灌注后 ,褪黑激素组心功能、心肌超微结构的改善明显优于对照组 ;CPK ,LDH ,LPO含量显著低于对照组 (P <0 .0 1) ;SOD含量显著高于对照组 (P <0 .0 1)。结论 :褪黑激素增补于停搏液中可显著减轻心肌缺血再灌注损伤 ,具有良好的心肌保护作用     

血液停跳液与晶体停跳液对冠状动脉搭桥术患者术中心肌保护的比较

目的比较血液停跳液和晶体停跳液对冠心病(CAD)患者冠状动脉搭桥术中心肌保护的效果,探讨损伤心肌恢复的指标。方法将53例择期手术的CAD患者分为两组:血液停跳液组(B-CAD)和晶体停跳液组(C-CAD)。分别于术前1d,术后1、3、5、8d晨取静脉血,测定血清天冬氨酸转氨酶(AST)、磷酸肌酸激酶及同功酶M(BCK,CK-MB)、乳酸脱氢酶及同功酶(1LDH,LDH-1)。结果两组患者术前心肌酶的测定结果均在正常范围,术后1d两组的心肌酶释放达到高峰(P<0.05),术后3d均有不同程度的恢复,两组的CKMB已恢复到正常值,C-CAD组的AST与术前相比已无明显差别(P>0.05),但两组的其他心肌酶仍明显高于术前水平(P<0.05)。术后5d继续恢复,两组的CK也恢复到正常水平,但两组的LDH和LDH-1在术后5d和术后8d仍高于术前水平(P<0.05)。术后1d、3dB-CAD的LDH和LDH-1以及术后5dB-CAD的LDH均明显高于C-CAD的测定值(P<0.05),两组间其他心肌酶值在不同的时间差异无统计学意义。以术前心肌酶的值对术后心肌酶值进行校正后,两组间心肌酶的释放在术后各个测定点差异均无统计学意义。心肌酶的释放与主动脉阻断时间(CCT)和体外循环时间(ECCT)呈良好的正相关。两组患者的年龄、体重、CCT和ECCT差别无统计学意义(P>0.05)。结论从心肌酶的释放来判断,血液停跳液并不优于晶体停跳液对CAD的心肌保护效果。要判断心肌损伤的恢复,应以LDH和LDH-1的恢复为标准。     

温血停跳液持续灌注与冷晶体停跳液间断灌注对心肌保护作用的比较

本文从临床效果、心肌酶代谢及细胞超微结构的变化方面，比较温血停跳液持续灌注与冷晶体停跳液间断灌注对心肌的保护作用。结果为，常温组术后自动复跳率为９２．３％，低温组仅２３．１％；常温组心肌酶释放减少，术后心脏功能恢复较快；心肌超微结构观察显示常温组细胞线粒体损伤较轻，心肌破坏较少。表明常温体外循环行温血停跳液持续灌注，对心肌的保护作用较以往的低温体外循环用冷晶体停跳液间断灌注为佳。     

吡那地尔介导的超极化停搏液对未成熟兔心肌保护的研究

对20只幼兔随机分为吡那地尔介导的超极化停搏组（P组）和未加吡那地尔的去极化停搏组（S组）。通过改良的langendorff离体心脏灌流，观察两组心脏机械停搏时间、复跳时间、心肌收缩力、冠脉流量以及心肌中丙二醛（MDA）、乳酸脱氢酶（LDH）、肌酸磷酸激酶（CK）水平和心肌超微结构的变化。结果：P组心肌收缩力、冠脉流量恢复率均高于S组（P均〈0．05），心肌LDH、MDA、CK水平较低（P均〈0．05），心肌细胞超微结构较S组得到更好保护。认为吡那地尔介导的超极化停搏液对未成熟兔心肌的保护优于去极化停搏液。     

天麻素在铁诱导的大鼠离体心肌损伤中的保护作用

目的观察天麻素在铁诱导的大鼠离体心肌损伤中的保护作用。方法应用Langendorff离体心脏灌流系统,灌注Fe-HQ建立铁诱导的离体心肌损伤模型。SD大鼠随机分成4组:正常组、Fe-HQ组、天麻素(0.1、0.025 mmol/L)组。观察天麻素对心率(HR)、左室收缩压(LVSP)、dp/dt max、冠脉流量(CF)的影响;测定冠脉流出液中的乳酸脱氢酶(LDH)及肌酸激酶(CK)的含量和心肌中丙二醛(MDA)的浓度;观察心肌组织的超微结构。结果天麻素能抑制铁诱导的心肌的HR、LVSP、dp/dt max、CF的下降;降低冠脉流出液中LDH和CK的含量及心肌中MDA的浓度。结论天麻素可改善铁诱导的心肌收缩功能和脂质过氧化,对铁诱导的大鼠离体心肌损伤有显著的保护作用。     

晶体停跳液和含血停跳液的临床应用研究

目的：观察晶体停跳液和含血停跳液对心肌的保护作用。方法：２０例择期性心脏瓣膜替换术患者分别用晶体停跳液（１０例）和含血停跳液（１０例）灌注的结果进行分析。结果：两组在直视手术中心脏停跳良好。围术期血液动力学指标，平均动脉压、中心静脉压、心率无明显差异。心肌摄氧率大致相同。但晶体停跳液组的冠状动脉乳酸摄取率明显低于含血停跳液组，而含血停跳液组的血浆肌酸激酶及其同功酶的水平明显低于晶体停跳液组。电子显微镜观察可见晶体停跳液组右心房心肌的超微结构（线粒体、肌丝）严重损坏，而含血停跳液组对其有明显保护效果。含血停跳液组自动复跳率（６０．５％）明显高于晶体停跳液组（４４．９％）。结论：含血停跳液有很多优点，如临床安全性、心肌酶释放减少、超微结构损伤轻等。     

一体化综合性心肌保护对婴幼儿心肌超微结构的保护

目的：观察一体化综合性心肌保护方法对婴幼儿心肌超微结构的影响以评价其心肌保护效果。方法：30例复杂先天性心脏病患儿随机分成一体化综合性心肌保护组（综合组，含温血停搏液诱导停搏，冷血停搏液间歇灌注和终末温血灌注液复苏）、冷血停搏液间断灌注组（冷血组），及冷晶体停搏液间断灌注组（冷晶组），各10例。于心脏停跳即刻、缝合右心房切口前分别取小块右心房肌肉作光镜及电镜观察，并对线粒体、细胞核、肌纤维进行定量评估。结果：三组心肌均存在不同程度的损伤，冷晶组最重，综合组最轻。心肌超微结构评分在三组之间两两比较较有统计学意义（P〈0．01或P〈0．05）。结论：一体化综合性心肌保护作用优于冷血停搏液和冷晶体停搏液。     

Stroke rate of off-pump coronary artery bypass; aortocoronary bypass versus in-situ bypass

Off-pump coronary artery bypass (OPCAB) using in-situ grafts does not require aortic manipulation, and it is theoretically free from the risk of stroke. Because of the limited availability of in-situ grafts, aortocoronary bypass has been conducted in addition to in-situ grafting. In this paper, the authors prospectively investigated whether or not on aortocoronary bypass increases the incidence of stroke after off-pump bypass. Perioperative data were collected prospectively from patients who underwent isolated off-pump bypass at their hospital group between March 1997 and February 2002. The patients were divided into 2 groups; group AC (patients with at least 1 aortocoronary bypass, n = 280) and group IS (patients with all in-situ grafts, n = 234). Patients with 3-vessel disease more frequently underwent aortocoronary bypass and patients with a history of stroke, calcified ascending aorta, or renal failure more often underwent in-situ graft. The number of distal anastomoses was greater in group AC (3.5 +/- 1.0) than in group IS (2.7 +/- 1.1), p < 0.0001. Patient recovery and complication rates were similar, including the occurrence of postoperative stroke: 3.0% (7/234) in group IS vs 0.7% (2/280) in group AC, p = 0.051, NS. The graft patency and remote results were not significantly different between the 2 groups. Side clamping of the aorta used in off-pump aortocoronary bypass does not increase the risk of postoperative strokes compared to in-situ bypass. Postoperative stroke after OPCAB may depend on the patient's preoperative comorbidities.     

Concomitant aortoaxillary bypass and coronary artery bypass grafting

The optimal revascularization strategy for patients with subclavian and coronary artery disease has not been established. This study assessed the mid-term clinical outcome of concomitant aortoaxillary bypass and coronary artery bypass grafting in 5 patients. A ring-reinforced polytetrafluoroethylene graft was attached to the ascending aorta and led to the proximal segment of the axillary artery via the pleural cavity. Patients were followed up for 2-10 years (mean, 5.4 +/- 3.4 years). Postoperative aortography and angiography demonstrated patent aortoaxillary and coronary bypass grafts in the short-term follow-up of all patients. Two patients with Takayasu aortitis needed re-operations for recurrent angina and annuloaortic dilatation. Another patient required removal of the aortoaxillary bypass graft because of infection, and subsequently underwent a left femoroaxillary bypass one year after the original procedure. Subclavian steal phenomenon did not occur. Aortoaxillary bypass with coronary artery bypass may be an effective option for patients with co-existing subclavian and coronary artery disease.     

Coronary endarterectomy and bypass grafting without cardiopulmonary bypass

We prospectively analyzed patients who underwent simultaneous off-pump coronary artery bypass grafting and endarterectomy between March 1, 1997 and February 28, 2002. The incidence of perioperative myocardial infarction, need for inotropic support, morbidity, long-time functional class, and mortality were evaluated.Nine endarterectomies were performed in eight patients, more frequently in the right coronary artery. Dopamine was used in four patients. One perioperative myocardial infarction (12.5%) occurred. No deaths occurred and all patients are now functional class I. Tests for ischemia have been negative in all patients.Coronary endarterectomy is an alternative procedure that has little morbidity and enables complete myocardial revascularization without cardiopulmonary bypass.     

Cardiopulmonary bypass

There has been a recent renewed interest in certain aspects of cardiopulmonary bypass employing extracorporeal circulation. Several areas have received special attention. Among these is the institution of extracorporeal circulation using a percutaneous technique for circulatory assistance during high-risk percutaneous transluminal coronary angioplasty. A national registry has been established to review and monitor results using this percutaneous technique. Several recent developments in the delivery of cardioplegia during ischemic arrest have stimulated investigative efforts. In particular, the delivery of cardioplegia in a retrograde manner through the coronary sinus has proved an effective and useful adjunct to myocardial protection during cardiopulmonary bypass with extracorporeal circulation. A newer investigative technique employing only warm cardioplegia delivered primarily through the retrograde coronary sinus route seems to offer some promise in providing optimal myocardial protection while minimizing hemorrhagic complications and other cold-induced myocardial injury. Because of concerns regarding blood transfusion-related communicable disease (eg, acquired immune deficiency syndrome and non-A, non-B hepatitis), there has been increasing research effort into postoperative hemorrhage related to cardiopulmonary bypass with extracorporeal circulation. Specifically, various drugs that may serve as hemostatic adjuncts have been investigated extensively. These drugs include aprotinin and desmopressin acetate. Likewise, several studies have evaluated other drugs (mainly aspirin) that have a negative influence on postoperative hemostasis. Additionally, there has been continued research interest in the activation of the inflammatory system during cardiopulmonary bypass.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gastric bypass

The success of gastric bypass probably depends on factors other than merely the restrictive size of the gastric pouch and outlet. Postoperative dumping and a mild degree of malabsorption derived from the redirection of intestinal contents contribute to long-term success. Thus, gastric bypass combines some elements of both malabsorptive and gastric restrictive procedures.