心肌肌钙蛋白Ⅰ对体外循环期心肌损伤的判定价值

目的 探讨心肌肌钙蛋白Ｉ（ｃＴｎＩ）对体外循环期心肌损伤的判定价值。方法 ２０例心内直视手术病人随机分为两组,冷晶体停跳组（组Ｉ）,冷氧合血停跳组（组Ⅱ）,每组１０例,分别于围术期多外时点采取中心静脉血,测定血清ｃＴｎＩ、ＣＫ及ＣＫ－ＭＢ的水平,并观察缺血前后心肌超微结构变化。结果 术前两组的ｃＴｎＩ、ＣＫ及ＣＫ－ＭＢ水平均在正常范围,开放主动脉后１ｈ至术后２４ｈ达峰值,其后缓慢下降。术后２４ｈ     

冠状动脉旁路移植术围术期心肌肌钙蛋白Ⅰ动态变化

目的 观察心肌肌钙蛋白Ⅰ和ＣＫ－ＭＢ在冠状动脉旁路移植术（ＣＡＢＧ）围术期变化，以判断心肌损伤状况。方法 １９例ＣＡＢＧ病人，其中３例同时行左室室壁瘤切除。 平均体外循环时间１２１ｍｉｎ，阻断升主动脉５６ｍｍ，灌注冷血停跳液保护心肌，平均每例搭桥３．２支，围术期２０个时间点取静脉血标本，留血浆测ｃＴｎＩ和ＣＫ－ＭＢ。术主术后第７ｄ作标准１２导联心电图（ＥＣＧ）。结果 ｃＴｎＩ术前５例升主同者，停机     

西洋参二醇组皂甙对鼠心异位移植后心肌缺血再灌注？…

目的：了解西洋参二醇组皂甙（ＰＱＳ）作为心脏停搏液垢添加剂对鼠心异位移植后心肌缺血再灌注损伤的保护作用。方法：以鼠心腹部异位移植模型为研究手段,以心肌细胞钙主受体鼠血清中ＣＫ,ＣＫ－ＭＢ活力对观察指标,以Ｓｔ．ＴｈｏｍａｓⅡ号心脏停搏液为对照组,结果ＰＱＳ可降低移植心脏心肌细胞内钙含量,降低受体鼠血清中ＣＫ,ＣＫ－ＭＢ活力,结论：ＰＱＳ抗缺血再灌注损伤的机理为钙拮抗剂样作用。     

纳洛酮对缺血再灌注心肌c-fos基因表达的影响

目的：研究纳洛酮对心肌缺血再灌注损伤的影响,从分子水平探讨心肌缺血再灌注损伤的保护机制。方法：３０只大白兔分为三组：（１）对照组;（２）心肌缺血３０分钟再灌３０分钟组;（３）静注纳洛酮１０分钟后缺血３０分钟再灌３０分钟组。提取心肌总ＰＮＡ与经同位素标记的ｃ－ｆｏｓ ｃＤＮＡ探针进行分子杂交并自显影,测定ｃ－ｆｏｓ基因ｍＲ－ＮＡ水平。结果：纳洛酮能显著抑制心肌缺血再灌注时ｃ－ｆｏｓ基因的表达。结论：     

心内直视手术中去白细胞血灌注液对心肌的保护作用

目的 评价心内直视手术期间使用滤除白细胞的血液灌注液对心肌的保护效果。方法 ３０例择期行心脏瓣膜替换术的患者，ＡＳＡⅡ～Ⅳ级，均采用芬太尼－安氟醚复合麻醉，以４℃高钾晶体液灌注停跳，据第二次灌注液成份不同随机分为３组，每组１０例；晶体 组（ＣＳ）、全血组（ＷＢ）和去白细胞血（ＬＤ）组，于肝素化前，ＣＰＢ开始５ｍｉｎ，主动脉开放前５ｍｉｎ，开放后３０ｍｉｎ、１ｈ、２ｈ、２４ｈ采取外周动脉血测定ＣＫ－ＭＢ、ＩＬ－８、ＴＮＦα浓度，于主动脉阻断前、开放前、开放后１５ｍｉｎ取右心房心肌标本，测定心肌含水量和心肌组织Ｃａ＾２＋含量和心肌组织Ｃａ＾２＋含量，观察心肌组织超微结构改变，对心肌线粒体变化进行半定量评价。结果 开放主动脉后，每组ＣＫ－ＭＢ、ＩＬ－８水平较开放前明显升高，开放后２ｈ升高更明显（Ｐ〈０．０５），但ＬＤ     

血清心型肌酸激酶对判断电损伤后心脏损害的临床价值

目的探讨电损伤后心脏损害的发病情况及判断电损伤后心脏损害的血清酶学指标。方法研究了３２例电接触性损伤患者的心电图、血清肌酸激酶（ＣＫ）和心型肌酸激酶（ＣＫＭＢ）活性。结果１７例患者有心电图异常（Ａ组）,１５例患者心电图基本正常（Ｂ组）。将测定的血清ＣＫＭＢ减１１％总ＣＫ的差定义为ＣＫＭＢ差值。Ａ组ＣＫ、ＣＫＭＢ、ＣＫＭＢ／ＣＫ比率和ＣＫＭＢ差值明显高于Ｂ组（全部：Ｐ＜００５）。Ａ组８８％的患者ＣＫＭＢ差值大于２５Ｕ／Ｌ,Ｂ组为６７％（Ｐ＜００１）。结论（１）心脏损害是电损伤的常见并发症,高压电更易于导致心脏损害;（２）血清ＣＫＭＢ,特别是ＣＫＭＢ差值可用于评价电损伤患者的心脏损害。     

西洋参二醇组皂甙对鼠心异位移植后心肌缺血再灌注损伤的保护作用

目的：了解西洋参二醇组皂甙（ＰＱＳ）作为心脏停搏液的添加剂对鼠心异位移植后心肌缺血再灌注损伤的保护作用。方法：以鼠心腹部异位移植模型为研究手段,以心肌细胞内钙含量及受体鼠血清中ＣＫ、ＣＫＭＢ活力为观察指标,以Ｓｔ．ＴｈｏｍａｓⅡ号心脏停搏液为对照组。结果：ＰＱＳ可降低移植心脏心肌细胞内钙含量,降低受体鼠血清中ＣＫ、ＣＫＭＢ活力。结论：ＰＱＳ抗缺血再灌注损伤的机理为钙拮抗剂样作用。     

地氟醚预处理对缺血／再灌注心肌的保护作用

目的 探讨地氟醚预处理抗心肌缺血／再灌注损伤作用及其可能机制,方法 ２０例心肌瓣膜置换术病人随机分为地氟醚观察组与芬太尼对照组,观察血浆过氧化脂质（ＬＰＯ）水平,红细胞超氧化物歧化酶（ＳＯＤ）活化,心脏指数（ＣＩ）,每搏指数（ＳＩ）,肌酸激酶同工酶（ＣＫ－ＭＢ）心肌细胞形态变化及开放主动脉后心脏复跳情况。结果 观察组再灌注后血浆ＬＰＯ与ＣＫ－ＭＢ浓度显著低于对照组,红细胞ＳＯＤ活性相对大于对照组,     

冠状动脉旁路移植手术围术期血清肌钙蛋白T水平的变化

目的 探讨肌钙旧白Ｔ作为心肌损伤生化樗物的价值。方法 连续选择冠状动脉旁路移植手术（ＣＡＢＧ）患者２２例，分别于麻醉前、体外循环（ＣＰＢ）前、ＣＰＢ结束后即刻和ＣＰＢ后２４小时，抽取静脉血４ｍｌ，用于肌酸激酶（ＣＫ）、肌酸激酶－ＭＢ（ＣＫ－ＭＢ）和心肌肌钙蛋白Ｔ（ｃＴｎＴ）的测定。结果 ＣＰＢ前ＣＫ、ＣＫ－ＭＢ和ｃＴｎＴ的中位数皆在正常范围内，ＣＰＢ后即刻和２４均显著性增高，ＣＫ以术后２４小时最为     

三磷酸腺苷-氯化镁对未成熟兔心肌缺血再灌注的保护作用

目的探讨未成熟心肌缺血再灌注损伤及三磷酸腺苷－氯化镁（ＡＴＰ－ＭｇＣｌ２）的保护作用。方法采用３～４周龄兔心建成离体左心做功模型，实验动物分为低温组：局部单纯低温组（１０～１５℃）；Ｔｈｏｍａｓ组：低温加Ｔｈｏｍａｓ液灌注组；ＡＴＰ－ＭｇＣｌ２组：低温加ＡＴＰ－ＭｇＣｌ２心停搏液灌注等３组，各组１２只，均全心停循环９０分钟，复灌流６０分钟。记录其心功能恢复率及病理生理的改变。结果ＡＴＰ－ＭｇＣｌ２组与低温组和Ｔｈｏｍａｓ组比较，心功能和心肌游离核苷酸含量恢复较好，冠状静脉流量高，心肌超微结构改变轻，而其磷酸肌酸激酶，心肌含水量及心肌线粒体丙二醛含量较低。结论ＡＴＰ－ＭｇＣｌ２作为心停搏液添加剂，对未成熟心肌缺血再灌注损伤有较好的保护作用     

Continuous retrograde warm blood reperfusion reduces cardiac troponin I release after heart transplantation: a prospective randomized study

Abstract During heart surgery, cardiac troponin I (cTn‐I) measurement provides a tool to evaluate different cardioprotective techniques. To investigate myocardial protection during heart transplantation (HTx), cTn‐I and creatine kinase (CK)‐MB release was measured in 42 patients randomized to receving either continuous retrograde warm blood reperfusion or no reperfusion after cold cardioplegia. A significant linear correlation was found between donor heart ischemic time and peaks and the area under the curve of cTn‐I and CK‐MB release. In patients with an ischemic time longer than 90 min, cTn‐I release was significantly lower in those receiving continuous retrograde warm cardioplegia than in controls. No significant difference was observed for CK‐MB, tCK, and myoglobin. Our data suggest that the measurement of postoperative cTn‐I release may provide a method to evaluate ischemic cardiac damage after HTx. When the ischemic time is longer than 90 min, warm retrograde blood cardioplegia provides better myocardial protection than no reperfusion.     

Comparison of cardiac troponin I and creatine kinase ratios in the detection of myocardial injury after aortic surgery

BACKGROUND: Perioperative myocardial infarction may not be diagnosed correctly because World Health Organization criteria are often not met and creatinine kinase myocardial fraction (creatinine kinase/creatinine kinase MB isoenzyme; CK/CK-MB) ratios can be difficult to interpret. Cardiac troponin (cTn) I and cTnT are the most sensitive and specific markers of myocardial cell necrosis currently available but are not widely used in surgical practice. The aim was to compare cTnI and CK/CK-MB ratios in the detection of myocardial injury following aortic surgery. METHODS: This was a prospective study of 59 patients undergoing elective (n = 28) or ruptured (n = 24) abdominal aortic aneurysm repair or elective aortofemoral bypass (n = 7). cTnI level was measured before operation and at 6, 24 and 48 h after surgery. The CK/CK-MB ratio was measured where cTnI was detectable. RESULTS: Some 14 of 24 emergency and ten of 35 elective patients had detectable cTnI (greater than 0.5 ng/ml) at one or more time-points. The CK/CK-MB ratio was greater than 5 per cent in only four of 24 patients having an emergency operation and in none of the elective patients with detectable cTnI. CONCLUSION: Over half of patients undergoing emergency operation and more than a quarter of those having elective aortic surgery suffered myocardial necrosis as determined by detectable cTnI levels. This was accompanied by a raised CK/CK-MB ratio in less than one-fifth of patients.     

右美托咪定预处理对心脏瓣膜置换术患者心肌肌钙蛋白Ⅰ和心肌酶学的影响

【摘要】〓目的〓观察右美托咪定预处理对脏瓣膜置换术患者心肌肌钙蛋白Ⅰ和心肌酶学的影响,探讨其对缺血再灌注损伤心肌的保护作用。方法〓拟择期行瓣膜置换术患者50例随机分为右美托咪定组(D组,n=25)和对照组(C组,n=25)。D组在麻醉诱导前经15 min静脉泵注右美托咪定0.5 μg/kg,随后以0.5 μg·kg^-1·h^-1速率泵注至阻断主动脉。C组泵注等容量生理盐水。所有患者手术前(T₀),主动脉阻断30 min(T₁)、主动脉开放1 h(T₂),术毕(T₃)和术后24小时(T₄)抽血测定磷酸肌酸激酶(CK)、磷酸肌酸激酶同工酶(CK-MB)的活性及心肌肌钙蛋白I(cTnI)的浓度。观察自动复跳率、心律失常发生率、左室射血分数(LVEF)以及血管活性药物使用情况。结果〓与C组相比,D组的cTnI浓度、CK和CK-MB的活性、多巴胺和肾上腺素用量低于C组;两组自动复跳率和心律失常发生率无统计学差异;D组术后LVEF值高于C组。结论〓右美托咪定预处理可减轻瓣膜置换患者的心肌损伤。     

Perioperative myocardial injury in patients undergoing aortic valve replacement

In cases of myocardial hypertrophy myocardial protection may be insufficient. In order to determine the factors responsible for myocardial injury we assessed myocardial injury in 54 patients undergoing isolated aortic valve replacement. In all cases hypothermic cardioplegic arrest was induced. At 13 different times we measured the serum level of creatine-kinase (CK), myocardial bound creatine-kinase (CKmb), lactic dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (alpha-HBDH), glutamic oxaloacetic transferase (GOT) and myoglobin. The mean duration of ischemia was 52.6 +/- 16.2 minutes and the mean time of extracorporeal circulation was 85.85 +/- 20.25 minutes. By performance of a multiple regression analysis a significant correlation between ischemia and LDH and alpha-HBDH was found; CK, GOT, LDH and alpha-HBDH correlated with duration of extracorporeal circulation. In none of the patients was a low cardiac output syndrome observed. From our results we conclude that in our study myocardial protection was sufficient and therefore the detrimental effects of extracorporeal circulation were the determining factors of enzyme release.     

No release of cardiac troponin I during major orthopedic surgery after acute normovolemic hemodilution

Background : Normovolemic hemodilution is a well-accepted method for intraoperative blood salvage. However, some controversy exists concerning the possible risk of myocardial fiber injury as a consequence of the reduced oxygen content. Laboratory diagnosis of perioperative myocardial fiber injury is difficult, since biochemical markers are elevated postoperatively due to the surgical trauma. Cardiac troponin I (cTnI) is a new, highly sensitive and specific cardiac marker for the detection of myocardial injury. The aim of our study was to investigate whether normovolemic hemodilution in patients with major orthopedic surgery (13 hemodiluted patients, 15 controls) induces a release of cTnI.
Methods : cTnI as a highly specific and sensitive cardiac parameter, as well as total creatine kinase (CK), creatine kinase isoenzyme MB mass (CKMB mass) and myoglobin were measured after induction of anesthesia, after normovolemic hemodilution, prior to retransfusion of blood components, 3 h after surgery, and on the first and third postoperative days. Results: Prior to retransfusion of blood components the hematocrit was decreased to 25.4±1.2% (mean±SEM; range: 18%–34%) in the control group and to 20.2±0.8% (mean±SEM; range: 17%-24%) in the hemodilution group. Total CK, CKMB mass as well as myoglobin concentration increased significantly in both groups, reaching their maxima within the first day of surgery. In contrast, cTnI was below the detection limit of the assay (<0.5 μg/L) at any time.
Conclusions : We suggest that pre- and intraoperative hemodilution to a hematocrit of approximately 20% by maintaining normovolemia does not induce myocardial fiber injury in patients without preexisting cardiac diseases.     

为远期获益密切监测开腹行腹主动脉手术患者的心肌肌钙蛋白具有成本效益：一种决策分析模型

背景控制血管手术后心脏不良事件的策略在不断改进。早期发现和处理心肌缺血是提高手术后生存率的关键因素。心肌肌钙蛋白Ⅰ（cTnⅠ）的筛查是监测手术后心肌缺血性损伤的有效方法,并具有长期的预后价值。方法我们设计了一个马尔柯夫决策分析模型来评估手术后第0、1、2、3天常规监测cTnⅠ的成本效益,其目的还在于将手术后cTnⅠ〉1．5ng/ml的患者移入重症监护病房观察5天,严格控制目标心率（60～65次／分）,并进行严密监测和冠状动脉监护。根据已发表的文献所输入的主要变量如下：心肌梗死的概率0．049;监测cTnⅠ的成本为357美元;干预的成本和效率分别为13145美元和0．55。以寿命为时间轴,目标人群是平均年龄为65岁的行择期开腹腹主动脉手术的患者。此研究分析的费用来自第3方。结果相对于没有监测cTnⅠ的对照组,每个生命质量调整年用于监测cTnⅠ增加的成本效益为12641美元。单因素方差分析显示心肌梗死的可能性和干预的效能会影响成本效益。采用二次合并蒙特卡罗模拟分析行多因素敏感性分析显示,在每个生命质量调整年用低于50000美元的费用监测cTnⅠ,其获益率可达到90．75％。结论对于择期行开腹腹主动脉手术的住院患者,加强cTnⅠ监测并早期积极地使用β-受体阻滞剂会带来成本效益。     

Frequency of electrocardiographic changes indicating myocardial ischemia during elective cesarean delivery with regional and general anesthesia: detection based on continuous Holter monitoring and serum markers of ischemia

STUDY OBJECTIVE: To determine the frequency of electrocardiographic (ECG) changes and to assess the occurrence of myocardial ischemia during elective cesarean delivery with either regional or general anesthesia. DESIGN: Randomized, prospective, single-blinded clinical trial. SETTING: Large referral hospital. PATIENTS: 40 ASA physical status I and II term parturients. INTERVENTIONS: Patients were divided randomly into two groups as follows: the regional anesthesia group (group 1, n = 20) and the general anesthesia group (group 2, n = 20). MEASUREMENTS: In each case, continuous ECG was done using a 7-lead Holter monitor in the operating room, continuing for 24 hours after surgery. All Holter traces were analyzed by a study-blinded cardiologist. Blood samples were collected preoperatively (baseline) and at one, 5, and 24 hours postoperatively. Serum troponin T, creatinine kinase-MB, and myoglobin levels were measured. MAIN RESULTS: Two patients in group 1 (10%) and one patient in group 2 (5%) showed one mm ST-segment depression for two to 5 minutes. In all 40 cases, troponin T levels were in the normal range at all time points studied. In both groups, mean serum creatinine kinase-MB and myoglobin levels at one and 5 hours postoperatively were significantly higher than at baseline (P < 0.05). These high CK-MB and myoglobin levels were returned to normal ranges at the end of the study period; none of these women showed ST-segment changes. CONCLUSION: The ST-segment changes are not frequent in healthy women undergoing elective cesarean delivery during either regional or general anesthesia, and we found no evidence of myocardial injury.     

Influence of ischemic preconditioning and blood cardioplegia protection on postischemic endothelial activation in coronary bypass surgery

Summary Background Hypothermic ischemia in open heart surgery and cardiopulmonary bypass involve a postischemic in-flammatory reaction caused by an activation of leukocytes and endothelia with the systemic release of cytokines and adhesion molecules. The present study addresses the question, if an amelioration of postischemic endothelial activation in the heart could be achieved by means of cardioplegic protection or ischemic preconditioning. In a randomized prospective study patients underwent a normothermic preconditioning procedure either followed by crystalloid or blood cardioplegia during coronary bypass surgery. Methods Patients (n=28) were included and randomized in the study according to defined criteria: Group A received St. Thomas cardioplegia, group B cold blood cardioplegia. Ischemic precon-ditioning was performed twice at normothermia under a cardiopulmonary bypass (CPB) for 5 min followed by 10 min of reperfusion before coronary aortic bypass graft (CABG) using St. Thomas (group C) or blood cardioplegia (group D) hypothermic protection. In coronary sinus blood and arterial blood myocardial (creatine-kinase myoglobin [CK-MB]) and endothelial activation (endothelin, IL-6, IL-8, sE-selectin, soluble vascular adhesion molecule-1 [sVCAM-1], soluble intercellular adhesion molecule-1 [sICAM-1]) parameters were investigated 1, 3, 6, 9, 12, and 24 h after coronary reperfusion. Results 1) Parameters of myocardial injury (CK-MB, myoglobin) revealed increased levels at 1 h and 9 to 12 h after CABG. Levels at 12 h were lower in group B and D as compared to A and C. 2) Cytokines (IL-6, IL-8) showed increased levels 3 h after reperfusion with no difference between study groups. 3) Soluble adhesion molecules (E-selectin, VCAM-1, ICAM-1) were found increased in all groups 6 to 12 h after reperfusion. Lower levels were present in group D for E-selectin and VCAM-1. Conclusions The results indicate a sequence of cytokine and adhesion molecule release as a potential pathomechanism of myocardial reperfusion injury. Gradual decrease in the release of endothelial adhesion molecules in late myocardial injury was noted for blood cardioplegia and ischemic preconditioning. Amelioration of endothelial activation by means of preconditioning and blood cardioplegia may improve heart muscle recovery in open heart surgery with borderline ischemia time and organ dysfunction.      

Troponin I and myocardial injury in the ICU

Cardiac troponin I (cTnI) is a protein that is specific to heart muscle. Increased concentrations appear in serum after myocardial cell injury. cTnI was compared with creatinine kinase MB (CK MB), myoglobin and the 12-lead ECG for detection of myocardial injury in an unselected series of 109 medical and surgical ICU patients. Clinical observations and daily 12-lead ECG were recorded prospectively. Samples for cTnI, myoglobin and CK MB serum analysis were collected each day. Increased serum cTnI concentrations (> 0.1 microgram litre-1) were observed in 70.6% (n = 77) of the ICU group. Tachycardia, arrhythmia, hypotension and treatment with inotropic drugs were associated with higher concentrations. The standardized mortality ratio by APACHE III for the ICU sample was 0.98. All subjects in an unmatched control group of 98 medical unit emergency admissions without a primary cardiac diagnosis had serum cTnI concentrations < 0.1 microgram litre-1. We conclude that increased serum cTnI concentrations occur frequently in the ICU suggesting that there is a high incidence of cardiac injury in these patients.      

逆行性灌注浅低温氧合血心脏不停跳与冷血心脏停搏液对cTn I的影响

目的　对比研究逆行性灌注浅低温氧合血心脏不停跳与低温冷血心脏停搏液对外周血清心肌肌钙蛋白 I(c Tn I)的影响。　方法　将 18例双瓣膜置换术患者分为心脏不停跳组和心脏停搏组 ,观察围手术期外周血清c Tn I、肌酸激酶 (CK)、肌酸激酶同工酶 (CK- MB)及主动脉阻断前后用透射电子显微镜观察心肌超微结构变化。结果　心脏不停跳组主动脉开放后各个时相点 CK虽略低于心脏停搏组 ,但差别无显著性意义 (P>0 .0 5 ) ;主动脉开放后 6小时 CK- MB明显低于心脏停搏组 (P<0 .0 5 ) ,主动脉开放后各个时相点心脏不停跳组 c Tn I明显低于心脏停搏组 (P<0 .0 5 )。两组患者主动脉阻断前心肌超微结构均有轻度改变 ,主动脉阻断 90分钟心脏停搏组心肌超微结构损伤较心脏不停跳组明显。　结论　逆行性灌注浅低温氧合血心脏不停跳围手术期外周血清 c Tn I较低 ,可能与该方法使体外循环期间发生不可逆损伤的心肌细胞较少 ,心肌超微结构损伤较轻有关。