冠状动脉旁路移植术围手术期心肌梗死的诊断进展

冠状动脉旁路移植术(coronary artery bypass grafting，CABG)是治疗心肌缺血性疾病的主要手段。我国每年约2万例患接受CABG。一方面，通过搭桥恢复和改善缺血区心肌的血液供应．另一方面．手术本身会造成心肌的损害，严重时可造成围手术期心肌梗死(perioperative myocardic infarction,PMI)。PMI是CABG围手术期的主要并发症，其后果非常严重．因此PMI越来越受到重视。     

Troponin T levels in detection of perioperative myocardial infarction after coronary artery bypass surgery

OBJECTIVES: The present study was designed to evaluate the clinical relevance of serum cardiac troponinT (cTnT) assay in detection of perioperative myocardial infarction (PMI) after coronary artery bypass grafting (CABG). MATERIALS AND METHODS: The clinical utility of cTnT was compared to that of total CK, CKMB mass, CKMB activity and myoglobin. Serial venous blood samples were obtained before surgery and 4, 8, 16, 24, 48 and 72 hours after aortic unclamping (AU) in 42 patients who underwent CABG. We had 6 PMI patients, 24 patients with minor myocardial damage (MMD) and 12 without ischemic myocardial changes (no IMC). RESULTS: In discriminating no IMC from PMI the diagnostic sensitivity, specificity and the predictive values of cTnT were superior to that of CKMB mass, CKMB activity, myoglobin and total CK during 72 hours after AU. In discriminating MMD from PMI the diagnostic performance for CKMB mass and CKMB activity was superior to that of cTnT during the first 24 hours. After 24 hours the diagnostic performance for cTnT was improved but began to decline for CKMB isoenzymes. The discriminatory power of myoglobin measurements was lower than that of cTnT and CKMB mass. CONCLUSION: Our results indicate that troponin T is an accurate marker for the detection and monitoring of perioperative myocardial damage, especially 24 hours after AU.     

搭桥术后病人寒战的预防措施

体温是影响生命过程的一个重要因素。如机体内部温度严重偏离正常，则整个代谢功能将被破坏。手术病人的体温受环境温度、手术时间长短、暴露面积的大小、输入液体的多少及输入液体的温度、麻醉后肌肉松弛机体产热减少、抑制体温调节的防御反应等多方面因素的影响。冠脉搭桥手术后低体温常引起病人寒战，机体耗氧可增加2倍～3倍，造成氧供需失衡，尤其对冠心病人不利，常由此而引起心肌缺血。若体温小于35℃，心肌缺血的机会则增加3倍。     

搭桥术后病人寒战的预防措施

体温是影响生命过程的一个重要因素。如机体内部温度严重偏离正常,则整个代谢功能将被破坏。手术病人的体温受环境温度、手术时间长短、暴露面积的大小、输入液体的多少及输入液体的温度、麻醉后肌肉松弛机体产热减少、抑制体温调节的防御反应[1]等多方面因素的影响。冠脉搭桥手术后低体温常引起病人寒战,机体耗氧可增加2倍~3倍,造成氧供需失衡,尤其对冠心病人不利,常由此而引起心肌缺血。若体温小于35℃,心肌缺血的机会则增加3倍。并有证明中度低温(34℃)会引起心脏收缩与舒张机能异常[2]。然而体温问题却常被忽视而直接影响了病人恢复,严…     

Mass concentration of creatine kinase MB isoenzyme and lactate dehydrogenase isoenzyme 1 in diagnosis of perioperative myocardial infarction after coronary bypass surgery

Recent advances in methodology allow the mass concentration of creatine kinase MB isoenzyme (CK-MB), and of lactate dehydrogenase isoenzyme 1 (LD1) to be determined quickly and easily as routine, emergency tests. We evaluated these tests as diagnostic criteria of perioperative myocardial infarction (PMI) after coronary bypass surgery. These tests were compared with the usual measurements of CK-MB activity by immunoinhibition and LD1 by electrophoresis and with other biological markers of myocardial infarction such as total CK, total LD, and aspartate aminotransferase. Sixty-one patients who underwent coronary bypass grafting were followed pre- and postoperatively by enzyme determinations and electrocardiography; a subgroup was monitored by myocardial scintigraphy. CK-MB mass appeared to be the best marker of PMI during the first 48 h, although LD1 was the marker of choice from days 2 to 4.     

Thrombin generation during reperfusion after coronary artery bypass surgery associates with postoperative myocardial damage

BACKGROUND: Cardiopulmonary bypass and coronary artery bypass grafting (CABG) result in significant thrombin generation and activation of fibrinolysis. Thrombin contributes to myocardial ischemia-reperfusion injury in animal studies, but the role of thrombin in myocardial damage after CABG is unknown. OBJECTIVES: We measured thrombin generation and fibrin turnover during reperfusion after CABG to evaluate their associations with postoperative hemodynamic changes and myocardial damage. METHODS: One hundred patients undergoing primary, elective, on-pump CABG were prospectively enrolled. Plasma prothrombin fragment F(1+2) and D-dimer were measured preoperatively and at seven time points thereafter. Mass of the Mb fraction of creatine kinase (Ck-Mbm) and troponin T (TnT) were measured on the first postoperative day. RESULTS: Reperfusion induced an escalation of thrombin generation and fibrin turnover despite full heparinization. F(1+2) during early reperfusion associated with postoperative pulmonary vascular resistance index. F(1+2) at 6 h after protamine administration correlated with Ck-Mbm (r = 0.40, P < 0.001) and TnT (r = 0.44, P < 0.001) at 18 h postoperatively. Patients with evidence of myocardial damage (highest quintiles of plasma Ck-Mbm and TnT) had significantly higher F(1+2) during reperfusion than others (P < 0.002). Logistic regression models identified F(1+2) during reperfusion to independently associate with postoperative myocardial damage (odds ratios 2.5-4.4, 95% confidence intervals 1.04-15.7). CONCLUSIONS: Reperfusion caused a burst in thrombin generation and fibrin turnover despite generous heparinization. Thrombin generation during reperfusion after CABG associated with pulmonary vascular resistance and postoperative myocardial damage.     

非体外循环下冠状动脉搭桥术后病人的护理

冠心病病人属高危人群，常因年龄大、病程长、病情重，且多伴有其他疾病，术后并发症及病死率较一般人高。非体外循环下冠状动脉旁路移植是指应用药物和特殊手术器械以减弱跳动心脏的动度而进行的冠状动脉旁路移植术，这种手术避免了体外循环所带来的心、脑、肾、血液等脏器的损害及其相关的并发症，在适应证选择方面没有年龄限制，更适合于老年人和重症病人。2000年6月-2006年12月在非体外循环下为27例病人实施冠状动脉旁路移植，现将术后护理报告如下。     

非体外循环下冠状动脉搭桥术后病人的护理

冠心病病人属高危人群,常因年龄大、病程长、病情重,且多伴有其他疾病,术后并发症及病死率较一般人高.非体外循环下冠状动脉旁路移植是指应用药物和特殊手术器械以减弱跳动心脏的动度而进行的冠状动脉旁路移植术,这种手术避免了体外循环所带来的心、脑、肾、血液等脏器的损害及其相关的并发症,在适应证选择方面没有年龄限制,更适合于老年人和重症病人[1].     

体外循环术后早期血液流变学变化与术后谵妄的关系

目的研究体外循环(CPB)术后早期血液流变学变化并初步分析其与术后谵妄(POD)的关系。方法选择2010年6月至2011年6月在简阳市人民医院择期行CPB下单瓣膜置换术的风湿性瓣膜性心脏患者30例,采用静吸复合全身麻醉,浅低温高流量CPB。分别在麻醉输液实施前(T0),CPB毕(T1),CPB后1d(T2),CPB后2d(T3),CPB后3d(T4)经动脉各采血5mL,检测中切全血黏度(Mηb)、血浆黏度(ηP)。并于T2～T4用重症监护病房(ICU)精神错乱评估量表(CAM-ICU)测定患者的神经精神状态。结果27例患者纳入统计分析,其中9例患者在术后1～3d出现急性精神障碍,故以CAM-ICU分为POD组(9例)和未发生谵妄(NPOD)组(18例)。两组患者人口学资料差异无统计学意义(P>0.05)。POD组在T2～T4时间点Mηb水平均比NPOD组高,差异有统计学意义(P<0.05),而ηP水平在T1时间点比NPOD组高,差异有统计学意义(P<0.05)。结论 CPB后出现谵妄的患者表现出血液流变学的早期恶化,应加强对血液流变学的监测与治疗。     

心肌梗死患者经皮冠状动脉介入治疗前后局部室壁运动速度变化及其意义

目的　探讨心肌梗死患者经皮冠状动脉介入治疗 (PCI)对存活心肌功能恢复的影响。方法　对 2 6例接受PCI术的患者采用多普勒显像技术测定PCI术前后收缩期峰值速度 (Vs)、舒张早期峰值速度(Ve)、舒张晚期峰值速度 (Va)及Ve/Va值的变化。推断PCI术中顿抑心肌的存在及PCI后冬眠心肌的功能恢复。结果　前壁组PCI术后 8周Vs较术前显著升高 (P <0 .0 1) ,Ve/Va值较术前有所升高 ,但无统计学差异 ;下壁组中PCI术后 8周Vs、Ve/Va值较术前明显升高 (P <0 .0 5 ) ,Va较术前也明显降低 (P <0 .0 5 )。结论　PCI术后 72h ,心肌舒缩功能无明显变化 ,PCI术后 8周 ,出现局部收缩功能的改善 ,室壁也可出现舒张功能的改善 ,推测其与术前侧支循环的形成有关。     

单纯冠状动脉旁路移植术患者围术期输血的危险因素分析

目的分析影响单纯冠状动脉旁路移植术(CABG)患者围术期血制品使用的危险因素。方法回顾性分析行单纯CABG的4 022名患者围术期使用血制品的情况,单因素及多元Logistic回归分析影响CABG患者血制品使用的相关因素。结果 65.74%(2 644/4 022)的单纯CABG患者在围术期使用过血制品,包括红细胞、血浆、血小板。输血与未输血患者的院内死亡率及并发症发生率比较:未输血组分别为0.00%(0/1 378)、12.84%(177/1 378),输血组分别为0.98%(26/2 644)、26.06%(689/2 644)(P0.01)。Logistic回归多因素分析:性别、年龄、BMI、吸烟史、糖尿病史、病变冠脉数量、术者经验、体外循环、术前波立维使用为CABG患者围术期血制品使用的独立危险因素。结论掌握影响CABG患者围术期使用血制品的危险因素,利于合理、有效的输血治疗。     

Diabetes increases mortality after myocardial infarction by oxidizing CaMKII

Diabetes increases oxidant stress and doubles the risk of dying after myocardial infarction, but the mechanisms underlying increased mortality are unknown. Mice with streptozotocin-induced diabetes developed profound heart rate slowing and doubled mortality compared with controls after myocardial infarction. Oxidized Ca²⁺/calmodulin-dependent protein kinase II (ox-CaMKII) was significantly increased in pacemaker tissues from diabetic patients compared with that in nondiabetic patients after myocardial infarction. Streptozotocin-treated mice had increased pacemaker cell ox-CaMKII and apoptosis, which were further enhanced by myocardial infarction. We developed a knockin mouse model of oxidation-resistant CaMKIIδ (MM-VV), the isoform associated with cardiovascular disease. Streptozotocin-treated MM-VV mice and WT mice infused with MitoTEMPO, a mitochondrial targeted antioxidant, expressed significantly less ox-CaMKII, exhibited increased pacemaker cell survival, maintained normal heart rates, and were resistant to diabetes-attributable mortality after myocardial infarction. Our findings suggest that activation of a mitochondrial/ox-CaMKII pathway contributes to increased sudden death in diabetic patients after myocardial infarction.     

Propensity-matched analysis of the effect of preoperative intraaortic balloon pump in coronary artery bypass grafting after recent acute myocardial infarction on postoperative outcomes

Introduction

There is substantial variability in the preoperative use of intraaortic balloon pumps (IABPs) in patients undergoing coronary artery bypass grafting post myocardial infarction. The objective of this study is to determine the effect of preoperative IABPs on postsurgical outcomes in this subset of patients.

Methods

From 2007 to 2012, 877 patients underwent isolated coronary artery bypass post myocardial infarction. Four hundred and six patients were propensity-score matched based on the likelihood of receiving a preoperative balloon pump. Total blood transfusion requirements, composite in-hospital morbidity and/or mortality end point, total hours in the intensive care unit, and length of hospital stay were compared between the two groups.

Results

No significant differences in demographics, preoperative risk factors, intraoperative variables or length of hospital stay were found between patients with and without balloon pumps after propensity score matching. Compared to patients without balloon pumps, a higher percentage of patients with preoperative IABPs required transfusions. Patients with preoperative balloon pumps were more likely to have the composite end point of in-hospital morbidity (24.1% versus 12.8%, P <0.004), and increased hours in the intensive care unit (median hours: 69.0 versus 46.0, P <0.013) as compared to patients without balloon pumps.

Conclusions

The use of preoperative IABPs in patients undergoing isolated coronary artery bypass grafting after myocardial infarction is associated with increased transfusion requirements, increased in-hospital morbidity and longer postoperative intensive care unit stay as compared to patients without IABPs.     

冠脉搭桥术后桥管的超声检查方法研究

目的探讨经胸超声检查冠脉搭桥术后桥管的显像方法及血流状态。方法采用经胸超声冠脉血流显像与高频血管显像相结合对左乳内动脉原位转流至左前降支、大隐静脉-右冠状动脉及大隐静脉-左回旋支桥管进行检查。结果左乳内动脉桥管、大隐静脉-右冠状动脉及大隐静脉-左回旋支桥管显示率分别为100%、93.75%和20%。左乳内动脉及大隐静脉桥管的血流均为舒张期为主的双期血流;左乳内动脉桥管的舒张期血流速度及流速时间积分大于大隐静脉桥管（P〈0.05）。结论经胸超声是术后桥管检查的较好方法,可用于无创的评估术后桥管血流状态。     

高龄对冠状动脉旁路移植术围术期并发症的影响

目的探讨高龄(80岁)患者与60~70岁患者围术期并发症发病率是否存在差异。方法回顾性分析接受冠状动脉旁路移植术患者365例的临床资料,其中年龄80岁组52例,60~70岁组313例。观察比较两组术后主要并发症情况,包括:术后二次开胸、术后低心排、脑卒中、呼吸衰竭、术后需透析治疗的肾功能衰竭以及死亡。结果两组术后二次开胸发生率无显著差异(P0.05)。80岁组术后低心排(5.8%vs.0)、术后脑卒中(1.9%vs.0.3%)、术后呼吸衰竭(7.7%vs.1.0%)、术后需透析治疗的肾功能衰竭(3.8%vs.0)、死亡(11.5%vs.1.3%)的发生率均高于60~70岁组患者组,差异均有统计学意义(P0.05)。结论接受冠状动脉旁路移植术的患者中,年龄80岁者更容易出现术后低心排、术后脑卒中、术后呼吸衰竭、术后需透析治疗的肾功能衰竭及死亡。     

急诊冠状动脉搭桥术在急性心肌梗死治疗中的应用

目的探讨应用急诊冠状动脉搭桥术治疗急性心肌梗死(acute myocardial infarction,AMI)的可行性。方法对1999年1月至2003年2月我院46例AMI患者行急诊冠状动脉搭桥术(E—CABG)治疗进行回顾性分析。结果46例AMI患者中40例抢救成功,成功率为87．0％。结论E—CABG是治疗危重急性心肌梗死的有效方法,但需要具备一系列综合抢救措施、多学科的心脏中心以及一定数龟的常规冠状动脉搭桥术的技术和经验。     

急性心肌梗死血栓病变的血管内超声研究

目的　应用冠状动脉 (简称冠脉 )内超声 (intracoronaryultrasound ,ICUS)定量评价急性心肌梗死(AMI)患者冠脉内血栓病变。方法　AMI患者 86例 ,于经皮冠脉内介入 (PCI)前 ,对其中 69例患者行ICUS检测 ,并使用血栓面积及血栓所致面积狭窄等新参数。患者分为 3组 :急诊PCI组 (2 9例 )、溶栓组 (12例 )、延期PCI组 (2 8例 )。结果　急诊与延期PCI组冠脉闭塞分别占 44 .8% (13例 )、14 .2 % (4例 ) ,溶栓组无冠脉闭塞。急诊PCI组、溶栓组、延期PCI组血栓检出率分别为 93 .1%、75 .0 %、78.5 % ,差异无显著性意义 ;最狭窄段血栓面积分别为 (8.9± 3 .7)mm2 、(6.1± 3 .6)mm2 、(6.3± 3 .2 )mm2 ,急诊PCI组与另两组差异有显著性意义 (P <0 .0 5 ) ;血栓所致面积狭窄分别为 (4 5 .8± 12 .3 ) %、(3 8.4± 11.2 ) %、(4 0 .8± 12 .3 ) % ,急诊PCI组较溶栓组狭窄更重 (P <0 .0 5 ) ,但溶栓组与延期PCI组差别不大 ;血栓面积与最小腔面积比值分别为 4.9± 3 .3、2 .7± 2 .4、3 .1± 2 .7,急诊PCI组与另两组差异有显著性意义 (P <0 .0 5 ) ;血栓继发于斑块破裂或内膜增厚 ,在 3组间无明显差别。结论　ICUS可定量评价AMI时冠脉内血栓所致的面积狭窄 ,证明血栓是导致冠脉狭窄和闭塞的主要因素 ,溶栓成功患者冠脉