维持性血液透析患者心肌酶变化及其临床意义探讨

目的:测定维持性血液透析患者肌酸磷酸激酶-MB同工酶(CK-MB)、血清肌钙蛋白T(cTnT)、血清肌钙蛋白I(cTnI)的水平并探讨其预测心血管事件的价值。方法:连续收集2014年01月～2016年01月期间在我院维持性血液透析患者60例,另选取60例无肾功能损害的体检者作为对照组,同时检测两组肌酸磷酸激酶-MB同工酶(CK-MB)、血清肌钙蛋白T(cTnT)、血清肌钙蛋白I(cTnI)的水平,每6个月测定1次,随访2年,观察心血管事件发生情况,分析其与心肌酶水平关系。结果:与对照组相比,维持性血液透析组CK-MB水平无统计学差异,cTnT、cTnI的水平均升高(P 0. 01),60例维持性血液透析患者中cTnT阳性组心血管事件发生率53. 8%,cTnT阴性组心血管事件发生率10. 6%(P 0. 01); cTnI阳性组心血管事件发生率75. 0%,cTnI阴性组心血管事件发生率11. 5%(P 0. 01); cTnT及cTnI均升高5例,5例均发生心血管事件。结论:维持性血液透析患者血清cTnT及cTnI水平均升高,联合测试cTnT及cTnI可以更精确地找出维持性血液透析患者心血管事件发生的高危患者。     

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(cTnI)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12 1min ,阻断升主动脉 5 6min。灌注冷血停跳液保护心肌 ,平均每例搭桥 3 2支。围术期 2 0个时间点取静脉血标本 ,留血浆测cTnI和CK MB。术前及术后第 7d作标准 12导联心电图 (ECG)。结果　cTnI术前 5例升高者 ,停机后全部升高 ,第 8h达高峰 ,术后第 7d有 7例 (36 8% )仍高于正常 ;CK MB阻断升主动脉前正常 ,停机后升高 ,第 6h达高峰 ,术后第 2d全部恢复正常 ;2例发生围术期心梗 (PMI)者 ,整个围术期cTnI高于无PMI者 ;cTnI阻断升主动脉前已升高者 ,术后升高更显著。结论　cTnI与CK MB在CABG术后变化规律相似 ,但cTnI高于正常的持续时间长于CK MB ,有利于回顾性诊断 ;若阻断升主动脉前cTnI已升高 ,术后水平更高 ;cTnI诊断心肌损伤敏感性高于CK -MB。     

冠状动脉搭桥围术期心肌损伤标志物的临床意义

目的　探讨非体外循环与体外循环冠脉搭桥围术期血浆心肌损伤标志物的临床意义。方法　择期冠脉搭桥患者 4 6例 ,随机均分成不停跳非体外循环组 (Ⅰ组 )和体外循环组 (Ⅱ组 ) ,于麻醉诱导前 (T1)、术毕返ICU即刻 (T2 )、返ICU后 6h(T3 )、2 4h(T4)抽取中心静脉血样 5ml,用于测定肌酸激酶 (CK)、肌酸激酶同工酶蛋白质量 (CK MBmass)、肌钙蛋白T(cTnT)和肌红蛋白 (Myo) ;术前 1d及术毕返ICU后 1h ,术后第 1及第 2天晨做标准 12导联ECG ,以评价早期临床效果。结果麻醉诱导前所测各种心肌标志物中位数皆在正常范围内 ,术后均显著升高。CK MBmass、cTnT及Myo在返ICU后 6h达峰值 ,CK则在返ICU后 2 4h达峰值。其中Ⅱ组CK、CK MBmass及cTnT较Ⅰ组升高明显 ,并且其高于正常上限的比例也明显高于Ⅰ组 ,CK MBmass及cTnT在术毕返ICU即刻至 6h组间比较有极显著性差异 ,CK和Myo无论升高程度或高于正常上限比例两组术后比较无显著性差异。Ⅱ组有 1例心肌梗死 (PMI)在术后第 1天CK MBmass>30 μg /L ,cTnT最高 2 8μg/L。ECG缺血性改变在Ⅰ组 2例 ,同时都有CK MBmass>30 μg/L ,1例cTnT >1 0 μg/L ;Ⅱ组 7例ECG有缺血性改变 ,1例有CK MBmass>30 μg/L ,其余只有cTnT升高 >1 0 μg/L。两组患者手术时间 ,术后清醒时间 ,     

急性氟乙酰胺中毒患者心肌损伤的临床研究

目的 观察急性氟乙酰胺中毒患者血清心肌肌钙蛋白T(cTnT)的动态变化。方法 对92例急性氟乙酰胺中毒者进行血清cTnT、肌酸激酶(CK)和肌酸激酶同功酶(CK-MB)检测。结果 发病后3hcTnT阳性检出率为53.8％，明显高于CK(20％)、CK-MB(23．1％)；中毒后5dcTnT阳性检出率为69．2％，而CK和CK-MB仅为8．0％和4．0％。结论 (1)急性氟乙酰胺中毒者存在急性心肌损伤。(2)血清cTnT能早期确切诊断急性心肌损伤，有较宽的时间诊断窗．是心肌损伤早期诊断较敏感和特异的血清标志物。     

连续胸部硬膜外镇痛和静脉镇痛对老年冠心病患者术后心肌酶和肌钙蛋白T的影响

目的研究术后连续胸部硬膜外镇痛(TEA)和连续静脉镇痛(CVA)对老年冠心病患者术后心肌酶和肌钙蛋白T(cTnT)的影响。方法合并轻度冠心病行肺部手术的老年患者40例,术后随机均分为TEA组和CVA组,观察镇痛效果和镇静程度,对比术前术后心电图,并测定术前、术后第1、2、3天血清心肌酶活性和cTnT浓度。结果咳嗽时TEA组视觉模拟评分(VAS)低于CVA组(P<0.05)。CVA组的警觉/镇静(OAA/S)评分低于TEA组(P<0.05)。两组术后无ST段和T波的心肌梗死样衍变病例,也未发现病理性Q波。两组患者术后第1天肌酸激酶(CK)、肌酸激酶-MB(CK-MB)、乳酸脱氢酶(LDH)、β羟丁酸脱氢酶(HBD)的活性和cTnT水平都显著高于术前(P<0.05或P<0.01)。术后TEA组的cTnT水平显著低于CVA组(P<0.05),但都在正常值范围内。结论连续TEA效果优于CVA。两种镇痛方式对术后心肌酶的影响无差别,但连续TEA能降低术后cTnT的升高程度,提示对心肌有一定保护作用。     

牛磺酸对严重烧伤大鼠心肌损害的保护作用

目的　观察牛磺酸(Tau)对严重烧伤大鼠心肌损害的作用。　方法　将Wistar大鼠随机分为对照组(10只,不致伤)、烧伤组(60只)和Tau治疗组(60只)。后两组大鼠造成30%TBSAⅢ度烫伤(以下称烧伤),烧伤组伤后常规补液,Tau治疗组伤后腹腔注射Tau400mg/kg.于两组烧伤大鼠伤后1、3、6、12、24、48h检测其血浆中心肌肌钙蛋白T(cTnT)、丙二醛(MDA)的含量以及血浆、心肌组织中肿瘤坏死因子α(TNF- α)、血管紧张素Ⅱ(AngⅡ)的含量、心肌钙离子水平,用透射电镜观察心肌组织形态结构变化,并与对照组的上述指标进行比较。将烧伤组大鼠血浆TNF- α、AngⅡ检测结果分别与cTnT检测结果作相关性分析。　结果　烧伤组大鼠伤后3h起血浆cTnT水平较对照组(0.16±0. 03)μg/L显著升高(P<0. 01), 12h达峰值(6. 32±0. 41)μg/L, 48h仍显著高于对照组(P<0. 01).烧伤组伤后3—48h血浆MDA含量及心肌钙离子水平明显高于对照组(P<0. 01 );伤后6—48h血浆和心肌组织TNF- α含量显著高于对照组(P<0. 01);血浆及心肌组织中AngⅡ水平分别于伤后1—24h、3—24h明显高于对照组(P<0. 01).Tau治疗组上述指标在伤后多数时相点明显低于烧伤组(P<0. 01). 烧伤组大鼠伤后早期心肌肌丝断裂溶解、线粒体肿胀、嵴减少,Tau治疗组心肌组织接近正常。烧伤组     

电烧伤患者血清肌酸磷酸激酶变化的临床意义

目的　探讨血清肌酸磷酸激酶 (craetinephosphokinase ,CK)同工酶 (CK MM )的变化对电烧伤患者肌肉感染、坏死的诊断价值。　方法　高压电击伤与电弧烧伤各 17例分为A、B两组。A组为手术证实有明显的肌肉坏死者 ,B组为手术证实无肌肉坏死者。分别监测患者伤后、术前及术后血清CK MM的浓度 ,同期进行血、尿常规 ,肝、肾功能及创面细菌计数检查 ,并以 2 0例正常人血清CK MM值为对照。结果　 (1)A组伤后及扩创术后 1d血清CK MM的浓度显著升高 ,达正常对照组的 6倍 ;术后 3d 15例降至正常 ,2例因创面感染CK MM仍维持较高水平 ,经再次扩创抗感染处理后降至正常。其变化与手术所见、外周血白细胞计数变化及创面细菌计数相一致。 (2 )B组植皮术前及术后CK MM值轻度升高。　结论　CK MM可作为电击伤肌肉感染、坏死的监测指标 ,具有较高的特异性和敏感性。     

新生儿窒息后心肌损害的临床研究

目的 研究新生儿窒息后心肌损害敏感指标，以求早期诊断。方法 用血清心肌酶谱及多导心电记录仪和超声诊断仪等，对初生新生儿窒息后心肌损害进行有对照的前瞻性研究。结果 重度窒息组的血清心肌酶谱均升高，心电图异常率77．8％，超声心电图检查均发现异常；轻度窒息组的血清心肌酶谱α—HBD升高100％，CK升高82．6％，LDH升高73．9％，AST升高65．2％，心电图检查均无异常，超声心动图检查42．9％异常；对照组未见异常。结论 缺氧和酸中毒是新生儿窒息后心肌损害的直接原因；心肌酶谱变化的敏感性高，可用于新生儿窒息后心肌损害的早期诊断。     

家兔氢氟酸烧伤心肌损害的实验研究

目的　研究氢氟酸烧伤对心肌的影响 ,提高对氢氟酸导致氟中毒的认识。　方法　采用新西兰白兔 2 %TBSAⅢ度氢氟酸烧伤模型 ,观察各时相点心肌和相关酶谱指标的改变 ,以及病理形态学变化。　结果　 ( 1)伤后心肌各项酶含量较伤前明显增高 (P <0 .0 1)。 ( 2 )血清心肌酶含量增高峰值均在 48h以内出现。各时相点心肌酶谱含量的差异均有非常显著性意义 (P <0 0 1)。( 3)血清心肌酶含量以CPK增幅最大 ,增加了 97.5 %。而LDH、AST、CK -MB分别增加了 81.9%、76 .1%和 6 0 .3%。 ( 4)病理形态学检查发现 ,光镜下见心肌纤维颗粒变性、灶性坏死 ,心肌间质出血 ,并伴有中性粒细胞、淋巴细胞浸润。电镜观察心肌细胞内肌原纤维减少或消失 ,细胞水肿严重 ,线粒体肿胀、嵴消失 ,血管内皮细胞肿胀 ,电子密度极低 ,呈大泡状 ,肌细胞核变形。　结论　氢氟酸烧伤后对心肌有一定程度损害 ,心肌和心肌相关酶谱含量的改变 ,反映了氢氟酸致伤后的心肌损伤程度 ,在抢救氢氟酸烧伤、氟中毒时应监测心肌酶谱及心电图等指标 ,注意保护心脏的功能     

维持性血液透析患者血清心肌肌钙蛋白T和C反应蛋白水平与预后的关系

目的探讨维持性血液透析(MHD)患者血清心肌肌钙蛋白T(cTnT)和C反应蛋白(CRP)对其心脑血管疾病及死亡的预测价值。方法选择在北京医院进行维持性血液透析的患者106例。检测透析前血清cTnT、CRP、Scr、白蛋白等,计算Kt／V,并行心电图检查。以第 1次取血时间为研究的开始,记录随访期间患者的死亡情况及发生的心脑血管事件。结果 106 例MHD患者中,血清cTnT阳性28例(26．42％),血清CRP阳性32例(30．19％),2者均阳性16 例(15．09％)。平均随访(16．59±9．44)月,随访期间死亡22例(20．75％),发生心脑血管事件38 例(35．85％)。Logistic回归分析显示血清cTdT水平与CRP及Scr显著相关;血清CRP水平与年龄、cTnT及Kt／V显著相关。血清cTnT阳性组的病死率和心脑血管事件发生率比阴性组显著上升,P值分别为0．001和0．023。血清CRP阳性组与阴性组也表现同样结果。2者均阳性组与其他3组相比,病死率和心脑血管事件发生率也显著上升。生存分析显示,2者的单独阳性和联合阳性都对生存有明显影响。结论维持性血液透析无急性冠脉综合征的患者中,部分患者血清 cTnT水平升高。血清cTnT阳性与血清CRP及Scr水平相关。血清cTnT及CRP阳性组总病死率及心脑血管事件发生率均明显高于2者的阴性组。     

非体外循环冠状动脉旁路移植术的心肌保护

目的　比较非体外循环心脏跳动下冠状动脉旁路移植术 (OPCAB)与常规体外循环下冠状动脉旁路移植术 (CABG)的心肌保护效果。方法　将 70例冠状动脉粥样硬化病人分成 2组 ,行非体外循环冠状动脉旁路移植术组 (非体外循环组 35例 ) ,间断冷氧合血心脏停搏液冠状动脉旁路移植术组 (冷血停跳组 35例 )。 2组病人术前心功能、年龄、性别、体质量差异无统计学意义 ;各组于围术期不同时点分别抽血测定肌酸激酶同工酶 (CK MB)、心肌肌钙蛋白T(cTnT)。关胸前每组各随机取 2例病人心尖区心肌 ,行心肌超微结构观察。结果　非体外循环组术中、术后各时间点CK MB、cTnT与冷血停跳组比较差异有显著性 (P <0 0 5 ) ;非体外循环组心肌超微结构表明心肌保护效果明显优于后者。结论　非体外循环组心肌保护效果优于冷血停跳组。与CK MB相比 ,cTnT是评价心肌损害的更特异、更敏感的指标。     

Effects of autotransfusion of mediastinal shed blood on biochemical markers of myocardial damage in coronary surgery

BACKGROUND: Previous studies have shown conflicting results regarding the effect of autotransfusion of mediastinal shed blood after coronary artery bypass grafting (CABG) on the serum levels of myocardial band (MB) isoenzymes of creatine kinase (CK-MB) and cardiac troponins. The effect of autotransfusion on serum levels of human heart fatty acid binding protein (H-FABP), another marker of myocardial necrosis, has not been studied. The aim of the present study was to investigate the effects of autotransfusion of mediastinal shed blood on the serum levels of CK-MB, cardiac troponin T (cTnT), and H-FABP after uncomplicated primary CABG. METHODS: Fifty patients were randomized to post-operative autotransfusion of mediastinal shed blood or no autotransfusion. Blood samples for the analysis of the biochemical markers of myocardial damage were drawn pre-operatively and 1, 4, 12, 24, 48, and 72 h after the termination of cardiopulmonary bypass. Samples from the mediastinal shed blood were collected after 1 and 4 h. RESULTS: The levels of the biochemical markers of myocardial injury were all markedly elevated in mediastinal shed blood. Autotransfusion did not significantly affect the serum levels of cTnT or H-FABP. However, during the early post-operative hours, there was a trend towards a higher level of cTnT and H-FABP in the autotransfusion group. During the first 24 h after surgery, the autotransfusion group had a significantly higher serum level of CK-MB. CONCLUSION: Post-operative autotransfusion of mediastinal shed blood may contribute to elevated serum levels of biochemical markers of myocardial injury.     

Peri-operative myocardial injury in patients undergoing surgery for critical limb ischaemia.

INTRODUCTION: Although up to a half of patients undergoing abdominal aortic aneurysm (AAA) repair suffer myocardial injury, as indicated by a rise in cardiac troponin I (cTnI), this is infrequently accompanied by a rise in creatine kinase (CK)-MB fraction or electrocardiogram (ECG) changes. This study compares for the first time peri-operative cTnI, CK-MB and ECG changes in patients undergoing surgery for critical lower limb ischaemia (CLI). METHODS: Twenty-nine patients (20 men, median age 75 [range, 57-95] years) were studied prospectively. cTnI, CK/CK-MB ratio and ECG were performed pre-operatively and on post-operative days 1, 2 and 3. RESULTS: Eleven (38%) patients had an elevated cTnI >0.5 ng/ml. Five (17%) patients had an elevated CK-MB fraction >4% and all of these patients had an elevated cTnI. Eleven (38%) patients had ischaemic changes on ECG including seven of 11 (64%) patients with elevated cTnI and all five patients with elevated CK-MB fraction. There was no relationship between pre-operative cardiac status, antiplatelet use or type of anaesthesia and post-operative cTnI rise. Patients with a cTnI rise were younger (p=0.01), and were more likely to have presented with gangrene (p=0.04) and have a longer operation time (p=0.01) than patients who did not demonstrate a cTnI rise. Four patients developed clinically apparent cardiac complications: cardio-pulmonary arrest (n=1), cardiogenic shock (n=1), acute CCF (n=1) and rapid atrial fibrillation (n=1). Survival at 6 months was 26 of 29 (90%) patients. CONCLUSION: These data demonstrate that over a third of patients operated for CLI sustain peri-operative myocardial injury, many of which are not clinically apparent. Pre-operative medical optimisation may improve prognosis in this group of patients.     

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。     

Early identification of permanent myocardial damage after coronary surgery is aided by repeated measurements of CK-MB

OBJECTIVE: ECG diagnosis of myocardial infarction after cardiac surgery is associated with major pitfalls and enzyme diagnosis is interfered by unspecific elevation unrelated to permanent myocardial injury. Sustained release of troponin-T is a marker of permanent myocardial injury if renal function is maintained. However, early identification of perioperative myocardial infarction is desirable and therefore the usefulness of creatine kinase monobasic (CK-MB) kinetics to detect myocardial injury early after coronary surgery was investigated. DESIGN: Two hundred and eighty-six patients undergoing coronary surgery were studied with respect to release of enzymes and troponin-T preoperatively and postoperatively 3 and 8 h after unclamping the aorta, and every morning postoperative days 1-4. RESULTS: CK-MB peak was found at 3 h (n = 145), 8 h (n = 103) and 16-20 h after unclamping (n = 38). Depending on when the CK-MB peak was recorded different demographic and perioperative characteristics were found. A sustained release of troponin-T was characteristic for the group with the CK-MB peak at 16-20 h after unclamping. CONCLUSION: If CK-MB is measured only once it may be advisable to do it on the first postoperative morning as these measurements provided the best discrimination between patients with and without sustained elevation of troponin-T. However, repeated sampling provides additional information that aids in the early identification of permanent myocardial injury particularly in patients with borderline elevations of CK-MB.     

lncRNA-MALAT1/miRNA-145在舒芬太尼预处理减轻大鼠心肌缺血-再灌注损伤中的作用

目的探讨长链非编码RNA(lncRNA)肺腺癌转录子1(MALAT1)在舒芬太尼预处理减轻大鼠心肌缺血-再灌注损伤(MIRI)中的作用。方法 SPF级大鼠36只,体重180~200 g,随机分为三组:假手术组(Sham组),缺血-再灌注损伤组(IR组),缺血-再灌注损伤+舒芬太尼组(SUF组),每组12只。IR组和SUF组建立大鼠心肌缺血-再灌注损伤模型,SUF组于再灌注前10 min尾静脉注射舒芬太尼1μg/kg,Sham组和IR组注射等体积生理盐水。再灌注后2 h检测大鼠血清中肌酸激酶同工酶MB(CK-MB)、心肌肌钙蛋白T(cTnT)和乳酸脱氢酶(LDH)活性,同时检测大鼠心肌梗死面积;检测心肌细胞凋亡相关蛋白Bcl-2、Bax、Cleaved-caspase-3和Caspase-3含量;检测大鼠心肌组织中lncRNA-MALAT1和miRNA-145的相对表达量。结果与Sham组比较,IR组和SUF组CK-MB和cTnT浓度明显升高,LDH活性明显增强,心肌梗死面积明显增大,心肌组织中Bax/Bcl-2比值明显降低,Cleaved-caspase-3蛋白含量明显升高,lncRNA-MALAT1相对表达量明显升高,而miRNA-145相对表达量明显降低(P<0.05)。与IR组比较,SUF组CK-MB和cTnT浓度明显降低,LDH活性明显减弱,心肌梗死面积明显减小,Bax/Bcl-2比值明显升高,Cleaved-caspase-3蛋白含量明显降低,lncRNA-MALAT1相对表达量明显降低,miRNA-145相对表达量明显增加(P<0.05)。结论舒芬太尼预处理能减轻大鼠心肌缺血-再灌注损伤程度,其机制可能与抑制lncRNA-MALAT1、升高miRNA-145表达有关。     

Factors associated with increased serum levels of cardiac troponins T and I in chronic haemodialysis patients: Chronic Haemodialysis And New Cardiac Markers Evaluation (CHANCE) study.

BACKGROUND: Serum concentrations of the cardiac troponins (cTn) T and I, specific markers of myocardial injury, are frequently elevated in haemodialysis patients. The clinical relevance of this is unclear. The aim of this study was to investigate factors associated with increased serum levels of cTn in haemodialysis patients. METHODS: We included in this cross-sectional study 258 chronic haemodialysis patients (150 men, age 60+/-15 years) without acute coronary symptoms. Clinical data, echocardiographic hypertrophy, biochemical status, and haemodialysis regimen were evaluated for each patient. Pre-dialysis serum cTnT (Elecsys, Roche), cTnI (Stratus and RXL, Dade-Berhing), and CK-MB (Stratus, Dade-Berhing) concentrations were determined. Logistic regression was the principal method of analysis. RESULTS: Pre-dialysis levels of cTnT >0.1 ng/ml (n=48, 18.6% of patients) were associated with age (P<0.001), diabetes (P<0.005), history of ischaemic heart disease (P<0.05), and left ventricular hypertrophy (P<0.05). In multivariate analysis, age odds ratio ((OR) 1.04), diabetes (OR 4.9), and indexed left ventricular mass (OR 1.01) were found to be independently associated with cTnT concentration above the threshold. Only six patients had cTnI-Stratus levels >0.6 ng/ml. cTnI-RXL levels >0.3 ng/ml (n=13, 5.0%) were associated with age (P=0.05) and hypercholesterolaemia (P<0.05). Only age (OR 1.06) remained associated in multivariate analysis. CONCLUSION: Elevated baseline serum levels of cardiac troponins were associated with cardiovascular risk factors, history of ischaemic heart disease and left ventricular hypertrophy in asymptomatic chronic haemodialysis patients.     

Long-term prognostic value of asymptomatic cardiac troponin T elevations in patients after major vascular surgery.

BACKGROUND: Cardiac troponin T (cTnT) is a sensitive and specific marker for myocardial injury, but elevations of cTnT without clinical evidence of ischemia and persistent or new electrocardiographic (ECG) abnormalities are common in patients undergoing major vascular surgery. We explored the long-term prognostic value of cTnT levels in these patients. METHODS: A follow-up study was conducted between 1996-2000 in 393 patients who underwent successful aortic or infrainguinal vascular surgery and routine sampling of cTnT. Patients were followed until May 2003 (median of 4 years [25th-75th percentile, 2.8-5.3 years]). Total creatine kinase (CK), CK-MB, and cTnT were routinely screened in all patients, and included sampling after surgery and the mornings of postoperative days 2, 3 and 7. Electrocardiograms were also routinely evaluated for sign of ischemia. An elevated cTnT was defined as serum concentrations >/=0.1 ng/ml in any of these samples. All-cause mortality was evaluated during long-term follow-up. RESULTS: Eighty patients (20%) had late death. The incidence of all-cause mortality (41% vs. 17%; p<0.001) was significantly higher in patients with an elevated cTnT level compared to patients with normal cTnT. After adjustment for baseline clinical characteristics, the association between an elevated cTnT level and increased incidence of all-cause mortality (adjusted hazard ratio, 1.9; 95% CI, 1.1-3.1) persisted. Elevated cTnT had significant prognostic value in patients with and without renal dysfunction, abnormal levels of CK-MB, and in patients with transient ECG abnormalities. CONCLUSIONS: Elevated cTnT levels are associated with an increased incidence of all-cause mortality in patients undergoing major vascular surgery.     

远程缺血预处理对心肺转流心脏瓣膜置换术患者心肌损伤的保护作用

目的探讨远程缺血预处理(RIPC)对心肺转流(CPB)下心脏瓣膜置换术患者心肌损伤的影响。方法 CPB心脏瓣膜置换术患者40例,随机均分为研究组(E组)和对照组(C组)。E组于麻醉诱导插管完毕稳定5min后,应用骨科气压止血带给左上肢加压至35kPa,5min后,减压至0kPa,5min后重复加压,共4次,而C组只固定止血带,不加压。分别于麻醉诱导插管完毕稳定5min后(T1)、主动脉开放30min后(T2)、CPB停止后2h(T3)、术后12h(T4)、术后24h(T5)测颈内静脉血心肌肌钙蛋白I(cTnI)及肌酸激酶同工酶(CK-MB)浓度。结果与T1相比,两组cTnI浓度在T2时升高达峰值,随后持续下降;两组CK-MB浓度在T2时开始升高,T3时升高达峰值,随后持续下降。E组cTnI、CK-MB浓度在T2～T5时均明显低于C组(P<0.05或P<0.01)。结论 RIPC可降低CPB下心脏瓣膜置换术患者围术期cTnI、CK-MB的释放,减少围术期血管活性药物用量,减轻心肌的缺血-再灌注损伤,具有一定的心肌保护作用。     

Serum troponin-I as an indicator of clinically significant myocardial injury in paediatric trauma patients

Myocardial injury is a cause of mortality in paediatric trauma, but it is often difficult to diagnose. The objectives of this pilot study were to (1) determine the prevalence of elevated cardiac troponin I (TnI) in paediatric trauma patients and (2) to determine whether elevated TnI correlates with clinically significant myocardial injury, defined as abnormalities on echocardiogram (ECHO) and/or electrocardiograms (ECG). To this end, we investigated a convenient sample size of 59 paediatric trauma patients with an Injury Severity Score (ISS)>12. TnI and creatine kinase-MB (CK-MB) were measured on admission, at then at regular intervals until TnI had normalized. Patients with elevated TnI levels had an ECHO performed within 24h of admission and underwent daily ECGs until TnI normalized. Elevated serum TnI was found in n=16/59 (27%; 95% CI: 18-40%) patients and was associated with elevated CK-MB in all cases. Abnormal ECHOs were seen in 4/16 patients with elevated TnI, but peak TnI values did not correlate with abnormalities on ECHO (p=0.23). Only 1 patient had a clinically significant, albeit mild, decrease in cardiac function. All ECGs were normal. Patients with elevated TnI were more likely to be intubated (p=0.04), to have higher Injury Severity Scores (p=0.02), required more resuscitation fluid (p=0.001), and to have thoracic injuries (p<0.001). Our data indicates that the prevalence of elevated TnI in paediatric trauma patients is 27%; and whilst elevated TnI reflects overall trauma severity, it is frequently elevated without a clinically significance myocardial injury. Hence, large scale studies are required to determine if an elevated threshold TnI value can be identified to accurately diagnose severe myocardial injury in paediatric trauma.