Background Mortality and morbidity of acute myocardial infarction remains high. Intravenous magnesium started early after the onset of myocardial infarction is a promising adjunctive treatment that may limit infarct size, prevent serious arrhythmias, and reduce mortality. Several earlier trials and meta-analyses demonstrated a mortality rate reduction with magnesium treatment, but one mega trial found no benefit. Objective To examine the effect of intravenous magnesium versus control on early mortality and morbidity, stratified by time since onset of symptoms (lt;6 hours, 6+ hours), use of thrombolysis (used, not used), dose of magnesium used (lt;75 mmol, 75+ mmol). Search strategy We search the Cochrane controlled trial register (CCTR) of Cochrane Library, Medline and Embase. We also search Chinese Biomedical Disk (CBM disk) to identify the Chinese trials. Each database will be searched from its starting date to the first-half year of 2002. Selection criteria All randomized controlled trials that compared intravenous magnesium with placebo in the presence or absence of fibrolytic therapy in addition to routine treatment are eligible if they reported mortality and clinical events within 35 days of onset, regardless of language. Methods of review A data abstraction form will be specifically developed to extract information from the eligible articles. The quality assessment of RCT will be focused on method of treatment assignment, blinding of participants and investigators, control of selection bias after treatment assignment. The selection of studies, data extraction and assessment of methodological quality will be performed independently by two reviewers. Disagreements will be resolved through discussion, when necessary, in consultation with a third reviewer. Publication bias, heterogeneity and sensitivity analysis will be performed. The odds ratio (OR) will be used to pooling the effect if appropriate.
Objective To evaluate the diagnostic value of human heart-type fatty acid-binding protein for early detection of acute myocardial infarction (AMI). Methods Studies involving this biomarker were identified from MEDLINE, EMbase, CBM and VIP (1970 to 2006). Relevant journals (1980 to 2006) were also handsearched. The quality of the included studies was assessed using the QUADAS tool. Data extraction and analysis were conducted by software of EXCEL2003 and Metadisc. Results We included 13 studies, which were heterogeneous (P=0, I2=58.5%). Five studies (n=396) included in the group assessed the test at the first three hours after chest pain onset. These studies were homogeneous (P= 0.49, I2=0). The pooled sensitivity was 0.86 ( 95%CI 0.80 to 0.91), the pooled specificity was 0.76( 95%CI 0.80 to 0.91), and the area under the curve was 0.88 (SE=0.032 3). In the group of 0 to 6 hours after chest pain onset, 10 included studies (n=1 175) were heterogeneous (P=0, I2=69%). The pooled sensitivity was 0.86 (95%CI 0.83 to 0.89), the pooled specificity was 0.79 (95%CI 0.76 to 0.82), and the area under the curve was 0.92 (SE=0.019). In the group of 6 to 12 hours after chest pain onset, 4 included studies (n=215) were homogeneous (P=0.56, I2=0). The pooled sensitivity was 0.97 (95%CI 0.91 to 0.99), the pooled specificity was 0.52 (95%CI 0.42 to 0.61), and the area under the curve was 0.810 with (SE=0.152 2). In the group of 0 to 12 hours after chest pain, 11 included studies (n=1 352) were heterogeneous (P=0.56, I2=59%). The pooled sensitivity was 0.88 (95%CI 0.84 to 0.89), the pooled specificity was 0.75 (95%CI 0.71 to 0.78), and the areas under the curve was 0.91 (SE=0.016 4). Conclusions In this systematic review, we found that H-FABP has an acceptable diagnostic accuracy within 3 hours after the onset of symptoms, and within 12 hours after the onset of symptoms, H-FABP has a high diagnostic efficacy. So H-FABP may be a new symbol for the early diagnosis of AMI.
截至2002年7月,急性心肌梗塞(acute myocardial infarction,AMI)治疗的临床证据如下:(1)改善AMI预后的证据:①血管紧张素转换酶抑制剂(ACEI):1篇概述和1个(AMI 36 h到14 d内接受治疗的患者)系统评价发现,血管紧张素转换酶抑制剂和安慰剂相比,患者30 d后的死亡率明显减少;血管紧张素转换酶抑制剂和安慰剂相比,显著增加了持续低血压和肾功能不全.血管紧张素转换酶抑制剂是提供给每一位存在AMI的患者,还是仅提供给有心衰征象的患者,目前尚无定论.②阿司匹林:1个系统评价发现,阿司匹林与安慰剂相比,能明显减少1个月时的死亡率、非致死性再梗塞以及非致死性中风.③β受体阻滞剂:2个系统评价和1个后来的RCT发现,在AMI数小时内给予β受体阻滞剂与对照比较,显著减少死亡率和再梗塞率.溶栓治疗的RCT发现,美托洛尔的及时使用与延后使用相比,明显减少患者6 d后再梗塞率以及复发的胸痛,但使用该药6 d和1年间的死亡率没有显著差异.1个研究比较了在近期有心肌梗塞并且左室射血分数小于40%,或者基本没有接受溶栓治疗的患者中使用卡维地洛与安慰剂的RCT发现,尽管单独的死亡率和复发性非致死性AMI在卡维地洛组中明显较低,但1.3年后各种原因的死亡率以及由于心血管事件住院的联合终点并没有差异.④钙离子拮抗剂:9个RCT发现,在AMI头几天范围内,二氢吡啶和维拉帕米与安慰剂相比并不降低死亡率.1个左心衰的RCT发现有限的证据表明,在AMI的头几天给予硝苯地平与安慰剂比较可能会增加死亡率.⑤糖蛋白Ⅱb/Ⅲ a拮抗剂:2个大型的RCT发现,在AMI患者中联合使用半剂溶栓剂和阿昔单抗与使用全剂量的溶栓剂相比,并没有减少1个月时的死亡率,但可预防非致死性的心血管事件;用阿昔单抗联合治疗增加了出血并发症,特别是颅外的出血.3个RCT发现,尽管加用阿昔单抗增加了出血的危险,但将阿昔单抗加到AMI患者最初的冠脉成型术或者支架中的益处仍有争议.⑥溶栓之外的硝酸盐制剂:2个溶栓时期使用硝酸盐与安慰剂的RCT发现,死亡率没有显著差异.⑦没有溶栓时的硝酸盐制剂:1个在溶栓时代前所做试验的系统评价发现,硝酸盐较安慰剂显著降低AMI患者的死亡率.⑧早期的经皮腔内冠状动脉成形术与溶栓比较(在专业中心完成):2个系统评价发现,早期的经皮腔内冠状动脉成形术与早期的溶栓相比明显降低了急性心肌梗塞患者的死亡率以及30 d的再梗塞率.在非专业中心开展的有关比较经皮腔内冠状动脉成形术与溶栓的试验结果尚不清楚.⑨溶栓:1篇研究对象为AMI患者以及最初的心电图上存在ST段上抬或者束支传导阻滞的患者的试验的概述发现,及时的溶栓治疗(症状发作后的6 h内或许到12 h或者更长)与安慰剂比较显著降低短期内的死亡率;溶栓与对照相比明显增加了中风和大出血的危险.不同类型的溶栓剂之间相互比较的RCT的Meta分析发现,死亡率没有显著差异.(2)AMI继发心源性休克的预后证据:①早期侵入性的心脏血管重建:1个以AMI 48 h内发生心源性休克患者为研究对象的RCT发现,早期侵入性的心脏血管重建与最初的单独药物治疗相比显著降低了6~12 d后的死亡率.1个样本含量较小的RCT也得出了相似的结果,但差异并不显著.②主动脉内的球囊反搏术:1个在AMI后的心源性休克患者中将主动脉内的球囊反搏术加溶栓与单用溶栓作比较的RCT摘要发现,6个月后的死亡率没有显著差异.③1个来自比较溶栓与不溶栓的RCT的AMI后心源性休克患者的亚组分析发现,21 d后的死亡率没有显著差异.④在心脏移植、早期心脏手术、正性肌力药和血管扩张剂、肺动脉插管及左心室支持系统方面,尚未发现有关这些干预措施效果的RCT证据.