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.
目的:腎功能不全在急性冠脈綜合癥及其它心血管疾病中通常伴隨著較高的死亡率。而血漿尿素氮是反映血液動力學改變及腎臟灌注改變的非常敏感的指標。本試驗研究血漿尿素氮水平的高低對于急性ST段抬高型心肌梗塞患者死亡率的預測作用。方法:研究300名患急性ST段抬高型心肌梗塞患者長程的死亡率與入院時血漿尿素氮水平及住院時血漿尿素氮水平升高之間的關系。結果:在平均隨訪27個月,56(185%)個患者死亡。使用生存分析對于血漿尿素氮水平升高與血漿尿素氮水平正常兩組患者進行研究,用log-rank檢驗將兩組數據進行比較,有明顯統計學意義,Plt;0.001。結論:對于患急性ST段抬高型心肌梗塞患者的長期死亡率,入院時的血漿尿素氮水平是一個獨立的預測因素。BUN和BUN/creatinine比值的增高也能對患急性ST段抬高型心肌梗塞患者的長期死亡率提供一定的預測信息。同時,住院期間的BUN增高對于患急性ST段抬高型心肌梗塞患者的長期死亡率也能夠提供額外的預測信息。
截至2002年7月,急性心肌梗塞(acute myocardial infarction,AMI)治療的臨床證據如下:(1)改善AMI預后的證據:①血管緊張素轉換酶抑制劑(ACEI):1篇概述和1個(AMI 36 h到14 d內接受治療的患者)系統評價發現,血管緊張素轉換酶抑制劑和安慰劑相比,患者30 d后的死亡率明顯減少;血管緊張素轉換酶抑制劑和安慰劑相比,顯著增加了持續低血壓和腎功能不全.血管緊張素轉換酶抑制劑是提供給每一位存在AMI的患者,還是僅提供給有心衰征象的患者,目前尚無定論.②阿司匹林:1個系統評價發現,阿司匹林與安慰劑相比,能明顯減少1個月時的死亡率、非致死性再梗塞以及非致死性中風.③β受體阻滯劑:2個系統評價和1個后來的RCT發現,在AMI數小時內給予β受體阻滯劑與對照比較,顯著減少死亡率和再梗塞率.溶栓治療的RCT發現,美托洛爾的及時使用與延后使用相比,明顯減少患者6 d后再梗塞率以及復發的胸痛,但使用該藥6 d和1年間的死亡率沒有顯著差異.1個研究比較了在近期有心肌梗塞并且左室射血分數小于40%,或者基本沒有接受溶栓治療的患者中使用卡維地洛與安慰劑的RCT發現,盡管單獨的死亡率和復發性非致死性AMI在卡維地洛組中明顯較低,但1.3年后各種原因的死亡率以及由于心血管事件住院的聯合終點并沒有差異.④鈣離子拮抗劑:9個RCT發現,在AMI頭幾天范圍內,二氫吡啶和維拉帕米與安慰劑相比并不降低死亡率.1個左心衰的RCT發現有限的證據表明,在AMI的頭幾天給予硝苯地平與安慰劑比較可能會增加死亡率.⑤糖蛋白Ⅱb/Ⅲ a拮抗劑:2個大型的RCT發現,在AMI患者中聯合使用半劑溶栓劑和阿昔單抗與使用全劑量的溶栓劑相比,并沒有減少1個月時的死亡率,但可預防非致死性的心血管事件;用阿昔單抗聯合治療增加了出血并發癥,特別是顱外的出血.3個RCT發現,盡管加用阿昔單抗增加了出血的危險,但將阿昔單抗加到AMI患者最初的冠脈成型術或者支架中的益處仍有爭議.⑥溶栓之外的硝酸鹽制劑:2個溶栓時期使用硝酸鹽與安慰劑的RCT發現,死亡率沒有顯著差異.⑦沒有溶栓時的硝酸鹽制劑:1個在溶栓時代前所做試驗的系統評價發現,硝酸鹽較安慰劑顯著降低AMI患者的死亡率.⑧早期的經皮腔內冠狀動脈成形術與溶栓比較(在專業中心完成):2個系統評價發現,早期的經皮腔內冠狀動脈成形術與早期的溶栓相比明顯降低了急性心肌梗塞患者的死亡率以及30 d的再梗塞率.在非專業中心開展的有關比較經皮腔內冠狀動脈成形術與溶栓的試驗結果尚不清楚.⑨溶栓:1篇研究對象為AMI患者以及最初的心電圖上存在ST段上抬或者束支傳導阻滯的患者的試驗的概述發現,及時的溶栓治療(癥狀發作后的6 h內或許到12 h或者更長)與安慰劑比較顯著降低短期內的死亡率;溶栓與對照相比明顯增加了中風和大出血的危險.不同類型的溶栓劑之間相互比較的RCT的Meta分析發現,死亡率沒有顯著差異.(2)AMI繼發心源性休克的預后證據:①早期侵入性的心臟血管重建:1個以AMI 48 h內發生心源性休克患者為研究對象的RCT發現,早期侵入性的心臟血管重建與最初的單獨藥物治療相比顯著降低了6～12 d后的死亡率.1個樣本含量較小的RCT也得出了相似的結果,但差異并不顯著.②主動脈內的球囊反搏術:1個在AMI后的心源性休克患者中將主動脈內的球囊反搏術加溶栓與單用溶栓作比較的RCT摘要發現,6個月后的死亡率沒有顯著差異.③1個來自比較溶栓與不溶栓的RCT的AMI后心源性休克患者的亞組分析發現,21 d后的死亡率沒有顯著差異.④在心臟移植、早期心臟手術、正性肌力藥和血管擴張劑、肺動脈插管及左心室支持系統方面,尚未發現有關這些干預措施效果的RCT證據.