Effects of glucose-insulin-potassium infusion on myocardial perfusion and left ventricular remodeling in patients treated with primary angioplasty for ST-elevation acute myocardial infarction

The role of glucose-insulin-potassium (GIK) infusion in the management of acute coronary syndrome is controversial. Limited data are available on the effects of adjunctive high-dose GIK (30% glucose, 50 IU of insulin, 80 mEq of potassium chloride infused at 1.5 ml/kg/hour over 24 hours) on myocardial perfusion and left ventricular (LV) remodeling in patients treated with primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction. In this prospective study, 73 patients were randomized to receive GIK infusion (n = 40) or saline (placebo, n = 33) in addition to standard therapy. The primary end points were myocardial perfusion after PCI and LV remodeling at 6 months. Thrombolysis In Myocardial Infarction frame count and myocardial blush grade were evaluated before and after reperfusion treatment. LV end-diastolic and end-systolic volumes, ejection fraction, and wall motion score index were assessed in each patient after PCI and after 6 months. Although no differences in final Thrombolysis In Myocardial Infarction flow were observed between the 2 groups, myocardial blush grade 3 was more frequently achieved in the GIK group (p <0.05). At 6 months, ventricular remodeling was more often observed in the control group (24% vs 3%, p <0.05). In conclusion, GIK infusion in adjunct to primary PCI in patients with ST-segment elevation myocardial infarction was safe, improved myocardial perfusion after revascularization, and was associated with less LV remodeling at follow-up.     

替罗非班在ST段抬高型急性心肌梗死溶栓治疗患者中的疗效

目的观察替罗非班在ST段抬高型急性心肌梗死溶栓治疗患者中的临床疗效及安全性。方法选择58例ST段抬高型心肌梗死并采取溶栓治疗患者,随机分为两组,对照组（n=28）给予常规尿激酶溶栓及阿司匹林、氯吡格雷、β受体阻滞剂、他汀类药物等治疗,治疗组（n=30）在对照组治疗药物的基础上加用替罗非班治疗,比较两组患者药物治疗后的临床疗效、院内及院外随访期间的心血管事件发生率。结果治疗组总有效率为86.7%,对照组总有效率为67.9%,两组治疗方法的总有效率有统计学差异（P〈0.05）;与对照组比较,治疗组未增加大出血等院内及院外心血管事件（P均〉0.05）。结论 ST抬高型心肌梗死溶栓治疗并加用替罗非班治疗临床疗效优于单纯溶栓治疗,未增加患者近期及远期心脑血管事件。     

Prehospital thrombolytic therapy with tenecteplase in patients with ST-elevation myocardial infarction

We carried out prehospital thrombolytic therapy (TLT) with tenecteplase in 24 patients with ST-elevation myocardial infarction (MI) at the background of standard concomitant therapy with unfractionated heparin, aspirin, and clopidogrel and analyzed clinical course of MI, ECG dynamics, systolic left ventricular function according to echocardiography. In 20 patients coronary angiography was performed after TLT. Mean symptom - needle time was 113 min. In 14 patients (58%) TLT was carried out within 2 hours after appearance of symptoms. In 19 patients the course of disease was uncomplicated. Electrocardiographic criteria of effective reperfusion were registered in 14 patients (58%), angiographic criteria - in 13 patients (65% of subjected to angiography). Percutaneous intervention was performed in 18 patients (75%). Systolic left ventricular dysfunction was revealed in 5 patients (21%), aborted MI - in 4 patients. Significant correlation was found between aborted MI (r=0,38, p=0,034) and uncomplicated MI (r=0,40, p=0,027) and performance of TLT during first 2 hours. There were no hemorrhagic complications. Results of the study evidence for high efficacy of prehospital thrombolysis with tenecteplase and real possibility of its use under conditions of existing system of organization of urgent cardiological aid.     

急性ST段抬高型心肌梗死溶栓治疗的最新进展

经皮冠状动脉介入（PCI）已经成为普遍接受的治疗急性ST段抬高型心肌梗死（STEMI）的首选方案。但是,由于人才、技术、设备等条件的限制,急诊PCI仍不能普及或及时。近年来,随着药物的改进和更新,溶栓的治疗效果不断进步,使其成为基层再灌注治疗的一个不可或缺的手段。溶栓治疗实施的越早,其治疗获益就越大。根据实际情况因地制宜的选择合适的溶栓方案及溶栓药物对于改善STEMI患者的预后大有裨益。本文将对现有溶栓药物的特点,及其优劣进行综述,以期获得最合理的利用。     

A randomized evaluation of the effects of glucose-insulin-potassium infusion on myocardial salvage in patients with acute myocardial infarction treated with reperfusion therapy

Background

Intravenous glucose-insulin-potassium (GIK) may have a positive metabolic influence in patients with acute myocardial infarction (AMI) who receive reperfusion therapy. The objective of this randomized trial was to assess for the first time whether GIK improves myocardial salvage in patients with AMI.

Methods

The Reevaluation of Intensified Venous Metabolic Support for Acute Infarct Size Limitation (REVIVAL) trial is a randomized, open-label study conducted among 312 patients with AMI. Patients were randomly assigned to either the GIK therapy group (n = 155) or the control group (n = 157). All patients were intended to receive reperfusion treatment, which was given in all but 5 patients (1.6%). The primary end point of the study was salvage index, measured as the proportion of initial perfusion defect (acute technetium-99m sestamibi scintigraphy) salvaged by therapy (follow-up scintigraphy performed after 7 to 14 days).

Results

The primary end point of the study, the salvage index, was in median 0.50 (25th, 75th percentiles: 0.18, 0.87) in the GIK group and 0.48 (25th, 75th percentiles: 0.27, 0.78) in the control group (P = .96). By 6 months, the mortality rate was 5.8% in the GIK group and 6.4% in the control group (P = .85; relative risk, 0.92; 95% CI, 0.37 to 2.26). Subgroup analyses showed that GIK therapy was associated with increased salvage index only among diabetic patients (mean difference, 0.19; 95% CI, 0.01 to 0.37).

Conclusions

The routine use of GIK therapy in patients with AMI is not associated with enhanced myocardial salvage. This therapy appears to improve myocardial salvage only among diabetic patients.     

Risk assessment in patients with acute myocardial infarction treated with thrombolytic therapy

OBJECTIVE: Several noninvasive methods have prognostic information regarding mortality and new coronary events after an acute myocardial infarction (AMI). The practical for clinical decision-making in the immediate postmyocardial infarction (MI) period is, however, less evident. We investigated consecutive patients with AMI treated with thrombolysis to further clarify this issue. DESIGN: A total of 100 patients (27% women) aged 64 +/- 9 years (mean +/- SD) were studied. Risk assessment based on a clinical score system, myocardial perfusion scintigraphy single photon emission computed tomography (SPECT) at rest and during adenosine stress, echocardiography, radionuclide angiography, symptom-limited exercise stress test, and 24-h Holter ECG recording with ST-analysis and analysis of heart rate variability (HRV) were performed 5-8 days after hospital admission. Mortality, nonfatal reinfarction, and the need for revascularization were followed during 12 months. SETTING: A university hospital. RESULTS: A total of 6 patients died, seven had a nonfatal reinfarction, and 23 were revascularized. Inability to perform an exercise test (P = 0.004) and an ejection fraction (EF) < 40% (P = 0.002) were the only parameters separating those who died from the survivors. No method could predict a nonfatal reinfarction. Patients suffering either death or nonfatal reinfarction had a clinical risk assessment score 2 points higher (8.8 vs. 6.7, P = 0.05) than the group without such events. A positive symptom-limited exercise stress test (P = 0.027), ST-depressions on Holter ECG (P = 0.04), and reversibility on myocardial perfusion scintigraphy (P = 0.029) predicted the need for revascularization. CONCLUSION: Risk assessment based on clinical information, exercise stress testing, and an estimate of left ventricular function (e.g. via echocardiography) contribute with prognostic information in thrombolysed MI-patients. Additional noninvasive investigations such as adenosine-SPECT, analysis of HRV, and Holter-monitoring do not add to these commonly available tools in risk stratification of subjects at low to medium risk.     

Meta-analysis of studies of patients in the United Arab Emirates with ST-elevation myocardial infarction treated with thrombolytic agents

We performed a meta-analysis of 6 studies we conducted in the United Arab Emirates from 1995 to 2009. These included 1,262 patients with ST-elevation myocardial infarction treated with thrombolytic drugs <6 hours after onset of symptoms and signs of myocardial infarction. All patients were treated with tenecteplase or alteplase to induce coronary thrombolysis. Characteristics of patients in all studies were quite similar. Overall mean age was 47 years, 98% were men, 28% had diabetes, 25% were hypertensive, 20% were hyperlipidemic, 56% were smokers, and 9% had sustained previous myocardial infarction. Incidence of adverse outcomes of 30-day mortality (3%), reinfarction (2.5%), stroke (0.4%), or major bleeding (0%) was low compared to global experience with recanalization regardless of how it was induced. There was no incidence of major bleeding requiring transfusion or laparotomy. In conclusion, in predominantly young men in the United Arab Emirates who were admitted and treated early after onset of an acute ST elevation myocardial infarction, recanalization induced by thrombolysis was an attractive therapeutic approach.     

Necropsy evaluation in seven patients with evolving acute myocardial infarction treated with thrombolytic therapy

Systemic and intracoronary streptokinase application may recanalize a coronary artery occluded by a thrombus in patients with acute myocardial infarction (MI). However, thrombolysis fails in a number of patients for unknown reasons. The coronary and myocardial histologic characteristics were studied in 3 patients in whom recanalization was successful without subsequent reocclusion, and in 4 patients in whom recanalization was unsuccessful. All patients died within 4 weeks after the acute intervention. Serial sections from the angiographically localized occlusive site of the infarct vessel, and transverse slices of the heart stained with nitroblue tetrazolium for delineation of MI, were examined by light microscopy. Successfully recanalized arteries were patent at necropsy and showed obstructive fibrous atherosclerotic plaques. Among patients in whom recanalization was unsuccessful, 1 patient had occlusions from nonatherosclerotic intramural hemorrhage and 1 from persisting long, mixed old and fresh thrombus, and 2 patients had high-grade obstructions from ruptured atherosclerotic plaques with intimal hemorrhage and residual clot. Reperfused infarct tissue consisted predominantly of contraction band necroses, whereas MIs without reperfusion showed coagulation necroses of the muscle fibers. The results suggest that the success of recanalization depends, in part, on the morphologic features of the coronary occlusion, and that reperfusion after successful thrombolysis may lead to a different pattern of muscle fiber necrosis in the irreversibly injured infarct areas.     

Effect of glucose-insulin-potassium infusion on plasma free fatty acid concentrations in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction

To determine the effect of glucose-insulin-potassium infusion on circulating levels of free fatty acids in the setting of contemporary management of ST-elevation myocardial infarction, we randomly assigned 20 patients who were undergoing primary angioplasty to glucose-insulin-potassium infusion or to standard care. Treatment with glucose-insulin-potassium was associated with significantly lower levels of free fatty acid after 24 hours compared with standard care.     

溶栓治疗对急性心肌梗死患者运动耐量的影响

目的 :探讨溶栓治疗对急性心肌梗死 (AMI)患者急性期和远期运动耐量的影响。方法 :将 143例 AMI患者分为溶栓再通组 (35例 )、未通组 (2 3例 )和非溶栓组 (85例 ) ,比较三组急性期和远期运动耐量。结果 :急性期 ,再通组的运动量、运动时间、最大心率、心率血压乘积均明显高于未通组和非溶栓组 (P<0 .0 5 ) ,运动诱发的心绞痛或血压下降≥ 10 m m Hg(1m m Hg=0 .133k Pa)的比率明显低于后两者 (P <0 .0 5 )。远期随访 ,三组的运动量、最大心率、运动时间、心率血压乘积及运动诱发心绞痛或血压下降的比率均无显著性差异 (P >0 .0 5 )。结论 :溶栓再通能显著提高 AMI患者急性期运动耐量 ,但对远期运动耐量改善不明显     

Explanation for the survival benefit of primary angioplasty over thrombolytic therapy in patients with ST-elevation acute myocardial infarction

Our study evaluated the interaction across mortality risk, time delay related to percutaneous coronary intervention (PCI), and survival benefit of PCI over thrombolytic therapy (risk-time benefit analysis). Mortality risk and angioplasty-related time delay were independently correlated to 30-day survival benefit of primary angioplasty over lytic therapy. A PCI-related delay>60 minutes could be justified for high-risk patients.     

静脉溶栓治疗老年急性心肌梗死的临床分析

目的 探讨老年(≥75岁)急性心肌梗死患者静脉溶栓的疗效及安全性. 方法 将62例老年急性心肌梗死患者随机分为溶栓组和常规治疗组;溶栓组32例,采用尿激酶静脉溶栓加皮下注射小剂量低分子肝素钙.常规治疗组30例.除不用尿激酶及小剂量低分子肝素钙外,其余治疗均与溶栓组相同.结果 冠状动脉再通率溶栓组为65.6%(21/32),常规治疗组为16.7%(5/30),两组比较差异具有显著性(P<0.05);溶栓组病死率6.3%(2/32),而常规治疗组病死率为23.3%(7/30),两组比较具有显著差异性(P<0.05);两组无严重出血并发症,出血并发症比较差异无显著性(P>0.05). 结论 尿激酶静脉溶栓治疗老年急性心肌梗死可以提高冠状动脉再通率,降低死亡率和改善预后,是可行性治疗措施.     

Selection of patients with acute myocardial infarction for thrombolytic therapy

PURPOSE: To critically review the current recommendations regarding the eligibility of patients with myocardial infarction for thrombolytic therapy. DATA IDENTIFICATION: Relevant studies published from January 1980 to January 1990 were identified through a computerized search of the English-language literature using MEDLINE and by a manual search of the bibliographies of all identified articles. STUDY SELECTION: All randomized, controlled trials of intravenous thrombolysis in acute myocardial infarction and unstable angina were reviewed. Smaller, observational studies and previous review articles were included when relevant to the discussion. DATA EXTRACTION: Key data were extracted from each article, including the proportions of patients eligible for thrombolysis, the reasons for exclusion from thrombolytic therapy, and the clinical outcomes of patients treated and of those excluded from treatment. The validity of certain exclusion criteria was examined using subgroup analysis from the large, randomized mortality trials of intravenous thrombolysis and observations from smaller, nonrandomized studies. RESULTS OF DATA SYNTHESIS: To date, relatively few patients with myocardial infarction have been considered eligible for fibrinolytic therapy. In this group, both early and late mortality have been significantly reduced. Patients excluded from thrombolysis, however, continue to have a high early mortality. The data suggest that the potential benefits of this treatment might be extended to selected high-risk subgroups. In particular, the risk-benefit ratio may favor the inclusion of otherwise healthy elderly patients; certain patients presenting more than 6 hours after the onset of symptoms; and patients with a history of controlled systolic hypertension or brief, nontraumatic cardiopulmonary resuscitation. The data do not support the use of fibrinolytic therapy as primary treatment in patients with unstable angina or suspected myocardial infarction in the absence of confirmatory electrocardiographic changes. CONCLUSIONS: The full potential of thrombolytic therapy to alter the natural history of acute myocardial infarction can only be realized through the continued evaluation of selection criteria and the identification and treatment of the greatest possible number of eligible patients.     

院前静脉溶栓治疗急性心肌梗死的临床随机对照研究

目的　评价重组组织型纤溶酶原激活剂 (rt PA)在院前救治急性心肌梗死 (AMI)的近期临床治疗效果 ,并探讨在院前对AMI患者进行静脉溶栓治疗的安全性和可行性。方法　对所收治的AMI患者进行分组 ,均给予rt PA( 5 0mg)进行静脉溶栓治疗 ,对比两者的冠状动脉再通率以及发病至溶栓时间延迟对rt PA静脉溶栓疗效的影响。结果　从患者发病至进行溶栓治疗的时间间隔 ,院前组平均比院内组缩短 2 .2小时 [( 2 .9± 1.4)小时比 ( 5 .1± 1.1)小时 ] ,P <0 .0 5 ;院前治疗组的冠状动脉总再通率为 90 % ,明显高于院内治疗组的 61.8% (P <0 .0 5 )。结论　院前应用rt PA( 5 0mg)进行静脉溶栓治疗安全、可行。     

溶栓治疗老年人急性心肌梗死34例分析

目的观察老年人急性心肌梗死（ＡＭＩ）溶栓治疗的安全性和有效性。方法７１例７０岁以上老年ＡＭＩ患者分成溶栓组（３４例）和对照组（３７例），比较其临床结果。结果（１）梗死相关动脉（ＩＲＡ）的再通率溶栓组显著高于对照组（６１．８％及１３．５％，Ｐ＜０．０１）；（２）溶栓明显改善了老年ＡＭＩ患者的左室射血分数（６３％及５２％，Ｐ＜０．０５）；（３）溶栓显著降低了老年ＡＭＩ患者的住院病死率（３５．１％对１４．７％，Ｐ＜０．０５），降幅为２０．４％；（４）溶栓组发生出血并发症６例（皮肤淤斑４例，上消化道出血２例），无严重出血（无需输血）并发症及脑卒中发生。结论对无禁忌证的老年人ＡＭＩ进行溶栓治疗，可以增加其血管再通率、改善心功能及降低病死率。     

Diabetes mellitus is a strong negative prognostic factor in patients with myocardial infarction treated with thrombolytic therapy

OBJECTIVES: To assess the long-term prognostic values of baseline demographic data, occurrence of vectorcardiographic signs of reperfusion, left ventricular function and coronary angiographic features. DESIGN: Longitudinal study of morbidity and mortality. SETTING: Coronary care unit at Danderyd Hospital, Stockholm, Sweden. SUBJECTS: A total of 222 patients (mean age 61 years) with a suspected acute myocardial infarction treated with thrombolysis were investigated and followed for 2-5 years (mean 1216 days). MAIN OUTCOME MEASURES: Death or a new myocardial infarction. RESULTS: Age above 55 years (P < 0.05), a previous diagnosis of diabetes mellitus (P < 0.005), hypertension (P < 0.05), heart failure (P < 0.001) and myocardial infarction (P < 0.05), a previous use of beta-blockers (P < 0.05) and an ejection fraction below 60% (P < 0.01) were predictors for death or a new myocardial infarction in univariate analysis. Sex, a previous history of smoking or angina pectoris, vectorcardiographic signs of reperfusion or degree of coronary artery disease had no prognostic values. In multivariate analysis including age above 55 years, a previous diagnosis of diabetes mellitus, hypertension and myocardial infarction, and an ejection fraction below 60%, only age (P < 0.05), diabetes mellitus (P < 0. 01) and ejection fraction (P < 0.05) were predictors for death or a new myocardial infarction. CONCLUSIONS: The results of the present study emphasize the importance of diabetes mellitus as a long-term prognostic risk factor in patients with myocardial infarction treated with thrombolysis. Further studies are needed to determine the mechanisms behind this increased risk.