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1.

Background

Glutamate plays a key role for post-ischaemic recovery of myocardial metabolism. According to post hoc analyses of the two GLUTAMICS trials, patients without diabetes benefit from glutamate with less myocardial dysfunction after coronary artery bypass surgery (CABG). Copeptin reflects activation of the Arginine Vasopressin system and is a reliable marker of heart failure but available studies in cardiac surgery are limited. We investigated whether glutamate infusion is associated with reduced postoperative rises of plasma Copeptin (p-Copeptin) after CABG.

Methods

A prespecified randomised double-blind substudy of GLUTAMICS II. Patients had left ventricular ejection fraction ≤0.30 or EuroSCORE II ≥3.0 and underwent CABG ± valve procedure. Intravenous infusion of 0.125 M L-glutamic acid or saline at 1.65 mL/kg/h was commenced 10–20 min before the release of the aortic cross-clamp and then continued for another 150 min P-Copeptin was measured preoperatively and postoperatively on day one (POD1) and day three. The primary endpoint was an increase in p-Copeptin from the preoperative level to POD1. Postoperative stroke ≤24 h and mortality ≤30 days were safety outcomes.

Results

We included 181 patients of whom 48% had diabetes. The incidence of postoperative mortality ≤30 days (0% vs. 2.1%; p = .50) and stroke ≤24 h (0% vs. 3.2%; p = .25) did not differ between the glutamate group and controls. P-Copeptin increased postoperatively with the highest values recorded on POD1 without significant inter-group differences. Among patients without diabetes, p-Copeptin did not differ preoperatively but postoperative rise from preoperative level to POD1 was significantly reduced in the glutamate group (73 ± 66 vs. 115 ± 102 pmol/L; p = .02). P-Copeptin was significantly lower in the Glutamate group on POD1 (p = .02) and POD 3 (p = .02).

Conclusions

Glutamate did not reduce rises of p-Copeptin significantly after moderate to high-risk CABG. However, glutamate was associated with reduced rises of p-Copeptin among patients without diabetes. These results agree with previous observations suggesting that glutamate mitigates myocardial dysfunction after CABG in patients without diabetes. Given the exploratory nature of these findings, they need to be confirmed in future studies.  相似文献   
2.
Myocardial injury due to ischaemia within 30 days of non-cardiac surgery is prognostically relevant. We aimed to determine the discrimination, calibration, accuracy, sensitivity and specificity of single-layer and multiple-layer neural networks for myocardial injury and death within 30 postoperative days. We analysed data from 24,589 participants in the Vascular Events in Non-cardiac Surgery Patients Cohort Evaluation study. Validation was performed on a randomly selected subset of the study population. Discrimination for myocardial injury by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.70 (0.69–0.72) vs. 0.71 (0.70–0.73) with variables available before surgical referral, p < 0.001; 0.73 (0.72–0.75) vs. 0.75 (0.74–0.76) with additional variables available on admission, but before surgery, p < 0.001; and 0.76 (0.75–0.77) vs. 0.77 (0.76–0.78) with the addition of subsequent variables, p < 0.001. Discrimination for death by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.71 (0.66–0.76) vs. 0.74 (0.71–0.77) with variables available before surgical referral, p = 0.04; 0.78 (0.73–0.82) vs. 0.83 (0.79–0.86) with additional variables available on admission but before surgery, p = 0.01; and 0.87 (0.83–0.89) vs. 0.87 (0.85–0.90) with the addition of subsequent variables, p = 0.52. The accuracy of the multiple-layer model for myocardial injury and death with all variables was 70% and 89%, respectively.  相似文献   
3.
Background and aimsThe relationship between hemoglobin glycation index (HGI) and the diagnosis and prognosis of cardiovascular disease (CVD) has been verified by previous studies. However, it remains unknown whether HGI has a predictive effect on subclinical myocardial injury (SC–MI). The purpose of the present study was to explore the relationship between HGI and SC–MI in the general population free from CVD.Methods and resultsThe present study included 6009 participants free of CVD from the third National Health and Nutrition Examination Survey. Binary Logistic regression analysis was used to tested the association between HGI and SC–MI. As results, the HGI was significantly higher in participants with SC–MI compared with those without, and the HGI was positively correlated with SC–MI and other metabolic disorder parameters. Each 1-unit increase of HGI and glycated hemoglobin A1c (HbA1c) was independently associated with higher risk of SC–MI (P < 0.05), while fasting plasma glucose (FPG) was no longer a predictive indicator of SC–MI with the increase of confounding factors [OR (95% CI): 1.001 (0.999–1.003), P = 0.305]. And in the subgroup analysis, HGI, only in participants without diabetes, was independently associated with higher risk of SC–MI, while HbA1c and FPG had no independent predictive role in both diabetic and non-diabetic participants.ConclusionsHGI was a significant predictor of SC–MI in the general population free from CVD.  相似文献   
4.
Background and aimsHyperuricemia is widely thought as a risk factor for myocardial infarction (MI) and all-cause mortality; however, the relation of serum uric acid (sUA) and subclinical myocardial injury (SCeMI) remains unclear. We hypothesize that sUA is associated with subclinical myocardial injury.Methods and resultsA total of 5880 adult individuals (57.9 ± 13.0 years, 54.23% women) without known cardiovascular disease from National Health and Nutrition Examination Survey (NHANES) III were included. Determined by Cardiac Infarction Injury Score (CIIS) from 12-lead electrocardiogram, SCeMI was defined by CIIS ≥10 units. The relationship between sUA and SCeMI was analyzed by using logistic regression models and the smooth curve fitting. Subgroup analyses were conducted. After adjusting for potential confounding variables, the smooth curve fitting revealed a non-linear relationship between sUA level and SCeMI. When sUA was above the inflection point 266.5 μmol/L, each 100 unit increase in sUA increase the risk of SCeMI by 15%. In women group, when sUA>340.3 μmol/L, each 100 unit increase in sUA increase the risk of SCeMI by 71%, but no significant correlation was observed in men group.ConclusionsOur findings confirm that sUA is an independent risk factor for subclinical myocardial injury after adjusting for potential confounding variables, and existence of such an association in women only, which require more random control trials to confirm the strategy of cardiovascular disease prevention based on sUA reduction in female.  相似文献   
5.
Elevated serum uric acid (SUA) levels have been associated with several cardiovascular risk factors and the progression of coronary artery disease. In the setting of acute myocardial infarction, increasing evidence suggests that high SUA levels could be related to adverse outcomes. Interestingly elevated SUA levels have been linked to endothelial dysfunction, inflammation and oxidative stress. The aim of this review is to discuss the potential negative effects of SUA in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, analyzing the possible underlying pathophysiological mechanisms.  相似文献   
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8.
目的 评价新型心脏专用机D-SPECT在体外心脏震波治疗经皮冠状动脉介入术( percutaneous coronary intervention, PCI)患者前后血流灌注及心功能的影响.方法 在同济大学附属第十人民医院行PCI术后接受体外心脏震波治疗的患者30例,男22例,女8例,分别在 PCI术后3个月行体外心脏震波治疗( cardiac shock wave therapy, CSWT)前接受D-SPECT一日法腺苷负荷心肌灌注检查,CSWT治疗后6~9个月再次接受D-SPECT一日法腺苷负荷心肌灌注检查,使用定量灌注 SPECT ( quantitative perfusion SPECT, QPS )和定量门控 SPECT (quantitative gated SPECT, QGS)图像处理软件,分析比较心肌17节段分布下体外心脏震波治疗前后静息/负荷状态下左心室射血分数(left ventricular enjection fraction, LVEF)%、总负荷评分(sunned stress score, SSS)、总静息评分(summed rest score, SRS)、静息/负荷舒张末容积(end diastolic volume, EDV)、静息/负荷收缩末容积( end systolic volume, ESV)以及了解治疗前后静息/负荷状态下心肌缺损程度总评分、心肌缺损节段数的变化情况及典型图片分析.结果 静息及负荷状态下心肌缺血节段数治疗后较治疗前均明显减少(P<0. 05);静息和负荷状态下心肌各节段灌注总评分治疗后较治疗前明显减低(P<0. 05);心功能检测指标: 静息/负荷状态下LVEF(%)治疗后较治疗前提高(P<0. 05);静息/负荷状态下EDV、ESV较治疗后明显改善( P<0. 05);典型图片提示治疗后心肌缺血面积明显缩小.结论 D-SPECT心肌核素灌注显像可以很好的评价心肌血流灌注及心功能的情况,临床应用前景广阔.体外心脏震波对PCI术后患者心肌功能的恢复有明显的改善作用,是一项无创、安全、有效的辅助治疗手段.  相似文献   
9.
杨军 《当代医学》2022,28(7):4-6
目的观察分析急性心肌梗死患者早期嚼服氯吡格雷与阿司匹林联合静脉溶栓治疗的临床效果。方法选取2019年11月至2020年11月本院收治的100例急性心肌梗死患者作为研究对象,随机分为常规组(嚼服阿司匹林治疗)和研究组(嚼服氯吡格雷及阿司匹林治疗),各50例。比较两组临床疗效、左室射血分数、急性生理与慢性健康评分(APACHEⅡ)及出血不良反应情况。结果研究组治疗总有效率高于常规组(P<0.05);研究组左室射血分数高于常规组,APACHEⅡ评分低于常规组(P<0.05);两组出血不良反应发生率比较差异无统计学意义。结论急性心肌梗死患者静脉溶栓治疗后嚼服氯吡格雷与阿司匹林,可进一步提高临床疗效,改善患者心功能,且安全性较高,出血不良反应少,值得临床推广应用。  相似文献   
10.
邓容  李广权  苟甜甜  张林  陈欢 《西部医学》2022,34(7):1056-1060
目的 探讨血清D-二聚体(D-D)、纤维蛋白原(Fib)检测联合血栓弹力图(TEG)对急性心肌梗死(AMI)预后的评估价值。方法 选取2018年8月~2021年2月我院收治的AMI患者126例,所有患者均接受经皮冠状动脉介入(PCI)治疗,根据患者随访期间是否发生主要心血管不良事件(MACE)将患者分为预后不良组(n=41)和预后良好组(n=85)。比较两组患者的一般临床资料、血清D-D、Fib和TEG指标,分析D-D、Fib和TEG指标的相关性,采用受试者工作特征曲线(ROC)分析D-D、Fib和TEG指标对AMI患者预后的评估价值。结果 预后不良组患者的收缩压(SBP)、舒张压(DBP)水平明显小于预后良好组,心率(HR)明显高于预后良好组(均P<0.05);预后不良组患者的血清D-D、Fib水平高于预后良好组,两组患者的TEG指标凝血反应时间(R)、凝血形成速率(Angle角)、血栓最大振幅值(MA)和凝血综合指数(CI)比较,差异有统计学意义(均P<0.05)。Logistic回归分析结果显示,血清D-D、Fib、R、Angle角、MA和CI是影响患者预后的独立危险因素(P<0.05);相关性分析结果显示,D-D与R呈负相关,与Angle角、MA值和CI均呈正相关(P<0.05);Fib与MA值、CI呈正相关(P<0.05)。ROC曲线分析结果显示,D-D、Fib、R、Angle角、MA值和CI评估AMI患者预后的AUC值分别为0.838、0.824、0.791、0.780、0.808、0.677,联合检测的AUC值为0.863,对AMI患者预后的评估有统计学意义(均P<0.05)。结论 血清D-D、Fib和TEG指标的变化与AMI患者PCI术后MACE发生存在相关性,对AMI患者预后不良的评估具有一定临床价值。  相似文献   
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