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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   
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ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established.  相似文献   
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ObjectiveDeterioration of the native aortic valve function by a late progression of rheumatic disease is not infrequent in patients who underwent rheumatic mitral valve surgery; however, this phenomenon has not been clearly quantified.MethodsA total of 1155 consecutive patients (age 52.0 ± 12.9 years; 807 female) who underwent rheumatic mitral valve surgery without concomitant aortic valve surgery from 1997 to 2015 were enrolled. The primary end point was the composite of progression to severe aortic valve dysfunction or a requirement of subsequent aortic valve replacements during follow-up. To determine the risk factors of the primary outcome, we performed the generalized linear mixed model.ResultsThe baseline severities of aortic valve were none to trivial in 880 patients (76.2%), mild in 256 patients (22.2%), and moderate in 19 patients (1.6%). The latest 1062 echocardiographic assessments (91.9%; median, 81.2 postoperative months; interquartile range, 37.3-132.1 months) demonstrated 26 cases (0.33%/patient-year) meeting the primary end point during follow-up. Cumulative incidence of the primary end point at 10 years was 0.4% ± 0.3% and 7.4% ± 2.5% depending on the presence of mild or greater aortic valve dysfunction at baseline (P < .01). In multivariable analyses, aortic valve peak pressure gradient (odds ratio, 1.14; 95% confidence interval, 1.10-1.20), aortic regurgitation degree (mild over none: odds ratio, 3.26; 95% confidence interval, 1.15-9.23), and time (odds ratio, 1.30; 95% confidence interval 1.19-1.41) were significantly associated with the occurrence of the primary end point.ConclusionsProgression of severe aortic valve dysfunction and the need for aortic valve replacement are uncommon in patients undergoing rheumatic mitral valve surgery. However, such events were relatively common among those with mild or greater aortic valve dysfunction at the time of mitral valve surgery.  相似文献   
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目的研究腹腔镜经脐单一部位幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄的临床效果。方法100例小儿先天性肥厚性幽门狭窄患儿作为研究对象,按照随机方式分为观察组和对照组,每组50例。对照组采用腹腔镜幽门环肌切开术治疗,观察组采用腹腔镜经脐单一部位幽门环肌切开术治疗。观察记录患儿的手术结果及随访结果,并比较两组患儿手术时间、术后住院时间。结果手术过程顺利,100例患儿均成功完成手术,无一例中转开腹手术,无并发症发生。观察组患儿术后6 h将胃管取下,少量喂入温水后逐渐过渡到喂糖水、喂奶;对照组患儿术后24 h开始逐渐进食。患儿术后进行6个月的延续性随访,观察组患儿切口恢复美观,已经无法观察到切口瘢痕,两组患儿的生长发育均显示正常状态。观察组患儿手术时间(21.23±1.65)min及术后住院时间(5.58±1.98)d均显著短于对照组的(38.44±1.23)min、(9.67±1.22)d,差异具有统计学意义(P<0.05)。结论先天性肥厚性幽门狭窄患儿采用腹腔镜经脐单一部位幽门环肌切开术治疗,手术效果良好,手术创伤小而且安全。  相似文献   
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目的探讨微创后路腰椎椎间融合术(MIS-PLIF)和传统开放PLIF对腰椎退行性疾病(LDD)远期疗效及安全性的影响。方法 2011年1月-2014年12月收治LDD患者182例,其中96例采用传统开放PLIF治疗(PLIF组),86例采用MIS-PLIF治疗(MIS-PLIF组)。比较2组腰椎矢状位参数、多裂肌横截面积及萎缩率、融合率、疼痛视觉模拟量表(VAS)评分、日本骨科学会(JOA)评分、Oswestry功能障碍指数(ODI)及术后并发症发生情况,分析多裂肌萎缩率与顽固性腰背痛的相关性。结果 2组术后各随访时间点椎间隙高度恢复值和节段性前凸角恢复值差异均无统计学意义(P > 0.05)。2组术后1年腰椎前凸角恢复值差异无统计学意义(P > 0.05);但术后5年和末次随访时,MIS-PLIF组腰椎前凸角恢复值显著高于PLIF组,差异均有统计学意义(P < 0.05)。MIS-PLIF组术后各随访时间点多裂肌横截面积大于PLIF组,多裂肌萎缩率低于PLIF组,差异均有统计学意义(P < 0.05)。2组术后随访6个月融合率差异无统计学意义(P > 0.05)。2组术后各随访时间点下肢痛VAS评分差异无统计学意义(P > 0.05);MIS-PLIF组术后各随访时间点腰痛VAS评分、JOA评分及ODI均优于PLIF组,差异有统计学意义(P < 0.05)。MIS-PLIF组顽固性腰背痛发生率显著低于PLIF组,差异有统计学意义(P < 0.05)。合并顽固性腰背痛患者多裂肌萎缩率高于未合并顽固性腰背痛的患者,差异有统计学意义(P < 0.05)。结论术后多裂肌萎缩可能是导致顽固性腰背痛的重要原因,相较于传统开放PLIF,MIS-PLIF治疗LDD能够更有效地保持腰椎生理曲度,改善肢体活动功能,降低多裂肌萎缩程度,有助于避免顽固性腰背痛的发生。  相似文献   
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