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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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BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.  相似文献   
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BackgroundDiabetes mellitus is a major risk factor for coronary artery disease (CAD) and may provoke structural and functional changes in coronary vasculature. The coronary volume to left ventricular mass (V/M) ratio is a new anatomical parameter capable of revealing a potential physiological imbalance between coronary vasculature and myocardial mass. The aim of this study was to examine the V/M derived from coronary computed tomography angiography (CCTA) in patients with diabetes.MethodsPatients with clinically suspected CAD enrolled in the ADVANCE (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care) registry and known diabetic status were included. Coronary artery volume and left ventricular myocardial mass were analyzed from CCTA and the V/M ratio was calculated and compared between patients with and without diabetes.ResultsOf the 3053 patients (age 66 ?± ?10 years; 66% male) with known diabetic status, diabetes was present in 21.9%. Coronary volume was lower in patients with diabetes compared to those without diabetes (2850 ?± ?940 ?mm3 vs. 3040 ?± ?970 ?mm3, p ?< ?0.0001), whereas the myocardial mass was comparable between the 2 groups (122 ?± ?33 ?g vs. 122 ?± ?32 ?g, p ?= ?0.70). The V/M ratio was significantly lower in patients with diabetes (23.9 ?± ?6.8 ?mm3/g vs. 25.7 ?± ?7.5 ?mm3/g, p ?< ?0.0001). Among subjects with obstructive CAD (n ?= ?2191, 24.0% diabetics) and non-obstructive CAD (16.7% diabetics), the V/M ratio was significantly lower in patients with diabetes compared to those without (23.4 ?± ?6.7 ?mm3/g vs. 25.0 ?± ?7.3 ?mm3/g, p ?< ?0.0001 and 25.6 ?± ?6.9 ?mm3/g vs. 27.3 ?± ?7.6 ?mm3/g, respectively, p ?= ?0.006).ConclusionThe V/M ratio was significantly lower in patients with diabetes compared to non-diabetics, even after correcting for obstructive coronary stenosis. The clinical value of the reduced V/M ratio in diabetic patients needs further investigation.  相似文献   
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目的 探讨中性粒细胞-淋巴细胞计数比率 (NLR)、白蛋白-球蛋白比率(AGR)与食管鳞状细胞癌(ESCC)患者总 生存(OS)期的关系,评估两项指标联合对预测 ESCC 患者预后的应用价值。 方法 本研究回顾性分析了自 2015 年 01 月至 2019 年 12 月间于南通大学附属如皋医院首诊并接受手术治疗的 144 例 ESCC 患者的血常规、血生化检测结果与随访数据。 通过受试者操作特征(ROC)曲线确定 NLR、AGR 的最佳临界值,利用曲线下面积(AUC)评估各指标对 ESCC 患者 OS 期的预 测效能。 通过 Kaplan-Meier 曲线及 Cox 单、多变量回归分析评估两种预测指标的预后价值。 结果 根据期曲线,NLR 与 AGR 预测 ESCC 患者 OS 期的最佳截断值分别为 1. 45 和 1. 48, AUC 值分别为 0. 713 (95%CI = 0. 628 ~ 0. 797)和 0. 673 (95%CI = 0. 584~ 0. 761)。 Kaplan-Meier 曲线展示高 NLR( >1. 45)与低 NLR(≤1. 45)组患者的中位 OS 期分别为 51. 8 个月(95%CI = 36. 2~ 67. 3)和 20. 1 个月(95%CI = 14. 1~ 26. 2),差异有统计学意义(χ 2 = 20. 474, P<0. 001)。 术前低 AGR 值( <1. 48)与 ESCC 患者不良预后显著相关[中位 OS 期:22. 5 个月 (95%CI = 15. 1 ~ 29. 9)比 43. 3 个月 (95%CI = 25. 7 ~ 60. 8)],差异有统计 学意义 (χ 2 = 6. 749, P= 0. 009)。 单、多变量 Cox 分析证实淋巴结转移(HR = 3. 626, 95%CI = 2. 152 ~ 6. 110,P<0. 001)、NLR (HR= 1. 960, 95%CI = 1. 198~ 3. 207,P= 0. 007)与 AGR (HR= 1. 791, 95%CI = 1. 099 ~ 2. 920,P = 0. 019)是 ESCC 患者的独立 预后因素。 此外,我们发现 NLR 联合 AGR 评分(0 分:NLR≤1. 45 且 AGR≥1. 48;1 分: NLR>1. 45 或 AGR<1. 48;2 分:NLR> 1. 45 且 AGR<1. 48 )能够进一步分层 ESCC 患者的预后,患者评分越高,预后越差。 0 分、1 分与 2 分患者的中位 OS 期分别为 56. 6 个月(95%CI = 40. 2~ 67. 3)、29. 9 个月(95%CI = 20. 1~ 39. 8)和 18. 2 个月(95%CI = 12. 1~ 24. 3),组间差异有统计学意义 (0 分比 1 分: χ 2 = 6. 795, P= 0. 009;0 分比 2 分: χ 2 = 19. 529, P<0. 001;1 分比 2 分: χ 2 = 7. 011, P = 0. 008)。 结论 NLR 与 AGR 是评估 ESCC 患者预后的敏感指标,两者联合可以更有效地识别预后不良患者,进而提供更为详尽的预后分层。  相似文献   
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ObjectiveTo determine the long-term cardiovascular disease risk of astronauts with spaceflight exposure compared with a well-matched cohort.MethodsNational Aeronautics and Space Administration (NASA) astronauts are selected into their profession based upon education, unique skills, and health and are exposed to cardiovascular disease risk factors during spaceflight. The Cooper Center Longitudinal Study (CCLS) is a generally healthy cohort from a preventive medicine clinic in Dallas, Texas. Using a matched cohort design, astronauts who were selected beginning April 1, 1959, (and each subsequent selection class through 2009) and exposed to spaceflight were matched to CCLS participants who met astronaut selection criteria; 1514 CCLS participants matched to 303 astronauts in a 5-to-1 ratio on sex, date of birth, and age. The outcome of cardiovascular mortality through December 31, 2016, was determined by death certificate or National Death Index.ResultsThere were 11 deaths caused by cardiovascular disease (CVD) among astronauts and 46 among CCLS participants. There was no evidence of increased mortality risk in astronauts (hazard ratio [HR]=1.10; 95% confidence interval [CI], 0.50 to 2.45) with adjustment for baseline cardiovascular covariates. However, the secondary outcome of CVD events showed an increased adjusted risk in astronauts (HR=2.41; 95% CI, 1.26 to 4.63).ConclusionNo increased risk of CVD mortality was observed in astronauts with spaceflight exposure compared with a well-matched cohort, but there was evidence of increased total CVD events. Given that the duration of spaceflight will increase, particularly on missions to Mars, continued surveillance and mitigation of CVD risk is needed to ensure the safety of those who venture into space.  相似文献   
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