递增负荷运动对心电频谱分析的影响

为了了解递增负荷运动对心电频谱分析的影响,我们采用标准12导联引导心电信号,测试了30名大学生在递增负荷运动中的心电频谱图,所测得结果提示如下:频率成分能量比W1〔W1=E(100-1000Hz)/E(0-1000Hz)〕,W2〔W2=E(80-300Hz)/E(0-1000Hz)〕,在一、二级负荷运动后增大(P＜0.05),三级负荷后恢复到安静水平。     

Exploratory insights from the right-sided electrocardiogram following prolonged endurance exercise

Background: Prolonged strenuous exercise has a profound effect on cardiac function. The right heart may be more susceptible to this imposition; yet, right-sided chest leads have not been utilised in this setting. Methods: Thirty highly trained athletes at the 2014 Western States 100-mile Endurance Run from Squaw Valley to Auburn, California (body mass 68?±?12?kg, age 45?±?10?years, 57?±?15?miles per week) were recruited for the study. Pre- and post-race, a right-sided 12-lead ECG was obtained and data were extracted for P, R and S waves, J point, ST segment and T wave amplitude. Data were compared using Students T-test and statistical significance set as P?Results: There was a significant increase in P wave amplitude (29%) and QTc interval (4%) pre- to post-race from standard 12-lead ECG. From the right-sided12-lead ECG, a 23% (P?=?.01) and 38% (P?=?.03) increase in J point amplitude in V1R and V2R and a 22% (P?=?.05) increase in ST segment integral in V2R and V3R were evident. T wave inversion was evident in leads V2R–V6R in 50–90% of athletes, respectively. Close examination revealed marked heterogeneity in individual ECGs. Conclusions: Completion of a 100-mile ultra-marathon resulted in significant changes in the right-sided ECG alongside more marked responses in specific individuals. P wave, ST segment and T wave changes post-race are indicative of acute exercise-induced right heart electrical adaptation.     

学习元宇宙之内涵、机理、架构与应用研究——兼及虚拟化身的学习促进效果

进入万物互联时代,学习必然是多维度、具身式、智能化的过程,数字化全域感知的交互式环境,正有力地促进着学习者高阶思维的发展。学习元宇宙(Metaverse for learning)是在元宇宙虚实融合一体化理念之基础上,面向学习者所营造的、多技术集成的沉浸式学习环境。学习元宇宙聚焦学习主体,关注在元宇宙场域中沉浸式环境的设计、交互式学习方式呈现和学习效果的评价,其研究主要在“环境”“方式”“效果”三方面展开。学习元宇宙的机理体现在“共同在场”“心流状态”“虚拟化身”,其主要特点在于学习过程的沉浸性、化身性、特殊性;同时,学习元宇宙具有“技术端、应用端、分析端”三端六层架构。为验证学习元宇宙中虚拟化身的学习成效,基于Minecraft和Roblox两种学习元宇宙形态,对67名被试者在体验三类拟真场景中的数据进行采集与分析,得到了在不同环境中“共同在场”“心流状态”“虚拟化身”三项体现学习元宇宙机理的指标表现。进而,引入心理生理分析技术,对学习者的心电数据(ECG)进行测试,发现在学习元宇宙中的“虚拟化身”能表征出促进学习效果的生理证据。研究结果表明:两种学习元宇宙形态对学习成效都有较好的表现。这为未来虚拟学习场景中的数字化身、虚拟人学习状态分析的设计与教学开展,提供了一定的理论依据与借鉴价值。     

运动前心血管筛查的国际经验与启示

运用文献资料和逻辑分析的方法,系统梳理和总结运动前心血管筛查领域的国际经验,并结合本土研究和国情为我国运动前心血管筛查方案的设计和运动猝死预防体系的建立提供参考。运动前心血管筛查一般通过家族史、个人病史、体格检查和安静心电图对运动员或锻炼者的心源性猝死风险进行评估,从而筛查高风险个体,并采取相应措施降低风险,是运动猝死一级预防的国际主流方法。尽管对筛查方案的一些细节仍有争议,但2017年各国学者联合发布的运动员心电图解读国际标准专家共识大幅提升了安静心电图筛查的敏感性和特异性,纳入安静心电图的运动前心血管筛查方案逐渐被世界许多国家和各大国际体育组织所接受。建议通过制订运动猝死登记制度,建立系统的运动前心血管筛查体系和方法,加强新兴安全筛查方法和技术研究,从而改进我国的运动前心血管筛查工作。     

Early association of electrocardiogram alteration with infarct size and cardiac function after myocardial infarction

Objective: Myocardial infarction (MI) is the main cause of heart failure, but the relationship between the extent of MI and cardiac function has not been clearly determined. The present study was undertaken to investigate early changes in the electrocardiogram associated with infarct size and cardiac function after MI. Methods: MI was induced by ligating the left anterior descending coronary artery in rats. Electrocardiograms, echocardiographs and hemodynamic parameters were assessed and myocardial infarct size was measured from mid-transverse sections stained with Masson's trichrome. Results: The sum of pathological Q wave amplitudes was strongly correlated with myocardial infarct size (r = 0.920, P < 0.0001), left ventricular ejection fraction (r = (0.868, P < 0.0001) and left ventricular end diastolic pressure (r = 0.835, P < 0.0004). Furthermore, there was close relationship between MI size and cardiac function as assessed by left ventricular ejection fraction (r = (0.913, P < 0.0001) and left ventricular end diastolic pressure (r = 0.893, P < 0.0001). Conclusion: The sum of pathological Q wave amplitudes after MI can be used to estimate the extent of MI as well as cardiac function.     

基于人体心房模型的房间阻滞仿真（英文）

目的:探究不同心房间传导通道阻滞的组合对形成房间阻滞的影响及体表心电图变化,探究房间阻滞的产生机理。创新点:通过仿真证明了单一Bachmann束阻滞并不能产生典型的房间阻滞P波时长和波形,并结合电兴奋传导时序,解释了房间阻滞的产生机理。方法:通过64位螺旋电子计算机断层扫描(CT)扫描人体心房,构建心房解剖模型。阻断不同的心房间传导通道,以单域方程仿真出心房电兴奋传导时序,采用边界元法计算各时刻人体体表电位,进而计算出P波波形。结论:要使P波时长和形态均满足临床诊断房间阻滞的条件,必须同时阻断Bachmann束和右肺静脉后部的穿间隔纤维(VRPV)通道,这为进一步了解房间阻滞的发病机制及未来临床研究提供了指导。     

驾驶员疲劳状态下心电图指标动态监测研究

疲劳驾驶是引起交通事故的重要原因之一,为预防驾驶疲劳,国内外科学家研究了多种监测驾驶疲劳的方法,其中采用心电图指标监测驾驶疲劳具有实用价值。采集6名实验对象90分钟模拟驾驶操作的心电信号,并对所选取的8个心电图指标进行分析,通过分析实验数据显示：LF、HF、LF/HF、LFNU和HFNU五个指标随着驾驶时间的增长发生显著性变化,且伴有明显波动;LF、HF和LF/HF三个指标的变化能够反映驾驶员的疲劳状态,其中LF/HF指标变化适时反映了驾驶员疲劳产生特性。因此,采用心电图指标可以对驾驶员疲劳状态进行动态监测。     

The effects of dehydration and rehydration on electrocardiographic and echocardiographic parameters in Greco-Roman wrestlers

Abstract

The effects of exercise training on heart have been widely explored. However, less understood are the effects of dehydration and rehydration on electrocardiographic (ECG) and echocardiographic (Echo) parameters in wrestlers. The aim of this study was to determine the effect of dehydration and rehydration on some ECG and Echo parameters. Fourteen healthy high school wrestlers (age 18.1±2.6 years, weight 77.2±10.2 kg, BMI 25.2±2.9 kg · m^?2; mean±s) were randomly assigned to an experimental (loss of 3–4% of their weight through 10-min bouts in dry sauna) or a control (dry sauna exposure with mineral water proportionate to their body weight loss) group. Blood and urine sampling, 12-lead ECG, and echocardiogram were recorded in euhydration, dehydration, and 18 h after sauna. Moreover, a 6-min high-intensity arm ergometer cranking test (8×15 s intervals at maximum workload and 30 s active recovery) was completed in each of the three stages. Data were analysed with repeated-measures analysis of variance, independent t-tests, and Pearson correlations. Dehydration by 3–4% of body weight in sauna resulted in augmentation of the sum of amplitudes of P waves and QRS complexes (mm), but decreased left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), and stroke volume (ml). As expected, rehydration was associated with recovery of the P wave and ECG parameters. In general, QRS amplitude correlated poorly with LVESV, LVEDV, and P wave, but was inversely related to stroke volume (r=–0.387, P=0.011). In conclusion, dehydration in Greco-Roman wrestlers results in physiological alterations (amplitude of the P wave and QRS complex, LVESV, LVEDV, and stroke volume) of the electrical properties of the passive volume conductor. Further research is necessary to assess the potential for adverse events and appropriateness of this short-term weight loss strategy for young wrestlers or other populations.     

Early association of electrocardiogram alteration with infarct size and cardiac function after myocardial infarction

INTRODUCTIONInpatientswithcongestiveheartfailurespe-cificelectrocardiogram(ECG)alterations,suchaspathologicalQwavesorpersistentSTsegmentelevationsinMI-relatedleads,maybeseenaftertransmuralmyocardialinfarction(MI).Infarctex-pansionoccurswithinhoursofmyocyteinjury,resultsinwallthinningandventriculardilation,andcausestheelevationofdiastolicandsystolicwallstresses(Warrenetal.,1988).Ventricularremod-elingmaycontinueforweeksormonthsuntilthedistendingforcesarecounterbalancedbythetensilestren…