心肌细胞电生理和临床心电图进展

心肌细胞电生理是临床心电图的理论基础。心肌细胞跨膜动作电位是理解和解释体表心电图的理论依据。心肌细胞跨膜动作电位图 (ＡＰＧ ,ａｃｔｉｏｎ -ｐｏｔｅｎｔｉｏｎ - ｇｒａｍ )的 0位相和 1,2 ,3位相分别反应在体表心电图 (ＥＣＧ ,ｅｌｅｃｔｏｃａｒｄｉｏｇｒａｍ )为ＱＲＳ ,和ＳＴ -Ｔ波。近年来 ,随着临床心脏电生理学研究的深入和心律失常介入治疗的广泛应用 ,大大提高了对复杂心律失常的认识 ,特别是显性旁道的体表心电图定位、窄ＱＲＳ波心动过速的鉴别诊断、宽ＱＲＳ波心动过速的鉴别诊断 ,应用体表心电图鉴别长ＱＴ间期综…     

高氟对大鼠心肌电生理及心电图的影响

为观察高氟对大鼠心肌电生理及心电图的影响,给两组（每组１０只）Ｗｉｓｔａｒ大鼠饲喂正常饲料,分别饮用１．５８ｍｍｏｌ／Ｌ,２．６３ｍｍｏｌ／Ｌ高氟水。;实验８个月时测定尿氟含量;描记心电图;处死动物行心肌电生理检查,同时留取血清测氟含量。结果显示：两组大鼠尿氟,血清氟含量升高;心肌细胞动作电位的ＲＰ,ＡＰＡ均降低,Ｖｍａｘ减慢,ＡＰＤ５０,ＡＰＤ９０均缩短;心电图Ｔ波振幅降低,Ｑ－Ｔ间期缩短。高氟     

临床心脏电生理标测技术及应用现状

1980年之前,心脏电生理主要用于证实心律失常的发生机制,药物为主要的干预手段,对抗心律失常药物副作用的认识激发了非药物治疗特别是射频消融手术和心脏置入转复器的应用研究.     

思维导图在心电图教学实践中的应用

目的 探讨基于思维导图在医学生心电图教学实践中的应用及其教学效果.方法 选择首都医科大学2016、2017级临床医学研究生24名随机分为改进组及对照组2组,各12名,开展为期32学时心电图临床教学活动,改进组以思维导图为核心进行教学活动,对照组按照既往常规的心电图临床教学方法进行.对两组医学生分别在心电图实习开始前及结...     

实验猪心脏传导系统的电生理特征

目的 阐明实验猪心脏电传导系统的解剖结构和电生理特征。方法 3头雄性健康成年猪,体重（79.0±9.5）kg,利用超高密度三维标测和CT三维重建技术,探究实验猪心脏电传导系统解剖结构及其毗邻组织位置关系,构建电解剖图、电压图及电激动图。利用HE染色及Bielschowsky神经组织染色法,进一步分析心脏传导系统细胞及神经纤维结构。结果 超高密度三维标测法构建的电激动图、电压图、心电传导参数与CT三维重建及组织病理学神经特殊染色结果相符,三维标测所示心脏传导系统位置与镜下P细胞及神经纤维富集部位一致。结论 本研究通过心脏三维标测方法获取的实验猪电传导系统解剖结构和电生理特征数据可靠,可为医疗器械研发和心血管疾病基础研究提供有效数据支持。     

心脏三维电解剖标测在导管射频消融术治疗阵发性室上性心动过速患者中的应用

目的 探讨心脏三维电解剖标测在导管射频消融术治疗阵发性室上性心动过速患者中的应用。方法 选取2018年10月至2020年4月中国人民解放军联勤保障部队第九〇四医院诊治的阵发性室上性心动过速患者87例,根据治疗方法不同分为对照组41例和观察组46例。对照组在X线透视下完成导管射频消融术治疗,观察组在心脏三维电解剖标测系统下完成导管射频消融术治疗,术后完成6个月随访。比较两组消融成功率、手术时间、X线辐射量、并发症及复发率;对患者复发情况进行单因素分析及多因素Logistic分析。结果 两组术后1、3个月复发率无统计学意义(P> 0.05);观察组术后并发症发生率及术后6个月复发率均低于对照组(χ²=5.002、5.002,P <0.05);观察组X线辐射剂量和辐射时间低于对照组(t=10.936、11.322,P <0.05)。87例患者6个月随访时未有患者死亡,将复发2例作为复发组,其余作为未复发组,进行单因素分析,结果显示两组手术方法差异有统计学意义(χ²=7.297,P <0.05)。多因素Logistic回归分析...     

预激综合征旁道的心电图、心脏标测定位(附六例报告)

对6例预激综合征旁道进行心电图、电生理检查及心外膜标测定位和比较,结果提示综合二种心电图δ波极性作旁道定位的方法有较高的准确性。电生理检查对确定左或右旁道的存在有帮助,而作心内膜标测确定旁道位置较困难。认为显性预激综合征者,旁道切割术前不必强调作电生理检查,除非为隐匿性预激。用手指压迫预计的旁道部位,使δ波消失和/或阵发性室上性心动过速终止可能是心外膜标测的一种简便的方法。     

窄QRS心动过速体表心电图鉴别指标与心脏电生理检查结果的对比分析

窄 QRS心动过速是临床上常见的快速性心律失常 ,各型心动过速有其各自的心电图及电生理特征。本文对 76例窄 QRS心动过速发作时体表心电图 ( ECG)与心脏电生理检查结果对比分析 ,寻求各种预测指标对心动过速时 ECG鉴别诊断的价值。资料与方法临床资料 76例患者 ,男性 39例 ,女性 37例 ,平均年龄 42± 1 4岁。其中 6例合并冠心病 ,余 70例心脏结构和功能正常。所有病例均有完整的心内电生理检查资料及窦性心律和心动过速发作时完整记录的体表 1 2导联 ECG资料。ECG分析指标包括 :( 1 )心动过速周长 ( ms) ;( 2 )有无逆传 P-波出现及…     

通过心脏电生理检查探讨心电图诊断中的若干问题

随着射频导管消融（下称消融）治疗快速型心律失常的不断开展,心脏电生理知识迅速得到更新,促进了对心电图知识的重新认识.但部分心电图医师由于无法接触到电生理检查,对一些心电现象的形成机制认识的较模糊,存在某些概念不清或诊断错误的情况.现根据我们的经验体会,结合心脏电生理检查结果探讨在心电图诊断中存在的几个常见问题,希望引起同道对心脏电生理检查的关注.     

A teaching hospital's experience applying the Pneumonia Severity Index and antibiotic guidelines in the management of community-acquired pneumonia

BACKGROUND AND OBJECTIVES: The Pneumonia Severity Index (PSI) was developed to predict mortality in community-acquired pneumonia (CAP). It has been prospectively validated to identify patients who are at low risk of death and thereby aid in the selection of patients for outpatient management. This study assessed the compliance of medical staff at a university teaching hospital with the use of the PSI and the PSI-based local antibiotic guidelines in admitted patients. METHODS: This was a retrospective study of 137 consecutive adults admitted with a primary diagnosis of CAP between July and December 2003. Implementation of the PSI and local antibiotic guidelines occurred 4 months prior to the study period. The data collected included patient demographics, PSI parameters, patient outcomes, adherence and compliance with the PSI scoring process and local antibiotic guidelines. RESULTS: Forty per cent of all CAP admissions were patients in PSI Class I to III. The compliance with scoring the PSI was low (45 out of 137 patients; 33%), as was the accuracy of the PSI scoring (26 out of 45 patients; 58%). Compliance with the local antibiotic guidelines was 87% in patients in whom the PSI was performed. CONCLUSIONS: In admitted patients, non-adherence with the PSI admission guidelines was common. Compliance with scoring the PSI and its scoring accuracy was low. This may be due to a lack of awareness and its relative complexity. Further studies to identify potential barriers to compliance are warranted.     

Brugada phenocopy: A new electrocardiogram phenomenon

Brugada phenocopies(BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram(ECG) patterns in precordial leads V1-V3. However, BrP are elicited by various un-derlying clinical conditions such as myocardial ischemia, pulmonary embolism, electrolyte abnormalities, or poor ECG filters. Upon resolution of the inciting underlying pathological condition, the BrP ECG subsequently nor-malizes. To date, reports have documented BrP in the context of singular clinical events. More recently, recur-rent BrP has been demonstrated in the context of re-current hypokalemia. This demonstrates clinical repro-ducibility, thereby advancing the concept of this new ECG phenomenon. The key to further understanding the pathophysiological mechanisms behind BrP requires experimental model validation in which these phenom-ena are reproduced under strictly controlled environ-mental conditions. The development of these validation models will help us determine whether BrP are tran-sient alterations of sodium channels that are not repro-ducible with a sodium channel provocative test or al-ternatively, a malfunction of other ion channels. In this editorial, we discuss the conceptual emergence of BrP as a new ECG phenomenon, review the progress made to date and identify opportunities for further investiga-tion. In addition, we also encourage investigators that are currently reporting on these cases to use the term BrP in order to facilitate literature searches and to help establish this emerging concept.     

T波形成的心肌电生理学研究进展

Ｅｉｎｔｈｏｖｅｎ将心电图应用于临床以来 ,迄今已一百年 ,在心脏疾病的诊断中具有极为重要的价值。但是 ,心电图正常和异常波形的形成原理 ,至今尚不十分清楚。心肌细胞电生理学研究的开始 ,比心电图的临床应用晚了半个世纪。自上世纪８０年代以来 ,虽然研究已经深入到细胞、分子水平 ,但主要是研究细胞膜和细胞内小器离子通道的生理、药理特性 ,病理变化以及心律失常发生原理和抗心律失常药物等 ,较少研究心电图波形的形成原理。这是由于人们在指导思想上认为心脏是一个合体细胞 ,没有注意到心肌细胞之间可能存在差异 ,反映在研究技术上…     

医学本科生心电图见习教学方法探索

目的 探索一种普适性强的本科生心电图高效见习教学方法。 方法 在有限学时,设计了“两段三步八环节”的见习教学方法,通过课后调查问卷、见习前后读图测试成绩以及与前一学年招生背景相似但见习方法不同的学生见习后测试成绩对比,评价教学效果。 结果 98.7 %的学生认为这种见习方式有助于提高读图能力,85.3%的学生认为学习心电图的兴趣得到了提高,78.7%的学生认为自己基本掌握了心电图分析方法,61.3%的学生认为自己的读图能力有了显著提高。见习前后两次测试成绩比较,见习后明显好于见习前（P<0.05）。对比2017级和2016级长学制学生的见习后测试成绩。两者招生模式相同,心电图见习后测试的考题完全一致(考题严格保密不泄露),结果发现两组成绩的差异没有统计学意义。 结论 教学组探索了一套学时压缩的高效实用的心电图见习教学方法。对这套方法加以调整,便可应用于非疫情时期的线下见习,当未来需要进行线上见习时,教学组的方法同样适用。     

Clinical and electrophysiological aspects of median intra-His bundle block with normal electrocardiogram at rest

The clinical and electrophysiological features and the natural history of median intra-His block with a normal resting electrocardiogram were studied: 11 patients had a fixed split H1-H2 potential with a spontaneous or induced block between H1 and H2. The patients (5 men and 6 women) were aged 17 to 70 years (average 53 years). Associated pathology included 2 cases of aortic stenosis (1 severe), 1 case of ischaemic heart disease (effort angina), 1 case of mitral valve prolapse and 2 cases of hypertension. The presenting symptoms were syncope (4 cases), dizziness (2 cases), effort angina (1 case) and tiredness (3 cases); 1 patient was asymptomatic. Holter monitoring (24 hours) was performed in 8 patients and s-owed paroxysmal conduction defects in 6 cases; 4 Mobitz II 2nd degree AV block, 1 3rd degree AV block with narrow QRS complexes and 1 case of blocked atrial extrasystoles at coupling intervals longer than 480 ms and sinus cycle lengths of over 800 ms. Exercise testing by bicycle ergometry (4 patients) was normal in 1 case and revealed Mobitz II 2nd degree AV block in 3 cases. Baseline electrophysiological studies showed an A-H1 interval ranging from 60 to 100 ms (average 78 ms), a H1-H2 interval of 20 to 40 ms (average 31 ms) and a H2-V interval of 30 to 50 ms (average 32 ms). Block between H1 and H2 was observed: "spontaneously" during electrophysiological investigation in 6 cases, after IV atropine in 1 case, during overdrive atrial pacing at rates slower than 150/min in 7 cases, after atrial extrastimulus with a functional intra-His refractory period of over 420 ms in 7 cases, after ajmaline in 3 of the 4 cases in which this test was performed. A cardiac pacemaker was implanted in 10 patients in whom the initial symptoms have all regressed; the remaining patient considered to be "epileptic" had another syncopal attack under therapy and was finally paced. This series demonstrates that the diagnosis of median intra-His block depends on precise electrophysiological criteria and should be looked for even when the presenting symptoms are atypical; some of our patients complained only of tiredness. The value of Holter monitoring and careful endocavitary investigation is emphasised. Median intra-His block should be distinguished from longitudinal and functional His bundle dissociation.     

A new technique for simultaneous monitoring of electrocardiogram and walking cadence.

A new technique for simultaneously recording continuous electrocardiographic (ECG) data and walking step rate (cadence) is described. The ECG and gait signals are recorded on 2 channels of an ambulatory Holter monitor. Footfall is detected using ultrathin, force-sensitive foot switches and is frequency modulated. The footfall signal provides an indication of the subject's activity (walking or standing), as well as the instantaneous walking rate. Twenty-three young and elderly subjects were studied to demonstrate the use of this ECG and gait recorder. High-quality gait signals were obtained in all subjects, and the effects of walking on the electrocardiogram were assessed. Initial investigation revealed the following findings: (1) Although walking rates were similar in young and elderly subjects, the elderly had both decreased heart rate (HR) variability (p < 0.005) and increased cadence variability (p < 0.0001). (2) Overall, there was an inverse relation between HR and cadence variability (r = -0.73). Three elderly subjects with no known cardiac disease had HR and cadence variability similar to those of the young, whereas elderly subjects with history of congestive heart failure were among those with the lowest HR variability and the highest cadence variability. (3) Low-frequency (approximately equal to 0.1 Hz) HR oscillations (frequently observed during standing) persisted during walking in all young subjects. (4) In some subjects, both step rate and HR oscillated at the same low frequency (approximately equal to 0.1 Hz) previously identified with autonomic control of the baroreflex.(ABSTRACT TRUNCATED AT 250 WORDS)     

应用三维磁导航系统标测和消融快速性心律失常的初步经验

目的观察三维磁导航系统标测和消融快速性心律失常的疗效。方法结合NiobeII磁导航系统和CARTO-RMT电解剖标测系统,采用4mm-顶端的NaviStar-RMT标测和消融导管进行射频消融治疗快速性心律失常。结果10例患者,男6例,女4例。房室结折返性心动过速4例,其中1例合并阵发性心房颤动,左侧房室旁道2例,右侧房室旁道1例,典型心房扑动2例,右室流出道室性心动过速1例。磁导航系统遥控操作,10例均完成电生理标测。9例消融成功,失败1例为心房扑动患者,换用NaviStar盐水灌注导管后消融成功。导管操作时间93±33.1min,X线曝光时间12.5±6.5min。随访6个月无复发。结论对于快速性心律失常,应用磁导航系统可进行有效和安全的三维标测和消融。