重建心向量图与常规心向量图,心电图诊断价值的比较

我们在同一病例组上对两个计算机诊断系统的诊断价值进行了比较。两个系统中，一个完成对心电图的解释，另一个完成对心向量图和重建心向量图的解释。病例组总数为２６２５例，其中正常人１０６５例，左心室肥大２１６例，右心室肥大３４例，双心室肥大２３例，前壁心梗３４０例，下壁心梗７００例，复合心梗２４７例。结果显示，重建心向量图具有与常规心向量图类似的诊断精度，将这个由心电图推算而来的诊断与心电图并用，可以提高心电图对正常、左心室肥大以及复合心梗的诊断正确率。提示重建心向量图在多种疾病的诊断中具有一定价值，存在于常规心向量图中的诊断信息也存在于同步记录的心电图中，对后者的利用可以提高心电图的诊断价值。     

时间心向量图和连续心向量图的临床应用

时间心向量图和连续心向量图的临床应用王云翔罗北捷佟万仁舒筑和易周（解放军三零四医院心内科北京１０００３７）关键词心电向量描记术长期以来，心向量图主要用于心肌梗塞、束支或分支传导阻滞、心室肥厚、心室预激等疾病的诊断，而不能涉足心律失常，其主要原因是以往...     

计算机心电图与计算机心向量图的联合应用

本研究利用两个计算机自动诊断系统，一个对心电图，一个对心电向量图进行分析，完成了对国际标准心电图库的联合诊断，产观察了单独诊断之间，单独诊断与联合诊断之间的差异，以进一步探讨心电图与心电向量图在诊断上的互补效应，以及ＣＳＥ研究中关于联合诊断优于单独诊断的机制。国际标准心电图库由１２２０个病例构成，其中正常者３８２例，左室肥大１８３例，右室肥大５５例，双室肥大５３例，前壁心梗１７０例，下壁心梗２７３     

心肌梗死患者心电向量图与心电图对比分析

心电向量图 (VCG)和心电图 (ECG)均为记录心脏电激动的方法 ,前者观察立体的变化 ,后者观察平面的变化。作者对 5 5例心肌梗死患者分别行追踪检查以比较其诊断价值。1　对象和方法1.1　对象　 5 5例均为 1992 - 10～ 1998- 12心血管内科的住院患者。其中男 48例 ,年龄 42～ 75岁 ,女 7例 ,年龄 46～ 73岁。 5 5例患者均经血清酶学 ,VCG,ECG、心脏 B超等检查 ,临床确诊为心肌梗死患者 ,其中有 10例是下壁心肌梗死伴左前分支传导阻滞。1.2　仪器与方法　 VCG检查采用河南省新乡产 HX- 6 0 2型心电向量微机系统和美国产 ECG L ABTM…     

高频心电图、心向量图和动态心电图对冠心病诊断价值的比较

高频心电图、心向量图和动态心电图对冠心病诊断价值的比较胡观涛（浙江省武义县第一人民医院武义３２１２００）关键词冠状动脉疾病高频心电描记术心电向量描记术心电描记术，便携式高频心电图（ＨＦＥＣＧ）未用于心血管病临床之前，心向量图（ＶＣＧ）Ｔ环异常和动态心...     

大鼠急性心肌缺血早期心电图QRS波群和ST段改变

目的利用大鼠心肌缺血模型,观察大鼠急性心肌缺血早期QRS波群和ST段变化及二者的关系。探讨大鼠缺血模型的成功标准。方法选用雄性SD大鼠108只,结扎左冠状动脉前降支制作大鼠心肌缺血模型。观察缺血5min内心电图QRS波群和ST段变化。结果①108只大鼠中,心肌缺血后R波明显增高89只(占82.4%),伴QRS波群时间增宽。②108只大鼠心肌缺血5minST段均有明显抬高,但5min内ST段改变过程表现为三种形式:缺血后ST段抬高过程中出现一过性下降,然后又逐渐抬高(60只,占55.6%);缺血后ST段抬高逐渐增加(37只,占34.3%);缺血后ST段先下降,1～5min后出现ST段抬高(11只,占10.2%)。③心肌缺血5min内QRS变化与ST段变化的关系:心肌缺血后R波明显增高的89只大鼠,其ST段出现上述三种改变,R波无明显变化的19只大鼠中,ST段变化均表现为缺血后抬高逐渐增加。R波增高越明显,QRS时间越宽,ST段下移也越明显。结论大鼠左冠状动脉前降支结扎后出现一过性R波增高、QRS波群增宽是心肌急性缺血损伤早期表现,在心电图记录中较ST段变化易于观察,可以作为早期结扎成功的心电图判断标准。     

急性下壁心肌梗死患者心电图胸前导联ST段改变的临床意义

目的探讨急性下壁心肌梗死患者心电图胸前导联ST段改变与冠状动脉造影(CAG)所见冠状动脉病变部位的关系及其临床意义。方法 187例急性下壁心肌梗死患者,按入院时18导心电图胸前导联ST段改变分为3组,ST段无变化组(47例),ST段抬高组(16例),ST段压低组(124例);所有患者均行CAG。结果急性下壁心肌梗死伴胸前导联ST段抬高时多为右冠状动脉(RCA)近段闭塞(14例,82.3%),尤其是伴圆锥支动脉闭塞,与RCA中远端闭塞(2例,5.9%)比较差异有统计学意义(P0.01),且14例(73.7%)伴有右心功能不全和血流动力学障碍。下壁心肌梗死胸前导联ST段压低者可见于RCA、回旋支(LCX)闭塞及RCA、LCX闭塞与前降支(LAD)、对角支(D)病变的不同组合,其中LCX闭塞伴RCA病变者多表现为朐前ST V_4～V_6的压低,RCA闭塞伴LAD近端病变多有胸前ST V_1～V_6的压低,RCA伴D病变胸前ST V_1～V_3压低,与对照组比较差异有统计学意义(P0.05)。结论急性下壁心肌梗死合并胸前导联ST段抬高表明为RCA近段或丌口闭塞且多伴右心室心肌梗死和心功能不全;下壁心肌梗死伴胸前导联ST段压低提示为多支病变,ST V_1～V_3压低多伴有对角支严重狭窄,STV_1～V_6压低多伴有前降支的严重狭窄。     

心向量图横面T环顺钟向运行80例的冠状动脉造影结果分析

一直以来 ,心向量图 (ＶＣＧ)横面Ｔ环顺钟向运行 (顺转 )被视为心肌缺血的表现 ,并以此作为冠心病ＶＣＧ诊断标准之一。本研究对ＶＣＧ横面Ｔ环顺转者进行了冠状动脉造影检查 ,结果如下。1.资料与方法 :随意从我院门诊就诊者及住院患者中 ,选择 5 0岁以下经ＶＣＧ检查为横面Ｔ环顺转者 80例作为观察组 ,男 2 6例 ,女 5 4例 ,年龄 2 2～ 46 (平均 34 .6 )岁。其中 39例临床有心悸、气短、胸闷、乏力等症状 ,屡次体检仅心电图可有ＳＴ、Ｔ改变或早搏 ,其余检查均正常 ;30例临床无症状、无体征 ,心电图检查普遍导联ＳＴ下降 0 .1ｍＶ左右、Ｔ…     

正确解读心电图的ST段和T波改变

针对临床上在解读心电图的ST段和T波改变方面存在某些误解的实际情况,作者愿和读者讨论如何正确解读心电图的ST段和T波改变问题,供大家参考。尽管心电图是一门专业性技术,解释权应该属于医师和这方面的专家,但作者认为广大读者了解心电图的一些基本知识是可能的,是会有帮助的。     

ST changes and temporal relation to the J point during heart rate increase and myocardial ischemia

There is no concensus concerning where in the ST segment to measure. We studied the relation between different J point intervals to ST results during tachycardia and ischemia.Symptomatic (anesthetized) patients with coronary artery disease were paced at ascending incremental levels until they became ischemic. ST vector magnitude and ST vector change from baseline (STC-VM) as well as the sum of ST changes from all 12 electrocardiogram (ECG) leads (ECG ST sum) were measured at J point 0 millisecond, J + 20, J + 60, and J + 80 milliseconds for 34 patients.ST segments increased in similar fashion during pacing and ischemia. There was no difference in ST results when measurement was performed at different time intervals for both STC-VM and ECG ST sum.We conclude that ST assessment by ST change from baseline is not affected by different J point intervals during increased heart rate and ischemia in this clinical model of pacing-induced ischemia and vectorcardiographic ST analysis.     

冠状动脉前降支闭塞致急性心肌梗死的心电图ST段偏移特点分析

目的探讨冠状动脉前降支(LAD)单支闭塞所致急性心肌梗死(AMI)的心电图(ECG)特点。方法回顾性分析51例LAD急性闭塞所致AMI患者心电图ST段改变与冠状动脉造影结果。结果 V_2导联ST段抬高<0.2 mV预测LAD远段闭塞敏感度为52.9%,特异度为88.2%,在胸导联ST段抬高的情况下,特异度增高(96.2%)。V_6导联ST段压低预测LAD近段闭塞敏感度为26.5%,特异度100%,在胸导联ST段抬高的情况下,V_1导联ST段抬高≥0.2 mV预测LAD近段闭塞敏感度53.8%,特异度88.9%。下壁导联Ⅱ、Ⅲ、aVF ST段压低预测LAD近段闭塞特异度较高,Ⅲ、aVF导联组合较Ⅱ、Ⅲ、aVF导联组合判断LAD近段闭塞特异度及阳性预测值高。结论 V_1导联ST段抬高、V_6导联ST段压低、下壁导联ST段压低有助于判断LAD近段闭塞,V_2导联ST段抬高<0.2 mV有助于判断LAD远段闭塞。     

完全性右束支传导阻滞并左前分支阻滞 T环特点及意义

目的:探讨完全性右束支传导阻滞(CRBBB)并左前分支传导阻滞(LAFB)的T环形态及异常的临床价值.方法:对正常人(对照组)和陈旧性心肌梗死患者(OMI组)各50例及心电图(ECG)符合CRBBB加LAFB诊断(CRBBB加LAFB组)84例行心电向量图(VCG)检查.根据临床资料CRBBB加LAFB组分为无器质性心脏病的正常亚组(A组,39例)和有器质性心脏病的异常亚组(B组,45例).分析T向量环改变及临床意义.结果:对照组T环形态多呈狭长型,占96%(48/50);OMI组T环多呈圆小型、狭小型和圆长型,占94.0%(47/50),2组比较差异有统计学意义(P＜0.05).CRBBB加LAFB组:A组T环形态呈狭长型94.9%(37/39);B组T环形态呈圆小型、狭小型和圆长型占84.4%(38/45),2组比较差异有统计学意义(P＜0.05).而A组与对照组比较差异无统计学意义(P＞0.05).结论:CRBBB加LAFB者VCG示T环呈圆小型、狭小型与心肌缺血有关,T环呈狭长型可能为传导系统原发性退行性变所致.     

Normal values of the ventricular gradient and QRS-T angle,derived from the pediatric electrocardiogram

Background

Normal values of the mathematically-synthesized vectorcardiogram (VCG) are lacking for children. Therefore, the objective of this study was to assess normal values of the pediatric synthesized VCG (spatial QRS-T angle [SA] and ventricular gradient [VG]).

Day-to-day variation of the Frank electrocardiogram and vectorcardiogram in heart disease

Day-to-day variation of the Frank electrocardiogram and vectorcardiogram was studied in 20 patients with clinically stable hypertensive and/or coronary heart disease. Ten recordings were made on each patient during two consecutive five-day periods separated by a two-day weekend. Fifty-four selected measurements including durations, amplitudes, amplitude ratios, spatial magnitudes, and angles were computed on each of the records. Mean and maximal day-to-day variations of these measurements were compared with variations observed in 20 normal subjects reported in a previous study.Although considerable repeat variability was observed for several parameters, the magnitude of variability was not significantly different from that in normal subjects. However, abrupt and marked change in the electrocardiographic pattern seen in two patients suggests that sudden alterations in conduction may be common in patients with heart disease.The data presented can be helpful in assessing the significance of variations observed in serial electrocardiography in clinical practice.     

Vectorcardiographic ST deviations related to increased heart rate in the absence of ischemia in an experimental pig model

The electrocardiographic ST segment may change when heart rate (HR) increases. We aimed to analyze vectorcardiographic ST relation and myocardial conditions during controlled HR increases in anesthetized pigs. The relative parameters ST change vector magnitude and ST change vector angle were calculated at paced HRs ranging from 85 to 175 beats per minute. ST change vector magnitude increased from baseline 6.3 +/- 1.3 to 26.0 +/- 3.1 microV (P < .01; range, 4-50 microV) at HR 175 beats per minute with similar changes in ST change vector angle, whereas the absolute parameter ST vector magnitude demonstrated a heterogeneous pattern without any systematic relation to HR changes. Microdialysis results from left ventricular wall, with analysis of glucose, lactate, and pyruvate, showed no sign of ischemia during pacing. Potassium concentrations did not change during pacing. We conclude that significant HR-related ST vector changes can occur in the absence of myocardial ischemia.     

Quantitative assessment of ST segment elevation in Brugada patients

BACKGROUND: ST segment elevation in the right precordial leads constitutes the electrocardiogram (ECG) hallmark of Brugada syndrome (BS). This pattern is variable and can be concealed, but the magnitude and the cause of ST segment fluctuations have been poorly investigated. OBJECTIVE: Our goal was to quantify ST changes and to assess rate and autonomic influences on ST level. METHODS: A 12-lead ECG was continuously recorded during 24 hours in 20 patients with BS (ages 49 +/- 12) and 10 healthy subjects (ages 32 +/- 7). Using two-dimensional binning we obtained average QRS-T complexes every 30 minutes (time bins) and at different RR intervals (rate bins) for each subject. ST level was measured at five different points located 90, 100, 110, 120, and 140 ms after Q onset (Qo). In BS patients, the highest ST elevation was measured 110 ms after Qo (Qo+110). RESULTS: ST level changes between time points were significantly greater in patients with BS compared with control subjects: on lead V2, the range of ST level at Qo+110 was 264 +/- 85 microV in BS and 91 +/- 22 microV in control subjects (P <.01). In BS, ST level decreased with heart rate acceleration: the difference in ST level at Qo+110 for RR = 900 and 600 ms was 55 +/- 53 microV (P <.01). HFnu was positively, although weakly, correlated with ST level (R(2) = 0.02, P <.01). CONCLUSIONS: ECG changes observed in patients with BS are related in part to heart rate influences on ST segment level. These spontaneous fluctuations over a 24-hour time period suggest that Holter recordings may improve the ECG diagnosis sensitivity in BS.     

急性心肌梗死时心电图不同形态ST段抬高的机制和意义

目的 :探讨急性心肌梗死时心电图不同形态 ST段抬高的机制和意义。方法 :结扎家兔冠状动脉的不同分支制造急性心肌梗死模型。结果 :ST段抬高的形态随心肌缺血时间的延长而呈“下弧形—上斜形—上弧形”的规律性变化。结论 :ST段抬高的不同形态反映心肌损伤的不同时相 ,下弧形抬高提示心肌缺血的早期 ,上弧形抬高提示心肌损伤的晚期 ,上斜形抬高介于二者之间。