SaVR电压标准与RV5(6)+SV1电压标准联用诊断左室肥厚的价值

目的:探讨心电图aVR导联的S波电压在诊断左室肥厚(LVH)中的价值.方法:以超声心动图结果为诊断标准,测量LVH者60例(A组)及无LVH者40例(B组)的心电图RV5(6) SV1电压和SaVR电压,计算RV5(6) SV1电压标准和SaVR电压标准及两者联用标准诊断LVH的敏感性、特异性及准确性,并进行显著性检验.结果:① SaVR电压标准诊断LVH的敏感性低(36.6%),特异性高(100%),准确性为62.0%;② RV5(6) SV1电压标准诊断LVH的敏感性(58 3%)较SaVR电压标准高,但特异性下降(85.0%),准确性为69.0%;③两者联用诊断LVH的敏感性及准确性提高,特异性无明显降低,分别为:73.3%、78.0%、85.0%.两者联用中,A组有44例、B组有6例符合LVH的心电图标准.结论:SaVR电压标准诊断LVH具有实用价值,与RV5(6) SV1电压标准联用更理想,可弥补单用的不足.     

Evaluation of the electrocardiogram RV5/V6 criteria in the diagnosis of left ventricular hypertrophy in marathon runners

To assess the value of electrocardiogram (ECG) RV5/V6 criteria for diagnosing left ventricular hypertrophy (LVH) in marathons. A total of 112 marathon runners who met the requirements for “Class A1” events certified by the Chinese Athletics Association in Changzhou City were selected, and their general clinical information was collected. ECG examinations were performed using a Fukuda FX7402 Cardimax Comprehensive Electrocardiograph Automatic Analyser, whereas routine cardiac ultrasound examinations were performed using a Philips EPIQ 7C echocardiography system. Real-time 3-dimensional echocardiography (RT-3DE) was performed to acquire 3-dimensional images of the left ventricle and to calculate the left ventricular mass index (LVMI). According to the LVMI criteria of the American Society of Echocardiography for the diagnosis of LVH, the participants were divided into an LVMI normal group (n = 96) and an LVH group (n = 16). The correlation between the ECG RV5/V6 criteria and LVH in marathon runners was analysed using multiple linear regression stratified by sex and compared with the Cornell (SV3 + RaVL), modified Cornell (SD + RaVL), Sokolow–Lyon (SV1 + RV5/V6), Peguero–Lo Presti (SD + SV4), SV1, SV3, SV4, and SD criteria. In marathon runners, the ECG parameters SV3 + RaVL, SD + RaVL, SV1 + RV5/V6, SD + SV4, SV3, SD, and RV5/V6 were able to identify LVH (all p < .05). When stratified by sex, linear regression analysis revealed that a significantly higher number of ECG RV5/V6 criteria were evident in the LVH group than in the LVMI normal group (p < .05), both with no adjustment and after initial adjustment (including age and body mass index), as well as after full adjustment (including age, body mass index, interventricular septal thickness, left ventricular end-diastolic diameter, left ventricular posterior wall thickness, and history of hypertension). Additionally, curve fitting showed that the ECG RV5/V6 values increased with increasing LVMI in marathon runners, exhibiting a nearly linear positive correlation. In conclusions, the ECG RV5/V6 criteria were correlated with LVH in marathon runners.     

心电图诊断左室肥大的标准化探讨

目的探讨心电图诊断左室肥大的标准化。方法通过心电网络信息系统回顾常州二院阳湖院区的心电图图文报告,对比心超结果探讨左室肥大(左室肥厚和(或)左室扩大)的心电图诊断标准。结果认为以左室高电压伴ST-T改变为必要条件诊断左室肥大较合适(检出率69.39%,符合率55.68%);若合并电轴左偏和(或)QRS≥100 ms,则诊断符合率明显增高。结论单纯左室肥厚仅表现左室高电压伴ST-T改变;而左室高电压伴ST-T改变合并电轴左偏的情况下,左室肥厚与左室扩大可能相当;左室高电压伴ST-T改变合并QRS≥100 ms则以左室扩大为主。     

胸前导联最大QRS波振幅诊断左室肥厚的研究

目的通过验证如下两项基本假设提出心电图(ECC)诊断左室肥厚(LVH)的新指标:①胸导联最大QRS振幅(Vmax)应该比某一特定导联的R或S波能更好地反映左室心肌重量(LVM);②体重/身高比值(WT/HT)可近似地代替左室中心到胸壁距离的平方而用以校正胸导联QRS振幅。方法将76例高血压患者常规12导联心电图与M型超声心动图左室心肌重量(LVM)及左室心肌重量指数(LVMI)进行分析比较。结果Vmax是与心室重量指数(LVMI)相关最密切的心电图指标(r=0.545,p<0.001)。Vmax乘以WT/HT后,与心室重量指数(LVMI)的相关系数由r=0.442提高到r=0.659(p<0.05)。结论①胸导联最大QRS振幅可能取代常规的电压指标,作为心电图左室肥厚的诊断新指标;②Vmax乘以WT/HT可进一步提高其诊断效能。     

Electrical axis and voltage criteria on left ventricular hypertrophy.

The voltage criteria of left ventricular hypertrophy were studied in 229 hypertensive patients undergoing treatment and 62 patients who were not treated. The limb-lead voltage criterion (R Lead aVL greater than or equal 11 mm.) was found more frequently in patients with radiographic evidence of cardiomegaly than other voltage criteria. This may have been due to a more negative axis in patients with cardiomegaly than in patients without cardiomegaly. It is possible that dilatation of the left ventricle to the left and posteriorly accentuates limb-lead criteria at the expense of V-lead criteria. Left anterior hemiblock occured in less than 10 per cent of the hypertensive patients. In 10 out of 16 patients with left anterior hemiblock, the hemiblock disappeared after treatment of the hypertension for 4 years whereas all five hemiblocks in untreated hypertensives persisted. Development of left anterior hemiblock subsequently occurred in only one patient with treatment and one without treatment over a 4-year period.     

Differential diagnosis between left ventricular hypertrophy and cardiomyopathy in childhood

The sensitivity and specificity of the electrocardiogram for the diagnosis of left ventricular hypertrophy of different etiologies are described. The sensitivity of the electrocardiogram for detecting left ventricular pressure overload is substantially lower (< 35%) than the sensitivity for detecting evidence of a cardiomyopathy (55% to around 87%). Attention is drawn to the finding that in many differing etiologies of left ventricular hypertrophy ST-T-wave changes commonly referred to as “strain”-pattern are a harbinger of an increased risk of malignant cardiac arrhythmias and sudden death.In the most common pediatric cause of sudden death, hypertrophic cardiomyopathy, a described ECG risk score, which scores both voltage and repolarization abnormalities, is the most powerful predictor hitherto described for predicting the risk of sudden death in this diagnosis. A point score over 5 points gives a relative risk for sudden death of 24.3 with a sensitivity of 96% and a specificity of 78% in childhood.     

V_1、V_2、V_3的S波及Ⅰ、Ⅱ、aVL的R波之和在诊断左室肥大中的价值

目的探讨诊断左室肥大(LVH)新的心电图指标。方法以超声心动图测定的左室重量(LVM)及重量指数(LVMI)为对照,其诊断LVH的标准为>125g/m2(男),120g/m2(女),对100例正常健康人及111例患者进行了观察,对12导联QRS总振幅(∑QRS)、V1～V3导联的S波之和(∑SV1～V3)、Ⅰ、Ⅱ、aVL导联的R波之和(∑RⅠ、Ⅱ、aVL)及后两者之和(Z表示),分别进行了测定。寻找新指标的正常值范围以及以此标准为依据,诊断LVH的灵敏度、特异度、准确率。结果正常组中,∑QRS、∑SV1～V3、∑RⅠ、Ⅱ、aVL及Z值正常范围分别为77～175,11～38,5～23及22～54mm,以大于这些指标的正常值上限为标准,其诊断LVH灵敏度、特异度及准确率较传统指标明显提高,其中Z值>54mm灵敏度最高(86.54%),准确率最高(90.09%),而特异度仍保持在93.22%。结论LVH新的心电图指标具有一定诊断价值,其中Z>54mm最好。     

心电图电压标准诊断左室肥大价值的研究

目的 评价临床上最常用的几项心电图电压标准诊断左室肥大（LVH）的价值及性别差异。方法 选择1999—2003年我院体检及住院患者499例，依据超声心动图测定的左室重量指数（LVMI）分为正常组（男210饲，女83例）和左室肥大组（男126例，女80例）。计算各项电压标准诊断左室肥大的敏感性、特异性和准确率，并比较各项电压标准诊断左室肥大的性别差异。结果 各项电压标准诊断左室肥大的特异性均〉95％,在单项指标中，Rvs〉2．5my标准的敏感性和准确率分别为62．8％和85．1％，明显高于Rvs及RaVL电压标准。在复合指标中，Comell指数和Sokolow指数诊断左室肥大的敏感性和准确率明显高于R4＋Sm指标。男、女性采用相同的电压阈值，其诊断性能存在明显性别差异。结论 Cornell指数、Sokolow指数及Rv5电压标准是诊断左宣肥大较好的指标。男、女性采用不同的电压阈值标准，可望进一步改善目前心电图诊断左室肥大的性能。     

用心电图胸前导联最大QRS电压及其与体重/身高比值乘积诊断左心室肥厚

用心电图的常规电压标准诊断左心室肥厚因受多种因素的影响而不敏感也不特异。心脏病学家始终在为提高心电图诊断左心室肥厚的敏感性不懈努力 ,但截止目前 ,这些尝试使心电图诊断左心室肥厚准确性的提高依然十分有限。根据心电发生的基本原理提出假设 ,期望与常规指标不同的新途径 (胸前导联最大ＱＲＳ电压 )能成为心电图诊断左心室肥厚的较好指标 ,并设想体重 /身高比值可近似地代替左心室到胸壁距离的平方而用以校正胸前导联ＱＲＳ电压。由于高血压左心室肥厚的重要性以及心电图诊断高血压左心室肥厚的低敏感性特点 ,选择高血压患者为研究…     

Potentiation of reperfusion-associated ventricular fibrillation by left ventricular hypertrophy

Important electrophysiological alterations that may predispose hearts to arrhythmias have been described for hypertrophied myocytes, and hypertrophy coupled with ischemia has been associated with an increased incidence of sudden death; however, an influence of hypertrophy on reperfusion arrhythmias has not been previously described. We hypothesized that reperfusion-associated arrhythmias would be potentiated by left ventricular hypertrophy. After induction of renovascular hypertension, 37 awake, unsedated dogs (17 with left ventricular hypertrophy and 20 without hypertrophy) underwent 15 minutes of coronary artery occlusion and reperfusion. All dogs were pretreated with lidocaine bolus injections and with lidocaine by continuous infusion during coronary occlusion and reperfusion. Reperfusion-associated ventricular fibrillation occurred in seven of 17 dogs with left ventricular hypertrophy versus one of 18 dogs without hypertrophy (p less than or equal to 0.05). The presence of hypertension was not significantly associated with an increased incidence of reflow ventricular arrhythmias. Neither QT interval nor area-at-risk was different between the dogs with and without reperfusion ventricular fibrillation; however, increased heart rate just before reperfusion did correlate with an increased incidence of ventricular fibrillation at reperfusion. Thus, 1) left ventricular hypertrophy was associated with a significantly increased incidence of reperfusion-induced ventricular fibrillation after 15 minutes of ischemia, 2) this increased incidence was independent of the presence of hypertension, and 3) lidocaine protected control and hypertrophied hearts against ventricular fibrillation during ischemia but was ineffective in protecting hypertrophied hearts against reperfusion-induced ventricular fibrillation.     

Determinants of sensitivity and specificity of electrocardiographic criteria for left ventricular hypertrophy

Numerous electrocardiographic criteria, which are largely dependent on fixed voltage thresholds, have been proposed for the diagnosis of left ventricular hypertrophy (LVH). Electrocardiographic criteria for LVH were examined in 4,684 subjects of the Framingham Heart Study who underwent echocardiographic study for LVH. Echocardiographic LVH was detected in 290 men (14.2%) and 465 women (17.6%). Electrocardiographic features of LVH were present in 2.9% of men (60/2,042) and 1.5% of women (39/2,642). The overall sensitivity of the electrocardiographic diagnosis of LVH was 6.9%, whereas specificity was 98.8%. Sensitivity of the electrocardiogram (ECG) for LVH was marginally lower in women than in men (5.6% vs. 9.0%, p = 0.075). Obesity was inversely associated with sensitivity (p less than 0.05, both sexes combined, sex-adjusted). Smoking was also inversely related to sensitivity (p = 0.001, both sexes combined, sex-adjusted). In contrast, sensitivity of the ECG increased with age (p less than 0.001, both sexes combined, sex-adjusted). These findings suggest that electrocardiographic detection of LVH can be improved by incorporating information about noncardiac factors that impact on electrocardiographic sensitivity for LVH, presumably by attenuating QRS voltage. New strategies that take into consideration sex, age, smoking status, and obesity might improve the sensitivity of the ECG without diminishing specificity.     

Influence of left ventricular hypertrophy on scar identification during bipolar voltage mapping

Purpose  

Bipolar endocardial signal amplitude (BESA) <1.5 mV defines scar in the left ventricle (LV). It is not known if LV hypertrophy (LVH) increases overall bipolar signal amplitude and if scar identification with LVH requires a higher voltage cutoff.