老年男性心电图Cornell电压标准及其应用价值

目的 探讨老年男性心电图Comell电压标准及其诊断老年男性左室肥厚的价值.方法 回顾性分析北京医院自1990年来进行尸体解剖的老年男性患者资料,排除心电图ORS波时限≥0.12 s及起搏心电图的患者.测量死亡前3个月内标准12导联心电图QRS波振幅,分析老年男性Comell、Sokolow-Lyon电压值与左室前壁厚度的相关性.计算老年男性无器质性心脏病组Comell电压值的均数及其97.5%的上限值,分析老年男性心电图Comell电压标准诊断老年男性左室肥厚的敏感性、准确性.结果 老年男性心电图Comell、Sokolow-Lyon电压值与左室前壁厚度相关.老年男性无器质性心脏病组心电图Sv3+RaVL平均值为(1.32±0.79)mV,以其97.5%的上限值2.9 mV为Comell标准诊断老年男性左室肥厚的敏感性、准确性分别为34.3%、77.5%,高于Sokolow-Lyon标准.结论 心电图Comell电压标准诊断中国老年男性左室肥厚的界值可采用2.9 mV,其诊断老年男性左室肥厚的敏感性、准确性高于Sokolow-Lyon标准.     

心电图诊断老年男性左心室肥厚的价值

目的 探讨心电图诊断老年男性左心室肥厚的价值.方法 回顾性分析我院自1990年进行尸体解剖的老年男性患者资料,排除心电图QRS波时限≥10.12 s及起搏心电图的患者,测量死亡前3个月内标准12导联心电图QRS波振幅,分析老年男性不同年龄组心电图QRS波振幅与左心室前壁厚度的相关性.结果 心电图V5、V6、I、aVL导联R波幅度[分别为(1.1±0.7)mV、(0.9±0.6)mV、(0.4±0.3)mV和(0.3±0.3)mV]及心电图左胸导联(V5或V6)R波幅度与右胸导联(V1)S波幅度之和[(1.9±1.2)mV)与左心室前壁厚度[(13.6±5.4)mm]具有相关性(相关系数分别为0.22、0.14、0.22、0.23、0.23;P均<0.05).心电图左胸导联(V5或V6)R波幅度与右胸导联(V1)S波幅度之和与左心室前壁厚度的相关性60～79岁组最强(相关系数为0.48,P<0.01),80～89岁组二者相关性减弱(相关系数为0.23,P<0.05),而90～101岁组二者无相关性(相关系数为0.03,P>0.05).结论 心电图左心室肥厚诊断标准在90岁以下老年男性中具有可靠性.     

Electrocardiographic Markers of Late Sudden Death Risk in Postoperative Tetralogy of Fallot Children

Late Sudden Death Risk in Postoperative TOF. Following surgery for tetralogy of Fallot (TOP), children may develop late onset ventricular arrhythmias. Many patients have both depolarization and repolarization abnormalities, including right bundle branch block (RBBB) and QT prolongation. The goal of this study was to improve prospective risk-assessment screening for late onset sudden death. Resting ECG markers including QRS duration, QTc, JTc, and interlead QT and JT dispersion were statistically analyzed to identify those patients at risk for ventricular arrhythmias and sudden cardiac death. To determine predictive markers for future development of arrhythmia, we examined 101 resting ECGs in patients (age 12 ± 6 years) with postoperative TOF and RBBB, 14 of whom developed late ventricular tachycardia (VT) or sudden death. These ECGs were also compared with an additional control group of 1000 age- and gender-matched normal ECGs. The mean QRS (± SD) in the VT group was 0.18 ± 0.02 seconds versus 0.14 ± 0.02 seconds in the non-VT group (P < 0.01). QTc and JTc in the VT group was 0.53 ± 0.05 seconds and 0.33 ± 0.03 seconds compared with 0.50 ± 0.03 seconds and 0.32 ± 0.03 seconds in the non-VT group (P = NS). There was no increase in QT dispersion among TOF patients with VT or sudden death compared with control patients or TOF patients without VT, although JT dispersion was more common in the TOF groups. A prolonged QRS duration in postoperative TOF with RBBB is more predictive than QTc, JTc, or dispersion indexes for identifying vulnerability to ventricular arrhythmias in this population, while retaining high specificity. The combination of both QRS prolongation and increased JT dispersion had very good positive and negative predictive values. These results suggest that arrhythmogenesis in children following TOF surgery might involve depolarization in addition to repolarization abnormalities. Prospective identification of high-risk children may be accomplished using these ECG criteria.     

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。     

A study of the human heart as a multiple dipole source. IV. Left ventricular hypertrophy in the presence of right bundle branch block.

This report concerns the task of electrocardiographic (ECG) diagnosis and quantitation of left ventricular hypertrophy (LVH) in patients with right bundle branch block (RBBB). In 36 patients with RBBB the left ventricular mass (LVM) of each patient was independently known from quantitative biplane angiography. Two ECG techniques, standard 12-lead ECG and multiple dipole electrocardiography (MDECG), were evaluated. In diagnosing LVH, the best performance of the several standard ECG criteria was sensitivity = 29%, specificity = 100%, and that of the MDECG was sensitivity = 94%, specificity = 96%. In quantitating LVH, the standard ECG gave a correlation with LVM of r = 46% and a standard error of estimate of 98 g. The corresponding figures for the MDECG were r = 81% and the root mean square prediction error = 64 g. These results confirm other studies showing that the conventional ECG is of only marginal value in the task of diagnosing LVH in the presence of RBBB. In contrast, the MDECG performs well both in this task and that of quantitating LVH. The results provide further support of the accuracy of the model of the cardiac electrical generator and volume conductor used in the MDECG method.     

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.     

Safe right bundle branch block pattern during permanent right ventricular pacing

It is known that an electrocardiogram (ECG) after transvenous right ventricular (RV) pacing should yield left bundle branch block (LBBB) QRS patterns. When right bundle branch block (RBBB) pacing morphology appears in a patient with a permanent or temporary transvenous RV pacemaker, myocardial perforation or malposition of the pacing lead must be ruled out, even though the patient may be asymptomatic. We report a case of a 77-year-old man who underwent permanent transvenous VDD pacemaker implantation for symptomatic heart block. The postoperative ECG revealed a RBBB pacing configuration, but his chest X-ray and echocardiographic studies confirmed uncomplicated RV pacing. We review and discuss the literature concerning the differential diagnosis of such a safe RBBB ECG pattern.     

Left atrial abnormality by electrocardiogram predicts left ventricular hypertrophy by echocardiography in the presence of right bundle-branch block

Background: Left ventricular hypertrophy (LVH) on the electrocardiogram (ECG) may be masked in the presence of complete right bundle-branch block (RBBB). Left bundle-branch block on the ECG is associated with LVH at autopsy in 93% of hearts studied. However, RBBB does not predict LVH and the usual ECG criteria applied for LVH may not be reliable in the presence of RBBB. Hypothesis: The study was undertaken to evaluate left atrial (LA) abnormality as a criterion for the diagnosis of LVH in the presence of RBBB. Methods: Left atrial abnormality in the ECG was assessed by two independent observers as a criterion of LVH in the presence of RBBB in 100 patients, and data were compared with those of 50 patients without LA abnormality. Results: Left ventricular hypertrophy was confirmed by echocardiographic determination of left ventricular (LV) mass in both groups. Observers reliably differentiated between hy-pertrophied and normal-sized LV in the presence of RBBB by using LA abnormality as an ECG criterion when correlated with LV mass determined by echocardiography. Observer 1 correctly detected LVH in 88% and Observer 2 in 82% of patients. False positive diagnosis was made in 12 and 18% of patients by Observers 1 and 2, respectively. Observers' performance of recognition of LA abnormality in the present study was 94%. Results showed sensitivity of 76 and 70% and specificity of 84 and 92% for Observers 1 and 2, respectively. Left ventricular mass increased significantly and was diagnostic of LVH in 92% of patients with LA abnormality. Left ventricular mass was high in 84% of patients when corrected by body surface area. LVH in the presence of RBBB by the ECG was found in only seven patients (5%) when six commonly used conventional criteria of diagnosis of LVH by ECG were employed. Regression analysis found LA abnormality to be a strong independent predictor of increased LV mass. Multiple regression analysis revealed that age, body mass index, body surface area, and frontal axis are also significant predictors of LV mass. Conclusion: The results obtained by the correlation of LA abnormality by ECG and LVH by echocardiography conclude that LA abnormality by ECG was significantly diagnostic of LV hypertrophy in the presence of RBBB.     

Complete left branch block and electrocardiographic diagnosis of left ventricular hypertrophy

The electrocardiogrammes of 71 patients (39 men and 32 women) with transient or intermittent complete left bundle branch block (LBBB) were studied. Two tracings, one with and the other without LBBB were analysed in each case. The interval between the two recordings was less than 90 days in all cases (average 10 days). The diagnosis of left ventricular hypertrophy (LVH) was established from the ECG without LBBB. The sensitivity and specificity of the classical criteria or indices of LVA and of different associations of indices of LVH were assessed on the ECGs with LBBB. The best criteria of LVH in the presence of LBBB were the SV2 + RV6 greater than or equal to 32 mm (sensitivity 80%; specificity 81%), Sokolow's index greater than or equal to 33 mm (sensitivity 78%, specificity 81%); followed by SV1 greater than or equal to 23 mm (sensitivity 73%, specificity 86%), SV1 + SV2 + RV6 + RV7 greater than or equal to 65 mm (sensitivity 88%, specificity 63%), SV1 + SV2 greater than or equal to 54 mm (sensitivity 73%, specificity 74%). These six parameters allow correct diagnosis of LVH in 81%, 79%, 78%, 79% and 73% of cases, respectively. The SV1 + SV2 + RV5 + RV7 and the SV1 + SV2 + RV6 + RV7 greater than or equal to 65 mm indices are the most stable (same sensitivity and specificity for several consecutive threshold values, i.e. 62 to 67 mm and 64 to 66 mm respectively); the results obtained with these two indices are therefore more likely to be reproducible than those of the other indices as they seem less dependent on the sampling. The indices of LVH based on the QRS amplitude in the precordial leads remain valid in the presence of LBBB and are sufficiently reliable for the diagnosis of LVH to be clinically useful.     

Acute Effects of Single‐site Pacing from the Left and Right Ventricle on Ventricular Function and Ventricular–Ventricular Interactions in Children with Normal Hearts

Objective. We studied, as a physiological benchmark, acute effects of right ventricular (RV) apical, RV outflow, and left ventricular (LV) pacing in children with normal cardiac function on LV and RV function and ventricular–ventricular interactions. Design. The design of the study was a prospective, acute intervention. Setting. The study was conducted in a tertiary care electrophysiology laboratory. Population and Methods. Seven children (mean ± SD, 12 ± 4 years) were paced after accessory pathway ablation, at baseline (AOO), and with atrioventricular pacing (DOO) from the RV apex, RV outflow, and left ventricle. Outcome Measures. Right ventricular dP/dT_max and RV dP/dT_neg (high‐fidelity transducer‐tipped catheters, Millar Instruments, Houston, TX, USA), cardiac index (Fick), blood pressure, and QRS duration were measured at each pacing condition. Intra‐ and interventricular mechanical dyssynchrony, systolic‐ and diastolic peak tissue velocities, and isovolumic acceleration were recorded by tissue Doppler imaging at the lateral mitral, septal, and tricuspid annuli at each condition. Results at each pacing condition were compared by repeated‐measures analysis of variance. Results. Pacing prolonged QRS duration, causing electrical dyssynchrony (86 ± 19 ms [baseline], 141 ± 44 ms [RV apex], 121 ± 18 ms [RV outflow], and 136 ± 34 ms [LV], P < .01). Right ventricular outflow pacing caused LV intraventricular delay (63 ± 52 vs. 12 ± 7 ms, P < .05). Right ventricular apical pacing caused interventricular delay (61 ± 29 vs. 25 ± 18 ms, P < .05). There were no significant changes in blood pressure, cardiac index, RV dp/dT_max, RV dP/dT_neg, regional tissue velocities, or isovolumic acceleration during any of the pacing conditions, indicating preserved ventricular function and hemodynamics. No important ventricular–ventricular interactions were seen. Conclusions. In children with normal cardiac anatomy and function, single‐site RV apical, RV outflow, and LV pacing induce electromechanical dyssynchrony without significantly changing ventricular function or hemodynamics, or adversely affecting ventricular–ventricular interactions.     

Modified Cornell electrocardiographic criteria in the assessment of left ventricular hypertrophy geometry of patients with essential hypertension

To evaluate the value of modified Cornell electrocardiographic criteria in the assessment of left ventricular hypertrophy (LVH) for patients with essential hypertension. A total of 381 patients with essential hypertension diagnosed in our hospital were selected. Using the left ventricle (LV) geometric patterns classified by the American Society of Echocardiography (ASE), we examined the distribution of the modified Cornell criteria of Ravl + S_D (the deepest S wave in 12‐lead ECG) in different geometric patterns and analyzed the correlation of modified Cornell criteria with changes in the LV geometric patterns using multiple linear regression analysis. The distribution of modified Cornell criteria, Sokolow‐Lyon criteria (RV5/V6 + SV1), and Cornell criteria (Ravl + SV3) in gender‐specific hypertensive geometric patterns were significantly different (P ≤ .01 for all). The voltage of Ravl + S_D in male patients showed an increase trend in the normal geometry (NG), concentric remodeling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH) groups, and this increase trend was significantly in the unadjusted model and the adjusted model. The voltages of Ravl + SV3 and RV5/V6 + SV1 of male patients in CR, CH and RH groups showed a gradual increase trend, but the increase trend in CR group has no statistical significance compared to that in NG group (P ≥ .05). The voltages of Ravl + S_D, RV5/V6 + SV1, and Ravl + SV3 in female patients in CR, CH and EH groups showed a trend of increase after decrease in the adjusted model. In conclusion, the modified Cornell criteria could dynamically reflect left ventricular hypertensive geometry of male patients.     

Electrocardiographic Criteria of Left Ventricular Hypertrophy in Patients with Morbid Obesity

Background: Obesity is frequently accompanied by systemic hypertension complicated by left ventricular hypertrophy (LVH). Standard electrocardiography (ECG) is generally accepted screening tool for LVH in systemic hypertension. The aim was to assess currently used ECG criteria in the diagnosis of LVH in morbidly obese patients. Methods: Ninety‐five patients (80 women, 15 men) with body mass index ≥ 40 kg/m², prior to scheduled bariatric surgery were included into the study. All patients underwent standard ECG and transthoracic ECG for LVH assessment. Results: Echocardiographically LVH (>110 g/m² in women, and >132 g/m² in men) was diagnosed in 54 patients (56.8%). None of the ECG criteria showed satisfactory performance in the diagnosing echocardiographically confirmed LVH. Although, Receiving operating curves (ROC) analysis showed that only Romilht‐Estes score and Cornell index × QRS complex duration were characterized by area under curve >0.6 (0.662; 0.612, respectively),currently recommended values of both tests (Romilht‐Estes score and Cornell index × QRS duration 2436 mm · ms) showed very low sensitivity in morbidly obese patients (0% and 2%, respectively). Conclusions: Our study showed that none of voltage‐based ECG criteria are of value for LVH diagnosis in severely obese patients. Only Romhilt‐Estes scale and Cornell indices could be helpful for the identification of LVH in the group of patients with morbid obesity, but their value is far from being satisfactory. Ann Noninvasive Electrocardiol 2011;16(3):258–262     

Influence of serum potassium on the electrocardiographic pattern of left ventricular hypertrophy in primary hyperaldosteronism.

Only a few studies deal with electrocardiographic (ECG) signs of left ventricular hypertrophy (LVH) in patients with primary hyperaldosteronism, although it may be presumed that many factors such as arterial hypertension, hypokalemia, increased blood volume, and decreased activity of the renin-angiotensin system can modify LVH pattern in this entity. For that reason, we evaluated ECG signs of LVH in 55 patients with primary hyperaldosteronism hospitalized in our department from 1971 to 1990. These data were compared with age, serum potassium level, plasma renin activity (PRA) and-in 14 patients-with left ventricular mass, measured echocardiographically. We found inverse correlation between serum potassium concentration and the Sokolow-Lyon index: SV1 + RV5/6 (r = -0.47, p < 0.001). Among 24 patients with only abnormal QRS voltage, without ST-T changes suggestive of LVH, 19 (79.2%) had hypokalemia. In multivariate analysis, potassium concentration was the single independent predictor of an abnormal QRS voltage: -0.743, p = 0.01 vs. 0.153 (age), -0.337 (PRA) and 0.454 (LV mass). Our observations suggest that hypokalemia is an important factor influencing an amplitude of QRS complexes and may be responsible for false-positive LVH diagnosis.     

Effect of sex on informative power of various electrocardiographical criteria of left ventricular hypertrophy in patients with excessive body mass

Aim of the study was to analyze dependence of various voltage parameters of QRS complex on increase of left ventricular myocardial mass (LVMM) in samples of men and women with excessive body mass or obesity. We included data from 223 patients with excessive body mass and diagnosis of stage I - II arterial hypertension. ECG was registered in 12 standard leads. Left ventricular hypertrophy (LVH) was certified if according to echoCG data LVMM exceeded 125 g/m2 in men and 110 g/m2 in women. Depending on sex and presence of LVH all patients were divided into 4 groups: M1 (men with LVH, n=74), M2 (men without LVH, n=74), W1 (women with LVH, n=55), anb W2 (women without LVH, n=20). We analyzed amplitudes of all waves of the QRS complex as well as Sokolow-Lyons voltage parameters and the Cornell index. The following intergroup differences were most significant: between groups M1 and M2 - in amplitudes of S waves in chest leads V3, V4; between groups W1 and W2 - in amplitudes of R-waves in limb leads I and aVL, and amplitudes of S-waves in lead III. Increases of the Cornell voltage index were observed both in men and women with LVH. The following criteria had greatest sensitivity at 95% specificity: in men - SV4 > 1,1 mV (34%) and RaVL+SV3 > 2,3 mV (32%); in women - RaVL > 0,8 mV (56%) and RI+SIII > 1,5 mV (56%). Informative power of electrocardiographical diagnosis of LVH can be augmented by the use of different voltage criteria in groups of men and women. In men most informative are chest leads (SV1 - V3, RaVL) while in women - limb leads (RI, RaVL, and SIII). The use of combination parameters RaVL+SV3 > 2,3 mV (in men) and RI+SIII > 1,5 mV (in women) allows to augment sensitivity with unchanged specificity. In patients with excessive body mass voltage the Sokolow-Lyons criterion is not informative. Most significant component of the Cornell voltage criterion in groups of men with excessive body mass is amplitude of SV3, in groups of women - amplitude of RaVL.     

Electrovectorcardiographic diagnosis of left ventricular hypertrophy in complete left bundle-branch block

Diagnosis of left ventricular hypertrophy (LVH) in the presence of complete left bundle-branch block (CLBB) is difficult. The value of several electro-vectorcardiographic criteria were studied in a series of 71 patients with CLBB analyzed by echocardiography. Thirty nine of the patients (55%) had anatomical LVH defined as being a left ventricular weight (LVW) above 316 g. Twenty five of the 71 patients (35%) had dilated cardiomyopathy (dCMP). Of the hypervoltage indices, only the sum of RV6 + SV2 and the QRS spatial maximum vector (MAXQRSxyz) showed a significant difference between the group with LVH and the group without LVH. The duration of QRS and the average vector of spatial area (AQRSxyz) also differed significantly between the two groups and showed a good correlation with LVW. Of the various criteria for LVH, the best balance between sensitivity and specificity belonged to the criteria of duration of QRS greater than 150 msec and AQRSxyz greater than 140 mV.msec, with a merit ratio of 0.44 and a diagnostic accuracy of 72 per cent. In the dCMP subgroup, all the voltage and duration indices were significantly different between the two groups. The criterion AQRSxyz greater than 135 mV.msec obtained the best diagnostic score, with a sensitivity of 94 per cent, specificity of 100 per cent, and accuracy of 96 per cent. This parameter gave the best overall expression of the combination of hypervoltage and delay in ventricular depolarization produced both by hypertrophy/ventricular dilation and conduction disturbances.     

Diagnosis of myocardial infarction and ischemia in the setting of bundle branch block and cardiac pacing

The diagnosis of myocardial infarction (MI) in the presence of left bundle branch block (LBBB) or during ventricular pacing (VP) is challenging because of inherent changes in the sequence of ventricular depolarization and repolarization associated with both conditions. Although LBBB and right ventricular (RV) pacing may both produce abnormalities in the ECG, it is often possible to diagnose an acute MI (AMI) or an old MI based on selected morphologic changes. Primary ST-segment changes scoring 3 points or greater according to the Sgarbossa criteria are highly predictive of an AMI in patients with LBBB or RV pacing. The modified Sgarbossa criteria are useful for the diagnosis of AMI in patients with LBBB; however, these criteria have not yet been studied in the setting of RV pacing. Although changes of the QRS complex are not particularly sensitive for the diagnosis of an old MI in the setting of LBBB or RV pacing, the qR complex and Cabrera sign are highly specific for the presence of an old infarct. Diagnosing AMI in the setting of biventricular (BiV) pacing is challenging. To date there is minimal evidence suggesting that the traditional electrocardiographic criteria for diagnosis of AMI in bundle branch block may be applicable to patients with BiV pacing and positive QRS complexes on their ECG in lead V1. This report is a careful review of the electrocardiographic criteria facilitating the diagnosis of acute and remote MI in patients with LBBB and/or VP.     

右室心尖部起搏时体表心电图V1导联呈右束支阻滞图形分析

目的分析右室心尖部起搏患者V1导联呈现右束支阻滞图形的特点、出现的可能机制以及鉴别诊断方法。方法选取北京大学人民医院2005—2007年于右室心尖部植入起搏电极的患者,分析患者完全右室起搏时V1导联呈右束支阻滞图形患者的超声心动图、胸部X线等资料,并与同期V1导联呈左束支阻滞图形变化的右室起搏患者以及植入左室心外膜电极的患者的临床资料以及体表心电图特点进行对比。结果共有9例患者术后完全心室起搏时V1导联呈右束支阻滞图形,术后超声心动图以及胸部X线检查证实起搏电极均位于右心室,QRS波平均电轴为-61.7±15.6,与随机选取50例术后体表心电图呈左束支阻滞的右室电极植入患者心电图相比,QRS波电轴差异无统计学意义(P>0.05),与7例行左室心外膜起搏者QRS波电轴差异有统计学意义(P<0.05)。呈右束支阻滞者其肢体导联I、aVL导联QRS波均直立,与呈左束支阻滞患者相同,而左室心外膜起搏者其I、aVL导联QRS波为负向。结论当患者V1导联呈右束支阻滞形态时可通过I、aVL导联QRS波形态和QRS波电轴可以判断是否为右室起搏。     

Evaluation of electrocardiographic criteria for left ventricular hypertrophy based on anatomical comparison

The reliability of precordial electrocardiographic criteria for left ventricular hypertrophy (LVH) was evaluated by comparing it with the anatomical findings of 421 postmortem hearts examined by the chamber dissection technique. Of these 421 postmortem hearts, 136 without cardiovascular disease served as normal controls. The weights of the left ventricular free wall with interventricular septum (LV + S) and of the whole heart in normal controls were 153 +/- 36 grams (mean +/- SD) and 289 +/- 67 grams, respectively. Correlation coefficients between LV + S and whole heart were 0.89 for men and 0.90 for women. Anatomical LVH was defined as the weight of LV + S exceeding the average plus one standard deviation of that of a normal control heart. Anatomically established LVH was found in 99 (28%) of 353 cases having precordial electrocardiograms available for evaluation. The sensitivity, specificity, and predictive accuracy of electrocardiographic criteria for LVH were as follows: SV1 + RV5 greater than 3.5 mV, 56.6%, 76.0% and 47.9%; SV1 + RV5 greater than 4.0 mV, 45.5%, 87.4% and 58.4%; SV1 + RV5 greater than 5.0 mV, 21.2%, 94.5% and 60.0%; SV1 + RV5 greater than 3.5 mV with strain type ST-T, 35.4%, 93.3% and 67.3%; SV1 + RV5 greater than 4.0 mV with strain type ST-T, 29.3%, 94.9% and 69.0%; SV1 + RV5 greater than 5.0 mV with strain type ST-T, 14.1%, 98.0% and 73.7%; strain type ST-T, 36.4%, 92.5% and 65.5%; nonspecific ST-T, 26.3%, 76.4% and 30.2%; SV1 + RV5 greater than 3.5 mV with nonspecific ST-T, 12.1%, 93.3% and 41.4%; and right anteriorly directed T vector, 39.4%, 89.4% and 59.1%.(ABSTRACT TRUNCATED AT 250 WORDS)