Diagnostic accuracy of NT-proBNP compared with electrocardiography in detecting left ventricular hypertrophy of hypertensive origin

Electrocardiography (ECG) is the most widely used method for diagnosing left ventricular hypertrophy (LVH) in hypertensive patients. We assessed the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) determination compared with ECG for detecting LVH in 336 consecutive hypertensive patients with preserved systolic function. We found a significant correlation between NT-proBNP levels and left ventricular mass adjusted for body surface area (r = .41; P < .001). The area under the receiver operating characteristic curve was 0.75 (95% CI, 0.7-0.8). A cut-off of 74.2 pg/mL had a greater sensitivity than ECG (76.6% vs 25.5%; P < .001) and a higher negative predictive value (87.8% vs 76.6%; P < .001) in the identification of LVH. NT-proBNP determination may be a useful tool for LVH screening in hypertensive patients.Full English text available from: www.revespcardiol.org     

Myocardial perfusion SPECT in right bundle branch block and left anterior hemiblock

The aim of this study was to determine the diagnostic accuracy of myocardial perfusion SPECT (single photon emission computed tomography) with technetium labeling in patients with right bundle branch block (RBBB) and with left anterior hemiblock (LAH). One hundred seven patients (53 RBBB, 54 LAH) for whom coronary angiography results were available were selected. The gold standard for diagnosis was based on two coronary angiography criteria: a) stenosis equal to or greater than 50% in at least one coronary artery, and b) completely normal coronary angiography. The sensitivity of SPECT was approximately 90% in both RBBB and LAH. Specificity was 58% and 50%, respectively, for the first criterion, but was 85.7% and 87.5%, respectively, for the second criterion.     

完全性左束支传导阻滞SV3》SV2、RV6》RV5对左心室肥大的诊断价值

目的 探讨 左束 支 传导 阻滞 合并 左 心室 肥大 心 电图 诊断 价 值。 方法 对 照 分 析 ５０ 例左 束 支 传 导 阻 滞 合 并 左 心 室 肥 大（ 观 察 组 ）与 ４０ 例 单 纯 完 全 性 左 束 支 传 导 阻 滞（ 对 照 组 ）的 心 电图 。 结 果 观 察 组 Ｒ ＋ＳⅢ、ＳⅢ＞Ｒ 、Ｓｖ３＞Ｓｖ２、Ｒｖ６＞Ｒ ｖ５、Ｓｖ１＋Ｖ５、Ｓｖ３＋Ｒ ｖ６、Ｓｖ１＋Ｓｖ６ 值 与 对 照 组 相 比 差 异 有 Ⅰ Ⅱ非 常显 著 性意 义（Ｐ＜０．０１）。Ｓｖ３＞２．７ｍ Ｖ ，敏感 性 为 ８９．２％ ，准 确性为 ８５．３％ ，特异 性为 ８７．９％ ；其 次 Ｓｖ３＞Ｓｖ２，敏 感性 为 ５８．０％ ，准 确性 为 ６１．０％ ，特 异性 为 ７３．７％ ；　Ｓｖ３＋Ｒｖ６＞４．３ｍ Ｖ，敏 感性 为 ６８．８％ ，准 确 性 为 ６３．７％ 　，特 异 性 为 ７４．１％ 　；　Ｒ ｖ６＞Ｒ ｖ５，敏 感 性 为 ５２．４％ ，准 确 性 为 ６０．４％ ，特 异 性 为 ７０．６％ 。 结 论 Ｓｖ３＞２．７ｍ Ｖ 、Ｓｖ３＋Ｒ ｖ６＞４．３ｍ Ｖ 、Ｓｖ３＞Ｓｖ２、Ｒ ｖ６＞Ｒｖ５、ＱＲ Ｓ 时 间 ＞０．１５ｓ是 合 并左 心室 肥 大的 有效 心 电图 参数 。     

Left ventricular hypertrophy in left bundle branch block

The detection of left ventricular hypertrophy (LVH) in the presence of left bundle branch block (LBBB) remains a difficult clinical problem. Its prevalence and significance have not previously been studied in a group of living patients. M-mode echocardiography was utilized to determine the prevalence of anatomic LVH in 28 patients with LBBB. Various ECG and chest x-ray criteria as predictors of LVH were assessed. Anatomic LVH was present in 89% by echocardiography. A left atrial abnormality on ECG and a cardio-thoracic ratio greater than .50 were the best predictors of LVH. Hypertension and/or ischemic heart disease was present in 78.5% of the patients while only one patient was free of any evidence of cardiovascular disease.     

Electrocardiographic diagnosis of left ventricular hypertrophy in the presence of left bundle branch block

The electrocardiographic diagnosis of LVH in the presence of LBBB has previously been difficult. Thirty-seven patients with complete LBBB were identified and had echocardiography performed. Using an accepted echocardiographic formula, left ventricular mass was calculated. Twenty of the 37 patients (54%) were classified as having severe LVH. Multiple conventional ECG criteria for LVH were then evaluated. No QRS voltage criteria showed any difference between patients with and without LVH (P = NS). There was also no correlation between either QRS axis or left atrial enlargement and left ventricular mass (P = NS). However, the QRS duration was significantly longer in the patients with LVH (160 +/- 12 msec) than in the normal patients (148 +/- 11 msec) (P less than 0.001). The sensitivity, specificity, positive predictive value, and accuracy of several voltage criteria and QRS duration were examined. The best voltage criteria had a sensitivity of only 50% and a predictive value of 63%. However, a QRS duration greater than 155 msec had a sensitivity of 60% and a predictive value of 82%. This study demonstrates that the conventional QRS voltage criteria for LVH are not accurate in LBBB. A relationship exists between increasing QRS duration in LBBB and LVH; therefore, the relative probability adjectives: "consider," "possible," and "probable" should be used. QRS duration greater than 155 msec is predictive of LVH despite the presence of LBBB.     

The potential and reality of permanent his bundle pacing

Right ventricular apex pacing can have deleterious effects. Our aims were to investigate how many patients referred for permanent pacing were suitable candidates for permanent His bundle pacing, and to determine the proportion in whom such pacing was successful. All cases of suprahisian block and most cases of infrahisian block (71.4%) were corrected by temporary His bundle pacing. However, permanent His bundle pacing was achieved in only 55% of cases in which it was attempted, and in only 35.4% of all possible cases.     

Electrocardiographic diagnosis of left ventricular hypertrophy in the presence of complete right bundle branch block

There are few data evaluating electrocardiographic diagnosis of left ventricular (LV) hypertrophy in the presence of right bundle branch block (BBB). This study assesses the relative value of multiple electrocardiographic variables for detecting LV hypertrophy in patients with right BBB. LV hypertrophy was defined as LV mass greater than or equal to 215 g calculated from the Penn method using standard M-mode echo measurements. Sixty-two patients were evaluated (ages 41 to 94) and 35 had LV hypertrophy. None of the electrocardiographic criteria was sensitive; the best was mean QRS axis less than or equal to -30 degrees (sensitivity) 52%) and excessive negative P terminal force (sensitivity 28%). Several electrocardiographic variables were specific: Sokolow index greater than or equal to 35 mm (100%), RV5 or RV6 greater than or equal to 25 mm (96.3%), RI + SIII greater than or equal to 25 mm (92.6%) and intrinsicoid deflection greater than or equal to 0.05 seconds (88.5%). Conventional electrocardiographic criteria do not reliably detect LV hypertrophy in the presence of right BBB, but several criteria are relatively specific for LV hypertrophy.     

Electrocardiographic criteria of left ventricular hypertrophy in the presence of left bundle branch block

When left bundle branch block (LBBB) is present on the electrocardiogram, the diagnosis of left ventricular hypertrophy (LVH) may be difficult. The left ventricular mass in 70 patients with LBBB was estimated by echocardiography, and was compared to the QRS configuration on the electrocardiogram. We found that there was agreement between a monophasic R pattern in lead 1 or V6 (sensitivity 79.3%, 70.7%) and left ventricular hypertrophy. We suggest that a monophasic R pattern in L1 and V6 may provide a useful simple index of left ventricular hypertrophy in the presence of left bundle branch block.     

Electrocardiographic diagnosis of left ventricular hypertrophy accompanied by complete right bundle branch block]

The new electrocardiographic criteria for diagnosing left ventricular hypertrophy (LVH) were evaluated in patients with complete right bundle branch block (CRBBB) based on the relationships between left ventricular mass and multiple electrocardiographic variables obtained from 12-lead electrocardiograms. The subjects consisted of 88 patients with CRBBB, whose ages ranged from 18 to 86 years. Patients with histories of myocardial infarction, moderate to severe pericardial effusion and an undetermined axis were excluded from the study. LVH was defined as left ventricular mass (LVmass) > or = 215 g calculated from the Penn method using standard M-mode echo measurements. All electrocardiograms were interpreted by one investigator who had no knowledge of the echocardiographic results. Items calculated were the amplitude of Q, R, and S waves and their A/R, R/S, and S/A ratios, the mean frontal QRS axis, ventricular activation time in lead V5, the Morris' index, ST-T segment depression in leads V5,6, and negative U waves in leads V5,6. We selected 22 items for our criteria according to their sensitivity and specificity, and added to the 11 previously reported ones determined. LV wall thickness correlated best with R I (r = 0.57, p < 0.01), LV diastolic dimension with RV5 (r = 0.48, p < 0.01), and LV mass with R I+S III (r = 0.60, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Electrocardiographic diagnosis of left ventricular hypertrophy in the presence of left bundle branch block: a wasted effort

We assessed the reliability of multiple electrocardiographic variables for detecting left ventricular hypertrophy in 100 patients (aged 23 to 92 years, mean age 39 +/- 14) with complete left bundle branch block and different underlying cardiac diseases. Left ventricular hypertrophy, defined as an echocardiographically evaluated left ventricular mass greater than 241 g, was present in 66 of the 100 patients. The electrocardiographic parameters with the highest sensitivity were both the Cornell voltage criteria (RaVL + SV3 greater than 28 mm in men and greater than 20 mm in women) and the combination of criteria proposed by Kafka (any of these four indexes: RaVL greater than or equal to 11 mm, QRS axis -40 degrees or less, SV1 + RV5 or RV6 greater than or equal to 40 mm, SV2 greater than or equal to 30 mm and SV3 greater than or equal to 25 mm), with a sensitivity of 77%. Both criteria had a very low specificity (32 and 35%, respectively). The high specificities (greater than or equal to 88%) of several electrocardiographic criteria were accompanied by ineffective low sensitivities (less than 35%). Moreover, the cumulative parameters of Kafka and Cornell voltage criteria achieved a sensitivity of 84 and 89%, respectively, in hypertensive patients and in those with valvar diseases. None of the electrocardiographic indexes tested showed a significant difference in sensitivity when applied in categories of patients with left ventricular hypertrophy and different left ventricular geometry (cavity dilation or concentric hypertrophy). These data indicate that both conventional and recently proposed electrocardiographic criteria for left ventricular hypertrophy in the presence of left bundle branch block poorly recognize an augmented left ventricular mass.     

Electrocardiographic diagnosis of left ventricular hypertrophy in the presence of left bundle branch block: an echocardiographic study

This study tests the electrocardiographic diagnosis of left ventricular (LV) hypertrophy in the presence of left bundle branch block (BBB). The LV mass of 125 patients with left BBB was estimated by echocardiography. M-mode echocardiography was technically adequate in 80% of patients. LV mass was calculated using previously validated M-mode formulas and then indexed to body surface area. The known shifts in the QRS voltage and axis with the onset of left BBB led to the selection of 4 electrocardiographic parameters for the diagnosis of LV hypertrophy: R in aVL 11 or more; QRS axis -40 degrees or less (or SII greater than RII); SV1 + RV5 to RV6 40 or more; SV2 30 or more and SV3 25 or more; these parameters were used in cumulative fashion. This cumulative approach was superior to using single conventional criterion such as the SV1 + RV5 or RV6. When LV hypertrophy was defined as an M-mode index of at least 115 g/m2, the sensitivity was 75% and specificity 90%. Using an M-mode mass of at least 215 g as the standard, the sensitivity was 73% and the specificity 66%. LV hypertrophy can be diagnosed by electrocardiographic criteria in the presence of left BBB at least as reliably as in normal conduction.     

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.     

胸导联低一肋QRS形态对左束支传导阻滞合并左心室肥大的诊断价值

目的探讨胸导联低一肋间（V1-V6）心电图QRS形态对完全性左束支传导阻滞合并左心室肥大的诊断价值。方法对心电图示完全性左束支传导阻滞患者加作V1-V6心电图，依据超声心动描记术诊断分为左束支传导阻滞合并左心室肥大（观察组，n=57）与单纯完全性左束支传导阻滞组（对照组，n=49），分析心电图各项指标。结果观察组V5或V6呈Rs、RS、rs、或rsr′型以及V5呈Rs、rs、rS、rSr′型可支持左心室肥大的诊断（P〈0．05）；与Rv6＋SV2≥4，5mV、SV2〉3.5mV和QRS时间≥0．15s比较，Rv6≥Rv、5Rv6≥Rv5、的敏感性较高（P〈0．05）；与Rv6＋Sv2≥4．5mV及Sv2〉3．5mV比较，Rv6≥Rv6和Rv5≥Rv5特异性较高（P〈0．05或P〈0．01）。结论V1～V6QRS形态的特征变化可能提高对左心室肥大诊断的敏感性、特异性及准确性。     

Electrocardiographic criteria for diagnosis of left ventricular hypertrophy in the presence of complete right bundle branch block

The usual electrocardiographic criteria recommended for left ventricular (LV) hypertrophy may be unreliable in the presence of complete right bundle branch block (BBB). Thirty-six standard electrocardiographic criteria for LV hypertrophy were evaluated in 100 patients (mean age +/- standard deviation 67 +/- 11 years) with right BBB and technically satisfactory echocardiograms. Eight additional electrocardiographic criteria derived from this study also were evaluated. LV mass index was determined from the echocardiogram using the Penn method. LV hypertrophy defined as LV mass index greater than 132 g/m2 in men and 109 g/m2 in women was present in 56 of the 100 patients. Electrocardiographic criteria with the highest sensitivity were SIII + (R + S) maximal precordial lead greater than or equal to 30 mm (sensitivity 68%), specificity 66%), left axis deviation of -30 degrees to -90 degrees (sensitivity 59%, specificity 71%) and combination of left axis deviation and SIII + (R + S) maximal precordial lead greater than or equal to 30 mm (sensitivity 52%, specificity 84%). The electrocardiographic criteria with the highest sensitivity and specificity greater than 90% were left axis deviation of -30 degrees to -90 degrees and SV1 greater than 2 mm (sensitivity 34%), point-score system, RaVL greater than 12 mm and RI + SIII greater than 25 mm (each with a sensitivity of 27%). In general, limb lead voltage criteria such as RaVL greater than 11 mm (sensitivity 29%, specificity 86%) had higher sensitivities than criteria using right precordial lead S-wave voltage criteria such as SV1 + RV5, V6 greater than 35 mm (sensitivity 2%, specificity 100%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Usefulness of left atrial abnormality for predicting left ventricular hypertrophy in the presence of left bundle branch block

The objective of this study was to identify left atrial (LA) abnormality on the electrocardiogram and other related variables as predictors of left ventricular (LV) hypertrophy in the presence of left bundle branch block (LBBB). In the presence of complete LBBB, the diagnosis of electrocardiographic abnormalities is problematic and that of LV hypertrophy remains difficult. The usual electrocardiographic criteria applied for the diagnosis of LV hypertrophy may not be reliable in the presence of LBBB. Therefore, noninvasive criteria will help physicians diagnose LV hypertrophy with electrocardiography. LA abnormality on the electrocardiogram was assessed by 2 independent observers as predictor of LV hypertrophy in the presence of LBBB in 120 patients, and data were compared with those of 100 patients without LA abnormality. LV mass was calculated from echocardiographic data. Besides LA abnormality, the other variables studied for prediction of LV hypertrophy were gender, age, body surface area, body mass index, frontal axis, and QrS duration. Of the 6 criteria analyzed, the P terminal force was found to be the most common and consistent criterion to detect LA abnormality. LV hypertrophy was confirmed by echocardiographic determination of LV mass in both groups. Observers reliably differentiated between the hypertrophied and normal-sized left ventricle in the presence of LBBB by correlating LA abnormality with LV mass determined by echocardiography. Observer 1 detected LA abnormality in 89% and observer 2 in 84% of patients. False-positive results were present in 11% and 16%. The observer's recognition of LA abnormality in the present study was 91%. The 2 observers showed a sensitivity of 81% and 79% and a specificity of 91% and 88%, respectively, when diagnosis of LV hypertrophy was determined. LV mass increased significantly and was diagnostic of LV hypertrophy in 92% of patients with LA abnormality. In the remaining 11 patients (8%), the LA abnormality was of marginal abnormal magnitude. Each 0.01-mV/s increase in LA abnormality gave an increase of 30 g of LV mass. LV mass was increased in 86% of patients when corrected by body surface area. LV hypertrophy in the presence of LBBB on electrocardiography was found in only 13 patients (10%) when the 6 frequently used conventional criteria for diagnosis of LV hypertrophy by electrocardiography were used. Regression analysis revealed LA abnormality to be a strong independent predictor of increased LV mass. Multivariate analysis also revealed age, body mass index, body surface area, frontal axis, and QrS duration to be significant predictors of LV mass. This noninvasive study correlates LA abnormality by electrocardiogram and LV hypertrophy with echocardiography to conclude that LA abnormality was significantly diagnostic of LV hypertrophy in the presence of LBBB. Age, body mass index, body surface area, frontal axis, and QrS duration were also significant predictors of LV mass.     

Body surface mapping criteria for diagnosis of left ventricular hypertrophy associated with complete right bundle branch block

The standard electrocardiographic (ECG) criteria for left ventricular hypertrophy are unreliable in patients with complete right bundle branch block. This study was undertaken to formulate criteria for diagnosing these patients by using body surface mapping. The echocardiographic left ventricular mass was calculated by the Penn method from M-mode measurements. Of 56 patients, 27 were defined as having left ventricular hypertrophy with a left ventricular mass of 215 g or more. Isopotential and isointegral maps of the QRS complex were observed. The QRS isointegral maps were separated into two parts at the end of the downstroke of the initial R wave of vector spatial magnitude. The body surface mapping criteria with the highest sensitivity were EPmax (maximum of early part of the QRS) 45 μV·s or greater (sensitivity 93%, specificity 90%), EPmax/d (EPmax averaged by EP duration) 0.8 mV or greater (sensitivity 93%, specificity 97%), and Max (initial maximum) 2.2 mV or greater (sensitivity 89%, specificity 90%). These results suggest that body surface mapping is a useful technique in diagnosing patients with left ventricular hypertrophy and right bundle branch block.     

Vectorcardiographic diagnosis of right ventricular hypertrophy in the presence of right bundle branch block in young subjects.

Two groups of young patients, one with right bundle branch block complicated by right ventricular hypertrophy due to congenital heart disease, the other with right bundle branch block and no right ventricular hypertrophy, could be separated on the basis of a few quantitative vectorcardiographic and electrocardiographic criteria. Vectorcardiographic criteria proved better than electrocardiographic criteria in detecting right ventricular hypertropy in individual patients with complete right bundle branch block. Criteria based on the configuration of the QRS loop were also specific but much less sensitive for the diagnosis of this association. In a similar population, that is, young patients with postoperative right bundle branch block, the existence of a residual right ventricular overload would be strongly suggested by the presence of any one of the following criteria: (1) a clockwise rotation of the QRS loop in the horizontal plane, (2) a ratio of the magnitude of the R wave to that of the S wave (R/S ratio) in lead X at less than 2.0, (3) a mean QRS vector in lead X more negative than--10 mv.msec, or (4) a maximal QRS vector located between 90 degrees and 270 degrees in the horizontal plane. In contrast, an R/S ratio in lead X that was equal or superior to 2.0 or an azimuth angle of the mean spatial QRS vector that was not between 90 degrees and 180 degrees would indicate that the right ventricular conduction defect is probably uncomplicated.