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.     

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 。     

Electrocardiographic strain pattern and left ventricular diastolic function in hypertensive patients with left ventricular hypertrophy: the LIFE study

BACKGROUND: Whether the typical electrocardiographic (ECG) strain pattern (Strain, in leads V5 and/or V6), which is associated with left ventricular hypertrophy (LVH) and LV systolic dysfunction, is independently associated with LV diastolic dysfunction is unknown. METHODS: The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study enrolled hypertensive patients with ECG-LVH, of whom 10% underwent Doppler echocardiography. LV diastolic function measures included peak mitral E and A wave velocities and their ratio (E/A); E wave deceleration time (EDT); atrial filling fraction (AFF); and isovolumic relaxation time (IVRT). Normal filling pattern was defined by E/A < 1 with EDT >or= 150 and or=60 ms; abnormal relaxation by E/A < 1 with EDT > 250 ms or IVRT > 100 ms; pseudonormal filling pattern by E/A >or= 1 associated with IVRT > 100 ms or EDT > 250 ms; restrictive pattern by E/A >or= 1 with IVRT < 100 ms and EDT < 250 ms. A combined index of LV systolic-diastolic function was also computed (isovolumic time/ejection time, modified myocardial performance index). Of LIFE echo substudy participants with all needed ECG and Doppler data (n = 791), 110 (14%) had Strain. RESULTS: Strain was associated with male gender, African-American race, diabetes, history of coronary heart disease (CHD), higher systolic blood pressure (BP), LV mass and relative wall thickness, and higher prevalences of echo-LV hypertrophy and wall motion abnormalities, and with slower heart rate (all P < 0.05). Age, diastolic BP and LV ejection fraction were similar in patients with or without Strain. Diastolic parameters, and prevalences of different LV filling patterns, did not differ significantly between patients with versus those without Strain (all P > 0.1), but modified myocardial performance index was higher with Strain (P < 0.05). Findings were consistent in multivariate analyses. The association of Strain with higher modified myocardial performance index was no longer statistically significant after accounting for LV systolic function and wall motion abnormalities. CONCLUSIONS: In hypertensive patients with ECG-LVH, the ECG Strain pattern did not identify independently those with more severe LV diastolic abnormalities.     

Microalbuminuria in hypertensive patients with electrocardiographic left ventricular hypertrophy: the LIFE study

OBJECTIVES : Left ventricular hypertrophy and albuminuria have both been shown to predict increased cardiovascular morbidity and mortality. However, the relationship between these markers of cardiac and renal glomerular damage has not been evaluated in a large hypertensive population with target organ damage. The present study was undertaken to determine whether albuminuria is associated with persistent electrocardiographic (ECG) left ventricular hypertrophy, independent of established risk factors for cardiac hypertrophy, in a large hypertensive population with left ventricular hypertrophy who were free of overt renal failure. METHODS : Patients with stage II-III hypertension were enrolled in the study if they had left ventricular hypertrophy on a screening ECG by Cornell voltage-duration product and/or Sokolow-Lyon voltage criteria, and clinic blood pressures between 160 and 200/95-115 mmHg and plasma creatinine < 160 mmol/l. A second ECG and morning spot urine were obtained after 14 days of placebo treatment. Renal glomerular permeability was evaluated by urine albumin/creatinine (UACR, mg/mmol). Microalbuminuria was present if UACR > 3.5 mg/mmol and macroalbuminuria if UACR > 35 mg/mmol. RESULTS : The mean age of the 8029 patients was 66 years, 54% were women. Microalbuminuria was found in 23% and macroalbuminuria in 4% of patients. Microalbuminuria was more prevalent in patients of African American (35%), Hispanic (37%) and Asian (36%) ethnicity, heavy smokers (32%), diabetics (36%) and in patients with ECG left ventricular hypertrophy by both ECG-criteria (29%). Urine albumin/creatinine was positively related to Sokolow-Lyon voltage criteria and Cornell voltage-duration product criteria. In multiple regression analysis, higher UACR was independently associated with older age, diabetes, higher blood pressure, serum creatinine, smoking and left ventricular hypertrophy. Patients smoking > 20 cigarettes/day had a 1.6-fold higher prevalence of microalbuminuria and a 3.7-fold higher prevalence of macroalbuminuria than never-smokers. ECG left ventricular hypertrophy by Cornell voltage-duration product or Sokolow-Lyon criteria was associated with a 1.6-fold increased prevalence of microalbuminuria and a 2.6-fold increase risk of macroalbuminuria compared to no left ventricular hypertrophy on the second ECG. CONCLUSIONS : In patients with moderately severe hypertension, left ventricular hypertrophy on two consecutive ECGs is associated with increased prevalences of micro- and macroalbuminuria compared to patients without persistent ECG left ventricular hypertrophy. High albumin excretion was related to left ventricular hypertrophy independent of age, blood pressure, diabetes, race, serum creatinine or smoking, suggesting parallel cardiac damage and albuminuria.     

Impact of valvular regurgitation on left ventricular geometry and function in hypertensive patients with left ventricular hypertrophy: the LIFE study

Mild-to-moderate aortic and mitral regurgitation are frequently detected by echocardiogram in asymptomatic hypertensive patients. Our goal was to assess the prevalence and impact of mild-to-moderate mitral and/or aortic regurgitation on left ventricular (LV) structure and function in patients with hypertension and LV hypertrophy (LVH). Hypertensive patients with ECG LVH enrolled in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography substudy were evaluated. Among 939 patients with needed LV measurements and Doppler data, 242 had mild (1+) valvular regurgitation, and 51 patients had moderate (2+ or 3+) regurgitation of one or both valves. In analyses adjusting for gender, patients with mild mitral and/or aortic regurgitation had larger LV internal dimensions (5.25 vs 5.33 cm, P<0.05), higher LV mass indexed for body surface area (122 vs 125 g/m(2), P<0.05) or height(2.7) (55.4 vs 57.3, P<0.05), and larger left atrial diameter. Patients with moderate regurgitation of one or both valves had larger LV chambers (5.25 vs 5.9 cm, P<0.001), greater mean LV mass (232 vs 248 g, P<0.001) and LV mass indexed for body surface area or height(2.7), and higher Doppler stroke volume. Patients with moderate valvular regurgitation also had a higher prevalence of LVH due to an increased prevalence of eccentric LVH. There were no differences among groups defined by the presence and severity of valvular regurgitation in cardiac output, total peripheral resistance, or pulse pressure/stroke volume, indicating that the observed inter-group differences in LV geometry were not due to differences in the haemodynamic severity of hypertension. Hypertensive patients with mild-to-moderate mitral or aortic valvular insufficiency have additional LV structural and functional changes that may affect prognosis.     

Gender differences in systolic left ventricular function in hypertensive patients with electrocardiographic left ventricular hypertrophy (the LIFE study)

Echocardiography was performed in 944 untreated hypertensive patients (391 women and 553 men, mean age 66 years) who had electrocardiographic left ventricular (LV) hypertrophy at baseline in the Losartan Intervention For End point reduction in hypertension (LIFE) study to evaluate gender-associated differences in systolic LV function. Women had significantly lower diastolic blood pressure (175/97 vs 173/99 mm Hg) and body surface area and a higher body mass index (all p < 0.01). Women also had higher LV ejection fraction (EF), endocardial and midwall fractional shortening (63% vs 60%, 35% and 33%, and 16% vs 15%, respectively, all p < 0.01), higher stress-corrected midwall fractional shortening (98% vs 96%, p < 0.05), and lower circumferential end-systolic wall stress (178 vs 187 kdynes/cm(2), p < 0.01). There was no difference in age or LV mass indexed for height(2.7), but relative wall thickness was higher in women (0.42 vs 0.41, p < 0.05). In multiple regression analyses: (1) EF and endocardial fractional shortening were 2% to 3% higher in women than men, independent of the effects of LV stress, body mass index, and height (multiple r = 0.77 and 0.75, respectively, gender p < 0.02 in both models); (2) midwall fractional shortening was 0.5% higher in women, independent of the effects of age, body mass index, circumferential end-systolic stress, and absence of diabetes (multiple r = 0.36, p = 0.014 for gender); and (3) stress-corrected LV midwall fractional shortening was 2% higher (p = 0.004) in women, independent of the effects of age, height, heart rate, body mass index, and diabetes (multiple r = 0.33). Thus, female gender is an independent predictor of higher systolic LV function in hypertensive patients with electrocardiographic LV hypertrophy.     

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.     

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 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.     

Left bundle branch block and cardiovascular morbidity and mortality in hypertensive patients with left ventricular hypertrophy: the Losartan Intervention For Endpoint Reduction in Hypertension study

BACKGROUND: Whether left bundle branch block is associated with cardiovascular events in hypertension with electrocardiographic left ventricular hypertrophy is unknown. METHODS: Hypertensive patients with electrocardiographic-left ventricular hypertrophy were randomized to losartan-based or atenolol-based treatment and followed for 4.8 years in the losartan intervention for endpoint reduction in hypertension study. Cox regression models controlling for significant covariates assessed the association of left bundle branch block with cardiovascular events. RESULTS: At baseline, 564 patients had left bundle branch block and 8567 patients did not. Left bundle branch block was associated with higher heart rate, electrocardiographic-left ventricular hypertrophy, and prior cardiovascular disease (all P < 0.005). In univariate Cox regression analysis, left bundle branch block was not associated with the composite endpoint, stroke, or myocardial infarction (all P > 0.05), and was associated with cardiovascular (8.3 versus 4.5%, P < 0.001) and all-cause mortality (12.1 versus 8.6%, P < 0.005). After adjusting for significant covariates Cox regression analyses showed that left bundle branch block was independently associated with 1.6-fold more cardiovascular death (95% confidence interval 1.12-2.27, P < 0.05), 1.7 fold more hospitalization for heart failure (95% confidence interval 1.15-2.56, P < 0.01), 3.5 fold more cardiovascular death within 1 h (95% confidence interval 1.89-6.63, P < 0.001), and 3.4 fold more cardiovascular death within 24 h (95% confidence interval 1.83-6.35, P < 0.001). CONCLUSION: In hypertension with electrocardiographic-left ventricular hypertrophy, left bundle branch block identifies patients at increased risk of cardiovascular mortality, sudden cardiovascular death, and heart failure.     

Left atrial systolic force in hypertensive patients with left ventricular hypertrophy: the LIFE study

In hypertensive patients without prevalent cardiovascular disease, enhanced left atrial systolic force is associated with left ventricular hypertrophy and increased preload. It also predicts cardiovascular events in a population with high prevalence of obesity. Relations between left atrial systolic force and left ventricular geometry and function have not been investigated in high-risk hypertrophic hypertensive patients. Participants in the Losartan Intervention For Endpoint reduction in hypertension echocardiography substudy without prevalent cardiovascular disease or atrial fibrillation (n = 567) underwent standard Doppler echocardiography. Left atrial systolic force was obtained from the mitral orifice area and Doppler mitral peak A velocity. Patients were divided into groups with normal or increased left atrial systolic force (>14.33 kdyn). Left atrial systolic force was high in 297 patients (52.3%), who were older and had higher body mass index and heart rate (all P < 0.01) but similar systolic and diastolic blood pressure, in comparison with patients with normal left atrial systolic force. After controlling for confounders, increased left atrial systolic force was associated with larger left ventricular diameter and higher left ventricular mass index (both P < 0.01). Prevalence of left ventricular hypertrophy was greater (84 vs. 64%; P < 0.001). Participants with increased left atrial systolic force exhibited normal ejection fraction; higher stroke volume, cardiac output, transmitral peak E velocities and peak A velocities; and lower E/A ratio (all P < 0.01). Enhanced left atrial systolic force identifies hypertensive patients with greater left ventricular mass and prevalence of left ventricular hypertrophy, but normal left ventricular chamber systolic function with increased transmitral flow gradient occurring during early filling, consistent with increased preload.     

Cardiovascular risk reduction in hypertensive black patients with left ventricular hypertrophy: the LIFE study

OBJECTIVES: We report on a subanalysis of the effects of losartan and atenolol on cardiovascular events in black patients in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study. BACKGROUND: The LIFE study compared losartan-based to atenolol-based therapy in 9,193 hypertensive patients with left ventricular hypertrophy (LVH). Overall, the risk of the primary composite end point (cardiovascular death, stroke, myocardial infarction) was reduced by 13% (p = 0.021) with losartan, with similar blood pressure (BP) reduction in both treatment groups. There was a suggestion of interaction between ethnic background and treatment (p = 0.057). METHODS: Exploratory analyses were performed that placed LIFE study patients into black (n = 533) and non-black (n = 8,660) categories, overall, and in the U.S. (African American [n = 523]; non-black [n = 1,184]). RESULTS: A significant interaction existed between the dichotomized groups (black/non-black) and treatment (p = 0.005); a test for qualitative interaction was also significant (p = 0.016). The hazard ratio (losartan relative to atenolol) for the primary end point favored atenolol in black patients (1.666 [95% confidence interval (CI) 1.043 to 2.661]; p = 0.033) and favored losartan in non-blacks (0.829 [95% CI 0.733 to 0.938]; p = 0.003). In black patients, BP reduction was similar in both groups, and regression of electrocardiographic-LVH was greater with losartan. CONCLUSIONS: Results of the subanalysis are sufficient to generate the hypothesis that black patients with hypertension and LVH might not respond as favorably to losartan-based treatment as non-black patients with respect to cardiovascular outcomes, and do not support a recommendation for losartan as a first-line treatment for this purpose. The subanalysis is limited by the relatively small number of events.     

Telomere length and cardiovascular risk in hypertensive patients with left ventricular hypertrophy: the LIFE study

Short telomeres are associated with aging and age-related diseases. Our aim was to determine whether short leukocyte telomere length is associated with risk factors and cardiovascular diseases in a high-risk hypertensive population. We measured leukocyte telomere lengths at recruitment in 1271 subjects with hypertension and left ventricular hypertrophy (LVH) participating in the Lifestyle Interventions and Independence for Elders (LIFE) study. At baseline, short mean telomere length was associated with coronary artery disease in males (odds ratio (OR) 0.61, 95% confidence interval (CI) 0.39-0.95), and transient ischemic attack in females (OR 0.62 95% CI 0.39-0.99). Proportion of short telomeres (shorter than 5?kb) was associated with Framingham risk score (r=0.07, P<0.05), cerebrovascular disease (OR 1.18, 95% CI 1.01-1.15) and type 2 diabetes in men (OR 1.07, 95% CI 1.02-1.11). During follow-up, proportion of short telomeres was associated with combined cardiovascular mortality, stroke or angina pectoris (hazard ratio 1.04, 95% CI 1.01-1.07). Telomere length was not associated with smoking, body mass index, pulse pressure or self-reported use of alcohol. Our data suggest that reduced leukocyte telomere length is associated with cardiovascular risk factors and diseases as well as type 2 diabetes, and is a predictor of cardiovascular disease in elderly patients with hypertension and LVH.     

Assessment of left ventricular function from the electrocardiogram in left bundle branch block

The QRS duration, maximum right precordial S amplitude, sum of amplitudes of the maximum right precordial S and T wave and T wave polarity in lead I have been analyzed in order to identify electrocardiographic predictors of left ventricular end-diastolic volume index and ejection fraction in 165 patients with complete left bundle branch block and various forms of heart disease. Multivariate analysis selected the duration, maximal amplitude of the S wave and polarity of the T wave in decreasing order of discriminatory power, which correctly identify 76.6% of the patients with a normal end-diastolic volume index less than or equal to 90 ml/m2 and a normal ejection fraction greater than or equal to 60% (n = 64) and 73.3% of those with an end-diastolic volume index greater than 90 ml/m2 or an ejection fraction less than 60% (n = 101). The comparisons of the QRS duration with the end-diastolic volume index and the ejection fraction give the best single correlations: r = 0.57 and -0.63, respectively. Multiple correlations lead to no substantial improvement of the r values: 0.06 and -0.65, respectively. A QRS duration less than 140 msec is almost always predictive of the presence of a normal end-diastolic volume index and a normal ejection fraction (sensitivity 100%, specificity 91.9%, positive predictive value 73.3%). A QRS duration greater than 170 msec is most accurate in predicting depressed left ventricular ejection fraction less than 55% (sensitivity 36.5%, specificity 98%, positive predictive value 92%). Thus, only the QRS duration provides a useful reference and guide for the evaluation of left ventricular function in the presence of left bundle branch block.     

Echocardiographic left ventricular geometry in hypertensive patients with electrocardiographic left ventricular hypertrophy: The LIFE Study

Aim: To assess the prevalence of echocardiographic left ventricular hypertrophy (LVH) and concentric remodeling in hypertensive patients with electrocardiographic (ECG)-LVH and to estimate the costeffectiveness of echocardiography and ECG for detection of LVH.Design: Echocardiographic LV measurements and the prevalence of abnormal LV geometric patterns were compared between 964 hypertensive patients with ECG-LVH (Cornell voltage-duration product > 2440 and/or SV₁     

Correlation between interventricular septal motion and left ventricular systolic-diastolic function in patients with left bundle branch block

The echocardiographic correlation between abnormal interventricular septal motion including systolic paradoxical, flat motion and early diastolic notch and ejection fraction, mean ventricular circumferential fiber shortening and early diastolic mitral filling velocity was studied in 46 patients with complete left bundle branch block. Systolic normal interventricular septal motion was used as the control. Ejection fraction was significantly smaller in the paradoxical(0.44 +/- 0.13, p < 0.02) and flat motion groups(0.38 +/- 0.09, p < 0.001) than in the normal group(0.54 +/- 0.1). Mean ventricular circumferential fiber shortening was significantly smaller in the flat motion group than in the normal group(0.72 +/- 0.19 vs 0.99 +/- 0.23 circ/sec, p < 0.002). The size of the notch was significantly smaller in the flat motion group than in the normal group (2.3 +/- 0.2 vs 4.8 +/- 0.8 mm, p < 0.0001). The deceleration rate of the notch was significantly slower in the paradoxical and flat motion groups than in the normal group(37.3 +/- 12.2, 31.3 +/- 8.1 vs 69.1 +/- 2.5 cm/sec, p < 0.0001). Early diastolic mitral filling velocity was slower in the flat motion group than in the other 2 groups. In conclusion, systolic flat interventricular septal motion showed more severe disturbances of left ventricular systolic and diastolic function than paradoxical interventricular septal motion in patients with complete left bundle branch block.