十二导联心电图QRS时间-电压面积对诊断左室肥厚价值的研究

目的评价十二导联心电图QRS时间-电压面积诊断左室肥厚的价值.方法选择147例高血压病或有瓣膜反流性心脏病引起的左室肥厚病人以及271例无左室肥厚的对照者进行心电图和超声心动图检查,计算Sokolow-Lyon 和十二导联总和两种标准的单纯电压、电压-时间乘积和时间-电压面积数值.结果十二导联时间-电压面积总和标准和Sokolow-Lyon时间-电压面积标准诊断左室肥厚的敏感性(75.5%和64.6%)明显高于十二导联电压-时间乘积标准和Sokolow-Lyon电压-时间乘积标准(54.4%和53.7%),也高于十二导联电压总和标准和Sokolow-Lyon电压标准(45.6%和42.9%);时间-电压面积与左室重量指数(LVMI) 呈高度相关,电压-时间乘积和单纯电压与LVMI呈中度相关.结论时间-电压面积标准明显提高了十二导联心电图诊断左室肥厚的敏感性,它有希望成为心电图诊断左室肥厚的新指标.     

左心室肥厚心电图诊断标准分析

目的:对比左心室肥厚心电图诊断标准的敏感性和特异性,以评价不同标准的诊断价值.方法:分析364例原发性高血压患者的超声心动图及心电图检查结果.以超声心动图对患者左心室肥厚情况的检查结果为参照,求得不同心电图标准(Sokolow-Lyon标准、Comell标准、Romhilt-Estes评分、Framingham标准及Perugia标准)诊断左心室肥厚的敏感性和特异性.结果:5项心电图诊断标准的敏感性均＜50%;而特异性较高,除Perugia标准外,余4项标准均＞90%.Perugia标准的敏感性最高41%,特异性低89%;Sokolow-Lyon标准的敏感性22%及特异性93%均较低.结论:心电图诊断左心室肥厚的特异性高、敏感性稍差.Perugia标准是Comdl标准、左心室劳损改变、Romhilt-Estes评分等标准有机的结合,因此提高了心电图诊断的敏感性,而特异性未受到明显影响.     

高血压左室肥厚与Cornell电压标准

高血压左室肥厚（LVH）的诊断目前主要依靠心电图（ECG）和超声心动图（UCG）检查。利用超声心动图检测左室质量指数（LVMI），能准确地反映LVH时的心脏变化，成为临床评价LVH的可靠指标。心电图是心脏常用的检查方法之一，但传统的ECG．LVH诊断敏感性仅为UCG-LVH的1／7～1／10，难以满足临床所需。美国Comell医学中心推出的心电图Comell电压标准（RaVL＋Sv3），国外通过临床试验，已显示出其对LVH诊断的高效关系。     

多项心电图电压标准与高血压左室构型相关性的研究

目的探讨多项心电图电压标准在高血压左室构型中的表现。方法研究Comell、Sokolow—Lyon、Gubner—Ungerleider、∑QRS指数与高血压左室构型相关性,并比较四种电压标准在异常左室构型的敏感性、特异性。结果①Sokolow—Lyon指数在向心性重构组,向心性肥厚组增高;②∑QRS指数：异常左室构型组均增高;③Comell、Gubner—Ungerleider指数仅在向心性肥厚组增高。另一方面：①向心性重构组：Sokolow—Lyon指数、∑QRs指数增高;②向心性肥厚组：四种电压标准均增高;③离心性肥厚组：仅∑QRs指数增高。结论∑QRS指数对高血压异常左室构型有着高度敏感性,而Comell与Gubner—Ungerleider指数有着高度的特异性。四种电压标准在不同的左室构型有着相应的改变。     

高血压患者心电图SD波在诊断左心室肥厚中的价值

目的测试一种新的心电图诊断标准,提高诊断原发性高血压病合并左心室肥厚的准确性。方法以美国超声心动图学会对左心室质量测量作为标准,选取高血压病(HBP)合并左心室肥厚(LVH)患者129例,同期根据年龄、性别匹配高血压左心室正常组(109名)。同步记录12导联心电图,选取所有心电图导联中最深S波(S_D)为研究对象,与采用目前公认的LVH心电图标准Cornell和Sokolow-Lyon进行比较,计算心电图相关指标判断HBP合并LVH的ROC曲线及其曲线下面积(AUC),获得鉴别的最佳临界值。结果心电图S_D预测HBP合并LVH的敏感度、特异度及AUC分别为86. 05%、81. 65%、0. 892;心电图S_D+Sv4显示最高的敏感度为88. 37%。等效性检验显示单导联S_D的AUC较Cornell、Sokolow-Lyon及S_D+Sv4标准Z值均具有统计学差异(P0. 05)。心电图S_D诊断男性HBP合并LVH的AUC及敏感度、特异度分别为0. 901、90. 29%、75. 34%,等效性检验均优于Cornell、Sokolow-Lyon及S_D+Sv4标准(P 0. 05)。结论心电图S_D诊断HBP合并LVH,提高了其诊断的敏感性,优于Cornell和Sokolow-Lyon标准,值得临床推广。     

心电图对肥厚型心肌病左室肥厚诊断价值的评价

对１１１例肥厚型心肌病左室肥厚患者用心电图电压标准和Ｒｏｍｈｉｌｔ－Ｅｓｔｅｓ计分系统进行评价。结果：心民图电压标准和Ｒｏｍｈｉｌｔ－Ｅｓｔｅｓ计分系统诊断肥厚型心肌病左室肥厚的敏感性相似，分别为４１．４￥和３９．６％（Ｐ〉０．０５）。结论：心电图诊断肥厚型心肌病左室肥厚只有中等程度的敏感性，与电压标准比较，Ｒｏｍｈｉｌｔ－Ｅｓｔｅｓ计分系统并不提高诊断的敏感性。     

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.     

心电图诊断左室肥厚的可靠性

目的根据2003年欧洲高血压治疗指南,以超声左室重量指数LVMI作为诊断左室肥厚的参考标准,探讨心电图Sokolow-lyon指数和Cornell指数诊断高血压左室肥厚的敏感性和特异性.方法 280例高血压病患者,全部均经心超、心电图检查.按照心超左室重量指数,男性LVMI＞125 g/m2,女性LVMI＞110 g/m2作为左室肥厚诊断标准,根据心超阳性进行分组.分别计算心电图Sokolow-lyon指数和Cornell指数诊断左室肥厚的敏感性和特异性,采用x2检验判断二种方法的敏感性有无差异.结果 Cornell指数敏感性32%,特异性94%,Sokolow-lyon指数敏感性22%,特异性96%.经x2检验,二者间敏感性具有统计学差异.二者联合应用,则左室肥厚的检出率达35%.结论 Sokolow-lyon指数简便易行,但敏感性差;Cornell指数敏感性提高,但方法繁琐,需要计算机检测或放大测量,临床应用上需积累更多经验.     

壮族原发性高血压左心室肥厚患者不同心电图诊断指标的应用价值

目的探讨不同心电图诊断指标在壮族原发性高血压患者左心室肥厚临床诊断中的应用价值。方法选择壮族原发性高血压患者100例,以超声心动图检查所得到的左心室质量指数作为左心室肥厚诊断的参考标准,验证Cornell指数、Sokolow-Lyon指数和Romhilt-Estes积分3种心电图诊断指标的临床应用价值。结果以超声心动图诊断的左心室肥厚结果为标准,3种心电图指标均存在敏感性低,特异性高的特点;男性的诊断价值均大于女性;Romhilt-Estes积分高于Cornell指数和Sokolow-Lyon指数(P0.05)。结论 3种心电图指标可以作为诊断左心室肥厚的常规方法。     

心电图诊断左室肥厚的可靠性

目的　根据 2 0 0 3年欧洲高血压治疗指南 ,以超声左室重量指数LVMI作为诊断左室肥厚的参考标准 ,探讨心电图Sokolow lyon指数和Cornell指数诊断高血压左室肥厚的敏感性和特异性。方法　 2 80例高血压病患者 ,全部均经心超、心电图检查。按照心超左室重量指数 ,男性LVMI >12 5 g/m2 ,女性LVMI >110 g/m2 作为左室肥厚诊断标准 ,根据心超阳性进行分组。分别计算心电图Sokolow lyon指数和Cornell指数诊断左室肥厚的敏感性和特异性 ,采用 χ2 检验判断二种方法的敏感性有无差异。结果　Cornell指数敏感性 3 2 % ,特异性 94% ,Sokolow lyon指数敏感性 2 2 % ,特异性 96%。经 χ2检验 ,二者间敏感性具有统计学差异。二者联合应用 ,则左室肥厚的检出率达 3 5 %。结论　Sokolow lyon指数简便易行 ,但敏感性差 ;Cornell指数敏感性提高 ,但方法繁琐 ,需要计算机检测或放大测量 ,临床应用上需积累更多经验     

Improved sex-specific criteria of left ventricular hypertrophy for clinical and computer interpretation of electrocardiograms: validation with autopsy findings

In a previous study of 543 patients we developed, using echocardiographic left ventricular mass as the reference standard, two new sets of criteria that improve the electrocardiographic diagnosis of left ventricular hypertrophy (LVH). One set of criteria, which is suitable for routine clinical use, detects LVH when the sum of voltage in RaVL + SV3 (Cornell voltage) exceeds 2.8 mV in men and 2.0 mV in women. The second set of criteria, suitable for use in interpretation of the computerized electrocardiogram, uses logistic regression models based on electrocardiographic and demographic variables with independent predictive value for LVH, with separate equations for patients in sinus rhythm and atrial fibrillation. To test these criteria prospectively with use of a different reference standard, antemortem electrocardiograms were compared with left ventricular muscle mass measured at autopsy in 135 patients. Sensitivity of standard Sokolow-Lyon voltage (SLV) criteria (SV1 + RV5 or RV6 greater than 3.5 mV) for LVH was only 22%, but specificity was 100%. The Cornell voltage criteria improved sensitivity to 42%, while maintaining high specificity at 96%. Higher sensitivity (62%) was achieved by use of the new regression criteria, with a specificity of 92%. Overall test accuracy was 60% for SLV criteria, 68% for the Cornell voltage criteria, and 77% for the new regression criteria (p less than .005 vs SLV). We conclude that the Cornell voltage criteria improve the sensitivity of the electrocardiogram for detection of LVH and are easily applicable in clinical practice.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

Day-to-day variability of voltage measurements used in electrocardiographic criteria for left ventricular hypertrophy

Although electrocardiographic (ECG) voltage can be used to estimate left ventricular mass, day-to-day variability of voltage combinations used for this purpose must be established before ECG changes are taken as evidence of progression or regression of hypertrophy. Accordingly, serial ECGs (mean 8 days apart), derived from 10 s samples digitized at 250 Hz, were examined in 78 patients with no intercurrent change in clinical status. The coefficient of variation was calculated as 1 SD of the difference between paired voltage measurements, divided by the average mean value. Coefficient of variation for single leads was 22.3% for SV1, 27.0% for RV5 or RV6, 27.1% for RaVL and 34.7% for SV3. Coefficient of variation was lower for voltage combinations than for individual lead measurements: 18.5% for Sokolow-Lyon voltage (SV1 + RV5 or RV6), 22.3% for Gubner-Ungerleider voltage (R1 + S3) and 24.8% for Cornell voltage (RaVL + SV3). Serial reclassification due to variation above and below standard criteria for left ventricular hypertrophy occurred in only 3% of patients for Sokolow-Lyon voltage and 4% of patients for Cornell voltage in this group. Minute to minute reproducibility of voltage was assessed with electrodes in place in a separate group of 26 patients, and the coefficient of variation was 2.6% for Sokolow-Lyon voltage, 5.9% for Gubner-Ungerleider voltage and 2.9% for Cornell voltage. These data indicate that serial variability of computer-measured ECG voltage combinations is high, due primarily to changes in lead placement and body position, but less than the variability of computer-measured voltage in individual leads.     

Classification Accuracy of Electrocardiographic Criteria for Left Ventricular Hypertrophy in Normal Weight and Overweight Older Adults

Background: We evaluated classification accuracy of ECG criteria at varying levels of left ventricular hypertrophy (LVH) severity according to echocardiographically measured left ventricular mass (LVM) adjusted to body size. Methods: The test population was derived from the Cardiovascular Health Study (CHS), a population-based sample of 5201 men and women aged 65 and older, and consisted of 1844 women and 1119 men with adequate quality ECGs and echocardiograms for LVM determination. The criteria evaluated were Sokolow-Lyon, Cornell voltage, Cornell product, Framingham modification of the Cornell voltage, and the left ventricular mass index (LVMI) of the Novacode ECG program. Results: With LVH thresholds at upper 95% normal limit for weight adjusted LVM for the CHS population and ECG thresholds adjusted for 95% specificity in normal weight and overweight subgroups, the sensitivity of ECG criteria for LVH was relatively low. It was highest (40.8%) for the Novacode LVMI in normal weight men and for the Framingham criteria (30.9%) in normal weight women, but it deteriorated for both of these criteria in the presence of obesity. The overall performance of the Cornell product and Cornell voltage criteria was least influenced by obesity. The Framingham adjustment for the Cornell voltage criteria for obesity substantially reduced their sensitivity. Conclusion: The choice of echocardiographic standard, LVH severity level and overweight in the test groups have a strong influence on ECG evaluation results.     

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)     

Electrocardiographic diagnosis of exercise-induced left ventricular hypertrophy

To assess the prevalence of physiologic left ventricular hypertrophy and the usefulness of ECG criteria for its diagnosis, we compared ECGs and M-mode echocardiograms from 44 ultraendurance athletes and 20 similarly aged sedentary control subjects. Left ventricular mass was elevated in 25 of 44 (57%) athletes including 17 of 29 (59%) men greater than 134 gm/m2 and 8 of 15 (53%) women greater than 110 gm/m2. The sensitivity and specificity of the three ECG criteria used to diagnose left ventricular hypertrophy were: Sokolow-Lyon voltage (S-V1 + R-V5 greater than or equal to 3.5 mV), 65% and 61%; Romhilt-Estes score (greater than or equal to 4), 16% and 84%; and Cornell voltage (R-aVL + S-V3 greater than 2.8 mV in men and greater than 2.0 mV in women), 8% and 95%, respectively. Left ventricular mass, mass index, posterior wall thickness, chamber diameter, and relative wall thickness were not related to any measurement of QRS voltage. Nonvoltage ECG criteria for left ventricular hypertrophy were rare in athletes. Thus hypertrophy is a common but not universal adaptation to exercise. It is only moderately well detected by standard voltage criteria for left ventricular hypertrophy and is not reflected in nonvoltage criteria.     

New gender-specific partition values for ECG criteria of left ventricular hypertrophy: recalibration against cardiac MRI

ECG criteria for left ventricular hypertrophy (LVH) were mostly validated using left ventricular mass (LVM) as measured by M-mode echocardiography. LVM as measured by cardiac MRI has been demonstrated to be much more accurate and reproducible. We reevaluated the sensitivity and specificity of 4 ECG criteria of LVH against LVM as measured by cardiac MRI. Patients with systemic hypertension (n=288) and 60 normal volunteers had their LVM measured using a 1.5-Tesla MRI system. A 12-lead ECG was recorded, and 4 ECG criteria were evaluated: Sokolow-Lyon voltage, Cornell voltage, Cornell product, and Sokolow-Lyon product. Based on a cardiac MRI normal range, 39.9% of the hypertensive males and 36.7% of the hypertensive females had elevated LVM index. At a specificity of 95%, the Sokolow-Lyon product criterion had the highest sensitivity in females (26.2%), the Cornell criterion had the highest sensitivity in males (26.2%), and the Cornell product criteria had a relatively high sensitivity in both males and females (25.0% and 23.8%). Receiver operating characteristic curves showed the Cornell and Cornell product criteria to be superior for males whereas the Sokolow-Lyon product criterion was superior for females. Comparing the mean LVM index values of the subjects who were ECG LVH positive to the normal volunteers indicated that the ECG LVH criteria detect individuals with an LVM index substantially above the normal range. We have redefined the partition values for 4 different ECG LVH criteria, according to gender, and found that they detect subjects with markedly elevated LVM index.     

Gender differences in regression of electrocardiographic left ventricular hypertrophy during antihypertensive therapy

Although men and women differ in the magnitude of ECG left ventricular hypertrophy, whether gender differences exist in the degree of regression of ECG left ventricular hypertrophy during antihypertensive therapy is unclear. ECG left ventricular hypertrophy defined using gender-adjusted Cornell product and Sokolow-Lyon voltage criteria was assessed serially in 9193 hypertensive patients treated with losartan- or atenolol-based regimens. Changes in ECG left ventricular hypertrophy were measured from baseline to last in-study visit, and above-average regression of hypertrophy was identified by a >or=236-mm . ms reduction in Cornell product or >or=3.5-mm reduction in Sokolow-Lyon voltage. During mean follow-up of 4.8+/-0.9 years, women had less reduction in Cornell product (-149+/-823 versus -251+/-890 mm . ms) and Sokolow-Lyon voltage (-3.0+/-6.8 versus -4.8+/-7.7 mm) than men (both P<0.001). After adjusting for baseline ECG left ventricular hypertrophy levels, baseline and change in systolic and diastolic pressures, treatment group, age, and other baseline gender differences, women had significantly less reduction in both Cornell product (adjusted means: -137 versus -276 mm . ms; P<0.001) and Sokolow-Lyon voltage (-3.6 versus -4.1 mm; P=0.005) than men and were 32% less likely to have had greater than the median level of regression of Cornell product left ventricular hypertrophy (95% CI: 24% to 39%; P<0.001) and 15% less likely to have had regression of left ventricular hypertrophy by Sokolow-Lyon criteria (95% CI: 5% to 23%; P=0.003). Thus, women have less regression of ECG left ventricular hypertrophy than men in response to antihypertensive therapy, independent of baseline gender differences in the severity of ECG left ventricular hypertrophy and after taking into account treatment effects and blood pressure changes.     

Left ventricular hypertrophy in relation to systolic blood pressure and the angiotensin converting enzyme I/D polymorphism in Chinese

Objective There is little population-based data on the prevalence and the environmental or genetic determinants of left ventricular hypertrophy （LVH） in China. The purpose of this paper is to study LVH in relation to systolic blood pressure and the angiotensin converting enzyme （ACE） insertion/deletion（I/D） polymorphism in Chinese. Methods We recorded 12- lead ECG （CardioSoft, v4.2） in 1365 residents in the Jingning County, Zhejiang Province, China. LVH was defined according to the gender-specific Sokolow-Lyon and Cornell product ECG criteria. Results Regardless of whether the Sokolow-Lyon or Cornell product ECG criteria was used, the prevalence of LVH （20.7% and 4.8%, respectively） significantly （P〈0.0001） increased with male gender （odds ratio [OR] 2.33 and 7.15） and systolic blood pressure （per 10 mm Hg increase, OR 1.46 and 1.33）. If the Sokolow-Lyon criteria was used, the prevalence of LVH was also influenced by alcohol intake （OR 1.44, P=-0.03） and body mass index （OR 0.83, P=0.0005）. The association between the Sokolow-Lyon voltage amplitude and the ACE I/D polymorphism was dependent on antihypertensive therapy （P=0.01）. In 1262 untreated subjects, but not 103 patients on antihypertensive medication, the ACE DD compared with II subjects had significantly higher Sokolow-Lyon voltage amplitudes （29.8：-0.6 vs. 28.0-3：0.5 mV, P=-0.02） and higher risk of LVH （OR 1.74, 95% CI： 1.12-2.69, P=-0.01）. Conclusion LVH is prevalent in Chinese, and is associated with systolic blood pressure and the ACE D allele. The genetic association might be modulated by antihypertensive therapy（J Geriatr Cardio12009; 6：131-136）.