摘要目的:研究高血压左室肥厚病人不同心电图改变的预后价值。方法:对126例高血压合并左室肥厚的20多项心电图改变进行预后追踪14年，以性别、年龄、职业、地区配对的正常高血压275人，无左室肥厚高血压患者163人做为非暴露组进行队列研究，观察各种心脑血管并发症的发生率，评价各项心电图改变的相对危险度(RR)。结果:高血压和高血压合并左室肥厚病人死亡的主要原因是心脑血管意外(56.8%)。单纯左室高电压不是高血压患者独立的危险因子。不对称倒置T波、左室劳损、V₁ Ptf异常、Q_V5≥2 mm及多项心电图指标异常者发生心脑血管并发症的危险性明显升高，分别为正常人的30.67，14.75，14.73，12.48，和11.24倍。矫正血压和电压因素后这些心电图异常的危险性仍高，其RR分别为6.55，2.99，3.19，2.32，和2.26。结论:不对称倒置T波、左室劳损、V₁ Ptf异常、Q_V5≥2 mm及多项心电图指标异常是既独立于血压因素又独立于电压因素之外的发生心脑血管并发症的危险因子

要点：高血压合并左室肌厚有不对称倒置T波、左室劳损、V₁ Ptf、Q_V5≥2 mm者，经14年观察其发生心脑血管并发症的危险性分别为正常人的11倍到30倍

中图分类号：R544.1;R541.3;R444文献标识码：A

文章编号：1006-2866(1999)03-0213-06

The Prognostic Significance of Various Electrocardiographic Changes in Hypertensive Patients with Left Ventricular Hypertrophy

XIE Liangdi,CHEN Daguang,WU Kegui,CHEN Jinshui

(Hypertension Division,The First Affiliated Hospital of Fujian Medical College,Fuzhou 350005 P.R.CHINA)

Objective:To investigate the prognostic significance of ECG changes in hypertensive patients with left ventricular hypertrophy.Methods:One hundred twenty six hypertensives with left ventricular hypertrophy (HT-LVH) were followed up for 14 years.A cohort of age,sex,region and occupation matched hypertensives without LVH (HT,n=163) and normotensives (NT,n= 275) served as controls.Correlation between 20 specific items of electrocardiographic abnormalities and cerebral-cardiovascular events were studied,and the relative risks (RR) were evaluated.Results:It was showed that the major causes of death in hypertensives with ECG LVH in this study was stroke (56.8%).LVH based on voltage criteria only was not risk factor,the higher incidence of cardiovascular events was ascribed to coexisting higher level of BP usually accompanying higher ECG voltage.Electrocardiographic manifestations of asymmetric inverted T wave,ST segment depression,V₁ Ptf≤0.04 mm.sec,Q_V5≥2mm and comprehensive abnormalities in patients with hypertension increased the risk of cardiovascular events,with the RR of 30.67,14.75,14.73,12.48 and 11.24 respectively,as compared to the normotensives.After stratification of voltage and adjustment of coexisting hypertension,the risks of above abnormalities were still significant,with RR of 6.55,2.99,3.19,2.32 and 2.26 respectively.Conclusion:Asymmetric inverted T wave,ST segment depression,V₁ Ptf≤0.04 mm.sec,Q_V5≥2 mm and comprehensive abnormalities are independent risk factors for hypertensives.

Key Words:Hypertension;Left ventricular hypertrophy;Electrocardiography;Prognosis

It has long been recognised that left ventricular hypertrophy (LVH) is an independent risk factor for cardiovascular diseases^［1-7］.Currently,two dimensional echocardiography has been widely used in clinical practice,however,the standard 12-lead electrocardiogram (ECG) remains a practical,economic,uncomplicated and convenient method to detect LVH.Though the sensitivity of detection of left ventricular hypertrophy with echocardiography is much higher than that with ECG,while the specificity of ECG is much better^{［4,6,10～12］}.Therefore ,the 12-lead ECG remains the most widely used initial diagnostic test in the survey for left ventricular hypertrophy.In the most previous studies,the prognosis of left ventricular hypertrophy were carried out based on the different multiple criteria^{［1,4,12-16］}.However,studies on the prognosis of specific ECG changes regarding LVH were scanty.The present study was carried out in the southern part of Fujian province P.R.China,where 126 hypertensive patients with ECG-LVH diagnosed during a servey for hypertension.The patients were matched with a cohort of normotensives in age,sex,region,and occupation.The patients were followed up for 14 years,to investigate the prognostic importance of various specific ECG changes in hypertensives with LVH.

SUBJECT AND METHODS

Study protocol

This study was initiated in 1974 in the southern part of Fujian province,including Yongchun,Anxi,Quanzhou and Chendi 4 mountain communities^［17-19］.A total of 26,642 people over 15 years old were survey for hypertension.Each subject underwent the same protocol described previously^{［17～19］}.Briefly,the determination of sitting blood pressure after 30 min rest with a mercury sphygmomanometer (Korotkoff phase I and V) was used as the mean of the two readings on three consecutive days.Measurement of body weight and height,physical examination,quantification of fasting plasma cholesterol ,triglyceride and serum glucose,routine tests of blood and urine samples,examination of ocular fundus were routinely performed.

Electrocardiographic method

Standard 12-lead electrocardiograms were recorded in all subjects at 25 mm/s and 1 mV/cm calibration.Tracings were interpreted by 2 experienced investigators.Subjects with complete bundle branch block,previous myocardial infarction,Wolff-Parkinson-White syndrome,and atrial fibrillation were excluded from the analysis.No subject was being treated with digitalis.One hundred twenty six hypertensives with electrocardiographic left ventricular hypertrophy (HT-LVH) based on R_V5+S_V1≥40 mm ( for male,35 mm for female) were followed up for 14 years to investigate the prognostic value of various specific ECG changes in hypertensive patients with LVH.These ECG changes included :(1) R wave in lead Ⅰ (R_Ⅰ)≥15 mm;(2) Sum of R wave in lead I+S wave in lead Ⅲ (R_I+S_Ⅲ) ≥25 mm;(3) ST segment depression in lead Ⅰ (ST_Ⅰ)≥ 1 mm and /or presence of inverted T wave in lead I;(4) R wave in lead aVL (R_aVL)≥12 mm;(5) R wave in lead aVF (R_aVF ) ≥20 mm;6)The sum of R wave in lead Ⅰ+ R wave in lead Ⅱ ( R_Ⅰ+ R_Ⅱ)≥40 mm ;(7) Deviation of QRS axis≤-30°;(8) P wave terminal force in lead V₁ (V₁ Ptf) ≤-0.04mm·s;(9) R_V5 + S_V1 ≥40 mm;(10) S_V1 ≥22 mm;(11) S_V3≥25 mm;(12) R_V5 or _V6≥25 mm;(13) Q wave in V5 (Q_V5) ≥2 mm;(14) ST_V5 or _V6 depression ≥1 mm,or inverted T wave in V₅ or V₆ ;(15)QRS duration in lead V₅ or V₆ (T_QRS) ≥0.09 s;(16)Presence of U wave;(17) Inverted U wave;(18) Asymmetrically inverted T wave;(19)T wave overshot in pericardial leads;(20) Ventricular activation time in V₅ or V₆ (VAT_V5 or_V6)≥0.05 s.

The abnormalities were classified into 3 categories :(1) voltage abnormality only:If any of about voltage abnormalities was present;(2) Left ventricular hypertrophy with strain:Abnormal ST segment depression or T wave inversion beside high voltage;(3) Multiple abnormalities:one or more non-voltage abnormalities in addition to voltage criteria.

Follow-up and end point evaluation