|Year : 2016 | Volume
| Issue : 2 | Page : 75-79
Electrocardiogram and echocardiographic study of left ventricular hypertrophy in patients with essential hypertension in a teaching medical college
K Venugopal, Srikant R Gadwalkar, P Ramamurthy
Department of General Medicine, Vijayanagara Institute of Medical Sciences, Bellary, Karnataka, India
|Date of Web Publication||18-May-2016|
Department of General Medicine, Vijayanagara Institute of Medical Sciences, Room No. 17, 17th Block, Bellary - 583 104, Karnataka
Source of Support: None, Conflict of Interest: None
Background: Left ventricular hypertrophy (LVH) is the adaptive mechanism for increased left ventricular (LV) stress and is associated with many adverse events. This study was undertaken to study LVH in patients of essential hypertension and to correlate between clinical, electrocardiogram (ECG), and echocardiography (ECHO) in the identification of LVH. Materials and Methods: One hundred patients attending the outpatient department and those who were admitted in our teaching institute from January 2013 to June 2014 were the study subjects. All cases of essential hypertension, irrespective of the duration of hypertension and type of treatment received were included in the study. Patients with secondary hypertension, ischemic heart disease/myocardial infarction, ischemic cardiomyopathy, congenital heart disease, and valvular heart disease were excluded. Conclusion: Out of the different ECG criteria, total QRS criteria showed a high sensitivity of 60%. ECG criteria have a high specificity but low sensitivity and hence, have limited use as a screening method. However, in a resource-poor country such as India where ECHO facilities are not available in all rural regions, improved ECG criteria such as total QRS voltage can be recommended as a routine investigation for LVH because of its cost-effectiveness and easy availability despite certain limitations.
Keywords: Echocardiography (ECHO), left ventricular hypertrophy (LVH), Romhilt-Estes, Sokolow-Lyon
|How to cite this article:|
Venugopal K, Gadwalkar SR, Ramamurthy P. Electrocardiogram and echocardiographic study of left ventricular hypertrophy in patients with essential hypertension in a teaching medical college. J Sci Soc 2016;43:75-9
|How to cite this URL:|
Venugopal K, Gadwalkar SR, Ramamurthy P. Electrocardiogram and echocardiographic study of left ventricular hypertrophy in patients with essential hypertension in a teaching medical college. J Sci Soc [serial online] 2016 [cited 2020 Aug 9];43:75-9. Available from: http://www.jscisociety.com/text.asp?2016/43/2/75/182600
| Introduction|| |
Hypertension is one of the common public health problems and most of the patients remain asymptomatic. Left ventricular hypertrophy (LVH) is an adaptive state of the heart for increased wall stress. It is common in hypertension. The prevalence of LVH increases with age, the severity of hypertension, and duration of hypertension. So, the presence of LVH indicates a long run of uncontrolled hypertension.
LVH is a common condition that profoundly affects morbidity and mortality from cardiovascular diseases including myocardial infarction, congestive heart failure, and stroke. The prevalence of LVH is on the rise and it is more alarming in the developing nations. The Framingham heart study suggested that one in 10 persons will have LVH in age range of 65-69 years.  LVH is no longer considered an adaptive process that compensates the pressure imposed on the heart and has been identified as an independent and significant risk factor for sudden death, acute myocardial infarction, and congestive heart failure.  The study also stated that electrocardiogram (ECG)-diagnosed LVH was associated with a three- to fivefold increase of cardiovascular events with greater risk ratios for cardiac failure and stroke.
The studies clarify a strong relation between LVH and adverse outcome and hence, emphasize the clinical importance for its detection.  The increase in left ventricular (LV) mass represents a final pathway toward the adverse effects on the cardiovascular system and higher vulnerability to complication.  ECG in the assessment of cardiac dimensions has lost its prominence in favor of imaging techniques that provide a multidimensional display of the heart but secondary ST-T changes due to LVH that are uniquely determined from ECG are known to increase the risk of cardiovascular morbidity and mortality. 
There are many ways of diagnosing LVH such as by ECG, roentgenography, and echocardiography (ECHO). Though ECHO is superior to ECG, it is expensive and not widely available in the rural regions of India. So, the purpose of this study is to explore the reliability of ECG in the diagnosis of LVH as compared to ECHO.
| Materials and methods|| |
In this study, 100 patients of essential hypertension who visited the outpatient department of our hospital for follow-up and the patients admitted in medicine wards were included in the study according to the inclusion and exclusion criteria. All the patients were evaluated with detailed clinical history and physical examination. All the patients were subjected to ECG and ECHO with color Doppler. Clinical detection of LVH was done by the position of apical impulse. The patients whose apical impulse was below the 6th intercostal space and 1-2 cm lateral to the left midclavicular line were considered as having LVH. ECG criteria used in this study were Sokolow-Lyon, Romhilt-Estes, and total QRS voltage criteria [Table 1]. Comprehensive two-dimensional (2D) tomographic planes were employed with multiple parasternal views of the left ventricle in the long and short axes after positioning of the cursor through the interventricular septum and posterior wall at the level of chordae tendineae; simultaneous M-mode and 2D recordings were obtained from the parasternal transducer position in both the long and short axes of the ventricle. M-mode measurements were taken by the leading edge-to-leading edge technique, as recommended by the American Society of Echocardiography. All measurements were averaged to the closest 1 mm from three good quality cardiac cycles. LV mass was obtained from the LV short axis diameter and a simple geometric cube formula with the following equation:
Left ventricular mass (LVM) = 1.04 [(LVID + PWT + IVST) 3-LVID3] × 0.8 + 0.6.
Here, 1.04 is the specific gravity of myocardium and 0.8 is the correction factor. All the measurements were taken at end diastole in diameter.  In females, LV mass of 163-186 g/m 2 was taken as mild LVH, 187-210 g/m 2 was taken as moderate LVH, and >211 g/m 2 was taken as severe LVH. In males, LV mass of 225-258g/m 2 was taken as mild LVH, 259-292g/m 2 was taken as moderate LVH, and >293g/m 2 was taken as severe LVH.
Data obtained from these patients were systematically recorded and analyzed using the statistical package for social services (SPSS) version 15.0 (SPSS version 15.0, IBM SPSS inc., Chicago, IL) and chi-square test was used to assess statistical significance. A P value of <0.05 was considered to be statistically significant. The statistical tests were performed after obtaining the results of ECG and ECHO diagnostic validity tests (sensitivity and specificity), Kappa measurement of agreement.
| Results|| |
Out of 100 patients, 59 (59%) were males and 41 (41%) were females. Among 59 males, 36 (61.01%) showed LVH and among 41 females, 24 (58.53%) showed LVH. The majority of cases was in the age group of 50-59 years (n = 48, 48%). The youngest patient was aged 40 years and the oldest patient was aged 87 years and the mean age was 56.4 years.
Out of 40 smokers, 33 had LVH as determined from ECHO and out of 60 nonsmokers, 27 had LVH as determined from ECHO. This was statistically significant (P < 0.0001). Family history of hypertension was present in 47 (47%) patients. Among 47 patients, 23 (48.93%) showed LVH in ECHO. Fifty-three (53%) patients had no family history of hypertension. Among 53 patients, 37 (69.81%) showed LVH in ECHO. This comparison was statistically significant (P < 0.0001).
In this study, 8 out of 10 who had hypertension for the past 16-20 years had LVH and 6 out of 6 patients who had hypertension for more than 21 years had LVH. This study shows that as the duration of hypertension increases, the chances of LVH increase too. This was highly significant statistically (P < 0.0001).
Out of 100 patients, clinical evidence of LVH was noted in 18 (18%) patients. Among the 18 patients, 12 (66.66%) were males and 6 (44.44%) were females. Sokolow-Lyon criteria identified LVH in 24 patients. Among them, 18 (75%) were males and 6 (25%) were females. Romhilt-Estes criteria identified LVH in 28 patients. Among them, 16 (57.14%) were males and 12 (42.85%) were females. Total QRS voltage criteria identified LVH in 36 patients. Among them, 20 (55.55%) were males and 16 (44.44%) were females. ECHO identified LVH in 60 patients. Among them, 36 (60%) were males and 24 (40%) were females [Figure 1]. Out of 60 patients, 29 had mild LVH, 16 had moderate LVH, and 15 had severe LVH [Figure 2].
|Figure 1: Identification of the left ventricular hypertrophy by various methods in the study group|
Click here to view
|Figure 2: Distribution of the study group according to the severity of left ventricular hypertrophy by echocardiography|
Click here to view
Out of 24 patients with blood pressure (BP) <140 mmHg, 6 (25%) had LVH. Eighteen (58.08%) out of 31 patients had LVH with BP of 140-159 mmHg. Twenty-eight (77.78%) out of 36 patients had LVH in the BP group of 159-180 mmhg. Eight (88.89%) out of nine patients had LVH with BP > 180 mmHg. Out of 24 patients with BP <90 mmHg, 4 (16.6%) had LVH. Seventeen (53.12%) out of 32 patients had LVH in the BP group of 140-159 mmHg. Thirty (85.71%) out of 35 patients had LVH in the BP group of 100-109 mmHg. Eight (88.89%) out of nine patients had LVH with BP > 110 mmHg. Sixty patients presented with various complaints, out of whom 40 had LVH. Out of 40 follow-up patients, 20 had LVH [Figure 3].
Out of 100 patients, diastolic dysfunction was noted in 54 (54%) patients. Thirty-four patients had grade 1 diastolic dysfunction, 15 patients had grade 2 diastolic dysfunction, and 5 patients were noted to have grade 3 diastolic dysfunction [Figure 4].
|Figure 4: Distribution of the study group according to left ventricular diastolic dysfunction|
Click here to view
Clinical evaluation showed LVH in 18 patients. Sensitivity was 30%, specificity was 100%, positive predictive value (PPV) was 100%, negative predictive value (NPV) was 48.78%, accuracy was 58%, and Kappa measure of agreement was 0.25. Chi-square test was used to compare ECHO and clinical detection found significant.
ECG of Sokolow-Lyon index could diagnose LVH in a total of 28 patients. Out of these 28 patients, only 24 had LVH by 2D ECHO. Sensitivity was 40%, specificity was 90%, PPV was 85.7%, NPV was 50%, accuracy was 60%, and Kappa measure of agreement was 0.27. Chi-square test was used to compare ECHO and ECG of Sokolow-Lyon criteria found significant.
ECG of Romhilt-Estes criteria could diagnose LVH in a total of 36 patients. Out of these 36 patients, only 28 patients had LVH as determined by 2D ECHO. Sensitivity was 41.17%, specificity was 80%, PPV was 77.78%, NPV was 53.3%, accuracy was 60%, and Kappa measure of agreement was 0.24. Chi-square test was used to compare ECHO and ECG of Romhilt-Estes criteria found not significant.
ECG of total QRS voltage criteria could diagnose LVH in a total of 39 patients. Out of these 39 patients, 36 had LVH as determined by 2D ECHO. Sensitivity was 60%, specificity was 92.5%, PPV was 92.3%, NPV was 60.6%, accuracy was 73%, and Kappa measure of agreement was 0.49. Chi-square test was used to compare ECHO and ECG of total QRS voltage criteria found significant.
| Discussion|| |
Our study compared the three most important ECG criteria for the diagnosis of LVH in hypertensive patients with ECHO as the diagnostic tool. Sokolow-Lyon criteria are the oldest criteria devised by Sokolow M. and Lyon in 1949. It is the oldest, simplest, and quickest method for the detection of LVH by ECG. In our study, it had sensitivity of 40%, specificity of 90%, PPV of 85.7%, NPV of 50%, accuracy of 60%, and Kappa measure of agreement of 0.27. The sensitivity and specificity of Sokolow-Lyon criteria has been studied in various studies [Table 2].
A Romhilt-Estes point score system was proposed in 1968 and it involves complicated data acquisition for scoring. Total score is 13 and when 4 points (probable LVH) are used as criteria, it increases the sensitivity and specificity but when 5 points (definite LVH) are used as criteria, it decreases the sensitivity and specificity. In the present study, 5 points were used and it showed following results. In our study, it had sensitivity of 41.17%, specificity of 80%, PPV of 77.78%, NPV of 53.3%, accuracy of 60%, and Kappa measure of agreement of 0.24. The sensitivity and specificity of Romhilt-Estes point score has been studied in various studies [Table 3].
|Table 3: Romhilt-Estes point score system in previous studies and the present study|
Click here to view
Total QRS voltage criteria were devised by Roberts et al. A total QRS voltage greater than 175 mm was taken as diagnostic. In our study, it had sensitivity of 60%, specificity of 92.5%, PPV of 92.3%, NPV of 60.6%, accuracy of 73%, and Kappa measure of agreement was 0.49. The sensitivity and specificity of Romhilt-Estes point score has been studied in various studies [Table 4].
|Table 4: Total QRS voltage criteria in previous studies and the present study|
Click here to view
| Summary and conclusion|| |
We studied 100 hypertensive patients for the comparison of clinical and different criteria of ECG in the diagnosis of LVH with ECHO as the diagnostic standard.
Financial support and sponsorship
- In our study, the clinical detection of LVH showed a sensitivity of 30% and a specificity of 100%.
- Sokolow-Lyon criteria showed a sensitivity of 40% and a specificity of 90%.
- Romhilt-Estes scoring system showed a sensitivity of 41.2% and a specificity of 80%.
- Total QRS criteria showed a sensitivity of 60% and a specificity of 90.5%.
- Among the different criteria used, total QRS criteria showed better sensitivity compared to others in the present study.
- ECG criteria have a high specificity but low sensitivity. Hence, its use as a screening method is limited.
- In the evaluation of hypertensive patients for LVH, ECHO is the method of choice.
- However, in a resource-poor country such as India where ECHO facility is not available in all the rural regions, improved ECG criteria such as total QRS voltage can be recommended as a routine investigation for LVH because of its cost-effectiveness and easy availability with certain limitations.
Conflicts of interest
There are no conflicts of interest.
| References|| |
Friedman MJ, Roeske WR, Sahn DJ, Larson D, Goldberg SJ. Accuracy of M mode echocardiographic measurements of the left ventricle. Am J Cardiol 1982;49:716-23.
Devereux RB. Does increased blood pressure cause left ventricular hypertrophy or vice versa? Ann Intern Med 2000;112:157-9.
Vakili BA, Okin PM, Devereux RB. Prognostic implications of left ventricular hypertrophy. Am Heart J 2001;141:334-41.
Devereux RB, Reichek N. Echocardiographic determination of left ventricular mass in men. Anatomic validation of the method. Circulation 1997;55:613-8.
Martinova E. Automated computer analysis in diagnosis of left ventricular hypertrophy by electrocardiography. Journal of Electrocardiology 2007;40:S41-2.
Connolly HM, Jal KO. Echocardiography. In: Bonow RO, Mann DL, Zipes DP, Libby P, editors. Braunwald's Heart Disease: A Text Book of Cardiovascular Medicine. 8 th
ed. Philadelphia: Saunders; 2008. p. 245-6.
Reichek N, Devereux RB. Left ventricular hypertrophy: Relationship of anatomic, echocardiographic and electrocardiographic findings. Circulation 1981;63:1391-8.
Murphy ML, Thenabadu PN, de Soyza N, Meade J, Doherty JE, Baker BJ. Sensitivity of electrocardiographic criteria for left ventricular hypertrophy according to type of cardiac disease. Am J Cardiol 1985;55: 545-9.
Devereux RB, Casale PN, Kligfield P, Eisenberg RR, Miller D, Campo E, et al
. Performance of primary and derived M-mode echocardiographic measurements for detection of left ventricular hypertrophy in necropsied subjects and in patients with systemic hypertension, mitral regurgitation and dilated cardiomyopathy. Am J Cardiol 1986;57: 1388-93.
Odom H 2 nd
, Davis JL, Dinh H, Baker BJ, Roberts WC, Murphy ML. QRS voltage measurements in autopsied men free of cardiopulmonary disease: A basis for evaluating total QRS voltage as an index of left ventricular hypertrophy. Am J Cardiol 1986;58:801-4.
Norman JE Jr, Levy D. Improved electrocardiographic detection of echocardiographic left ventricular hypertrophy: Results of a correlated data base approach. J Am Coll Cardiol 1995;26:1022-9.
Jaggy C, Perret F, Bovet P, van Melle G, Zerkiebel N, Madeleine G, et al
. Utility of electrocardiogram for predicating increased left ventricular mass in asymptomatic men at risk for cardiovascular disease. Am J Hypertens 1998;11:861-5.
Jaggy C, Perret F, Bovet P, van Melle G, Zerkiebel N, Madeleine G, et al
. Performance of classic electrocardiographic criteria for left ventricular hypertrophy in an African population. Hypertension 2000;36: 54-61.
Warram JH, Laffel LM, Valsania P, Christlieb AR, Krolewski AS. Excess mortality associated with diuretic therapy in diabetes mellitus. Arch Intern Med 1991;151:1350-6.
Kansal S, Roitman DI, Sheffield LT. A quantitative relationship of electrocardiographic criteria for left ventricular hypertrophy with echocardiographic left ventricular mass: A multivariate approach. Clin Cardiol 1983;6:456-63.
Hameed W, Razi MS, Khan MA, Hussain MM, Aziz S, Habib S, et al
. Electrocardiographic diagnosis of left ventricular hypertrophy: Comparison with echocardiography. Pak J Physiol 2005;1:35-8.
Waseem T, Nadeem MA, Ali T, Khan AH. Left ventricular hypertrophy (LVH): Sensitivity of different electrocardiographic criteria to diagnose LVH in patients having increased left ventricular mass index on echocardiography. Ann King Edward Med Uni 2003;9:101-4.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4]