Electrocardiographic Diagnosis of Left Ventricular Hypertrophy- The Effect of Left Ventricular Wall Thickness, Size, And Mass on the Specific Criteria for Left Ventricular Hypertrophy

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Electrocardiographic diagnosis of left ventricular

hypertrophy: The effect of left ventricular wall

thickness, size, and mass on the specific criteria

for left ventricular hypertrophy Navin Budhwani, MD, Sanjeev Patel, MD, and Edward M. Dwyer, Jr, MD Newark, NJ

Background The purpose of our study was to determine the relative importance and effect of an increased left

ventricle wall thickness, left ventricular diastolic diameter, and left ventricular mass (LVM) on the performance of the 4 majorelectrocardiogram (ECG) criteria of left ventricular hypertrophy (LVH) and to determine how these findings could be

incorporated into the routine ECG interpretation of LVH.

Methods The ECG criteria of LVH that we chose to examine were voltage, repolarization abnormalities, left atrial

abnormality, and ventricular conduction time. We analyzed data from 608 consecutive patients with left ventricular wall

thickness of N13 mm on the echocardiogram and with a concurrent ECG. We arbitrarily divided patients into 3 groups(groups I-III) according to the calculated LVM. Group I had an LVM of b400 g; group II had an LVM from 400 to 600 g, and

group III had an LVM of N600 g. We evaluated the effect of increasing LVM, wall thickness, and ventricular diameter on the

performance of the 4 ECG criteria at different severity of thickness, diameter, and mass.

Results An increase in the echocardiogram-derived LVM had significant effect on all 4 ECG criteria. As LVM

progressively increased from groups I to III, the frequency of voltage criteria for LVH increased from 52% to 83%; left atrial

abnormality rose from 46% to 68%; ST-T wave changes increases from 55% to 95%, and QRS prolongation significantly

increased from 42% to 70%.

Conclusion Increased wall thickness and ventricular diameter failed to correlate with the overall ECG score or

significantly influence the frequency of any of the 4 ECG criteria for LVH in patients when LVM was held relatively constant.

We also demonstrated that an increasing number of criteria on the ECG are associated with a greater mean LVM. (Am Heart J2005;149:709-14.)

The electrocardiographic diagnosis of hypertrophy of

the left ventricle (LVH) has been a source of activ e

investigation since the initial observations by Lewis1 in

1914. The original reference standards, used in the

development of specific electrocardiographic criteria for

the presence of LVH, were either by autopsy measure-

ments2 or clinical assessment.3 As a reference standard,

autopsy data allowed for accurate determination of

ventricular weight but had an inherent selection bias,

whereas a diagnosis of LVH made by clinical criteria was widely applicable but was frequently inaccurate and

could not provide a quantitative determination of LVH.

Echocardiography has provided an excellent technique

to measure left ventricular mass (LV M).4 Th is technique

provides an excellent reference standard by which we

can contemporaneously assess the validity of specific

electrocardiographic criteria used for the diagnosis of

LVH. Although the echocardiogram is extremely accurate

in its ability to diagnose LVM, the electrocardiogram

(ECG) is more widely used because of its easy perfor-

mance and low cost. The clinical diagnosis of LVH, in

disorders such as hypertension and valvular disease

carries important prognostic implications.5,6 For these

reasons, it is important to understand both the capabil-ities and limitations of the ECG in the diagnosis of LVH.

Many excellent studies have been published which

have attempted to refine or confirm the value of some of

the ECG criteria widely used in the diagnosis of LVH .7-9

The electrocardiographic diagnosis of LVH has been

shown to have reasonable specificity but lacks sensitiv-

ity. The degree of sensitivity described by many studies

lies between 40% and 60%.10

Although LVH, at the most basic level, is defined as an

enlargement of cardiac myocytes, the clinical repre-

sentations of LVH that are most common are increased

wall thickness or ventricular mass. An increased LVM

From the Department of Medicine, Division of Cardiovascular Diseases, New Jersey

Medical School/UMDNJ, Newark, NJ.

Submitted April 11, 2004; accepted July 6, 2004.

Reprint requests: Edward M. Dwyer, MD, Division of Cardiovascular Diseases, NJ

Medical School, MSB I-536, 185 S Orange Ave, Newark, NJ 07103.

0002-8703/$ - see front matter

n 2005, Elsevier Inc. All rights reserved.

doi:10.1016/j.ahj.2004.07.040



can be characterized by different geometric forms.

There is an increased wall thickness and normal left

ventricular size at one end of the spectrum, whereas at

the other end of the spectrum, there is increased left

ventricular size and normal wall thickness. The perfor-

mance of the several commonly used ECG criteria may vary as LVM increases. Each of the ECG criteria may

also, individually, perform differently in the presence of

concentric hypertrophy than they do in the presence of

eccentric hypertrophy. There is limited understanding

of the contribution and importance of left ventricular

thickness, ventricular size, or overall LVM on the value

and performance of the individual criteria such as ECG

voltage, repolarization abnormalities, and alterations in

atrial and ventricular conduction.

The purpose of our study is to determine the relative

importance and effect of an increased left ventricular

wall thickness, left ventricular diastolic diameter, and

LVM on the performance on each of the 4 major ECGcriteria for LVH and to determine how the findings can

be incorporated into the use of the routine ECG for the

interpretation of LVH.

MethodsStudy group

After exclusions, we analyzed data from 608 consecutive

patients for study (obtained N2 years) from the echocardio-

graphic and electrocardiographic databases at UMDNJ

University Hospital, who had a septal and posterior wall

thickness z14 mm on the echocardiogram. We retrievedcomplete echocardiographic data along with the ECG for each

patient. The ECG was obtained within a mean of 7 days of the

echocardiogram. We excluded patients with inadequate tech-

nical quality on the echocardiogram and ECG evidence of a

Q wave myocardial infarct, atrial fibrillation, complete left or

right bundle-branch block , and a paced rhythm. Standard ECG

criteria were adopted.11 T wo physicians, who had no knowl-

edge of the echocardiographic findings, separately performed

an analysis of the ECG. All disagreements were resolved

between the 2 readers.

Electrocardiographic measurementsOur technical staff recorded a standard 12-lead ECG, on

Marquette computerized recorders, at 25 mm/s and 1 mV/cmstandardization with equipment having frequency response

characteristics in accor dance with American Heart Association

recommendations.12

The tracings were interpreted for the presence or absence of

the following 4 criteria for LVH:

(1) Increased voltage,

(2) ST depression and/or T-wave inversion,

(3) Left atrial enlargement, and

(4) Prolonged QRS conduction time.

We calculated a point score according to the system

proposed by Romhilt and Estes.9 In this system, each of the

criteria is graded as 3 points except QRS duration which is

awarded 1 point. The total score ranges from 0 to 10.QRS amplitude was measured to the nearest microvolt on a

digitized ECG. The presence of increased voltage was calcu-

lated using the modified Cornell criteria. These more recent

criteria are (for men: S in V 3 plus R in aVL N2.8 mV [28 mm],

and for women: S in V 3 + R in aVL N2.0 mV [20 mm]).13 L eft

atrial abnormality was coded as present if the P-wave inversion

in lead V 1 was N1 mm in length and N1 mV in amplitude. ST

depression N0.1 mV and/or T-wave inversion of any degree

were considered present if found in any lead except aVR,

and V 1 to V 3. QRS duration was measured to the nearest

10 milliseconds and was considered abnormal when the

duration was z100 milliseconds.9

Echocardiographic measurementsComprehensive 2-dimensional and Doppler echocardiogra-

phy was performed on all patients. Left ventricular dimensions

(intraventricular septal thickness, posterior wall thickness, and

left ventricular end-diastolic diameter) were measured at end

of diastole with M-mode by using leading-edge–to–leading-

edge convention. Left ventricular mass (g) was calculated

using the Penn cube convention with the following formula:

LVM = 1.04[(LVEDD + PW + IVS)3 À (LVEDD)3] À 13.6,

where LVEDD is the left ventricular end diastolic diameter;

PW is the posterior wall thickness, and IVS is the intraven-

tricular septal thickness.

Data analysisGroup subsets. We arbitrarily divided patients into 3 groups

(groups I-III) according to the calculated LVM. We intended

these groups to reflect mild, moderate, and severe hypertro-

phy. The groups represent approximate 200-g increments in

LVM. All patients in group I had an LVM b400g; group II had an

LVM from 400 to 600 g, and group III had an LVM N600 g.

Left ventricular wall thickness. To evaluate the contribu-

tion of wall thickness to the performance of the 4 ECG criteria,

we compared the frequency of each of the ECG criteria

between 2 extreme groups (A and B) of wall thickness. In

group A, all patients had both septal and posterior wall

thickness between 14 and 15 mm. In group B, all patients had

at least one wall thickness z17 mm. To eliminate the influence

Table I. Echocardiographic measurements in 608 patients withincreasing LVM

Echocardiogrammeasurements

Group I Group II Group III

(bbbbbbbb400 g) (400-600 g) (NNNNNNNN600 g)

n = 290 n = 255 n = 63

Mean LV mass (g) 318 480 718Mean LV wall

thickness (mm)15 17 18.5

Mean LV diastolicdiameter (mm)

41 51 60

LV , Left ventricle.

American Heart Journal

April 2005710 Budhwani, Patel, and Dwyer



of LVM, we restricted both groups to patients with an LVM

b400 g so that both groups had a similarly low LVM. A m2 test

was used to compare groups with respect to each of the ECG

criteria frequency. In this subgroup of 147 patients, we also

correlated the mean wall thickness with the overall ECG score.

A P value of b.05 was considered significant.

Left ventricular diastolic diameter. In a similar manner to

the analysis of wall thickness, 2 groups of markedly differentleft ventricular diameters were also created from the subset

with an LVM b400 g. Group C was selected from patients with

a left ventricular diameter of b50 mm and group D from

patients with a left ventricular diameter of N60 mm. A m2 test

was used to compare groups with respect to each of the ECG

criteria frequency. In this subgroup of 331 patients, we also

correlated the left ventricular diameter with the overall ECG

score. A P value of b.05 was considered significant.

Left ventricular mass. To evaluate the effect of an

increasing LVM on the 4 ECG criteria performance, we

compared the frequency of each of the 4 ECG criteria,

described above, as they occurred in each of the 3 LVM groups

(see group subsets described above). A m2 test was used to

compare the presence of each of the ECG criteria with respect

to each of LVM groups. In the entire study cohort of

611 patients, we also correlated the continuous variables of

LVM with the corresponding ECG score. A P value of b.05 was

considered significant.

ResultsPatient characteristics

We obtained ECGs and echocardiograms on 608

patients. The sex distribution of this cohort was 47%

men and 53% women. The mean age of the study group

was 56 years. The patients with the lowest LVM ( b400 g)

had a mean age of 58 years. With increasing LVM, the

mean age declined such that, at the highest level of LVM

( N600 g), the mean age was 52 years ( P b .01).

Echocardiographic findingsIn the entire patient cohort, our measurements of the

left ventricular septal and posterior wall thickness

ranged between 13 and 30 mm with a mean value of

16 mm. All patients exhibited an abnormal wall

thickness because this was the primary requirement for

entry into the study. The left ventricular end-diastolic

diameter ranged between 25 and 74 mm. with a mean

value of 49 mm. The LVM ranged between 134 and

1006 g, with a mean value of 460 g.

The relationship between left ventricular mass, wallthickness, and diastolic diameter

Our patient cohort consisted of 3 groups, character-

ized by increasing LVM (see Table I ). Group I

(290 patients) had a mean LVM of 318 g; group II

(255 patients) had a mean LVM of 480 g, and group

III (63 patients) had a mean LVM of 718 g.

From groups I to II and III (with increasing LVM), the

mean left ventricular wall thickness progressively in-

creased from 15 to 17 mm and 18.5 mm, respectively.

The mean left ventricular diastolic diameter also

progressively increased from 41 to 51 mm and then to

60 mm in those 3 groups with increasing LVM.

Effect of increasing LVM on individualelectrocardiogram criteria An increase in the echocardiogram-derived LVM had a

significant effect on all 4 ECG criteria (see Figure 1 ). The

differences in the frequency of each of the 4 criteria were

statistically significant at a P value of b.001 or greater. Voltage criteria. The frequency of the occurrence of

voltage criteria for LVH increased from 52% to 66% to

83% as LVM progressively increased from groups I to III

( P b .0001).Left atrial abnormality. As LVM increased through the

3 groups, the frequency of left atrial abnormality also

rose from 46% to 59% and then to 68% ( P b .001).

Table II. Relationship between number of criteria for LVHpresent on the ECG and LVM

Romhilt and EstesECG score Mean LV mass (g) P value*

0 3461-3 365 (0 vs 1-3) = .114-6 410 (1-3 vs 4-6) V .0017-9 452 (4-6 vs 7-9) V .00110 501 (7-9 vs 10) V .003

*t Test.

Figure 1

0

10

20

30

40

50

6070

80

90

100

< 400 g

(n = 290)

4-600 g

(n = 255)

>600 g

(n = 63)

LV Mass

% ST and/or T abn

% LAE

% Voltage abn

% QRS delay % P

a t i e n t s

With increasing LVM, there was a significant increase in the number of patients demonstrating the presence of each of the 4 criteria on theECG ( P b .001 for LAE and P b .0001 for the other 3 criteria). LV ,left ventricle; LAE , left atrial abnormality; abn, abnormality.


Volume 149, Number 4Budhwani, Patel, and Dwyer 711



ST-T changes. In a similar fashion, the ST-T wave

changes also were more frequent with increasing LVM.

We found a change from 55% in group I up to 95% in

group III ( P b .0001).QRS duration. Finally, the presence of QRS prolonga-

tion was also significantly increased from 42% in group I

up to 70% in group III ( P b .0001).

Relationship between electrocardiogram score and left ventricular mass

When a zero score was present from the ECG, the mean

LVM was 346 g (see Table II ). When the greatest score

(10) was present on the ECG, the mean LVM was 501 g.

With each graduation above the 0-to-3 ECG score, the

difference was significant at a P value of b.001, b.001, and

b.003, respectively. In addition, in all 608 patients, we

demonstrated a significant correlation ( r = 0.35) of the

Romhilt-Estes ECG scores with the LVMs ( P b .0001).

Effect of left ventricular wall thickness on

electrocardiogram criteriaFrom our blow Q LVM patients ( b400 g), we created

2 subgroups. Group A included 109 patients with a septal

and posterior wall thickness between 14 and 15 mm, and

group B had 38 patients with 1 wall thickness N17 mm

(see Figure 2 ). The 2 subgroups had a similar and

statistically not different mean LVM (313 vs 345 g).

In the analysis of frequencies of each of the 4 ECG

criteria between the group with the least increase in

wall thickness and the group with the greatest increase

in wall thickness, we observed that there were no

significant differences in the frequency of any of the

4 ECG criteria for LVH between the 2 groups. Wall

thickness, per se, did not influence ECG results. The

correlation between wall thickness and the ECG score in

this subgroup was poor ( r = 0.07) and not statistically

significant ( P = .34).

Effect of left ventricular diastolic diameter onelectrocardiogram criteria

In a similar manner to the description above, we

selected from the blow Q LVM ( b400 g) patients and

created 2 groups (see Figure 3 ). Group C included

263 patients who had a left ventricular end-diastolic

diameter of b50 mm, whereas the 68 patients in group D

patients all had a diameter of N60 mm. These 2 sub-

groups had a similar mean LVM (310 vs 276 g) that was

not statistically different.

In our analysis, there were no significant differences

between the 2 groups, in the frequency of any of the

4 ECG criteria except for the QRS prolongation. The

frequency of QRS prolongation (64% vs 40%) was

significantly ( P b

.001) greater in the group with increased diameter despite a somewhat lower mean

LVM. Except for QRS duration, left ventricular diameter

did not influence ECG results. The correlation between

left ventricular diameter and the ECG score in this

subgroup was also poor ( r = 0.07) and not statistically

significant ( P = .23).

DiscussionDespite the unquestioned demonstration that the

M-mode and 2-dimensional echocardiogram provide

us with a satisfactory bgold standard Q for the determi-

Figure 2

44 424239

6258

29

45

0

10

20

30

40

50

60

70

Wall Thickness 14 mm

LVM = 313 g (n = 109)

Wall Thickness = 17-27 mm

LVM = 345 g (n = 38)

% P

a t i e n t s Voltage

LAE

ST - T abn

QRS Delay

GROUP A GROUP B

There is no significant effect of increasing left ventricular wall

thickness on each of the 4 ECG criteria for LVH in the presence of similar LVM in each group.

Figure 3

49

43 4645

55

6865*

40

0

10

20

30

40

50

60

70

80

LV diameter 50 mm

LVM = 310 g (n = 263)

L V d iamet er 60 m m

LVM = 276 g (n = 68)

% P

a t i e n t s Voltage

LAE

ST - T abn

QRS delay

* P ≤ .001

GROUP C GROUP D

There is no significant effect of increasing left ventricular walldiameter on 3 of the 4 ECG criteria for LVH in the presence of similar

LVM in each group. Asterisk indicates that the effect of increasing left ventricular wall diameter significantly increased the frequency of aQRS delay ( P b .001).





nation of LVH, there have been continuous efforts to

improve both the performance of the ECG and our

understanding of its limitations. The ECG is relatively

inexpensive and easy to perform, insuring its role as an

excellent screening tool for the diagnosis of LVH. In this

vein, we carried out this analysis to improve theunderstanding of which anatomic features of the

remodeled left ventricle influence the ECG criteria that

are used in the diagnosis of LVH.

Anatomically, LVH is characterized by an increase in

muscle mass, and mass is a function of both left ventric-

ular chamber size and left ventricular wall thickness.

The relative importance of wall thickness and ventricu-

lar diameter, vis-a-vis LVM, in the determination of the

ECG abnormalities has not been previously examined.

This study was designed to examine the relation

between these 3 anatomic characteristics of LVH and the

4 ECG criteria used for the diagnosis of LVH. The ECG

criteria we used were those in common usage andincluded voltage, left atrial abnormality, prolonged QRS

conduction time, and repolarization abnormalities.

Echocardiography is the procedure of choice for the

quantitation of left ventricular wall thickness, diameter,

and mass.4 W e used this technique as our reference

standard for these measurements.

Our patient population was selected based on the

presence of 1 definitive aspect of LVH on the echocar-

diogram, that is, an abnormal left ventricular wall

thickness. As a result of this inclusion criterion, we

anticipated that all patients would have an increased

LVM. In fact, our cohort demonstrated a wide range of

abnormal echocardiographic changes such as a left

ventricular wall thickness between 13 and 30 mm, end-

diastolic dimensions from 25 to 74 mm, and an LVM

between 134 and 1006 g. Although we lacked the data

(height and weight) to normalize the LVM, the purpose

of the study was to examine the effect of the mass on the

ECG rather than to establish normal versus abnormal,

which is the primary value of normalizing such data.

The interpretation of LVH on the ECG has usually

been approached as a dichotomous interpretation

(either present or not present). Of all the ECG criteria

for LVH, increased voltage has always been a necessity

for the consideration of a diagnosis of LVH. It is theonly ECG abnormality that has been uniquely linked

with LVH. As a result, the sensitivity for the diagnosis

of LVH, by the ECG, rests with the presence of

increased voltage. The sensitivity for detection of LVH

in our patient population, based on the overall

frequency of abnormal voltage, was 61%. This per-

centage compares favorably with previously published

studies.10,14 A number of efforts have been published

that attempt to improve sensitivity through differing

methods of estimating QRS voltage.14-16 Also, the effect

of external factors on v oltage, such as body habitus,

has also been examined.17

The presence or increased frequency of the other

ECG criteria for LVH, beyond voltage, usually has the

effect of improving the specificity of the diagnosis

when combined with increased voltage. Therefore, any

factors that influence the frequency of the ECG criteria

will logically also affect either sensitivity or specificity.It is in this light that we analyzed the impact that

anatomic features of LVH would have on the ECG

criteria. There is minimal information in the literature

on the independent effect that left ventricular wall

thickness, size, or mass has on the frequency of the

ECG criteria. This in turn could influence the sensitivity

and specificity for the ECG diagnosis of LVH.18,19

Unexpectedly, our analysis demonstrated that the

extent of increase in LVM was the only anatomic

abnormality that influenced the frequency of all 4 ECG

abnormalities and correlated with the total ECG score. In

contrast, neither wall thickness or ventricular diameter

significantly affected the frequency of the appearance of the ECG criteria. We found that, as LVM increased, the

frequency of each of the 4 ECG criteria correspondingly

increased. By example, at the lowest level of LVM

( b400 g), abnormal voltage occurred in only 52%,

whereas at the highest tertile of LVM ( N600 g), the

frequency of abnormal voltage was 83%. Therefore, the

sensitivity of detecting increased LVM improved pro-

portionally to the degree of increased mass.

In the same manner and to the same degree, we found

that an increased occurrence of left atrial abnormality,

QRS conduction time, and ST-T repolarization abnormal-

ities was associated with an increasing LVM. Therefore,

one would anticipate an improved specificity, as well, as

the mean LVM increased. In the highest tertile of LVM,

the frequency of the appearance of left atrial abnormal-

ity (68%), QRS conduction time (70%), and ST-T changes

(95%) was significantly greater than in the patients in

the lowest tertile of LVM, who had mean rates of 46%,

42%, and 55%, respectively. In support of the above

observations, we also observed that 19% had a normal

ECG in the lowest tertile group, whereas a normal ECG

was not present in any patient in the upper tertile group

for LVM.

These findings can explain the variability in the

sensitivity and specificity of the ECG in the detection of increased LVM in previous studies. Based on our data,

we would anticipate that a population under study with

a large increase in LVM (renal insufficiency, idiopathic

cardiomyopathies, and severe aortic valvular disease)

would be expected to show both a higher sensitivity and

specificity than a population consisting of disorders

associated with lower LVM changes. We suggest that

expectations, for the performance of the ECG in the

detection of increased LVM (LVH), should be moderated

accordingly. One might anticipate that clinical disorders,

commonly associated with large increases in LVM, will

reflect LVH on the ECG, on average, in 70% to 80% of the


Volume 149, Number 4Budhwani, Patel, and Dwyer 713



patients. On the other hand, patients with the lowest

increases in LVM will often go undetected. Detection of

small increases in LVM would be best approached with

echocardiographic studies.

In our study, we also examined the effect that

increasing severity of wall thickness and ventricular diameter has on the frequency of the 4 ECG criteria when

LVM is held relatively constant. We found, in both

analyses, that neither the increase in wall thickness or

ventricular diameter correlated with the ECG score nor

resulted in a significant change in the frequency of any of

the 4 ECG criteria. There was 1 exception to that general

conclusion. We did observe that a prolonged QRS

conduction time occurred significantly more often with

increased left ventricular size, although LVM was similar.

In addition to our observations of the effect that LVM

has on the ECG, we also demonstrated that as the

number of criteria increases on the ECG, the LVM

significantly increases. For example, when voltagecriterion is the only criterion present on the ECG, the

average LVM is 365 g, whereas the presence of all

4 criteria on the ECG is associated with a 37% greater

mean LVM at 501 g. From this, we conclude the ECG

indicators of LVH are reasonable representations of the

severity of LVM. Because of the wide range of LVM

within each ECG grouping, these findings are only

reflective of the group and cannot be applied with any

assurance to the individual patient.

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reference to preponderance of one or other chamber. Heart 1914;5:367.

2. Scott RC, Seiwert VJ, Simon DL, et al. Left ventricular hypertrophy—a study of the accuracy of current electrocardiographic criteria whencompared with autopsy findings in one hundred cases. Circulation1955;11:89-96.

3. Rosenfeld L, Goodrich C, Kassenbaum G, et al. The electrocardio-graphic recognition of left ventricular hypertrophy. Am Heart J1962;63:731-42.

4. Devereux RB, Casale PN, Eisenberg RR, et al. Electrocardiographicdetection of left ventricular hypertrophy using echocardiographicdetermination of left ventricular mass as the reference standard. J AmColl Cardiol 1984;3:82-7.

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14. Murphy ML, Thenabadu PN, de Spyza N, et al. Sensitivity of electrocardiographic criteria for left ventricular hypertrophy accord-ing to type of cardiac disease. Am J Cardiol 1985;55:545- 53.

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Electrocardiographic Diagnosis of Left Ventricular Hypertrophy- The Effect of Left Ventricular Wall Thickness, Size, And Mass on the Specific Criteria for Left Ventricular Hypertrophy