QUANTIFICATION OF ORTHOGONAL ECG/Kan

3. 4. 5.

6. 7. 8.

stimulation: A method of demand QRS-blocking pacemaker suppression in the study of arrhythmias. Am Heart J 81: 20, 1971 Center S, Berger RA, Tarjan P: The diagnosis of acute myocardial infarction in patients with permanent pacemakers. Arch Intern Med 127: 932, 1971 Voukydis PC, Shulman AN, Cohen SI: Unmasking of slow intrinsic ventricular excitation by magnetic inhibition of R-wave inhibited demand pacemakers. Chest 67: 304, 1975 Varenne A, Barold SA: Therapeutic usefulness of chest wall stimulation in patients with demand pacemakers. J Electrocardiol 8 (1): 91, 1975 Barold SS, Gaidula JJ: Evaluation of normal and abnormal sensing function of demand pacemakers. Am J Cardiol 28: 201, 1971 Morse D, Parsonnet V, Cuddy TE, Escher DJW: External radiomagnetic control of pacer rate and power. (abstr) Chest 64: 403, 1973 Morse D, Samuel A, Fernandez J, Lemole G, Parsonnet V: Preliminary

9.

10. 11.

12. 13.

et

al.

31

experience with the use of a programmable pacemaker. Chest 67: 544, 1975 Chatterjee K, Harris A, Davies G, Leatham A: Electrocardiographic changes subsequent to artificial ventricular depolarization. Br Heart J 31: 770, 1969 Gould L, Sundaram K, Venkataraman K, Goswami MK, Gomprecht RF: Pacemaker induced electrocardiographic changes subsequent to myocardial infarction. Chest 63 (5): 829, 1973 Takagi M, Ichinose S, Ashida D, Tanaka R: Subthreshold chest wall stimulation in the management of digitalis intoxication in patients wearing ventricular-inhibited demand pacemaker. Jap Circ J 36: 779, 1972 Takagi M, Ichinose S: Subthreshold chest wall stimulation as a method of management of demand pacemaker. Jap Circ J 38: 131, 1974 Driller J, Barold SS, Parsonnet V: Normal and abnormal function of the pacemaker magnetic reed switch. J Electrocardiol 9: 283, 1976

Quantification of the Normal Frank

and McFee-Parungao Orthogonal Electrocardiogram at Ages Two to Ten Years JEAN S. KAN, M.D., JEROME LIEBMAN, M.D., Moo HEE LEE, M.D., AND ALLAN WHITNEY, M.S.

SUMMARY A quantification of the Frank and McFee-Parungao orthogonal electrocardiogram of 175 normal children, ages 2-10 years is presented. There are significant differences in age groups 2-5 and 6-10. The QRS voltages of the younger group demonstrate 1) greater Z anterior, 2) greater initial X right, 3) greater terminal X right, 4) smaller Y inferior, and 5) the T vector is oriented more posteriorly. There are significant differences between the two lead systems. 1)

Frank spatial voltages are 70% of those of McFee. 2) Frank X left is 70% of McFee, but terminal X right is 75% and initial X right is 60% of McFee. 3) Frank Y inferior is 78% of McFee, but initial Y superior is 83% and terminal Y superior 61% of McFee. 4) Frank Z anterior is 64% and Frank Z posterior is 70% of McFee. 5) In terms of ratios the Frank is relatively less inferior, about equally posterior and more terminally right. 6) The T vector is more posterior in Frank than McFee.

STANDARD ELECTROCARDIOGRAPHY is known to be relatively inaccurate, yet it remains the system of choice for recording the summation of electrical potentials on the surface of the human. The distortion between the myocardial cell and the surface is considerable for many reasons; and this is so with any surface technique.' However, there is much theoretical and practical evidence that orthogonal "dipolar" electrocardiography is less distorted and can better reflect cardiac events than does standard electrocardiography.2'-0 Therefore, it is necessary to continue to collect a detailed normal data base from various age groups utilizing the best available practical lead systems. The Frank'1 and McFeeParungaol" orthogonal electrocardiographic lead systems, on both theoretical and practical bases, appear to have the best chance of becoming standard. Only limited data are

included only 105 children, but it provided a model for complete linear, circular and spherical quantitation and statistical analysis of electrocardiographic data. More recently published was an analysis of 166 adolescents between the ages of 11 and 19 years, which included 57 subjects from the previous report.37 The present study is of 175 children, ages two to ten years, including 48 of the original 105.

available for adults'3"19 and children.20-35

We have published a very detailed quantification of both the Frank and McFee-Parungao orthogonal electrocardiographic systems from age two to 19 years.36 That study From the Departments of Pediatrics and Biometry, Case Western Reserve University School of Medicine and University Hospitals, Cleveland, Ohio. Address for reprints: Jerome Liebman, M.D., University Hospitals of Cleveland, Cleveland, Ohio 44106. Received May 6, 1976; revision accepted July 26, 1976.

Material and Methods We studied 175 normal children with an approximately equal number of blacks and whites. The Frank and McFee vectorcardiograms were obtained using methods previously described with the subjects in the supine position. The Hart PV3 vectorcardiograph was used for the first 48 children with the vector trace interrupted every 0.002 sec. A specially constructed Electronics for Medicine (E for M) vectorcardiograph was utilized for the next 127 subjects. Simultaneous X,Y,Z scalars could be taken alone or with any two loops (horizontal, sagittal, frontal). With the E for M machine, the vector trace was interrupted both every 0.002 sec for double loops and 0.001 sec for single loops. The T wave was analyzed only for the maximal planar and spatial vectors. The P wave was not measured. The data were analyzed with the aid of an IBM

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32

CIRCULATION TABLE 1.

VOL

55,

No 1, JANUARY 1977

QRS Durations Dulration anterior Mean SD

Total duration SD Mean

N Frank lead system (1F) 23 M 2-5 M 6-10 60 M 2-10 83 F 2-5 29 F 6-10 63 F 2-10 92 T 2-5 53 T 6-10 123 T 2-10 175 T 2-19* 341

.011 .011 .012 .008 .009 .009 .009 .010 .010 .011

.062 .069 .067 .061 .064 .063 .061 .066 .065 .068

Duration anterior Duration total SD Mean

Duration right Duration total SD Mean

Duration terminal right SD Mean

.026

.42

.06

.021

.010

.33

.13

.027

.39

.08

.023

.011

.33

.13

.027

.40

.08

.023

.33

.13

.025

.42

.07

.019

.011 .007

.32

.10

.027

.42

.10

.018

.010

.27

.14

.026

.42

.09

.018

.009

.29

.13

.026

.42

.07

.020

.008

.32

.027

.41

.09

.020

.011

.30

.14

.026

.41

.08

.020

.010

.31

.13

.028

.42

.11

.020

.011

.28

.14

.43 .41 .42 .41 .42 .42 .42 .42 .42 .42

.05 .08 .08 .09 .08 .08 .07 .08 .08 .11

.012 .013

.34

.012

.33 .29 .24 .26 .32 .28 .29 .27

.11

lcFee lead system (1 11) I4 4 F F F T T T T

2-5 6-10

.064 .069 .067 .060 .064 .063 .062 .066 .065 .068

23 60 83 29

.012

.027

.014

.028

.013 .007

.028 .025 .027 .026 .026 .027 .027 .029

.004 .007 .006

2-10 2-5 6-10 2-10 2-5 6-10 2-10 2-19*

92 53 122 175 341

*In

of the tables, data for the total of 341 children, aged 2-19

some

63

.009

.009 .010 .012 .011 .011

.006 .007 .006 .005 .007 .007 .008

1620, Mod 2 Computer in a manner described previously. The linear measurements were reported in terms of mean and standard deviations, but because of inherent skewing in all electrocardiographic data, percentiles were also calculated. These were the 5th (Po5), 10th (PiO), 50th (P50), 90th (P,O) and 95th (P95), to which have been added the 21/2th (P.2,5) and 97½/2th (P,7,.). In general, it is recommended that an abnormally low or high voltage be diagnosed when it is below the Po, or above the P,5 value, though some may prefer the Po2.5 or Pg7.5 values. The standard linear statistical methodology cannot be used. The methodology is as previously described.38 Results In analyzing abnormal electrocardiographic data, it is still not yet known which of the multiple parameters are most

TABLE

Quantification of the normal Frank and McFee-Parungao orthogonal electrocardiogram at ages two to ten years.

QUANTIFICATION OF ORTHOGONAL ECG/Kan 3. 4. 5. 6. 7. 8. stimulation: A method of demand QRS-blocking pacemaker suppression in the study of arrhythmi...
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