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Tricuspid atresia An electrocardiographic study
Tricuspid
atresia
An electrocardiographic
study
Andrew Y. Somlyo, M.D.* Katherine II. Halloran, M.D.** New York, N. Y.
T
he presence of left axis deviation in patients with cyanotic congenital heart disease is considered to be highly suggestive of the diagnosis of tricuspid atresia.’ X pattern of left ventricular predominance in precordial leads further supports this diagnosis.” In recent years an increased number of cases of this malformation have been reported, including a smaller but nonetheless sizable group of cases in which the electrocardiograms do not display left axis deviation. The present study attempts a reappraisal of the electrocardiographic findings in tricuspid atresia, with particular attention to the significance of normal or right axis deviation. The presence in our series of several patients who were undergoing palliative operations has also enabled us to observe some of the postoperative electrocardiographic changes in cases of this malformation. Material
and
methods
The present study includes our series of 17 cases of tricuspid atresia, in which the diagnosis was verified by angiocardiogrnphy or postmortem examination, and 73 autopsied cases collected from the literature. In some, sufficiently detailed information was not available for inclusion From
in every phase of this study, which fact accounts for the variable number of patients included in our findings. Ten of our patients had undergone operations; six of these operations were aortopulmonary anastomoses, three were subclavian-pulmonary artery anastomoses, and one was a superior vena cava-pulmonary artery anastomosis. In one patient with aortopulmonaqanastomosis the atria1 septal defect was enlarged at the time of a second operation. Electrical axis was defined according to the criteria of the New York Heart Association” : 3 normal electrical axis, +30 to +90 degrees; left axis deviation, +29 to -90 degrees; and right axis deviation, +91 to +180 degrees. In a few cases collected from the literature, axis deviation was stated to be present, but the authors did not assign a numerical value to it. The anatomic types of tricuspid atresia were subdivided according to the criteria of Edwards and BurchelF as modified by Keith, Rowe and Vlad6 (Table II). Results 1. Our .suics. The following electrocardiographic findings were encountered in our 17 cases of tricuspid atresia (Table I ).
the Departments of Medicine and Pediatrics, and the (‘ardiovascular Laboratory, C~,lumbia-PresbJ,trrian Medical Center, New York. S. Y. Received for publication July 14, 1961. *Assistant Physician in Medicine. Columbia-Presbyterian Medical Center. New \-ark. S. Y.: Research Fellow of the New York Heart Association. Present address: i)epartment of Riomedical Engineering. Ihxrl Institute (bf Tcchnology and Presbyterian Hospital, Philadelphia, Pa. **Visiting Fellow in Pediatrics, Babies Hospital. Columbia-Presbyterian Medical Center. New York. N. Y.; Meyer Berger Fellow of the New York Heart Association. Present address: T~epartment of Pt~dixtricr, Yale I.nivrrsity School of Medicine, liew Haven, Corm.
171
172
Somlyo and Halloran
Table I. Summary of electrocardiographic findings and clinical and necropsy data in 17 patirnt.~ with tricuspid ntresia Precordial Axis (de- / PI1 grees)~ (mv.) A. No axis deviation 1. D.B. 2. N.M. 3. E.B. 4. J.R.
7. A.B.
B. Left axis deviation 9.N.G. 10. H.P. 11. R.Q. 12. I.S. 13. J.G. 14. M.E. 15. J.W. 16. N.S.
L’s
rs rS rS RS rS rs rS rS
+75 $70
.15 .25 .3O .45 .60
.16 .09 .ll .lO .14
rS rSr’ rs rS rs
-25 -30 +15 -20 -30 -50 -50 -60 -80
.40 .40 .45 .35 30 .40 .40 .35 .40
.lO 10 110 .09 .13 .lO .12 : 14 16
rS rS rS rS rs rS rsR’ rS
RqR qR qR KS Rs R Rs
.30 .40
.17 .16
rsR’ Rs
Rs qR
+60 +50 +40 +40 +65
-80 17. ES.
/
.lO 12 109 .12 .12 .12 14 :I6
$60 8. 50.
I;
.25 .20 .15 10 :40 .35 30 .70
+60 +45 +35 +60
-t-60 5. D.S. 6. K.B.
P-R (sec.)
pattern
0
j
V,
1 i
j
I
! &I + 1 Rvs
Ii qR qK qI<
1 2 5 5 7
qI< Rs
KS qR qR (IR
qR
da)day da)da> nlo. *
4 wk. 10 wk. 6 mo.*
RS Rs
qR
I Age at time of ECG
4 4”.* 5 nlo.
28 26 52 26 68
3 yr.* 6 mo. 3 yr.*
1 wk. wk. 1 mo. 2 mo. 3 ,110. 3 mo.
58 46 28 28 52 26 20 62 24
6
2 yr.* 3 yr. 3 yr.
24 18
13 4”. 4 yr.
Swgery
I
/ Surziz~al! I
No
Anatomic type
IXed Died Died 1,ived
IA ZC 1C 1
I>ietl I.ivetl
LC I
I’otts
Lived
1
Potts
I~ivetl
1
NO
Died Died Died Died Lived Lived
1B 2c 2B 1B I 1
Blalock SVC-RPA anastomosis
Lived Lived
1 1
Blalocli
Lived
1
NO h-0 Potts
NO
Potts (6 1110.) AS13 eolargemerit (3 yr.)
NO
Blalock No Potts Potts
*Postoperative
record.
p WAVE. A P wave which exceeded 2.5 mm. in Lead II was found in 14 patients (82 per cent), and it was considered to be peaked in at least one electrocardiogram in every case. Minor notching of this complex was present in 4 cases, with the first peak being taller in each. A diphasic P (plus-minus) was present in Lead V1 in 14 cases. Among the 8 cases in which there were follow-up electrocardiograms for 6 months or longer prior to operation, the P wave increased in size by 1 mm. or more in 6. Initially positive P waves in Lead V1 became diphasic in subsequent records in 2 cases. After palliative operations the P wave decreased in size by 1 mm. or more in 3 of the 7 patients in whom subsequent electrocardiograms were available,
remained the same in 2, and increased in size in 2. In one of the latter patients the atria1 septal defect was later enlarged surgically; after this procedure there was a 4.5-mm. decrease in the height of the PII wave (Fig. 1). P-R INTERVAL AND SEGMENT. The P-R interval was prolonged in 2 of the 17 cases (12 per cent) and measured less than 0.11 second in 4 (24 per cent). The P-Rsegment measured 0.04 second or less in each case with a shortened P-R interval, and in 3 cases with a normal P-R interval. AXIS QRS. Left axis deviation was present in 9 of our cases (53 per cent), and a normal electrical axis in 8; the latter will be discussed in detail subsequently. Right axis deviation was not found in our patients.
Tricuspid atresia: ECG study
Serial electrocardiograms were available over an interval of 8 months or longer in 8 patients. During the period of follow-up, 7 of these patients underwent anastomotic procedures. The electrical axis remained unchanged throughout the period of followup in 6. In one patient a 35-degree shift to the left occurred preoperatively, followed by a 25-degree shift to the right after subclavian-pulmonary artery anastomosis. In children this degree of change in the axis in isolated records is of dubious significance, as illustrated by the other patient, whose electrical axis changed back and forth by as much as 40 degrees prior to operation (from +70 to +30 to +SO degrees in three electrocardiograms taken during a period of 3 months). PRECOKDIAL QRS. In Lead V1, rS coml)lexcs were present in 13 cases (77 per Table II. Anatomic
173
cent). In one patient an rSr’ pattern which was present at 5 months of age changed to the rS type after an aortopulmonary anastomosis 17 months later. An rSR’ or RS pattern was seen in one case each, and KS was present in one patient with malrotation of the heart. In Lead Vs, qR complexes were present in 11 cases (65 per cent), KS in 4, and R in 2. The precordial-voltage criteria for left ventricular hypertrophy which were suggested by Nadas6 to be applicable to children (SV, plus RV5 > = 45 mm.) were fulfilled in 9 patients. The intrinsicoid deflection over the left precordium was delayed beyond 0.04 second in only one of our cases. ST-T CHANGES. An upright T wave over the right precordium was found in 8 of 13 patients in whom electrocardiograms were available before 6 months of age. In only
diagnosis and electrical axis: our series and the literature I
Number
1 Axis
TrPe
__~____ Our
series
Ventricular sepal defect
of cases .__~Liternturet
---~ 1
Present
_.._._ _-I
Total
Absent 1
\Vith no transposition A. Pulmonary atresia
1.
Left NOW?
U.
C.
2.
Pulmonary hypoplasia, subpulmonary stenosis
Ko
pulmonary
hypoplasia
Right Left Sane Right Left None
B.
Pulmonary stenosis
or subpulmonary
Left None Right
C.
Large
Left N011e
Right
3IO.2L.22
12 (Cl 1
24* 1 (small)
9* 1 (absent septum)
4 4 2 2 2
6 4 2 28 3 0
2
12 1
1
1 2
1 CD) 41.21.31 3”,9.20
s
73
5 0 0 8 6 3 81
*Other
t.i=
cases not indicated by authors. 1. 7. 11, 13. 19. B = References 7, 19. 21. 36, 37.
2’3.21 26 (B)
2
2 1 0
Left None Right
Totals
j1.23,?8
0
atresia
artery
2
6 (.XL\)
Right With transposition A. Pulmonary
pulmonary
1
References
References
7. 18. 19. 21. 3r). 31, 32. C =
References
7, 12, 13, 17. 18, 21, 24. 33, 34, 3,s. D zz
174
Somlyo and Halloran
4 of these was associated fattening OI inversion of the T wave present in Leads I, ~VL, or Ve. Fifteen patients had electrocardiograms recorded while they were not receiving digitalis; in 11 of these, depression of the S-T segment and/or flattening or inversion of the T wave were present in Leads 1, aVI,, V5, and Vg. In one patient with vertical electrical position of the heart these changes appeared in Leads II, II I, and ~VF. After shunt procedures the ‘I wave became upright in Leads VS or 1’6 in 4 of the 6 patients who were not receiving digitalis (Fig. 2).
2. Factors ageding the presence oj normal and right ask deviation: our series and thr literature. A total of 81 autopsied cases, including 73 collected from the literature, was analyzed to determine the anatomic features which affect axis deviation (Tables I and II). Left axis deviation was present in 61, normal axis in 15, and mild right axis deviation in 5. No documented case of right axis deviation of more than +llO degrees was encountered. Eight of our cases in which the diagnosis was made b>angiocardiography were also included in part of the study dealing with the effects of age on axis deviation (Table III ). EFFECT OF AGE (TABLE III). Right axis deviation or a normal axis was not limited to the patients in early infancy. The average age of these patients was 8 months (range of 1 day to 5; 5 years), and 13 of them were over 3 months old. In serial tracings, a normal axis did not shift to the left with increasing age. Conversely, a left axis was observed frequently in the first month of life, in one case as early as 24 hours of age. ANATOMIC
SCNGROLIPS
(TABLE
II).
‘I‘he
majority of cases in which there was a normal axis were among those associated with pulmonic atresia (Type L4j or transposition of the great vessels with large pulmonary artery (Type 2C) (Fig. 3). Cases of mild right axis deviation were present in either of these subgroups and in none of the others. Three instances of normal axis were present in the cases of common type of tricuspid atresia, that associated with a normal origin of the great vessels, subpulmonic stenosis, and a hypoplastic pulmonary artery (Type 1R). The presence of an in-
tact ventricular septum in 2 of these 3 may be significant, since in 24 of the 26 cases in this group which displayed left axis deviation a ventricular septal defect was present. 1)ISTRIRVTION
OF
AXIS
IN
TYPES
IA
.\NI)
2c (TABLE II). Twenty-nine cases in these subgroups were studied. ANormal or right axis deviation was present in 15 (52 per cent); 10 showed no axis deviation, and in 5 there was right axis deviation. Discussion The characteristic electrocardiographic findings in tricuspid atresia (Fig. 4) have been described by previous authorsS”‘” The most common abnormality of the I’ wave is the presence of a tall, peaked Prr, indicative of right atria1 enlargement. Minor notching of this complex and, more frequentll-, biphnsic plus-minus type of I’ waves over the right precordium provide evidence of additional left atria1 enlargement. Prolongation of the P-K interval was observed by Donzelot and co-workers” in 14 per cent of their cases and was present in 2 of our cases (12 per cent). (:omplete atrioven tricular block was present in one reported cast‘.!’ Conversely, Keith, Rowe and \%d5 commented upon the absence of the P-R segment in 50 per cent of their patients, but did not include measurements of the P-Ji interval. This interval measured 0.11 second or less in duration in 24 per cent of our patients and was associated with QRS complexes of normal duration. A P-R segment of 0.04 second or less was present in all of our patients with shortened P-R intervals, and in 3 lvith normal P-R intervals. The QRS morphology in precordial leads usually reveals evidence of left ventricular predominance, manifested by predominantly negative complexes over the right precordium and positive complexes over the left. Right ventricular predominance is exceptional, but in one illustrated case an Rs complex was present in Lead V*K.“’ Two other cases were described as showing right ventricular enlargement.“~‘” Right bundle branch block was present in one of our cases, and in one case reported bl Chiche.13 Equiphasic RS complexes in I,ead j,rl are next in frequency to the more common rS pattern seen in this leatl.7,‘,’
Fig. 2. Case 4, J .K. I’recordinl leads. .4, Age mosis. B, Age 7 months, after the anastomosis. right in left precordial leads after operation.
Fig. 3. Case Type 2C.
2, N.M.
Age
2 days.
iiQRS
+45
10 days, before The previously
degrees.
Case
aortopulmonary inverted T waves
proved
at autopsy
anastoare up-
to be
Somlyo
176
lbble
III.
Electrical
age: our series
,110. mo. mo. mo. yI-. yr. YI-. yr.
axis
correlated
with
and literature Left axis (number of cases)
Bge
1 day-l l-3 4-6 7-12 l-2 3-5 6-10 11-25
and Halloran
6 15 8 5 11 12 3 6
axis (number
Right
of cases) 1 1 1
Normal axis (xumber of cases) 5 2 6 3 2 1
Electrocardiographic evidence of left ventricular hypertrophy in precordial leads was said to be present in every case studied by Keith, Rowe and Vlad,6 but a similar incidence has not been encountered by others.‘0~18 These discrepancies are presumably due to the questionable accuracy and reliability of the various electrocardiographic criteria of left ventricular hypertrophy in children.r5 In our series the voltage criteria of left ventricular hyper-
trophy which were suggested by Sadas” were fulfilled in only 53 per cent of the cases. Furthermore, in our experience these criteria are not sufficiently stringent to exclude false positives. It is evident, therefore, that the anatomic left ventricular h ypertrophy which is invariably present in cases of tricuspid atresia is not uniforml! reflected in the electrocardiogram. The intrinsicoid deflection may be delayed in left precordial leads.6t7 Left bundle branch block is present in about 5 to 10 per cent of the cases.5,7,8J4 Early electrocardiographic studies of tricuspid atresia emphasized the presence of left axis deviation.1s?,16-18 The frequency of this finding has been confirmed in several large series,7~8~‘sand it is estimated to be present in 80 per cent of the cases.5 However, left axis deviation may be found in patients with cyanotic congenital heart disease other than tricuspid atresia.1u~‘g~2” i’iormal axis is considered to be uncommon, and right axis deviation is extremely rare in well-documented cases of tricuspid atresia; both have been the subject of case reports.Yo-YX Taussig’p? has suggested that
Fig. 4. Case 10, H.P. Age 6 weeks. An example of the most common cardiographic pattern in tricuspid atresia. Tall, peaked P waves, left viation, and left ventricular preponderance are present.
electroaxis dc-
Tricuspid
:I balanced electrical axis may be present “very young infants” with tricuspid atresia. The present study indicates, however, that the age of the patient is not a determining factor of the electrical axis in this anomaly. The anatomic significance of normal and right axis deviation in cases of tricuspid atresia has been analyzed previously by Keith, Rowe and Vlad.5 O& findings- confirm the opinion of these authors that no axis deviation is more likely to be present in cases of tricuspid atresia associated with pulmonic atresia (Type 1A) or with transposition of the great vessels with large pulmonary artery (Type 2C). Mild right axis deviation may also be present in either of these groups and is not limited to those cases of Type 2C13r”4 as previously suggested.5 A more important finding of the present study is that, in these two anatomic subgroups, normal or mild right axis deviation is as common as left axis deviation. In rare instances a normal axis but not right axis deviation may be present in cases of other anatomic variants of tricuspid atresia. Although the number of observations is limited, our data suggest that in the most common variety of tricuspid atresia, that associated with subpulmonic stenosis and normal origin of the great vessels (Type IB), the presence of an intact ventricular septum may predispose to a normal axis. Conversely, a ventricular septal defect was present in 24 of the 26 Type 1B patients with left axis deviation. It has been suggested recently that the presence of normal axis in clinically suspected cases of tricuspid atresia may indicate tricuspid stenosis rather than atresia.25 Congenital tricuspid stenosis is, however, frequently complicated by pullnonic atresia and an intact ventricular septum.*3 Since these associated lesions were found to be present in cases of tric.uspid atresia which showed a normal axis or mild right axis deviation, it appears that these lesions may influence the direction of the electrical axis. The occurrence of left axis deviation in tricuspid atresia is generally accepted to be the result of an increased left ventricular muscle mass.26 The theoretical aspects of in
atresia: ECG study
177
the determinants of axis deviation are beyond the scope of this presentation, although the presence of increased right ventricular muscle thickness, with a rudimentary right ventricular cavity, in cases in which there is no axis deviation lends support to this explanation.10s2Z-?4 The association of tall P waves with small atria1 septal defects in tricuspid atresia had been observed by Taussig,” but this correlation is neither quantitative nor sufficiently consistent to be diagnostic in individual cases6F7We are limited by the small number of patients studied before and after palliative operations. In spite of this reservation we find it of interest that in none of our 5 patients with good surgical results did the P wave become taller postoperatively; in 3 of these it decreased in size, probably as the result of a greater fraction of the cardiac output returning to the left atrium. On the other hand, the P wave continued to increase in height in 2 patients who did not improve after shunt procedures. One of these patients improved after enlargement of her atria1 septal defect, with a concomitant decrease in PII. If these findings can be confirmed in a larger number of patients, an increase in the size of the P wave after shunt procedures in tricuspid atresia may be accepted as an indication for enlargement of the atria1 septal defect, in addition to the clinical criteria suggested by previous authors.27 Summary
Electrocardiographic studies in patients with tricuspid atresia are reported with reference to the significance and frequent), of normal and right axis deviation, the factors which affect axis deviation, and the electrocardiographic changes after palliative operations. The common electrocardiographic pattern of tricuspid atresia is reviewed. Left axis deviation, tall, peaked and occasionally notched PII waves, and left ventricular predominance in precordial leads were found in the majority of cases. The P-R interval is usually normal, but either abnormal prolongation or shortening may be present. The lack of consistent electrocardiographic evidence of left ventricular hypertrophy is contrasted with the ana-
178
Somlyo and Haloran
tomic left ventricular hypertrophy which is invariably present. The majority of cases in which there is a normal axis, and all cases in which there is right axis deviation, are associated with either pulmonic atresia or transposition of the great vessels with large pulmonary artery. These electrical axes are as common as left axis deviation among these two subgroups. The electrical axis shows no significant change with age. n’ormal and mild right axis deviation is not limited to earl). infancy in patients with tricuspid atresia. After successful shunting procedures, the height of the P wave tends to decrease; T waves tend to become upright in left precordial leads. It is suggested that an increase in the size of the P wave after shunt operations should be evaluated as a criterion for enlargement of the atria1 septal defect in these patients. We wish to acknowledge Sidney Blumenthal, Dr. A. Dr. Joseph Grayzel, who criticisms in the preparation
the assistance of Dr. Gregory Jameson, and offered many helpful of this manuscript.
10.
11.
12.
13.
14.
15.
16.
17.
REFERENCES 1.
2.
3.
4.
5.
6. 7.
8.
9.
Taussig, H. B.: The clinical and pathological findings in congenital malformations of the heart due to defecti\-e development of the right ventricle associated with tricuspid atresia or hypoplasia, Bull. Johns Hopkins Hosp. 59:435, 1936. Taussig, H. B.: Congenital malformations of the heart, ed. 2, Cambridge, 1960, The Conmonwealth Fund-Harvard University Press. Criteria Committee of The New York Heart Association: Nomenclature and criteria for diagnosis of diseases of the heart, ed. 5, New York, 19.53, New York Heart Association. Edwards, J. E., and Burchell, H. B.: Congenital tricuspid atresia: a classification, Med. Clin. North America 33:1177, 1949. Keith, J. D., Rowe, R. D., and Vlad, P.: Heart disease in infancy and childhood, New York, 1958, The Macmillan Company. Nadas, .A. S.: Pediatric cardiology, Philadelphia, 1957, U’. B. Saunders Company. Neil], C. A., and Brink, A. J.: Left axis deviation in tricuspid atresia and single ventricle, the electrocardiogram in 36 autopsied cases, Circulation 12:612, 1955. Donzelot, E., Durand, M., Metianu, C., and Vlad, P.: L’axe Clectrique normal ou d&i& & gauche dans les cardiopathies congenitales Etude de 29 cas personnelscyanog$nes. inter& diagnostique, Arch. mal. roeur 43:577, 1950. Dickson, Ii. CV., and Jones, I. P.: Congenital heart block in an infant with associated mul-
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24.
25.
26. 27.
tiple congenital malformalions, ;\111. j. I )is. Child. 75:81, 1948. Kreutzer, Ii., Caprile, J. A., Berrc, G. (;., and Becu, L. M. : L’Clectrocardiogramme tlalls I’atrbsie tricuspidienne, Arch. Neal. CocIIr 47:113, 1954. Cooley, Ii. N., Sloan, R. I)., Hanlon, C. I<., and Bahnson, H. T.: Angiocardiography in congenital heart disease of cyanotic type. II. Obserl-ations on tricuspid stenosis or atresia with hypoplasia of the right ventricle. liadiology 54:848, 1950. Blount, S. G., Ferencz, C., Friedlich, A., Mudd, J. G., Carroll, D. G., and Ring, 1~. J.: I’hysiological studies in congenital heart disease. XII. The circulatory dynamics in patients with tricuspid atresia, Bull. Johns Hopkins Hosp. 89:235, 1951. Chirhe, I’.: ctudc anatomique et cliniquc d& atrCsies tricuspidiennes, .Arch. mal. coeur 45:980, 19.52. I’ortillo, B., and Anselmi, G.: :\tresia tricuspidea: cstudio electrocardiographico en 23 cases, .Arch. Inst. cardiol. M&c-o. 29:341, 1959. Scott, Ii. S.: The correlation between the electrocardiographic patterns of ventricular hypertrophy and the anatomic findings, Circulation 21:256, 1960. Rihl, J., Terplan, K., and Weiss, F.: i'bcr einen Fall van Agenesie der Tricuspidalklappe, Med. Klin. 25:1543, 1929. Bellet, S., and Stewart, II. L.: Congenital heart disease: atresia of the tricuspid oritire, Am. J. Dis. Child. 45:1247, 193.1. Brown, J. LV., Heath, L)., Morris, T. I~., and Whitaker, \$T.: Tricuspid atresia, Brit. IIeart J. 18:499, 1956. Gasul, B. M., Fell, E. II.. Marina, J. J., and Davis, C. 13.: Tricuspid atresia: report of 2 cases of young infants with successful operation, Am. J. Dis. Child. 78:16, 1949. Sullivan, J. J., and Mangiardi, J. L.: Tricuspid ntresia with right axis deviation: case report and review, AM. HURT. J. 55:450, 1958. Kroop, I. G., and Grishman, A.: The variability of the electrocardiogram in congenital tricuspid atresia, J. Pediat. 37:231, 1950. Ebel, E. II., Lynswiler. C. I’.. and Moragues, \‘.: Tricuspid atresia with a rudimentary right ventricle, J. Pediat. 39:211, 19.51. Elster, S. I<.: Congenital atresia of pulmonary and tricuspid valves, Am. J. Dis. Child. 79:692, 19.50. Berber, S.. and Salas, 51.: Quoted by Novelo, S., Chait, L. 0.. Zapata Diaz, J.. and Velasquez, ‘1‘. : Atresia pulmonar y estenosis tricuspidea sin romunicaci6n interventricular, .qrch. Inst. c-ardiol. M&co. 21:32.5, 1951. Calleja, 1-I. B., Hosier, D. M., and Kissane, R. \V.: Congenital tricuspid stenosis. The diagnostic value of cineangiocardiography and hepatic pulse tracing, Am. J. Cardiol. 6:821, 1960. Sommers, S. C., and Johnson, J. RI.: Congenital tricuspid atresia, AM. HIXHT J. 41:130, 1951. Blumenthal, S., Brahms, S., and Sussman, >I. L.: Tricuspid xtresia with transposition trf I hc
28. 29.
30.
31.
32.
great vessels; successfully treated by surgery, J. Mt. Sinai Hosp., New York 17:328, 1951. Blamer, H.: Zur Diagnose der Tricuspid Atresia, Ztschr. l&n. Med. X4:313, 1956. Rogers, H. nI., Cordes, J. H., Jr., and Edwards, J. E.: Congenital tricuspid atresia in a boy twelve years of age, Am. J. Dis. Child. 80:427, 1950. Bigardi, D., and Lampertico, P.: Congenital atresia of the tricuspid valve. Clinical and anatomical observations apropos of a case, Minerva pediat. 11:1018, 1959. Aktley, Ii., Oldham, J. S., and Parsons, C.: Congenital tricuspid atresia, Brit. Heart J. 15:287, 1953. Gwee, A. L., and Monteiro, E. S.: Tricuspid atresia, Brit. M. J. 2:No. 5056, 1283, 1957.
33.
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Pearson, H. A., and Cone, T. E., Jr.: Harlequin color change in a young infant with tricuspid atresia, J. Pediat. 50:609, 1957. Miale, J. B., Millard, A. L., Beno, ‘I‘. J., and Custer, G. S.: Congenital tricuspid atresia associated with interauricular and interven tricular septal defects, hr. HEART J. 36:438, 1948. Schaede, A.: Die Tricuspidalatresie, Deutsches Arch. klin. Med. 199:102, 1952. Ohanessian, 0. D., and Rodriquez, M. B.: Congenital tricuspid atresia; report of two cases, A.M.A. Arch. Path. 67:439, 1959. Robinson, A., and Howard, J. E.: Atresia of the tricuspid valve with transposition of the great vessels, Am. J. Dis. Child. 75:57.5, 1948.
atresia
An electrocardiographic
study
Andrew Y. Somlyo, M.D.* Katherine II. Halloran, M.D.** New York, N. Y.
T
he presence of left axis deviation in patients with cyanotic congenital heart disease is considered to be highly suggestive of the diagnosis of tricuspid atresia.’ X pattern of left ventricular predominance in precordial leads further supports this diagnosis.” In recent years an increased number of cases of this malformation have been reported, including a smaller but nonetheless sizable group of cases in which the electrocardiograms do not display left axis deviation. The present study attempts a reappraisal of the electrocardiographic findings in tricuspid atresia, with particular attention to the significance of normal or right axis deviation. The presence in our series of several patients who were undergoing palliative operations has also enabled us to observe some of the postoperative electrocardiographic changes in cases of this malformation. Material
and
methods
The present study includes our series of 17 cases of tricuspid atresia, in which the diagnosis was verified by angiocardiogrnphy or postmortem examination, and 73 autopsied cases collected from the literature. In some, sufficiently detailed information was not available for inclusion From
in every phase of this study, which fact accounts for the variable number of patients included in our findings. Ten of our patients had undergone operations; six of these operations were aortopulmonary anastomoses, three were subclavian-pulmonary artery anastomoses, and one was a superior vena cava-pulmonary artery anastomosis. In one patient with aortopulmonaqanastomosis the atria1 septal defect was enlarged at the time of a second operation. Electrical axis was defined according to the criteria of the New York Heart Association” : 3 normal electrical axis, +30 to +90 degrees; left axis deviation, +29 to -90 degrees; and right axis deviation, +91 to +180 degrees. In a few cases collected from the literature, axis deviation was stated to be present, but the authors did not assign a numerical value to it. The anatomic types of tricuspid atresia were subdivided according to the criteria of Edwards and BurchelF as modified by Keith, Rowe and Vlad6 (Table II). Results 1. Our .suics. The following electrocardiographic findings were encountered in our 17 cases of tricuspid atresia (Table I ).
the Departments of Medicine and Pediatrics, and the (‘ardiovascular Laboratory, C~,lumbia-PresbJ,trrian Medical Center, New York. S. Y. Received for publication July 14, 1961. *Assistant Physician in Medicine. Columbia-Presbyterian Medical Center. New \-ark. S. Y.: Research Fellow of the New York Heart Association. Present address: i)epartment of Riomedical Engineering. Ihxrl Institute (bf Tcchnology and Presbyterian Hospital, Philadelphia, Pa. **Visiting Fellow in Pediatrics, Babies Hospital. Columbia-Presbyterian Medical Center. New York. N. Y.; Meyer Berger Fellow of the New York Heart Association. Present address: T~epartment of Pt~dixtricr, Yale I.nivrrsity School of Medicine, liew Haven, Corm.
171
172
Somlyo and Halloran
Table I. Summary of electrocardiographic findings and clinical and necropsy data in 17 patirnt.~ with tricuspid ntresia Precordial Axis (de- / PI1 grees)~ (mv.) A. No axis deviation 1. D.B. 2. N.M. 3. E.B. 4. J.R.
7. A.B.
B. Left axis deviation 9.N.G. 10. H.P. 11. R.Q. 12. I.S. 13. J.G. 14. M.E. 15. J.W. 16. N.S.
L’s
rs rS rS RS rS rs rS rS
+75 $70
.15 .25 .3O .45 .60
.16 .09 .ll .lO .14
rS rSr’ rs rS rs
-25 -30 +15 -20 -30 -50 -50 -60 -80
.40 .40 .45 .35 30 .40 .40 .35 .40
.lO 10 110 .09 .13 .lO .12 : 14 16
rS rS rS rS rs rS rsR’ rS
RqR qR qR KS Rs R Rs
.30 .40
.17 .16
rsR’ Rs
Rs qR
+60 +50 +40 +40 +65
-80 17. ES.
/
.lO 12 109 .12 .12 .12 14 :I6
$60 8. 50.
I;
.25 .20 .15 10 :40 .35 30 .70
+60 +45 +35 +60
-t-60 5. D.S. 6. K.B.
P-R (sec.)
pattern
0
j
V,
1 i
j
I
! &I + 1 Rvs
Ii qR qK qI<
1 2 5 5 7
qI< Rs
KS qR qR (IR
qR
da)day da)da> nlo. *
4 wk. 10 wk. 6 mo.*
RS Rs
qR
I Age at time of ECG
4 4”.* 5 nlo.
28 26 52 26 68
3 yr.* 6 mo. 3 yr.*
1 wk. wk. 1 mo. 2 mo. 3 ,110. 3 mo.
58 46 28 28 52 26 20 62 24
6
2 yr.* 3 yr. 3 yr.
24 18
13 4”. 4 yr.
Swgery
I
/ Surziz~al! I
No
Anatomic type
IXed Died Died 1,ived
IA ZC 1C 1
I>ietl I.ivetl
LC I
I’otts
Lived
1
Potts
I~ivetl
1
NO
Died Died Died Died Lived Lived
1B 2c 2B 1B I 1
Blalock SVC-RPA anastomosis
Lived Lived
1 1
Blalocli
Lived
1
NO h-0 Potts
NO
Potts (6 1110.) AS13 eolargemerit (3 yr.)
NO
Blalock No Potts Potts
*Postoperative
record.
p WAVE. A P wave which exceeded 2.5 mm. in Lead II was found in 14 patients (82 per cent), and it was considered to be peaked in at least one electrocardiogram in every case. Minor notching of this complex was present in 4 cases, with the first peak being taller in each. A diphasic P (plus-minus) was present in Lead V1 in 14 cases. Among the 8 cases in which there were follow-up electrocardiograms for 6 months or longer prior to operation, the P wave increased in size by 1 mm. or more in 6. Initially positive P waves in Lead V1 became diphasic in subsequent records in 2 cases. After palliative operations the P wave decreased in size by 1 mm. or more in 3 of the 7 patients in whom subsequent electrocardiograms were available,
remained the same in 2, and increased in size in 2. In one of the latter patients the atria1 septal defect was later enlarged surgically; after this procedure there was a 4.5-mm. decrease in the height of the PII wave (Fig. 1). P-R INTERVAL AND SEGMENT. The P-R interval was prolonged in 2 of the 17 cases (12 per cent) and measured less than 0.11 second in 4 (24 per cent). The P-Rsegment measured 0.04 second or less in each case with a shortened P-R interval, and in 3 cases with a normal P-R interval. AXIS QRS. Left axis deviation was present in 9 of our cases (53 per cent), and a normal electrical axis in 8; the latter will be discussed in detail subsequently. Right axis deviation was not found in our patients.
Tricuspid atresia: ECG study
Serial electrocardiograms were available over an interval of 8 months or longer in 8 patients. During the period of follow-up, 7 of these patients underwent anastomotic procedures. The electrical axis remained unchanged throughout the period of followup in 6. In one patient a 35-degree shift to the left occurred preoperatively, followed by a 25-degree shift to the right after subclavian-pulmonary artery anastomosis. In children this degree of change in the axis in isolated records is of dubious significance, as illustrated by the other patient, whose electrical axis changed back and forth by as much as 40 degrees prior to operation (from +70 to +30 to +SO degrees in three electrocardiograms taken during a period of 3 months). PRECOKDIAL QRS. In Lead V1, rS coml)lexcs were present in 13 cases (77 per Table II. Anatomic
173
cent). In one patient an rSr’ pattern which was present at 5 months of age changed to the rS type after an aortopulmonary anastomosis 17 months later. An rSR’ or RS pattern was seen in one case each, and KS was present in one patient with malrotation of the heart. In Lead Vs, qR complexes were present in 11 cases (65 per cent), KS in 4, and R in 2. The precordial-voltage criteria for left ventricular hypertrophy which were suggested by Nadas6 to be applicable to children (SV, plus RV5 > = 45 mm.) were fulfilled in 9 patients. The intrinsicoid deflection over the left precordium was delayed beyond 0.04 second in only one of our cases. ST-T CHANGES. An upright T wave over the right precordium was found in 8 of 13 patients in whom electrocardiograms were available before 6 months of age. In only
diagnosis and electrical axis: our series and the literature I
Number
1 Axis
TrPe
__~____ Our
series
Ventricular sepal defect
of cases .__~Liternturet
---~ 1
Present
_.._._ _-I
Total
Absent 1
\Vith no transposition A. Pulmonary atresia
1.
Left NOW?
U.
C.
2.
Pulmonary hypoplasia, subpulmonary stenosis
Ko
pulmonary
hypoplasia
Right Left Sane Right Left None
B.
Pulmonary stenosis
or subpulmonary
Left None Right
C.
Large
Left N011e
Right
3IO.2L.22
12 (Cl 1
24* 1 (small)
9* 1 (absent septum)
4 4 2 2 2
6 4 2 28 3 0
2
12 1
1
1 2
1 CD) 41.21.31 3”,9.20
s
73
5 0 0 8 6 3 81
*Other
t.i=
cases not indicated by authors. 1. 7. 11, 13. 19. B = References 7, 19. 21. 36, 37.
2’3.21 26 (B)
2
2 1 0
Left None Right
Totals
j1.23,?8
0
atresia
artery
2
6 (.XL\)
Right With transposition A. Pulmonary
pulmonary
1
References
References
7. 18. 19. 21. 3r). 31, 32. C =
References
7, 12, 13, 17. 18, 21, 24. 33, 34, 3,s. D zz
174
Somlyo and Halloran
4 of these was associated fattening OI inversion of the T wave present in Leads I, ~VL, or Ve. Fifteen patients had electrocardiograms recorded while they were not receiving digitalis; in 11 of these, depression of the S-T segment and/or flattening or inversion of the T wave were present in Leads 1, aVI,, V5, and Vg. In one patient with vertical electrical position of the heart these changes appeared in Leads II, II I, and ~VF. After shunt procedures the ‘I wave became upright in Leads VS or 1’6 in 4 of the 6 patients who were not receiving digitalis (Fig. 2).
2. Factors ageding the presence oj normal and right ask deviation: our series and thr literature. A total of 81 autopsied cases, including 73 collected from the literature, was analyzed to determine the anatomic features which affect axis deviation (Tables I and II). Left axis deviation was present in 61, normal axis in 15, and mild right axis deviation in 5. No documented case of right axis deviation of more than +llO degrees was encountered. Eight of our cases in which the diagnosis was made b>angiocardiography were also included in part of the study dealing with the effects of age on axis deviation (Table III ). EFFECT OF AGE (TABLE III). Right axis deviation or a normal axis was not limited to the patients in early infancy. The average age of these patients was 8 months (range of 1 day to 5; 5 years), and 13 of them were over 3 months old. In serial tracings, a normal axis did not shift to the left with increasing age. Conversely, a left axis was observed frequently in the first month of life, in one case as early as 24 hours of age. ANATOMIC
SCNGROLIPS
(TABLE
II).
‘I‘he
majority of cases in which there was a normal axis were among those associated with pulmonic atresia (Type L4j or transposition of the great vessels with large pulmonary artery (Type 2C) (Fig. 3). Cases of mild right axis deviation were present in either of these subgroups and in none of the others. Three instances of normal axis were present in the cases of common type of tricuspid atresia, that associated with a normal origin of the great vessels, subpulmonic stenosis, and a hypoplastic pulmonary artery (Type 1R). The presence of an in-
tact ventricular septum in 2 of these 3 may be significant, since in 24 of the 26 cases in this group which displayed left axis deviation a ventricular septal defect was present. 1)ISTRIRVTION
OF
AXIS
IN
TYPES
IA
.\NI)
2c (TABLE II). Twenty-nine cases in these subgroups were studied. ANormal or right axis deviation was present in 15 (52 per cent); 10 showed no axis deviation, and in 5 there was right axis deviation. Discussion The characteristic electrocardiographic findings in tricuspid atresia (Fig. 4) have been described by previous authorsS”‘” The most common abnormality of the I’ wave is the presence of a tall, peaked Prr, indicative of right atria1 enlargement. Minor notching of this complex and, more frequentll-, biphnsic plus-minus type of I’ waves over the right precordium provide evidence of additional left atria1 enlargement. Prolongation of the P-K interval was observed by Donzelot and co-workers” in 14 per cent of their cases and was present in 2 of our cases (12 per cent). (:omplete atrioven tricular block was present in one reported cast‘.!’ Conversely, Keith, Rowe and \%d5 commented upon the absence of the P-R segment in 50 per cent of their patients, but did not include measurements of the P-Ji interval. This interval measured 0.11 second or less in duration in 24 per cent of our patients and was associated with QRS complexes of normal duration. A P-R segment of 0.04 second or less was present in all of our patients with shortened P-R intervals, and in 3 lvith normal P-R intervals. The QRS morphology in precordial leads usually reveals evidence of left ventricular predominance, manifested by predominantly negative complexes over the right precordium and positive complexes over the left. Right ventricular predominance is exceptional, but in one illustrated case an Rs complex was present in Lead V*K.“’ Two other cases were described as showing right ventricular enlargement.“~‘” Right bundle branch block was present in one of our cases, and in one case reported bl Chiche.13 Equiphasic RS complexes in I,ead j,rl are next in frequency to the more common rS pattern seen in this leatl.7,‘,’
Fig. 2. Case 4, J .K. I’recordinl leads. .4, Age mosis. B, Age 7 months, after the anastomosis. right in left precordial leads after operation.
Fig. 3. Case Type 2C.
2, N.M.
Age
2 days.
iiQRS
+45
10 days, before The previously
degrees.
Case
aortopulmonary inverted T waves
proved
at autopsy
anastoare up-
to be
Somlyo
176
lbble
III.
Electrical
age: our series
,110. mo. mo. mo. yI-. yr. YI-. yr.
axis
correlated
with
and literature Left axis (number of cases)
Bge
1 day-l l-3 4-6 7-12 l-2 3-5 6-10 11-25
and Halloran
6 15 8 5 11 12 3 6
axis (number
Right
of cases) 1 1 1
Normal axis (xumber of cases) 5 2 6 3 2 1
Electrocardiographic evidence of left ventricular hypertrophy in precordial leads was said to be present in every case studied by Keith, Rowe and Vlad,6 but a similar incidence has not been encountered by others.‘0~18 These discrepancies are presumably due to the questionable accuracy and reliability of the various electrocardiographic criteria of left ventricular hypertrophy in children.r5 In our series the voltage criteria of left ventricular hyper-
trophy which were suggested by Sadas” were fulfilled in only 53 per cent of the cases. Furthermore, in our experience these criteria are not sufficiently stringent to exclude false positives. It is evident, therefore, that the anatomic left ventricular h ypertrophy which is invariably present in cases of tricuspid atresia is not uniforml! reflected in the electrocardiogram. The intrinsicoid deflection may be delayed in left precordial leads.6t7 Left bundle branch block is present in about 5 to 10 per cent of the cases.5,7,8J4 Early electrocardiographic studies of tricuspid atresia emphasized the presence of left axis deviation.1s?,16-18 The frequency of this finding has been confirmed in several large series,7~8~‘sand it is estimated to be present in 80 per cent of the cases.5 However, left axis deviation may be found in patients with cyanotic congenital heart disease other than tricuspid atresia.1u~‘g~2” i’iormal axis is considered to be uncommon, and right axis deviation is extremely rare in well-documented cases of tricuspid atresia; both have been the subject of case reports.Yo-YX Taussig’p? has suggested that
Fig. 4. Case 10, H.P. Age 6 weeks. An example of the most common cardiographic pattern in tricuspid atresia. Tall, peaked P waves, left viation, and left ventricular preponderance are present.
electroaxis dc-
Tricuspid
:I balanced electrical axis may be present “very young infants” with tricuspid atresia. The present study indicates, however, that the age of the patient is not a determining factor of the electrical axis in this anomaly. The anatomic significance of normal and right axis deviation in cases of tricuspid atresia has been analyzed previously by Keith, Rowe and Vlad.5 O& findings- confirm the opinion of these authors that no axis deviation is more likely to be present in cases of tricuspid atresia associated with pulmonic atresia (Type 1A) or with transposition of the great vessels with large pulmonary artery (Type 2C). Mild right axis deviation may also be present in either of these groups and is not limited to those cases of Type 2C13r”4 as previously suggested.5 A more important finding of the present study is that, in these two anatomic subgroups, normal or mild right axis deviation is as common as left axis deviation. In rare instances a normal axis but not right axis deviation may be present in cases of other anatomic variants of tricuspid atresia. Although the number of observations is limited, our data suggest that in the most common variety of tricuspid atresia, that associated with subpulmonic stenosis and normal origin of the great vessels (Type IB), the presence of an intact ventricular septum may predispose to a normal axis. Conversely, a ventricular septal defect was present in 24 of the 26 Type 1B patients with left axis deviation. It has been suggested recently that the presence of normal axis in clinically suspected cases of tricuspid atresia may indicate tricuspid stenosis rather than atresia.25 Congenital tricuspid stenosis is, however, frequently complicated by pullnonic atresia and an intact ventricular septum.*3 Since these associated lesions were found to be present in cases of tric.uspid atresia which showed a normal axis or mild right axis deviation, it appears that these lesions may influence the direction of the electrical axis. The occurrence of left axis deviation in tricuspid atresia is generally accepted to be the result of an increased left ventricular muscle mass.26 The theoretical aspects of in
atresia: ECG study
177
the determinants of axis deviation are beyond the scope of this presentation, although the presence of increased right ventricular muscle thickness, with a rudimentary right ventricular cavity, in cases in which there is no axis deviation lends support to this explanation.10s2Z-?4 The association of tall P waves with small atria1 septal defects in tricuspid atresia had been observed by Taussig,” but this correlation is neither quantitative nor sufficiently consistent to be diagnostic in individual cases6F7We are limited by the small number of patients studied before and after palliative operations. In spite of this reservation we find it of interest that in none of our 5 patients with good surgical results did the P wave become taller postoperatively; in 3 of these it decreased in size, probably as the result of a greater fraction of the cardiac output returning to the left atrium. On the other hand, the P wave continued to increase in height in 2 patients who did not improve after shunt procedures. One of these patients improved after enlargement of her atria1 septal defect, with a concomitant decrease in PII. If these findings can be confirmed in a larger number of patients, an increase in the size of the P wave after shunt procedures in tricuspid atresia may be accepted as an indication for enlargement of the atria1 septal defect, in addition to the clinical criteria suggested by previous authors.27 Summary
Electrocardiographic studies in patients with tricuspid atresia are reported with reference to the significance and frequent), of normal and right axis deviation, the factors which affect axis deviation, and the electrocardiographic changes after palliative operations. The common electrocardiographic pattern of tricuspid atresia is reviewed. Left axis deviation, tall, peaked and occasionally notched PII waves, and left ventricular predominance in precordial leads were found in the majority of cases. The P-R interval is usually normal, but either abnormal prolongation or shortening may be present. The lack of consistent electrocardiographic evidence of left ventricular hypertrophy is contrasted with the ana-
178
Somlyo and Haloran
tomic left ventricular hypertrophy which is invariably present. The majority of cases in which there is a normal axis, and all cases in which there is right axis deviation, are associated with either pulmonic atresia or transposition of the great vessels with large pulmonary artery. These electrical axes are as common as left axis deviation among these two subgroups. The electrical axis shows no significant change with age. n’ormal and mild right axis deviation is not limited to earl). infancy in patients with tricuspid atresia. After successful shunting procedures, the height of the P wave tends to decrease; T waves tend to become upright in left precordial leads. It is suggested that an increase in the size of the P wave after shunt operations should be evaluated as a criterion for enlargement of the atria1 septal defect in these patients. We wish to acknowledge Sidney Blumenthal, Dr. A. Dr. Joseph Grayzel, who criticisms in the preparation
the assistance of Dr. Gregory Jameson, and offered many helpful of this manuscript.
10.
11.
12.
13.
14.
15.
16.
17.
REFERENCES 1.
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9.
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Pearson, H. A., and Cone, T. E., Jr.: Harlequin color change in a young infant with tricuspid atresia, J. Pediat. 50:609, 1957. Miale, J. B., Millard, A. L., Beno, ‘I‘. J., and Custer, G. S.: Congenital tricuspid atresia associated with interauricular and interven tricular septal defects, hr. HEART J. 36:438, 1948. Schaede, A.: Die Tricuspidalatresie, Deutsches Arch. klin. Med. 199:102, 1952. Ohanessian, 0. D., and Rodriquez, M. B.: Congenital tricuspid atresia; report of two cases, A.M.A. Arch. Path. 67:439, 1959. Robinson, A., and Howard, J. E.: Atresia of the tricuspid valve with transposition of the great vessels, Am. J. Dis. Child. 75:57.5, 1948.