PEDIATRIC CARDIOLOGY
Echocardiographic
Diagnosis of Tetralogy of Fallot
The echocardiographic features of tetralogy of Fallot were defined in 25 patients with this malformation proved by cardiac catheterization. The echocardiographic characteristic that was present in all patients and that was most sensitive was the abrupt ending of the interventricular septal echoes with the aorta overriding the ventricular septal defect. The following additional echocardlographic features were frequently demonstrated In these 25 patients: right ventricular enlargement (20 patients), hypertrophy of the interventricular septum (20 patients), diminution of the right ventricular outflow tract (21 patients) and widening of the aorta (24 patients). The suggestion is made that the most specific echocardiographic pattern of tetraiogy of Fallot is the finding of several echocardlographic abnormalltles rather than the single feature of aortic overriding. Recognition of the altered anatomic relation coupled with a complete echocardiographic evaluation of all cardiac structures is a reliable means of diagnosing tetralogy of Fallot.
DOUGLAS C. MORRIS, MD JOEL M. FELNER, MD ROBERT C. SCHLANT, MD, FACC ROBERT H. FRANCH, MD, FACC Atlanta, Georgia
The early use of echocardiography was primarily concerned with the evaluation of acquired heart disease. Improvements in echocardiographic technique and equipment and an enhanced knowledge of echocardiographic anatomic features have led to a wider application of this procedure in recent years. In the field of congenital heart disease, echocardiography was first demonstrated to have diagnostic reliability in patients with an atria1 septal defect.1,2 Subsequently, there have been reports suggesting echocardiographic changes in patients with ventricular septal defect,” single ventricle,3p4 double outlet right ventricle,4 hypoplastic left heart syndrome,4v5 hypoplastic right arteriosus,“,5v6 dextrotransposition of the heart syndrome, 4.5 truncus of Fallot.:3~5,s*g To date, however, the great vessels5,7 and tetralogy sensitivity and the specificity of these findings have not been adequately evaluated in large numbers of patients with each condition. The purpose of this study was to determine whether there is a pattern of echocardiographic features characteristic of tetralogy of Fallot. Methods From the Division of Cardiology, Department of Internal Medicine, Emory University School of Medicine and Grady Memorial Hospital and Emory University Hospital, Atlanta. Georgia. This study was supported in part by National Heart and Lung Institute Training Grants HE05731 and HE5653 from the U. S. Public Health Service, Bethesda, Md. Manuscript accepted March 19, 1975. Address for reprints: Robert C. Schlant. MD, Division of Cardiology, Department of Medicine, 69 Butler Street, S.E., Atlanta, Ga. 30303.
908
December 1975
The Am&can
Echocardiographic evaluation was performed in 25 patients with tetralogy of Fallot proved by cardiac catheterization at either Grady Memorial Hospital or Emory University Hospital. The patients ranged in age from 3 months to 42 years; 10 were female. The majority of the echocardiograms were obtained during the patients’ hospitalization for cardiac catheterization; however, a few patients who had undergone cardiac catheterization prior to this study and who had not been operated on were recalled for echocardiography. Recordings: Echocardiograms were obtained using a Unirad C-100 series diagnostic echoscope system and either a 2.25 megahertz transducer or a 3.5 megahertz transducer with an acoustic lens collimating the sonic beam for a tissue depth of 7.5 cm. The echocardiograms were recorded on either Polaroid photographs of the oscilloscope or on strip chart film. The patients were
Journal of CARDIOLOGY
Volume
30
ECHOCARDlOQRAM IN TETRALOGY OF FALLOT-MORRIS
ET AL.
RVOT
FIGURE 1. Schematic representation of a scanning recording with the transducer beam rotated from a ooint iust distal to the mitral valve cephalad and medial to the aortic valve area. The various measurements made in each patient are indicated by the numbered dimensions. 1 = right ventricular dimension (RV). 2 = left ventricular internal dimension (LVID). 3 = right ventricular outflow tract (RVOT). 4 = aortic root dimension. 5 = left atrium (LA). ALMV = anterior leaflet of mitral valve; IVS = interventricular septum; PLMV = posterior leaflet of mitral valve. (See text.)
Aortic Root
LA
studied in the left lateral decubitus position with the transducer placed along the left sternal border. The transducer was positioned in the interspace that allowed optimal recordings of both leaflets of the mitral valve with the echocardiographic beam directed perpendicularly to the chest wall. This mitral position was used as the pivotal point for all subsequent recordings. From this position the transducer was angulated laterally and slightly inferiorly to obtain the right ventricular, interventricular septal and left ventricular dimensions. A “scanning” M-mode recording was made while the transducer beam was rotated from the mitral position in a slightly medial and cephalad direction to the aortic valve area. The scanning recording was made to determine if the normal relation between contiguous structures was maintained. Finally, with the transducer beam directed in a medial and cephalad direction, a recording was made for measurement of the right ventricular outflow tract and aortic and left atria1dimensions. Measurements: Figure 1 is a schematic representation of an echocardiogram demonstrating the series of measurements made in each patient. The right ventricular dimension was the distance in millimeters from the right ventricular epicardial echo (or, if this was indistinct, from a plane 0.5 cm below the dense chest wall echoes) to the most anterior of the interventricular septal echoes. The left ventricular internal dimension was the distance measured from the most posterior interventricular septal echoes to the endocardial position of the left ventricular wall echoes.] These measurements were made in tracings recorded at a level immediately below the mitral valve leaflets and at the time of the peak R wave of a simultaneously recorded electrocardiogram. The right ventricular outflow tract, which is the relatively echo-free space anterior to the anterior aortic wall, was measured from the dense chest wall echoes to the most anterior echoes from the aortic root. The right ventricular outflow tract, aorta and left atrium were all measured at the level at which the aortic cusps could be visualized. Control subjects: In addition to the 25 patients who constitute the basis of this report, 53 control subjects underwent similar measurements. These were 4 patients with truncus arteriosus, 4 patients with double outlet right ventricle and 45 normal subjects with no clinical or echocardiographic evidence of disease. The normal subjects were classified into the following groups: 10 children aged 2 days to 6 months (average 1 l/2 months) with a body surface area of less than 0.55 m2, 10 children aged 3 to 12 years (average 5 years) with a body surface area of 0.55 to 1.0 m2 and 25 adults aged 18 to 35 years (average 26 years).
Results Tables I and II summarize the data from the 25 patients with tetralogy of Fallot. Table III lists the mean and range of values for our patients along with the normal range for those echocardiographic measurements that are distorted in patients with tetralogy of Fallot. In each of these tables the patients are classified into Groups A, B and C on the basis of body surface area. These particular groupings were used not because there were significant differences in our results among the three groups of patients studied but because previously defined normal dimensions were arranged according to these values for body surface area. The five characteristic echocardiographic features of tetralogy of Fallot were found to be: (1) an increased right ventricular diameter, (2) thickening of the interventricular septum, (3) narrowing of the right ventricular outflow tract, (4) increased aortic root diameter and (5) overriding of the aorta (Fig. 2 and 3). Right ventricular dimension: This dimension was increased in 20 of the 25 patients and the enlargement was much more impressive in adults than in children. To obtain a more accurate reflection of the relative degree of right ventricular enlargement in these patients, we calculated the ratio of right ventricular dimension to the left ventricular internal diameter (Table II). All 25 patients demonstrated a significant increase in this ratio, which has been reported to be approximately 0.33l and was found to be 0.33 or less in each of our normal groups. The thickness of the anterior free wall of the right ventricle could not be satisfactorily recorded in most cases; however, the interventricular septum was abnormally thickened in 20 of the 25 patients. Right ventricular outflow tract: In contrast to the enlargement of the main right ventricular chamber, the width of the right ventricular outflow tract was decreased in 21 of the 25 patients. This decrease was well reflected by the significant reduction in the ratio of the diameter of the right ventricular outflow tract to the left atria1 anteroposterior diameter. Previous dataa had indicated that in adults this
December 1975
The American Journal of CARDIOLOGY
Volume 36
999
ECliDCARDlCGRAM IN TETRALOBY OF FALLOT--MORRIS ET AL.
ratio is normally 1.5 or greater. Our series of normal subjects suggests that this ratio is 1.2 or greater for children with a body surface area of less than 0.55 m2 and 0.9 or greater for children with a body surface area of 0.55 to 1.0 m2. Aortic root diameter: As expected, the aortic root was enlarged in all but 1 of the 25 patients (Case 24, 1 of the 5 adults). In contrast to the right ventricular enlargement, the aortic root enlargement appeared to become less striking with age. Aortic overriding: The most impressive and the most characteristic echocardiographic feature in our cases of tetralogy of Fallot was aortic overriding (last column, Table I). In all 25 patients the interventricular septal echoes ended abruptly rather than blending in a normal fashion without interruption into the anterior aortic wall echoes. Thus, the anterior aortic wall echoes were located abnormally, in a plane anterior to the interventricular septal echoes, with the aorta overriding the echocardiographically defined ventricular septal defect.
FIGURE 2. Schematic representation of cardiac anatomy in tetralogy of Fallot. As the transducer beam is directed along vector 1, echoes from the anterior right ventricular wall, interventricular septum, anterior and posterior leaflets of the mitral valve and posterior left ventricular wall are recorded. When the transducer is then rotated and the beam directed along vector 2. echoes from the anterior and posterior walls of the overriding aortic root and from the posterior left atrial wall are recorded. A0 = aortic root; LA = left atrium; LV = left ventricle: RV = right ventricle.
I
TABLE
Echocsrdiographic Measurements in 25 Patients with Tetralogy of Fallot
Case no.
Age (vr) & Sex
BSA”
RVD (mm)
LVID (mm)
___-
IVS (mm) _____
Aorta (mm)
Aortlc Overriding (mm)
Group A (BSA C0.55m2)
:
3/l 2F 6/l 2F
4 : : Normal range3
2M 2M 3F
7 7 7 7 i
;f:
8 10 21 20 9 15
26
17 15
9
NM 25
NM 14
13-32
3-13
4-6
0.27 0.31 0.51 0.51 0.54 0.51 0.50
22
15
2’: 20 27 28 23
:t: 23 15 16
0.54
Group
9
10 11 12 13 14 15 16 17 18 :z Normal range3
4F 4F 4F 4M 4M 5F !iF
6M 6F 6M 1OF IOM
0.55 0.58 0.60 0.61 0.62 0.57 0.62 0.74 0.76
0.73 0.80 0.82
B (BSA 0.55-l
8
17 21 22 23
7-l
5
0
.Om’) 10
27
; 8 10
:o” 27 30
:: 30 35 30
16 20 16 15 12 21 19 19 30 15
24-42
4--18
5-J
2
27 30 NM 26 z: 32
7
is i 11 10
25 27
z: 30
13 15 20 14 16 10 6 15
17
12 23 11
14-22
0
Group C (BSA >I .O m? ___ 21
22
2JF 30F
1.28 1.50
;;:
207 “2:;
12 14
40t 231
15 23
z:
42M 30M
11.65 .J4
191
25 Normal range’
30M
1.80
1 7.t 35’
15 12 14
23t 22t 25t
25 20 23
7-11
13-22”
0
19-23”
5-12’
* From formula of Dubois and Dubois9a t Per square meter body surface area. BSA = body surface area; IVS = interventricular septum; LVID = left ventricular Internal dimension; structures necessary for the measurement was not seen in the echocardiogram; RVD = right ventricular
910
December 1975
The American Journal of CARDIOLOGY
Volume 36
NM = not measurable dimension.
because one of the
ECHCCARDICGRAM IN TETRALCGY OF FALLOT-MORRIS
ET AL.
RVOT AAW -AAVL -PAW LA 1
I
I
IO mm.
3. Case 22. Echocardiographic arc scan recording. The sweep begins with the transducer beam directed across the right ventricle, interventricular septum and left ventricle at the level of the chordae tendineae of the mitral valve. As the recording is made the transducer is gradually angulated in a cephalad and medial direction, first recording the motion of the mitral valve leaflets, and subsequently echoes from the right ventricular outflow tract, aorta and left atrium. AAVL = anterior aortic valve leaflet; AAW = anterior aortic wall; ARVW = anterior right ventricular wall; Endo = endocardium; Epi =epicardium; IVS = interventricular septum; LA = left atrium; LVID = left ventricular internal dimension; PAW = posterior aortic wall; Peri = pericardium; RV = right ventricle; RVOT = right ventricular outflow tract.
FIGURE
TABLE
TABLE
II
Comparative Echocsrdiographic Data of Patients with Tetralogy of Fallot and Normal Subjects
Echocsrdiographic Ratios and Catheterization Measurements in 25 Patients with Tetralogy of Fallot Echocardiographic Data
III
Group A (BSA l 1 >l
Range Normal lV,“e;&h
Group C (BSA >l .O)
(mm)
RVPI % 0, Sat.
Group B (BSA 0.55-l .O)
range (mm)
Range Normal range RVOTILA Mean Range Normal range Ao$W;ameter (mm) Range Normal range Ao overriding (mm) Mean Range
17.3 14-23 3-l 3
19.2 12-30 4-18
24.0 17-35 4-l 3”
7.5 7-9 4-6
8.3 6-l 1 5-7
13.4 12-15 7-l 1
0.85 0.70-l 1.2+
.o
0.78 0.55-l 0.9+
.o
0.84 0.66-l 21.5&
22.1 17-25 7-15
28.2 25-33 14-22
26.6 22-40 13-22”
13.9 8-12
14.3 6-23
21.2 15-25
.o
*Per square meter body surface area (all other values are absolute). +Personal observations. Ao = aortic; AoR = aortic root; BSA = body surface area (rn’); NS = interventricular septum; RV = right ventricular; RVOT/LA = ratio of diameter of right ventricular outflow tract to left atrial anteroposterior diameter.
NA hy on the basis of a normal right ventricular diameter plus mitral-semilunar valve discontinuity. Although Gramiak et a1.i4 reported that the anterior leaflet of the mitral valve and the posterior aortic root wall were normally at the same depth in the echocardiogram, our study suggests that these structures are not always at exactly the same depth. In 25 patients with no clinical evidence of heart disease and with a normal left ventricular diameter by echocardiogram, the difference in depth of the anterior leaflet of the mitral valve and the posterior aortic root wall at the beginning of ventricular systole ranged from 0 to 8 mm. In 11 patients the depth of these two structures was identical; in 2 patients the depth of the structures varied by 1 mm, in 2 by 2 mm, in 6 by 3 mm, in 2 by 5 mm and in 2 by 8 mm. This finding partly represents an echocardiographic distortion due to the alignment of the transducer beam and the structures in ques-
tion; nevertheless, arc scanning recordings from multiple positions frequently demonstrated these structures to be at slightly different levels. Consequently, we have required a difference of more than 10 mm in levels of the anterior leaflet of the mitral valve and the posterior aortic wall for the definite diagnosis of mitral-semilunar valve discontinuity. In our four cases with mitral-semilunar valve discontinuity and in four of five patients in the study of Chesler et a1.i3 the difference in levels is more than 10 mm. Recently, Chung et al.* indicated that 7 of their 17 patients with tetralogy of Fallot had a difference of 5 to 22 mm in level of anterior leaflet of the mitral valve and the posterior aortic root wall. By our range of normal variation, at least some of their patients would have echocardiographic confirmation of the expected anatomic arrangement. Differentiation from dextrotransposition of the great vessels: The other major form of cyanotic heart disease requiring separation from tetralogy of Fallot is dextrotransposition of the great vessels. The expected distinguishing echocardiographic feature would be the aortic overriding. As others have previously demonstrated echocardiographically, the aorta in cases of dextrotransposition lies immediately below the chest wall echoes and anterior to the pulmonary artery.5y7 In cases of transposition neither of the origins of the great vessels should be astride the interventricular septal echoes.
References 1. Popp RL, Wolfe SB, Hlrata T, et al: Estimation of right and left ventricular size by uitrasound. A study df the echoes from the interventricular septum. Am J Cardiol 24523-530, 1969 2. Diamond A, Dlflon JD, Halne CL, et al: Echocardiographic features of atrial septal defect. Circulation 43: 129-135, 1971 3. Felgenbaum HL: Echocardiography. Philadelphia, Lea & Febiger, 1972 4. Chesfer E. Joffe HS, Beck W, et al: Echocardiography in the dii agnosis of congenital heart disease. Pediat Clin North Am 18: 1163-1190, 1971 5. Godman MJ, Them P, Kldd BSL: Echocardiography in the evaluation of the cyanotic newborn infant. Br Heart J 36:154-166, 1974 6. Chung KJ, drlexson CO, Mannleg JA, et al: Echocardiography in truncus arteriosus: the value of pulmonic vatve detection. Circulation 48:281-286, 1973 7. Dlllon JC, Felgenbaum H, Konecke LL, et al: Echocardiographic manifestations of d-transposition of the great vessels. Am J Cardiol32:74-78. 1973 8. Chung KJ, Nanda NC, Mannlng JA, et al: Echocardiographic
findings in tetralogy of Fallot (abstr). Am J Cardiol 3 1: 126. 1973 9. Tajlk AJ, Gau GT, Ritter DO: Echocardiogram in tetralogy of Fallot. Chest 64:107-108, 1973 9a. Dubok D. Dubols EF: Clinical calorimetry. Arch Intern Med 17: 863-871, 1916 10. Goodman DJ, Harrison DC, Popp RL: Echocardiographic features of primary pulmonary hypertension. Am J Cardiol 33: 438-443, 1974 11. Sawaya J, Longo MR. Schlant RC: Echocardiographic interventricular septal wall motion and thickness: a study in health and disease. Am Heart J 87:681-688, 1974 12. Gramiak R, Shah PM: Cardiac ultrasonography: a review of current applications. Radio1Clin N Am 9:469-490, 1971 13. Chesler E, Joffe HS. Beck W, et al: Echocardiographic recognition of mitral-semilunar valve discontinuity. Circulation 43:725732. 1971 14. Gramlak R, Shah PM, Kramer DH: Ultrasound cardiography: contrast studies in anatomy and function. Radiology 92:939948, 1969
Deoember 1975
The American Journal of CARMOLDGY
Volume 36
913
Echocardiographic
Diagnosis of Tetralogy of Fallot
The echocardiographic features of tetralogy of Fallot were defined in 25 patients with this malformation proved by cardiac catheterization. The echocardiographic characteristic that was present in all patients and that was most sensitive was the abrupt ending of the interventricular septal echoes with the aorta overriding the ventricular septal defect. The following additional echocardlographic features were frequently demonstrated In these 25 patients: right ventricular enlargement (20 patients), hypertrophy of the interventricular septum (20 patients), diminution of the right ventricular outflow tract (21 patients) and widening of the aorta (24 patients). The suggestion is made that the most specific echocardiographic pattern of tetraiogy of Fallot is the finding of several echocardlographic abnormalltles rather than the single feature of aortic overriding. Recognition of the altered anatomic relation coupled with a complete echocardiographic evaluation of all cardiac structures is a reliable means of diagnosing tetralogy of Fallot.
DOUGLAS C. MORRIS, MD JOEL M. FELNER, MD ROBERT C. SCHLANT, MD, FACC ROBERT H. FRANCH, MD, FACC Atlanta, Georgia
The early use of echocardiography was primarily concerned with the evaluation of acquired heart disease. Improvements in echocardiographic technique and equipment and an enhanced knowledge of echocardiographic anatomic features have led to a wider application of this procedure in recent years. In the field of congenital heart disease, echocardiography was first demonstrated to have diagnostic reliability in patients with an atria1 septal defect.1,2 Subsequently, there have been reports suggesting echocardiographic changes in patients with ventricular septal defect,” single ventricle,3p4 double outlet right ventricle,4 hypoplastic left heart syndrome,4v5 hypoplastic right arteriosus,“,5v6 dextrotransposition of the heart syndrome, 4.5 truncus of Fallot.:3~5,s*g To date, however, the great vessels5,7 and tetralogy sensitivity and the specificity of these findings have not been adequately evaluated in large numbers of patients with each condition. The purpose of this study was to determine whether there is a pattern of echocardiographic features characteristic of tetralogy of Fallot. Methods From the Division of Cardiology, Department of Internal Medicine, Emory University School of Medicine and Grady Memorial Hospital and Emory University Hospital, Atlanta. Georgia. This study was supported in part by National Heart and Lung Institute Training Grants HE05731 and HE5653 from the U. S. Public Health Service, Bethesda, Md. Manuscript accepted March 19, 1975. Address for reprints: Robert C. Schlant. MD, Division of Cardiology, Department of Medicine, 69 Butler Street, S.E., Atlanta, Ga. 30303.
908
December 1975
The Am&can
Echocardiographic evaluation was performed in 25 patients with tetralogy of Fallot proved by cardiac catheterization at either Grady Memorial Hospital or Emory University Hospital. The patients ranged in age from 3 months to 42 years; 10 were female. The majority of the echocardiograms were obtained during the patients’ hospitalization for cardiac catheterization; however, a few patients who had undergone cardiac catheterization prior to this study and who had not been operated on were recalled for echocardiography. Recordings: Echocardiograms were obtained using a Unirad C-100 series diagnostic echoscope system and either a 2.25 megahertz transducer or a 3.5 megahertz transducer with an acoustic lens collimating the sonic beam for a tissue depth of 7.5 cm. The echocardiograms were recorded on either Polaroid photographs of the oscilloscope or on strip chart film. The patients were
Journal of CARDIOLOGY
Volume
30
ECHOCARDlOQRAM IN TETRALOGY OF FALLOT-MORRIS
ET AL.
RVOT
FIGURE 1. Schematic representation of a scanning recording with the transducer beam rotated from a ooint iust distal to the mitral valve cephalad and medial to the aortic valve area. The various measurements made in each patient are indicated by the numbered dimensions. 1 = right ventricular dimension (RV). 2 = left ventricular internal dimension (LVID). 3 = right ventricular outflow tract (RVOT). 4 = aortic root dimension. 5 = left atrium (LA). ALMV = anterior leaflet of mitral valve; IVS = interventricular septum; PLMV = posterior leaflet of mitral valve. (See text.)
Aortic Root
LA
studied in the left lateral decubitus position with the transducer placed along the left sternal border. The transducer was positioned in the interspace that allowed optimal recordings of both leaflets of the mitral valve with the echocardiographic beam directed perpendicularly to the chest wall. This mitral position was used as the pivotal point for all subsequent recordings. From this position the transducer was angulated laterally and slightly inferiorly to obtain the right ventricular, interventricular septal and left ventricular dimensions. A “scanning” M-mode recording was made while the transducer beam was rotated from the mitral position in a slightly medial and cephalad direction to the aortic valve area. The scanning recording was made to determine if the normal relation between contiguous structures was maintained. Finally, with the transducer beam directed in a medial and cephalad direction, a recording was made for measurement of the right ventricular outflow tract and aortic and left atria1dimensions. Measurements: Figure 1 is a schematic representation of an echocardiogram demonstrating the series of measurements made in each patient. The right ventricular dimension was the distance in millimeters from the right ventricular epicardial echo (or, if this was indistinct, from a plane 0.5 cm below the dense chest wall echoes) to the most anterior of the interventricular septal echoes. The left ventricular internal dimension was the distance measured from the most posterior interventricular septal echoes to the endocardial position of the left ventricular wall echoes.] These measurements were made in tracings recorded at a level immediately below the mitral valve leaflets and at the time of the peak R wave of a simultaneously recorded electrocardiogram. The right ventricular outflow tract, which is the relatively echo-free space anterior to the anterior aortic wall, was measured from the dense chest wall echoes to the most anterior echoes from the aortic root. The right ventricular outflow tract, aorta and left atrium were all measured at the level at which the aortic cusps could be visualized. Control subjects: In addition to the 25 patients who constitute the basis of this report, 53 control subjects underwent similar measurements. These were 4 patients with truncus arteriosus, 4 patients with double outlet right ventricle and 45 normal subjects with no clinical or echocardiographic evidence of disease. The normal subjects were classified into the following groups: 10 children aged 2 days to 6 months (average 1 l/2 months) with a body surface area of less than 0.55 m2, 10 children aged 3 to 12 years (average 5 years) with a body surface area of 0.55 to 1.0 m2 and 25 adults aged 18 to 35 years (average 26 years).
Results Tables I and II summarize the data from the 25 patients with tetralogy of Fallot. Table III lists the mean and range of values for our patients along with the normal range for those echocardiographic measurements that are distorted in patients with tetralogy of Fallot. In each of these tables the patients are classified into Groups A, B and C on the basis of body surface area. These particular groupings were used not because there were significant differences in our results among the three groups of patients studied but because previously defined normal dimensions were arranged according to these values for body surface area. The five characteristic echocardiographic features of tetralogy of Fallot were found to be: (1) an increased right ventricular diameter, (2) thickening of the interventricular septum, (3) narrowing of the right ventricular outflow tract, (4) increased aortic root diameter and (5) overriding of the aorta (Fig. 2 and 3). Right ventricular dimension: This dimension was increased in 20 of the 25 patients and the enlargement was much more impressive in adults than in children. To obtain a more accurate reflection of the relative degree of right ventricular enlargement in these patients, we calculated the ratio of right ventricular dimension to the left ventricular internal diameter (Table II). All 25 patients demonstrated a significant increase in this ratio, which has been reported to be approximately 0.33l and was found to be 0.33 or less in each of our normal groups. The thickness of the anterior free wall of the right ventricle could not be satisfactorily recorded in most cases; however, the interventricular septum was abnormally thickened in 20 of the 25 patients. Right ventricular outflow tract: In contrast to the enlargement of the main right ventricular chamber, the width of the right ventricular outflow tract was decreased in 21 of the 25 patients. This decrease was well reflected by the significant reduction in the ratio of the diameter of the right ventricular outflow tract to the left atria1 anteroposterior diameter. Previous dataa had indicated that in adults this
December 1975
The American Journal of CARDIOLOGY
Volume 36
999
ECliDCARDlCGRAM IN TETRALOBY OF FALLOT--MORRIS ET AL.
ratio is normally 1.5 or greater. Our series of normal subjects suggests that this ratio is 1.2 or greater for children with a body surface area of less than 0.55 m2 and 0.9 or greater for children with a body surface area of 0.55 to 1.0 m2. Aortic root diameter: As expected, the aortic root was enlarged in all but 1 of the 25 patients (Case 24, 1 of the 5 adults). In contrast to the right ventricular enlargement, the aortic root enlargement appeared to become less striking with age. Aortic overriding: The most impressive and the most characteristic echocardiographic feature in our cases of tetralogy of Fallot was aortic overriding (last column, Table I). In all 25 patients the interventricular septal echoes ended abruptly rather than blending in a normal fashion without interruption into the anterior aortic wall echoes. Thus, the anterior aortic wall echoes were located abnormally, in a plane anterior to the interventricular septal echoes, with the aorta overriding the echocardiographically defined ventricular septal defect.
FIGURE 2. Schematic representation of cardiac anatomy in tetralogy of Fallot. As the transducer beam is directed along vector 1, echoes from the anterior right ventricular wall, interventricular septum, anterior and posterior leaflets of the mitral valve and posterior left ventricular wall are recorded. When the transducer is then rotated and the beam directed along vector 2. echoes from the anterior and posterior walls of the overriding aortic root and from the posterior left atrial wall are recorded. A0 = aortic root; LA = left atrium; LV = left ventricle: RV = right ventricle.
I
TABLE
Echocsrdiographic Measurements in 25 Patients with Tetralogy of Fallot
Case no.
Age (vr) & Sex
BSA”
RVD (mm)
LVID (mm)
___-
IVS (mm) _____
Aorta (mm)
Aortlc Overriding (mm)
Group A (BSA C0.55m2)
:
3/l 2F 6/l 2F
4 : : Normal range3
2M 2M 3F
7 7 7 7 i
;f:
8 10 21 20 9 15
26
17 15
9
NM 25
NM 14
13-32
3-13
4-6
0.27 0.31 0.51 0.51 0.54 0.51 0.50
22
15
2’: 20 27 28 23
:t: 23 15 16
0.54
Group
9
10 11 12 13 14 15 16 17 18 :z Normal range3
4F 4F 4F 4M 4M 5F !iF
6M 6F 6M 1OF IOM
0.55 0.58 0.60 0.61 0.62 0.57 0.62 0.74 0.76
0.73 0.80 0.82
B (BSA 0.55-l
8
17 21 22 23
7-l
5
0
.Om’) 10
27
; 8 10
:o” 27 30
:: 30 35 30
16 20 16 15 12 21 19 19 30 15
24-42
4--18
5-J
2
27 30 NM 26 z: 32
7
is i 11 10
25 27
z: 30
13 15 20 14 16 10 6 15
17
12 23 11
14-22
0
Group C (BSA >I .O m? ___ 21
22
2JF 30F
1.28 1.50
;;:
207 “2:;
12 14
40t 231
15 23
z:
42M 30M
11.65 .J4
191
25 Normal range’
30M
1.80
1 7.t 35’
15 12 14
23t 22t 25t
25 20 23
7-11
13-22”
0
19-23”
5-12’
* From formula of Dubois and Dubois9a t Per square meter body surface area. BSA = body surface area; IVS = interventricular septum; LVID = left ventricular Internal dimension; structures necessary for the measurement was not seen in the echocardiogram; RVD = right ventricular
910
December 1975
The American Journal of CARDIOLOGY
Volume 36
NM = not measurable dimension.
because one of the
ECHCCARDICGRAM IN TETRALCGY OF FALLOT-MORRIS
ET AL.
RVOT AAW -AAVL -PAW LA 1
I
I
IO mm.
3. Case 22. Echocardiographic arc scan recording. The sweep begins with the transducer beam directed across the right ventricle, interventricular septum and left ventricle at the level of the chordae tendineae of the mitral valve. As the recording is made the transducer is gradually angulated in a cephalad and medial direction, first recording the motion of the mitral valve leaflets, and subsequently echoes from the right ventricular outflow tract, aorta and left atrium. AAVL = anterior aortic valve leaflet; AAW = anterior aortic wall; ARVW = anterior right ventricular wall; Endo = endocardium; Epi =epicardium; IVS = interventricular septum; LA = left atrium; LVID = left ventricular internal dimension; PAW = posterior aortic wall; Peri = pericardium; RV = right ventricle; RVOT = right ventricular outflow tract.
FIGURE
TABLE
TABLE
II
Comparative Echocsrdiographic Data of Patients with Tetralogy of Fallot and Normal Subjects
Echocsrdiographic Ratios and Catheterization Measurements in 25 Patients with Tetralogy of Fallot Echocardiographic Data
III
Group A (BSA l 1 >l
Range Normal lV,“e;&h
Group C (BSA >l .O)
(mm)
RVPI % 0, Sat.
Group B (BSA 0.55-l .O)
range (mm)
Range Normal range RVOTILA Mean Range Normal range Ao$W;ameter (mm) Range Normal range Ao overriding (mm) Mean Range
17.3 14-23 3-l 3
19.2 12-30 4-18
24.0 17-35 4-l 3”
7.5 7-9 4-6
8.3 6-l 1 5-7
13.4 12-15 7-l 1
0.85 0.70-l 1.2+
.o
0.78 0.55-l 0.9+
.o
0.84 0.66-l 21.5&
22.1 17-25 7-15
28.2 25-33 14-22
26.6 22-40 13-22”
13.9 8-12
14.3 6-23
21.2 15-25
.o
*Per square meter body surface area (all other values are absolute). +Personal observations. Ao = aortic; AoR = aortic root; BSA = body surface area (rn’); NS = interventricular septum; RV = right ventricular; RVOT/LA = ratio of diameter of right ventricular outflow tract to left atrial anteroposterior diameter.
NA hy on the basis of a normal right ventricular diameter plus mitral-semilunar valve discontinuity. Although Gramiak et a1.i4 reported that the anterior leaflet of the mitral valve and the posterior aortic root wall were normally at the same depth in the echocardiogram, our study suggests that these structures are not always at exactly the same depth. In 25 patients with no clinical evidence of heart disease and with a normal left ventricular diameter by echocardiogram, the difference in depth of the anterior leaflet of the mitral valve and the posterior aortic root wall at the beginning of ventricular systole ranged from 0 to 8 mm. In 11 patients the depth of these two structures was identical; in 2 patients the depth of the structures varied by 1 mm, in 2 by 2 mm, in 6 by 3 mm, in 2 by 5 mm and in 2 by 8 mm. This finding partly represents an echocardiographic distortion due to the alignment of the transducer beam and the structures in ques-
tion; nevertheless, arc scanning recordings from multiple positions frequently demonstrated these structures to be at slightly different levels. Consequently, we have required a difference of more than 10 mm in levels of the anterior leaflet of the mitral valve and the posterior aortic wall for the definite diagnosis of mitral-semilunar valve discontinuity. In our four cases with mitral-semilunar valve discontinuity and in four of five patients in the study of Chesler et a1.i3 the difference in levels is more than 10 mm. Recently, Chung et al.* indicated that 7 of their 17 patients with tetralogy of Fallot had a difference of 5 to 22 mm in level of anterior leaflet of the mitral valve and the posterior aortic root wall. By our range of normal variation, at least some of their patients would have echocardiographic confirmation of the expected anatomic arrangement. Differentiation from dextrotransposition of the great vessels: The other major form of cyanotic heart disease requiring separation from tetralogy of Fallot is dextrotransposition of the great vessels. The expected distinguishing echocardiographic feature would be the aortic overriding. As others have previously demonstrated echocardiographically, the aorta in cases of dextrotransposition lies immediately below the chest wall echoes and anterior to the pulmonary artery.5y7 In cases of transposition neither of the origins of the great vessels should be astride the interventricular septal echoes.
References 1. Popp RL, Wolfe SB, Hlrata T, et al: Estimation of right and left ventricular size by uitrasound. A study df the echoes from the interventricular septum. Am J Cardiol 24523-530, 1969 2. Diamond A, Dlflon JD, Halne CL, et al: Echocardiographic features of atrial septal defect. Circulation 43: 129-135, 1971 3. Felgenbaum HL: Echocardiography. Philadelphia, Lea & Febiger, 1972 4. Chesfer E. Joffe HS, Beck W, et al: Echocardiography in the dii agnosis of congenital heart disease. Pediat Clin North Am 18: 1163-1190, 1971 5. Godman MJ, Them P, Kldd BSL: Echocardiography in the evaluation of the cyanotic newborn infant. Br Heart J 36:154-166, 1974 6. Chung KJ, drlexson CO, Mannleg JA, et al: Echocardiography in truncus arteriosus: the value of pulmonic vatve detection. Circulation 48:281-286, 1973 7. Dlllon JC, Felgenbaum H, Konecke LL, et al: Echocardiographic manifestations of d-transposition of the great vessels. Am J Cardiol32:74-78. 1973 8. Chung KJ, Nanda NC, Mannlng JA, et al: Echocardiographic
findings in tetralogy of Fallot (abstr). Am J Cardiol 3 1: 126. 1973 9. Tajlk AJ, Gau GT, Ritter DO: Echocardiogram in tetralogy of Fallot. Chest 64:107-108, 1973 9a. Dubok D. Dubols EF: Clinical calorimetry. Arch Intern Med 17: 863-871, 1916 10. Goodman DJ, Harrison DC, Popp RL: Echocardiographic features of primary pulmonary hypertension. Am J Cardiol 33: 438-443, 1974 11. Sawaya J, Longo MR. Schlant RC: Echocardiographic interventricular septal wall motion and thickness: a study in health and disease. Am Heart J 87:681-688, 1974 12. Gramiak R, Shah PM: Cardiac ultrasonography: a review of current applications. Radio1Clin N Am 9:469-490, 1971 13. Chesler E, Joffe HS. Beck W, et al: Echocardiographic recognition of mitral-semilunar valve discontinuity. Circulation 43:725732. 1971 14. Gramlak R, Shah PM, Kramer DH: Ultrasound cardiography: contrast studies in anatomy and function. Radiology 92:939948, 1969
Deoember 1975
The American Journal of CARMOLDGY
Volume 36
913
