Download Left juxtaposed atrial appendages: Diagnostic two

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JAM COLL CARDIOL
1983; I(5)'1330.-6
Left Juxtaposed Atrial Appendages: Diagnostic Two-Dimensional
Echocardiographic Features
MARY J. RICE, MD, JAMES B. SEWARD, MD, FACC, DONALD J. HAGLER, MD, FACC,
WILLIAM D. EDWARDS, MD, FACC, PAUL R. JULSRUD, MD, ABDUL J. TAJIK, MD, FACC
Rochester, Minnesota
Left juxtaposition of the atrial appendages is usually
associated with cyanotic congenital heart disease. Recognition of this rare anomaly is important before therapeutic or surgical procedures that involve the atrial
septum can be undertaken (for example, septostomy, the
Mustard or Senning operation and the Fontan anastomosis). The diagnosis of left juxtaposition of the atrial
appendages is most commonly an incidental finding at
the time of surgery or autopsy. This report describes the
two-dimensional echocardiographic visualization of left
juxtaposed atrial appendages. The diagnostic echocardiographic features are based on characteristic alterations of the plane of the atrial septum and visualization of the malpositioned right atrial appendage. On
the basis of these observations, a noninvasive diagnosis
of left juxtaposed atrial appendages is now possible by
means of two-dimensional echocardiography.
Methods
Left juxtaposition of the atrial appendages is a rare congenital malformation usually associated with cyanotic congenital heart disease, in which the right and left atrial appendages lie side by side to the left of the great arteries
(Fig. IA). Recognition of this problem in complex congenital
heart disease is important for complete anticipation of diagnostic or surgical management of these patients. The diagnosis of juxtaposed atrial appendages can only be suspected by certain nonspecific plain film roentgenographic
(1-3) and electrocardiographic (4) findings. To date, angiography has been the only reliable means of preoperative
recognition (3,5-7). However, the diagnosis is more commonly made incidentally at the time of surgery or autopsy
(5,8-18).
In this report, we describe the noninvasive recognition of
left juxtaposition of the atrial appendages by means of twodimensional echocardiography. The diagnostic features are
described and correlated with angiographic, surgical and
autopsy observations. These observations suggest that twodimensional echocardiography allows reliable noninvasive
diagnosis of left juxtaposition of the atrial appendages.
From the Mayo Clinic and Mayo Foundation, Rochester, Minnesota.
Manuscript received August 17, 1982; revised manuscript received December 7, 1982, accepted December 8, 1982.
Address for reprints: Mary 1. Rice, MD, c/o Section of Publications,
Mayo Clinic, 200 First Street S.W , Rochester, Mmnesota 55905.
© 1983 by the American College of Cardiology
Study patients. Ten patients (seven male and three
female), aged 7 months to 17 years, with left juxtaposition
of the atrial appendage are the subjects of this report (Table
1). In four patients, a prospective diagnosis of this condition
was made by two-dimensional echocardiography. Two-dimensional echocardiograms were assessed retrospectively
in the remaining six patients. Five patients were known to
have left juxtaposed atrial appendages on the basis of other
studies (angiography, four patients, and surgery, one patient). In one patient, the echocardiogram was reviewed after
autopsy findings revealed juxtaposed atrial appendages. In
all but one patient, the diagnosis was ultimately confirmed
by surgery (nine patients) or autopsy (two patients), or both.
Echocardiography. Diasonics (Varian) 3000 or 3400
and Advanced Technology Laboratory (ATL) Mark V wide
angle, two-dimensional sector scanners with 2.25, 3 or 5
MHz transducers were utilized. Echocardiographic figures
in this article are 35 mm photographs of stop-action video
images. The standard two-dimensional echocardiographic
scanning techniques utilized have been described (19).
Two scanning planes were the most helpful in elucidating
the anatomic features of left juxtaposition of the atrial appendages. 1) A diagnostic alteration of the plane of the
atrial septum and visualization of the juxtaposed right atrial
appendage were appreciated from the parasternal short-axis
scan at the level of the great arteries (section 9 [19J). 2) A
consistent but nondiagnostic alteration of the posterior atrial
septal configuration was appreciated from the apical four
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LEFT JUXTAPOSED ATRIAL APPENDAGES
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Figure 1. Schematic diagrams illustrating the anatomy and echocardiographic planes of section seen in left juxtapostion of the
atrial appendages. A, Anterior view of the heart showing the right
atrial appendage (RAA) lying posterior and to the left of the transposed great arteries (Ao = aorta; PA = pulmonary artery) and
anterior and superior to the left atrial appendage (LAA). B, The
right atrium and juxtaposed right atrial appendage have been unroofed. Note anteriorly that the floor of the right atrial appendage
is oriented within the heart from right to left in a horizontal plane.
A short-axis plane of section (plane drawn through the atria) demonstrates the abnormal anatomy visualized by a parasternal shortaxis echocardiographic scan. An inset (above) shows the resultant
two-dimensional echocardiographic image. The right atrial appendage lies posterior and to the left of the great arteries and anterior
to the left atrium. The posterior portion of the atrial septum (a) is
oriented normally; the anterior portion (b) is oriented transversely
and parallel to the anterior chest wall. RA = right atrium; RY =
right ventricle. C, Four chamber view of the heart as visualized
by two-dimensional echocardiography. In this plane. the atrial
septum curves toward the right. The left atrium (LA) and right
pulmonary veins (PY) wrap around the posterosuperior aspect of
the right atrium. The inset (above) represents the resultant twodimensional echocardiographic image (that is, four chamber plane).
LY = left ventricle.
chamber view (section 11 [19]) . Other useful planes of
section (19) that were helpful included the subcostal four
chamber plane (section 15) and suprastemallong-axis views
(section 18).
Anteriorly, the atrial septum normally inserts beneath the
posterior wall of a great artery . In normal subjects, this is
the aorta; however, in the presence of transposed great arterie s , it would be the pulmonary artery .
Abnormal spatial orientation of atrial septum. In all 10
patients with left juxtaposed atrial appendages , the major
plane of the anterior atrial septum was abnormal and oriented
horizontally from right to left as visualized from the parasternal short-axis scan at the level of the great arteries (Fig.
2B and 3). The major plane of the anterior portion of the
atrial septum was transverse and parallel to the anterior chest
wall. The horizontal portion of the atrial septum visualized
is the floor of the juxtaposed right atrial appendage (Fig .
IB) . The right atrial appendage was visualized to the patient' s left, posterior to the great arteries and anterior to the
normally positioned left atrium and left atrial appendage
(that is, filling the pericardial transverse sinus). In this projection, the posterior portion of the atrial septum inserted
in a normal manner and separated the lower third of the
right and left atrial cavities . In eight patients, an associated
Results
Two-dimensional echocardiography. The features of
left juxtaposition of the atrial appendages by two-dimensional echocardiography were based on two observations:
I) visualization of the malpositioned right atrial appendage
(Fig . IC); and 2) a characteristic abnormal spatial orientation of the atrial septum(Fig. IB and C) . The parasternal
short-axis scan at or just above the level of the semilunar
valves was the most diagnostic view for visualization of the
malpositioned right atrial appendage. Normally, the right
atrial appendage cannot be visualized and the left and right
atria are separated by an anteroposteriorly (vertical on the
two-dimensional image) oriented atrial septum (Fig. 2A).
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Table 1. Clinical Data in 10 Patients
Case
Age (yr)
& Sex
Diagnosis of Left Juxtaposed Atrial Appendages
Cardiac Diagnosis
Echo
Cath
Surgical Procedure
Autopsy
Prospective Echocardiographic Diagnosis (four patients)
14M
2
IIF
3
9M
4
15M
TA, TGA, PS, Glenn
anastomosis, left SVC,
left BT shunt
DORV, VSD, PA,
hypoplastic TV, Glenn
anastomosis, ASD
Dextrocardia, TGA, VSD,
PS, ASD, right BT
shunt
DORV, VSD, PA, ASD,
nght BT shunt,
Waterston shunt, LAD
off RCA
+
+
Fontan
+
+
Fontan
+
+
Rastelli
+
Repair of DORV
+
Retrospective Echocardiographic Dragnosis (six pattents)
5
7/12M
6
7M
7
17F
8
15M
9
16F
IO
13M
Dextrocardia, TGA, small
VSD,ASD
DORV, PS, VSD,ASD,
straddlmg nght AV
valve, right BT shunt,
right aortic arch
Dextrocardia, TA, ASD,
PS, Glenn anastomosis.
PDA
TA, double-outlet outlet
chamber, PS, left SVC
Postop Rastelli, complete
TGA, obstructed RV to
pulmonary artery
conduit, small residual
VSD
DORV, subaornc VSD,
PA, postop BlalockHanlon + Waterston,
midmuscular VSD,
left SVC
+
+*
Arterial switch
+
+*
Rastelli
+
+*
Fontan
+
+*
Fontan
+
+
Replacement of
RV to
pulmonary
artery conduit
+
+
Repair of
DORV
+
*Prospective angrographic diagnosis ASD = atnal septal defect: AV = atnoventncular. BT = Blalock-Tauvsig. Cath = cardiac cathetenzanon. DORV = double outlet
nght ventricle: Echo = echocardiography. F = female. LAD = left antenor descending coronary artery. M = male. PA = pulmonary atresia. PDA = patent ductus
arteriosus: Postop = postoperative: PS = pulmonary stenosis, RCA = nght coronary artery. RV = nght ventncle. SVC = supenor vena cava. TA = tncuspid atresia. TGA
= transposition of the great arteries: TV = tncuspid valve; VSD = ventncular septal defect. + = performed. - = not performed. - - = nondragnosnc
secundum atrial septal defect was located either in the normally oriented posterior portion of the atrial septum or in
the transition zone from the normal to the horizontal portion
of the atrial septum (Fig, 2B).
A second consistent but nondiagnostic alteration ofatrial
septal orientation was observed in the four chamber plane
as viewed from an apical or subcostal transducer position
(Fig. l C and 4), Superiorly, the atrial septum appeared to
wrap around the posterior aspect of the right atrium (Fig.
4); this made the right atrium appear slightly smaller than
the left. Inferiorly, the atrial septum inserted in a normal
manner at the crest of the ventricular septum. In each patient
with left juxtaposition of the atrial appendages, the atrial
septum had this distinctly abnormal curvature toward the
right as visualized in the four chamber projection, This
alteration of atrial septal anatomy has been seen only in
other complex congenital lesions, especially patients with
isolated dextrocardia, and is not similar to the features seen
with right atrial hypertension (for example, tricuspid regurgitation),
Less commonly from the subcostal or apical four chamber view and with anterior tilt of the transducer, the anteriorly located right atrial appendage could be visualized
coursing beneath the great arteries and leftward over the left
atrial cavity (Fig. 5).
From suprasternal or high parasternal long-axis projections of the great arteries, the juxtaposed right atrial appendage and normally positioned left atrial cavity were both
LEFT JUXTAPOSED ATRIALAPPENDAGES
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1983.(1)5 1330-6
Figure 3. Case 3. Patient with dextrocardia, situs solitus of the
atria and viscera, complete transposition of the great arteries and
leftjuxtapositionofthe atrial appendages. A high parasternalshortaxis scan at the midatrial septum shows the diagnostic orientation
of the atrial septum (AS, small arrows) seen in left juxtaposition
of the atrial appendages. The right atrial appendage (RAA) lies
posterior and to the left of the transposed arteries (Ao = aorta;
PA = pulmonary artery). The body of the left atrium (LA) lies
posterior to the right atrial appendage. Abbreviations as in Figure
I.
Figure 2. Case 4. Patient with double-outlet right ventricle and
left juxtaposedatrial appendages. Sequentialparasternalshort-axis
scans were used. A. At the base of the heart, the two transposed
great arteries are visualized and the atrial septum (AS) is normal
in orientation (that is, oriented anteriorly toward the posterior wall
of the pulmonary artery [PAJ). B, Scanning further superiorly, the
plane of the atrial septum becomes nearly horizontal, coursing
toward the left posterior to the great arteries (refer to inset in Fig.
lB). This distinctly abnormally oriented portion of the atrial septum represents the floor of the juxtaposed right atrial appendage.
The juxtaposed right atrial appendage (RAA) is imaged posterior
and to the left of the great arteries. The left atrium (LA) lies
posterior and to the left. Note that a secundum atrial septal defect
is located just below the floor of the juxtaposed right atrial appendage (arrow). A = anterior; Ao = aorta; AV = aortic valve;
L = left; P = posterior; R = right; RA = right atrium.
imaged posterior to the great arteries (Fig. 6). Normally,
only the left atrium is visible posterior to the great arteries.
This particular observation was obtainable in 4 of the 10
patients.
Angiography and catheterization. In four patients,
sufficient contrast medium in the atria permitted a prospective diagnosis of juxtaposed atrial appendages. In an additional five patients, the diagnosis was made retrospec-
tively, at times with the use of roentgenographic subtraction
techniques. One patient had insufficient contrast medium in
the atria to permit a radiographic diagnosis. In all catheterized patients, simultaneous contrast echocardiography was
performed to help confirm the various anatomic features
described.
Surgery and autopsy. Nine patients underwent surgery
and had sufficient exposure to confirm the diagnosis of left
juxtaposition of the atrial appendages. In the 10th patient
(Case 4), a juxtaposed right atrial appendage was not adequately visualized at surgery but could not be seen in its
usual location. Two of the 10 patients died, and in both the
diagnosis of left juxtaposition of the atrial appendages was
confirmed at autopsy. The right atrium appeared somewhat
smaller than normal but was normally located. The abnormal
plane of the atrial septum, as observed by two-dimensional
echocardiography, was confirmed at autopsy (Fig. 7). Anteriorly, the right atrial appendage was located behind and
to the left of the great arteries and anterior and superior to
the left atrial appendage (Fig. 7A). Posteriorly, the left
atrium partially encircled the superior aspect of the right
atrium (Fig. 7B).
Discussion
Left juxtaposition of the atrial appendages is almost always associated with complex cardiac malformations. Common associations include transposition of the great arteries
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RICE ET AL
Figure 5. Case 10. Subcostal four chamber view with anterior
scanning demonstrating the right atrial appendage (RAA) projecting to the left (arrow) beneath the great arteries. Abbreviations
as before.
Figure 4. Apical four chamber scan in the presence of left juxtaposition of the atrial appendages. A, Case 4 with levocardia.
Notethe unusualrightward angulationof the superioratrial septum
(AS, dashed line and arrow). The left atrium (LA) and right
pulmonary veins (PV) are superior to the right atrium (RA). D,
Case5 with isolated dextrocardiaand left juxtapositionof the atrial
appendages. Note a similar abnormal rightward angulation of the
atrial septum (AS, arrows). I = inferior; mv = mitral valve; S
= superior; tv = tricuspid valve, VS = ventricular septum;
other abbreviations as in Figure I.
(more than 90% of cases), atrial septal defect (78%), ventricular septal defect (65%) and hypoplastic right heart with
outflow obstruction (50%) or inflow obstruction (41%)
(1,2,5,7-13,16,18-25).
Diagnostic and surgical implications. Recognition of
juxtaposed atrial appendages is important for planning certain diagnostic and therapeutic procedures. Because of the
abnormal plane of the atrial septum and position of the atrial
appendages, an altered surgical or diagnostic approach may
be required. Maneuvering a catheter across the abnormally
oriented atrial septum can be difficult because of the more
horizontal orientation of an atrial septal defect or patent
foramen ovale (Fig. 2B). The orifice of the juxtaposed atrial
appendage may be mistaken for an atrial septal defect at the
time of surgery. The leftward position of the right atrial
appendage might also lead to incorrect catheter positioning,
thereby making balloon atrial septostomy a more risky pro-
cedure (1,5,13,16). The usual approach to the surgical Blalock-Hanlon atrial septostomy can be more difficult and risky
because of the smaller right atrial size and rightward position
of the left atrium. However, if juxtaposed atrial appendages
are anticipated, a simple anastomosis of the atrial appendages is often preferred (12,13). Placement of an atrial septal
baffle in the Mustard or Senning operation can be compli-
Figure 6. Case 4. High parasternal long-axis projection in a patient with transposed great arteries. Posteriorly, the juxtaposed
right atrial appendage (white arrow) is visualized posterior to the
transposed main pulmonary artery (MPA) (normally only the left
atrium is visualized). The floor of the juxtaposed right atrial appendage(AS)separates the two atrialcavities. Small black arrows
represent the position of a pulmonary artery band. Abbreviations
as before.
LEl-T JUXTAPOSED ATRIAL APPENDAGES
Figure 7. Case 3. Pathologic specimen cut at two levels in the
four chamber plane in a patient with transposition of the great
arteries and dextrocardia. A, The anterosuperior atrial septum,
forming the floor of the juxtaposed right atrial appendage. sweeps
to the left (ar rows) anterior to the body of the left atrium (LA).
This section corresponds to the echocardiographic anatomy seen
in Figure5. B, Posteroinfenorly, the atrialseptumcurves rightward
(arrows). The left atrium partially encircles the superior aspect of
the right atrium (RA), corresponding to the echocardiographic
anatomy seen in Figure 4. Abbreviations as before.
cated by the smaller right atrium and atypical position of
the orifice of the juxtaposed right atrial appenda ge (12-14).
A Fontan procedure (anastomosis of the right atrium to the
pulmonary artery) can be altered with anastomosis of the
juxtaposed right atrial appendage to the left pulmonary artery (14,17 ).
The diagnosis of left juxtaposition of the atrial app endages is usually an incidental finding at surgery or autopsy.
Only with a high degree of alertness and astute angiographic
observation has prospective diagnosis been made . Chest
roent genography (3) and electrocardiography (4) have been
of little help.
Echocardiographic diagnosis . This report describes the
nonin vasive recognition of left juxtaposition of the atrial
appendages by two-dimensional echo card iography. The observations were based on standard echocard iographic projections (that is, parasternal short-axis view s at the level of
J AM COLL CARDIOL
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the great arterie s and apical or subcostal four chamber views
of the atrial septum) . Recognition of left j uxtaposition of
the atrial appendages was based on characteri stic alterations
of the plane of the atrial septum and visualization of the
leftward positioned right atrial appendage , which cou rses
posterior to the great arteri es. In the four chamber plane ,
the atrial septum curves characteristica lly to the right. Although consistently seen in patients with left juxtaposed
atrial appendages , a similar configuration has been observed
in the presence of other complex lesion s, particularly isolated dextrocardia (situs solitus of the atria and viscer a with
cardia c apex to the right); therefore, in the presence of
dextrocard ia, this particular observation is less specific .
Howe ver , in the presence of levocardia, this observation
should con sistently alert the echocardiographer to the possibilit y of left juxtaposed atrial appendages. This marked
alteration of the posterior septal anatom y has not been seen
in more than 10,000 examinations of lesions other than those
associated with complex congenital heart disease , such as
dextro cardi a, extreme septal malalignment and left j uxtaposition of the atrial appendages.
The most diagnostic echocardiographic observation is
the horizontal orientation of the anterior atrial septum, which
represents the floor of the left juxtaposed right atrial appendage (Fig. IC). The left and right atrial appendages are
both to the left of the great arteries and may be viewed from
multipl e tran sducer position s (parasternal, suprasternal, subcostal and apical ). The right atrial appendage (cavity) is
posterior to the great arteries and courses toward the left
over the left atrium. The floor of the abnormally positioned
atrial appendage accounts for the dia gnostic image. In the
norm al heart , the right atrial appendage is not imaged as it
lies anterior and to the right of the great arteries. The plane
of the anterior atrial septum is normally vertical, with insertion on to the posterior wall of a great artery . The observations described in this report suggest that two-d imensional echocardiography is an excellent noninvasive mean s
for mak ing a definit ive diagnosi s of left juxtaposed atrial
appendages. The sensitivity of this observation awaits further studies .
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