Background: The morphologic analysis of 82 postmortem cases (DHM 1974–1992) demonstrated complete
juxtaposition of the atrial appendages (JAA) in 5 cases (6.1%). Conotruncal anomalies
were associated in all. Left-sided JAA of the right atrial appendage (JRAA) occurred
in three cases, with solitus atria in two, and inversus atria in one. Right-sided
JAA of the left atrial appendage (JLAA) was found in two cases with inversus atria
and solitus atria one each. The anatomical findings of the patient with right JLAA
with solitus atria(s), D-ventricular loop (D), and DORV – Taussig-Bing (S, D, D) are
presented.
Method: We examined the heart specimen with emphasis on the anatomy of the atria and atrial
appendages. The position of the aortic roots, infundibulum, VSD and VSD arterial root
relationship, position/orientation of the infundibular septum, outflow obstruction,
AV valves, ventricles, and additional associated malformations were assessed.
Results: Variations of the classical anatomic characteristics of the DORV–Taussig-Bing or
new anatomical findings in our study patient included subaortic infundibular stenosis
with hypoplastic aortic ostium and interrupted aortic arch (IAA) due to the rightward
and subaortic malalignment of the infundibular septum. Severe overriding and straddling
of the mitral valve through the infundibular septal VSD resulted in stenosis of the
VSD and double inlet RV, hypoplasia of the mitral orifice/LA outlet stenosis, and
small LV. Right-sided complete JLAA was associated. The small LAA was anterior and
adjacent to the right of the aorta, side by side with the enlarged RAA at the right.
The atrial septum secundum was deviated rightward and anteriorly. An atrial septal
defect II was present.
Conclusion: Right-sided complete JLAA with rightward and anteriorly deviated septum secundum
in DORV–Taussig-Bing (S, D, D) has not been described previously to our knowledge.
The associated anatomical findings were essentially opposite of those found in our
three patients with left-sided JRAA, and of the posterior deviation of the septum
secundum reported in 2D echocardiography. The precise diagnosis of the juxtaposed
atrial appendage has important implications before diagnostic or interventional and
surgical procedures that involve the atrial septum such as the Cox-maze procedure
in redo-Fontan patients, BAS, atrial septectomy, or Mustard-Senning procedure.