Keywords:
Congenital, Contrast agent-intravenous, CT-Angiography, CT, Cardiovascular system, Cardiac
Authors:
N. Rokytska1, R. Tammo1, T. Yalynska2, H. Morkovkina1, A. Halchenko3; 1Kyiv/UA, 2Kyiv, Kyiv/UA, 3Kiev/UA
DOI:
10.1594/ecr2018/C-0780
Aims and objectives
Heterotaxy is a class of congenital disorders resulting from failure to establish normal left – right (L – R) asymmetry during embryonic development.
which leads to symmetry of morphologically asymmetric organs.
[1]
The lungs,
liver,
spleen,
stomach,
and atria are usually asymmetric organs and the term situs is used to define the position of the atria and viscera relative to the midline or sagital plane.
Any unusual symmetry of asymmetric thoracic and abdominal organs,
and the atrial appendages within the heart we can call a “situs ambiguous”.
Patients with “situs ambiguous” can be stratified into the subsets of heterotaxy with isomerism of the right atrial appendages (Fig.
1) and heterotaxy with isomerism of the left atrial appendages (Fig.
2).
[2]
Historically,
heterotaxy has been determined on the basis of splenic anatomy with patients being classified has having asplenia or polysplenia.
This approach is not ideal,
and it is now recognized that heterotaxy is better determined on the basis of isomerism of the atrial appendages rather than other features such as splenic anatomy as it is the atrial appendage morphology that is the most constant feature.
[3]
ANATOMY OF RIGHT ATRIUM (Fig.
3,
4)
- • Limb of fossa ovalis
- • Large pyramidal appendage
- • Crista terminalis
- • Pectinate muscles
- • Receives systemic veins (SVC,
IVC)
ANATOMY OF LEFT ATRIUM (Fig.
5)
- • Ostium secundum
- • Small fingerlike appendage
- • Crista terminalis is abcent
- • Pectinate muscles is abcent
- • Receives pulmonary veins
Heterotaxy syndrome with right isomerism:
- • Bilateral trilobed lungs with long eparterial bronchi
- • Bilateral right atria
- • Liver is symmetrical and centrally located
- • Stomach is in indeterminate position
- • Generally asplenia