Gynecology
Aortic coarcation
Coarctation of the aorta is a narrowing of the aorta, the most general located at the level of the isthmus (between the departure of the left subclavian artery and the connection with the ductus arteriosus). However, in a number of cases, the narrowed aorta portion may be larger. The prevalence of this anomaly is estimated between 5 and 8% of fetuses with heart disease(1), or 3 to 5 cases/10,000(2). Note a high recurrence rate (2 to 6% if a sibling has been affected, 4% if the mother was the carrier)(1).
Screening
General Characteristics
Fetal position and site will be specified. The axis and heart size are usually normal.
Cavity Study
It is during this first stage that the diagnosis can be mentioned: the left ventricle appears smaller than expected, resulting in a net imbalance of cardiac cavities (figure 1). This difference in size is all the more significant because it is present early in pregnancy. This imbalance is naturally also visible on a small axis cut (Figure 2).
Figure 1. imbalance of the heart chambers (25 SA)
Figure 2. Axial cut
Note that there is a moderate imbalance in the size of cardiac cavities in the third trimester of pregnancy. Finally, in some cases, during the last part of pregnancy, the presence of an anevrysmal Old Valve valve may interfere with the filling of the left ventricle, resulting in an imbalance of the cavities, which may sometimes seem quite important (Figure 3). This purely functional anomaly disappears at birth with the closure of the oval foramen.
Figure 3. Anevrysmal vine (arrows)
Study of large vessels
At the cutting of the 3 vessels and the trachea: the aorta appears to be quite small (figure 4) (in case of doubt, it is possible to refer to large vessel measuring tables(4)). In severe forms, the Doppler allows to show a retrograde flow, linked to vascularization by the arterial channel (Figure 5). Note that it is not uncommon to highlight a fourth vessel (located to the left of the pulmonary artery) on this section, which corresponds to a persistent upper left cellar vein frequently associated with coarctations (Figure 6)(1). In view of this picture, which combines the imbalance of the cavities and the large vessels, attention should be paid to searching for the sign of the "shelf" corresponding to a connection of the narrowed aorta with the arterial canal (Figure 7). Since the small size of the aorta does not allow a full channel connection between these two vessels, a "notch" appears at their junction(5). The volume mode can help to better situate this abnormal connection(6). This sign appears today to be particularly relevant in the diagnosis of coarctations (Figure 8).
Figure 4. Large Vessel Imbalance: the aorta on the right is significantly smaller than normal.
Figure 5. Retrograde vascularization of aorta
Figure 6. Vein cellar upper left. A: dilated coronary sinus (red arrow); B: VCS (blue arrow)
Figure 7. "Shelf": the connection angle is measured here at 111°
Figure 8. "Shelf": Note in B a backward flow (blue arrow)
Severe coarctations can be mentioned as early as the first quarter; they often correspond to severe hypoplasia of the left track (Figures 9 and 10)(7).
Figure 9. Rating to 13 SA.
Figure 10. 15 SA rating.
Balance
The suspicion that aorta is classified requires:
- seek for associated heart defects;
- propose the production of a karyotype and an ACPA;
- finally, as in most cardiac diseases, the ultrasound phist will have to focus on performing a complete review and in particular on finding signs that may suggest a "LOAD" association.
Pronostic
It will be determined by the cardio-pediatrician. These ducto-dependent cardiopathies require adapted care in a center that is broken to this type of pathology.
Heading coordinated by J.-M. Levaillant, Créteil.
References
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1. Abuhamad A, Chaoui R. A practical guide to fetal echocardiography normal and abnormal hearts. Wolters Kluwer 3e ed, 2016. Search the abstract2. Yagel S, Silverman NY, Gembruch U. Fetal cardiology. CRC Press by Taylor& Francis Group, 3e ed, 2019. Search the abstract3. Eisenberg VH, et3. Jowet V et al. Sonographic predic-tors of surgery in fetal coarctaion of the aorta. Ultraso. Three-dimensional transperineal ultrasound for imaging mesh implants following sacrocolpopexy. Ultrasound Obstet Gynecol 2014 ; 43 : 459-65. Search the abstract4. Zalel Y et al. The three vessel and tracheal view of the fetal heart : an in utero sonographic evaluation. Prenat Diagn 2004 ; 24 : 174-8. Search the abstract5. Carvalho JS. OC136: Power Doppler echocardiography makes it possible to visualize the aortic coarctation ‘shelf’ in the fetus. Ultrasound Obstet Gynecol 2007 ; 30, Issue 4 : 409. Search the abstract6. Quarello ER et al. The additional value of 3D ultrasound in fetuses suspected of having coarctation of the aorta. Ultrasound Obstet Gynecol 2008 ; 32 : 406. Search the abstract7. Bronshtein M, Zimmer EZ. Sono-graphic diagnosis of fetal coarctation of the aorta at 14-16 weeks of gesta-tion. Ultrasound Obstet Gynecol 1998 ; 11 : 254-7. Search the abstract8. J.P. Bault, J.M. Levaillant. Échographie Obstétricale Dépistage et diagnostic. Tome 2 : Morphologie normale du fœtus et de ses annexes. Sauramps Éditeurs 2018. Search the abstract
