Fetal Coarctation

From a manuscript by our group - written by student Sam Amar: "Coarctation of the aorta (CoA) is a form of congenital heart disease that involves the narrowing of the aortic arch lumen, usually at the level of the aortic isthmus. It represents 5 to 8% of congenital heart defects, which means it is a relatively common disease. If unrecognized and untreated in the post-natal setting, this lesion can lead to cardiovascular collapse and organ damage. Therefore, early detection and treatment of CoA is essential for the health of the affected neonates. CoA is challenging to accurately detect in the prenatal setting because of the patency of the ductus arteriosus (DA) and because only 10% of the combined fetal cardiac output passes through the isthmus during fetal life. The DA is a fetal vascular structure that usually connects to the aortic isthmus. The DA obscures the aorta’s anatomy on fetal echocardiography, challenging the direct observation of the aortic arch narrowing during fetal life and of the posterior shelf commonly identified after ductal constriction. As such, fetal cardiology has traditionally relied on indirect prenatal markers such as: 

Because of its limited detection, there is a high false-positive rate for the antenatal suspicion of CoA by fetal echocardiography. As such, numerous newborns who are suspected to have a CoA in the antenatal period will not develop true significant obstruction. The false-positive rate is highest towards the end of pregnancy, when ventricular size discrepancy can be present even in normal fetuses. However, prenatal suspicion still warrants post-natal monitoring and admission to a critical care unit, such as a neonatal intensive care unit (NICU) or a cardiac intensive care unit."

More on post-natal Coarctation here.

Articles on fetal coarctation: here and here.

Further, when facing ventricular asymmetry, one may contemplate a differential diagnosis of various conditions: 

Image provided by Dr Wadi Mawad - Pediatric Cardiology at the Montreal Children's Hospital 

RV to LV dyscrepancy in Apical 4 chamber view in fetal life - increased suspicion for fetal CoA.

Created by Gabriel Altit - Neonatologist / Créé par Gabriel Altit (néonatalogiste) - © NeoCardioLab - 2020-2023 - Contact us / Contactez-nous