Postnatal impact of a prenatally diagnosed double aortic arch

Abstract

BackgroundA double aortic arch (DAA) is increasingly identified before birth; however, there are no published data describing the postnatal outcome of a large prenatal cohort.ObjectiveTo describe the associations, symptoms and impact of prenatally diagnosed DAA.MethodsRetrospective review of consecutive cases seen at two fetal cardiology units from 2014 to 2019. Clinical records including symptoms and assessment of tracheobronchial compression using flexible bronchoscopy were reviewed. Moderate–severe tracheal compression was defined as >75% occlusion of the lumen.ResultsThere were 50 cases identified prenatally and 48 with postnatal follow-up. Array comparative genomic hybridisation (aCGH) was abnormal in 2/50 (4%), aCGH was normal in 33/50 (66%) and of those reviewed after birth, 13 were phenotypically normal. After birth, there was a complete DAA with patency of both arches in 8/48 (17%) and in 40/48 (83%) there was a segment of the left arch which was a non-patent, ligamentous connection.Stridor was present in 6/48 (13%) on the day of birth. Tracheo-oesophageal compressive symptoms/signs were present in 31/48 (65%) patients at median age of 59 days (IQR 9–182 days). Tracheal/carinal compression was present in 40/45 (88%) cases. Seven of 17 (41%) asymptomatic cases demonstrated moderate–severe tracheal compression. All morphologies of DAA caused symptoms and morphology type was not predictive of significant tracheal compression (p=0.3).ConclusionsGenetic testing should be offered following detection of double aortic arch. Early signs of tracheal compression are common and therefore delivery where onsite neonatal support is available is recommended. Significant tracheal compression may be present even in the absence of symptoms.

Fetal echocardiographic markers to differentiate between a right and double aortic arch

“…The morphology of vascular rings is an important factor in their prognosis 13,17 and the type of vascular ring may also be important in the frequency of genetic associations 4,5 and therefore, it is important to be able to correctly differentiate between the two commonest forms of vascular rings. The postnatal morphology of DAA with atresia of the distal LAA is the commonest form identified 4 and therefore, it is important to utilize prenatal imaging to accurately confirm the diagnosis when all segments of a DAA may be patent. The data presented demonstrates that prenatal differentiation between RAA and DAA cannot simply rely upon the identification of an artery passing anterior and to the left of the trachea as this could be either a (left‐sided) brachiocephalic artery or a LAA 20 .…”

“…The morphology of vascular rings is an important factor in their prognosis 13,17 and the type of vascular ring may also be important in the frequency of genetic associations 4,5 and therefore, it is important to be able to correctly differentiate between the two commonest forms of vascular rings. The postnatal morphology of DAA with atresia of the distal LAA is the commonest form identified 4 and therefore, it is important to utilize prenatal imaging to accurately confirm the diagnosis when all segments of a DAA may be patent.…”

“…It has been shown that children with a DAA tend to present earlier with symptoms/signs of tracheoesophageal compression and are more likely to be associated with residual respiratory post-operative morbidity compared to RAA. 2,[4][5][6][7][8][9][10][11][12][13] with some surgical centres advocating universal early surgery. [13][14][15][16] Accurate prenatal diagnosis of vascular rings assists with perinatal management by facilitating parental education such that possible clinical features can be identified early, leading to timely assessment and treatment.…”

“…[13][14][15][16] Accurate prenatal diagnosis of vascular rings assists with perinatal management by facilitating parental education such that possible clinical features can be identified early, leading to timely assessment and treatment. 4 Prenatal diagnosis has also been shown to be associated with less residual respiratory morbidity after surgical repair particularly in children with a DAA 17,18 and there is interest in early repair to prevent long term morbidity. 13,16 However, differentiation between a RAA-LD and DAA can be challenging with fetal echocardiography especially in the context of a DAA with a smaller left aortic arch (LAA) where the difficulty lies in differentiating this from a left brachiocephalic artery which also passes from right to left in front of the trachea.…”

“…13,16 However, differentiation between a RAA-LD and DAA can be challenging with fetal echocardiography especially in the context of a DAA with a smaller left aortic arch (LAA) where the difficulty lies in differentiating this from a left brachiocephalic artery which also passes from right to left in front of the trachea. 19 This difficulty in differentiation can be perpetuated after birth due to acquired atresia (luminal obliteration) of a segment of the LAA of the DAA, rendering it invisible on postnatal echocardiography and CT. 4,20 Fetal cardiac magnetic resonance imaging can differentiate between RAA and DAA, 20 however this technique is not universally available and fetal echocardiography is the primary diagnostic modality in fetal cardiology units. The first aim of this study is to examine the anatomical findings seen with fetal echocardiography in the setting of a surgically confirmed DAA and secondly, to assess the performance of these anatomical features to correctly identify the diagnosis in a cohort of fetuses with confirmed vascular rings.…”