Microarray analysis has no additional value in fetal aberrant right subclavian artery: description of 268 pregnancies and systematic literature review

Abstract

Objectives Fetal aberrant right subclavian artery (ARSA) is a relatively common sonographic finding. Several studies have reported a significant association between ARSA and Down syndrome, as well as 22q11.2 microdeletion. The objective of this study was to assess the risk of abnormal chromosomal microarray analysis (CMA) findings in a large cohort of pregnancies with fetal ARSA as an isolated, as well as a non-isolated, sonographic anomaly. A secondary objective was to review the literature, examining the frequency of chromosomal microarray aberrations in fetuses with isolated ARSA.Methods Data from all pregnancies referred for invasive testing and CMA due to sonographic diagnosis of fetal ARSA, between 2013 and 2017, were obtained retrospectively from the computerized database of the Israeli Ministry of Health. The rate of clinically significant CMA findings in these fetuses was compared to that in a local control population of 2752 low-risk pregnancies with normal ultrasound and serum screening results. In addition, a literature search was conducted in PubMed, from inception to February 2018, of original studies in the English language describing the frequency and nature of microscopic and submicroscopic aberrations in fetuses with isolated ARSA. ResultsOf 246 pregnancies with isolated ARSA that underwent CMA analysis, a clinically significant finding was detected in one (0.4%) pregnancy (trisomy 21). This rate did not differ significantly from that in the control population (P = 0.1574). Of 22 fetuses with non-isolated ARSA, one (4.5%) additional case of trisomy 21 was noted. The frequency of trisomy 21 in this cohort also did not differ from that in the control population (relative risk, 5.5 (95% CI,). The literature search yielded 13 additional relevant papers, encompassing 333 cases of isolated ARSA. Of 579 cases overall (including those of the present study), 13 (2.2%) cases of trisomy 21 were detected, with no cases of 22q11.2 microdeletion. ConclusionWhile an association may exist between non-isolated ARSA and Down syndrome, isolated ARSA might better serve as a soft marker for Down syndrome, rather than a routine indication for invasive prenatal testing.

Chromosomal Microarray Analysis for the Fetuses with Aortic Arch Abnormalities and Normal Karyotype

“…Isolated ARSA is frequently considered to be benign and not associated with T21 or 22q11.2 deletion [18]. Some scholars have even concluded that CMA had no additive value in such cases, but a detailed ultrasound scan should be performed to further evaluate the risk of genetic abnormalities [10,13]. But some scholars suggested that CMA should be considered in cases of prenatally diagnosed fetal cardiovascular malformations, even if the lesion is apparently isolated based on prenatal imaging [39].…”

“…It has been widely accepted for use in fetuses with AAA accompanied with cardiac anomalies or non-cardiac malformations, but its use in the management of cases with an isolated AAA remains controversial. For fetuses with ARSA as an isolated finding, an invasive procedure for CMA testing is not indicated, unless additional ultrasound abnormalities are detected [10,13]. Some authors have recommended karyotyping and FISH for chromosome 22q11.2 microdeletion screening in all fetuses with RAA [3,14].…”

Fetal upper mediastinum — normal and abnormal findings in obstetric ultrasound screening

“…Absent thymus; in aCGH 22q11 deletion confirmation; Ao -aorta; PT -pulmonary trunk; SVC -superior vena cava increasing the risk by 10-fold [32]. However, the last study [33] showed that Down syndrome was present only in 0.4% of cases of isolated ARSA and authors concluded that isolated ARSA should be treated as a soft marker for Down syndrome.…”

Predictive value of aberrant right subclavian artery for fetal Chromosome aneuploidy in women of advanced maternal age

“…Most studies indicated that isolated ARSA had no much clinical signi cance, and there was no need to serve an invasive prenatal chromosomal testing [8][9][10][11][12]. In Italy, an invasive procedure was offered to all patients with intermediate risk and a retrotracheal ARSA [10].…”