title: Aberrant right subclavian artery (ARSA) in unselected population at first and second trimester ultrasonography.
abstract: OBJECTIVE
  To evaluate the feasibility of examining aberrant right subclavian artery (ARSA) at first and second trimester gestation, its prevalence and associations in an unselected population.
  
  
  METHODS
  Right subclavian artery (RSA) was prospectively evaluated in 6617 routine patients. When ARSA was detected, fetal echocardiography was offered and fetal karyotyping was discussed. If invasive testing was performed with normal karyotype, fluorescence in situ hybridization for 22q11.2 microdeletion and additionally, in case of nuchal translucency (NT) measurement above the 99(th) centile, oligo array-based comparative genomic hybridization, were offered. In all aneuploidies, NT and first trimester additional ultrasonographic (US) markers assessment (nasal bone, tricuspid valve, ductus venosus) were recorded.
  
  
  RESULTS
  RSA assessment was feasible in 85.3% and 98% of first and second trimester examinations, respectively (overall feasibility 94%). There were detected 89 ARSA (1.42% of the feasible cases), of which 66 in the first trimester. More than 20% were associated to other abnormalities: 10 aneuploidies; 2 microdeletions (15q11.2 and 22q11.2); in the euploid fetuses, 8 associated abnormalities were observed, 4 of which were cardiac defects. In the case of 22q11.2 microdeletion, ARSA was associated only with increased NT.
  
  
  CONCLUSIONS
  Prenatal routine US assessment of the RSA is feasible by highly experienced operators in first trimester screening. There is an important association of ARSA detected in unselected population with fetal abnormalities, including aneuploidies, cardiac defects and genetic anomalies. In trisomy 21 fetuses, ARSA can be the only first trimester US marker or, when associated to increased NT, it can represent the only 'additional' marker.
authors: Fetal Medicine Unit, Di Venere/Sarcone Hospitals, Bari, Italy. rembouskos@hotmail.it
authors: G
authors: G
authors: Rembouskos
authors: U
authors: U
authors: Passamonti
authors: V
authors: V
authors: De Robertis
authors: A
authors: A
authors: Tempesta
authors: G
authors: G
authors: Campobasso
authors: G
authors: G
authors: Volpe
authors: M
authors: M
authors: Gentile
authors: P
authors: P
authors: Volpe
mesh_terms: D000782:Aneuploidy; D000783:Aneurysm / Q000000981:diagnostic imaging* / Q000196:embryology*; D018376:Cardiovascular Abnormalities / Q000000981:diagnostic imaging* / Q000196:embryology*; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics; D000013:Congenital Abnormalities / Q000000981:diagnostic imaging; D003680:Deglutition Disorders / Q000000981:diagnostic imaging* / Q000196:embryology*; D005240:Feasibility Studies; D005260:Female; D005865:Gestational Age; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D011446:Prospective Studies; D013348:Subclavian Artery / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000196:embryology; D016216:Ultrasonography, Prenatal