迷走右锁骨动脉课件文档资料.ppt

aortic arch 主动脉弓主动脉弓brachiocephalic trunk 头臂干头臂干common carotid artery 颈总动脉颈总动脉subclavian 锁骨下的锁骨下的ductus arteriosus 动脉导管动脉导管aberrant 异常的，迷乱的异常的，迷乱的WordsRSA：right subclavian arteryARSA: aberrant right subclavian arteryCorbacioglu Esmer A, Gul A, Nehir A, et al. Detection Rate of Trisomy 21 in Fetuses with Isolated and Non-Isolated Aberrant Right Subclavian Artery.[J]. Fetal Diagnosis & Therapy, 2013, 34(3):140-145. Postnatally, ARSA has been found in about 3% of children and adults with congenital heart defects (CHD) and in 0.1% of the population without cardiac defect. The prevalence of ARSA has been identified by autopsy in 1-2% of normal individuals, whereas it has been found to be more common in cases of Down syndrome, with prevalences ranging from 2.9 to 100%. Chao et al. reported for the first time the identification of ARSA in fetuses with Down syndrome. Since then, other prenatal studies have been carried out, with a divergence of results. Although different research groups demonstrated a higher prevalence of ARSA in Down-syndrome fetuses at present the exact quantification of this phenomenon remains unclear.Objectives To estimate the prevalence of aberrant right subclavian artery (ARSA) in fetuses with Down syndrome. To assess the prevalence of ARSA in euploid fetuses, the feasibility of ultrasound evaluation of the right subclavian artery (RSA) in the first and second trimesters of pregnancy, the performance of ARSA in screeening for trisomy 21 and its association with other abnormalities.Methods A systematic search of the literature from inception until July 2014 was performed in PubMed, EMBASE and MEDLINE to identify relevant articles. The search included the following medical subjects heading terms alone or in different combinations: Down syndrome, trisomy 21, ARSA, aberrant right subclavian artery, ultraound and prenatal diagnosis.Results 1. Prevalence of ARSA Down syndrome fetuses : 23.6%(95%CI,19.4-27.9%) euploids : 1.02%(95%CI,0.86-1.10%) Six studies within the systematic review presented all information required to calculated detection rate(DR) and false-positive rate(FPR) for ARSA in screening for trisomy 21.2. Meta-analysis Analyses of pooled DR and pooled FPR with the six included studies demonstrated respective values of 0.26 and 0.011.  Ultrasound evaluation of the RSA course and origin in the first and second trimesters of pregnancy was feasible in 85% and 98% of cases (first and second trimester, respectively) and it was directly related to sonographic experience and fetal crown-rump lenghth and inversely related to maternal body mass index.3. Feasibility of ARSAChaoui R ,, Rake A ,, Heling K S. Aortic arch with four vessels: aberrant right subclavian artery[J]. Ultrasound in Obstetrics & Gynecology, 2008, 31(1):115-117. In more than 20% of fetuses with ARSA there was an association with other abnormalities but ARSA seemed to be an independent marker of trisomy 21.4. ARSA and associated anomaliesCorbacioglu Esmer A, Gul A, Nehir A, et al. Detection Rate of Trisomy 21 in Fetuses with Isolated and Non-Isolated Aberrant Right Subclavian Artery.[J]. Fetal Diagnosis & Therapy, 2013, 34(3):140-145.ConclusionsARSA appears to be a clinically useful prenatal ultrasound marker of Down syndrome. Addtional testing when ARSA is diagnosed should involve evaluation of all risk factors by applying a mathematical model.ConclusionsThere is insufficient evidence to recommend fetal karyotyping in cases with isolated ARSA.If the background risk is higher or additional markers are present, full fetal karyotyping is advisable, including analysis for 22q11 microdeletion.。