title: Systematic review and meta-analysis of persistent left superior vena cava on prenatal ultrasound: associated anomalies, diagnostic accuracy and postnatal outcome.
abstract: OBJECTIVE
  To quantify the prevalence of chromosomal anomalies in fetuses with persistent left superior vena cava (PLSVC), assess the strength of the association between PLSVC and coarctation of the aorta and ascertain the diagnostic accuracy of antenatal ultrasound in correctly identifying isolated cases of PLSVC.
  
  
  METHODS
  MEDLINE, EMBASE, CINHAL and the Cochrane databases were searched from the year 2000 onwards using combinations of keywords 'left superior vena cava' and 'outcome'. Two authors reviewed all abstracts independently. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale for cohort studies. The rates of the following outcomes were analyzed: chromosomal abnormalities; associated intracardiac anomalies (ICAs) and extracardiac anomalies (ECAs) diagnosed prenatally; additional ICAs and ECAs detected only at postnatal imaging or clinical evaluation but missed at prenatal imaging; and association of PLSVC and coarctation of the aorta. Meta-analyses of proportions were used to combine data.
  
  
  RESULTS
  In total, 2708 articles were identified and 13 (n = 501) were included in the systematic review. Associated ICAs and ECAs were detected at the prenatal ultrasound examination or at a follow-up assessment in 60.7% (95% CI, 44.2-75.9%) and 37.8% (95% CI, 31.0-44.8%) of cases, respectively. Chromosomal anomalies occurred in 12.5% (95% CI, 9.0-16.4%) of cases in the overall population of fetuses with PLSVC and in 7.0% (95% CI, 2.7-13.0%) of isolated cases. Additional ICAs and ECAs were detected only after birth and missed at ultrasound in 2.4% (95% CI, 0.5-5.8%) and 6.7% (95% CI, 2.2-13.2%) of cases, respectively. Coarctation of the aorta was associated with isolated PLSVC in 21.3% (95% CI, 13.6-30.3%) of cases.
  
  
  CONCLUSIONS
  PLSVC is commonly associated with ICAs, ECAs and chromosomal anomalies. Fetuses with isolated PLSVC should be followed up throughout pregnancy in order to rule out coarctation of the aorta. As most of the data in this review were derived from high-risk pregnancies, the rate of associated abnormalities is likely to be higher than that in the general population of fetuses with PLSVC, for which more data are needed. Revisión sistemática y metaanálisis de la persistencia de la vena cava superior izquierda en la ecografía prenatal: anomalías asociadas, precisión del diagnóstico y resultado postnatal RESUMEN OBJETIVOS: Cuantificar la prevalencia de anomalías cromosómicas en fetos con vena cava superior izquierda persistente (VCSIP), evaluar la solidez de la asociación entre la VCSIP y la coartación aórtica, y determinar la precisión del diagnóstico de la ecografía prenatal como método para identificar correctamente casos aislados de VCSIP. MÉTODOS: Se buscó en las bases de datos de MEDLINE, EMBASE, CINHAL y Cochrane artículos publicados desde el año 2000 en adelante, usando combinaciones de las palabras clave "vena cava superior izquierda" y "resultado". Dos de los autores revisaron de forma independiente todos los resúmenes encontrados. La evaluación de calidad de los estudios incluidos se realizó mediante la escala Newcastle-Ottawa para estudios de cohortes. Se analizaron las tasas de los siguientes resultados: anomalías cromosómicas; anomalías intracardíacas (AIC) y anomalías extracardíacas (AEC) asociadas diagnosticadas prenatalmente; AIC y AEC adicionales detectadas sólo en ecografías postnatales o mediante evaluación clínica, pero no observadas en ecografías prenatales; y la asociación entre la VCSIP y la coartación aórtica. Se utilizó un meta-análisis de proporciones para combinar los datos.
  
  
  RESULTS
  En total, se identificaron 2708 artículos y se incluyeron 13 (n = 501) en la revisión sistemática. En la ecografía prenatal o en una revisión de seguimiento se detectaron AIC y AEC asociadas en el 60,7% (IC 95%, 44,2-75,9%) y el 37,8% (IC 95%, 31,0-44,8%) de los casos, respectivamente. Se produjeron anomalías cromosómicas en el 12,5% (IC 95%, 9,0-16,4%) de los casos en la población general de fetos con VCSIP y en el 7,0% (IC 95%, 2,7-13,0%) de casos aislados. Las AIC y AEC adicionales sólo se detectaron después del nacimiento y en el 6,7% (IC 95%, 2,2-13,2%) de los casos, respectivamente. La coartación aórtica se encontró asociada con la VCSIP aislada en un 21,3% (IC 95%, 13,6-30,3%) de los casos.
  
  
  CONCLUSIONS
  La VCSIP está comúnmente asociada a AIC, AEC y anomalías cromosómicas. Los fetos con VCSIP aislada deben ser objeto de seguimiento durante todo el embarazo, con el fin de descartar la coartación aórtica. Como la mayoría de los datos de esta revisión proceden de embarazos de alto riesgo, es probable que la tasa de anomalías asociadas sea más alta que la de la población general de fetos con VCSIP, por lo que se necesitan más datos.
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Gustapane
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Leombroni
authors.affiliation: Fetal Medicine Unit, Division of Developmental Sciences, St George's University of London, London, UK.
authors.forename: A
authors.initials: A
authors.lastname: Khalil
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Giacci
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Marrone
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Bascietto
authors.affiliation: Department of Obstetrics and Gynecology, Università di Roma, Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Rizzo
authors.affiliation: Women's Health and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway.|Department of Obstetrics and Gynaecology, University Hospital of Northern Norway, Tromsø, Norway.
authors.forename: G
authors.initials: G
authors.lastname: Acharya
authors.affiliation: Department of Obstetrics and Gynaecology, SS. Annunziata Hospital, G. D'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Liberati
authors.affiliation: Women's Health and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway.|Department of Obstetrics and Gynaecology, University Hospital of Northern Norway, Tromsø, Norway.
authors.forename: F
authors.initials: F
authors.lastname: D'Antonio
mesh_terms: D001017:Aortic Coarctation / Q000000981:diagnostic imaging* / Q000235:genetics; D002869:Chromosome Aberrations; D015331:Cohort Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal / Q000379:methods*; D054079:Vascular Malformations / Q000000981:diagnostic imaging* / Q000235:genetics; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging*
keywords: congenital heart disease; fetal echocardiography; persistent left superior vena cava; prenatal diagnosis