title: The association between isolated fetal echogenic cardiac foci on second-trimester ultrasound scan and trisomy 21 in low-risk unselected women.
abstract: OBJECTIVE
  To determine the prevalence of and the association between trisomy 21 and isolated fetal echogenic cardiac foci (FECF) identified in the second trimester in an unselected low-risk population.
  
  
  METHODS
  All cases with isolated FECF were collected by reviewing the antenatal ultrasound database for 3 consecutive years. In order to include all trisomy 21 cases for the same period, the regional cytogenetics database and pediatric databases were examined. A 2 x 2-table analysis was performed to establish the sensitivity, specificity and positive and negative predictive values of isolated FECF as a screening test for trisomy 21 in a low-risk unselected population.
  
  
  RESULTS
  In the 3-year period of the study the total number of deliveries was 11,105, of which 10,769 (97%) had a routine detailed anomaly scan between 16 and 24 weeks' gestation. There were 311 cases (2.9%) of isolated FECF. Among these there was only one case (0.3%) of trisomy 21. In the same period, the total number of trisomy 21 cases was 14. Accordingly, the sensitivity of isolated FECF for detecting trisomy 21 was 7.1% and the specificity was 97.1%. Positive and negative predictive values of FECF were 0.3% and 99.9%, respectively.
  
  
  CONCLUSIONS
  In an otherwise healthy pregnancy, the finding of isolated FECF on a routine second-trimester anomaly scan is normal and should not be considered as a risk factor for trisomy 21 in an unselected low-risk population.
authors.affiliation: Department of Obstetrics & Gynaecology, Northwick Park & St Mark's NHS Trust, Harrow, Middlesex, UK. pauline.mills@nwlh.nhs.uk
authors.forename: R F
authors.initials: RF
authors.lastname: Lamont
authors.forename: E
authors.initials: E
authors.lastname: Havutcu
authors.forename: S
authors.initials: S
authors.lastname: Salgia
authors.forename: P
authors.initials: P
authors.lastname: Adinkra
authors.forename: R
authors.initials: R
authors.lastname: Nicholl
mesh_terms: D000293:Adolescent; D000328:Adult; D002114:Calcinosis / Q000150:complications / Q000000981:diagnostic imaging*; D004314:Down Syndrome / Q000150:complications / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000379:methods; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007621:Karyotyping; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D018566:Pregnancy, High-Risk; D011296:Prenatal Diagnosis / Q000379:methods; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D016216:Ultrasonography, Prenatal / Q000379:methods*