title: First trimester fetal echocardiography.
abstract: OBJECTIVE
  The aims of this study were to assess the feasibility of performing a complete fetal echocardiographic study during the first trimester of pregnancy, to establish the best week to accomplish a complete evaluation, and to find a relationship between the diameters of the cardiac valves and gestational age.
  
  
  METHODS
  46 fetuses with normal nuchal translucency and venous duct Doppler velocimetry were submitted to echocardiographic studies by the transvaginal approach between the 11 + 0 and 14 + 6 weeks of gestation. A complete echocardiographic evaluation was defined as an examination in which the three basic planes, four-chamber, longitudinal and short-axis views, were obtained.
  
  
  RESULTS
  The rates of complete echocardiography evaluation were 37, 85 and 100% at 11, 12 and 13-14 weeks, respectively. The longitudinal view was the easiest to obtain and the short-axis view was the most difficult one. The diameter of the cardiac valves was compared with the crown-rump length (CRL) and there was no statistically significant difference between either the diameters of the mitral and tricuspid or the aortic and pulmonary valves. A linear growth curve was constructed to demonstrate the diameter correlations.
  
  
  CONCLUSIONS
  The study demonstrated the feasibility of a complete fetal echocardiographic evaluation by the transvaginal approach during the first trimester of gestation. The rate of a complete evaluation increased along the period and reached 100% when the CRL was 64 mm or 13 weeks of gestational age. There was a linear correlation between the cardiac valve diameters and the CRL revealing a relationship between the cardiac and fetal development. The absence of a statistically significant difference between the left and right valve dimensions possibly means that there is no predominance of right or left chambers during this period of evaluation.
authors.affiliation: Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Sandra Regina
authors.initials: SR
authors.lastname: Marques Carvalho
authors.forename: Maria Célia
authors.initials: MC
authors.lastname: Mendes
authors.forename: Omero Benedito
authors.initials: OB
authors.lastname: Poli Neto
authors.forename: Aderson Tadeu
authors.initials: AT
authors.lastname: Berezowski
mesh_terms: D004452:Echocardiography; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D016216:Ultrasonography, Prenatal