DeVore G R, Medearis A L, Bear M B, Horenstein J, Platt L D
Genetics Institute Fetal Diagnostic Center, Pasadena, California.
J Ultrasound Med. 1993 Nov;12(11):659-63. doi: 10.7863/jum.1993.12.11.659.
The four-chamber view of the heart is an important component of the ultrasonographic examination of the fetus. However, during the second trimester of pregnancy the fetal heart cannot always be imaged in every patient. The purpose of this study was to ascertain the rate of successful imaging of the fetal heart during the second trimester and to determine factors that may influence imaging.
Seven hundred and nine second trimester fetuses were examined and an attempt was made to obtain the four-chamber and outflow tract views of the heart. Analysis included multiple logistic regression models of the main effects and interactions of ten candidate variables.
The four chambers and outflow tracts were imaged in 643 fetuses (90.7%) and not imaged in 66 (9.3%). Fifty-two of 709 patients (7.3%) had had previous surgery. In the 52 patients with a history of previous surgery, the heart could not be imaged in 18 (34%). Six hundred and fifty-seven patients (92.7%) did not have previous surgery. Of this group, the fetal heart could not be imaged in 48 (7.3%). In only one fetus in which the heart could not be imaged was it because of fetal position. Three independent risk factors that influenced imaging of the fetal heart were gestational age, maternal adipose tissue thickness, and previous lower abdominal surgery. Increasing gestational age increased the probability of imaging the heart, whereas increasing adipose tissue thickness and a history of previous surgery decreased the probability of imaging the heart.
When the fetal heart cannot be imaged during the second trimester, these factors should be identified. Using data from this study, the gestational age at which the highest probability of imaging the heart can be determined if the thickness of the adipose tissue and a history of lower abdominal surgery are known.
心脏四腔心切面是胎儿超声检查的重要组成部分。然而，在妊娠中期，并非每位患者都能成功成像胎儿心脏。本研究的目的是确定妊娠中期胎儿心脏成功成像的比率，并确定可能影响成像的因素。
对709例妊娠中期胎儿进行检查，尝试获取心脏的四腔心和流出道切面图像。分析包括对10个候选变量的主效应和相互作用的多重逻辑回归模型。
643例胎儿（90.7%）成功成像心脏四腔心和流出道，66例（9.3%）未成功成像。709例患者中有52例（7.3%）曾接受过手术。在52例有手术史的患者中，18例（34%）心脏未能成像。657例患者（92.7%）无手术史。在这组患者中，48例（7.3%）胎儿心脏未能成像。在唯一一例心脏未能成像的胎儿中，原因是胎儿体位。影响胎儿心脏成像的三个独立危险因素是孕周、母体脂肪组织厚度和既往下腹部手术史。孕周增加会增加心脏成像的概率，而脂肪组织厚度增加和既往手术史会降低心脏成像的概率。
当妊娠中期无法成像胎儿心脏时，应识别这些因素。利用本研究的数据，如果已知脂肪组织厚度和下腹部手术史，就可以确定心脏成像概率最高时的孕周。
