Wong S F, Ward C, Lee-Tannock A, Le S, Chan F Y
Department of Maternal Fetal Medicine, Mater Mothers' Hospital, South Brisbane, QLD, Australia.
Ultrasound Obstet Gynecol. 2007 Sep;30(3):275-80. doi: 10.1002/uog.4105.
Congenital heart disease is associated with high mortality and morbidity rates, being the most life-threatening defect in the first month of postnatal life and accounting for approximately half of all childhood mortality from birth defects. Despite this, the prenatal detection rate for congenital outflow tract anomalies by ultrasound imaging is relatively low. The aim of this study was to establish a nomogram for the pulmonary artery/aorta (PA/AO) ratio measured in the three-vessel view plane. This ratio was investigated as a simple screening tool for congenital cardiac outflow tract abnormalities.
The study was a prospective evaluation of 966 singleton fetuses at 16-24 weeks of gestation and 46 fetuses with congenital cardiac outflow tract abnormalities. The diameters of the pulmonary artery and aorta were measured in the three-vessel view. The PA/AO ratio was calculated and a nomogram was constructed. The mean and 95% CI for the ratio were defined and the PA/AO ratios of cases with outflow tract abnormalities were plotted against the values for normal fetuses.
The gestational age of the normal group ranged from 16 to 24 weeks, with a median of 19 weeks. The pulmonary artery diameter measured between 2.1 and 4.93 mm (mean, 3.3 mm) and the aorta measured between 2.1 and 5.2 mm (mean, 2.93 mm). The mean (SD) PA/AO ratio was 1.16 (0.18) (95% CI, 0.87-1.58; range 0.61-1.86; median, 1.14). For fetuses with outflow tract abnormalities, the median gestation was 19 weeks and 37/43 (86%) had a PA/AO ratio outside the 95% CI.
The PA/AO ratio derived from measurements in the three-vessel view plane can be used as an initial screening tool for outflow tract anomalies and may have a sensitivity of up to 86%, with a 5% false-positive rate.
先天性心脏病与高死亡率和发病率相关，是出生后第一个月最危及生命的缺陷，约占所有先天性出生缺陷导致儿童死亡的一半。尽管如此，超声成像对先天性流出道异常的产前检出率相对较低。本研究的目的是建立一个在三血管平面测量肺动脉/主动脉（PA/AO）比值的列线图。该比值被作为先天性心脏流出道异常的一种简单筛查工具进行研究。
本研究对966例妊娠16 - 24周的单胎胎儿和46例先天性心脏流出道异常胎儿进行前瞻性评估。在三血管平面测量肺动脉和主动脉直径。计算PA/AO比值并构建列线图。定义该比值的均值和95%置信区间，并将流出道异常病例的PA/AO比值与正常胎儿的值进行对比绘制。
正常组的孕周为16至24周，中位数为19周。肺动脉直径在2.1至4.93毫米之间（均值为3.3毫米），主动脉直径在2.1至5.2毫米之间（均值为2.93毫米）。平均（标准差）PA/AO比值为1.16（0.18）（95%置信区间，0.87 - 1.58；范围0.61 - 1.86；中位数为1.14）。对于流出道异常的胎儿，中位孕周为19周，43例中有37例（86%）的PA/AO比值超出95%置信区间。
在三血管平面测量得到的PA/AO比值可作为流出道异常的初步筛查工具，其敏感性可能高达86%，假阳性率为5%。
