[Prenatal screening for major fetal heart defects by training sonographers in township hospitals and county health centers: a feasibility study].

Objective: To explore the feasibility of screening for major fetal heart disease by training sonographers in township or county level hospitals.

Methods: Training of B ultrasound scan for congenital heart defects was given to the sonographers from one county hospital, and thirteen township hospitals (or the district hospitals), and training of fetal echocardiography was given to sonographers from four city/county hospitals. The trained sonographers who had passed the examinations and had obtained qualifications after six months of independent practice began to screen fetal congenital heart defects. To evaluate the effectiveness, sensitivity and specificity of screening was calculated by using the diagnosis of expert neonatal/fetal echocardiographers as the gold standard.

Results: A total of 3 425 fetuses received one fetal B ultrasound screening, one fetal echocardiography and one neonatal echocardiography from April 1, 2004 to December 31, 2005. One hundred and sixty-five B ultrasound screening images (4.9%) from township hospitals and fifty-six fetal echocardiography images (1.7%) from county or city centers couldn't be reviewed because of poor quality. The sensitivity of fetal B ultrasound screening in the township and county hospitals was 30% and 0, and the specificity 93.3% and 99.9%, respectively. Nine fetuses with a major congenital heart disease were eventually found by the trained sonographers, and two cases were misdiagnosed and two unnoticed. The total sensitivity and specificity of fetal echocardiography were 81.8% and 99.9%, respectively. The sensitivity in the county and city hospitals was 66.7% and 100%, respectively. The specificity in the county and city hospitals was 99.9% and 100%, respectively.

Conclusion: Under the current circumstances, township hospitals are unable to perform effective fetal cardiac screening. Screening on fetal congenital heart disease is suggested to be taken by trained sonographers in county and city level medical centers.