Prenatal detection of congenital heart disease--results of a national screening programme.

OBJECTIVE: Congenital heart disease (CHD) is the most common congenital malformation and causes major morbidity and mortality. Prenatal detection improves the neonatal condition before surgery, resulting in less morbidity and mortality. In the Netherlands a national prenatal screening programme was introduced in 2007. This study evaluates the effects of this screening programme. DESIGN: Geographical cohort study. SETTING: Large referral region of three tertiary care centres. POPULATION: Fetuses and infants diagnosed with severe CHD born between 1 January 2002 and 1 January 2012. METHODS: Cases were divided into two groups: before and after the introduction of screening. MAIN OUTCOME MEASURES: Detection rates were calculated. RESULTS: The prenatal detection rate (n = 1912) increased with 23.9% (95% confidence interval [95% CI] 19.5-28.3) from 35.8 to 59.7% after the introduction of screening and of isolated CHD with 21.4% (95% CI 16.0-26.8) from 22.8 to 44.2%. The highest detection rates were found in the hypoplastic left heart syndrome, other univentricular defects and complex defects with atrial isomerism (>93%). Since the introduction of screening, the 'late' referrals (after 24 weeks of gestation) decreased by 24.3% (95% CI 19.3-29.3). CONCLUSIONS: This is the largest cohort study to investigate the prenatal detection rate of severe CHD in an unselected population. A nationally organised screening has resulted in a remarkably high detection rate of CHD (59.7%) compared with earlier literature.

Prenatal detection of transposition of the great arteries reduces mortality and morbidity.

OBJECTIVES: To evaluate the prenatal detection of transposition of the great arteries (TGA), after the introduction of a Dutch screening program in 2007, as well as the effect of prenatal detection on pre- and postsurgical mortality and morbidity. METHODS: In a geographical cohort study, all infants with TGA who were born between 1 January 2002 and 1 January 2012 were included. The cases were divided into two groups: those with and those without a prenatal diagnosis. Pre- and postsurgical mortality was assessed, with a follow-up of 1 year. Presurgical morbidity was assessed in terms of cardiovascular compromise, metabolic acidosis, renal and/or hepatic dysfunction and closure of the duct before initiation of therapy. RESULTS: Of all cases (n = 144), 26.4% were diagnosed prenatally, with detection rates of 15.7% and 41.0% in the first and last 5 years of the study period, respectively. First-year mortality was significantly lower in cases with a prenatal diagnosis of TGA than in those without (0.0% vs 11.4%, respectively). Presurgical mortality (4.9%) only occurred in undetected simple TGA cases. Closure of the duct before treatment, renal dysfunction and hypoxia occurred significantly more often in the group without a prenatal diagnosis. CONCLUSIONS: The prenatal detection rate of TGA has increased significantly since the introduction of the screening program in 2007. Prenatal diagnosis is an important factor that contributes to survival of the infant in the first postnatal year. Furthermore, some morbidity indicators were significantly higher in the group without a prenatal diagnosis. These results justify efforts to improve prenatal screening programs.

Prenatal diagnosis of cardiac defects: accuracy and benefit.

OBJECTIVE: The prenatal diagnosis of cardiac defects can potentially reduce postnatal morbidity and mortality. We wanted to evaluate prenatal cardiac diagnosis accuracy in a population referred for echocardiography. METHODS: Single centre retrospective study of echocardiography referrals between April 1999 and December 2008. We compared the prenatal and postnatal cardiac diagnoses, the modified Aristotle and Wald scores. The final diagnosis Wald score was used to evaluate benefit. RESULTS: Six hundred fetuses were included. Diagnoses included: normal heart (312, 52%); congenital heart defect (CHD) (231, 38.5%); primary arrhythmia (39, 6.5%); or cardiomyopathy, myocarditis or cardiac tumor (18, 3%). The prenatal and postnatal Aristotle and Wald scores correlated in 81% and 86%, respectively, each with significant differences in 22 cases. Four significant CHDs were misdiagnosed, the surgical prediction was incorrect in 7 and 13 false positive diagnoses of aortic coarctation were made. In 76% (455/600) fetuses prenatal diagnosis was considered beneficial. The average CHD Aristotle score was 9.5 ± 5.0. In babies with CHDs and normal karyotype the score was either 6.5 ± 5.0, 12.9 ± 3.1 or 13.2 ± 2.9, in survivors, cases of postnatal demise and cases of pregnancy termination, respectively. CONCLUSION: Prenatal diagnosis was accurate and the counselling appropriate in most cases; however, a few errors were made. The diagnosis of aortic coarctation remains challenging.

Echocardiographic evaluation of fetal cardiac function: clinical and anatomical correlations in two cases of endocardial fibroelastosis.

BACKGROUND: Two fetuses with endocardial fibroelastosis, one with critical aortic stenosis and one with high-output cardiac failure due to chorioangiomatosis, are presented to evaluate the correlation between Doppler echocardiographic findings, the fetal clinical condition and the anatomical substrate found at postmortem. METHODS: Doppler measurements of cardiac function (systolic, diastolic and global) and a cardiovascular score incorporating five parameters of fetal well-being were recorded. RESULTS: In the fetus with critical aortic stenosis, the cardiovascular score was diminished, there was no hydrops, the systolic and global cardiac function indices were within normal limits but the diastolic function indices were abnormal. The fetus with high-output cardiac failure was hydropic, the cardiovascular score was diminished and abnormal Doppler indices of systolic, diastolic and global cardiac function were found. In both fetuses, abnormalities in the measured Doppler parameters were found consistent with clinical cardiac dysfunction and the postmortem findings. CONCLUSION: Recognition of abnormal diastolic function Doppler indices may assist in earlier identification of fetal cardiac compromise.

Nuchal translucency measurement and congenital heart defects: modest association in low-risk pregnancies.

OBJECTIVE: To assess the performance of nuchal translucency (NT) measurement in the first trimester of pregnancy as a marker for congenital heart defects (CHD) in the fetus in a low-risk obstetric population. METHODS: Nuchal translucency screening was offered over a 3-year period to consecutive pregnant women without known a priori risk factors and attending midwife practices in three different areas in the Netherlands. In chromosomally normal fetuses and infants from the study population the NT measurements were matched with CHD detected either prenatally or postnatally. RESULTS: NT screening was offered to 6132 women with an uptake of 83%. A total of 4876 NT measurements was performed. Pregnancy outcome data were available in 4181 cases (86%). Defects of the heart and great arteries (CHD) were diagnosed in 24 cases (prevalence 5.8/1000). Thirteen of these were classified as major (prevalence 3.1/1000). Two major CHD occurred in fetuses showing an increased NT at the first-trimester scan. The sensitivity of NT measurement > 95th and > 99th percentile for all CHD and for major CHD, was 8% and 15%, respectively. The positive likelihood ratios of NT > 95(th) and > 99th percentile for major CHD were 6, 5 and 33, respectively. CONCLUSION: In pregnancies without known risk factors also, an increased NT is associated with major cardiac defects in the fetus and therefore represents an indication for specialized fetal echocardiography. However, this association is too weak to envisage a role for NT measurement as single screening strategy for the prenatal detection of cardiac defects.