Mortality and morbidity of major congenital heart disease related to general prenatal screening for malformations.

BACKGROUND: Major congenital heart diseases (CHD) often demand intervention in the neonatal period. Prenatal diagnosis may improve mortality by eliminating the diagnostic delay; however, there is controversy concerning its true effect. We aimed to evaluate the effect of general prenatal screening on prognosis by comparing a period without general prenatal screening to a period with general prenatal screening. METHODS: We conducted a nationwide retrospective study including live born children and terminated fetuses diagnosed with major CHD. Prenatal screening was recommended only in high risk pregnancies between 1996 and 2004, whereas general prenatal screening was recommended between 2005 and 2013. We assessed the influence of general prenatal screening on all-cause mortality, cardiac death, preoperative and postoperative 30-day mortality and complication rate. RESULTS: 1-year mortality decreased over both periods, but the decrease was greater in the screening period (Odds ratio 0.92 (CI 0.83-1.00), p = 0.047). Prenatal detection of major CHD was associated with cardiac death in the period without general screening (Hazard Ratio 2.40 (CI 1.72-3.33), p < 0.001), whereas there was no significant association once general screening was implemented. Similarly, the association between prenatal diagnosis and pre- and postoperative mortality found in the period without general screening was insignificant after the implementation of general screening. CONCLUSION: Mortality in major CHD decreased throughout the study, especially in the period with general prenatal screening. However, comparing a prenatally diagnosed group with a postnatally diagnosed group is vulnerable to selection bias and proper interpretation is difficult.

Live-Born Major Congenital Heart Disease in Denmark: Incidence, Detection Rate, and Termination of Pregnancy Rate From 1996 to 2013.

Importance: The occurrence of major congenital heart disease (CHD) is affected by several variables. Determining the development of the true incidence is critical to the establishment of proper treatment of these patients. Objective: To evaluate time trends in incidence, detection rate, and termination of pregnancy (TOP) rate of major CHD in fetuses in Denmark and assess the influence of the introduction of general prenatal screening in 2004. Design, Setting, and Participants: Nationwide, population-based, retrospective observational study in Denmark from 1996 to 2013 that included a consecutive sample of 14 688 live-born children and terminated fetuses diagnosed as having CHD. Patient records on TOP and children with major CHD were reviewed to validate the diagnoses. Major CHD included univentricular heart, transposition of the great arteries, congenitally corrected transposition of the great arteries, truncus arteriosus, interrupted aortic arch, atrioventricular septal defects, double outlet right ventricle, coarctatio of the aorta, Ebstein anomaly, pulmonary atresia with ventricular septal defect, pulmonary atresia with intact ventricular septum, and tetralogy of Fallot. Data were analyzed between January 2017 and March 2018. Main Outcomes and Measures: Temporal changes in incidence, detection rate, and TOP of major CHD. Results: Of 14 688 children and fetuses diagnosed with CHD, 2695 (18.4%; 95% CI, 17.8-19.1) had major CHD. A total of 7131 boys (1304 with major CHD) and 6926 girls (920 with major CHD) were included, with a median age of 11 years (interquartile range, 6-15 years). During the study period, the live-birth incidence of CHD was constant at 1.22% (95% CI, 1.18-1.26), whereas it decreased for major CHD. When including TOP, the incidence of major CHD did not change over time. The detection rate of major CHD increased from 4.5% (95% CI, 1.2-7.8) to 71.0% (95% CI, 63.3-78.7) (P < .001). At the end of the study, all cases of double outlet right ventricle, Ebstein anomaly, congenitally corrected transposition of the great arteries, and pulmonary atresia with ventricular septal defect were detected prenatally, whereas coarctation of the aorta had the lowest detection rate (21.7%; 95% CI, 3.5-40.0). The TOP rate increased from 0.6% (95% CI, -0.6 to 1.9) to 39.1% (95% CI, 30.9-47.4) (P < .001) among all major CHD. For prenatally diagnosed major CHD, 57.8% of cases were terminated and the proportion did not change significantly throughout the study. Diagnoses leading to TOP included all major CHD diagnoses. Conclusions and Relevance: Detection rates of major CHD improved during the study. This has led to increased TOP rates, with a subsequent 39% decrease in the live-birth incidence of major CHD.