Clinical aspects of prenatally detected congenital heart malformations and the yield of chromosomal microarray analysis

Objective: The yield of chromosomal microarray analysis (CMA) for prenatally detected congenital heart defects (CHD) is 6.6% to 19.2%. We evaluated the yield of CMA in cases of prenatally detected CHD in regard to specific clinical characteristics. Methods: Data from 192 cases of CHD including type, clinical and familial background, workup performed during the pregnancy, and pregnancy outcomes were collected. Results: Fetal echocardiography was performed in all cases; 61.4% of CHD were suspected by ultrasound. There was a positive family history (FH) in 15.7%. Abnormal nuchal translucency or umbilical cord anomalies were detected in 1.7% and 5.9%, respectively, and 55.1% were isolated cases. In 11 of 96 cases in which genetic testing was performed, karyotype and CMA were abnormal (11.5%). The detection rate of CMA (performed in 72 cases) was 9.7%. The yield of CMA was similar in simple cases, isolated cases, and cases with a positive FH. CMA was abnormal in 7.3% of ventricular septal defect cases. Conclusion: Most cases of prenatally detected CHD had no additional extra-cardiac, sonographic findings suggesting increased risk for CHD. The yield of CMA testing was significant in all clinical scenarios including simple heart malformations, isolated cases, and cases with a positive FH.