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

The yield of SNP microarray analysis for fetal ultrasound cardiac abnormalities

BACKGROUND

Chromosomal microarray analysis (CMA) has emerged as a critical instrument in prenatal diagnostic procedures, notably in assessing congenital heart diseases (CHD). Nonetheless, current research focuses solely on CHD, overlooking the necessity for thorough comparative investigations encompassing fetuses with varied structural abnormalities or those without apparent structural anomalies.

OBJECTIVE

This study sought to assess the relation of single nucleotide polymorphism-based chromosomal microarray analysis (SNP-based CMA) in identifying the underlying causes of fetal cardiac ultrasound abnormalities.

METHODS

A total of 2092 pregnant women who underwent prenatal diagnosis from 2017 to 2022 were included in the study and divided into four groups based on the presence of ultrasound structural abnormalities and the specific type of abnormality. The results of the SNP-Array test conducted on amniotic fluid samples from these groups were analyzed.

RESULTS

Findings from the study revealed that the non-isolated CHD group exhibited the highest incidence of aneuploidy, overall chromosomal abnormalities, and trisomy 18, demonstrating statistically significant differences from the other groups (p < 0.001). Regarding the distribution frequency of copy number variation (CNV) segment size, no statistically significant distinctions were observed between the isolated CHD group and the non-isolated CHD group (p > 0.05). The occurrence rates of 22q11.2 and 15q11.2 were also not statistically different between the isolated CHD group and the non-isolated congenital heart defect group (p > 0.05).

CONCLUSION

SNP-based CMA enhances the capacity to detect abnormal CNVs in CHD fetuses, offering valuable insights for diagnosing chromosomal etiology and facilitating genetic counseling. This research contributes to the broader understanding of the utility of SNP-based CMA in the context of fetal cardiac ultrasound abnormalities.

Chromosomal abnormalities in fetuses with congenital heart disease: a meta-analysis

PURPOSE

The aim of this meta-analysis was to evaluate the risk of chromosomal abnormalities in fetuses with congenital heart disease (CHD).

METHODS

Four literature databases were searched until 17th January 2022 using the relevant medical subject heading terms, word variants, and keywords for "congenital heart defect, fetal, and chromosomal abnormalities". The prevalence of overall chromosomal abnormality, aneuploidy, 22q11 deletion, other copy number variants (CNVs), and variants of unknown significance (VOUS) was analyzed.

RESULTS

45 studies met the inclusion criteria for the analysis. The pooled proportion of overall chromosomal abnormalities, aneuploidy, 22q11 deletion, and other CNVs in fetuses with CHD was 23% (95% CI: 20-26%), 19% (95% CI, 16-22%), 2% (95% CI, 2-3%), and 4% (95% CI, 3-5%), respectively. The incidence of overall chromosomal abnormalities, aneuploidy, and other CNVs in non-isolated CHD was higher than in isolated CHD, with odds ratios of 3.08, 3.45, and 4.02, respectively. The incidence of overall chromosomal abnormalities in septal defects was higher than in conotruncal defects and other defects, with odds ratios of 1.60 and 3.61, respectively. In addition, the pooled proportion of VOUS in CHD was 4%.

CONCLUSION

CHD is commonly associated with chromosomal abnormalities. If karyotyping or fluorescence in situ hybridization is normal, chromosomal microarray should be performed to look for submicroscopic abnormalities, especially in fetuses with non-isolated CHD and septal defects.

Chromosomal Microarray Analysis in Fetuses Detected with Isolated Cardiovascular Malformation: A Multicenter Study, Systematic Review of the Literature and Meta-Analysis

Cardiovascular malformations (CVM) represent the most common structural anomalies, occurring in 0.7% of live births. The CVM prenatal suspicion should prompt an accurate investigation with fetal echocardiography and the assessment through genetic counseling and testing. In particular, chromosomal microarray analysis (CMA) allows the identification of copy number variations. We performed a systematic review and meta-analysis of the literature, studying the incremental diagnostic yield of CMA in fetal isolated CVM, scoring yields for each category of heart disease, with the aim of guiding genetic counseling and prenatal management. At the same time, we report 59 fetuses with isolated CVM with normal karyotype who underwent CMA. The incremental CMA diagnostic yield in fetuses with isolated CVM was 5.79% (CI 5.54–6.04), with conotruncal malformations showing the higher detection rate (15.93%). The yields for ventricular septal defects and aberrant right subclavian artery were the lowest (2.64% and 0.66%). Other CVM ranged from 4.42% to 6.67%. In the retrospective cohort, the diagnostic yield was consistent with literature data, with an overall CMA diagnostic yield of 3.38%. CMA in the prenatal setting was confirmed as a valuable tool for investigating the causes of fetal cardiovascular malformations.

Prenatal diagnosis for fetuses with isolated and non-isolated congenital heart defects using chromosomal microarray and exome sequencing

OBJECTIVE

To investigate the use of chromosomal microarray (CMA) and Exome sequencing (ES) in fetuses with congenital heart disease (CHD). &#13; METHODS: The Fetal Medicine Unit of Shanghai First Maternity and Infant Hospital records were reviewed to ascertain all cases diagnosed with CHD by level 2 ultrasound examination between 2016 and 2019. Cases were categorized as isolated or associated with other abnormalities or fetal growth restriction. CMA was offered to all cases as a first-line genetic test followed by ES when CMA was non-diagnostic.&#13; RESULTS: Of the 586 ascertained, 84 (14.3%) had causative CMA abnormality, of which 8.8% (35/400) were in fetuses with isolated CHD and 26.3% (49/186) in those with other abnormalities. ES was performed in 47 cases with a negative CMA. Causative variants were identified in two (10.5%, 2/19) isolated cases and four(14.3%, 4/28) with other abnormalities.&#13; CONCLUSION: Invasive procedures with CMA should be offered in pregnancies complicated by both non-isolated and isolated cardiac abnormalities. When CMA is not diagnostic, ES can add diagnostic value in both groups and should be considered even for fetuses with an isolated CHD This article is protected by copyright. All rights reserved.

Molecular Approaches in Fetal Malformations, Dynamic Anomalies and Soft Markers: Diagnostic Rates and Challenges-Systematic Review of the Literature and Meta-Analysis

Fetal malformations occur in 2-3% of pregnancies. They require invasive procedures for cytogenetics and molecular testing. "Structural anomalies" include non-transient anatomic alterations. "Soft markers" are often transient minor ultrasound findings. Anomalies not fitting these definitions are categorized as "dynamic". This meta-analysis aims to evaluate the diagnostic yield and the rates of variants of uncertain significance (VUSs) in fetuses undergoing molecular testing (chromosomal microarray (CMA), exome sequencing (ES), genome sequencing (WGS)) due to ultrasound findings. The CMA diagnostic yield was 2.15% in single soft markers (vs. 0.79% baseline risk), 3.44% in multiple soft markers, 3.66% in single structural anomalies and 8.57% in multiple structural anomalies. Rates for specific subcategories vary significantly. ES showed a diagnostic rate of 19.47%, reaching 27.47% in multiple structural anomalies. WGS data did not allow meta-analysis. In fetal structural anomalies, CMA is a first-tier test, but should be integrated with karyotype and parental segregations. In this class of fetuses, ES presents a very high incremental yield, with a significant VUSs burden, so we encourage its use in selected cases. Soft markers present heterogeneous CMA results from each other, some of them with risks comparable to structural anomalies, and would benefit from molecular analysis. The diagnostic rate of multiple soft markers poses a solid indication to CMA.

Prenatal and postnatal chromosomal microarray analysis in 885 cases of various congenital heart defects

PURPOSE

This study aimed to evaluate the prevalence of clinically significant (pathogenic and likely pathogenic) variants detected by chromosomal microarray (CMA) tests performed for prenatally and postnatally detected congenital heart defects.

METHODS

A retrospective evaluation of CMA analyses over a period of four years in a single tertiary medical center was performed. Detection rate of clinically significant variants was calculated in the whole cohort, prenatal vs. postnatal cases, and isolated vs. non-isolated CHD. This rate was compared to previously published control cohorts, and to a theoretical detection rate of noninvasive prenatal testing (NIPS; 5 chromosomes).

RESULTS

Of the 885 cases of CHD, 111 (12.5%) clinically significant variants were detected, with no significant difference between the 498 prenatal and the 387 postnatal cases (10.8% vs. 14.7%, p = 0.08). In both groups, the detection rate was significantly higher for non-isolated vs. isolated CHD (76/339 = 22.4% vs. 35/546 = 6.4%, respectively, p < 0.05). The detection rate was higher than the background risk in both groups, including cases of postnatal isolated CHD. 44% of abnormal findings in the prenatal setting would be detectable by NIPS.

CONCLUSION

CMA should be performed for both prenatally and postnatally detected CHD, including postnatal cases of isolated CHD, while NIPS can be considered in specific scenarios.

Estimating the frequency of causal genetic variants in foetuses with congenital heart defects: a Chinese cohort study

BACKGROUND

The belief that genetics plays a major role in the pathogenesis of congenital heart defects (CHD) has grown popular among clinicians. Although some studies have focused on the genetic testing of foetuses with CHD in China, the genotype-phenotype relationship has not yet been fully established, and hotspot copy number variations (CNVs) related to CHD in the Chinese population are still unclear. This cohort study aimed to assess the prevalence of chromosomal abnormalities in Chinese foetuses with different types of CHD.

RESULTS

In a cohort of 200 foetuses, chromosomal abnormalities were detected in 49 (24.5%) after a prenatal chromosome microarray analysis (CMA), including 23 foetuses (11.5%) with aneuploidies and 26 (13.0%) with clinically significant CNVs. The additional diagnostic yield following whole exome sequencing (WES) was 11.5% (6/52). The incidence of total chromosomal abnormality in the non-isolated CHD group (31.8%) was higher than that in the isolated CHD group (20.9%), mainly because the incidence of aneuploidy was significantly increased when CHD was combined with extracardiac structural abnormalities or soft markers. The chromosomal abnormality rate of the complex CHD group was higher than that of the simple CHD group; however, the difference was not statistically significant (31.8% vs. 23.6%, P = 0.398). The most common CNV detected in CHD foetuses was the 22q11.2 deletion, followed by deletions of 5p15.33p15.31, deletions of 15q13.2q13.3, deletions of 11q24.2q25, deletions of 17p13.3p13.2, and duplications of 17q12.

CONCLUSIONS

CMA is the recommended initial examination for cases of CHD in prenatal settings, for both simple heart defects and isolated heart defects. For cases with negative CMA results, the follow-up application of WES will offer a considerable proportion of additional detection of clinical significance.

Comprehensive evaluation of genetic variants using chromosomal microarray analysis and exome sequencing in fetuses with congenital heart defect

OBJECTIVE

To evaluate comprehensively, using chromosomal microarray analysis (CMA) and exome sequencing (ES), the prevalence of chromosomal abnormalities and sequence variants in unselected fetuses with congenital heart defect (CHD) and to evaluate the potential diagnostic yields of CMA and ES for different CHD subgroups.

METHODS

This was a study of 360 unselected singleton fetuses with CHD detected by echocardiography, referred to our department for genetic testing between February 2018 and December 2019. We performed CMA, as a routine test for aneuploidy and copy number variations (CNV), and then, in cases without aneuploidy or pathogenic CNV on CMA, we performed ES.

RESULTS

Overall, positive genetic diagnoses were made in 84 (23.3%) fetuses: chromosomal abnormalities were detected by CMA in 60 (16.7%) and sequence variants were detected by ES in a further 24 (6.7%) cases. The detection rate of pathogenic and likely pathogenic genetic variants in fetuses with non-isolated CHD (32/83, 38.6%) was significantly higher than that in fetuses with isolated CHD (52/277, 18.8%) (P < 0.001), this difference being due mainly to the difference in frequency of aneuploidy between the two groups. The prevalence of a genetic defect was highest in fetuses with an atrioventricular septal defect (36.8%), ventricular septal defect with or without atrial septal defect (28.4%), conotruncal defect (22.2%) or right ventricular outflow tract obstruction (20.0%). We also identified two novel missense mutations (c.2447G>C, p.Arg816Pro; c.1171C>T, p.Arg391Cys) and a new phenotype caused by variants in PLD1.

CONCLUSIONS

Chromosomal abnormalities were identified in 16.7% and sequence variants in a further 6.7% of fetuses with CHD. ES should be offered to all pregnant women with a CHD fetus without chromosomal abnormality or pathogenic CNV identified by CMA, regardless of whether the CHD is isolated. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Choroid Plexus Cysts: Single Nucleotide Polymorphism Array Analysis of Associated Genetic Anomalies and Resulting Obstetrical Outcomes

Objective

Choroid plexus cysts (CPC) are pseudocysts in the fetal choroid plexus and can be detected during ultrasound examination. However, the etiology of fetuses with CPC is still unknown. This study aimed to evaluate the genetic anomalies of fetuses with CPC using single nucleotide polymorphism (SNP) array analysis, as well as their obstetrical outcomes.

Patients and Methods

Among 201 fetuses, 108, 69, and 24 had isolated CPC (iCPC), CPC with sonographic soft markers, and CPC with sonographic structural malformations, respectively. All fetuses underwent conventional karyotyping analysis and SNP array analysis.

Results

Among 201 fetuses with CPC, 15 had chromosomal abnormalities (7.5%, 15/201), including nine fetuses with trisomy 18. Further, SNP array results were consistent with the conventional karyotype analysis and additionally revealed 6.0% (12/201) abnormal copy number variations (CNVs). The rates of pathogenic CNVs in fetuses with iCPC, CPC combined with sonographic soft markers, and CPC combined with sonographic structural malformations were 6.5%, 6.0%, and 45.8%, respectively, with significant differences among the groups.

Conclusion

The results of the SNP array affected the obstetrical outcomes. CPC is thus associated with pathogenic CNVs in approximately 10.9% of cases. Therefore, SNP array should be offered for prenatal testing of fetuses with CPC.

SNP Array as a Tool for Prenatal Diagnosis of Congenital Heart Disease Screened by Echocardiography: Implications for Precision Assessment of Fetal Prognosis

Objective

This study aimed to examine the effectiveness of the SNP array for the prenatal diagnosis of congenital heart disease (CHD) screened by echocardiography.

Patients and Methods

A total of 356 pregnant women with fetal congenital heart malformations revealed by echocardiography at the Center for Prenatal Diagnosis of Fujian Maternal and Children Hospital during the period from November 2016 through July 2019 were recruited. The fetuses were assigned into three cohorts, including 142 with a single cardiac malformation, 106 with multiple cardiac malformations and 108 with cardiac and extracardiac malformations. All fetuses underwent chromosomal karyotyping and SNP array simultaneously, and the effectiveness of the SNP array for the prenatal diagnosis of CHD was evaluated.

Results

The overall prevalence of abnormal karyotypes was 9.3% among the 356 fetuses with CHD, and a higher proportion was found in fetuses with cardiac and extracardiac malformations (18.5%) than in those with single (5.6%) or multiple cardiac malformations (4.7%) (P<0.05). Consistent with karyotype analysis, SNP array detected an additional 25 fetuses with pathogenic copy number variations (CNVs), seven with variant of unknown significance (VOUS) and seven with benign CNVs, and a lower proportion of abnormal CNV was found in fetuses with a single cardiac malformation (4.2%) than in those with multiple cardiac malformations (9.4%) or cardiac and extracardiac malformations (14.8%) (P<0.05). Among the 33 fetuses with chromosomal abnormality, postnatal follow-up showed termination of pregnancy in 25 with pathogenic CNVs, one with VOUS, and six with normal karyotypes and SNP array findings but severe multiple malformations by ultrasonography.

Conclusion

SNP array increases the overall detection of abnormal CNVs by 9%, which improves the detection of CNVs associated with CHD. SNP array may serve as a tool for prenatal diagnosis of CHD that facilitates the discovery of pathogenic genes associated with CHD and provide valuable insights into the precision assessment of fetal prognosis during the prenatal counseling.

What have we learned from 691 prenatal chromosomal microarrays for ventricular septal defects?

INTRODUCTION

Ventricular septal defect (VSD) represents the most common type of congenital cardiac anomaly, affecting more than 1 in 300 live births. The objective of this study was to examine the incidence and nature of abnormal chromosomal microarray analysis (CMA) results in a large cohort of pregnancies with VSD.

MATERIAL AND METHODS

Data acquisition was performed through the Ministry of Health computerized database. All CMA results performed due to VSD during 2013-2017 were included. The rates of clinically significant CMA results of cases with isolated and non-isolated VSD were compared with two control populations-a systematic review of 9272 pregnancies and a local cohort of 5541 fetuses with normal ultrasound.

RESULTS

Overall, 691 CMA analyses performed due to a sonographic indication of VSD were detected. Of 568 pregnancies with isolated VSD, eight (1.4%) clinically significant copy number variants were detected, a nonsignificant difference compared with low risk pregnancies. Of the 123 pregnancies with non-isolated VSDs, 18 (14.6%) clinically significant CMA results were detected, a considerably increased risk compared with control pregnancies. Karyotype-detectable anomalies constituted 12 of the 18 abnormal CMA results in non-isolated VSD group (66.7%), a significantly higher proportion compared with 2 of 8 (25%) in isolated VSD cohort.

CONCLUSIONS

The outcomes of our study, representing the largest number of CMA results in pregnancies with VSD, suggest that the rate of abnormal CMA findings in isolated VSD does not differ from pregnancies with normal ultrasound. This observation is true for populations undergoing routine common trisomy screening tests and early sonographic evaluation, as well as widely available non-invasive prenatal screening. Conversely, CMA analysis yields a high detection rate in pregnancies with non-isolated VSD. Our results question the recommendation to perform invasive prenatal testing for CMA in pregnancies with isolated VSD.

Fetal congenital heart disease: Associated anomalies, identification of genetic anomalies by single-nucleotide polymorphism array analysis, and postnatal outcome

BACKGROUND

Congenital heart disease (CHD) is one of the most common birth defects; however, the mechanisms underlying its development are poorly understood. Recently, heritable genetic factors, including copy number variations (CNVs) and single nucleotide polymorphisms (SNPs), have been implicated in its etiology. The aim of this study was to investigate the utility of a SNP array for the prenatal diagnosis of CHD and the improvement of prenatal genetic counseling and to compare this approach to traditional chromosome analysis.

METHODS

One hundred and fortysix cases of CHD detected by prenatal echocardiography were analyzed. Of these, 110 were isolated CHD and 36 were of CHD with extracardiac defects. SNP analysis was performed using the Affymetrix CytoScan HD platform, which was followed by karyotype analysis. All annotated CNVs were validated by fluorescence in situ hybridization.

RESULTS

Karyotype analysis identified chromosomal abnormalities in 19 of 146 cases. In addition to the 15 chromosomal abnormalities that were consistent with the results of karyotype analysis, the SNP array identified abnormal CNVs in an additional 15.2% (22/145) cases; of these, 15 were pathogenic CNVs, three were variations of uncertain clinical significance, and four were benign CNVs. The rates at which the SNP array detected pathogenic CNVs differed significantly between cases of isolated CHD and CHD with extracardiac defects (13.6% vs. 72.2%, P = .001). The results of the SNP array also affected the rate of pregnancy termination.

CONCLUSION

Combining SNP array with cytogenetic analyses is particularly effective for identifying chromosomal abnormalities in CNVs in fetuses with CHD, which also affects obstetrical outcomes.

Chromosomal abnormalities and copy number variations in fetal ventricular septal defects

Background

This study aimed to evaluate the applicability of chromosomal microarray analysis (CMA), rather than traditional chromosome analysis, in prenatal diagnosis of ventricular septal defects (VSDs) for superior prenatal genetic counseling and to reveal a potential correlation between submicroscopic chromosomal aberrations and VSDs.

Results

Among the 151 VSD cases, 79 (52.3%) had isolated defects and 72 (47.7%) had additional ultrasound anomalies. Karyotype analysis identified 16 chromosomal abnormalities. Besides the 14 cases of chromosome abnormalities consistent with karyotype analysis, CMA identified an additional 20 cases (13.2%) of abnormal copy number variations (CNVs), of which 13 were pathogenetic CNVs, 5 were variations of uncertain clinical significance (VOUS) and 2 were benign CNVs. The detection rate of pathogenic CNVs in non-isolated-VSDs was significantly higher than that in isolated-VSDs (36.1% (26/72) vs. 1.3% (1/79), p = 0.001). We also found that CMA results indicating pathogenic abnormalities affected the rate of pregnancy termination.

Conclusions

This study showed that CMA combined with cytogenetic analysis is particularly effective in identifying CNVs in fetuses with VSDs and can have an effect on obstetrical outcomes. The elucidation of the etiology of VSDs suggested that gene mutations or other factors may be implicated.

Prenatal diagnosis by chromosomal microarray analysis

Chromosomal microarray analysis (CMA) is performed either by array comparative genomic hybridization or by using a single nucleotide polymorphism array. In the prenatal setting, CMA is on par with traditional karyotyping for detection of major chromosomal imbalances such as aneuploidy and unbalanced rearrangements. CMA offers additional diagnostic benefits by revealing sub-microscopic imbalances or copy number variations that are too small to be seen on a standard G-banded chromosome preparation. These submicroscopic imbalances are also referred to as microdeletions and microduplications, particularly when they include specific genomic regions that are associated with clinical sequelae. Not all microdeletions/duplications are associated with adverse clinical phenotypes and in many cases, their presence is benign. In other cases, they are associated with a spectrum of clinical phenotypes that may range from benign to severe, while in some situations, the clinical significance may simply be unknown. These scenarios present a challenge for prenatal diagnosis, and genetic counseling prior to prenatal CMA greatly facilitates delivery of complex results. In prenatal diagnostic samples with a normal karyotype, chromosomal microarray will diagnose a clinically significant subchromosomal deletion or duplication in approximately 1% of structurally normal pregnancies and 6% with a structural anomaly. Pre-test counseling is also necessary to distinguish the primary differences between the benefits, limitations and diagnostic scope of CMA versus the powerful but limited screening nature of non-invasive prenatal diagnosis using cell-free fetal DNA.

Clinical value of chromosomal microarray analysis in prenatally diagnosed dextro-transposition of the great arteries

Objectives: To evaluate the usefulness of chromosomal microarray analysis (CMA) in fetuses with dextro-transposition of the great arteries (d-TGA).Methods: Thirty-two fetuses with d-TGA were examined for submicroscopic copy number variations (CNVs) using CMA.Results: Among the 32 d-TGA fetuses, 23 had isolated lesions (71.9%) and nine had other cardiac or extracardiac anomalies (28.1%). CNVs were detected in 16/32 (50%) of the fetuses, including benign CNVs detected in nine fetuses (28.1%), pathogenic CNVs detected in three fetuses (9.4%), and variants of unknown significance (VOUS) detected in four fetuses (12.5%). There was no significant difference in the detection rates of pathogenic CNVs between the isolated and nonisolated groups. All four VOUS were found in the nonisolated group.Conclusion: CMA might be an effective tool for identifying submicroscopic chromosomal aberrations in fetuses with d-TGA.

Clinical application of chromosomal microarray analysis for the prenatal diagnosis of chromosomal abnormalities and copy number variations in fetuses with congenital heart disease

OBJECTIVES

This study aimed to determine chromosomal abnormalities and copy number variations (CNVs) in fetuses with congenital heart disease (CHD) by chromosomal microarray analysis (CMA).

METHODS

One hundred and ten cases with CHD detected by prenatal echocardiography were enrolled in the study; 27 cases were simple CHDs, and 83 were complex CHDs. Chromosomal microarray analysis was performed on the Affymetrix CytoScan HD platform. All annotated CNVs were validated by quantitative PCR.

RESULTS

Chromosomal microarray analysis identified 6 cases with chromosomal abnormalities, including 2 cases with trisomy 21, 2 cases with trisomy 18, 1 case with trisomy 13, and 1 unusual case of mosaic trisomy 21. Pathogenic CNVs were detected in 15.5% (17/110) of the fetuses with CHDs, including 13 cases with CHD-associated CNVs. We further identified 10 genes as likely novel CHD candidate genes through gene functional enrichment analysis. We also found that pathogenic CMA results impacted the rate of pregnancy termination.

CONCLUSIONS

This study shows that CMA is particularly effective for identifying chromosomal abnormalities and CNVs in fetuses with CHDs as well as having an effect on obstetrical outcomes. The elucidation of the genetic basis of CHDs will continue to expand our understanding of the etiology of CHDs.

Prenatal chromosomal microarray analysis in fetuses with congenital heart disease: a prospective cohort study

BACKGROUND

Currently, chromosomal microarray analysis is considered the first-tier test in pediatric care and prenatal diagnosis. However, the diagnostic yield of chromosomal microarray analysis for prenatal diagnosis of congenital heart disease has not been evaluated based on a large cohort.

OBJECTIVE

Our aim was to evaluate the clinical utility of chromosomal microarray as the first-tier test for chromosomal abnormalities in fetuses with congenital heart disease.

STUDY DESIGN

In this prospective study, 602 prenatal cases of congenital heart disease were investigated using single nucleotide polymorphism array over a 5-year period.

RESULTS

Overall, pathogenic chromosomal abnormalities were identified in 125 (20.8%) of 602 prenatal cases of congenital heart disease, with 52.0% of them being numerical chromosomal abnormalities. The detection rates of likely pathogenic copy number variations and variants of uncertain significance were 1.3% and 6.0%, respectively. The detection rate of pathogenic chromosomal abnormalities in congenital heart disease plus additional structural anomalies (48.9% vs 14.3%, P < .0001) or intrauterine growth retardation group (50.0% vs 14.3%, P = .044) was significantly higher than that in isolated congenital heart disease group. Additionally, the detection rate in congenital heart disease with additional structural anomalies group was significantly higher than that in congenital heart disease with soft markers group (48.9% vs 19.8%, P < .0001). No significant difference was observed in the detection rates between congenital heart disease with additional structural anomalies and congenital heart disease with intrauterine growth retardation groups (48.9% vs 50.0%), congenital heart disease with soft markers and congenital heart disease with intrauterine growth retardation groups (19.8% vs 50.0%), or congenital heart disease with soft markers and isolated congenital heart disease groups (19.8% vs 14.3%). The detection rate in fetuses with congenital heart disease plus mild ventriculomegaly was significantly higher than in those with other types of soft markers (50.0% vs 15.6%, P < .05).

CONCLUSION

Our study suggests chromosomal microarray analysis is a reliable and high-resolution technology and should be used as the first-tier test for prenatal diagnosis of congenital heart disease in clinical practice.