Diagnosis, characterization and outcome of congenitally corrected transposition of the great arteries in the fetus: a multicenter series of 30 cases

Congenitally Corrected Transposition of the Great Arteries in Utero: Morphological Spectrum, Outcomes and Pitfalls in Fetal Diagnosis

Congenitally corrected transposition of the great arteries (ccTGA) is a rare malformation with diverse morphology. We assessed features of fetuses with ccTGA and evaluated neonatal and pediatric outcomes. This was a retrospective review of fetuses with ccTGA at Birmingham Women's and Children's Hospital born from 2005 to 2019. Of thirty-six fetuses identified, six had unavailable prenatal data, one was postnatally diagnosed with isomerism and 29 fetuses were evaluated. ccTGA without associated cardiac lesions was found in 28% (8/29), ccTGA with significant VSD in 31% (9/29), ccTGA with pulmonary obstruction in 24% (7/29) and ccTGA with complex anomalies in 17% (5/29). Tricuspid regurgitation (TR) was observed in 17% (5/29) and heart block (HB) in 10% (3/29) prenatally. Six, that is 21% underwent genetic testing of which one was abnormal. Five extra-cardiac anomalies were reported prenatally and postnatally. Pregnancy was discontinued in five, of which two had moderate TR. There were thirty-one liveborn. Coarctation of the aorta was found in five postnatally but not suspected prenatally. In one, pulmonary stenosis was underestimated; otherwise, prenatal morphology was confirmed. Cardiac interventions were performed in 77% (24/31) liveborn with 39% (12/31) undergoing neonatal intervention. Overall, 6/31 liveborn died including all three with prenatal heart block and one with TR. Estimated survival for all liveborn at 1, 5 and 10 years was 87% (95% CI 76-100%), 83% (95% CI 72-98%) and 80% (95% CI 66-96%) respectively. Accurate prenatal diagnosis of ccTGA is critical for counseling. Early outcomes are favorable with 77% of liveborn undergoing surgery. Fetuses with prenatal diagnosis of complex associated abnormalities, HB and TR appear to do less well.

Prenatal transposition of great arteries diagnosis and management: a Chinese single-center study

Objective

This study aimed to assess the diagnostic value of prenatal echocardiography for identifying transposition of the great arteries (TGA) during pregnancy and evaluating the associated outcomes.

Methods

We conducted a retrospective analysis of 121 prenatally diagnosed patients with TGA at our hospital between January 2012 and September 2022. This analysis included prenatal ultrasound, prenatal screening, clinical management and follow-up procedures.

Results

Among the 103 fetuses considered in the study, 90 (87.4%) were diagnosed with complete transposition of the great arteries (D-TGA), while 13 (12.6%) exhibited corrected transposition of the great arteries (CC-TGA). Diagnoses were distributed across the trimester, with 8 D-TGA and 2 CC-TGA patients identified in the first trimester, 68 D-TGA patients and 9 CC-TGA patients in the second trimester, and 14 D-TGA and 2 CC-TGA patients referred for diagnosis in the third trimester. Induction of labour was pursued for 76 D-TGA patients (84.4%) and 11 CC-TGA patients (84.6%), and 14 D-TGA patients (15.6%) and 2 CC-TGA patients (15.4%) continued pregnancy until delivery. Among the D-TGA patients, 9 fetuses (10.0%) underwent surgery, two of which were inadvertent fatality, while the remaining seven experienced positive outcomes. Additionally, seven TGA patients received palliative care, leading to four fatalities among D-TGA patients (5.2%), whereas 1 D-TGA patients and 2 CC-TGA patients survived.

Conclusion

This study underscores the feasibility of achieving an accurate prenatal diagnosis of TGA during early pregnancy. The utility of prenatal ultrasound in the development of personalized perinatal plans and the application of multidisciplinary treatment during delivery are conducive.

A case report of upgrading to cardiac resynchronization therapy in a patient with congenitally corrected transposition of great arteries and dextrocardia

Background

Congenitally corrected transposition of the great arteries (CCTGA) is a rare congenital heart anomaly. Physiological correction may be associated with a long pre-symptomatic period in many patients and delayed accidental diagnosis. Additional related congenital malformations may increase the complexity of cardiac interventions.

Case summary

A 59-year-old man with known dextrocardia, situs viscerum inversus, and CCTGA was scheduled for upgrading of a dual-chamber pacemaker to cardiac resynchronization therapy to treat heart failure related to a progressive systolic dysfunction of the systemic right ventricle (RV). Because of the specific anatomy of this patient, the therapeutic procedure was complicated by the cannulation of the Marshall vein. Nevertheless, the left ventricular lead was successfully implanted into the coronary sinus lateral branch. At the 3-month follow-up, the patient remarkably reported a significant functional improvement, despite no favourable reverse remodelling of the systemic RV.

Discussion

Upgrade of a pacemaker to biventricular pacing was feasible in this patient, who had CCTGA and dextrocardia, which resulted in symptomatic improvement at follow-up. Pre-implant contrast cardiac computed tomography angiography was essential for visualizing the venous-specific anatomy in this patient, who suffered from congenital heart disease. Conduction system pacing represents a potential alternative for the patient to prevent or treat pacing-related heart failure.

Congenitally corrected transposition: not correct at all

PURPOSE OF REVIEW

Congenitally corrected transposition of the great arteries is a rare congenital defect with several management options. Disagreement continues on strategies, such as anatomic repair, physiologic repair or observation-only. This review discusses recent data that provide further guidance for clinical decision-making.

RECENT FINDINGS

New data provide greater insights into practice patterns and outcomes. Recent data from high-volume centers show progressively high rates of systemic right ventricle dysfunction over time with lower rates of systemic left ventricle dysfunction following anatomic repair; there is a statistical trend towards better survival of anatomic repair patients. Data comparing anatomic repair to observation showed that anatomic repair patients had a lower hazard of reaching a composite adverse outcome. These complex operations are predominantly performed at a small subset of congenital heart surgery centers.

SUMMARY

Anatomic repair compared with physiologic repair may have better outcomes, although there are relatively high rates of morbidity for both approaches. In the patient without associated lesions, nonsurgical management can have excellent outcomes but is complicated by right ventricular failure over time. Multicenter research will help determine risk factors for bad outcomes; management at high volume, experienced centers will probably be beneficial for this complex patient population.

Prenatal Diagnosis and Outcome of Congenital Corrected Transposition of the Great Arteries - A Multicenter Report of 69 Cases

OBJECTIVE

 Congenital corrected transposition of the great arteries (ccTGA) is a rare congenital cardiac anomaly which remains difficult to diagnose prenatally. We aim to investigate the natural history, associated anomalies and the outcome of patients in prenatally diagnosed ccTGA.

METHOD

 This was an international multicenter retrospective analysis of fetuses with a diagnosis of ccTGA from 2002 to 2017. We reviewed clinical and echocardiographic databases of seven centers. Anatomic survey and fetal echocardiography were performed according to international guidelines of ISUOG.

RESULTS

 We considered 69 fetuses with prenatally suspected ccTGA. There was an overall survival rate of 91 % among 54 patients with a confirmed diagnosis. Survival to live birth was 96 % (52/54) and survival on an intention-to-treat basis was 94 % (49/52). The mean gestational age at the time of diagnosis was 25.6 ± 5.9 weeks of gestation. In 7 out of 54 fetuses (13 %), ccTGA was an isolated finding. Dextro/mesocardia was present in 15 cases (27.8 %). Intracardiac anomalies were present in 46/54 cases (85.2 %) with the most frequent anomaly being a ventricular septal defect present in 41 fetuses (75.9 %). Complete heart block was diagnosed in 10 cases (18.5 %). Extracardiac anomalies were observed in 9 out of 54 cases (16.7 %). Prenatal karyotyping of the fetus was available in 30/54 (55.6 %) cases with chromosomal anomalies in 4/30 (13.3 %).

CONCLUSION

 ccTGA is a rare cardiac anomaly often accompanied by a variable spectrum of further intracardiac abnormalities. Accurate diagnosis of ccTGA, which can be integrated into parental counselling, is feasible with a favorable short-term outcome for affected neonates.

Prenatal diagnosis, associated findings and postnatal outcome in fetuses with congenitally corrected transposition of the great arteries

Purpose

To analyze anatomic features and associated malformations in 37 prenatally detected cases of congenitally corrected transposition of the great arteries (ccTGA) and to evaluate the prenatal course, neonatal outcome and mid-term follow-up.

Methods

Retrospective analysis of prenatal ultrasound of 37 patients with ccTGA in two tertiary centers between 1999 and 2019. All fetuses received fetal echocardiography and a detailed anomaly scan. Postnatal outcome and follow-up data were retrieved from pediatric reports.

Results

Isolated ccTGA without associated cardiac anomalies was found in 13.5% (5/37), in all other fetuses additional defects such as VSD (73.0%), pulmonary obstruction (35.1%), tricuspid valve anomalies (18.9%), aortic arch anomalies (13.5%), ventricular hypoplasia (5.4%) or atrioventricular block (5.4%) were present. The rate of extracardiac malformations or chromosomal aberrations was low. There were 91.9% (34/37) live births and postnatal survival rates reached 91.2% in a mean follow-up time of 4.98 years. The prenatal diagnosis of ccTGA was confirmed postnatally in all but one documented live birth and the prenatal counselling regarding the expected treatment after birth (uni- versus biventricular repair) was reassured in the majority of cases. The postnatal intervention rate was high, 64.7% (22/34) received surgery, the intervention-free survival was 36.7%, 35.0% and 25.0% at 1 month, 1 year and 10 years, respectively.

Conclusions

ccTGA is a rare heart defect often associated with additional heterogeneous cardiac anomalies that can be diagnosed prenatally. The presented study demonstrates a favorable outcome in most cases but the majority of patients require surgical treatment early in life.

Prenatal diagnosis of transposition of the great arteries: an updated review

Simple transposition of the great arteries (TGA) is a cyanotic heart disease that accounts for 5% to 7% of all congenital heart diseases. It is commonly underdiagnosed in utero, with prenatal detection rates of less than 50%. Simple TGA is characterized by ventriculoarterial discordance, atrioventricular concordance, and a parallel relationship of TGA. The prenatal diagnosis of TGA influences postnatal outcomes and therefore requires planned delivery and perinatal management. For these reasons, it is important to identify the key ultrasound markers of TGA to improve the prenatal diagnosis and consequently provide perinatal assistance. The presence of two vessels instead of three in the three-vessel tracheal view, a parallel course of TGA, and identification of the origin of each of TGA are the key markers for diagnosing TGA. In addition to the classical ultrasound signs, other two-dimensional ultrasound markers such as an abnormal right convexity of the aorta, an I-shaped aorta, and the "boomerang sign" may also be used to diagnose TGA in the prenatal period. When accessible, an automatic approach using four-dimensional technologies such as spatio-temporal image correlation and sonographically-based volume computer-aided analysis may improve the prenatal diagnosis of TGA. This study aimed to review the ultrasound markers that can be used in the antenatal diagnosis of TGA, with a focus on the tools used by ultrasonographers, the obstetric and fetal medicine team, and perinatal cardiologists to improve the diagnosis of this condition.

Prenatal diagnosis of congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries is a rare and complex congenital heart disease. It essentially occurs with atrioventricular and ventriculoarterial discordance, in which the great vessels become parallel. Cases of corrected transposition of the great arteries are more frequently associated with other cardiac anomalies. In the fetus, corrected transposition of the great arteries may not be diagnosed on obstetric cardiac ultrasound, especially in the absence of other cardiac malformations (isolated corrected transposition of the great arteries). In this manuscript, we describe a case of isolated corrected transposition of the great arteries diagnosed in utero, and highlight the clues to make this diagnosis.

Ventricular fibrillation in congenitally corrected transposition of great arteries treated with pacing: a case report

Background

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease which may present with sudden death from malignant arrhythmias including complete heart block and ventricular tachyarrhythmias as late complications. Only few cases about ventricular tachyarrhythmias, usually in those with markedly depressed systemic ventricular function, have been reported.

Case summary

A 26-year-old woman with a known history of CCTGA presented to the emergency department with palpitations and breathlessness for 3–4 weeks and worsening symptoms for 8 h. She had a history of ventricular septal defect repair 14 years ago. Her initial presentation electrocardiogram demonstrated high degree atrioventricular block with a ventricular rate of 44 b.p.m. She had two episodes of complete syncope during this hospitalization, both required external defibrillation due to documented bradycardia-dependent ventricular fibrillations. Her two-dimensional echocardiography study confirmed the diagnosis of CCTGA with preserved systolic ventricular function. She underwent urgent temporal pacing wire placement with a paced ventricular rate at 90 b.p.m. Having thoroughly reviewed the arrhythmia events and discussed with the patient about the option of defibrillator vs. pacemaker therapy a decision was made upon her request for dual-chamber pacemaker implantation. She was discharged home uneventfully 3 days after hospital presentation and has been physically active at 3-, 6-, and 9-month follow-ups.

Discussion

Our case illustrates the individualized clinical decision making in choosing device therapy for a rare congenital heart disease presented with malignant arrhythmia. Careful history taking, open communication, and closely planned long-term follow-up will be essential in caring for such patients.

Postnatal Outcome Following Prenatal Diagnosis of Discordant Atrioventricular and Ventriculoarterial Connections

Discordant atrioventricular and ventriculoarterial connection(s) (DAVVAC) are a rare group of congenital heart lesions. DAVVAC can be isolated or associated with a variety of other cardiac abnormalities. Previous studies examining the outcome of prenatally diagnosed DAVVAC have described only fetal and early postnatal outcome in small cohorts. We aimed to describe the medium-term outcome of these fetuses. Cases were identified by searching the fetal cardiac databases of two centers. Follow-up data were collected from the electronic patient records. We identified 98 fetuses with DAVVAC. 39 pregnancies were terminated and 51 resulted in a liveborn infant. Postnatal data were available for 43 patients. The median length of follow-up was 9.5 years (range 36 days to 22.7 years). The overall 5-year survival of the cohort was 80% (95% confidence interval 74-86%), no deaths were seen after this period. Associated cardiac lesions had a significant effect on both survival and surgery-free survival. Isolated DAVVAC and DAVVAC with pulmonary stenosis ± ventricular septal defect had a low mortality (89% and 100% 5-year survival, respectively). Poorer survival was seen in the group with Ebstein's anomaly of the tricuspid valve, and other complex cardiac abnormalities. Antenatal tricuspid regurgitation had a significant negative impact on postnatal survival. In conclusion, the short- and medium-term outlook for fetuses with isolated DAVVAC, and those with DAVVAC and pulmonary stenosis are good. Antenatal risk factors for postnatal mortality include Ebstein's anomaly of the tricuspid valve, especially if associated with tricuspid regurgitation, and the presence of complex associated lesions.

Pulmonary Artery Banding for Congenitally Corrected Transposition of the Great Arteries With Hydrops Fetalis: A Case Report

At 32 weeks of gestation, a male fetus with congenitally corrected transposition of the great arteries developed hydrops fetalis caused by a combination of mitral valve regurgitation and tricuspid valve regurgitation (TR). We performed a pulmonary artery banding (PAB) at 108 days old for gradually progressing TR, after confirming that a balloon dilatation test in the main pulmonary artery reduced TR. As the patient grew, the PAB became tighter and systolic blood pressure in the morphological left ventricle increased. At present, the patient is waiting for a double switch operation.

Congenitally Corrected Transposition of the Great Arteries: Anatomic, Physiologic Repair, and Palliation

Congenitally corrected transposition of the great arteries (ccTGA) is a lesion that rarely occurs in isolation. The presenting physiology of ccTGA is predominantly secondary to the concurrent cardiac lesions; however, as the child ages, unrepaired ccTGA results in progressive failure of the morphologic right ventricle under the strain of maintaining a systemic pressure. Repair of ccTGA was initially focused on rectification of the underlying physiologic aberrations, but in recent years, the focus of repair has shifted toward anatomic correction to avoid failure of the morphologic right ventricle. This anatomic repair is commonly associated with improved long-term mortality at the cost of increased short-term mortality. Key preoperative considerations such as morphologic left ventricular pressure, tricuspid valve competency, and out flow tract obstructions can assist in determining the optimal repair for individual patients. An alternative, single ventricle, pathway has been proposed for any patient without optimal preoperative anatomy to improve long-term survival. Adjunctive repair options including pulmonary artery banding and one-and-a-half ventricle repairs have also been proposed to augment the survival curves.

Prenatal diagnosis of congenital heart disease: A review of current knowledge

This article reviews important features to improve the diagnosis of congenital heart disease (CHD) by applying ultrasound in prenatal cardiac screening. As low and high-risk pregnancies for CHD are subject to routine obstetric ultrasound, the diagnosis of structural heart defects represents a challenge that involves a team of specialists and subspecialists on fetal ultrasonography. In this review, the images highlight normal anatomy of the heart as well as pathologic cases consistent with cardiac malposition and isomerism, septal defects, pulmonary stenosis/atresia, aortic malformations, hypoplastic left ventricle, conotruncal anomalies, tricuspid dysplasia, and Ebstein’s anomaly, and univentricular heart, among other congenital cardiovascular defects. Anatomical details of most CHD in fetuses were provided by two-dimensional (2D) ultrasound with higher quality imaging, enhancing diagnostic accuracy in a variety of CHD. Moreover, the accuracy of the cardiac defects in obstetrics ultrasound improves the outcome of most CHD, providing planned delivery, aided genetic counseling, and perinatal management.

Diagnosis and treatment of fetal cardiac disease: a scientific statement from the American Heart Association

BACKGROUND

The goal of this statement is to review available literature and to put forth a scientific statement on the current practice of fetal cardiac medicine, including the diagnosis and management of fetal cardiovascular disease.

METHODS AND RESULTS

A writing group appointed by the American Heart Association reviewed the available literature pertaining to topics relevant to fetal cardiac medicine, including the diagnosis of congenital heart disease and arrhythmias, assessment of cardiac function and the cardiovascular system, and available treatment options. The American College of Cardiology/American Heart Association classification of recommendations and level of evidence for practice guidelines were applied to the current practice of fetal cardiac medicine. Recommendations relating to the specifics of fetal diagnosis, including the timing of referral for study, indications for referral, and experience suggested for performance and interpretation of studies, are presented. The components of a fetal echocardiogram are described in detail, including descriptions of the assessment of cardiac anatomy, cardiac function, and rhythm. Complementary modalities for fetal cardiac assessment are reviewed, including the use of advanced ultrasound techniques, fetal magnetic resonance imaging, and fetal magnetocardiography and electrocardiography for rhythm assessment. Models for parental counseling and a discussion of parental stress and depression assessments are reviewed. Available fetal therapies, including medical management for arrhythmias or heart failure and closed or open intervention for diseases affecting the cardiovascular system such as twin-twin transfusion syndrome, lung masses, and vascular tumors, are highlighted. Catheter-based intervention strategies to prevent the progression of disease in utero are also discussed. Recommendations for delivery planning strategies for fetuses with congenital heart disease including models based on classification of disease severity and delivery room treatment will be highlighted. Outcome assessment is reviewed to show the benefit of prenatal diagnosis and management as they affect outcome for babies with congenital heart disease.

CONCLUSIONS

Fetal cardiac medicine has evolved considerably over the past 2 decades, predominantly in response to advances in imaging technology and innovations in therapies. The diagnosis of cardiac disease in the fetus is mostly made with ultrasound; however, new technologies, including 3- and 4-dimensional echocardiography, magnetic resonance imaging, and fetal electrocardiography and magnetocardiography, are available. Medical and interventional treatments for select diseases and strategies for delivery room care enable stabilization of high-risk fetuses and contribute to improved outcomes. This statement highlights what is currently known and recommended on the basis of evidence and experience in the rapidly advancing and highly specialized field of fetal cardiac care.

[About six observations of double discrepancy of the heart: feasibility of prenatal diagnosis?]

The double discrepancy (DD) is an exceptional cardiopathy, manifested by atrioventricular and ventriculo-arterial discordances. DD is rarely diagnosed in the antenatal period and is often found in adults when cardiac complications occur. We describe six cases of DD, the different forms, their ultrasound semiology, and the assessment of prognosis, correlated with the existence of associated cardiac anomalies.

Atrial fibrillation-induced cardiac shock: first manifestation of a congenitally corrected transposition of the great arteries in a 45-year-old man

Background. The congenitally corrected transposition of the great arteries (L-TGA) is a very rare congenital heart defect, which often remains undetected for several decades of life. Case Presentation. We report on a 45-year-old man without prior history of heart disease, presenting with cardiac shock related to a first episode of tachycardic atrial fibrillation. The diagnostic work-up identified a L-TGA as the underlying cause for acute heart failure. Discussion. L-TGA is a very rare congenital heart defect, which is characterized by an atrioventricular as well as a ventriculoarterial discordance. By this means, the physiological sequence of pulmonary and systemic circulation is still maintained. On the basis of an ongoing strain of the right ventricle, which has to carry the burden of the systemic blood pressure, after more than four decades without symptoms, acute heart failure was triggered by a tachycardic atrial fibrillation.

Congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries (cTGA) is an uncommon cardiac malformation characterized by discordant atrioventricular and ventriculoarterial connections. Most cases of cTGA are associated with cardiac anomalies. As the ventricular outflow tract may appear to arise correctly from the right and left ventricles, cases of cTGA with a mild associated anomaly are rarely detected prenatally. Parallel vessels are evident in cTGA, but this sign is also present in complete TGA. We report a case of cTGA diagnosed in utero at 29 weeks' gestation. The fetus was diagnosed as TGA and referred to our hospital at 28 weeks' gestation. cTGA was found at 29 weeks' gestation in our hospital, and no additional cardiac anomalies were seen prenatally. After birth, patent ductus arteriosus with bidirectional flow was present. Careful examination of the four-chamber view suggested atrioventricular discordance. Identification of a parallel course of the great vessels, with the aorta anterior and to the left of the pulmonary trunk (l-transposition), may help accurate prenatal diagnosis of cTGA.

The Natural History of Congenitally Corrected Transposition of the Great Arteries

The natural history of congenitally corrected transposition of the great arteries is of clinical/surgical importance once the fetus is born without heart block or signs of heart failure. Without significant tricuspid valve malformation, associated defects such as ventricular septal defect and left ventricular outflow obstruction can be repaired surgically. The mortality and long-term outcome appear to be linked strongly with the severity of tricuspid valve regurgitation. Some patients with an intact ventricular septum and no right ventricular dysfunction will live long lives without detection, and some women will successfully complete pregnancy.

Comparison of impact of prenatal versus postnatal diagnosis of congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries (CCTGA) in the absence of major cardiac anomalies is thought to have a good outcome, although this has not been well documented. The objective of the present study was to compare the characteristics and outcomes of patients with a prenatal diagnosis of CCTGA to the characteristics and outcomes of those diagnosed postnatally. The optimal outcome was defined as intervention-free survival. All patients with CCTGA diagnosed prenatally and postnatally from 1999 to 2006 at 2 tertiary care institutions were reviewed. Patients with a single ventricle, heterotaxy, or valvar atresia were excluded. The differences between groups were assessed using the t test and chi-square test. A total of 54 patients (16 prenatal with 14 live born and 39 postnatal) were included. The patients diagnosed prenatally were diagnosed at a median gestational age of 20 weeks (range 16 to 37). Two deaths in each group were due to heart failure. The intervention-free survival rate for the prenatal and postnatal groups at 1, 6, and 36 months was 79%, 45%, and 30% and 85%, 61%, and 23%, respectively (p = NS). Of 37 patients, 14 (38%) underwent an arterial switch plus atrial baffling so that the morphologic left ventricle supported the systemic circulation, and 6 (16%) underwent repair of associated lesions so the morphologic right ventricle supported the systemic circulation; 4 (11%) of the 37 patients had pacemaker only. Prenatal patients with >1 fetal echocardiogram (12 of 14) did not have progression before birth. In conclusion, CCTGA has a >70% risk of intervention in the first 3 years after birth. The outlook is guarded and has an important effect on prenatal counseling.

Outcome of fetal cardiac defects

PURPOSE OF REVIEW

The present review summarizes the prenatal and postnatal outcome of cardiac anomalies and sustained arrhythmias diagnosed during fetal life.

RECENT FINDINGS

The outcome of sustained fetal arrhythmias has improved with greater experience using Sotalol for atrial flutter, and digoxin and amiodarone for 1: 1 reciprocating tachycardia. The outcome of fetal conduction system disease secondary to maternal Sjögren's antibodies has noticeably improved with transplacental dexamethasone. The postnatal prognosis for atrioventricular block associated with left atrial isomerism, however, remains very bleak. Assessing the effect of prenatal diagnosis on the outcome of structural defects remains difficult because of the high number of extracardiac anomalies and chromosome defects in this group. Preoperative survival is improved, but postoperative mortality has not improved. One clear advantage of prenatal diagnosis is the selection of fetuses that may benefit from in-utero intervention to limit the progression of their disease or lessen its severity at birth.

SUMMARY

For the most part, postoperative mortality of structural cardiac defects is not significantly improved by prenatal diagnosis. In-utero management of tachyarrhythmias and conduction system disease has improved postnatal outcome, except for the fetus with atrioventricular block and left atrial isomerism.