Utility of fetal echocardiography after normal cardiac imaging findings on detailed fetal anatomic ultrasonography

Cardiovascular Complications of Down Syndrome: Scoping Review and Expert Consensus

Cardiovascular disease is a leading cause of morbidity and mortality in individuals with Down syndrome. Congenital heart disease is the most common cardiovascular condition in this group, present in up to 50% of people with Down syndrome and contributing to poor outcomes. Additional factors contributing to cardiovascular outcomes include pulmonary hypertension; coexistent pulmonary, endocrine, and metabolic diseases; and risk factors for atherosclerotic disease. Moreover, disparities in the cardiovascular care of people with Down syndrome compared with the general population, which vary across different geographies and health care systems, further contribute to cardiovascular mortality; this issue is often overlooked by the wider medical community. This review focuses on the diagnosis, prevalence, and management of cardiovascular disease encountered in people with Down syndrome and summarizes available evidence in 10 key areas relating to Down syndrome and cardiac disease, from prenatal diagnosis to disparities in care in areas of differing resource availability. All specialists and nonspecialist clinicians providing care for people with Down syndrome should be aware of best clinical practice in all aspects of care of this distinct population.

Utility of Screening Fetal Echocardiogram Following Normal Anatomy Ultrasound for In Vitro Fertilization Pregnancies

In vitro fertilization (IVF) is associated with a higher incidence of congenital heart disease, resulting in universal screening fetal echocardiograms (F-echo) even when cardiac structures on obstetric scan (OB-scan) are normal. Recent studies suggest that when OB-scan is normal, F-echo may add little benefit and increases cost and anxiety. We aim to determine the utility of screening F-echo in IVF pregnancies with normal cardiac anatomy on prior OB-scan. We conducted a retrospective chart review of IVF pregnancies referred for F-echo at the Seattle Children's Hospital between 2014 and 2020. OB-scan results and subspecialty of interpreting physician (Obstetrics = OB; Maternal Fetal Medicine = MFM; Radiology = Rads), F-echoes, and postnatal outcomes were reviewed. Cardiac anatomy on OB-scans was classified as complete if 4-chamber and outflow-tract views were obtained. Supplemental views (three-vessel and sagittal aortic arch views) on OB-scan were also documented. Of 525 IVF referrals, OB-scan reports were available for review in 411. Normal anatomy was demonstrated in 304 (74%) interpreted by OB (128; 42%), MFM (80; 26%), and Rads (96; 32%). F-echo was normal in 278 (91%). Of the 26 abnormal F-echo, none required intervention (17 muscular and 5 perimembranous ventricular septal defects, and 4 minor valve abnormalities). There was no difference in OB-scan accuracy for identifying normal cardiac anatomy when comparing 4-chamber and outflow-tract views vs. addition of supplemental views (91% vs 92% normal F-echo; p > 0.1). Evaluation of OB-scan accuracy by interpreting physician subspecialty demonstrated normal F-echo in 95%, 85%, and 92% (p = 0.95) as read by OB, MFM, and Rads, respectively. A majority of IVF referrals with normal cardiac anatomy visualized on OB-scan using 4-chamber and outflow-tract views resulted in normal F-echo, regardless of interpreting physician subspecialty or addition of supplemental views. Of the minority with abnormal F-echo, none required intervention. Consideration should be given to the cost/benefit of screening F-echo for the indication of IVF if normal cardiac anatomy is demonstrated on OB-scan.

Incremental Detection of Severe Congenital Heart Disease by Fetal Echocardiography Following a Normal Second Trimester Ultrasound Scan in Québec, Canada

Background:

The benefit of fetal echocardiograms (FE) to detect severe congenital heart diseases (SCHD) in the setting of a normal second-trimester ultrasound is unclear. We aimed to assess whether the increase in SCHD detection rates when FE are performed for risk factors in the setting of a normal ultrasound was clinically significant to justify the resources needed.

Methods:

This is a multicenter, population-based, retrospective cohort study, including all singleton pregnancies and offspring in Quebec (Canada) between 2007 and 2015. Administrative health care data were linked with FE clinical data to gather information on prenatal diagnosis of CHD, indications for FE, outcomes of pregnancy and offspring, postnatal diagnosis of CHD, cardiac interventions, and causes of death. The difference between the sensitivity to detect SCHD with and without FE for risk factors was calculated using generalized estimating equations with a noninferiority margin of 5 percentage points.

Results:

A total of 688 247 singleton pregnancies were included, of which 30 263 had at least one FE. There were 1564 SCHD, including 1071 that were detected prenatally (68.5%). There were 12 210 FE performed for risk factors in the setting of a normal second-trimester ultrasound, which led to the detection of 49 additional cases of SCHD over 8 years. FE referrals for risk factors increased sensitivity by 3.1 percentage points (95% CI, 2.3–4.0; P<0.0001 for noninferiority).

Conclusions:

In the setting of a normal second-trimester ultrasound, adding a FE for risk factors offered low incremental value to the detection rate of SCHD in singleton pregnancies. The current ratio of clinical gains versus the FE resources needed to screen for SCHD in singleton pregnancies with isolated risk factors does not seem favorable. Further studies should evaluate whether these resources could be better allocated to increase SCHD sensitivity at the ultrasound level, and to help decrease heterogeneity between regions, institutions and operators.

Concordance Between Obstetric Anatomic Ultrasound and Fetal Echocardiography in Detecting Congenital Heart Disease in High-risk Pregnancies

OBJECTIVES

To evaluate the concordance between second-trimester anatomic ultrasound and fetal echocardiography in detecting minor and critical congenital heart disease in pregnancies meeting American Heart Association criteria.

METHODS

We conducted a retrospective cohort study of pregnancies in which a second-trimester fetal anatomic ultrasound examination (18-26 weeks) and fetal echocardiography were performed between 2012 and 2018 at our institution based on American Heart Association recommendations. Anatomic ultrasound studies were interpreted by maternal-fetal medicine specialists and fetal echocardiographic studies by pediatric cardiologists. Our primary outcome was the proportion of critical congenital heart disease (CCHD) cases not detected by anatomic ultrasound but detected by fetal echocardiography. The secondary outcome was the proportion of total congenital heart disease cases missed by anatomic ultrasound but detected by fetal echocardiography. Neonatal medical records were reviewed for all pregnancies when obtained and available.

RESULTS

Overall, 722 studies met inclusion criteria. Anatomic ultrasound and fetal echocardiography were in agreement in detecting cardiac abnormalities in 681(96.1%) studies (κ = 0.803; P < .001). The most common diagnosis not identified by anatomic ultrasound was a ventricular septal defect, accounting for 9 of 12 (75%) missed congenital heart defects. Of 664 studies with normal cardiac findings on the anatomic ultrasound examinations, no additional instances of CCHD were detected by fetal echocardiography. No unanticipated instances of CCHD were diagnosed postnatally.

CONCLUSIONS

With current American Heart Association screening guidelines, automatic fetal echocardiography in the setting of normal detailed anatomic ultrasound findings provided limited benefit in detecting congenital heart defects that would warrant immediate postnatal interventions. More selective use of automatic fetal echocardiography in at-risk pregnancies should be explored.

The added value of screening fetal echocardiography after normal cardiac views on a detailed ultrasound

OBJECTIVE

Evaluate fetal echocardiography's ability to detect critical (lesions requiring immediate neonatal intensive care) congenital heart disease (CHD) after normal anatomic cardiac views on detailed ultrasound.

METHODS

Singletons with both a detailed ultrasound at 18 + 0 to 22 + 6 weeks and echocardiogram performed at least 14 days later and at 20 + 0 to 24 + 6 weeks. Cases with cardiac pathology on detailed ultrasound were excluded. Different combinations of cardiac views were described: Basic (four-chamber, outflow tracts), Expanded (plus three-vessel view), and Complete (plus ductal/aortic arches). "Normal" was defined on either 2D gray scale or color Doppler. Primary outcome was rates of critical CHD missed on ultrasound but seen on fetal echocardiogram.

RESULTS

One thousand two hundred twenty-three women had normal Basic cardiac views. One thousand one hundred ninety (97.3%) were confirmed normal on echocardiogram. Twenty-one (1.71%) total CHDs were missed, and three were critical (0.25%; 95% CI, 0.03%-0.53%). Of the 1,223 women, 763 had Complete views. Ten (1.31%) total CHDs were missed and one (0.13%; 95% CI, 0.13%-0.36%) was confirmed critical.

CONCLUSION

Fetal echocardiography can increase CHD detection despite normal cardiac anatomy on detailed ultrasound; however, CHDs missed are rarely critical. Approximately 750 fetal echocardiograms need to be performed to detect one critical CHD with Complete normal cardiac views on detailed ultrasound.

Isolated Single Umbilical Artery and Fetal Echocardiography: A 25-Year Experience at a Tertiary Care City Hospital

OBJECTIVES

To review our 25-year experience with a single umbilical artery and fetal echocardiography to estimate the need for this test in cases of an isolated single umbilical artery.

METHODS

We conducted a retrospective review of 436 patients with a diagnosis of a single umbilical artery at our institution between 1990 and 2015. Two hundred eighty-eight women had both an anatomic survey and a fetal echocardiogram. Pregnancies with concurrent extracardiac anomalies or aneuploidy were excluded. The study population was divided into 3 groups based on cardiac views on the anatomic survey: normal, incomplete, and suspicious. Echocardiographic results were compared among the 3 groups. The primary outcome measure was the incidence of cardiac anomalies in the normal group at fetal echocardiography. The data were analyzed by the χ² test or Fisher exact test.

RESULTS

The mean maternal age ± SD of the group was 29.2 ± 6.2 years; 44.1% were primiparas. The mean gestational age at diagnosis was 22.6 ± 5.2 weeks, and the mean gestational age at fetal echocardiography was 25.1 ± 3.6 weeks. In the normal group, 99.1% (230 of 232) of women had a normal fetal echocardiogram; the 2 abnormal cases were ventricular septal defects. Normal echocardiograms were obtained in 81.8% (36 of 44) and 25.0% (3 of 12) of the "incomplete" and "suspicious" groups, respectively.

CONCLUSIONS

Fetuses with a single umbilical artery, in the absence of structural abnormalities, and with normal cardiac views at the time of the anatomic survey do not warrant an echocardiogram.

Is routine preoperative transthoracic echocardiography necessary in newborns with myelomeningocele?

OBJECTIVE

Congenital heart disease (CHD) is common in newborns with myelomeningocele. Echocardiography before neonatal back closure has been recommended. Its utility in the era of prenatal diagnosis is unclear.

STUDY DESIGN

We reviewed all newborns with myelomeningocele evaluated by preoperative echocardiography at our institution over 11 years.

RESULT

Seventy-six successive newborns were identified. Ninety-one percent were prenatally diagnosed with myelomeningocele. In all, 1% had critical, 12% critical or non-critical and 22% critical, non-critical or possible CHD. The single case of critical CHD was both prenatally diagnosed and clinically identifiable.

CONCLUSION

The prevalence of CHD in newborns with myelomeningocele is increased compared with the general population; however, critical disease is uncommon. We propose preoperative echocardiography is unnecessary when the myelomeningocele is prenatally diagnosed, antenatal cardiac screening is complete and normal, and the newborn is clinically well.

Cost-effectiveness of prenatal screening strategies for congenital heart disease

OBJECTIVE

The economic implications of strategies to improve prenatal screening for congenital heart disease (CHD) in low-risk mothers have not been explored. The aim was to perform a cost-effectiveness analysis of different screening methods.

METHODS

We constructed a decision analytic model of CHD prenatal screening strategies (four-chamber screen (4C), 4C + outflow, nuchal translucency (NT) or fetal echocardiography) populated with probabilities from the literature. The model included whether initial screens were interpreted by a maternal-fetal medicine (MFM) specialist and different referral strategies if they were read by a non-MFM specialist. The primary outcome was the incremental cost per defect detected. Costs were obtained from Medicare National Fee estimates. A probabilistic sensitivity analysis was undertaken on model variables commensurate with their degree of uncertainty.

RESULTS

In base-case analysis, 4C + outflow referred to an MFM specialist was the least costly strategy per defect detected. The 4C screen and the NT screen were dominated by other strategies (i.e. were more costly and less effective). Fetal echocardiography was the most effective, but most costly. On simulation of 10 000 low-risk pregnancies, 4C + outflow screen referred to an MFM specialist remained the least costly per defect detected. For an additional $580 per defect detected, referral to cardiology after a 4C + outflow was the most cost-effective for the majority of iterations, increasing CHD detection by 13 percentage points.

CONCLUSIONS

The addition of examination of the outflow tracts to second-trimester ultrasound increases detection of CHD in the most cost-effective manner. Strategies to improve outflow-tract imaging and to refer with the most efficiency may be the best way to improve detection at a population level.

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.