Mitral valve dysplasia syndrome: A unique form of left-sided heart disease

Reference Ranges for Pulsed-Wave Doppler of the Fetal Cardiac Inflow and Outflow Tracts from 13 to 36 Weeks' Gestation

BACKGROUND

Doppler assessment of ventricular filling and outflow tract velocities is an integral part of fetal echocardiography, to assess diastolic function, systolic function, and outflow tract obstruction. There is a paucity of prospective data from a large sample of normal fetuses in the published literature. The authors report reference ranges for pulsed-wave Doppler flow of the mitral valve, tricuspid valve, aortic valve, and pulmonary valve, as well as heart rate, in a large number of fetuses prospectively examined at a single tertiary fetal cardiology center.

METHODS

The study population comprised 7,885 fetuses at 13 to 36 weeks' gestation with no detectable abnormalities from pregnancies resulting in normal live births. Prospective pulsed-wave Doppler blood flow measurements were taken of the mitral, tricuspid, aortic, and pulmonary valves. The fetal heart rate was recorded at the time of each assessment. Regression analysis, with polynomial terms to assess for linear and nonlinear contributors, was used to establish the relationship between each measurement and gestational age.

RESULTS

The measurement for each cardiac Doppler measurement was expressed as a Z score (difference between observed and expected values divided by the fitted SD corrected for gestational age) and percentile. Analysis included calculation of gestation-specific SDs. Regression equations are provided for the cardiac inflow and outflow tracts.

CONCLUSIONS

This study establishes reference ranges for fetal cardiac Doppler measurements and heart rate between 13 to 36 weeks' gestation that may be useful in clinical practice.

Toward Eliminating Perinatal Comfort Care for Prenatally Diagnosed Severe Congenital Heart Defects: A Vision

Over the past 40 years, the medical and surgical management of congenital heart disease has advanced considerably. However, substantial room for improvement remains for certain lesions that have high rates of morbidity and mortality. Although most congenital cardiac conditions are well tolerated during fetal development, certain abnormalities progress in severity over the course of gestation and impair the development of other organs, such as the lungs or airways. It follows that intervention during gestation could potentially slow or reverse elements of disease progression and improve prognosis for certain congenital heart defects. In this review, we detail specific congenital cardiac lesions that may benefit from fetal intervention, some of which already have documented improved outcomes with fetal interventions, and the state-of-the-science in each of these areas. This review includes the most relevant studies from a PubMed database search from 1970 to the present using key words such as fetal cardiac, fetal intervention, fetal surgery, and EXIT procedure. Fetal intervention in congenital cardiac surgery is an exciting frontier that promises further improvement in congenital heart disease outcomes. When fetuses who can benefit from fetal intervention are identified and appropriately referred to centers of excellence in this area, patient care will improve.

Procedural, pregnancy, and short-term outcomes after fetal aortic valvuloplasty

OBJECTIVES

We aimed to evaluate the effect of technical aspects of fetal aortic valvuloplasty (FAV) on procedural risks and pregnancy outcomes.

BACKGROUND

FAV is performed in cases of severe mid-gestation aortic stenosis with the goal of preventing hypoplastic left heart syndrome (HLHS).

METHODS

The International Fetal Cardiac Intervention Registry was queried for fetuses who underwent FAV from 2002 to 2018, excluding one high-volume center.

RESULTS

The 108 fetuses had an attempted cardiac puncture (mean gestational age [GA] 26.1 ± 3.3 weeks). 83.3% of attempted interventions were technically successful (increased forward flow/new aortic insufficiency). The interventional cannula was larger than 19 g in 70.4%. More than one cardiac puncture was performed in 25.0%. Intraprocedural complications occurred in 48.1%, including bradycardia (34.1%), pericardial (22.2%) or pleural effusion (2.7%) requiring drainage, and balloon rupture (5.6%). Death within 48 hr occurred in 16.7% of fetuses. Of the 81 patients born alive, 59 were discharged home, 34 of whom had biventricular circulation. More than one cardiac puncture was associated with higher complication rates (p < .001). Larger cannula size was associated with higher pericardial effusion rates (p = .044). On multivariate analysis, technical success (odds ratio [OR] = 10.9, 95% confidence interval [CI] = 2.2-53.5, p = .003) and later GA at intervention (OR = 1.5, 95% CI = 1.2-1.9, p = .002) were associated with increased odds of live birth.

CONCLUSIONS

FAV is an often successful but high-risk procedure. Multiple cardiac punctures are associated with increased complication and fetal mortality rates. Later GA at intervention and technical success were independently associated with increased odds of live birth. However, performing the procedure later in gestation may miss the window to prevent progression to HLHS.

Fetal Cardiac Intervention in Critical Aortic Stenosis with Severe Mitral Regurgitation, Severe Left Atrial Enlargement, and Restrictive Foramen Ovale

OBJECTIVE

To assess the intrauterine course and outcome of fetal cardiac intervention (FCI) in fetuses with critical aortic stenosis (CAS), severe mitral regurgitation (MR), severe left atrial dilatation (LAD), and restrictive foramen ovale (RFO) or intact atrial septum.

METHODS

All fetuses with a prenatal diagnosis of CAS, severe MR, severe LAD, and RFO were retrospectively collected in one tertiary center for fetal medicine over a period of 10 years. Video recordings, pre- and postnatal charts were reviewed for cardiac and extracardiac anomalies, intrauterine course, and postnatal outcome.

RESULTS

Nineteen fetuses with CAS, severe MR, severe LAD, and RFO were diagnosed in the study period. In 5 cases, FCI was not considered as the parents either opted for expectative management or for termination. In the remaining 14 fetuses, 21 FCI were performed: 14 balloon valvuloplasties, 2 atrioseptostomies, and 5 fetal atrial stent insertions. Seven of 14 fetuses (50%) had fetal hydrops, 5 of 14 fetuses (36%) presented with intact atrial septum. Procedure-related death occurred in 5 fetuses after aortic valvuloplasty or concomitant atrioseptostomy but in none after fetal atrial stenting. Due to progressive hydrops, two terminations of pregnancy were performed. Among the 7 live births, 3 died in the neonatal period. The remaining 4 received single ventricle palliation, 2 following fetal aortic valvuloplasty and 2 after fetal atrial stent insertion.

CONCLUSIONS

CAS with severe MR, severe LAD, and RFO has a high overall mortality even in cases undergoing intrauterine intervention. Parameters that accurately predict the intrauterine and postnatal outcome have yet to be defined.

Norwood Procedure With Left Ventricle Exclusion in Complex Single Ventricle Patients: A Novel Technique

Background:

Hypoplastic left heart disease and its variants complicated by severe semilunar and atrioventricular valve insufficiency are associated with a high mortality risk in utero and postnatally. Through the description of three cases, this report outlines the evolution of a successful strategy of morphological left ventricle isolation (ie, “left-sided Starnes”) in caring for this rare cohort of patients with hypoplastic left heart syndrome (HLHS).

Methods:

This study includes three patients: two patients prenatally diagnosed and one transferred from an outside hospital. All patients presented with complex univentricular heart disease with a nonfunctional left ventricle and severe left-sided atrioventricular and/or semilunar valve insufficiency.

Results:

Two patients were delivered with an operating room on standby due to the possibility of emergent surgery being necessary; however, all patients were able to be medically stabilized after birth. Patient 1 underwent successful left ventricle exclusion with a fenestrated polytetrafluoroethylene (PTFE) patch, despite severe mitral valve regurgitation. Patient 2 reinforced the efficacy of PTFE patch occlusion in addition to having aortic valve closure with a small washing jet. Patient 3’s clinical course was successfully predicted based on the previous patients and outlined for the family prenatally. All patients are currently growing well at home, awaiting Fontan with marked improvement in cardiac function.

Conclusion:

This rare cohort of patients with HLHS having severe left-sided atrioventricular and/or semilunar valve insufficiency appear to survive to birth and can be medically stabilized prior to semiurgent intervention. The Norwood procedure with left ventricle exclusion appears to be a successful strategy for these unique patients.

Ultrasound evaluation of fetal critical aortic stenosis using the left atrium area/cardiac area ratio and the Doppler patterns in the pulmonary veins

In fetal critical aortic stenosis (AS), a double reverse pattern in the pulmonary veins (PVs) is associated with a poor prognosis. We evaluated the hemodynamic changes using PV Doppler and the left atrium area/cardiac area (LA/CA) ratio in a fetus at 28 weeks of gestation with critical AS complicated with hydrops fetalis, polyhydramnios, and cardiac abnormality. A markedly enlarged LA and severe mitral regurgitation with critical AS were detected, with LA/CA ratio = 0.40 and double reverse pattern with forward/reverse velocity time integral ratio (FRVR) = 1.18 on PV Doppler. After amniotic reduction at 31 weeks, the LA/CA ratio decreased (0.24) and the FRVR in PV increased (7.11). Forward flow through the fetal aorta was seen spontaneously, and hydrops fetalis was relieved with LA volume reduction. A male neonate weighing 2171 g was delivered via cesarean section at 36 weeks with an Apgar score of 5 and 6 at 1 and 5 min, respectively. He required atrial septal opening and bilateral pulmonary artery banding after birth, followed by Norwood operation. The double reverse pattern in PVs might be reversible. The change in FRVR in PVs and LA/CA ratio would be helpful in understanding the hemodynamic change in fetal critical AS.

Prenatal therapy for fetal cardiac disorders

Fetal cardiac abnormalities are some of the commonest congenital disorders seen in prenatal life. They can be anatomical or functional and can develop de novo or as a consequence of either maternal or fetal disease. Untreated, morbidity and mortality rates are high for hypoplastic left heart disorders and for some fetal tachy and bradyarrhythmias. Optimum management strategies are often not clear because of the lack of knowledge about the precise natural history of some of these conditions. Prenatal therapy ranges from invasive fetal cardiac intervention to maternal administration of drugs for transplacental transfer to the fetus. This comprehensive review covers many fetal cardiac disorders and various prenatal therapeutic options that are available.

Foetal therapy: what works? Closed interatrial septum

Hypoplastic left-heart syndrome and critical aortic stenosis with severely restricted or intact foramen ovale are associated with high neonatal mortality and poor long-term outcome. Despite accurate foetal diagnosis and successful postnatal catheter-based and surgical intervention, the 1-month survival rate is about 33%. Changes in pulmonary vascular architecture resulting in pulmonary hypertension result in important long-term morbidity. Prenatal relief of left atrial and pulmonary hypertension may promote normal pulmonary vascular and parenchymal development and improve short- and long-term outcomes. Foetal atrial balloon septostomy, laser perforation, and stenting of the foetal interatrial septum are the current options for foetal therapy. This paper provides an overview of foetal diagnosis, selection of patients for foetal intervention, and interventional techniques, and also reviews the current status of foetal and postnatal outcomes after intrauterine intervention.

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.

Future Directions of Fetal Interventions in Congenital Heart Disease

Fetal interventions for congenital heart disease have become important treatment modalities in the past 10 to 15 years. The basic hypothesis has been that a prenatal intervention may remodel cardiac morphology and function to such an extent that it may favorably alter the in utero natural history, resulting in improved prenatal and postnatal outcomes, including an increased likelihood of achieving biventricular circulation. This review discusses the current indications, techniques, and outcomes of fetal cardiac interventions and provides a glimpse into the future with regard to technical improvements and newer treatment modalities, such as maternal oxygenation and in utero pacemaker implantation.

Successful immediate newborn ross-konno and mitral valve repair following fetal aortic valvuloplasty

Perinatal management of severe mitral regurgitation (MR) and aortic stenosis (AS) is difficult; mortality is high, and there are few reports of successful postnatal biventricular repairs. We report a patient with severe MR and AS, diagnosed prenatally, that underwent a fetal aortic valvuloplasty and a successful modified Ross-Konno procedure with concomitant mitral valve repair shortly after birth.