Perinatal outcome of fetal atrioventricular block: one-hundred-sixteen cases from a single institution

Development of a Z-score equation for atrioventricular interval measurement by two-dimensional pulsed Doppler echocardiography in normal fetuses between 16 and 33+6 weeks of gestation

PURPOSE

Fetal echocardiography is the primary diagnostic tool for assessing the atrioventricular (AV) time interval. Establishing a reference range for this parameter throughout pregnancy is essential for the early detection of potential abnormalities. The aim of this study was to develop a Z-score equation and establish specific percentiles for the AV time interval in normal fetuses between 16 and 33+6 weeks of gestation.

METHODS

A multicenter, prospective, cross-sectional study was conducted between 2018 and 2022. A large sample of pregnant women meeting specific eligibility criteria was included, while cases with potential confounders were excluded. Two-dimensional echocardiography with pulsed Doppler techniques was employed, focusing on the left ventricular inflow and outflow. Data were rigorously analyzed with careful assessment of measurements and normalization procedures.

RESULTS

In total, 1,309 echocardiograms were performed, and 1,183 pregnant women were included after applying the eligibility criteria. Detailed percentiles for each gestational age were determined, and a Z-score equation was formulated. A very weak correlation was observed between AV interval measurement and gestational age (r=0.16, P<0.001). In addition, the correlation between AV interval measurement and fetal heart rate was weak (r=-0.21, P<0.001). The Z-score for the AV interval measurement in milliseconds was derived as follows: Z-score=(AV interval measurement-111.3)/8.6.

CONCLUSION

This study provides a reference range and Z-score equation for the AV interval, which may enhance the accuracy of monitoring fetuses at risk for developing atrioventricular block-especially in pregnant women with specific antibodies-thus facilitating earlier diagnosis and treatment.

Isolated non-immune-mediated second-degree atrioventricular block in the fetus: natural history and predictive factors for spontaneous recovery

OBJECTIVES

To determine the clinical course of fetal isolated non-immune-mediated second-degree atrioventricular block (AVB) and the factors associated with spontaneous recovery in these cases.

METHODS

Fetuses with isolated non-immune-mediated second-degree AVB were recruited prospectively between 2014 and 2022. These fetuses were divided into two groups: those which recovered spontaneously and those which did not. Maternal and fetal characteristics and intrauterine and postnatal outcomes were compared between the two groups.

RESULTS

The study cohort included 20 fetuses with isolated non-immune-mediated second-degree AVB, diagnosed at a median gestational age of 22.0 (range, 17.0-35.0) weeks. In 12 fetuses, 1:1 atrioventricular conduction was restored spontaneously in utero and there was no recurrence during the postnatal follow-up period. In the remaining eight fetuses, second-degree AVB was maintained and, in six of these, the pregnancy was terminated on parental request. Of the two liveborn children who had persistent second-degree AVB prenatally, one had progressed to complete AVB at the latest follow-up, at the age of 34 months, but was asymptomatic, without heart enlargement or dysfunction. The other child progressed to complete AVB after delivery and was diagnosed with type-2 long QT syndrome. This infant died aged 2 months. Fetuses in the group that recovered spontaneously had earlier gestational age at diagnosis (median, 20.0 (range, 17.0-26.0) vs 24.5 (range, 18.0-35.0) weeks; P = 0.004) and higher atrial rate at diagnosis (median, 147 (range, 130-160) vs 138 (range, 125-149) bpm; P = 0.006) in comparison with the group that did not recover spontaneously. The best cut-off values for prediction of failure to recover spontaneously were 22.5 weeks' gestational age at diagnosis and 144 bpm atrial rate at diagnosis, with sensitivities of 87.5% and 75.0%, respectively, and specificities of 92.0% and 87.5%, respectively.

CONCLUSIONS

The outcome of 60% of fetuses with isolated non-immune-mediated second-degree AVB was favorable. Earlier gestational age and higher atrial rate at diagnosis were associated with spontaneous reversion to normal sinus rhythm. Prenatal genetic testing should be performed in cases with persistent AVB, to exclude heritable disorders including long QT syndrome. These findings provide important information for clinical management and prenatal counseling in these cases. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Monitoring of Women with Anti-Ro/SSA and Anti-La/SSB Antibodies in Germany-Status Quo and Intensified Monitoring Concepts

Background: The fetuses of pregnant women affected by anti-Ro/anti-La antibodies are at risk of developing complete atrioventricular heart block (CAVB) and other potentially life-threatening cardiac affections. CAVB can develop in less than 24 h. Treatment with anti-inflammatory drugs and immunoglobulins (IVIG) can restore the normal rhythm if applied in the transition period. Routine weekly echocardiography, as often recommended, will rarely detect emergent AVB. The surveillance of these pregnancies is controversial. Home-monitoring using a hand-held Doppler is a promising new approach. Methods: To obtain an overview of the current practice in Germany, we developed a web-based survey sent by the DEGUM (German Society of Ultrasound in Medicine) to ultrasound specialists. With the intention to evaluate practicability of home-monitoring, we instructed at-risk pregnant women to use a hand-held Doppler in the vulnerable period between 18 and 26 weeks at our university center. Results: There are trends but no clear consensus on surveillance, prophylaxis, and treatment of anti-Ro/La positive pregnant between specialists in Germany. Currently most experts do not offer home-monitoring but have a positive attitude towards its prospective use. Intensified fetal monitoring using a hand-held Doppler is feasible for pregnant women at risk and does not lead to frequent and unnecessary contact with the center. Conclusion: Evidence-based guidelines are needed to optimize the care of anti-Ro/La-positive pregnant women. Individual risk stratification could help pregnancy care of women at risk and is welcmed by most experts. Hand-held doppler monitoring is accepted by patients and prenatal medicine specialists as an option for intensified monitoring and can be included in an algorithm for surveillance.

Prenatal diagnosis of fetal bradyarrhythmia and postnatal outcome

INTRODUCTION

Prenatal diagnosis of Fetal bradyarrhythmia leads to parental and care provider anxiety as data on outcome is scarce. We aimed to correlate the prenatal presentation of fetal bradyarrhythmia with postnatal outcome.

METHODS

Retrospective analysis of case records from 2017 to 2021. All fetuses with sustained bradyarrhythmia beyond 11 weeks were included in the study.

RESULTS

Twenty fetuses were identified: mean gestational age at diagnosis was 23 weeks 2 days. The type of bradyarrhythmia was as follows: Complete atrioventricular block 10 (50 %), Sinus Bradycardia 7 (35 %), second degree atrioventricular block 2 (10 %), and Unclassified 1 (5 %). In 10 fetuses, cardiac and extracardiac anatomy were normal; 8 fetuses (40 %) had cardiac anomalies,1 fetus had intraventricular hemorrhage and 1 had nuchal cystic hygroma. Among the fetuses with associated anomalies, there were 5 terminations of pregnancy (TOP), 1 intrauterine fetal demise (IUD), 3 neonatal demise (NND) and 1 livebirth. Among fetuses with normal anatomy, there were 2 TOP and 8 livebirths; five of the 10 mothers (50 %) tested positive for Anti Ro/La antibodies. All the 6 liveborn fetuses with complete atrioventricular block are on conservative management: 2 on metaproterenol and 4 on clinical follow up. Nine out of the 10 cases that had a postnatal paediatric cardiology assessment had a correct prenatal diagnosis.

CONCLUSION

Correct prenatal identification of fetal bradyarrhythmia is feasible in about 90 % of cases. The risk of postnatal pacemaker requirement appears to be low irrespective of maternal Anti Ro/La status.

Congenital Heart Block

Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune disease and congenital heart defects are most commonly responsible. Recent genetic discoveries have highlighted our understanding of the underlying mechanism. Hydroxychloroquine shows promise in preventing autoimmune CCHB. Patients may develop symptomatic bradycardia and cardiomyopathy. The presence of these and other specific findings warrants placement of a permanent pacemaker to relieve symptoms and prevent catastrophic events. The mechanisms, natural history, evaluation, and treatment of patients with or at risk for CCHB are reviewed.

Fetal heart block: Vaginal delivery an option

BACKGROUND

Fetal heart block (FHB) occurs in approximately 1:20 000 births and is associated with significant morbidity and mortality. Vaginal delivery with intrapartum fetal scalp lactate monitoring is offered as an option at our centre for selected cases, in contrast with the published literature advocating caesarean birth.

AIMS

To review perinatal outcomes at delivery for FHB at a tertiary referral hospital.

MATERIALS AND METHODS

Ours was a retrospective cohort study from 1 January, 2007 to 30 June, 2020. The infant outcomes are summarised in three delivery groups: vaginal delivery, planned caesarean section (CS) and unplanned CS.

RESULTS

There were 23 newborns in the study period, with a median gestation at birth of 37.2 weeks and there was one antepartum fetal death in this cohort. Vaginal delivery was planned in 12 women: eight had normal births, three of these women progressed to an intrapartum (unplanned) CS and one woman had a planned CS. All live babies in the vaginal delivery cohort had an Apgar score greater than seven at five minutes. Of the 22 newborns, six required intubation, of which five had been delivered by a planned CS.

CONCLUSION

Our data suggest that planned vaginal delivery is a safe option for selected women carrying a fetus with FHB. Managing labour with serial fetal scalp lactates, and the involvement of senior clinicians are important factors in achieving a successful outcome.

Reversal of Fetal Heart Block in Antibody-Positive Mother After Hydroxychloroquine and Dexamethasone

Maternal autoantibody-related complete heart block in the fetus is considered irreversible. During prenatal care for a 25-year-old nulliparous Hispanic woman with newly diagnosed nephrotic-range proteinuria and positive anti-nuclear antigen antibody, complete fetal heart block with a ventricular rate of 60 beats per minute was detected on a fetal echocardiogram at 28-week gestation. A small pericardial effusion and ascites were noted consistent with fetal hydrops. Dexamethasone and hydroxychloroquine were initiated. Fetal rhythm improved to Mobitz type 1 second-degree heart block, with a ventricular rate of 91 beats per minute. The fetus was born prematurely at 34-week gestation with second-degree heart block which improved to first-degree heart block prior to hospital discharge. First-degree heart block persisted at 2 years of age with a P-R interval of 185 ms. Transplacental treatment with dexamethasone and hydroxychloroquine was associated with sustained reversal of complete heart block to sinus rhythm.

Outcome of Fetal Dysrhythmias with and without Extracardiac Anomalies

Fetal dysrhythmias are common abnormalities, which can be categorized into three types: rhythm irregularities, tachyarrhythmias, and bradyarrhythmias. Fetal arrhythmias, especially in high-risk pregnancies, require special monitoring and treatment. The aim of this study was to assess the stillbirth and early and late neonatal mortality rates for pregnancies complicated by fetal dysrhythmias from one single tertiary referral center from 2000 to 2022. Of the 1018 fetuses with congenital heart disease, 157 (15.42%) were evaluated in this analysis. Seventy-four (46.7%) fetuses had bradyarrhythmias, 51 (32.5%) tachyarrhythmias, and 32 (20.4%) had rhythm irregularities. Additional structural heart defects were detected in 40 (25.3%) fetuses and extracardiac anomalies in 29 (18.4%) fetuses. Thirteen (8.2%) families opted for termination of the pregnancy. Eleven (7.6%), out of 144 continued pregnancies ended in spontaneous intrauterine fetal death (IUFD). Neonatal death was observed in nine cases (5.7%), whereas three (1.9%) died within the first 7 days of life. Although most intrauterine fetal deaths occurred in pregnancies with fetal bradyarrhythmia, neonatal death was observed more often in fetuses with tachyarrhythmia (8.5%). The presence of extracardiac anomalies, congenital heart disease (CHD), and Ro-antibodies are predictive factors for the occurrence of IUFD. Rhythm irregularities without any other risk factor do not present higher risks of adverse perinatal outcome.

Outcome of Antibody-Mediated Fetal Heart Disease With Standardized Anti-Inflammatory Transplacental Treatment

Background Transplacental fetal treatment of immune-mediated fetal heart disease, including third-degree atrioventricular block (AVB III) and endocardial fibroelastosis, is controversial. Methods and Results To study the impact of routine transplacental fetal treatment, we reviewed 130 consecutive cases, including 108 with AVB III and 22 with other diagnoses (first-degree/second-degree atrioventricular block [n=10]; isolated endocardial fibroelastosis [n=9]; atrial bradycardia [n=3]). Dexamethasone was started at a median of 22.4 gestational weeks. Additional treatment for AVB III included the use of a β-agonist (n=47) and intravenous immune globulin (n=34). Fetal, neonatal, and 1-year survival rates with AVB III were 95%, 93%, and 89%, respectively. Variables present at diagnosis that were associated with perinatal death included an atrial rate <90 beats per minute (odds ratio [OR], 258.4; 95% CI, 11.5-5798.9; P<0.001), endocardial fibroelastosis (OR, 28.9; 95% CI, 1.6-521.7; P<0.001), fetal hydrops (OR, 25.5; 95% CI, 4.4-145.3; P<0.001), ventricular dysfunction (OR, 7.6; 95% CI, 1.5-39.4; P=0.03), and a ventricular rate <45 beats per minute (OR, 12.9; 95% CI, 1.75-95.8; P=0.034). At a median follow-up of 5.9 years, 85 of 100 neonatal survivors were paced, and 1 required a heart transplant for dilated cardiomyopathy. Cotreatment with intravenous immune globulin was used in 16 of 22 fetuses with diagnoses other than AVB III. Neonatal and 1-year survival rates of this cohort were 100% and 95%, respectively. At a median age of 3.1 years, 5 of 21 children were paced, and all had normal ventricular function. Conclusions Our findings reveal a low risk of perinatal mortality and postnatal cardiomyopathy in fetuses that received transplacental dexamethasone±other treatment from the time of a new diagnosis of immune-mediated heart disease.

Complete heart block in neonatal lupus: a forgotten cause of fetal bradycardia

The most common cause of congenital heart block (CHB) is neonatal lupus, an acquired autoimmune disease caused by transplacental transfer of maternal antibodies to the fetus. A full-term female neonate was admitted to neonatal intensive care unit for severe bradycardia with stable haemodynamics. The mother, showing no clinical symptoms or any particular history, was transferred to our tertiary centre for profound fetal bradycardia. At birth, the infant's ECG showed a third-degree atrioventricular block and echocardiography was normal. Cardiac neonatal lupus was confirmed with positive maternal anti-Ro antibodies. Under close monitoring, the infant tolerated the bradycardia well (median 67 beats per minute (bpm)) and was discharged on day 6 of life. There was no indication for pacemaker, but she would be on regular follow-up with a paediatric cardiologist. This article holds an important insight as it is the first confirmed case of autoimmune CHB in Cambodia in which the mother's antibody was found only after diagnosis on the neonate.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients: Developed in collaboration with and endorsed by the Heart Rhythm Society (HRS), the American College of Cardiology (ACC), the American Heart Association (AHA), and the Association for European Paediatric and Congenital Cardiology (AEPC) Endorsed by the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS)

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

Congenital Heart Block

Congenital complete heart block (CCHB) defines atrioventricular conduction abnormalities diagnosed in utero or within the first 27 days of life. Maternal autoimmune disease and congenital heart defects are most commonly responsible. Recent genetic discoveries have highlighted our understanding of the underlying mechanism. Hydroxychloroquine shows promise in preventing autoimmune CCHB. Patients may develop symptomatic bradycardia and cardiomyopathy. The presence of these and other specific findings warrants placement of a permanent pacemaker to relieve symptoms and prevent catastrophic events. The mechanisms, natural history, evaluation, and treatment of patients with or at risk for CCHB are reviewed.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consenus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology, (ACC) and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate follow-up in pediatric patients.

Prenatal Management Strategy for Immune-Associated Congenital Heart Block in Fetuses

Fetal congenital heart block (CHB) is the most commonly observed type of fetal bradycardia, and is potentially life-threatening. More than 50% of cases of bradycardia are associated with maternal autoimmunity, and these are collectively termed immune-associated bradycardia. Several methods have been used to achieve reliable prenatal diagnoses of CHB. Emerging data and opinions on pathogenesis, prenatal diagnosis, fetal intervention, and the prognosis of fetal immune-associated CHB provide clues for generating a practical protocol for clinical management. The prognosis of fetal immune-associated bradycardia is based on the severity of heart blocks. Morbidity and mortality can occur in severe cases, thus hieratical management is essential in such cases. In this review, we mainly focus on optimal strategies pertaining to autoimmune antibodies related to CHB, although the approaches for managing autoimmune-mediated CHB are still controversial, particularly with regard to whether fetuses benefit from transplacental medication administration. To date there is still no accessible clinical strategy for autoimmune-mediated CHB. This review first discusses integrated prenatal management strategies for the condition. It then provides some advice for clinicians involved in management of fetal cardiovascular disorder.

Current perspective and scope of fetal therapy: part 1

Fetal therapy term has been described for any therapeutic intervention either invasive or noninvasive for the purpose of correcting or treating any fetal malformation or condition. Fetal therapy is a rapidly evolving specialty and has gained pace in last two decades and now fetal intervention is being tried in many malformations with rate of success varying with the type of different fetal conditions. The advances in imaging techniques have allowed fetal medicine persons to make earlier and accurate diagnosis of numerous fetal anomalies. Still many fetal anomalies are managed postnatally because the fetal outcomes have not changed significantly with the use of fetal therapy and this approach avoids unnecessary maternal risk secondary to inutero intervention. The short-term maternal risk associated with fetal surgery includes preterm labor, premature rupture of membranes, uterine wall bleeding, chorioamniotic separation, placental abruption, chorioamnionitis, and anesthesia risk. Whereas, maternal long-term complications include risk of infertility, uterine rupture, and need for cesarean section in future pregnancies. The decision for invasive fetal therapy should be taken after discussion with parents about the various aspects like postnatal fetal outcome without fetal intervention, possible outcome if the fetal intervention is done, available postnatal intervention for the fetal condition, and possible short-term and long-term maternal complications. The center where fetal intervention is done should have facility of multi-disciplinary team to manage both maternal and fetal complications. The major issues in the development of fetal surgery include selection of patient for intervention, crafting effective fetal surgical skills, requirement of regular fetal and uterine monitoring, effective tocolysis, and minimizing fetal and maternal fetal risks. This review will cover the surgical or invasive aspect of fetal therapy with available evidence and will highlight the progress made in the management of fetal malformations in last two decades.

Neonatal lupus with left bundle branch block and cardiomyopathy: a case report

Background

Cardiac manifestations of neonatal lupus include an array of structural and conduction abnormalities due to placental transference of maternal anti-SSA/Ro and anti-SSB/La autoantibodies. Late-onset neonatal lupus cardiomyopathies, occurring outside the neonatal period, is an infrequently reported manifestation with unknown pathophysiology and poorly defined treatment regimens. Due to the rarity of this condition, additional studies and case reports are required to better understand and manage late-onset neonatal lupus cardiomyopathies.

Case presentation

A 4-week-old female, born to a mother with known anti-SSA/Ro and anti-SSB/La autoantibodies, presents with classic cutaneous manifestations for neonatal lupus and is found to have left bundle branch block, severely dilated cardiomyopathy with an ejection fraction of 25%, and a thin echogenic dyskinetic ventricular septum. Weekly second trimester and 30-week fetal echocardiograms showed no signs of structural or conduction abnormalities. There were no histologic signs of inflammation on cardiac tissue biopsy. After a complicated hospital course, she was successfully treated with biventricular pacemaker, intravenous immunoglobulin, and plasmapheresis.

Conclusions

We present a case of late-onset neonatal lupus with severe dilated cardiomyopathy, a dyskinetic ventricular septum, and left bundle branch block. To our knowledge, the dyskinetic ventricular septum has never been reported and left bundle branch block is rarely reported in NL. This case further validates the need for long term cardiac follow up for patients born with NL, even if lacking cardiac manifestations in the peripartum period. We characterize a unique presentation of a rare clinical entity, highlighting the diagnostic challenges, and describe a successful treatment course.

A Broader Perspective on Anti-Ro Antibodies and Their Fetal Consequences-A Case Report and Literature Review

The presence of maternal Anti-Ro/Anti-La antibodies causes a passively acquired autoimmunity that may be associated with serious fetal complications. The classic example is the autoimmune-mediated congenital heart block (CHB) which is due in most cases to the transplacental passage of Anti-Ro/Anti-La antibodies. The exact mechanisms through which these pathologic events arise are linked to disturbances in calcium channels function, impairment of calcium homeostasis and ultimately apoptosis, inflammation and fibrosis. CHB still represents a challenging diagnosis and a source of debate regarding the best management. As the third-degree block is usually irreversible, the best strategy is risk awareness and prevention. Although CHB is a rare occurrence, it affects one in 20,000 live births, with a high overall mortality rate (up to 20%, with 70% of in utero deaths). There is also concern over the lifelong consequences, as most babies need a pacemaker. This review aims to offer, apart from the data needed for a better understanding of the issue at hand, a broader perspective of the specialists directly involved in managing this pathology: the rheumatologist, the maternal-fetal specialist and the cardiologist. To better illustrate the theoretical facts presented, we also include a representative clinical case.

Prediction of outcome in fetal autoimmune complete heart block

Assessing cardiac function and risk stratification in a fetal anti-Sjögren syndrome type A (SSA) or anti-Sjögren syndrome type B (SSB) complete atrioventricular block (CAVB) is challenging. We aimed to evaluate the cardiovascular profile score (CVP) and its components in surveillance of fetuses with autoimmune CAVB.

METHODS

Retrospective cohort review of CAVB pregnancies, excluding fetuses with significant cardiac anomalies.

RESULTS

CAVBs are in 17 fetuses, diagnosed at mean gestational age of 23 ± 5 weeks. Overall mortality is 18%: 1 termination, 1 fetal demise (intrauterine fetal demise [IUFD]), and 1 postnatal death. Both mortalities had intrauterine growth restriction; IUFD had placental infarction. Presenting CVP 8.7 ± 1. No fetus had CVP <7; the score correlated with increased risk of perinatal death. The 2 mortalities had initial CVP scores of 8 and 9; both increased to 10 on subsequent exams. 30% of fetuses had low middle cerebral artery pulsatility (MCA-PI) on the last study. All had high umbilical artery pulsatility (UA-PI) throughout gestation. The 2 deaths had the lowest MCA-PI.

CONCLUSION

Despite low heart rates, high CVP scores in our cohort remained high and were not predictive of mortality. Abnormalities in MCA flow reflects fetal cerebral vasodilation that may indicate altered hemodynamics and be predictive of outcomes, but data is limited. Abnormal umbilical artery (UA) flow suggests that perinatal mortality may also be related to placental disease.

Routine repeated echocardiographic monitoring of fetuses exposed to maternal anti-SSA antibodies: time to question the dogma

In around 1% of exposed pregnancies, anti-Ro/SSA and anti-La/SSB antibodies lead to congenital heart block, the main feature of neonatal lupus syndrome. As such, echocardiographic screening to detect congenital heart block, done every other week from 16 weeks to at least 24 weeks gestation, is widely recommended for anti-SSA-positive pregnant women. Such screening is now routinely done in many centres worldwide. In this Viewpoint, we call this dogma into question for several reasons. Even if congenital heart block is discovered (which is rare), the usefulness of treatment with fluorinated steroids has not been shown, whereas the associated side-effects are well known. The discovery of congenital heart block very early in the pregnancy does not modify obstetric management, and at least 500 ultrasounds are needed to find one case of congenital heart block, which would ultimately be found by other means. Finally, this screening strategy misses most cases of congenital heart block because most affected women are not known to have anti-SSA antibodies, and thus are not screened. Accordingly, except in the context of research protocols, which are certainly needed and are outside the scope of this Viewpoint, overturning the dogma of routine repeated screenings for congenital heart block could save money and health-care staff time and prevent maternal stress without substantial clinical consequences.

Use of antenatal fluorinated corticosteroids in management of congenital heart block: Systematic review and meta-analysis

Objective

To evaluate outcomes of fluorinated corticosteroids, with or without other medications, for treatment of congenital heart block in-utero.

Study design

A search was conducted through MEDLINE, EMBASE, WEB OF SCIENCE and SCOPUS from inception to October 2017. Only comparative studies are considered eligible. Outcomes include fetal death, downgrade of heart block, neonatal death, need for neonatal pacing, fetal and maternal complications. Random effects model was used.

Results

Out of 923 articles, 12 studies were eligible. Compared to no treatment, there was no significant difference in incidence of fetal death (OR 1.10, 95%CI 0.65–1.84), neonatal death (OR 0.98, 95%CI 0.41–2.33), or need for pacing (OR 1.46, 95%CI 0.78–2.74). Heart block downgrade was significantly higher in treatment group (9.48%vs.1.76%, OR 3.27, 95%CI 1.23–8.71).

Conclusion

antenatal fluorinated corticosteroids do not improve fetal/neonatal morbidity or mortality of congenital heart block and are associated with higher incidence of fetal and maternal complications.

First Report of the Italian Registry on Immune-Mediated Congenital Heart Block (Lu.Ne Registry)

Objective: Neonatal Lupus (NL) is a rare syndrome caused by placental transfer of maternal anti-SSA/Ro and anti-La/SSB autoantibodies to the fetus. The rarity of this condition requires the establishment of multidisciplinary registries in order to improve our knowledge.

Method: Inclusion criteria in this retrospective study were the maternal confirmed positivity for anti-SSA/Ro and/or anti-SSB/La antibodies, and the presence of II or III degree congenital heart block (CHB) in utero or neonatal period (up to 27 days after birth).

Result: Eighty-nine cases of CHB were observed in 85 women with 88 pregnancies that occurred between 1969 and 2017. CHB was mostly detected in utero (84 cases, 94.2%), while five cases were observed in the neonatal period. A permanent pacemaker was implanted in 51 of 73 children born alive (69.8), whereas global mortality rate was 25.8% (23 cases): 16 in utero, five perinatal, and two during childhood. By univariate analysis, factors associated with fetal death were pleural effusion (p = 0.005, OR > 100; CI 95% 2.88->100 and hydrops (p = 0.003, OR = 14.09; CI 95% 2.01–122). Fluorinated steroids (FS) were administered in 71.4% pregnancies, and its use was not associated with better survival. Some centers treated all cases with fluorinated steroids and some centers did not treat any case. CHB was initially incomplete in 24 fetuses, and of them five cases of II degree block reverted to a lower degree block after treatments. Recurrence rate in subsequent pregnancies was 17.6% (3 out of 17). A prophylactic treatment was introduced in 10 of these 16 subsequent (58.8%) pregnancies, mostly with FS or high dose intravenous immunoglobulins.

Conclusion: This is the first report from the Italian Registry of neonatal lupus/CHB. The live birth rate was nearly 80%, with nearly two thirds of the children requiring the implantation of a pacemaker. The management of fetuses diagnosed with CHB was heterogeneous across Italian Centers. The registry at present is mainly rheumatological, but involvement of pediatric cardiologists and gynecologists is planned.

Fetal Arrhythmias: Genetic Background and Clinical Implications

Fetal arrhythmias are a common phenomenon of pregnancies. However, debates remain with regard to the etiologies and early treatment of choices for severe fetal arrhythmias. The gene regulatory networks govern cardiac conduction system development to produce distinct nodal and fast conduction phenotypes. The slow conduction properties of nodes that display automaticity are determined by the cardiac ion channel genes, whereas the fast conduction properties are regulated by the transcription factors. Mutations of genes specific for the developmental processes and/or functional status of cardiac conduction system including ion channel promoter (minK-lacZ), GATA family of zinc finger proteins (GATA4), the homeodomain transcription factor (Nkx2.5), the homeodomain-only protein (Hop) and the T-box transcription factors (Tbx2, Tbx3 and Tbx5), hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) and connexins, may cause fetal arrhythmias. It is expected that development of investigational antiarrhythmic agents based on genetic researches on cardiac conduction system, and clinical application of percutaneously implantable fetal pacemaker for the treatment of fetal arrhythmias would come to true.

In utero intervention for severe congenital heart disease

The aim of foetal cardiac therapy is to treat an abnormality at the developmental stage so that the process of cardiac growth, which is complex and relies on the volume and direction of circulating blood as well as genetic determinants, can continue. In reality, most cardiac interventions are palliative; hence, major abnormalities are still present at birth. Nevertheless, tangible benefits following successful foetal intervention include improved haemodynamics and reduction in secondary damage leading to better postnatal outcomes. In cases of semilunar valve stenosis, or atresia, foetal valvuloplasty aims to achieve a biventricular, rather than univentricular, circulation. Opening and stenting a restrictive atrial foramen may preserve the pulmonary function in cases of hypoplastic left heart syndrome, thereby increasing the chances of successful postnatal surgery. More recent endeavours include percutaneous implantation of a miniaturised pacemaker to treat complete heart block and the promotion of left-sided heart growth by chronic maternal hyperoxygenation. The true clinical benefit of these interventions over natural history remains uncertain because of the paucity of appropriate randomised controlled trials (RCTs). Foetal cardiac therapy must now move from a pioneering approach to one that is supported by evidence, as has been done successfully for other foetal therapies.

Fetal dysrhythmias

Fetal dysrhythmias are common abnormalities, usually manifesting as irregular rhythms. Although most irregularities are benign and caused by isolated atrial ectopics, in a few cases, rhythm irregularity may indicate partial atrioventricular block, which has different etiological and prognostic implications. We provide a flowchart for the initial management of irregular rhythm to help select cases requiring urgent specialist referral. Tachycardias and bradycardias are less frequent, can lead to hemodynamic compromise, and may require in utero therapy. Pharmacological treatment of tachycardia depends on the type (supraventricular tachycardia or atrial flutter) and presence of hydrops, with digoxin, flecainide, and sotalol being commonly used. An ongoing randomized trial may best inform about their efficacy. Bradycardia due to blocked bigeminy normally resolves spontaneously, but if it is due to established complete heart block, there is no effective treatment. Ongoing research suggests hydroxychloroquine may reduce the risk of autoimmune atrioventricular block. Sinus bradycardia (rate <3rd centile) may be a prenatal marker for long-QT syndrome.

Fetal arrhythmias: Surveillance and management

Fetal arrhythmias warrant sophisticated surveillance and management, especially for the high-risk pregnancies. Clinically, fetal arrhythmias can be categorized into 3 types: premature contractions, tachyarrhythmias, and bradyarrhythmias. Fetal arrhythmias include electrocardiography, cardiotocography, echocardiography and magnetocardiography. Oxygen saturation monitoring can be an effective way of fetal surveillance for congenital complete AV block or SVT during labor. Genetic surveillance of fetal arrhythmias may facilitate the understanding of the mechanisms of the arrhythmias and provide theoretical basis for diagnosis and treatment. For fetal benign arrhythmias, usually no treatment but a close follow-up is need, while persistant fetal arrhythmias with congestive heart dysfunction or hydrops fetalis, intrauterine or postnatal treatments are required. The prognoses of fetal arrhythmias depend on the type and severity of fetal arrhythmias and the associated fetal conditions. Responses of fetal arrhythmias to individual treatments and clinical schemes are heterogeneous, and the prognoses are poor particularly under such circumstances.

An evidence-based approach to pre-pregnancy counselling for patients with systemic lupus erythematosus

Patients with SLE are often young females of childbearing age and a pregnancy wish in this patient group is common. However, SLE patients are at high risk for adverse pregnancy outcomes that require adequate guidance. It is widely acknowledged that pre-pregnancy counselling is the pivotal first step in the management of SLE patients with a wish to become pregnant. Next, management of these patients is usually multidisciplinary and often requires specific expertise from the different physicians involved. Very recently a EULAR recommendation was published emphasizing the need for adequate preconception counselling and risk stratification. Therefore the present review specifically addresses the issue of pre-pregnancy counselling for SLE patients with an evidence-based approach. The review summarizes data retrieved from recently published, high-quality cohort studies that have contributed to a better understanding and estimation of pregnancy-related risks for SLE patients. The present review categorizes risks from a patient-oriented point of view, that is, the influence of pregnancy on SLE, of SLE on pregnancy, of SLE on the foetus/neonate and of SLE-related medication. Lastly, pre-pregnancy counselling of SLE patients with additional secondary APS is reviewed. Collectively these data can guide clinicians to formulate appropriate preventive strategies and patient-tailored monitoring plans during pre-pregnancy counselling of SLE patients.

Resolution of fetal second-degree atrioventricular block

Fetal atrioventricular (AV) block is a rare and potentially devastating condition. Most commonly fetal AV block is mediated by maternal lupus antibodies which cause irreversible damage to the AV node. For many fetuses, the only potential intervention is premature delivery and highly invasive pacemaker implantation. However, there exists a small subset of fetuses with non-immune mediated AV block who appear to have far better outcomes, with potential for spontaneous resolution and a return to sinus rhythm. Despite this, it is not clear that prenatal counseling takes this fact into account. We describe a series of three patients with non-immune fetal second-degree AV block with spontaneous resolution prior to delivery, underscoring the need for appropriate prenatal counseling in this scenario.

The prevention, screening and treatment of congenital heart block from neonatal lupus: a survey of provider practices

Objective

To survey an international sample of providers to determine their current practices for the prevention, screening, and treatment of congenital heart block (CHB) due to maternal Ro/SSA antibodies.

Methods

A survey was designed by the organizing committee of the 9th International Conference of Reproduction, Pregnancy and Rheumatic Diseases. It was sent to attendants of the conference and authors of recent publications or abstracts at ACR 2012, 2013 or 2014 on rheumatic diseases and pregnancy.

Results

In anti-Ro/SSA positive women, 80% of 49 respondents recommended screening by serial fetal echocardiogram (ECHO), with most starting at week 16 (59%) and stopping at week 28 (25%), although the time to stop varied widely. For women without a prior infant with neonatal lupus, respondents recommend every other week (44%) or weekly (28%) fetal ECHOs. For women with a prior infant with neonatal lupus, 80% recommend weekly fetal ECHOs. To prevent CHB, HCQ was recommended by 67% of respondents and most would start pre-pregnancy (62%). Respondents were asked about medications to treat varying degrees of CHB in a 20-week pregnant, anti-Ro and La positive SLE patient. For first degree, respondents recommended starting dexamethasone (53%) or HCQ (43%). For second degree, respondents recommended starting dexamethasone (88%). For third degree, respondents recommended starting dexamethasone (55%) or IVIg (33%), although 27% would not start treatment.

Conclusion

Despite the absence of official guidelines, many physicians with a focus on pregnancy and rheumatic disease have developed similar patterns in the screening, prevention and treatment of CHB.

Fetal cardiac arrhythmias: Current evidence

This article reviews important features for improving the diagnosis of fetal arrhythmias by ultrasound in prenatal cardiac screening and echocardiography. Transient fetal arrhythmias are more common than persistent fetal arrhythmias. However, persistent severe bradycardia and sustained tachycardia may cause fetal hydrops, preterm delivery, and higher perinatal morbidity and mortality. Hence, the diagnosis of these arrhythmias during the routine obstetric ultrasound, before the progression to hydrops, is crucial and represents a challenge that involves a team of specialists and subspecialists on fetal ultrasonography. The images in this review highlight normal cardiac rhythms as well as pathologic cases consistent with premature atrial and ventricular contractions, heart block, supraventricular tachycardia (VT), atrial flutter, and VT. In this review, the details of a variety of arrhythmias in fetuses were provided by M-mode and Doppler ultrasound/echocardiography with high-quality imaging, enhancing diagnostic accuracy. Moreover, an update on the intrauterine management and treatment of many arrhythmias is provided, focusing on improving outcomes to enable planned delivery and perinatal management.

Progress in the pathogenesis and treatment of cardiac manifestations of neonatal lupus

PURPOSE OF REVIEW

To provide new insights into pathogenesis, prevention and management of cardiac manifestations of neonatal lupus (cardiac neonatal lupus) and issues pertinent to all anti-SSA/Ro positive individuals of childbearing age.

RECENT FINDINGS

Antibody specificity with high risk for cardiac neonatal lupus remains elusive, but high titers of Ro60, Ro52 or Ro52p200 antibodies appear to be required. Varying antibody specificities to the p200 region of Ro52 can induce first-degree block in a rodent model. In consideration of the contribution of macrophages to inflammation and fibrosis in cardiac neonatal lupus, hydroxychloroquine (HCQ) is being considered as preventive therapy. Cord blood biomarkers support the association of fetal reactive inflammatory and fibrotic components with the development and morbidity of cardiac neonatal lupus. Data from U.S. and French registries do not provide evidence that the prompt use of fluorinated steroids in cases of isolated block significantly alters fetal/neonatal morbidity or mortality.

SUMMARY

The search for a high-risk cardiac neonatal lupus antibody profile remains, but high-titer antibodies to Ro60 and R052 are a consistent finding, and this may guide the need for fetal echocardiographic surveillance. The uniform use of fluorinated steroids to prevent progression of cardiac neonatal lupus or reduce mortality does not appear justified. HCQ, based on diminishing an inflammatory component of cardiac neonatal lupus, is under consideration as a potential preventive approach.

An unusual course of anti-Ro antibody-mediated fetal complete heart block

Fetal hydrops is a serious complication of immune-mediated congenital complete atrioventricular block. We present the case of a fetus with severe hydrops and profound bradycardia and an unusual favourable outcome. This case enhances the importance of considering the contribution of ventricular ectopic beats to the cardiac output when counselling and predicting outcome of complete heart block.

Hypoplastic Left Heart Syndrome with Congenital Complete Heart Block

Congenital complete atrioventricular block (CCAVB) is a rare condition with an incidence of 1 of 20,000 live births. Hypoplastic left heart syndrome (HLHS) occurs more frequently than CCAVB and occurs in 1 of 5000 live births. HLHS in association with CCAVB is exceedingly rare. In this report, we describe a rare case of HLHS and CCAVB diagnosed in utero. Postnatal diagnosis, management and outcome are presented as well as review of the medical literature.

Design and Testing of a Transcutaneous RF Recharging System for a Fetal Micropacemaker

We have developed a rechargeable fetal micropacemaker in order to treat severe fetal bradycardia with comorbid hydrops fetalis. The necessarily small form factor of the device, small patient population, and fetal anatomy put unique constraints on the design of the recharging system. To overcome these constraints, a custom high power field generator was built and the recharging process was controlled by utilizing pacing rate as a measure of battery state, a feature of the relaxation oscillator used to generate stimuli. The design and in vitro and in vivo verification of the recharging system is presented here, showing successful generation of recharging current in a fetal lamb model.

Emergency Pacing via the Umbilical Vein and Subsequent Permanent Pacemaker Implantation in a Neonate

A dying neonate with congenital complete atrioventricular block underwent an emergency temporary pacing via the umbilical vein 1 h after birth. Implantation of a permanent epicardial pacemaker system was performed at the age of 10 days. During the follow-up period of 3 months, the child had been growing well with the VVIR pacemaker.

Minimally invasive implantable fetal micropacemaker: mechanical testing and technical refinements

This paper discusses the technical and safety requirements for cardiac pacing of a human fetus with heart failure and hydrops fetalis secondary to complete heart block. Engineering strategies to meet specific technical requirements were integrated into a systematic design and implementation consisting of a novel fetal micropacemaker, a percutaneous implantation system, and a sterile package that enables device storage and recharging maintenance in a clinical setting. We further analyzed observed problems on myocardial fixation and pacing lead fatigue previously reported in earlier preclinical trials. This paper describes the technical refinements of the implantable fetal micropacemaker to overcome these challenges. The mechanical performance has been extensively tested to verify the improvement of reliability and safety margins of the implantation system.

Autoimmune congenital heart block: complex and unusual situations

Autoimmune congenital heart block (ACHB) is an immune-mediated cardiac disease included among the manifestations collectively referred to as neonatal lupus. The placental transference of maternal Ro/La autoantibodies may damage the conduction tissues during fetal development leading to blocking of signal conduction at the atrioventricular (AV) node in an otherwise structurally normal heart. Irreversible complete AV block is the main cardiac manifestation of ACHB, but some babies may develop endocardial fibroelastosis, valvular insufficiency, and/or frank cardiomyopathies with significantly reduced cardiac function requiring transplant. The severity of ACHB is illustrated by a global mortality rate of 20% and pacemaker rates of at least 64%, often within the first year of life. This review analyses the main complex and/or unusual clinical situations associated with ACHB, including unusual maternal immunological profiles, infrequent maternal autoimmune diseases, cardiac damage unrelated to AV block, fetal invasive management, late complications after birth, risk of congenital heart block (CHB) in ovodonation and in vitro fertilization techniques, the role of maternal features other than autoimmunity, the influence of the birth order or the risk of CHB in twins and triplets.

A novel method to estimate safety factor of capture by a fetal micropacemaker

We have developed a rechargeable fetal micropacemaker in order to treat severe fetal bradycardia with comorbid hydrops fetalis, a life-threatening condition in pre-term non-viable fetuses for which there are no effective treatment options. The small size and minimally invasive form factor of our design limit the volume available for circuitry and a power source. The device employs a fixed-rate and fixed-amplitude relaxation oscillator and a tiny, rechargeable lithium ion power cell. For both research and clinical applications, it is valuable to monitor the electrode-myocardium interface in order to determine that adequate pacemaker output is being provided. This is typically accomplished by observing the minimal stimulus strength that achieves threshold for pacing capture. The output of our simple micropacemaker cannot be programmatically altered to determine this minimal capture threshold, but a safety factor can be inferred by determining the refractory period for ventricular capture at a given stimulus strength. This is done by measuring the minimal timing between naturally occurring QRS complexes and pacing stimuli that successfully generate a premature ventricular contraction. The method was tested in a pilot study in four fetal sheep and the data demonstrate that a relative measure of threshold is obtainable. This method provides valuable real-time information about the electrode-tissue interface.

Assessment of fluorinated steroids to avert progression and mortality in anti-SSA/Ro-associated cardiac injury limited to the fetal conduction system

OBJECTIVES

Extension of disease beyond the atrioventricular (AV) node is associated with increased mortality in cardiac neonatal lupus (NL). Treatment of isolated heart block with fluorinated steroids to prevent disease progression has been considered but published data are limited and discordant regarding efficacy. This study evaluated whether fluorinated steroids given to manage isolated advanced block prevented development of disease beyond the AV node and conferred a survival benefit.

METHODS

In this retrospective study of cases enrolled in the Research Registry for NL, inclusion was restricted to anti-SSA/Ro-exposed cases presenting with isolated advanced heart block in utero who either received fluorinated steroids within 1 week of detection (N=71) or no treatment (N=85). Outcomes evaluated were: development of endocardial fibroelastosis, dilated cardiomyopathy and/or hydrops fetalis; mortality and pacemaker implantation.

RESULTS

In Cox proportional hazards regression analyses, fluorinated steroids did not significantly prevent development of disease beyond the AV node (adjusted HR=0.90; 95% CI 0.43 to 1.85; p=0.77), reduce mortality (HR=1.63; 95% CI 0.43 to 6.14; p=0.47) or forestall/prevent pacemaker implantation (HR=0.87; 95% CI 0.57 to 1.33; p=0.53). No risk factors for development of disease beyond the AV node were identified.

CONCLUSIONS

These data do not provide evidence to support the use of fluorinated steroids to prevent disease progression or death in cases presenting with isolated heart block.

Fetal and Neonatal Arrhythmias

Cardiac arrhythmias are an important aspect of fetal and neonatal medicine. Premature complexes of atrial or ventricular origin are the main cause of an irregular heart rhythm. The finding is typically unrelated to an identifiable cause and no treatment is required. Tachyarrhythmia most commonly relates to supraventricular reentrant tachycardia, atrial flutter, and sinus tachycardia. Several antiarrhythmic agents are available for the perinatal treatment of tachyarrhythmias. Enduring bradycardia may result from sinus node dysfunction, complete heart block and nonconducted atrial bigeminy as the main arrhythmia mechanisms. The management and outcome of bradycardia depend on the underlying mechanism.