Outcome of high-risk neonates with congenital complete heart block paced in the first 24 hours after birth

Epicardial pacing lead implantation for congenital complete atrioventricular block immediately after birth: a case report

BACKGROUND

The incidence of congenital complete atrioventricular block is estimated to be 1 per 20,000 deliveries. In the fetal period, the fetal mortality rate is high, but the treatment strategy has not yet been established. In severe cases, early postnatal pacing therapy is necessary.

CASE PRESENTATION

A 0-day-old Japanese baby girl was diagnosed with fetal congenital complete atrioventricular block during a prenatal physical examination. A joint conference was held preoperatively among multidisciplinary departments, and a cesarean section was performed at 37 weeks pregnancy, immediately followed by scheduled internal ventricular pacing lead implantation in an adjacent room. Percutaneous pacing was ineffective. The epicardial pacing lead was sutured at 17.5 minutes after birth, and perioperative management was successful with a heart rate and pulse rate of 150 beats per minute.

CONCLUSION

The infant with a congenital complete atrioventricular block was rescued by an uneventful epicardial lead implantation.

Emergency pacing via the umbilical vein of a neonate with congenital complete atrioventricular block: a report of two cases

We report two cases of successful emergency pacing via the umbilical vein in neonates with congenital complete atrioventricular block. The first patient, a neonate with normal cardiac anatomy, underwent emergency temporary pacing via the umbilical vein under echocardiographic guidance. The patient underwent permanent pacemaker implantation on postnatal day 4. The second patient, a neonate with heterotaxy syndrome, underwent emergency temporary pacing through the umbilical vein under fluoroscopic guidance. The patient underwent permanent pacemaker implantation on postnatal day 17.

Pacemaker Management and In-Hospital Outcomes in Neonatal Congenital Atrioventricular Block

BACKGROUND

Neonatal congenital atrioventricular block (nCAVB) is rare, causes bradycardia, confers high mortality, and frequently requires pacing. In-hospital outcomes and pacemaker management in nCAVB are limited.

OBJECTIVES

The purpose of this study was to analyze pacing and outcomes of nCAVB with and without congenital heart disease (CHD) using a multicenter database.

METHODS

A Pediatric Health Information System database review from January 1, 2004, to June 30, 2022. Patients <31 days of age with a nCAVB International Classification of Diseases-9th/10th Revision diagnosis code and no cardiac surgeries except pacemaker were included. Pacing and in-hospital mortality were analyzed using univariate and multivariable logistic statistics and competing risk and event-free survival models.

RESULTS

Of 1,146 patients with nCAVB, 659 (57.5%) were girls and 506 (44.2%) were premature. Among the 326 (28.4%) with CHD, 134 (41.1%) underwent pacemaker insertion as initial intervention and 56 (17.2%) had temporary pacing wires. In-hospital mortality occurred in 118 (36.2%), with increased adjusted odds with temporary pacing wires placed at 0 to 1 or 2 to 7 days of age relative to no wires, and with decreased odds among pacemakers placed at 2 to 7 or 8+ days of age relative to no pacemaker. Of 820 (71.6%) without CHD, 334 (40.7%) underwent pacemaker insertion as the initial intervention and 81 (9.9%) had temporary pacing wires. In-hospital mortality occurred in 69 (8.4%) with increased adjusted odds in prematurity and decreased odds among pacemaker placement at 2 to 7 days of age relative to no pacemaker.

CONCLUSIONS

Over 18.5 years, in-hospital mortality occurred in 36.2% of nCAVB patients with CHD and 8.4% with non-CHD. Associations with increased in-hospital mortality included CHD and prematurity and decreased with pacemaker placement. Prospective registries are needed to better characterize and standardize management of this rare but high-mortality disease.

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.

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.

Care of the Fetus With Congenital Cardiovascular Disease: From Diagnosis to Delivery

BACKGROUND

The majority of congenital cardiovascular disease including structural cardiac defects, abnormalities in cardiac function, and rhythm disturbances can be identified prenatally using screening obstetrical ultrasound with referral for fetal echocardiogram when indicated.

METHODS

Diagnosis of congenital heart disease in the fetus should prompt assessment for extracardiac abnormalities and associated genetic abnormalities once maternal consent is obtained. Pediatric cardiologists, in conjunction with maternal-fetal medicine, neonatology, and cardiothoracic surgery subspecialists, should counsel families about the details of the congenital heart defect as well as prenatal and postnatal management.

RESULTS

Prenatal diagnosis often leads to increased maternal depression and anxiety; however, it decreases morbidity and mortality for many congenital heart defects by allowing clinicians the opportunity to optimize prenatal care and plan delivery based on the specific lesion. Changes in prenatal care can include more frequent assessments through the remainder of the pregnancy, maternal medication administration, or, in selected cases, in utero cardiac catheter intervention or surgical procedures to optimize postnatal outcomes. Delivery planning may include changing the location, timing or mode of delivery to ensure that the neonate is delivered in the most appropriate hospital setting with the required level of hospital staff for immediate postnatal stabilization.

CONCLUSIONS

Based on the specific congenital heart defect, prenatal echocardiogram assessment in late gestation can often aid in predicting the severity of postnatal instability and guide the medical or interventional level of care needed for immediate postnatal intervention to optimize the transition to postnatal circulation.

Outcomes in Congenital and Childhood Complete Atrioventricular Block: A Meta-analysis

BACKGROUND

The long-term outcomes of patients with congenital and childhood complete atrioventricular block (CCAVB/ CAVB) after pacemaker implantation are unclear.

METHODS

We performed a meta-analysis of all the studies of CCAVB. A systematic search of PubMed and CENTRAL databases from 1^st January 1967 to 31^st January 2020 was performed. The quality of studies included was critically appraised using the Newcastle-Ottawa scale, and outcome data were analyzed using the restricted maximum likelihood function.

RESULTS

Twenty-nine studies were eligible for analysis, with a total of 1553 patients. The all-cause-mortality was 5.7 % [95% CI: 2.5-9.9%], while PICM was seen in 3.8% [95% CI: 1.2-7.2]. Diagnosis at birth [effect size (ES)(95%CI): -2.23 (-0.36 to -0.10); p<0.001], presence of congenital heart disease ([ES(95%CI): -0.67 (0.41 to 0.93); p<0.001], younger age at pacemaker implantation ([ES(95%CI): -0.01 (-0.02 to -0.001); p=0.02], and duration of pacing [ES(95%CI): -0.03 (-0.05 to -0.003); p=0.03], were associated with an higher mortality on binominal logistic regression. None of the parameters were significant on multivariate analysis.

CONCLUSION

Pooled proportional mortality in patients with CCAVB and CAVB is 5.7% with an infrequent incidence of PICM (3.8%) in the paced patients with AVB suggesting that pacing in these patients is an effective management strategy with a low incidence of long-term side effects. Registry and randomized data can throw additional light regarding the natural history and appropriate management strategy in these patients. This article is protected by copyright. All rights reserved.

Cohort study of congenital complete heart block among preterm neonates: a single-center experience over a 15-year period

Congenital complete heart block (CCHB) is a very rare condition, with high risk of mortality. Prematurity is associated with immaturity of the cardiovascular system. Morbidity related to CCHB and prematurity has never been described. We describe a tertiary perinatal center experience over a 15-year period on CCHB management and complications in preterm infants. This is a single-center observational cohort study. All neonates admitted to neonatal intensive care unit with a diagnosis of isolated CCHB between January 2006 and January 2021 were identified. All preterm neonates (< 37 weeks) were compared with a control cohort of term neonates (≥ 37 weeks). Antenatal data, complications of prematurity, medical, and surgical management of CCHB were recorded. Twenty-four neonates with isolated CCHB (16 preterm and 8 term) were born during the study period, including 5 very preterm (< 32 weeks) and 11 preterm (32 to 37 weeks). All very preterm were born via emergency caesarian section without antenatal steroid administration. They had multiple severe morbidities including chronic lung disease, necrotizing enterocolitis, grades 3-4 intraventricular hemorrhage, cystic periventricular leukomalacia, and longer periods of mechanical and non-invasive ventilatory support than preterm. Thirteen out of sixteen preterm infants had permanent pacemakers inserted, compared to 1/8 for term newborns. All babies born before 35-week gestation were either paced or died.Conclusion: Premature neonates with CCHB have high risk of mortality and morbidity especially if undiagnosed and born by unnecessary emergency caesarian section without antenatal steroids. Prematurity below 35 weeks may be associated with death or pacemaker insertion. This supports better antenatal screening to avoid induced prematurity. What is Known: • Congenital complete heart block is a very rare condition associated with high morbidity and mortality. • Antenatal risk factors for poor outcome include fetal hydrops, low ventricular rate (HR <55 beats per minute), and congenital heart defect. What is New: • Infants born <32 weeks with CCHB had no antenatal steroid administration, and sustained high burden of morbidity (chronic lung disease, intraventricular hemorrhage, and cystic periventricular leukomalacia). • Birth <35 weeks is strongly associated with requiring pacing prior to discharge or death.

Arrhythmias in Pregnancy

Increasing maternal mortality and incidence of arrhythmias in pregnancy have been noted over the past 2 decades in the United States. Pregnancy is associated with a greater risk of arrhythmias, and patients with a history of arrhythmias are at significant risk of arrhythmia recurrence during pregnancy. The incidence of atrial fibrillation in pregnancy is rising. This review discusses the management of tachyarrhythmias and bradyarrhythmias in pregnancy, including management of cardiac arrest. Management of fetal arrhythmias are also reviewed. For patients without structural heart disease, β-blocker therapy, especially propranolol and metoprolol, and antiarrhythmic drugs, such as flecainide and sotalol, can be safely used to treat tachyarrhythmias. As a last resort, catheter ablation with minimal fluoroscopy can be performed. Device implantation can be safely performed with minimal fluoroscopy and under echocardiographic or ultrasound guidance in patients with clear indications for devices during pregnancy. Because of rising maternal mortality in the United States, which is partly driven by increasing maternal age and comorbidities, a multidisciplinary and/or integrative approach to arrhythmia management from the prepartum to the postpartum period is needed.

Epicardial pacemaker insertion in a preterm very low birth weight neonate – An anaesthetic challenge

Congenital complete heart block (CCHB) has an incidence of one in 20,000 live births and carries a 20% risk of mortality. The hemodynamic instability due to bradycardia and asystole due to the increasing metabolic demands can be avoided by appropriate antenatal planning, timely delivery and initiation of medical treatment and early pacemaker insertion. In this report, we discuss the anaesthetic challenges of permanent epicardial pacemaker insertion with good outcomes in a 32-week gestational age 1380 grams neonate within a few hours of birth.

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.

Fetal Congenital Heart Block Associated With Maternal Primary Systemic Lupus Erythematosus and Sjogren's Syndrome

Congenital heart block is a grave condition reported in 0.5% of 100 live births. Systemic lupus erythematosus (SLE) and Sjogren's syndrome (SS) are chronic autoimmune and inflammatory condition, which affects multiple systems. The association of SLE and SS with pregnancy has been seen in the past. Usually, it shows anti-Ro/SSA and anti-Ro/SSB auto-antibodies in maternal serum, which is proportional to fetal Outcome. In this report, we present a case of a 29-year-old female gravida 4, para one and aborta 3, with a history of polycystic ovarian disease and multiple abortions. At 20 weeks of gestation, her antenatal examination revealed fetal bradycardia and heart block, which further led to SLE and SS diagnosis in her. She was treated with steroids to prevent further fetal complications. The patient delivered a healthy neonate at 38 weeks of gestation. The neonate eventually received a cardiac pacemaker and is now on regular follow-up.

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.

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.

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.

Epicardial Pacemaker in Neonates and Infants: Is There a Relationship Between Patient Size, Device Size, and Wound Complicatıon?

We aimed to investigate the complications after epicardial pacemaker (PM) implantation in neonates and infants and their relationship with factors such as device size and patient size. Between May 2010 and July 2018, 55 patients under 1 year of age who underwent epicardial PM placement were retrospectively evaluated. PM-related complications requiring rehospitalization were determined as wound site problems requiring surgical intervention, battery pocket infection, battery pocket dehiscence without infection, PM removal, relocation of the PM system, and replacement of the PM system with another system. The patients were divided into three groups: < 3 kg, 3-5 kg and > 5 kg. Fifty-five patients underwent PM implantation, 43 (78.2%) because of postoperative atrioventricular block (AVB), 10 (18.2%) because of congenital AVB, and two (3.6%) with diagnoses of c-TGA and AVB. Five (9%) patients incurred 18 complications. No statistically significant difference was observed in complication development between the groups (p > 0.05). Single- or dual-chamber device implantation did not affect complication development (p > 0.05). Despite the role of factors such as low weight, low age, and device volume in the development of wound complications, the relationship between these factors and complications is not statistically significant. Therefore, our results are encouraging in terms of the use of dual-chamber PMs instead of single-chamber ones in heart diseases in which AV synchronization is important.

Unconventional 2:1 Ventricular Pacing in a Neonate with Congenital Heart Block and Biventricular Noncompaction

Congenital complete heart block with concomitant biventricular noncompaction cardiomyopathy has been reported once previously. Although not universal, when restrictive physiology is present, impaired diastolic filling may pose a distinct challenge to pacing during the neonatal period. We present the case of a neonate with congenital complete heart block and biventricular noncompaction that resulted in severe diastolic dysfunction and atrioventricular dyssynchrony. We intentionally used 2:1 ventricular pacing to provide atrioventricular synchrony with every paced beat, and this resulted in hemodynamic and clinical improvement. This unconventional pacing technique may be beneficial in other neonates who have complete heart block and diastolic dysfunction.

Congenital heart block: Pace earlier (Childhood) than later (Adulthood)

Congenital complete heart block (CCHB) occurs in 2-5% of pregnancies with positive anti-Ro/SSA and/or anti-La/SSB antibodies, and has a recurrence rate of 12-25% in a subsequent pregnancy. After trans-placental passage, these autoantibodies attack and destroy the atrioventricular (AV) node in susceptible fetuses with the highest-risk period observed between 16 and 28 weeks' gestational age. Many mothers are asymptomatic carriers, while <1/3 have a preexisting diagnosis of a rheumatic disease. The mortality of CCHB is predominant in utero and in the first months of life, reaching 15-30%. The diagnosis of CCHB can be confirmed by fetal echocardiography before birth and by electrocardiography after birth. Whether early in-utero detection and treatment might prevent or reverse this condition remains controversial. In addition to autoantibody-associated CCHB, there is also an isolated (absent structural heart disease) nonimmune early- or late-onset heart block detected later in childhood that may be associated with specific genetic markers or other pathogenic mechanisms. In isolated immune or non-immune CCHB, cardiac pacemakers are implanted in symptomatic patients, however, data on the natural history of CCHB in the adult life indicate that all patients, even if asymptomatic, should receive a pacemaker when first diagnosed. However, important issues have emerged in these patients wherein life-long conventional right ventricular apical pacing may produce left ventricular dysfunction (pacing-induced cardiomyopathy) necessitating a priori alternate site pacing or subsequent upgrading to biventricular pacing. All these issues are herein reviewed and two algorithms are proposed for diagnosis and management of CCHB in the fetus and in the older individual.

Challenges in the diagnosis and management of isolated congenital complete atrioventricular block in premature newborns

Diagnostic and treatment challenges of congenital complete atrioventricular block in two premature newborn babies are presented. Timely recognition of this fetal condition, appropriate antenatal care, and treatment at a tertiary level care hospital as well as prompt postnatal management of the newborn baby are the key factors for good outcome. Prematurity is also associated with an additional risk of poor outcome and complications.

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.

Two case reports of neonatal autoantibody-associated congenital heart block

RATIONALE

Neonatal lupus erythematosus (NLE) is an infrequent disease caused by transplacental maternal autoantibodies. The most common effects of NLE include cutaneous involvement and congenital heart block (CHB), although it might involve multiple organs, such as the liver, lungs, blood, and nervous or digestive systems. Izmirly PM1 and Tonello et al recently reported cutaneous manifestations of neonatal lupus and risk of subsequent CHB. The most serious complication of NLE is complete atrioventricular (AV) block.

PATIENT CONCERNS

We experienced 2 cases of NLE that were diagnosed in the past year in our Neonatal Intensive Care Unit. These cases showed 2 different clinical spectrums (CHB, multisystemic effects). One case was a 32-week pregnant woman with combined liver damage and fever, and her fetus was premature due to bradycardia and pericardial effusion. The second case was a young pregnant woman who had systemic lupus erythematosus for 2 years and had been taking methylprednisolone and hydroxychloroquine for a long time since her illness. When prenatal testing at 28 weeks of pregnancy showed that the fetus had CHB, the mother began taking dexamethasone.

DIAGNOSIS

The first case was diagnosed as NLE with CHB after birth, while the second was diagnosed as NLE with CHB, ductus arteriosus, and atrial septal defect when she was born at 34 weeks.

INTERVENTIONS

Both of 2 cases were treated with steroids, intravenous immunoglobulin, and a diuretic. But the second case was treated with isoprenaline in addition to the above.

OUTCOMES

Both of the infants was followed up and found to be clinically normal. During the clinic follow-up of the first case, the 8-month-old infant was still asymptomatic with normal growth and development. Her heart rate fluctuated from 40 to 90 beats/minute.

LESSONS

Autoimmune CHB is a severe, potentially life-threatening disorder associated with passive transfer of maternal anti-Sjogren's syndrome A/Ro and anti-Sjogren's syndrome B/La autoantibodies. Mothers who are positive for these autoantibodies are recommended to have serial echocardiography and obstetric ultrasonography from the early second trimester. Newborns should be delivered at an early stage of gestation if there is evidence of pericardial effusion, ascites, increasing ventricular ectopy, reduced ventricular shortening fraction, or AV valve regurgitation. Aggressive medical management after birth should be coupled with pacemaker implantation in infants who do not respond to medical therapies alone.

Perinatal Care of Infants with Congenital Birth Defects

Prenatal diagnosis has changed perinatal medicine dramatically, allowing for additional fetal monitoring, referral and counseling, delivery planning, the option of fetal intervention, and targeted postnatal management. Teams participating in the delivery room care of infants with known anomalies should be knowledgeable about specific needs and expectations but also ready for unexpected complications. A small number of neonates will need rapid access to postnatal interventions, such as surgery, but most can be stabilized with appropriate neonatal care. These targeted perinatal interventions have been shown to improve outcome in selected diagnoses.

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.

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.

Minimally Invasive Epicardial Pacemaker Implantation in Neonates with Congenital Heart Block

BACKGROUND

Few studies have characterized the surgical outcomes following epicardial pacemaker implantation in neonates with congenital complete atrioventricular block (CCAVB).

OBJECTIVE

This study sought to assess the long-term outcomes of a minimally invasive epicardial approach using a subxiphoid access for pacemaker implantation in neonates.

METHODS

Between July 2002 and February 2015, 16 consecutive neonates underwent epicardial pacemaker implantation due to CCAVB. Among these, 12 (75.0%) had congenital heart defects associated with CCAVB. The patients had a mean age of 4.7 ± 5.3 days and nine (56.3%) were female. Bipolar steroid-eluting epicardial leads were implanted in all patients through a minimally invasive subxiphoid approach and fixed on the diaphragmatic ventricular surface. The pulse generator was placed in an epigastric submuscular position.

RESULTS

All procedures were successful, with no perioperative complications or early deaths. Mean operating time was 90.2 ± 16.8 minutes. None of the patients displayed pacing or sensing dysfunction, and all parameters remained stable throughout the follow-up period of 4.1 ± 3.9 years. Three children underwent pulse generator replacement due to normal battery depletion at 4.0, 7.2, and 9.0 years of age without the need of ventricular lead replacement. There were two deaths at 12 and 325 days after pacemaker implantation due to bleeding from thrombolytic use and progressive refractory heart failure, respectively.

CONCLUSION

Epicardial pacemaker implantation through a subxiphoid approach in neonates with CCAVB is technically feasible and associated with excellent surgical outcomes and pacing lead longevity.

Fetal Situs, Isomerism, Heterotaxy Syndrome: Diagnostic Evaluation and Implication for Postnatal Management

OPINION STATEMENT

A hallmark of vertebrate anatomy is asymmetry of structures, especially internal organs, on the left and right side of the body. Heterotaxy syndrome is the combination of correct-sided, and incorrect-sided organs. The establishment of the left-right axis is an early event in vertebrate embryogenesis. Failure to establish this axis has numerous consequences for later development and can result in a wide range of potential defects. Congenital heart disease is among the more frequent and serious problems. Heterotaxy syndrome is diagnosed prenatally with increasing frequency due to improved screening practices. The key to proper management of fetal heterotaxy syndrome is reliable determination of left and right in the fetus, a thorough understanding of associated defects and comprehensive imaging.

Management of congenital complete heart block in a low-birth-weight infant

Pacemaker implantation in infants during the early postnatal period is difficult because of their small body size and susceptibility to infection. We describe the successful pacemaker implantation for complete heart block in an infant weighing 803 g.

A premature low-birth-weight infant with congenital complete atrioventricular block and myocarditis successfully treated by staged pacemaker implantation

Congenital complete atrioventricular block is a known lethal condition. Although antenatal diagnosis and the technical advances of pacemaker treatment have reduced its mortality, treatment of premature babies with significant myocardial damage remains a challenge. In this paper, we report the case of a premature low-birth-weight infant with congenital complete atrioventricular block and extremely low ventricular rate, fetal hydrops, and myocarditis who was successfully treated with staged permanent pacemaker implantation.

Complications and Risk Assessment of 25 Years in Pediatric Pacing

BACKGROUND

Children who require cardiac pacemaker implantation have presented a small patient sub-population since the breakthrough of this technology in the 1950s and 1960s. Their small bodies result in a technical challenge for the operating surgeon and put the patient at risk for a series of specific complications. Our study aims to analyze complications and to identify risk factors of endocardial and epicardial pacemaker systems in children.

METHODS

All pacemaker-related operations in pediatric patients up to the age of 18 years from 1985 through 2010 were retrospectively evaluated. Demographic data including age, height, and weight were recorded. Idiopathic and postoperative dysrhythmias were analyzed separately.

RESULTS

A total of 149 pacemaker operations were performed in 73 patients. Thirty-two patients did not have a previous cardiac operation. Indications for revision included box exchange, lead-related problems, pacemaker pocket complications, impaired left ventricular function, and pectoral muscle stimulation. Increased pacing thresholds occurred in 17.2% of the patients with epicardial leads compared with 2.9% in the endocardial group. Aside from threshold-related revision, lead problems are more common in the endocardial group (30.4% vs 17.2%). Venous thrombosis occurred in 13.7% of the patients (only endocardial), preferentially (25%) in the weight group less than 15 kg and in idiopathic patients (15.6% vs 10.5% with prior cardiac surgery).

CONCLUSIONS

Cardiac pacing is particularly challenging in the pediatric patient population facing a large number of reoperations during their lifetime. The lack of clear superiority of either epicardial or endocardial pacing systems requires an individual concept.

Absent Pulmonary Valve, Tricuspid Atresia, and Congenital Heart Block

We describe management of a patient with a prenatal diagnosis of absent pulmonary valve, tricuspid atresia, ventricular septal defect, and congenital heart block. Initial treatment consisted of temporary pacemaker implantation, and subsequent palliation included a central shunt during the neonatal period and placement of a permanent pacemaker. At seven months of age, a bidirectional Glenn anastomosis was performed. Cardiac catheterization revealed high cavopulmonary pressures and ventricular dysfunction precluding Fontan completion. Heart transplantation was performed at 3.75 years of age. The patient is alive and well 26 months posttransplantation.

Perinatal outcome in fetuses with heterotaxy syndrome and atrioventricular block or bradycardia

Congenital atrioventricular (AV) block is commonly associated with heterotaxy syndrome; together they have reportedly low survival rates (10-25%). However, information about perinatal outcome and predictors of non-survival after prenatal diagnosis of this association is scarce. Therefore, we studied fetuses with heterotaxy syndrome and bradycardia or AV-block diagnosed between 1995 and 2011, and analyzed pre and post-natal variables. The primary outcome was death and the secondary outcome was pacemaker placement. Of the 154 fetuses with heterotaxy syndrome, 91 had polysplenia syndrome, 22/91(24%) with bradycardia or AV-block. Thirteen (59%) patients had sinus bradycardia at diagnosis, 8 (36%) complete AV block, and 1 (5%) second-degree AV-block. Three patients elected for termination of pregnancy (3/22, 14%), 4 had spontaneous fetal demise (4/22, 18%), and 15 (15/22, 68%) were live-born. Of the fetuses with bradycardia/AV-block, 30% presented with hydrops, 20% had ventricular rates <55 beats/min, and 10% had cardiac dysfunction. Excluding termination of pregnancy, 15/19 fetuses (79%) survived to birth. Among the 15 live-born patients, 4 had bradycardia and 11 had AV-block. A further 3 patients died in infancy, all with AV-block who required pacemakers in the neonatal period. Thus, the 1-year survival rate, excluding termination of pregnancy, was 63% (12/19). Of the remaining 12 patients, 9 required pacemaker. Predictors of perinatal death included hydrops (p < 0.0001), ventricular dysfunction (p = 0.002), prematurity (p = 0.04), and low ventricular rates (p = 0.04). In conclusion, we found a higher survival rate (63%) than previously published in patients with heterotaxy syndrome and AV block or bradycardia diagnosed prenatally. Hydrops, cardiac dysfunction, prematurity and low ventricular rates were predictors of death.

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.

"Planned" permanent pacemaker implantation in one-day-old newborn after prenatal diagnosis of congenital complete atrioventricular heart block

We present a case of a severely ill newborn with congenital atrioventricular heart block (CAVB) diagnosed prenatally. The initial drug therapy just after birth was ineffective, the heart rhythm remained 54 beats per minute, and control echocardiographies showed forthcoming decrease of the left ventricular function with mitral insufficiency. A permanent pacing system with bipolar electrodes eluting two steroids (Medtronic Capsule, Medtronic Inc. Minneapolis, USA) and Medtronic ADAPTA^® pulse generator (Medtronic Inc, Minneapolis, USA) was implanted on the first day of life. The pace control as well as wound healing were uncomplicated, and the baby was discharged home without additional medication. The procedure of permanent pacemaker implantation on the first day of life was safe and effective, as a benefit from a successfully performed prenatal program in our cooperating institutions.

[Fetal bradycardia: a retrospective study in 9 Spanish centers]

OBJECTIVE

The aim of this study is to review the current management and outcomes of fetal bradycardia in 9 Spanish centers.

METHODS

Retrospective multicenter study: analysis of all fetuses with bradycardia diagnosed between January 2008 and September 2010. Underlying mechanisms of fetal bradyarrhythmias were studied with echocardiography.

RESULTS

A total of 37 cases were registered: 3 sinus bradycardia, 15 blocked atrial bigeminy, and 19 high grade atrioventricular blocks. Sinus bradycardia: 3 cases (100%) were associated with serious diseases. Blocked atrial bigeminy had an excellent outcome, except for one case with post-natal tachyarrhythmia. Of the atrioventricular blocks, 16% were related to congenital heart defects with isomerism, 63% related to the presence of maternal SSA/Ro antibodies, and 21% had unclear etiology. Overall mortality was 20% (37%, if terminations of pregnancy are taken into account). Risk factors for mortality were congenital heart disease, hydrops and/or ventricular dysfunction. Management strategies differed among centers. Steroids were administrated in 73% of immune-mediated atrioventricular blocks, including the only immune-mediated IInd grade block. More than half (58%) of atrioventricular blocks had a pacemaker implanted in a follow-up of 18 months.

CONCLUSIONS

Sustained fetal bradycardia requires a comprehensive study in all cases, including those with sinus bradycardia. Blocked atrial bigeminy has a good prognosis, but tachyarrhythmias may develop. Heart block has significant mortality and morbidity rates, and its management is still highly controversial.

Pregnancy With SLE and Fetal Congenital Heart Block: A Case Report

Autoimmune AV block is usually seen in association with autoimmune antibodies in mother that cross the placenta and damage the AV node of fetus. A 24-year-old primigravida, diagnosed to have SLE, at 25 weeks period of gestation found to have fetal bradycardia. Her ANA was moderately positive, SS-A (Ro) antibodies and SS-B (La) antibodies were positive. Fetal ECHO showed no structural defect but heart rate was 55 - 60 beats per minute. She was put on dexamethasone (4 mg/day). She was lost on follow up and presented at term in emergency with labor pains and fetal bradycardia, underwent a lower segment caesarean section. Baby underwent a temporary cardiac pacing within 10 hours of birth followed by permanent pacing on day 3 of birth. Baby is doing well on follow up. Neonates with isolated congenital heart block who are monitored antenatally and delivered in a planned fashion at an institution capable of early pacing can have favorable outcomes.

Surgical Placement of Permanent Epicardial Pacing Systems in Very Low-Birth Weight Premature Neonates: A Review of Data From the Pediatric Cardiac Care Consortium (PCCC)

Few studies have characterized the surgical outcomes following epicardial pacemaker placement in very low-birth weight infants with congenital complete heart block. This study was undertaken to review the surgical experience with this patient population based on data from a large multi-institutional registry.

METHODS

The Pediatric Cardiac Care Consortium (PCCC) multi-institutional database was retrospectively reviewed to identify premature, low-birth weight neonates that underwent surgical placement of an epicardial pacing system for heart block. We reviewed 179 patients with birth weights less than 1.5 kg that underwent a major operative procedure. Of these, 10 patients underwent surgical placement of an epicardial pacing system for heart block. Patients had heart block in otherwise structurally normal hearts (n = 6) or heart block associated with complex structural congenital cardiac anomalies (n = 4).

RESULTS

There were no deaths directly related to the surgical placement of the epicardial pacing system. There were no immediate complications with either lead or generator placement. One generator pocket was revised three months following placement. Survival to discharge was 60%. The four deaths occurred at a mean of 11 days (range 1-45 days) following the procedure.

CONCLUSIONS

Neonates born with prematurity and congenital heart block represent a challenging subset of patients with significant mortality. Generator pocket breakdown and infection have been considered barriers to optimal short- and long-term outcomes. Among cases in the PCCC, there were no deaths or major complications that could be attributed to permanent epicardial pacemaker placement. These data suggest that an aggressive surgical strategy may be justified.

Extracorporeal membrane oxygenation support for intractable primary arrhythmias and complete congenital heart block in newborns and infants: short-term and medium-term outcomes

OBJECTIVES

To describe the experience with extracorporeal membrane oxygenation support for intractable primary arrhythmias in newborns and infants.

DESIGN

Retrospective study.

SETTING

A tertiary care pediatric hospital.

PATIENTS

Patients younger than 1 yr supported with extracorporeal membrane oxygenation for primary cardiac arrhythmias were identified from the institutional extracorporeal membrane oxygenation registry.

INTERVENTIONS

Extracorporeal membrane oxygenation support.

MEASUREMENTS AND MAIN RESULTS

Clinical characteristics and outcomes were investigated for patients with primary cardiac arrhythmia supported with extracorporeal membrane oxygenation. Outcomes investigated were time from initiation of extracorporeal membrane oxygenation support to arrhythmia control, duration of extracorporeal membrane oxygenation support, and results of interventions performed while supported with extracorporeal membrane oxygenation. We summarized the independent categorical and continuous variables using frequencies, percentages, and medians and ranges, respectively. Extracorporeal membrane oxygenation support was used in nine patients for rescue therapy for primary tachyarrhythmia and bradycardia. The primary arrhythmias were: focal atrial tachycardia (n = 2); reentrant supraventricular tachycardia (n = 3); junctional ectopic tachycardia (n = 2); and congenital complete atrioventricular block (n = 2) patients. Seven patients presented with severe hemodynamic compromise, with six patients requiring extracorporeal cardiopulmonary resuscitation. All patients required extracorporeal membrane oxygenation within 24 hrs of initial presentation. Balloon atrial septostomy was performed in three patients and ablation was performed in two patients. Sinus rhythm was achieved in all reentrant supraventricular tachycardia and rate control was established in both patients with focal atrial tachycardia and in one patient with junctional ectopic tachycardia while using extracorporeal membrane oxygenation support. All patients survived to hospital discharge, and median follow-up for the cohort was 5 yrs. There was one late death; all survivors had good overall and neurologic outcomes.

CONCLUSIONS

The requirement of extracorporeal membrane oxygenation support in newborns and infants with intractable arrhythmia is rare. Extracorporeal membrane oxygenation support does potentially carry morbidity; however, to prevent arrhythmia-related mortality, extracorporeal membrane oxygenation support and/or extracorporeal cardiopulmonary resuscitation should be considered in the management of hemodynamically unstable primary arrhythmias as an emergent lifesaving procedure.

Surgical Management of the Neonate With Heterotaxy and Long-Term Outcomes of Heterotaxy

A review of the many challenges facing the neonate with heterotaxy has identified total anomalous pulmonary venous connection, atrioventricular valve abnormalities, pulmonary atresia, and arrhythmias including heart block as particular risk factors for the child who will pursue a single-ventricle pathway. Experience varies widely between different centers as to the percentage of patients who are suitable for biventricular repair, ranging from less than 20% to greater than 50%. Biventricular repair may only require simple baffling of anomalous systemic or pulmonary veins or may involve complex intraventricular baffle repair of double-outlet right ventricle with common atrioventricular valve. The long-term complications of heterotaxy include accelerated development of pulmonary arteriovenous malformations after the Kawashima procedure, high mortality and morbidity for the Fontan procedure (although improving results have been reported more recently), and the development of late arrhythmias. Extracardiac problems include a high risk of volvulus if malrotation is present, suggesting the need for an elective Ladd procedure. The presence of associated ciliary dyskinesia appears to be associated with an increased risk of postoperative morbidity, particularly ventilator dependence and other respiratory complications. The child with heterotaxy faces many challenges that are often underappreciated by both caregivers and families.

Fetal cardiac arrhythmia detection and in utero therapy

The human fetal heart develops arrhythmias and conduction disturbances in response to ischemia, inflammation, electrolyte disturbances, altered load states, structural defects, inherited genetic conditions, and many other causes. Yet sinus rhythm is present without altered rate or rhythm in some of the most serious electrophysiological diseases, which makes detection of diseases of the fetal conduction system challenging in the absence of magnetocardiographic or electrocardiographic recording techniques. Life-threatening changes in QRS or QT intervals can be completely unrecognized if heart rate is the only feature to be altered. For many fetal arrhythmias, echocardiography alone can assess important clinical parameters for diagnosis. Appropriate treatment of the fetus requires awareness of arrhythmia characteristics, mechanisms, and potential associations. Criteria to define fetal bradycardia specific to gestational age are now available and may allow detection of ion channelopathies, which are associated with fetal and neonatal bradycardia. Ectopic beats, once thought to be entirely benign, are now recognized to have important pathologic associations. Fetal tachyarrhythmias can now be defined precisely for mechanism-specific therapy and for subsequent monitoring of response. This article reviews the current and future diagnostic techniques and pharmacologic treatments for fetal arrhythmia.

Controversies in the therapy of isolated congenital complete heart block

Controversies in the therapy of congenital complete heart block are reviewed in terms of the timing of pacemaker implantation, the type and complications of pacing and its role in the presence of myocardial dysfunction. Drug treatment may be useful in selected cases in the presence of pleural effusions, ascites and hydrops of the fetus, but have no effect on complete heart block. Administration of fluorinated steroids in anti-Ro antibody-positive mothers with the aim of preventing complete heart block has given controversial results. Because of the variety of the clinical presentations, especially in regard to pacing therapy, it is mandatory to refer patients with congenital complete heart block to specialized centers with adequate resources and experienced personnel.

Intra-diaphragmatic pacemaker implantation in very low weight premature neonate

Implantation of a pacemaker (PM) in very low weight premature neonates can be a challenging procedure because of the actual dimension of generators. Ideal placement of the PM is still controversial. We describe a technique of intra-diaphragmatic PM implantation in a 1.3 kg neonate.

The role of fetal echocardiography in fetal intervention: a symbiotic relationship

In this review, the authors explore the role of noninvasive and invasive fetal interventions in fetal cardiovascular disease guided by observations at fetal echocardiography. They first review fetal cardiac lesions that may be ameliorated by fetal intervention and then review noncardiac fetal pathologic findings for which fetal echocardiography can provide important insight into the pathophysiology and aid in patient selection for and timing of intervention and postintervention surveillance.