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.

Geoepidemiology and clinical characteristics of neonatal lupus erythematosus: a systematic literature review of individual patients’ data

Background/aim

 Neonatal lupus erythematosus (NLE) is an autoimmune syndrome caused by transplacental transmission of maternal autoantibodies, often with devastating consequences. The objective of this systematic literature review was to analyze the demographic data, geoepidemiology, clinical, and serological characteristics associated with NLE.

Materials and methods

 We performed a systematic literature search of the Pubmed database covering the period from 1976 to August 2015, using the MeSH terms “neonatal lupus” or “congenital heart block”. To be included in the study, articles of any type (original articles, case series, and case reports) had to report on infants with NLE on an individualized (i.e. patient-by-patient) basis. 

Results

A total of 198 studies were included in the review, reporting on a total of 755 NLE patients. The most frequently reported clinical manifestations of NLE were congenital heart block (CHB, 65.2%), cutaneous lupus (33.1%), and cytopenias (15.5%). We found differences in NLE characteristics based on study geographical origin, with CHB being much more frequent in patients of European or American descent (49.4% and 35%, respectively), while reports originating from Asia reported a higher prevalence of skin involvement (45.2%). Most CHB cases (72.9%) were diagnosed between the 18th and 26th week of gestation.

Conclusions

 Phenotypic differences of NLE depending on race and country may reflect true pathophysiologic differences or methodologic discrepancies. While maternal autoimmune disease is not a prerequisite for the development of NLE, the existence of a truly “immunonegative” CHB is questionable. 

Echocardiographic assessment of ventricular contraction and synchrony in children with isolated complete atrioventricular block and epicardial pacing: Implications of interventricular mechanical delay

AIMS

To assess the correlations between interventricular mechanical delay (IVMD) and cardiac function in children with isolated complete atrioventricular block and epicardial pacing.

METHODS AND RESULTS

We enrolled 13 children (six boys) with an epicardial dual-chamber pacemaker due to isolated complete or advanced atrioventricular block. The patients were 9.8 (range, 6.8-15.3) years old, and none had symptomatic heart failure at the follow-up visit. Ventricular pacing sites, which remained the same for 7.2 (1.6-12.3) years, were the left ventricle (LV) in two patients, right ventricle (RV) in four patients, and both ventricles in seven patients. IVMD was ≤40 ms in six patients (short IVMD group) and >40 ms in seven patients (long IVMD group). Compared with the long IVMD group, the short IVMD group was associated with better LV longitudinal strain (-20% [-24% to -18%] vs -16% [-20% to -13%], P < .05). The short IVMD group had superior LV mechanical synchrony than the long IVMD group (septal to lateral delay of the time to peak longitudinal strain 15 [-16-78] ms vs 78 [13-93] ms, P < .05; standard deviation of the time to peak radial strain 13 [9-34] ms vs 35 [18-64] ms, P < .05).

CONCLUSION

In children with epicardial pacing at LV, RV, or both ventricles, a left-sided contraction delay was associated with poorer LV contraction and impaired LV synchrony. IVMD will help to stratify patients during follow-up.

Treatment of Congenital Complete Atrioventricular Heart Block With Permanent Epicardial Pacemaker in Neonatal Lupus Syndrome

Introduction:

Neonatal lupus syndrome (NLS) is a passively acquired autoimmune condition due to the transplacental passage of maternal anti-Ro/SSA and anti-La/SSB antibodies in mothers with systemic lupus erythematosus (SLE), and congenital complete heart block (CHB) is its most serious manifestation. Skin and hepatic involvement may occur in later infancy.

Case Presentation:

A term infant with fetal bradycardia, detected at the 23rd gestational age, was diagnosed with CHB due to NLS and was successfully treated with a permanent epicardial pacemaker. The patient was reported here due to rarity of the procedure in neonatal period.

Conclusions:

Mothers with SLE should be screened and closely followed up during pregnancy for the development of fetal atrioventricular (AV) block.

Heart Failure Summit Review: cardiac re-synchronisation therapy in the failing heart

Extrapolating cardiac resynchronization therapy (CRT) to pediatric patients with heart failure has at times been difficult given the heterogeneity of pediatric cardiomyopathies, varying congenital heart disease (CHD) substrates, and the fact that most pediatric heart failure patients have right bundle branch block (RBBB) as opposed to LBBB. Yet, despite these limitations a number of multi-center retrospective studies in North America and Europe have identified some data to suggest that certain sub-populations tend to respond positively to CRT. In order to address some of the heterogeneity it is helpful to subdivide pediatric and young adult patients with CHD into four potential groups: (1) CRT for chronic RV pacing, (2) dilated cardiomyopathies, (3) pulmonary right ventricles, and (4) systemic right ventricles. The chronic RV paced group, especially long-standing RV apical pacing, with ventricular dyssynchrony has consistently shown to be the group that best responds to a proactive resynchronization course. CRT therapy in pulmonary right ventricles such as post-op tetralogy of Fallot have shown some promise and may be considered especially if there is evidence of concomitant left ventricular dysfunction with an electrical dyssynchrony. Patients with systemic right ventricles such as post-atrial baffle surgery or congenitally corrected transposition reportedly do well with CRT in the presence of both inter-ventricular and intra-ventricular dyssynchrony. There is little doubt that moving forward to best way to identify which pediatric patients with heart failure will respond to CRT, will require a collaborative effort between the electrophysiologist and the echocardiographer to identify appropriate candidates with electrical and mechanical dyssynchrony.

Characteristics and long-term outcome of non-immune isolated atrioventricular block diagnosed in utero or early childhood: a multicentre study

AIMS

The natural history of congenital or childhood non-immune, isolated atrioventricular (AV) block is poorly defined.

METHODS AND RESULTS

We retrospectively studied 141 children with isolated, non-immune AV block diagnosed in utero, or up to 15 years of age, at 13 French medical centres, between 1980 and 2009. Patients with structural heart disease or maternal antibodies were excluded. Atrioventricular block was asymptomatic in 119 (84.4%) and complete in 100 (70.9%) patients. There was progression to complete AV block in 29/41 (70.7%) patients with incomplete AV block over 2.8 ± 3.4 years (1-155 months), but all patients with incomplete AV block may not have been included in the study. Narrow QRS complex was present in 18 of 26 patients (69.2%) with congenital, and 106 of 115 (92.2%) with childhood AV block. Pacemakers were implanted in 112 children (79.4%), during the first year of life in 18 (16.1%) and before 10 years of age in 90 (80.4%). The mean interval between diagnosis of AV block and pacemaker implants was 2.6 ± 3.9 years (0-300 months). The pacing indication was prophylactic in 70 children (62.5%). During a mean follow-up of 11.6 ± 6.7 years (1-32 years), no patient died or developed dilated cardiomyopathy (DCM). The long-term follow-up was uncomplicated in 127 children (90.1%).

CONCLUSION

In this large multicentre study, the long-term outcome of congenital or childhood non-immune, isolated AV block was favourable, regardless of the patient's age at the time of diagnosis. No patient died or developed DCM, and pacemaker-related complications were few.

Noninvasive cardiac output determination for children by the inert gas-rebreathing method

Standard methods for determination of cardiac output (CO) are either invasive or technically demanding. Measurement of CO by the inert gas-rebreathing (IGR) method, applied successfully in adults, uses a low-concentration mixture of an inert and a blood-soluble gas, respectively. This study tested the feasibility of this method for determining CO during exercise for pediatric patients with complete congenital atrioventricular block (CCAVB) stimulated with a VVI pacemaker. In this study, 5 CCAVB patients (age 9.2-17.4 years) were compared with 10 healthy age-matched boys and girls. Testing was performed with the Innocor system. The patients were instructed to breathe the test gas from a closed system. Pulmonary blood flow was calculated according to the washout of the soluble gas component. During standardized treadmill testing, CO was determined at three defined levels. The CO measurements were successful for all the study participants. The patients reached a lower peak CO than the control subjects (5.9 l/min/m(2) vs 7.3 [boys] and 7.2 [girls]). The stroke volume increase under exercise also was reduced in the patients compared with the control subjects. The feasibility of the IGR method for exercise CO testing in children was documented. Application of the IGR method for children requires careful instruction of the patients and appears restricted to subjects older than 8 years. The method offers new insights into mechanisms of cardiovascular adaptation in children with congenital heart disease.

Ultrasonographic diagnosis of delayed atrioventricular conduction during fetal life: a reliability study

OBJECTIVE

The objective of the study was to evaluate the reliability of the 2 most commonly used ultrasonographic approaches for monitoring fetal atrioventricular conduction time (AVCT): (1) superior vena cava/ascending aorta (SVC/AA), and (2) left ventricular inflow/outflow tract (LVI/O) Doppler recordings.

STUDY DESIGN

Echographic studies from fetuses followed up for first-degree atrioventricular block (AVB-1) between 1998 and 2008 were reviewed. The ability to identify atrial contractions in the same fetuses by the SVC/AA and LVI/O approaches was analyzed.

RESULTS

Sixty-six studies of 13 fetuses with AVB-1 were available. Atrial contractions were visible in all SVC/AA studies. With the LVI/O approach, atrial contractions could not be identified in 26 studies (39%). AVCT delay was significantly greater in the nonidentifiable compared with the identifiable atrial contraction group (P < .001). Differences in heart rate and gestational age were not significant.

CONCLUSION

The LVI/O is unsuitable for prenatal screening of conduction system anomalies.

[Update on pediatric cardiology and congenital heart disease]

The fields of pediatric cardiology and congenital heart disease have experienced considerable progress in the last few years, with advances in new diagnostic and therapeutic techniques that can be applied at all stages of life from the fetus to the adult. This article reviews scientific publications in a number of areas that appeared between August 2007 and September 2008. In developed countries, congenital heart disease is becoming increasingly prevalent in nonpediatric patients, including pregnant women. Actions aimed at preventing coronary heart disease must be started early in infancy and should involve the promotion of a healthy diet and lifestyle. Recent developments in echocardiography include the introduction of three-dimensional echocardiography and of new techniques such as two-dimensional speckle tracking imaging, which can be used for both anatomical and functional investigations in patients with complex heart disease, including a univentricular heart. Progress has also occurred in fetal cardiology, with new data on prognosis and prognostic factors and developments in intrauterine interventions, though indications for these interventions have still to be established. Heart transplantation has become a routine procedure, supplemented in some cases by circulatory support devices. In catheter interventions, new devices have become available for the closure of atrial or ventricular septal defects and patent ductus arteriosus as well as for percutaneous pulmonary valve implantation. Surgery is also advancing, in some cases with hybrid techniques, particularly for the treatment of hypoplastic left heart syndrome. The article ends with a review of publications on cardiomyopathy, myocarditis and the treatment of bacterial endocarditis.

Outcome of prenatally diagnosed isolated congenital complete atrioventricular block treated with transplacental betamethasone or ritodrine therapy

The effectiveness of transplacental drug therapy for prenatally diagnosed isolated congenital complete atrioventricular block (CCAVB) is controversial. Nine cases of prenatal isolated CCAVB were treated from 2002 to 2007. Ritodrine was administered transplacentally to all fetuses and betamethasone to those whose mothers tested positive for maternal anti-SSA/Ro antibodies. Six of the nine patients had an anti-SSA/Ro-positive mother and received transplacental betamethasone 4 mg/day at a median gestational age of 28 weeks (range, 24-31 weeks). No patients exhibited an improvement in the degrees of complete heart block, and one patient died in utero. No serious adverse events occurred. After the mean follow-up period of 1.7 +/- 1.3 years, all five patients treated with transplacental betamethasone experienced a good cardiac function, whereas one of the three patients not treated with transplacental betamethasone experienced cardiomyopathy and died at the age of 4 months. Pacemaker implantation was required for seven of the eight live-born infants. Transplacental betamethasone therapy for the patients with isolated CCAVB neither improved the degree of atrioventricular block nor decreased the rate of patients requiring pacemaker implantation, but it probably reduced the risk for the development of myocardial disease.