Ascending aortic dilation in patients with congenital complete heart block

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.

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.

Effect of dual-chamber pacemaker implantation on aortic dilatation in patients with congenital heart block

Ascending aortic dilatation (AoD) in patients with structurally normal hearts and congenital heart block (CHB) has been previously described. The cause and management of AoD are yet to be determined. The aim of this study was to test the hypothesis that AoD in children with CHB regresses after the implantation of cardiac dual-chamber pacemakers (PMs). The secondary hypothesis was an association between the presence of maternal antibodies (SS-A or SS-B) and the degree of aortic dilatation. Clinical data with echocardiographic correlates of patients with CHB followed at a single institution were retrospectively reviewed. Comparison of the target structures diameter was based on 3 different z-score equations, with AoD defined as a z score >2. Inclusion criteria were CHB diagnosis by 12-lead electrocardiography or Holter recording and benefit from a permanent dual-chamber PM. Excluded were patients with incomplete echocardiographic measurements, those with major structural heart defects, and those with syndromes or diseases known to be associated with AoD. There were 17 patients, diagnosed at a median age of 6 months (interquartile range 0 to 47.8). Maternal antibodies were positive in 6 patients and negative in 11. All patients underwent PM implantation at a median age of 4.5 years (interquartile range 1.4 to 7.9). AoD (z score >2.0 according to 3 different equations) was present in 35% to 59% of patients. There was a significant reduction of mean ascending aortic z score in patients with AoD from 4.66 to 3.67 (p = 0.06), from 4.82 to 2.95 (p = 0.002), and from 6.07 to 3.39 (p = 0.006) according to the various z-score equations. Most patients with positive serology had AoD, without reaching statistical significance. In conclusion, AoD is associated with CHB, more likely in infants exposed to maternal antibodies. AoD decreases after the implantation of a PM. This is probably related to the regularization of stroke volume.

Outcomes of fetal echocardiographic surveillance in anti-SSA exposed fetuses at a large fetal cardiology center

BACKGROUND

Echocardiography screening in anti-SSA antibody exposed fetuses is controversial.

OBJECTIVE

The aim of this study is to evaluate utility of fetal echocardiography in anti-SSA exposure.

METHODS

Echocardiograms performed over 9 years for maternal anti-SSA exposure were reviewed for atrioventricular (AV) block, cardiomyopathy, arrhythmias, effusion, valve abnormalities, or other abnormalities identified by the echocardiographer. Fetuses with AV block referred to our institution and subsequently found to be anti-SSA exposed were also identified.

RESULTS

Six hundred thirty six echocardiograms were performed on 140 fetuses (Cohort 1) of 134 women screened for maternal anti-SSA +/- anti-SSB antibodies. No fetuses developed second or third-degree AV block or cardiomyopathy (odds ratio 0.1, CI 0.0051 to 1.9410, p = 0.13). Dexamethasone was administered to three fetuses for sinus bradycardia, echogenicity near AV node, and ventricular systolic dysfunction with valve regurgitation; all normalized. Screening echocardiograms identified: sinus bradycardia (n = 1), PR prolongation (n = 5), premature atrial contractions (n = 3), valve regurgitation (n = 24), echogenic myocardium (n = 4), and pericardial effusion (n = 1). Isolated tricuspid regurgitation and first-degree AV block did not progress. Nine cases of SSA-mediated AV block (Cohort 2) were referred after heart block developed.

CONCLUSIONS

Serial fetal echocardiography in anti-SSA exposed fetuses did not detect AV block. In rare cases, dexamethasone treatment may have affected disease course.

Prenatal evaluation and management of fetuses exposed to Anti-SSA/Ro antibodies

Maternal anti-SSA antibodies are common, existing in up to 2 % of the general population. Fetuses exposed to these antibodies are at risk for both cardiac and noncardiac complications. The cardiac complications include arrhythmias, structural disease, and cardiomyopathy. Although rare, the cardiac disease associated with these antibodies is permanent and severe. Current fetal echocardiographic screening tools are nonspecific. The type and frequency of screening needed is controversial. Although promising transplacental treatment strategies exist, prospective randomized studies are lacking. Dexamethasone, the medication used most frequently, imposes significant risks to both mother and fetus. This report presents a discussion of the at-risk population, the spectrum of fetal cardiac disease associated with maternal anti-SSA antibodies, the current fetal echocardiographic screening tools, the therapeutic options, and the management and delivery planning strategies. With appropriate prenatal follow-up, assessment, and delivery planning, even high-risk fetuses can be delivered safely and managed effectively.

Relation of maternal anti-Ro/La antibodies to aortic dilation in patients with congenital complete heart block

An association between congenital complete atrioventricular block (cCAVB) and aortic dilation during childhood has recently been reported. We sought to further explore this relation with particular emphasis on the natural history of aortic abnormalities over time. The relation of maternal anti-Ro/La antibody status to the aortic size of children affected with cCAVB was also assessed. The patients were evaluated longitudinally with serial echocardiography. During a 15-year period, 62 patients at our institution were diagnosed with cCAVB, of whom 40% were exposed to maternal autoimmune antibodies and 35% were not. The antibody status in the remaining patients was unknown. The patients underwent 9.3 ± 6.5 echocardiograms during the follow-up period. Dilation of the ascending aorta, defined as a z score >2.0, was present on the initial echocardiogram in all patients exposed to maternal antibodies and persisted during long-term follow-up in 96% of these patients. In contrast, 5% and 10% of patients without exposure to maternal autoimmune antibodies had aortic dilation on the initial and follow-up studies, respectively (p <0.001 and p <0.001, respectively). In conclusion, patients with autoimmune-mediated cCAVB merit periodic echocardiographic monitoring into adulthood to assess persistent or progressive aortic dilation and its attendant complications.