Immune-Mediated Fetal Complete Atrioventricular Block: Can Dexamethasone Therapy Revert the Process?

BACKGROUND: Fetal complete atrioventricular block (CAVB) is usually autoimmune mediated. The risk of developing CAVB is 2% to 3% in anti-Ro/SS-A seropositive pregnancies and it increases 10 times after previous CAVB in siblings. Despite being a rare complication, CAVB carries a 20% mortality rate and substantial morbidity, as about 65% of newborns will eventually need life-long pacing. Once found, fetal CAVB is almost always irreversible, despite aggressive immunotherapy. This poor outcome prompted some research groups to address this situation. All groups followed anti-Ro/SS-A seropositive pregnancies on a weekly basis during the second trimester of pregnancy and tried to detect first degree atrioventricular block (AVB) using accurate echocardiographic tools, assuming they may characterize the initiation of the immune damage to the A-V conduction system, at which point the process might still be reversible. Some of the groups treated fetuses with first degree AVB with maternal oral fluorinated steroids. We summarized the results of all groups, including our group. We describe a case of a fetus that developed CAVB 6 days after normal sinus rhythm (NSR), who under aggressive dexamethasone therapy gradually reverted to NSR. This fetus had a previous sibling with CAVB. We assumed the immune damage to the conduction system in this small group of fetuses with a previous CAVB sibling may have occurred more quickly than usual. We therefore recommend a twice-weekly follow-up with these fetuses.

Automated Left Ventricular Endocardial Border Detection Using Acoustic Quantification in Children.

OBJECTIVES: The purpose of this study was to determine the reliability and accuracy of automated border detection using acoustic quantification in children. BACKGROUND: Acoustic quantification has shown promise in adult patients as a method for on-line estimation of left ventricular size and function. However, in children, the smaller ventricular size might magnify the importance of measurement error. METHODS: We compared the cross-sectional area and fractional area change of the left ventricle as measured on line by acoustic quantification with the area and fractional area change derived by hand-digitizing the endocardial border of the left ventricle off line, both with and without the papillary muscles included in the left ventricular cavity. RESULTS: The areas and area change fractions from the two methods were highly correlated, both with inclusion and exclusion of the papillary muscles for off-line analysis. However, the regression slope was closer to unity when the papillary muscles were excluded from the left ventricular cavity during off-line digitization of the endocardial border. Analysis of agreement between the two methods showed good agreement for area measurements and fair agreement for function measurements. The magnitude of the difference between the two methods for area measurement was directly proportional to the size of the ventricle. That is, the larger the ventricle the larger the difference between the area measurements by the two methods. DISCUSSION: Automatic border detection using acoustic quantification appears to be an acceptable method for estimating the cross-sectional area and fractional area change of the left ventricle in children.

The natriuretic peptides as biomarkers for adults with congenital heart disease.

Thanks to improved treatment of congenital heart disease early in life, many such patients reach adulthood. Adults with congenital heart disease are an increasing population, which will continue to grow in the future. The clinical state of these patients is affected by their complex heart diseases, as well as the consequence of past corrective or palliative interventions. The natriuretic peptides are important markers for the presence, severity and prognosis of heart disease. The majority of the current knowledge is on patients with acquired heart disease. This article reviews the present knowledge regarding the role of the natriuretic peptides in adults with various forms of congenital heart disease.