Prenatal heart block screening in mothers with SSA/SSB autoantibodies: Targeted screening protocol is a cost-effective strategy.

OBJECTIVE: Maternal anti-Ro/SSA and anti-La/SSB antibodies can lead to fetal complete heart block (CHB). Current guidelines recommend weekly echocardiographic screening between 16 and 28 weeks gestation. Given the cost of screening and the rarity of conduction abnormalities in fetuses of mothers with low anti-Ro levels (<50 U/mL), we sought to identify a strategy that optimizes resource utilization. DESIGN: Decision analysis cost-utility modeling was performed for three screening paradigms: "standard screening" (SS) in which mid-gestation mothers are screened weekly, "limited screening" (LS) in which fetal echocardiograms are avoided unless the fetus develops bradycardia, and "targeted screening by maternal antibody level" (TS) in which only high anti-Ro values warrant weekly screening. A systematic review of existing literature and institutional cost data were used to define model inputs. RESULTS: The average cost of LS, TS, and SS was $8566, $11 038, and $23 279, respectively. SS was cost-ineffective with an incremental cost-effectiveness ratio (ICER) of $322 756 while TS was cost-effective with an ICER of $43 445. CONCLUSION: While the efficacy of fetal intervention for first or second degree AV block remains unclear, this analysis supports utilizing antibody levels to stratify this population for optimized surveillance for CHB. SS is cost-ineffective and results in resource overutilization.

Pulsed Doppler fetal atrioventricular interval measurement: Assessment of a new image scoring method.

OBJECTIVES: We propose an image scoring method to improve the quality and the reproducibility of measurement of the AV interval before establishing reference tables of the measurements and studies on the prevention and treatment of first-degree AV block especially if the first child has been diagnosed AV block. METHOD: Prospective study from May 2015 to June 2016. Sonographers were asked to measure AV interval with pulsed Doppler in a five-chamber view in standard second-trimester screening before and after having received our image scoring method. Images were scored by 2 blinded reviewers. RESULTS: The intra-class correlation coefficient (ICC) between the two reviewers for the overall score was 0.91. On average, the measurement quality increased by 2.5 points/10 (95% CI 1.0-4.0). In the second set of images, after the scoring method was given, the score stared at 6.50 for the first image, with a significant improvement of 0.18 (p = 0.016) per subsequent image comparing to a non significant improvement for the first set of image. There was a significant improvement in intra-observer reliability, ICC: 0.680 [95% CI 0.606-0.854] versus 0.458 [95% CI 0.140-0.651]. CONCLUSION: The use of this scoring method is simple, reproducible and improves image quality and reproducibility of AV interval measurement in a five-chamber view.

Fetal long QT syndrome manifested as atrioventricular block and ventricular tachycardia: a case report and a review of the literature.

Fetal onset of congenital long QT syndrome (LQTS) is a rare manifestation, and prenatal diagnosis is difficult. This report describes a boy who presented with both atrioventricular (AV) block and ventricular tachycardia during the antenatal period. The early postnatal electrocardiogram showed prolongation of the QT interval and AV block, subsequently leading to a polymorphic ventricular tachycardia torsade de pointes. This unique feature of congenital LQTS has a poor outcome, but the boy was successfully treated with beta-blockers and implantation of an automated cardioverter-defibrillator. The intrauterine manifestation of fetal AV block and ventricular tachycardia should raise a high suspicion of congenital LQTS, and the strong association with a malignant clinical course should warrant special evaluation. The literature on the prenatal diagnosis, fetal therapy, and neonatal outcome of this condition also are reviewed.

[A new method in fetal heart electrophysiology - fetal magnetocardiography]. / Neue Möglichkeiten der fetalen Herzdiagnostik - fetale Magnetkardiografie.

Fetal magnetocardiography (fMCG) is used as a non-invasive method for registering the electrophysiological fetal heart activity. Superconducting quantum interference device-based magnetometers are currently used to make fMCG recordings. In contrast to fetal ECG, this method is independent of signal loss due to isolating factors such as, especially, the vernix caesaroa between the 27th and 34th weeks of gestation. We report about a term newborn with a third degree AV block, examined by this method.

Bloqueo cardiaco fetal completo: reporte de dos casos y revisión de la literatura / Fetal complete atrioventricular block: two case report and literature review

Presentamos 2 casos de embarazos controlados en nuestro servicio con el diagnóstico de bloqueo aurículo-ventricular fetal. Este es un tipo de arritmia poco frecuente, relacionado con la presencia de anticuerpos antiribonucleoproteínas (Ro y La). El manejo es expectante en la mayoría de los casos ya que no existe forma de revertir el bloqueo; en caso de evidenciar una descompensación hemodinámica fetal, se pueden administrar corticoides como medida terapéutica con un éxito limitado. No existe contraindicación del parto vaginal y el uso de pH de cuero cabelludo y oximetría de pulso parecen ser métodos adecuados para la evaluación de la condición fetal intraparto. Recomendamos el enfoque multidisciplinario en esta patología para evitar intervenciones innecesarias, anticipar los riesgos fetales y obtener un mejor pronóstico postnatal.

Here we report the perinatal outcome of two patients with fetal complete atrioventricular (AV) block. This is an uncommon disease, related to the presence of autoantibodies against ribonucleoproteins (Ro and La). Management should be expectant in most cases because a treatment to revert the AV block is not available; when fetal hemodynamic problems are detected corticosteroids can be used, but with limited effectiveness. Vaginal delivery is allowed; fetal scalp pH and pulse oximetry are appropriate for intrapartum fetal surveillance. We recommend a multi disciplinary approach to avoid unnecessary interventions, anticipate fetal risk and obtain a better perinatal outcome.

Prenatal diagnosis of polymorphic ventricular tachycardia using 64-channel magnetocardiography.

We describe polymorphic ventricular tachycardia (VT) diagnosed using fetal magnetocardiography (FMCG). The fetus of a 33-year-old Japanese female at 24 weeks of pregnancy was diagnosed as bradycardia (60 beats/min) by fetal cardiotocography (CTG). Ultrasound findings indicated a diagnosis of an atrioventricular (AV) block involving extrasystole, but FMCG revealed a polymorphic VT followed by ventricular asystole. Standard ECG immediately after cesarean section at 37 weeks of pregnancy confirmed long QT syndrome followed by nonsustained polymorphic VT and an advanced AV block with wide QRS. Echocardiography demonstrated moderate left ventricular dysfunction in the neonate requiring implantation with a permanent pacemaker.

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.

A management strategy for fetal immune-mediated atrioventricular block.

INTRODUCTION: The purpose of this study is to describe an in utero management strategy for fetuses with immune-mediated 2° or 3° atrioventricular (AV) block. METHODS AND RESULTS: The management strategy as applied to 29 fetuses consisted of three parts. First, using fetal echocardiography and obstetrical ultrasound, we assessed fetal heart rate (FHR), heart failure, growth and a modified biophysical profile score (BPS) assessing fetal movement, breathing and tone. Second, we treated all fetuses with transplacental dexamethasone, adding terbutaline if the FHR was<56 bpm. Digoxin and/or intravenous immune globulin (IVIG) was added for progressive fetal heart failure. Third, we delivered fetuses by cesarean section for specific indications that included abnormal BPS, maternal/fetal conditions, progression of heart failure, or term pregnancy. We assessed perinatal survival, predictors of delivery and maternal/fetal complications in 29 fetuses with 3° (n=23) or 2° (n=6) AV block. There were no fetal deaths. In utero therapy included dexamethasone (n=29), terbutaline (n=13), digoxin (n=3) and/or IVIG (n=1). Delivery indications included term gestation (66%), fetal/maternal condition (14%), low BPS (10%) and progression of fetal heart failure (10%). An abnormal BPS correlated with urgent delivery. CONCLUSION: These results suggest that applying this specific management strategy that begins in utero can improve perinatal outcome of immune-mediated AV block.

Diagnostic precision of Doppler flow echocardiography in fetuses at risk for atrioventricular block.

OBJECTIVE: To investigate the diagnostic precision of three Doppler methods in their ability to predict postnatal first-degree atrioventricular (AV) block. METHODS: This was a prospective, observational study carried out from December 1999 to March 2008, including 95 fetuses of anti-SSA/Ro positive mothers undergoing weekly fetal echocardiograms at 18-24 weeks' gestation. Doppler-derived AV time intervals for left ventricular inflow (MV), inflow and outflow (MV-Ao) and superior vena cava a-wave to aortic flow (SVC-Ao) were compared with the PR interval on postnatal electrocardiography. Reference values for MV intervals were established from 102 healthy fetuses, with previously published reference ranges used for the two other methods. Bayesian and receiver-operating characteristics (ROC) curve analyses were performed. RESULTS: The prevalence of first-degree AV block at birth was 13.8%. Using a cut-off at the upper 95% confidence limit, MV-Ao and SVC-Ao time intervals had a sensitivity of 91.7%, and negative predictive value and negative likelihood ratio of 98.4% and 0.10, respectively. The corresponding positive predictive value/positive likelihood ratio for MV-Ao and SVC-Ao were 42.3%/4.5 and 47.8%/5.7, respectively. The areas under the ROC curve (AUC) for MV-Ao and SVC-Ao were 0.87 and 0.89, respectively (both P < 0.001), with generated cut-offs for abnormal AV time intervals at 134-138 and 132-138 ms. MV time intervals using a cut-off at the upper 95% confidence limit had a sensitivity of just 50% and an AUC of 0.74 (P < 0.01). CONCLUSION: The MV-Ao and SVC-Ao Doppler methods make it possible to identify nearly all fetuses with first-degree AV block at birth and to exclude conduction disturbances in the case of a normal AV time measurement but at the cost of a positive predictive value of 50%.

Early diagnosis and treatment of atrioventricular block in the fetus exposed to maternal anti-SSA/Ro-SSB/La antibodies: a prospective, observational, fetal kinetocardiogram-based study.

BACKGROUND: A fetus exposed to maternal anti-SSA/Ro or anti-SSB/La antibodies (or both) may develop complete atrioventricular block (AVB), which results in high prenatal and postnatal morbidity and mortality. Until recently, only high-grade AVB could be diagnosed in utero. The tissue velocity-based fetal kinetocardiogram (FKCG) enables accurate measurement of AV conduction time and diagnosis of low-grade AVB. In the present multicenter observational study, we used FKCG to detect first-degree AVB in fetuses at risk. METHODS AND RESULTS: FKCG was performed in 70 fetuses of 56 mothers who were positive for anti-SSA/Ro and/or anti-SSB/La. Fetuses were monitored with weekly FKCG from 13 to 24 weeks' gestation, followed by monthly assessments until delivery in unaffected fetuses and weekly assessments in affected fetuses. AV conduction in 70 at-risk and 109 normal fetuses was compared. FKCG was obtained readily in all fetuses; 6 showed first-degree AVB (AV conduction time >2 z scores above normal mean) at 21 to 34 gestational weeks. Immediate maternal treatment with dexamethasone resulted in normalization of AV conduction in all affected fetuses within 3 to 14 days. AV conduction time in the remaining 64 untreated fetuses remained normal throughout gestation. The ECG PR interval immediately after birth was normal in all affected newborns. No child developed AVB or cardiomyopathy in the subsequent 1- to 6-year (median 4-year) follow-up. CONCLUSIONS: The present findings suggest that an FKCG can detect first-degree AVB in the fetus exposed to maternal anti-SSA/Ro or anti-SSB/La antibodies (or both). Dexamethasone given on detection was associated with normalized AV conduction in fetuses with first-degree AVB. No fetus in the present study developed complete prenatal or postnatal AVB.