Perinatal Outcome of Fetal Atrioventricular Block

Abstract

Background-Fetal atrioventricular (AV) block is an uncommon lesion with significant mortality. Because of the rarity of this disorder, the natural course, extensive evaluation of untreated fetuses, and late follow-up remain unclear. Methods and Results-Of the 116 consecutive cases of fetal AV block studied from 1988 to 2006, only 1 was terminated, and 75% were live births. Fifty-nine cases of AV block were associated with major structural heart disease, mainly left atrial isomerism (nϭ40), with only 26% of neonatal survivors. Of the 57 fetuses with normal cardiac anatomy, 41 (72%) were positive for maternal antinuclear antibodies, and 32 of these seropositive mothers did not receive any treatment. This untreated group had live-birth and 1-year infant survival rates of 93% and 90%, respectively. Five fetuses from seronegative mothers showed regression to sinus rhythm during pregnancy. The presence of major structural heart disease, hydrops, an atrial rate Յ120 bpm, and a ventricular rate Յ55 bpm were identified as risk factors for mortality. Logistic regression analysis of the whole group showed that the presence of structural heart disease was the only independent predictor of death (PϽ0.001). Conclusions-This long-term study confirms that fetal AV block has a poor outcome when associated with structural heart disease and that spontaneous regression of AV block is possible in seronegative forms. The survival rate of Ͼ90% of our untreated patients with isolated forms of AV block raises concerns about any decision to intervene with immunosuppressive agents. (Circulation. 2008;118:1268-1275.)

Evaluation of Transplacental Treatment for Fetal Congenital Bradyarrhythmia

“…6 Approximately two-thirds of antiRo/SSA antibody-positive mothers had low anti-Ro/SSA levels and probably little risk of development of fetal cardiac NLE. 8 It is unclear why the anti-Ro/SSA-positive rate in the present study was lower than in other reports. It is unlikely to be due to the sensitivity of the laboratory methods, but it is possible that other undetectable antibodies associated with congenital AVB are present in the Japanese population.…”

Response to Letters Regarding Article, “Perinatal Outcome of Fetal Atrioventricular Block: One-Hundred Sixteen Cases From a Single Institution”

“…1 We were also surprised with our results, which showed that in fetuses with normal cardiac anatomy, fetal, neonatal, and late death were not related to the presence or absence of anti-RO (SS-A) antibodies (29 positive anti-RO and 9 negative anti-RO of 38 surviving; PϾ0.05). Although our data showed no significant differences between the 2 groups in terms of fetal, neonatal, or late deaths, we agree that the finding of maternal autoantibodies is of great importance not only because they are mainly related to the genesis of the heart block (72% in our series) but also because they are related to the late outcome of maternal autoimmune diseases and dilated cardiomyopathy (DCM).…”

Arrhythmias Presenting in Neonatal Lupus

“…The presence of signs or symptoms is mainly related to the ventricular rate, which usually ranges between 30 and 100 beats ⁄ min [18,19], but may be also related to the cardiac contractility and to the ratio of atrial to ventricular contractions; heart rate usually declines during the pregnancy [20], the lower the rate, the higher the possibility of foetal hydrops and neonatal cardiac failure, and foetal or neonatal death correlates with a ventricular rate in utero £55 bpm [18][19][20][21].…”

“…On the other hand, cardiological studies generally report lower percentages of anti-Ro ⁄ SSA-positive cases (e.g. 65%), but details of methods employed to detect the antibodies often are lacking [18,21,27,28].…”