504: Indications for delivery of the fetus with isoimmune conduction system disease after optimal in utero management

DISEASE AFTER OPTIMAL IN UTERO MANAGEMENT MAUREEN LEE, JAMES HUHTA, JENNY LESHKO, ANDREA KEMP, BARBARA PARILLA, BETTINA CUNEO, University of Illinois at Chicago, Chicago, Illinois, University of South Florida, St. Petersburg, Florida, University of South Florida, Pediatrics, St. Petersburg, Florida, University of Illinois at Chicago, Park Ridge, Illinois, Society for Maternal-Fetal Medicine, Oak Lawn, Illinois OBJECTIVE: The optimal time for delivery of the fetus with isoimmune 2° or 3° AV block (AVB) is at term and without heart failure. We evaluated the indications for delivery after basing our in utero management on fetal heart rate (FHR) and degree of heart failure, based on a cardiovascular profile score (CVPS). STUDY DESIGN: We retrospectively reviewed medical records, echocardiograms and ultrasounds of fetuses with AVB from 2 perinatal-cardiology centers over 12 years. Weekly, from diagnosis to delivery, we monitored FHR, the CVPS (a 10-point score assessing cardiothoracic area, venous and arterial Doppler flow patterns, hydrops, and valvular insufficiency), the presence of endocardiofibroelastosis (EFE), fetal growth, and after 30 weeks, biophysical profile. Dexamethasone was given to the mother at diagnosis; we added terbutaline if CVPS 8 or FHR 55 bpm; and digoxin if CVPS was 7. Fetuses were divided into group 1 if they delivered at term and group 2 if they delivered at 36 weeks. Groups differences were tested using Fisher Exact’s test. RESULTS: All fetuses (group 1: n 13 with 3° AV block; group 2: n 8; 2 with 2° and 6 with 3° AV block) were born alive. Indications for early delivery were abnormal BPP(2), ventricular dysfunction alone(3) or with abnormal BPP(1) and oligohydramnios (1) or IUGR (1). Both group 2 fetuses with 2° AVB were delivered because of abnormal BPP. More group 2 fetuses required terbutaline (62.5% vs. 37.5%) for low FHR, had EFE (63% vs. 6 %, p .014), had lower pre-delivery CVPS (p .028), and were diagnosed earlier (p .03). CONCLUSION: The CVPS, fetal HR and the presence of EFE, but not the degree of AVB, correlated with the need for early delivery. Ventricular dysfunction is an indication for one third of premature deliveries. The CVPS is useful in monitoring the in utero management of isoimmune AVB.