Parturients with Tetralogy of Fallot: a case series
Abstract Number: 99
Abstract Type: Case Report/Case Series
The congenital cardiac defect Tetralogy of Fallot (TOF) has been successfully managed to allow for survival to child bearing age. This is a case series of parturients with TOF who delivered at our tertiary care birthing center over the past decade. After IRB approval, patients were identified from the obstetric and cardiology databases; their medical records, paper and electronic, within our health system were reviewed. Of the 8 patients identified to date, accounting for 9 deliveries, all underwent corrective surgery in childhood. These patients were managed by a multidisciplinary team including maternal fetal medicine specialists, obstetric anesthesiologists, and cardiologists specializing in adult congenital defects.
Maternal co-morbidities included one patient who had a documented NSTEMI twelve months prior to delivery; she also smoked. All of our patients reported activities for daily living consistent with a NY Heart Class 1 or 2. Antenatal investigations included multiple ECHOs, EKGs, and in select cases cardiac MRIs. The most common cardiac abnormalities were RBBB and elevated RV pressures ranging from 35 - 50 mmHG by the ECHO recorded closest to the time preceding delivery; peak gradients across the PV ranged from 20 - 37 mmHg.
The modes of delivery varied - spontaneous vaginal (4), assisted vaginal (2), and Cesarean delivery, both elective (2) and emergent (1). Each laboring patient had epidural or combined spinal-epidural analgesia; general anesthesia was given after a failed epidural top up for an emergent Cesarean for fetal bradycardia. All fetuses were term except for one delivered at 34 weeks due to concern for uncontrolled fetal tachycardia. There were no maternal complications in spite of their elevated risks for arrhythmias, heart failure, ischemia, and venous thromboembolism. One patient required a blood transfusion secondary to instrumental delivery. None of these patients required invasive hemodynamic monitoring. The patient who received general anesthesia was observed in the ICU post-operatively; all others were managed on the labor ward.
One fetus had TOF and another significant congenital arrhythmia, each diagnosed by fetal ECHO. One fetus had a physical anomaly of a single missing toe. All others in our series were healthy.
In summary, at our tertiary care center all of the identified parturients with TOF had corrective surgery. The management was multidisciplinary and included frequent reassessment of the hemodynamic status throughout the pregnancy. Based on this case series, patients with corrective TOF tolerate pregnancy well and do not require a specific mode of delivery. To attenuate the associated hemodynamic changes of labor and delivery, early epidural analgesia during labor and delivery is advocated.