Ebstein anomaly and Trisomy 21: A rare association
A male infant was born to a 23-year-old woman with intermittent prenatal care, at 35 weeks and 2 days gestation. The prenatal ultrasound revealed a 10-fold risk of Trisomy 21 based on nuchal translucency; however, additional workup, including a fetal echocardiogram, was not performed. On the day of birth, an obstetric ultrasound revealed oligohydramnios and intrauterine growth restriction with the fetus at less than the first percentile, therefore, induction of labor ensued and the baby was born via uncomplicated vaginal delivery.\nAfter birth, continuous positive airway pressure at 5 mmHg and supplemental oxygen at 50% was instituted due to clinical cyanosis and poor respiratory effort, with a resulting oxygen saturation of 70%. The Apgar scores were 7 and 9. On physical examination there was typical facies associated with Trisomy 21 and a 2-3/6 holosystolic murmur was auscultated at the left lower sternal border. Genetic testing confirmed karyotype 47, XY + 21. A chest X-ray revealed significant cardiomegaly and increased pulmonary vascularity []. An electrocardiogram (EKG) demonstrated sinus rhythm, right atrial enlargement, intraventricular conduction delay, with an extreme rightward axis, and no pre-excitation.\nTransthoracic echocardiography performed on the first day of life [Figure –] revealed (S,D,S) normal segmental anatomy with atrioventricular and ventriculoarterial concordance. An apically displaced and tethered tricuspid septal leaflet, with a deficient posterior leaflet, resulted in mild-to-moderate tricuspid regurgitation. The right atrium (atrialized ventricle) was dilated with a right-to-left flow across a stretched patent foramen ovale. There was a moderate perimembranous ventricular septal defect (VSD) with muscular extension and mostly left-to-right flow, at a low velocity, which predicted a peak gradient of 14 mmHg. The pulmonary valve was normal without stenosis or regurgitation. A large ductus arteriosus shunted left-right on the initial echocardiogram. The left ventricular morphology was normal.\nThe patient was monitored in the Neonatal Intensive Care Unit (NICU). Once ductal closure had been confirmed on day of life #6 and as oxygen saturations remained above 90%, ensuring adequate pulmonary blood flow, the patient was discharged home on day of life #25, with close follow up and consideration of surgical intervention once symptomatic.\nFollowing initial discharge, the patient was readmitted multiple times to the hospital for failure to thrive despite maximal caloric intake. Therefore, the patient underwent tricuspid valvuloplasty and VSD closure, with maintenance of an atrial level communication on day of life #108. A postoperative echocardiogram revealed moderate-to-severe tricuspid regurgitation, estimating a gradient of 39 mmHg from right ventricle to right atrium and right-to-left shunting across the atrial communication. Initially, weight gain was steady and oxygen saturations remained above 80%; however, over several months the patient again failed to gain weight despite adequate caloric intake. An echocardiogram 6.5 months postoperatively [Figure –] demonstrated severe tricuspid regurgitation, right-to-left shunting across the atrial communication, and new mild left upper pulmonary vein stenosis, with a mean gradient of 3-4 mmHg. Cardiac catheterization revealed diffuse pulmonary vein hypoplasia and left-sided pulmonary vein stenosis, with mean gradients of 4-11 mmHg. Repeat surgical intervention of the tricuspid valve was considered, however, given the low likelihood of improvement on account of pulmonary vascular disease and high-expected morbidity, surgery was not recommended.