1Sami Ulus Maternity and Children Research and Training Hospital, Ankara, Turkey
2Pediatric Cardiology and Neonatology, Ankara, Turkey
ABSTRACT The valves of right horn of systemic venous sinus are prominent structures within the right atrium during early embryonic period. Involution of these structures may not be complete, resulting in a spectrum of anatomical presentations such as cyanosis. A full-term male neonate referred to our hospital for precise evaluation of severe cyanosis on the first day of life. Echocardiographic examination revealed right-to-left interatrial shunting through patent foramen ovale due to prominent eustachian valve with normal estimated right heart pressures from peak tricuspid regurgitation velocity. He was maintained with supplemental oxygen and a PDE-5 inhibitor (sildenafil) and subsequently improvement in oxygen saturation was achieved. The patient was discharged after 2 weeks of treatment. In conclusion; the embryologic remmants of the sinus venosus rarely may lead to right-to-left shunting resulting in severe cyanosis. Pulmonary vasodilators such as sildenafil may improve oxygen saturation in these patients even in case of normal right heart pressures.
References 1. Bendadi F, van Tijn DA, Pistorius L, Freund MW. Chiari’s network as a cause of fetal and neonatal pathology. Pediatr Cardiol. 2012; 33:188–91 2. Yasuda K, Iwashima S, Sugiura H, Ohki S, Seguchi M. Intermittent cyanosis due to prominent eustachian valve in a newborn infant. The Journal of Maternal-Fetal & Neonatal Medicine. 2009; 22:9, 812-5 3. Ko HS, Chen MR, Lin YC. A huge Chiari network presenting with persistent cyanosis in a neonate. Pediatr Cardiol. 2011;32:239–40 4. Qureshi AU, Latiff HA, Sivalingam S. Persistent valve of systemic venous sinus: a cause of neonatal cyanosis. Cardiology in Young. 2014;24:756–9 5. Farrow KN, Groh BS, Schumacker PT, Lakshmi-nrusimhaS, Czech L, Gugino SF, Russel JA, Steinhorn RH. Hyperoxia increases phosphodiesterase 5 expression and activity in ovine fetal pulmonary artery smooth muscle cells. Circ Res. 2008;102:226–33. 6. Porta FM, Steinhorn RH. Pulmonary vasodilator therapy in the NICU: Inhaled nitric oxide, sildenafil, and other pulmonary vasodilating agents. Clin Perinatol 2012; 39: 149–64.