RESUMO
We present a case of a full-term female neonate who presented at 6 h of age with severe cyanosis and was partially responsive to oxygen supplementation. An echocardiogram showed an isolated congenital severe tricuspid valve insufficiency due to rupture of the papillary muscle of the anterior tricuspid valve leaflet. Magnesium sulfate was infused to lower the pulmonary resistance and thus enhancing the antegrade pulmonary blood flow. Ductal patency was secured by prostaglandin infusion thus providing an additional pulmonary blood flow through the ductus arteriosus. The above measures were adequate to stabilize the patient with no further deterioration or the need for other supportive measures such as Nitric Oxide therapy or extracorporeal membrane oxygenation (ECMO). Therefore, early diagnosis and adequate measures to improve the pulmonary blood flow are mandatory, important pre-operative measures in the management of these patients.