Paraganglioma and cyanotic congenital heart disease: The role of tisular hipoxia.

Cyanotic congenital heart disease (CCHD) refers to a group of heart diseases which occur after birth, affect 1/1000 live newborns, and are associated with systemic hypoxia. The incidence of congenital heart disease ranges from 12 to 14/1000 live newborns.1 The different congenital cardiac defects may cause increased pulmonary vascular resistance and pulmonary hypertension, so that approximately 8% of all congenital heart diseases and 11% of those with left-toright shunts develop Eisenmenger’s syndrome, characterized by progressive pulmonary vascular involvement and cyanosis resulting from systemic-pulmonary communication which causes shunt reversal. Eisenmenger’s syndrome is the most common cause of CCHD in adults.2 Pheochromocytoma (PC) and paraganglioma (PG) are neuroendocrine tumors arising from chromaffin tissue which have a low incidence in the general population and a 0.2--0.6% prevalence in patients with high blood pressure. In more than 30% of cases, the occurrence of these tumors has been reported to be related to genetic changes.3 Some publications have reported the coexistence of both conditions, and a potential pathogenetic association has been postulated. We report the case of a 41-year-old female patient diagnosed in childhood with congenital heart disease consisting of single double-chambered left ventricle with l-malposition