| A rare congenital anomaly of the inferior vena cava with characteristics of the postnatal presence of a eustachian valve remnant that may be asymptomatic and considered a normal variant or prominent and clinically significant. Clinical presentation is variable and includes obstruction of the inferior vena cava, cyanosis, thrombosis, pulmonary embolism, and infective endocarditis and when combined with persistent foramen ovale it may generate permanent right-to-left shunt. |