06/07/2023
Chiari network is an embryonic remnant of the right sinus venosus. It appears as a thin, fenestrated membrane attached to two or more regions within the right atrium along the ridge connecting vena cavae and interatrial septum. In echocardiography, Chiari network appears as free floating curvilinear structure that waves with blood flow in RA ,Chiari network is thought to a variant of Eustachian valve. A part of Chiari network arises from the or***ce of IVC like Eustachian valve, but Chiari network is much more mobile and thinner. In echocardiography, Chiari network may be confused for tricuspid vegetation, flail tricuspid valve, free RA thrombus, and pedunculated tumors. Careful tracing to identify its attachment to the or***ce of IVC makes a differential diagnosis. Chiari network has little clinical significance, but it might cause trouble during percutaneous procedures. The cases of entrapment of right-heart catheters, or entanglement and herniation into the LA by atrial septal defect occluding device have been reported.
