Lipomatous hypertrophy of the interatrial septum demonstrated by three-dimensional transesophageal echocardiography.

respectively. Electrocardiography (ECG) showed sinus rhythm with a normal axis. The chest X-ray was unremarkable. Two-dimensional (2D) and real-time 3-dimensional (3D) transthoracic echocardiography (TTE) revealed a very mobile (characterized by whip-like motion), thin, filamentous structure in the right atrium (Chiari network) prolapsing into right ventricle through the tricuspid orifice during diastole (Fig.1, 2, Video 1-5. See corresponding video/movie images at www.anakarder.com). Other echocardiographic findings were normal. After injection of agitated saline into an upper extremity vein was not detected right-to-left shunt by transthoracic contrast echocardiography. Therefore, we recommended echocardiographic follow-up to the patient. Chiari network is a congenital remnant of the right valve of the sinus venosus, which was first described by Dr. Hans Chiari in 1897 in an autopsy series. Chiari network is often diagnosed incidentally and estimate prevalence is 2% in TEE and 1.5% in TTE studies. Generally this congenital remnant considered clinically insignificant but it may be associated with patent foramen ovale (in about 80% of patients), intraatrial thrombus, thromboembolic events, formation of inter-atrial septal aneurysm, infective endocarditis, supraventricular arrhythmias and catheter entrapment.