Resolution of atrial thrombosis with heparin in a newborn with atrial flutter

Atrial thrombosis is a relatively rare event in children. We report a case of a newborn with AFI who after restoration of sinus rhythm, developed atrial thrombus on a prominent Chiari network floating between the right and left atrium through the patent foramen ovale. The thrombus was resolved following treatment with heparin without events. Conclusion: Atrial stunning was proposed as a key mechanistic phenomenon because the thrombus occurred after the cardioversion of AFI to sinus rhythm. Heparin may be effective in the resolution of atrial thrombus within a few days.