Atrial fibrillation and thrombus in a patient with a fontan circulation: Submitted by Lara Curran, MBBS, BSc, Konstantinos Dimopoulos, MD, MSc, PhD, FESC and Rafael Alonso-Gonzalez, MD, MSc, FESC

1. All patients with ACHD and AF, atrial flutter, or intraatrial reentrant tachycardia should undergo transthoracic and transesophageal echocardiography to rule out a thrombus prior to cardioversion. 2. In patients with Fontan operation presenting with AF, flutter, or IART, the search for an intracardiac thrombus should be performed regardless of the duration of the arrhythmia and prior anticoagulant therapy. 3. Fontan patients with a large intracardiac thrombus should be considered for surgical removal of the thrombus. Conversion to a newer style Fontan can be combined with the thrombectomy operation.