Mass in the left atrial appendage: a therapeutic dilemma.

This is a case of a persistent mobile mass in the left atrial appendage in which 3-dimensional transesophageal echocardiography provided excellent definition of the contour of the mass and helped in comparison during follow-up. The mass was incidentally found before atrial fibrillation ablation and initially thought to be a thrombus. As it persisted almost unchanged despite adequate anticoagulation, a tumour such as a fibroelastoma became the leading possibility, presenting us with a management dilemma. Ablation was cancelled, and, because the mass was stable with no embolic sequelae, a conservative approach was adopted. The patient was discharged on long-term anticoagulation.