Spontaneously disappearing right atrial mass in a preterm infant: a case report

BACKGROUND: There is currently a lack of evidence-based guidelines regarding ideal management of a neonate, specifically a preterm, with thrombo-embolus. There are no clear guidelines as to the time-frame of spontaneous resolution of a thrombo-embolus. CASE SUMMARY: A large pedunculated right atrial mass was identified on a clinician-performed cardiac ultrasound in a preterm neonate. The mass was smaller than half of the atrial size and was not causing obstruction. The mass disappeared spontaneously within 6 days and was retrospectively presumed to have been a thrombus. The neonate remained asymptomatic with no signs suggesting that the mass may have embolized. DISCUSSION: In this case of an incidentally identified asymptomatic intracardiac mass in a preterm infant, presumed to be a thrombus, our conservative ‘wait and watch’ approach was not associated with any adverse pulmonary or systemic effects.