Echocardiography is first-line examination of cardiac tumors. We report the case of a 25-year-old woman with a right atrial transmural invasive lipoma, and we review 58 published reports of primary cardiac invasive lipomas detected by echocardiography. We summarize the ultrasonographic characteristics and main sites of development, and examine the "invagination hypothesis". Echocardiography appears valuable for early detection, intraoperative monitoring, and postoperative follow-up of invasive cardiac lipomas.