BACKGROUND There are no guidelines providing an algorithmic approach for the management of right atrial thrombi, to date, owing to a lack of strong supporting studies. In this case series, we describe 2 cases of high-risk patients with massive right atrial thrombi who had different outcomes. CASE REPORT Case 1: A 62-year-old man with ischemic cardiomyopathy and atrial fibrillation, who was on a permanent pacemaker for sick sinus syndrome and was noncompliant with medication for 2 years, presented to the Emergency Department for evaluation of a 2-month history of progressive shortness of breath and swollen neck veins. A cardiac ultrasound confirmed a large right atrial thrombus, and a computed tomography (CT) pulmonary angiogram was negative for pulmonary emboli. He was managed with a heparin infusion and thrombolytic therapy with favorable evolution. Case 2: A 66-year-old man, with a past medical history of nonischemic cardiomyopathy, atrial fibrillation, deep venous thrombosis, and pulmonary emboli a year earlier, presented to an urgent care unit with sudden onset of shortness of breath. A cardiac ultrasound confirmed a large right atrial thrombus, and a CT pulmonary angiogram confirmed bilateral pulmonary emboli. He was managed with a heparin infusion and EkoSonic endovascular system therapy. He subsequently needed venoarterial extracorporeal membrane oxygenation for cardiopulmonary resuscitation and underwent mechanical aspiration thrombectomy. The patient's evolution was unfavorable. CONCLUSIONS In the absence of an evidence-based guideline to approach right atrial thrombi, management should be individualized for each patient, based on the type of thrombi, hemodynamic status, and presence or absence of associated pulmonary emboli.