Myxomas comprise 50% of all benign cardiac tumors in adults, with the right atrium as their second most frequent site of origin. Surgical resection is the only effective therapeutic option for patients with these tumors. The association between right atrial myxomas and severe left ventricular systolic dysfunction is extremely rare and makes treatment even more challenging. This was the case for our patient, a 47-year-old male with a right atrial mass and a severely impaired left ventricular function, with a 20% ejection fraction. Global enlargement of the heart was also noted, with moderate right ventricular dysfunction. The tumor was successfully excised using the on-pump beating heart technique, with an immediate postoperative improvement of the left ventricular ejection fraction to 35%. The technique proved useful, with no increased risk to the patient.