Cardiac myxomas are the most common benign primary tumors and are most often located in the left atrium at the level of the interatrial septum, with the characteristic of being pedunculated and highly mobile, which is why they sometimes interfere with the functioning of the mitral valve, generating variable degrees of stenosis and mitral insufficiency. Diagnosis is by echocardiography and treatment is surgical resection. We present the case of a patient with a large atrial myxoma and severe double mitral lesion.