When Myxoma Jumps Chambers: Direct Seeding from Left Atrium to Right Ventricular Outflow Tract via Patent Foramen Ovale

A 57-year-old man presented with progressive exertional dyspnea and paroxysmal nocturnal dyspnea over 2 weeks.On auscultation, a low-pitched diastolic rumbling murmur was audible at the apex.Transthoracic echocardiography revealed a large, mobile mass (7.5 × 4.5 cm) attached to the mid-atrial septum, prolapsing into the mitral orifice during diastole and generating a mean transvalvular gradient of 32 mm Hg (Figure 1A).Strikingly, a second, well-circumscribed mass (2.7 × 2.0 cm) was identified in the right ventricular outflow tract, with no internal vascularity on Doppler imaging (Figure 1B).Contrast-enhanced cardiac computed tomography confirmed dual intracardiac masses and visualized a patent foramen ovale (PFO) connecting the 2 chambers (Figure 1C-E).Both tumors were surgically resected (Figure 1F-G), and histopathology confirmed identical benign myxoma morphology in both specimens-stellate cells embedded in a myxoid stroma (Figure 1H).The patient recovered uneventfully and remained recurrence-free at 2-year follow-up.Cardiac myxoma, the most common primary cardiac tumor, typically presents as a solitary lesion with approximately 75% occurring in the left atrium.1,2 While