Floating right atrial mass in a patient with suspected chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a late complication of acute pulmonary embolism (PE), characterized by persistent elevation of pulmonary artery pressure and pulmonary vascular resistance due to narrowing and/or obstruction of pulmonary arteries. In some cases, thromboembolic obstruction of pulmonary artery branches may occur without pulmonary hypertension after PE (chronic thromboembolic disease — CTED). Importantly, treatment strategies for CTED and CTEPH differ. Difficulties arise in determining the optimal management for patients with previous PE, CTEPHtypical lesions on CT pulmonary angiography and mobile right heart mass (tumor, thrombus, vegetation), particularly when right heart catheterization carries a high risk of complications. We present a 50-year-old female with previous massive PE. Followup examination revealed a mobile right atrial mass interpreted as “myxoma/thrombus” and signs of thromboembolic involvement of the right pulmonary artery branch. The patient underwent surgical removal of the right atrial mass and pulmonary thromboendarterectomy from the right pulmonary artery branch. Morphological examination confirmed organized thrombi in pulmonary artery branches and a large “old” thrombus in the right atrial cavity attached to the Eustachian valve by thin connective tissue strands. This case illustrates diagnostic challenges of CTED/CTEPH in the presence of intracardiac masses and underscores the role of surgical methods in diagnosis and treatment.