Vanishing right ventricular outflow obstruction: an unusual presentation of mediastinal lymphoma

A 23-year-old patient referred for cardiac evaluation in view of easy fatiguibility, significant weight loss, and a systolic murmur. Examination revealed muscle wasting, lymphadenopathy, and an ejection systolic murmur in the pulmonary area. Mediastinal widening was seen on chest X-ray. Echocardiography showed a large extracardiac soft tissue mass compressing the right ventricular outflow tract (RVOT) and main pulmonary artery ( Panel A) with turbulent flow across the RVOT (Panel B) (see Supplementary material online, Video S1–S3) and a peak systolic gradient of 55 mmHg (Panel C). There was no intra-cardiac mass. Computed tomography revealed a large mediastinal mass (Panel D) which proved to be diffuse large B-cell lymphoma (DLBCL), CD-20+, on biopsy. The patient was treated with Rituximab-Cyclophosphamide-Doxorubicine-Vincristine-Prednisolone (R-CHOP regimen) based chemotherapy with excellent clinical and radiological response. Echocardiography 3 months after treatment showed resolution of the mass with normal spectral and colour-Doppler assessment of flow across the RVOT (Panels E and F) (see Supplementary material online, Video S4). Diffuse large B-cell lymphoma is the most common form of Non-Hodgkin's lymphoma, accounting for up to 30% of cases. It is an aggressive tumour. Patients typically present with nodal or extranodal disease, exhibiting rapid tumour growth and symptoms depending on the tumour localization. Diffuse large B-cell lymphoma presenting primarily to a cardiologist with RVOT obstruction is extremely rare. The most widely used treatment is R-CHOP. If left untreated, DLBCL has a median survival of <1 year. Supplementary material is available at European Heart Journal online.