Heart failure after a bone marrow transplant: what is your diagnosis?

An extensive, protruding, irregular thrombus fills the whole right ventricular apex, the mid cavity and most of the outflow tract, which is partially obstructed. The right ventricle is not dilated, yet its function falls to an RVEF of 30%, and cardiac output is only 1.63 l/min. The answer video runs through the short axis from base to apex.

Pearls

• A ventricle filled from within. In endomyocardial fibrosis the apex is obliterated by fibrosis and thrombus. That is why the right ventricle does not dilate even as it fails: the usable cavity shrinks.
• The right heart speaks of pressure. A moderately dilated right atrium, an interatrial septum bowing to the left throughout the cycle and a flattened interventricular septum. This is the signature of high filling pressures.
• Look at the enhancement under the thrombus. There is faint apical right ventricular enhancement. The left ventricle has no focal fibrosis but does show septal oedema (T2 77 ms, native T1 1083 ms): the disease is still active.
• Eosinophilia is the clue. With an eosinophil count above 1,000, a thrombus lining the apex should raise eosinophilic endomyocardial involvement, not just an isolated thrombus.
• Differentials. The findings do not suggest tumour infiltration from the lymphoma. The central venous catheter sits in the superior vena cava, whereas the thrombus lines the right ventricular apex and outflow tract.
• What comes with it. A chronic-looking, moderate to severe pericardial effusion without tamponade, and moderate bilateral pleural effusions.