Angiotropic lymphoma (AL) is an unusual variant of extranodal lymphoma, characterized by massive proliferation of neoplastic lymphoid cells almost exclusively within blood vessels. Whereas the lymphoid origin of this disease is widely accepted it still remains unclear whether AL is a distinct entity that originates in the blood vessels or whether it represents a form of secondary intravascular dissemination of a primary solid lymphoma. The present case is unusual because death by right heart failure owing to extensive intravascular proliferation of neoplastic cells and subsequent occlusion of pulmonary blood vessels has not been described so far. In addition, the patient had suffered from a solid deposit of a large-cell B-lymphoma months before the angiotropic manifestation, suggesting that AL might develop out of more common types of non-Hodgkin's lymphomas.