Case report and literature review: cardiac tamponade as a complication of pericardial extramedullary hematopoiesis.

Pericardial effusion can cause cardiac tamponade physiology with resultant cardiogenic shock and death. Myelofibrosis, the replacement of marrow cavity by fibrous connective tissue, is a secondary complication of a group of disorders known as myeloproliferative neoplasms, which are clonal processes characterized by abnormal proliferative growth of one or more hematopoietic lineages. One consequence of myelofibrosis is the development of hematopoiesis at other anatomic sites, most commonly the spleen and liver, a phenomenon known as extramedullary hematopoiesis (EMH). Herein we report a case of a man who died from pericardial tamponade due to a subacute pericardial effusion secondary to EMH in the pericardium in the setting of myelofibrosis. This case highlights an unusual etiology for pericardial effusion and tamponade that should be considered in cases of myelofibrosis and stimulates a discussion regarding the mechanisms and anatomic distribution of EMH.