Poster: CT-514 Acute Cardiac Tamponade Following Adult Allogeneic Hematopoietic Transplantation

Large pericardial effusions (LPEs) occur in <1% of the adult population. Early onset (<100 days from allogeneic hematopoietic transplantation (allo-SCT)) LPEs are related to cardiac toxicity of conditioning regimen while late LPEs (>100 from allo-SCT) are chronic GvHD related. The major determinant of acute pericardial tamponade (ACT) is the rapidity with which fluid accumulates. We herein document 4 adult patients with early LPEs that led to ACT. Interestingly, 3 of these also manifested idiopathic immune thrombocytopenia (ITP), an association that has not been previously described. Median age of 3 females and 1 male was 46 years (range 19-58). All patients received high-dose cyclophosphamide either as part of conditioning or post-transplant GvHD prevention (conditioning comprised: busulfan, fludarabine and tiotepa and post-transplantation cyclophosphamide =1, cyclophosphamide, total body irradiation and alemtuzumab =2 and cyclophosphamide and antithymocyte globulin =1). Donors comprised: matched unrelated donor =2, matched sibling donor =1 and haploidentical donor =1. Engraftment occurred on days +20, +30, +12, and +21. All four patients developed ACT at <100 days from allo-SCT on days +1, +16, + 22, and +60 after allo-SCT. ACT manifested as acute, new, or worsening shortness of breath. At ACT, all 4 were negative for CMV infection and acute GvHD (aGVHD). Pericardial fluid was serous in 2 and serosanguinous in 2 patients. Laboratory analysis did not support bacterial or viral infections and rheumatologic profile was negative. ACT was managed by cardiologist who performed either pericardiocentesis with pericardial drain or pericardial window. A cumulative total of 1700 ml, 1500 ml, 1500 ml and 300 ml pericardial fluid was removed. LPEs reoccurred in 2 patients; one with ACT physiology required pericardial window. Additionally, 3 patients developed ITP after development of ACT. The median time to ITP was day+30 (30, 30 and 75 days) from engraftment. Bone marrow biopsies in patients who developed ITP revealed adequate megakaryocytes. ITP responded promptly to steroids, thrombopoietin receptor agonists and IVIG. Prompt cardiac evaluation with doppler echocardiogram facilitates lifesaving management of ACT. Early onset LPEs in our patients was not associated with aGVHD; it is more likely to be associated with cardiac toxicity of cyclophosphamide. Association with ITP may reflect shared pathogenesis.