Bortezomib-Induced Cardiac Tamponade in a 49-Year-Old Man.

Proteasome inhibitors such as bortezomib and carfilzomib have been used effectively to treat patients who have certain hematologic malignancies. Proteasome activity is elevated in the heart, and potent inhibition results in accumulation of misfolded intracellular protein aggregates and apoptosis. Heart failure, conduction disturbances, and premature atherosclerosis have been associated with bortezomib therapy. We describe the case of a 49-year-old man who was taking bortezomib for graft-versus-host disease, when he developed cardiac tamponade and needed emergency pericardiocentesis. At that time, there was no evidence of graft-versus-host disease. To our knowledge, this is the first time that a pericardial effusion without underlying cardiac dysfunction has been reported in relation to bortezomib therapy. The diagnosis of pericardial effusion during bortezomib therapy, the absence of other causative agents-including graft-versus-host disease-and no recurrence of pericardial effusion after discontinuing bortezomib therapy suggest that bortezomib caused our patient's tamponade.