Complete heart block secondary to bortezomib use in multiple myeloma.

Although rare, cardiac rhythm abnormalities have been documented with bortezomib use in clinical trials. These side effects must be recognized promptly by physicians of various specialties as well as pharmacists. Special attention is required in patients with liver function abnormalities, elderly and patients with pre-existing cardiac conditions. Prompt bortezomib withdrawal is essential in these cases as it may prevent dismal outcomes. This is the first report of a complete heart block caused by bortezomib in the setting of myeloma therapy outside a clinical trial. The author discusses further various heart rhythm and other autonomic nervous system abnormalities attributed to bortezomib in the existing literature.