Bortezomib-Induced Congestive Cardiac Failure in a Patient with Multiple Myeloma

Bortezomib therapy is known to be associated with neurological side effects and thrombocytopenia. Its cardiac side effects are however not well known. The patient, a 70-year-old woman, with a previous history of myocardial infarction and subsequent coronary stenting, was detected to have multiple myeloma stage IIIa. She was started on Inj. Bortezomib (1.3 mg/m(2)) and Tab. Dexamethasone 40 mg on a weekly basis. She showed good response to therapy. Three days after administration of the 22nd dose of bortezomib, she presented to the hospital with congestive cardiac failure. Echocardiography revealed a drop in the left ventricular ejection fraction from pretreatment levels of 45-50 to 25%. Patient was treated medically for left ventricular failure secondary to a suspected ischemic etiology. Coronary angiography revealed non-critical coronary artery disease with patent right coronary artery and left circumflex stents. The N-terminal pro-brain natriuretic peptide (NT-proBNP) levels that were initially raised 4,030 pg/ml (< 125 pg/ml) declined to 2,280 pg/ml a week later and subsequently normalized over the next 2 weeks. The patient responded well to treatment and was then discharged. The left ventricular ejection normalized over the next 3 months. Cardiac side effects of bortezomib are not well reported. Elderly patients and those with preexisting cardiac conditions could be at increased cardiovascular risk. Since this risk increases once a cumulative dose of 20 mg/m(2) has been administered, patients need to be monitored more intensively once this threshold has been attained. Increased awareness of these cardiac side effects is necessary for patients' safety.