Bortezomib-Induced Complete Heart Block and Myocardial Scar: The Potential Role of Cardiac Biomarkers in Monitoring Cardiotoxicity.

Bortezomib is a proteasome inhibitor used to treat multiple myeloma and mantle cell lymphoma. Traditionally, bortezomib was thought to have little cardiovascular toxicity; however, there is increasing evidence that bortezomib can lead to cardiac complications including left ventricular dysfunction and atrioventricular block. We present the case of a 66-year-old man with multiple myeloma and persistent asymptomatic elevations of cardiac biomarkers who developed complete heart block and evidence of myocardial scar after his eighth cycle of bortezomib, requiring permanent pacemaker placement. In addition to discussing the cardiovascular complications of bortezomib therapy, we propose a potential role for biomarkers in the prediction and monitoring of bortezomib cardiotoxicity.