Bortezomib-based Chemotherapy for Multiple Myeloma Patients Without Comorbid Cardiovascular Disease Shows No Cardiotoxicity.

BACKGROUND: Proteasome inhibitors used in the treatment of multiple myeloma act primarily through the disruption of intrinsic cellular protein quality maintenance, resulting in proteotoxic stress, cellular dysfunction, and, ultimately, cell death. We assessed whether evidence has shown off-target myocardial dysfunction related to the administration of bortezomib-based chemotherapy for multiple myeloma. PATIENTS AND METHODS: Patients aged 18 to 70 years who were free of significant cardiovascular disease were included. They underwent evaluations before and after each dose of bortezomib to assess for clinical, subclinical, and transient cardiotoxicity using echocardiography and serum biomarker measurement. Cardiac magnetic resonance imaging was performed at 3 separately defined intervals. The primary modality for determining subclinical myocardial dysfunction was echocardiographic assessment of the global longitudinal strain (GLS). RESULTS: Eleven patients (7 men) with an average age of 55 years were included. No evidence of cumulative myocardial dysfunction was found using echocardiographic markers, primarily GLS (average change in absolute GLS, -1.17; P = .064). Additionally, no echocardiographic evidence of transient cardiotoxicity was found. The left ventricular ejection fraction (LVEF) also did not show any significant changes (ΔLVEF, -2.17%; P = .15). Magnetic resonance imaging confirmed no changes in structure or function (ΔLVEF, -2.6%; P = .54) and extracellular volume fraction (Δ = 2%; P = .46). The serum biomarker levels also did not change significantly over time. CONCLUSION: We did not observe cardiotoxicity from bortezomib-based chemotherapy despite very intensive evaluation with multiple modalities. Neither cumulative nor transient alterations were found in our metrics, suggesting that bortezomib is safe from a cardiovascular standpoint for patients free of cardiovascular disease.

Current Concepts of Cardiac Amyloidosis: Diagnosis, Clinical Management, and the Need for Collaboration.

Cardiac amyloidosis is a complex and vexing clinical condition that requires a high degree of suspicion for the diagnosis with a substantial amount of discipline to discern the extent of disease and the best available therapy. There is a complex interplay between multiple organ systems, and the clinical presentation may involve a myriad of confusing clinical symptoms. The diagnosis of cardiac amyloidosis can be confirmed with a combination of physical findings, cardiac biomarkers, noninvasive testing, and, if necessary, myocardial biopsy. Genetic testing is critical to establish the type of amyloidosis.