Sustained improvement in cardiac function with persistent amyloid deposition in a patient with multiple myeloma-associated cardiac amyloidosis treated with bortezomib

We describe the case of a 62-year-old man with biopsy-proven cardiac involvement of multiple myeloma-associated immunoglobulin light-chain amyloidosis, whose cardiac function improved after bortezomib therapy. Angiotensin-converting enzyme inhibitors and diuretics were initially administered, resulting in improvement of heart failure symptoms and disappearance of nonsustained ventricular tachycardia. To reduce production of amyloidogenic precursor proteins, bortezomib therapy combined with dexamethasone was subsequently started. Hematological responses were rapid and adverse events were manageable. At present, 15 months after the treatment, cardiac function of the patient showed sustained improvement, although follow-up biopsy specimens showed persistent amyloid deposition in the myocardium corresponding to echocardiogram results demonstrating no reduction in ventricular wall thickness.