High-dose melphalan and autologous peripheral blood stem cell transplantation in patients with AL amyloidosis and cardiac defibrillators.

Cardiac deposition of misfolded light chains is the leading cause of morbidity and mortality in patients with immunoglobulin (AL) amyloidosis. Cardiac defibrillators can be used in the management of patients with advanced cardiac amyloidosis, but data concerning the use of these devices in patients undergoing treatment with high-dose melphalan followed by autologous peripheral blood stem cell transplantation (HDM/SCT) is limited. Herein we describe a single-institution experience of HDM/SCT in 15 patients with cardiac defibrillators. During the peri-transplant period, five of these patients (33%) had detectable cardiac arrhythmias and two patients (13%) had implantable cardiac defibrillator (ICD) discharges. Thirteen of the 14 evaluable patients (93%) achieved at least a partial hematologic response. Transplant-related mortality was 6.7% and median overall survival was 40.8 months, with multiple patients achieving an overall survival of >10 years. These data highlight the feasibility of HDM/SCT in patients with an ICD due to advanced cardiac AL amyloidosis, but highlight the need for additional research to appropriately determine which patients will benefit from this aggressive therapy.