Light chain (AL) cardiac amyloidosis is a disease where abnormal proteins are deposited in the heart tissue, commonly resulting in elevated myocardial stiffness. In cases with poor prognosis, autologous hematopoietic stem cell transplantation is used as a therapy. However, organ response monitoring is currently limited and challenging. The goal of this study is to evaluate the feasibility of using cardiac magnetic resonance elastography (MRE) to monitor changes in left ventricular (LV) myocardial stiffness after stem cell transplantation for treatment of AL amyloidosis. MRE detected a statistically significant (p=0.007) decrease in LV stiffness (mean decrease: 1.6±0.7 kPa, 17.0±7.4%) post therapy.