Eighteen pediatric oncology or bone marrow transplant (BMT) survivors who had liver iron content of >12 mg/g dry weight also underwent Cardiac MR (CMR) to quantify cardiac iron content. Despite high transfused packed red blood cell volumes (mean 383 ml/kg) patients all had cardiac T2* relaxation times in normal ranges (T2* relaxation time mean 35.1 msec ± 7.1 [normal >20 msec]).