High dose ara-C therapy induced bradycardia in an acute myeloid leukemia patient with inv (16)(p13q22)

A 20-year-old Japanese woman was diagnosed as having acute myeloid leukemia with inv(16)(p13 q22). She achieved complete remission (CR) after treatment with a standard dose of cytarabine(ara-C) and idarubicin. She received high dose ara-C and etoposide for the 2nd consolidation chemotherapy. On the 5th fraction of high dose ara-C, her heart rate dropped to 52/minute and returned to 72/minute after the cessation of ara-C. After achieving informed consent, we gave her another course of high dose ara-C, which once again resulted in a decreased heart rate. This suggests that the administration of high dose ara-C could cause bradycardia.