Paroxysmal atrial fibrillation after high-dose melphalan in five patients autotransplanted with blood progenitor cells.

Among the drugs used in conditioning regimens for stem cell transplantation, high-dose melphalan (HDM) plays an important role for both its strong myeloablative effect and for its favourable dose-response ratio. Here we report five cases of high frequency atrial fibrillation (AF) developing after HDM. Duration of the arrhythmia was always very short, beginning at variable intervals after the administration of HDM, in the absence of other factors potentially able to trigger AF. In all patients sinus rhythm was restored within 72 h and the follow-up did not show any cardiac damage. To the best of our knowledge, this side-effect has never been reported to occur after HDM.