Fludarabine and bradycardia in recipients of allogeneic stem cell transplant: a case series

Fludarabine is being increasingly used both as a chemoimmunotherapeutic agent and in conditioning regimens for stem cell transplant. ECG disturbances with this increasingly used drug have never been reported. This report describes a patient who developed bradycardia following fludarabine administration, prompting an assessment for rhythm irregularities in subsequent patients undergoing stem cell transplant using a fludarabine-based conditioning regimen. In a series of 10 patients who received fludarabine as part of their conditioning, there was a significant effect on QTc interval (mean difference 30.6 ms; P = 0.002) and heart rate (mean difference −18.9 beats/min; P = 0.003). In conclusion, caregivers need to be alert to recognize the potential for unrecognized adverse events even in frequently used drugs. Fludarabine has a potential for rhythm disturbances.