Anthracyclines are a group of potent antitumour agents and cardiotoxicity is an important factor limiting their therapeutic effectiveness. Although cardiomyopathy is the most widely recognized type of cardiotoxic reaction, early arrhythmia following anthracycline administration may be of clinical significance as well. We report a case of ventricular tachycardia causing cardiac arrest in a female treated with doxorubicin as adjuvant therapy of breast cancer. Due to recurrence of the arrhythmia and a desire to continue chemotherapy, an automatic cardioverter-defibrillator was implanted with excellent effect.