[Acute cardiotoxicity of anthracyclines--analysis by using Holter ECG]

To investigate the detailed acute cardiotoxicity of the anthracycline antibiotics, adriamycin (ADM) and a tetrahydropyranyl derivative (THP-ADM), Holter ECG was recorded and some of the electrocardiographic parameters were analyzed. The basic rhythm was sinus rhythm in many cases except only one case which developed intermittent atrial fibrillation after the administration of ADM. No effect on the specialized conduction system was observed in either ADM or TH-PADM. In relation to the supraventricular premature beat, no increase of the pre-existing supraventricular extrasystole and fresh appearance of the supraventricular extrasystole were observed after the administration of these drugs. On the other hand, the ventricular premature beat was tended to increase after ADM administration, and the mode of appearance of the ventricular extrasystole was very dangerous and life-threatening. For example, short-run type and R on T type ventricular extrasystole were recorded. THP-ADM induced no significant increase of the ventricular extrasystole. The developed ST-T changes were seen after the administration of these drugs, but the patients complained neither the symptoms of heart failure nor stenocardia. In conclusion. THP-ADM had less cardiotoxicity than ADM.