We present 14-year-old girl with permanent junctional reciprocating tachycardia which was refractory to medicamentous therapy, who also had dilated cardiomyopathy. She underwent successful radiofrequent catheter ablation of accessory pathway after wich the histologic changes in the myocardium were observed in the form of compensatory hypertrophy of cardiac muscle (cardiac remodelling). The question of cause and consequence appeared: whether the arrhythmia is a consequence of dilated cardiomyopathy, or it is tachycardia- induced cardiomyopathy. This particular issue is discussed in this article. Based on the diagnostic procedure and complete recovery of myocardium after catheter ablation of accessory pathway, it is obvious that the tachycardia was due to tachicardiomyopathy, i.e. cardiomyopathy caused by permanent reciprocating junctional tachycardia.