Supraventricular tachycardia has several clinical manifestations with one of the most dangerous – tachycardiomyopathy, which directs clinical footsteps towards catheter ablation rather than pharmacotherapy. Both accessory pathway and focal atrial tachycardia alone are listed as risk factors for tachycardiomyopathy development. We present a case of an 17-years old adolescent with atrioventricular reentrant tachycardia and focal atrial tachycardia, which resulted in arrythmia related cardiomyopathy occurrence and were successfully treated with radiofrequency ablation during one procedure. All of the arrythmia and heart failure related symptoms resolved within weeks after the catheter ablation, which confirmed these two arrythmia as the reason for heart remodelling. Rapid symptoms onset requires fast proceeding and electrophysiological study (EPS) with potential catheter ablation should not be postponed.