Experience with radiofrequency catheter ablation of fascicular tachycardia.

OBJECTIVE To report experience with radiofrequency catheter ablation of fascicular tachycardia including two cases of the rare type of this arrhythmia which arises from the anterior fascicle of the left bundle branch. DESIGN Review of results of radiofrequency ablation in nine consecutive patients presenting with fascicular tachycardia. SETTING Regional cardiac centre. INTERVENTION Percutaneous radiofrequency catheter ablation, performed between 1993 and 1996. RESULTS Radiofrequency ablation was successful in both patients with tachycardia arising from the anterior fascicle and in six of the seven patients with tachycardia arising from the anterior fascicle and in six of the seven patients with tachycardias arising from the posterior fascicle. Notable differences in the "right bundle branch block" configuration of lead V1 during tachycardia between patients were observed. One patient with incessant tachycardia had marked impairment of ventricular function which returned to normal after ablation. CONCLUSIONS Radiofrequency ablation is effective in both anterior and posterior fascicular tachycardias. The arrhythmia can cause reversible impairment of ventricular function.