Background and objective: As has recently been discovered, paroxysmal atrial fibrillation (PAF) can be induced by focal extrasystoles or tachycardia. This raises the question of whether this form of atrial fibrillation can be cured by high-frequency catheter ablation of the focal trigger.
Patients and methods: Seven men and eleven women (mean age 45.6 +/- 11 years) with severe symptoms and treatment-resistant PAF underwent electrophysiological tests with the aim of high-frequency catheter ablation, if long-term ECG monitoring had demonstrated frequent atrial extrasystoles or tachycardia as pointer to a focal origin. Ablation was performed at the point of earliest excitation after the origin of the ectopic focus had been localized. The end-point was reached if the atrial ectopic rhythm had ceased for more than 60 min.
Results: In 18 of the 20 patients an ectopic focus was found and successfully ablated (1 in the superior vena cava, 3 in the right atrium and 16 in a pulmonary vein). Atrial ectopic beats recurred within 24 hours of ablation in 6 of the 14 patients with a pulmonary vein focus: a second focus was found in two, re-emergence of the original focus in two, no re-investigation in another two. 13 of the 18 patients have had no further symptoms after a mean follow-up of 11 months without anti-arrhythmia treatment.
Conclusion: The results indicate that focally induced paroxysmal atrial fibrillation can be cured by locally applied high-frequency ablation.