Recurrence of paroxysmal atrial fibrillation after cryoisolation of the pulmonary veins. Is a "redo" procedure using the cryoballoon useful?

BACKGROUND: Pulmonary vein (PV) isolation with the cryoballoon technique is an effective and safe method to treat patients with paroxysmal atrial fibrillation (AF). However, the optimal treatment strategy for patients with recurrences after this ablation is unclear. AIMS: The aim of this single centre study was to evaluate the efficacy and safety of a "redo" procedure using the cryoballoon in this patient cohort. The secondary study objectives were to determine the rate of reconduction for individual PVs of the patients undergoing "redo" ablation and potential predictors of persistent PV isolation (PVI). METHODS: Between April 2006 and September 2009, all patients with paroxysmal AF recurrences after cryoballoon ablation a "redo" ablation with the cryoballoon was offered. PV conduction was determined and cryoapplications were performed in all reconnected PVs. Every 3 months, 7-day Holter ECG, symptom-driven transtelephonic ECG recordings, and questionnaires were collected for 12 months. RESULTS: Forty-seven patients underwent "redo" cryoballoon ablation. In all these patients, at least one PV with reconduction was found. Recurrent conduction was documented in 63 % of the left superior PV, 56 % of the left inferior PV, 43 % of the right superior PV, and 56 % of the right inferior PV. In 28 of the 47 patients (60 %), no AF recurrence was detectable during the 12-month follow-up (after 3 months blanking period). Rate of severe complications was low and not significantly different from that of the initial ablations. CONCLUSION: "Redo" ablation using cryoballoon technology may be an effective and safe method to treat patients with recurrence of paroxysmal AF after cryoballoon PVI.

Incidence and rate characteristics of atrial tachyarrhythmias in patients with a dual chamber defibrillator.

Atrial tachyarrhythmias play an important role in the treatment of patients with malignant ventricular tachyarrhythmias not only with respect to inappropriate discharges but also to left ventricular function and stroke risk. A combined dual chamber defibrillator provides separate therapies for atrial and ventricular tachyarrhythmias. To assess the incidence of atrial tachyarrhythmias in patients with this dual chamber implantable defibrillator, 40 patients with ventricular tachyarrhythmias and concomitant atrial tachyarrhythmias and/or AV conduction disturbances were included in a prospective study. During a mean follow-up of 25 +/- 11 months, 26 of 40 patients had a total of 1,430 recurrences of atrial tachyarrhythmias. The vast majority of the atrial tachyarrhythmias with regular atrial cycles had a mean median atrial cycle length of 235 +/- 37 ms and a mean duration of 34 +/- 144 minutes. Atrial tachyarrhythmias with irregular atrial cycles exhibited a median atrial cycle length of 198 +/- 31 ms and had a mean duration of 246 +/- 1,264 minutes. In addition, 67% of 375 tachyarrhythmias, in which the median ventricular cycle length during the ongoing episode could be documented, had a ventricular rate <100 beats/min. Continuous atrial arrhythmia detection with a dual chamber ICD reveals a high incidence of atrial tachyarrhythmias with a predominantly short duration of paroxysmal recurrences <1 hour in the vast majority of episodes.