Balloon cryoablation of the pulmonary veins with additional segmental isolation if necessary, is a good approach for patients presenting with paroxysmal AF, showing a significant reduction in AF burden after a single procedure. The major complication seems to be phrenic nerve paralysis after ablation of the right superior PV, but this is potentially reversible over several months.

AimsPulmonary vein isolation (PVI) with cryoenergy delivered through a balloon is a new approach in the treatment of atrial fibrillation (AF), but long-term follow-up is lacking. The aim of this study was to provide insight in the success rate and the incidence of recurrences.Methods and resultsPatients with symptomatic AF despite anti-arrhythmic drugs (AADs) were treated with cryoballoon PVI. Daily transtelephonic ECG monitoring, 24 h Holter-ECG, and an arrhythmia-focused questionnaire were used to document AF. One hundred and forty-one patients completed a follow-up of 457 ± 252 days. Before ablation, Holter-ECG showed AF in 45%, including 16% continuous AF throughout the recording. Event recording revealed a median AF burden of 26%. The questionnaire showed a median of weekly AF complaints lasting for hours. All but one patient had successful PVI with a single procedure. After ablation, AF (defined as lasting for more than 30 s) was seen in 11% of Holter-ECGs, with 1% continuous AF. The event recording showed an AF burden of 9%. The median patient reported no more AF-related symptoms. Recurrence during the first 3 months was predictive for later recurrence. A second procedure was performed in 24 patients. The freedom of AF was 59% without AADs after 1,2 procedures. Four right phrenic nerve paralyses occurred, all resolving within 6 months. No PV stenoses were observed.ConclusionPulmonary vein isolation with a cryothermal balloon is an effective treatment for paroxysmal AF, resulting in a clinical success rate comparable to studies involving radiofrequency ablation. Temporary right phrenic nerve paralysis is the most important complication.

BackgroundRadiofrequency (RF) catheter ablation for atrioventricular nodal reentrant tachycardia (AVNRT) is highly successful but carries a risk for inadvertent atrioventricular block. Cryoablation (cryo) has the potential to assess the safety of a site before the energy is applied.PurposeThe aim of this study was to evaluate the long-term efficacy and safety of cryothermal ablation in a large series of patients and compare it to RF.MethodsAll consecutive routinely performed AVNRT ablations from our centre between 1999 and 2007 were retrospectively analysed.ResultsIn total, 274 patients were elegible: 150 cryoablations and 124 RF. Overall procedural success was 96% (262/274), and equal in both groups, but nine patients were crossed to another arm. Mean fluoroscopy time was longer in the group treated with RF (27 ± 22 min vs. cryo 19 ± 15 min; p = 0.002). Mean procedure time was not different (RF 138 ± 71 min vs. cryo 146 ± 60 min). A permanent pacemaker was necessary in two RF patients. The questionnaire revealed a high incidence of late arrhythmia related symptoms (48%), similar in both groups, with improved perceived quality of life. The number of redo procedures for AVNRT over 4.3 ± 2.5-years follow-up was not statistically different (11% after cryo and 5% after RF).ConclusionsOur data confirm that cryo and RF ablation with 4-mm tip catheters for AVNRT are equally effective, even after long-term follow-up.

Aims Steering soft, flexible catheters using an external magnetic field could have advantages for heart catheterization, especially for therapy of tachyarrhythmias. Our aims were to assess the feasibility of magnetic navigation to Koch's triangle and reliable ablation of atrioventricular nodal re-entry tachycardia (AVNRT) with a magnetic catheter. Methods and results Consecutive patients with AVNRT were mapped and ablated with a magnetically enabled catheter (Helios I or II), with, respectively, one and three magnets at the tip. The catheter was remotely advanced with the Cardiodrive TM system and orientated with the Navigant TM control system. After initial positioning with the external magnets, adjustment was made in 58 steps. Success rates, procedure, and fluoroscopy times were analysed, and compared with a local contemporary series of conventional AVNRT ablations. Magnetic navigation was feasible in all 20 patients. Targets were easily reached. Catheters remained stable in position during accelerated junctional rhythms. Ablation was successful in 18/20 procedures (90%). No significant complications occurred. Median patient fluoroscopy time was 12 min, median physician fluoroscopy time was 4 min. Fluoroscopy times tended to be shorter than that in the conventionally treated group. Procedure duration decreased significantly over time, median procedure time was similar to that in the conventional group. Conclusion AVNRT can be successfully mapped and ablated using magnetic navigation. A learning curve was evident, unrelated to catheter type, but to increasing operator experience. Physician radiation times were one-third of patient times. No complications occurred. Procedure time is comparable with that of conventional ablation.