Spatial correction improves accuracy of catheter positioning during ablation of premature ventricular contractions: differences between ventricular outflow tracts and other localizations.

BACKGROUND: Hybrid activation mapping is a novel tool to correct for spatial displacement of the mapping catheter due to asymmetrical contraction of myocardium during premature ventricular contractions (PVC). The aim of this study is to describe and improve our understanding of spatial displacement during PVC mapping as well as options for correction using hybrid activation mapping. METHODS AND RESULTS: We analyzed 5798 hybrid mapping points in 40 acquired hybrid maps of 22 consecutive patients (age 63 ± 16 years, 45% female) treated for premature ventricular contractions (PVCs). Median PVC-coupling interval was 552 ms (IQR 83 ms). Spatial displacement was determined by measuring the dislocation of the catheter tip during PVC compared to the preceding sinus beat. Mean spatial displacement was 3.8 ± 1.5 mm for all maps. The displacement was 1.3 ± 0.4 mm larger for PVCs with non-outflow-tract origin compared to PVCs originating from the ventricular outflow tracts (RVOT/LVOT; p = 0.045). Demographic parameters, PVC-coupling-interval and chamber of origin had no significant influence on the extent of spatial displacement. CONCLUSION: Ectopic activation of the ventricular myocardium during PVCs results in spatial displacement of mapping points that is significantly larger for PVCs with non-outflow-tract origin. The correction for spatial displacement may improve accuracy of radiofrequency current (RFC)-application in catheter ablation of PVCs.

[Radiofrequency current or cryoballoon for ablation of atrial fibrillation? : Hot or cold?] / Hochfrequenzstrom oder Cryoballon für die Ablation von Vorhofflimmern? : "Hot or cold?".

Atrial fibrillation (AF) is the most common form of cardiac arrhythmia. The aim of therapy in symptomatic patients is the establishment of a stable sinus rhythm (SR). Catheter ablation with isolation of the pulmonary veins is the essential component of all forms of ablation therapy and provides the most effective treatment option. The most frequently used technologies for pulmonary vein isolation (PVI) are radiofrequency current (RFC)-based and cryoballoon (CB)-guided ablation. Irrespective of the simplification of PVI, CB ablation is characterized by a short learning curve and short procedural times and demonstrated non-inferiority with respect to safety and efficacy when directly compared to RFC ablation for the treatment of patients with paroxysmal AF; however, the clinical outcome in patients with persistent AF is often insufficient when performing pulmonary vein isolation (PVI) alone for stabilization of SR. Differentiated RFC ablation is the treatment of choice when performing additional ablation strategies beyond PVI in order to improve clinical results with freedom from arrhythmia recurrence.