title: Predictability of lesion durability for AF ablation using phased radiofrequency: Power, temperature, and duration impact creation of transmural lesions.
abstract: Long-term clinical outcomes for atrial fibrillation ablation depend on the creation of durable transmural lesions during pulmonary vein isolation and on substrate modification. Focal conventional radiofrequency (RF) ablation studies have demonstrated that tissue temperature and power are important factors for lesion formation. However, the impact and predictability of temperature and power on contiguous, transmural lesion formation with a phased RF system has not been described.
  
  
  
  The purpose of this study was to determine the sensitivity, specificity, and predictability of power and temperature to create contiguous, transmural lesions with the temperature-controlled, multielectrode phased RF PVAC GOLD catheter.
  
  
  
  Single ablations with the PVAC GOLD catheter were performed in the superior vena cava of 22 pigs. Ablations from 198 PVAC GOLD electrodes were evaluated by gross examination and histopathology for lesion transmurality and contiguity. Lesions were compared to temperature and power data from the phased RF GENius generator. Effective contact was defined as electrodes with a temperature of ≥50°C and a power of ≥3 W.
  
  
  
  Eighty-five percent (168 of 198) of the lesions were transmural and 79% (106 of 134) were contiguous. Electrode analysis showed that >30 seconds of effective contact identified transmural lesions with 85% sensitivity (95% confidence interval [CI] 78%-89%), 93% specificity (95% CI 76%-99%), and 99% positive predictive value (95% CI 94%-100%). Sensitivity for lesion contiguity was 95% (95% CI 89%-98%), with 62% specificity (95% CI 42%-78%) and 90% positive predictive value (95% CI 83%-95%). No char or coagulum was observed on the catheter or tissue.
  
  
  
  PVAC GOLD safely, effectively, and predictably creates transmural and contiguous lesions.
authors.affiliation: L'Institut de Rythmologie et Modélisation Cardiaque (LIRYC) Hôpital Cardiologique du Haut-Lévêque, University of Bordeaux, Bordeaux, France. Electronic address: meleze.hocini@chu-bordeaux.fr.
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.affiliation: Medtronic, Inc., Minneapolis, Minnesota.
authors.forename: Cathy
authors.initials: C
authors.lastname: Condie
authors.affiliation: Medtronic, Inc., Minneapolis, Minnesota.
authors.forename: Mark T
authors.initials: MT
authors.lastname: Stewart
authors.affiliation: Medtronic, Inc., Minneapolis, Minnesota.
authors.forename: Nicole
authors.initials: N
authors.lastname: Kirchhof
authors.affiliation: Medtronic, Inc., Minneapolis, Minnesota.
authors.forename: Jason D
authors.initials: JD
authors.lastname: Foell
mesh_terms: D000818:Animals; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D004566:Electrodes / Q000592:standards; D006329:Heart Conduction System / Q000528:radiation effects; D006358:Hot Temperature / Q000009:adverse effects*; D007431:Intraoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D008953:Models, Anatomic; D011667:Pulmonary Veins / Q000601:surgery*; D020379:Risk Adjustment / Q000379:methods; D013552:Swine; D013997:Time Factors
keywords: Ablation; Atrial fibrillation; Contiguous; Lesion; PVAC GOLD; Pulmonary vein isolation; Radiofrequency; Transmural