Abstract Background Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Tools and techniques used for confirmation of PVI vary greatly, and it is unclear whether the use of any particular combination of tools and techniques provides greater sensitivity for identifying gaps periprocedurally. A high-density mapping catheter enabling simultaneous recording of adjacent bipolar EGMs in two directions is now available in multiple geographies, and it has been suggested that this technology may provide improved sensitivity for gap identification. Purpose To identify trends in the incidence of gaps identified in de novo PVI lines using three diagnostic catheter technologies, which may be suggestive of improved sensitivity for gap identification. Methods Self-reported procedural data was prospectively collected in de novo atrial fibrillation ablation cases utilizing one of three technologies to confirm PVI: 10-pole circular mapping catheter (CMC10), 20-pole circular mapping catheter (CMC20), and Advisor HD Grid catheter (HD Grid). Techniques for PVI confirmation were analyzed for each group, and the incidence and location of gaps identified by each technology was quantified. Results Data was collected in 99 cases across 11 centers in Europe and the United States. PVI was confirmed via entrance and/or exit block in all cases. CMC10 was utilized in 30 cases, CMC20 in 36, and HD Grid in 33. Use of adenosine varied across groups (CMC10: 6.7%; CMC20: 86.1%; HD Grid: 41.7%), as did application of a waiting period (CMC10: 96.7%; CMC20: 2.8%; HD Grid: 11.1%). Gaps were identified in in 36.7%, 38.9%, and 81.8% of cases using CMC10, CMC20, and HD Grid, respectively. HD Grid identified significantly more gaps than the other two technologies (p = 0.015), identifying an average of 49.0% and 139.1% more gaps per patient than CMC20 and CMC10, respectively (HD Grid: 2.15/patient; CMC20: 1.44/patient; CMC10: 0.9/patient). The location and incidence of gaps identified by each technology is shown in Figure 1. Conclusions Significantly more gaps were identified by the Advisor HD Grid catheter, as compared to a 10-pole or 20-pole circular mapping catheter. While this does not represent a direct comparison of the sensitivity for identification of gaps across these three technologies, and results could be impacted by other factors (e.g., operator, ablation technique, PVI confirmation technique, etc.), the strong trend toward an increased number of gaps identified with the HD Grid is striking. This may warrant further study including direct comparison of gap identification across technologies, and the resulting impact on long-term clinical outcomes when these additional gaps are ablated during the index procedure. Abstract Figure.

Objectives The purpose of this study was to investigate the efficacy safety of the novel cryoballoon device ( Arctic Front, Cryocath, Quebec, Canada).Background Antral pulmonary vein (PV) ablation with radiofrequency energy is widely used as a strategy for catheter ablation of paroxysmal atrial fibrillation (PAF). A novel double lumen cryoballoon catheter was designed for circumferential pulmonary vein isolation (PVI) with the cryoablation technique.Methods We consecutively enrolled 346 patients with symptomatic, drug refractory paroxysmal (n=293) or persistent ( n=53) atrial fibrillation (AF). In all patients, PVI of all targeted PVs was the therapeutic aim. The primary end points of this nonrandomized study were: 1) acute isolation rate of targeted PV; and 2) first electrocardiogram-documented recurrence of AF. The secondary end point was occurrence of PV stenosis or atrio-esophageal fistula.Results The 1,360 of 1,403 PVs (97%) were targeted with balloons or balloons in combination with the use of Freezor Max ( Cryocath). We found that ablation with the cryoballoon resulted in maintenance of sinus rhythm in 74% of patients with PAF and 42% of patients with persistent AF. No PV narrowing occurred. The most frequent complication was right phrenic nerve palsy observed during cryoballoon ablation at the right superior PV.Conclusions Pulmonary vein isolation with a new cryoballoon technique is feasible. Sinus rhythm can be maintained in the majority of patients with PAF by circumferential PVI using a cryoballoon ablation system. Cryoablation was less effective in patients with persistent AF than in patients with PAF.

Aims: This study investigates the influence of cardiac resynchronisation therapy (CRT) on sleep disordered breathing (SDB) in patients with severe heart failure (HF).Methods and results: Seventy-seven patients with HF (19 fernales; 62.6 +/- 10 years) eligible for CRT were screened for presence, type, and severity of SDB before and after CRT initiation (5.3 +/- 3 months) using cardiorespiratory polygraphy. NYHA class, frequency of nycturia, cardiopulmonary exercise, 6-minute walking test results, and echocardiography parameters were obtained at baseline and follow-up.Central sleep apnoea (CSA) was documented in 36 (47%), obstructive sleep apnoea (OSA) in 26 (34%), and no SDB in 15 (19%) patients. CRT improved clinical and haemodynamic parameters. SDB parameters improved in CSA patients only (apnoea hypopnoea index: 31.2 +/- 15.5 to 17.3 +/- 13.7/h, p < 0.001; SaOmin: 81.8 +/- 6.6 to 84.8 +/- 3.3%, p=0.02, desaturation: 6.5 +/- 2.3 to 5.5 +/- 0.8%, p=0.004). Daytime capillary pCO(2) was significantly lower in CSA patients compared to those without SDB with a trend towards increase with CRT (35.5 +/- 4.2 to 37.9 +/- 5.7 mm, Hg, ns). After classifyirig short term clinical and haemodynamic CRT effects, improved SDB parameters in CSA occurred in responders only.Conclusions: In patients with severe HF eligible for CRT, CSA is common and can be influenced by CRT, this improvement depends on good clinical and haemodynamic response to CRT. (c) 2007 European Society of Cardiology. Published by Elsevier B.V All rights reserved.