Contact-force guided radiofrequency vs. second-generation balloon cryotherapy for pulmonary vein isolation in patients with paroxysmal atrial fibrillation-a prospective evaluation.

AIMS: In the setting of paroxysmal atrial fibrillation (AF), there are no available data comparing the mid-term outcome of patients undergoing pulmonary vein isolation (PVI) catheter ablation using contact-force (CF)-guided radiofrequency (RF) vs. second-generation balloon cryotherapy. METHODS AND RESULTS: Prospective single-centre evaluation, carried out from March 2011 to February 2013, comparing CF radiofrequency (Thermocool(®) SmartTouch™, Biosense Webster, Inc.) (CF group) with cryoballoon ablation (Arctic Front Advance™ 28 mm cryoballoon, Medtronic, Inc.) (CB group), in regards to procedural safety and efficacy, as well as recurrence at 12 months. Overall, 150 consecutive patients were enrolled (75 in each group). The characteristics of patients of both the groups were similar (61.2 ± 9.9 years, women 25.3%, mean AF duration 4.1 ± 4.0 years, mean CHA2DS2-VASc score 1.4 ± 1.3, mean HAS-BLED 1.4 ± 0.6). Duration of the procedure was significantly lower in the CF group (110.7 ± 32.5 vs. 134.5 ± 48.3 min, P = 0.001), with a lower duration of fluoroscopy (21.5 ± 8.5 vs. 25.3 ± 9.9 min, P = 0.017) and X-ray exposure (4748 ± 2411 cGy cm² vs. 7734 ± 5361 cGy cm², P = 0.001). In contrast, no significant difference was found regarding significant procedural complication (2.7 vs. 1.3% in CF and CB groups, respectively; P = 0.56), and PVI was eventually achieved in all cases. At 12 months, AF recurrence occurred in 11 patients (14.7%) in the CB group and in 9 patients (12.0%) in the CF group (HR = 1.20 95% CI 0.50-2.90; log rank P = 0.682). CONCLUSIONS: Our preliminary findings suggest that CF-guided radiofrequency and cryotherapy present very similar performances in the setting of paroxysmal AF catheter ablation.

Rivaroxaban and dabigatran in patients undergoing catheter ablation of atrial fibrillation.

AIMS: The recent availability of the novel oral anticoagulants (NOACs) may have led to a change in the anticoagulation regimens of patients referred to catheter ablation of atrial fibrillation (AF). Preliminary data exist concerning dabigatran, but information regarding the safety and efficacy of rivaroxaban in this setting is currently scarce. METHODS AND RESULTS: Of the 556 consecutive eligible patients (age 61.0 ± 9.6; 74.6% men; 61.2% paroxysmal AF) undergoing AF catheter ablation in our centre (October 2012 to September 2013) and enroled in a systematic standardized 30-day follow-up period: 192 patients were under vitamin K antagonists (VKAs), 188 under rivaroxaban, and 176 under dabigatran. Peri-procedural mortality and significant systemic or pulmonary thromboembolism (efficacy outcome), as well as bleeding events (safety outcome) during the 30 days following the ablation were evaluated according to anticoagulation regimen. During a 12-month time interval, the use of the NOACs in this population rose from <10 to 70%. Overall, the rate of events was low with no significant differences regarding: thrombo-embolic events in 1.3% (VKA 2.1%; rivaroxaban 1.1%; dabigatran 0.6%; P = 0.410); major bleeding in 2.3% (VKA 4.2%; rivaroxaban 1.6%; dabigatran 1.1%; P = 0.112), and minor bleeding 1.4% (VKA 2.1%; rivaroxaban 1.6%; dabigatran 0.6%; P = 0.464). No fatal events were observed. CONCLUSION: The use of the NOAC in patients undergoing catheter ablation of AF has rapidly evolved (seven-fold) over 1 year. These preliminary data suggest that rivaroxaban and dabigatran in the setting of catheter ablation of AF are efficient and safe, compared with the traditional VKA.

Real-time assessment of pulmonary vein disconnection during cryoablation of atrial fibrillation: can it be 'achieved' in almost all cases?

AIM: Real-time assessment of pulmonary vein (PV) disconnection is possible using an inner circular mapping catheter during cryoablation of atrial fibrillation (AF). However, it has been recently demonstrated that such continuous monitoring may only be possible in <50% of PVs. We hypothesized that a stepwise mapping approach, including pacing manoeuvres, could optimize monitoring of real-time PV disconnection during ablation. METHODS AND RESULTS: Single-centre, prospective observational study (NCT01843465) including 34 consecutive eligible patients (128 PVs) undergoing a first procedure of cryoballoon ablation of AF using the Artic Front Advance(®) 28 mm catheter and a 20 mm diameter Achieve(®) catheter (AC) in all cases. Monitoring of real-time entrance block was possible, when AC was maintained in the standard position (distal to the tip of the Artic Front Advance(®) catheter) in 47 (36.7%) PVs. In an additional 63 cases (49.2%), such monitoring was possible after moving AC to a more proximal position and using different torqueing movements. Finally, using supplemental systematic pacing manoeuvres to test exit block, real-time assessment of PV disconnection was possible in 15 (11.7%) more PVs. Overall, real-time assessment of PV disconnection was possible in 97.7% of cases, after a mean duration of 48.6 ± 33.0 s. CONCLUSION: Our results suggest that optimal use of the AC, with a systematic stepwise mapping approach, may dramatically improve the real-time monitoring of PV disconnection during AF cryoablation.