2-year outcomes of phased radiofrequency ablation for atrial fibrillation with the second-generation PVAC Gold ablation catheter.

PURPOSE: The second-generation multi-electrode catheter, PVAC Gold, was designed to improve the safe delivery of phased radiofrequency energy using a "single shot" approach for pulmonary vein isolation (PVI), while retaining efficacy. This large registry presents long-term performance in a daily practice setting. METHODS: A total of 1011 patients undergoing first time ablation for atrial fibrillation (AF) using PVAC Gold were included, 639 patients with PVI for paroxysmal AF (PAF PVI) and 372 patients with persistent or long-standing persistent AF, divided into 175 patients receiving PVI only (PersAF PVI) and 197 patients receiving PVI with additional substrate ablation (PersAF PVI +). RESULTS: At 24-month follow-up, single procedure freedom from atrial tachyarrhythmia (ATA) was 58% (368/639) in the PAF PVI group, 44% (77/175) in the PersAF PVI group, and 29% (57/197) in the PersAF PVI + group. Allowing one repeat procedure in 33% of patients, 76%, 65%, and 54% were free from ATA at 24 months, respectively. Pulmonary vein reconnection was observed in 98% of patients with recurrent arrhythmia after PVI. CONCLUSIONS: Although phased RF ablation with PVAC Gold is quick and safe, the efficacy outcomes are modest compared to current mainstream ablation strategies.

Initial experience with AcQMap catheter for treatment of persistent atrial fibrillation and atypical atrial flutter.

INTRODUCTION: The AcQMap High Resolution Imaging and Mapping System was recently introduced. This system provides 3D maps of electrical activation across an ultrasound-acquired atrial surface. METHODS: We evaluated the feasibility and the acute and short-term efficacy and safety of this novel system for ablation of persistent atrial fibrillation (AF) and atypical atrial flutter. RESULTS: A total of 21 consecutive patients (age (mean ± standard deviation) 62 ± 8 years, 23% female) underwent catheter ablation with the use of the AcQMap System. Fourteen patients (67%) were treated for persistent AF and 7 patients (33%) for atypical atrial flutter. Eighteen patients (86%) had undergone at least one prior ablation procedure. Acute success, defined as sinus rhythm without the ability to provoke the clinical arrhythmia, was achieved in 17 patients (81%). At 12 months, 4 patients treated for persistent AF (29%) and 4 patients treated for atypical flutter (57%) remained in sinus rhythm. Complications included hemiparesis, for which intra-arterial thrombolysis was given with subsequent good clinical outcome (n = 1), and complete atrioventricular block, for which a permanent pacemaker was implanted (n = 2). No major complications attributable to the mapping system occurred. CONCLUSION: The AcQMap System is able to provide fast, high-resolution activation maps of persistent AF and atypical atrial flutter. Despite a high acute success rate, the recurrence rate of persistent AF was relatively high. This may be due to the selection of the patients with therapy-resistant arrhythmias and limited experience in the optimal use of this mapping system that is still under development.

High-density versus low-density mapping in ablation of atypical atrial flutter.

PURPOSE: Ablation of atypical atrial flutter (AAFL) can be challenging. High-density (HD) mapping of ablation targets may potentially increase procedural success and freedom from recurrent AAFL. The objective of the present study was to explore whether employing HD mapping leads to a more favorable outcome in ablation of AAFL. METHODS: We compared baseline and procedural characteristics, procedural success, safety and outcome of mapping and ablation of atypical flutter in three groups. (1) HD Grid catheter + the high-density electroanatomical mapping (EAM) system EnSite Precision; (2) standard 10-pole circular mapping catheter (CMC) + EnSite Precision; (3) CMC + the low-density EnSite Velocity EAM. Voltage and propagation maps were constructed. RESULTS: Mapping of 142 AAFL in 82 patients was performed. Acute ablation success was 78%, 68%, and 51% in groups 1, 2, and 3 (p = 0.037 between group 1 and 3, non-significant between groups otherwise). Moreover, 8%, 27%, and 36% of flutters were unmappable in groups 1, 2, and 3, respectively (p < 0.05 between group 1 and both groups 2 and 3). AAFL recurrence at 1-year FU was 26%, 36%, and 62% in groups 1, 2, and 3 (p = 0.007 between groups 1 and 3, p = 0.05 between groups 2 and 3). AAFL-free survival was significantly higher in patients mapped with Precision than with Velocity (p = 0.011). No strokes or mortality occurred within 30 days. CONCLUSIONS: Acute procedural success of ablation of atypical atrial flutter is higher and the number of unmappable flutters is lower using the HD Grid mapping catheter in combination with the high-density EnSite Precision system, as compared to a decapolar circular mapping catheter and the low-density EnSite Velocity EAM system. This may lead to increased freedom from recurrent AAFL at 1 year. HD mapping is safe.

Acute success and safety of the second-generation PVAC GOLD phased RF ablation catheter for atrial fibrillation.

PURPOSE: The second-generation multi-electrode catheter, pulmonary vein ablation catheter (PVAC) GOLD, was designed to improve the delivery of phased radiofrequency energy and reduce procedure times using a 'single-shot' approach for pulmonary vein isolation (PVI), while retaining efficacy and safety. This large registry presents acute success rates and safety outcomes in a daily practice setting. METHODS: A total of 1017 patients undergoing first-time ablation for atrial fibrillation (AF) using PVAC GOLD were included, 644 patients with paroxysmal AF and 373 patients with non-paroxysmal AF, divided into 175 patients receiving PVI only and 198 patients receiving PVI with additional substrate modification. RESULTS: High and comparable percentages of successful PVI could be achieved in all groups (98%, 95% and 99%; p = 0.108). The median total procedure time for all groups was 90 min [70-100]. As expected, the total procedure, ablation and fluoroscopy time were significantly longer in the PVI + substrate modification group compared with the PVI-only cases (all p < 0.001), but not between the PVI-only groups (p = 0.306, p = 0.088, p = 0.233, respectively). A total of 44 complications were observed in 43 patients (4.2%). Major complications were seen in 19 patients (1.87%) and non-major procedure-related complications were seen in 25 patients (2.46%). Complications leaving permanent sequelae were rare and occurred in only four patients (0.39%). Complications did not differ between groups (p = 0.199, p = 0.438, p = 0.240 and p = 0.465 respectively). CONCLUSION: PVAC GOLD performs successful PVI, while reducing procedure times and retaining safety for paroxysmal, persistent and long-standing persistent AF. Safety was unaffected by additional substrate modification.

Left atrial appendage closure in atrial fibrillation patients with prior major bleeding or ineligible for oral anticoagulation.

AIMS: Oral anticoagulation (OAC) reduces the ischaemic stroke risk in patients with atrial fibrillation (AF), but in turn leads to an increased risk of adverse bleeding events. Alternatively, left atrial appendage closure (LAAC) using a mechanical device might overcome these bleeding complications. However, evidence regarding LAAC in patients at high bleeding risk is scarce. This study evaluates the clinical features of AF patients with previous bleeding that underwent LAAC. METHODS: In this retrospective cohort study patients with previous major bleeding or a bleeding predisposition scheduled for transcatheter LAAC were included. The frequency and type of previous bleeding events and prevalence of bleeding and ischaemic stroke during follow-up were evaluated. RESULTS: A total of 73 patients (58% male, age 72.1 ± 7.2 years; CHA2DS2-VASc 4.5 [3.0-5.0]; HAS-BLED 4.0 [3.0-4.0]; 46% paroxysmal AF) were included. Previous bleeding occurred from intracranial (n = 50, 69%), gastro-intestinal (n = 13, 18%) or multiple (n = 16, 22%) foci. After OAC discontinuation due to bleeding, 19% suffered subsequent stroke. LAAC was successful in 96% of patients. During a median of almost 3 years' follow-up recurrent major bleeding occurred in 4 patients (5.5%) despite OAC discontinuation in 93.2%. A total of 6 ischaemic strokes were observed, resulting in an annualised stroke rate of 2.9% compared to a calculated expected stroke rate of 6.7%. CONCLUSIONS: Percutaneous LAAC may provide an alternative strategy to long-term OAC therapy in AF patients with a high bleeding risk. During follow-up, both ischaemic stroke and recurrent bleeding rates were lower than expected based on the CHA2DS2-VASc and HAS-BLED scores respectively.