One-year follow-up after pulmonary vein isolation using a single mesh catheter in patients with paroxysmal atrial fibrillation

Pulmonary vein potential mapping in atrial fibrillation with high density and standard spiral (lasso) catheters: A comparative study

Background

The dominant single-shot procedure for Pulmonary Vein Isolation (PVI) is the Cryoballoon Ablation (CBA) technique using a spiral catheter (Achieve™, AC) for mapping and monitoring purposes. We hypothesized that Basket Catheters, such as the High Density Mesh Mapper (HDMM), with its high-density mapping properties, could detect Pulmonary Vein Potentials (PVPs) that the octapolar AC would not be able to identify.

Methods

Twenty-four patients (average age 61.8±10 years) with either paroxysmal or persistent atrial fibrillation (AF) (Paroxysmal AF or Persistent AF) were enrolled in the study. While the patients were in sinus rhythm, all pulmonary veins (PVs) were prospectively mapped both prior and subsequent to CBA with a 32-pole HDMM and an 8-pole AC. PVPs were recorded using both catheters, and their location was allocated to one of four PV quadrants. Then, the quadrant findings of the mapping catheters were compared.

Results

Mapping using the HDMM allowed for more precise identification of PVPs both before and after CBA compared to AC mapping. We identified an average of 83.6±4.8 PVPs in all four PVs (this means 20.9±10.5 PVPs /per single PV per patient [HDMM], 14.5±1.3 PVPs/in all four PVs and 3.6±2.7 PVPs /per single PV per patient [AC]) before ablation, thereby leading to a significant difference in the identification of PVPs per PV quadrant. Of 384 PV quadrants/24 patients analyzed, the HDMM identified PVPs in 279 and AC in only 192 quadrants (P<0.05).

Conclusion

High-density mapping with a Basket Catheter, such as the HDMM, detects PVPs that remain undetected when using the standard AC catheter in CBA procedures.

Loop Recorder Detected High Rate of Atrial Fibrillation Recurrence after a Single Balloon- or Basket-Based Ablation of Paroxysmal Atrial Fibrillation: Results of the MACPAF Study

Purpose

Pulmonary vein isolation (PVI) is an established approach to treat symptomatic non-permanent atrial fibrillation (AF). Detecting AF recurrence after PVI is important, if discontinuation of oral anticoagulation after ablation is considered.

Methods

Patients with symptomatic paroxysmal AF were enrolled in the prospective randomized mesh ablator vs. cryoballoon pulmonary vein (PV) ablation of symptomatic paroxysmal AF study, comparing efficacy and safety of the HD Mesh Ablator^® (C.R. Bard, Lowell, MA, USA) and the Arctic Front^® (Medtronic, Minneapolis, MN, USA) catheter. Rhythm status post-PVI was closely monitored for 1 year using the implantable loop recorder (ILR) Reveal XT^® (Medtronic Minneapolis, MN, USA).

Results

The study was terminated after the first interim analysis due to the inability of the HD Mesh Ablator^® to achieve the predefined primary study endpoint, an exit block of all PVs. After a 90-day blanking period, 23 (62.2%) out of 37 study patients (median 63.0 years; 41% females) had at least one episode of AF. AF recurrence was associated with AF episodes during the blanking period {hazard ratios (HR) 5.10 [95% confidence interval (CI) 1.21–21.4]; p = 0.038}, and a common left-sided PV ostium [HR 4.17 (95%CI 1.48–11.8); p = 0.039] but not with catheter type, age, gender, cardiovascular risk profile, or left atrial volume. There was a trend toward AF recurrence in patients without complete PVI of all PV (p = 0.095). Overall, 337 (59.4%) out of 566 ILR-detected episodes represented AF. Comparing patients with AF recurrence to those without, there was no difference in cognitive performance 6 months post-ablation.

Conclusion

Using an ILR, in more than 60% of all patients with paroxysmal AF, a recurrence of AF was detected within 12 months after ablation. In patients with a common PV ostium, the first generation balloon-based catheter is obviously less effective.

Clinical trials

http://Clinicaltrials.gov NCT01061931.

Comparison of circumferential pulmonary vein anatomy mapping guided by 3D mapping versus a mesh mapping catheter

OBJECTIVE

Catheter-based pulmonary vein isolation (PVI) is an established therapy for paroxysmal atrial fibrillation. The high-density mesh mapper (HDMM) guides circumferential PV-atrium isolation without the 3D electroanatomic mapping. This study aims to compare circumferential pulmonary vein (CPV) anatomy mapping between guiding by a 3D mapping system and the HDMM.

METHODS

Forty-four consecutive patients with paroxysmal atrial fibrillation were scheduled for a first procedure for PVI. A CPV ostial anatomy map guided by HDMM was set up in the CARTO system while the operator was blinded to the CARTO screen. Then CARTO-guided ipsilateral PV maps were obtained and PVI was performed. This established another set of CPV ostial anatomy maps. The differences between the two mapping images were compared and analyzed.

RESULTS

All 176 PVs in 44 patients could be mapped by both HDMM and CARTO. About 44.9% of the PV ostial anatomies were generally similar between the two different map images. The average point-to-point straight distance between the HDMM-guided map and the CARTO-guided map was 6.2 ± 1.4 mm. The area of the circumferential right PV (CRPV) in the HDMM map was larger than that in the CARTO map (P = 0.013). After a mean follow-up of 18.3 ± 4.3 months (6-24 months), 72.7% of patients (32/44) were free of atrial arrhythmia without anti-arrhythmic drugs (AADs).

CONCLUSION

Compared to the CARTO-guided CPV anatomy image, a highly similar figure could be achieved by mapping guided by the HDMM. (Clinical trial.gov number, ChiCTR-TNRC-11001390.).

Pulmonary vein isolation in 2012: is it necessary to perform a time consuming electrophysical mapping or should we focus on rapid and safe therapies? A retrospective analysis of different ablation tools

BACKGROUND

Pulmonary Vein Isolation (PVI) is evolving as an established treatment option in atrial fibrillation (AF). Different fluoroscopy-guided ablation devices exist either on the basis of expandable circumferential and mesh designs with mapping and ablation of pulmonary vein potentials, or of a balloon technology, a "single shot" device with a purely anatomical approach. Systematic comparisons between procedure duration (PD), fluoroscopy time (FT) and clinical outcome in using different ablation tools are lacking in the literature.

METHODS

In a single center retrospective analysis, 119 PVI procedures were performed between August 2008 and March 2011 in paroxysmal AF (PAF, 59.7%) and persistent AF (persAF, 40.3%) patients with mean age of 59.4±10.3 years and history of AF since 8.1±9.7 months. The PVI procedures were evaluated by comparing PD and FT using I) the High Density Mesh Mapper (HDMM), II) the High Density Mesh Ablator (HDMA), and III) the Arctic Front® Cryoballoon. The primary endpoints were FT and PD, the secondary endpoint was procedural safety and efficacy in short- and longterm follow-up.

RESULTS

The procedures performed for 119 patients (63.0 % male) included 42 PVIs with the HDMM (35.3 %), 47 with the HDMA (39.5 %) and 30 with the cryoballoon (25.2 %). Comparing the 30 first procedures in groups of 10 in the HDMM and HDMA group, PD and FT fell in the HDMM group (PD from 257.5 to 220.9 min and FT from 80.5 to 67.3 min, both p < 0.05) as well as in the HDMA group (PD from 182.9 to 147.2 min and FT from 41.02 to 29.1 min, both p < 0.05). In the cryoballoon group, there was a steep learning curve with a steady state after the first 10 procedures (PD and FT decreased significantly from 189.5 to 138.1 min and 36.9 to 27.3 min, p values 0.005 and 0.05 respectively). With respect to recurrence of AF in a 24 months follow up, the HDMM and cryoballoon group showed comparable results with ~72% of patients free of arrhythmias. None of the patients died due to severe complications, or suffered a hemodynamic relevant pericardial effusion and/or stroke. Impairment of the phrenic nerve was observed in three patients.

CONCLUSION

Use of the cryoballoon technology was associated with a steep learning curve and a reduced PD and FT; the long-term outcome was similar compared with the HDMM group. The efficacy and safety of the devices but also PD and FT should be respected as the strongest indicators of the quality of ablation. Further studies with long time follow-ups will show if the time for correct mapping of the PV potentials is a price we should be willing to pay or if we should adopt a "wait-and-see" attitude referring the AF recurrence.

Influence of the anatomic characteristics of the pulmonary vein ostium, the learning curve, and the use of a steerable sheath on success of pulmonary vein isolation with a novel multielectrode ablation catheter

AIMS

Anatomic variability of the pulmonary vein (PV) ostium may adversely affect isolation rates with the circular fixed-size pulmonary vein ablation catheter (PVAC). We wanted to assess the influence on PV isolation rates of anatomic characteristics of the ostium, increasing experience of four different operators, and additional use of a steerable sheath.

METHODS AND RESULTS

In the first 190 patients (pts) undergoing PVAC ablation, minimum/maximum diameter, area and shape of the PV ostia, and the length of a common ostium were analysed from computed tomography 3D reconstructions of the left atrium and related to isolation rates. In addition, a comparison was drawn between pts at the beginning and after completion (isolation of all PVs in ≥ 85% of pts) of the learning curve, and the effect of a steerable sheath was assessed. Pulmonary vein isolation was achieved with the PVAC alone in 85% of pts and in 94% of veins after a median procedure and ablation time of 154 [interquartile ranges (IQR): 120, 200] and 51 (IQR: 38, 70) min. An increase in isolation rates was observed after the first 60 pts (73 vs. 90% of pts; P< 0.01; 88 vs. 96% of PVs; P< 0.001), coincident with routine use of a steerable sheath. Anatomic characteristics (larger minimum diameter and area) identified unsuccessful isolation only of the left inferior PV at the beginning of the learning curve.

CONCLUSIONS

Pulmonary vein isolation rates using this catheter are high. Anatomic variability of PV ostia modestly affects PV isolation rates. Standard use of a steerable sheath plays a major role in increasing isolation rates and overcoming 'difficult' anatomies.