Segmental Pulmonary Vein Isolation Research Articles

Image integration increases efficacy of paroxysmal atrial fibrillation catheter ablation: results from the CartoMergeTM Italian Registry

The aim of this study was to investigate whether circumferential pulmonary vein (PV) isolation guided by image integration improves the procedural and clinical outcomes of atrial fibrillation (AF) ablation in comparison with segmental PV isolation and circumferential PV isolation guided by three-dimensional (3D) electroanatomical mapping alone. Procedural and clinical outcomes of 573 patients who underwent their first catheter ablation for paroxysmal AF between January 2005 and April 2007 were collected from 12 centres. We evaluated three techniques: segmental ostial PV isolation (SOCA group, 240 patients), circumferential PV isolation guided by electroanatomical mapping (CARTO group, 107 patients), and circumferential PV isolation guided by electroanatomical mapping integrated with magnetic resonance/computed tomographic images of the left atrium (MERGE group, 226 patients). Procedure duration proved to be shorter in MERGE group patients than in CARTO group patients (P < 0.04), but longer than in SOCA group patients (P < 0.0001). During follow-up, atrial tachyarrhythmias relapsed more frequently in SOCA group patients (44.6%) and CARTO group patients (41.7%) than in MERGE group patients (22.6%; P < 0.0001). In patients with paroxysmal AF, circumferential PV isolation guided by image integration significantly improves clinical outcome in comparison with both circumferential PV isolation guided by 3D mapping alone and with segmental electrophysiologically guided PV isolation.

Five-Year Outcomes After Segmental Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation

Most studies evaluating the efficacy of atrial fibrillation (AF) ablation report follow-up periods of 1 year to 2 years, but few report long-term results of > or =5 years after ablation. Therefore, we evaluated the long-term efficacy (i.e., >5 years) of segmental antrum pulmonary vein isolation (PVI) for paroxysmal AF. Seventy-one patients (60 +/- 10 years, 56 men) who underwent PVI for paroxysmal AF from January 1, 2002, to August 31, 2003, were followed for at least 5 years after their index ablation procedure. Five-year outcomes were determined at last clinic visit, by telephone encounters, and by cardiac monitoring when available. After 1 ablation, off antiarrhythmic drugs, 61 patients (86%) were free of symptomatic AF at 12 months, 56 patients (79%) at 24 months, and 40 patients (56%) at 63 +/- 5 months. Sixteen patients (22.5%) had AF recur after the second year after ablation. Thirty-one patients underwent > or =1 repeat ablations (1.6 +/- 0.9 per patient). After multiple procedures, 58 patients (81%) were free of symptomatic AF off antiarrhythmic drugs at 63 +/- 5 months after their initial ablation; however, in 18 of these patients who received multiple ablation procedures, mean duration of follow-up after the last ablation was only 13.5 +/- 2.1 months. In conclusion, overall 5-year outcome after PVI for paroxysmal AF is similar to that previously reported for shorter-term follow-up (< or =2 years). However, late recurrences >2 years after initial ablation were frequent, and repeat ablation was often required to maintain freedom from symptomatic AF.

First Experiences for Pulmonary Vein Isolation with the High‐Density Mesh Ablator (HDMA): A Novel Mesh Electrode Catheter for Both Mapping and Radiofrequency Delivery in a Single Unit

Interventional therapy of atrial fibrillation (AF) is often associated with long examination and fluoroscopy times. The use of mapping catheters in addition to the ablation catheter requires multiple transseptal sheaths for left atrial access. The purpose of this prospective study was to evaluate feasibility and safety of pulmonary vein (PV) isolation using the high-density mesh ablator (HDMA), a novel single, expandable electrode catheter for both mapping and radiofrequency (RF) delivery at the left atrium/PV junctions. Twenty-six patients with highly symptomatic paroxysmal AF (14, 53.8%) and persistent AF (12, 46.2%) were studied. Segmental PV isolation via the HDMA was performed using a customized pulsed RF energy delivery program (target temperature 55-60 degrees C, power 70-100 W, 600-900 seconds RF application time/PV). All 104 PVs in 26 patients could be ablated by the HDMA. Segmental PV isolation was achieved with a mean of 3.25 +/- 1.4 RF applications for a mean of 603 +/- 185 seconds. Entrance conduction block was obtained in 94.2% of all PV. The mean total procedure and fluoroscopy time was 159.0 +/- 32 minutes and 33.5 +/- 8.6 minutes, respectively. None of the patients experienced severe acute complications. After 3 months no PV stenosis was observed, and 85.6% and 41.6% of the patients with PAF and persistent AF, respectively, did not report symptomatic AF. In this first study of PV isolation using the HDMA, our findings suggest that this method is safe and yields good primary success rates. The HDMA simplifies AF ablation, favorably impacting procedure and fluoroscopy times.

Segmental pulmonary vein isolation in atrial fibrillation: new insights from the high density mesh mapper technique in an electrophysiologically guided approach

As opposed to fundamental investigations into the nature of atrial fibrillation (AF) current clinical studies of AF ablation techniques sometimes only contain sparse information about the underlying electrophysiological properties. The purpose of this prospective, pilot study was to evaluate acute therapeutic success and clinical outcome after 6 month of segmental ostial ablation (SOA) using the High Density Mesh Mapper catheter (HDMM, BARD Electrophysiology, Lowell, MA, USA) for an electrophysiological guided approach. The HDMM is a novel, single expandable basket electrode catheter for high resolution recordings at the left atrium/pulmonary vein (PV) junction. SOA was performed by irrigated radiofrequency (RF) application around the HDMM. Entry- and exit conduction block, as well as decreased local electrode amplitude, were endpoints for short-term successful ablation. Seventy-two patients with highly symptomatic paroxysmal AF (PAF; 47, 65.2%), persistent AF (12, 16.7%) and permanent AF (13, 18.1%) were studied. Entrance conduction block was obtained in 93%, exit conduction block in 81% of all PV. After 6 month no PV stenosis was observed, 62 patients (86.1%) improved clinically, whereas 52 patients (72.2%) were free from arrhythmias and sinus rhythm was present favoring patients with PAF. In this first prospective study of PV isolation using the HDMM, our findings suggest, that this method is safe and yields good primary success rates and favourable clinical outcome at 6 month. The new technology based on high resolution recordings, offers beside good anatomical orientation a direct electrophysiological control for monitoring of bidirectional conduction block.

What is the optimal approach for ablation of paroxysmal atrial fibrillation?

The optimal approach for catheter ablation of paroxysmal atrial fibrillation (PAF) is the subject of some controversy. Recent guidelines define PAF as recurrent AF that terminates spontaneously within seven days. For patients with PAF, the three most commonly employed approaches for ablation include, (1) segmental ostial or antral pulmonary vein isolation (PVI), (2) circumferential pulmonary vein ablation (CPVA) alone or in combination with additional left atrial linear ablation (LALA), and (3) complex fractionated atrial electrograms (CFAE) ablation alone or in combination with segmental PVI or CPVA (with or without additional LALA). Each of these approaches will be described in detail in this article. Overall evidence suggests that segmental antral PVI may be as effective as CPVA with or without LALA in prevention of AF recurrence, but that CPVA with or without LALA may be associated with a higher incidence of atypical atrial flutter recurrence.

Vagal Modification Can Also Help Prevent Late Recurrence of Atrial Fibrillation After Segmental Pulmonary Vein Isolation

The relationship between vagal modification and paroxysmal atrial fibrillation (PAF) recurrence after segmental pulmonary vein (PV) isolation (S-PVI) was investigated. S-PVI was performed in 77 PAF patients using a multielectrode basket or circular catheter to achieve electrical disconnection of all 4 PVs independent of eliminating vagal reflexes. Serial Holter-recordings were obtained at baseline, immediately and 1, 3, 6, and 12 months after S-PVI to analyze the heart rate variability. Fifty-one patients were free from symptomatic PAF (Group A) and 26 had late PAF recurrences (Group B) at 12-month follow-up. Immediately after S-PVI, the root mean square of the successive differences (rMSSD) and high-frequency (HF) power, which reflected parasympathetic nervous activity, were significantly lower in Group A than in Group B (rMSSD: 33.6+/-26.0 vs 60.6+/-23.2 ms, P<0.05; ln HF: 8.73+/-0.84 vs 9.31+/-0.95 ms2, P<0.05). There were no significant differences in the average heart rate or ratio of the low-frequency to HF powers between the 2 groups. By multivariate analysis, only the HF immediately after S-PVI was an independent predictor of PAF recurrence (hazard ratio 1.707, 95% confidence interval 1.057-2.756, P<0.05). Vagal modification after S-PVI could also help prevent late recurrence of PAF.

Prognostic impact of hs-CRP and IL-6 in patients undergoing radiofrequency catheter ablation for atrial fibrillation

Aim. The aim of this study was to assess the predictive value of inflammatory markers in patients with paroxysmal/ persistent atrial fibrillation (AF) treated with radiofrequency (RF) catheter ablation. Methods. Forty-six consecutive patients, mean age 55 years (range 31 – 81 yrs), with paroxysmal or persistent AF were treated with either segmental or circumferential pulmonary vein isolation ablation technique. All patients presented with sinus rhythm on inclusion. Holter monitoring lasting at least 14 days was performed before ablation and after 3 months. Recurrent symptomatic AF or atrial tachycardia >10 minutes was considered failure and patients were offered a second ablation session. Interleukin-6 and high-sensitivity C-reactive protein were measured prior to ablation and at follow-up visits. Results. After a maximum of two ablations, 19 patients (41%) had SR without recurrence of AF after 12 months. Patients in SR had significantly lower left atrium diameter (p = 0.007) and lower values of both IL-6 (p = 0.007) and hs-CRP (p = 0.018) at baseline before ablation. IL-6 concentration prior to ablation was an independent predictor of recurrent AF (p = 0.027). Conclusion. In patients with a history of paroxysmal or persistent AF treated with RF catheter ablation, elevated levels of IL-6 and hs-CRP before ablation are independent predictors of recurrence of AF.

Feasibility and Safety of Remote-Controlled Magnetic Navigation for Ablation of Atrial Fibrillation

Radiofrequency ablation for atrial fibrillation (AF) involves complex catheter manipulation resulting in prolonged procedure time and fluoroscopy exposure. Remote magnetic navigation (RMN) represents a novel approach toward improving the ability to perform complex ablation. Forty patients underwent ablation for AF, 20 using RMN (NIOBE II, Stereotaxis, Inc) with a 4-mm-tip magnetic catheter (Celsius, Biosense Webster) and 20 using a conventional 8-mm-tip bidirectional ablation catheter (Blazer, Boston Scientific). All patients underwent a combined wide area circumferential ablation and segmental pulmonary vein (PV) isolation using a circular mapping catheter and cavotricuspid isthmus ablation for right atrial flutter. The procedural end point was PV entrance block. There was no difference in atrial size, left ventricular systolic function, or type of AF between groups. PV entrance block was achieved in all patients. Mean procedure time was 279 +/- 60 minutes in the conventional group versus 209 +/- 56 minutes in the RMN group (p <0.001). Mean fluoroscopy time in the conventional group was 58.6 +/- 21 minutes versus 19.5 +/- 9.8 in the RMN group (p <0.001). At 1 year there were 15 patients in the conventional group and 16 in the RMN group free from clinical AF and off antiarrhythmic drugs (p = NS). There were 2 additional ablations performed for atypical atrial flutter in the conventional group and 3 in the RMN group (p = ns). Ablation catheter char formation was not observed. There were no procedural complications. In conclusion, radiofrequency ablation of AF performed with RMN is safe and feasible. Compared with conventional hand-navigated ablation, RMN ablation results in similar clinical outcomes with decreased fluoroscopy and procedure times.

Abstract 4109: First experiences for Pulmonary Vein Isolation with the High Density Mesh Ablator

Interventional therapy of atrial fibrillation (AF) still is a complex procedure often associated with long examination- and fluoroscopy times. The use of mapping catheters in addition to the ablation catheter requires multiple transseptal sheats for left atrial access. The purpose of this prospective study was to evaluate feasibility and safety of pulmonary vein (PV) isolation using the high density mesh ablator (HDMA), a novel single, expandable electrode catheter for both mapping and radiofrequency (RF) delivery at the left atrium/PV junctions. 26 patients (PTS) with highly symptomatic paroxysmal AF (14, 53.8%) and persistent AF (12, 46.2%) were studied. Segmental PV isolation via the HDMA was performed using a customized pulsed RF energy delivery program (target temperature 55– 60 degrees, power 70 –100 Watt, 600 –900 seconds RFapplication time/PV). All 104 PV in 26 PTS could successfully be ablated by the HDMA. Segmental PV isolation was achieved with a mean of 3.25±1.4 RF applications for a mean of 603±185 sec. Entrance conduction block was obtained in &gt;94% of all PV. Mean total procedure and fluoroscopy time was 159.0±32 min and 33.5±8.6 min respectively. None of the PTS experienced severe complications. In this first study of PV isolation using the HDMA, our findings suggest that this method is safe and yields good primary success rates. Anatomical orientation and signal quality were good, allowing for excellent electrophysiological control. The HDMA simplifies the complex procedure of AF ablation, favorably impacting procedure and fluoroscopy times. Further studies are required to assess the long-term outcome.

Abstract 2752: Pulmonary Vein Isolation With And Without Additional Ablation Of Complex Fractionated Electrograms In Paroxysmal Atrial Fibrillation: Long-term Results Of A Prospective Randomized Study

Introduction: Segmental pulmonary vein isolation (PVI) leads to elimination of paroxysmal atrial fibrillation (AF) in approximately 75% of patients. Ablation of complex fractionated atrial electrograms (CFAE) is an alternative ablation strategy. In this prospective randomized study the long-term effect of PVI alone is compared to the effect of combined PVI and CFAE ablation in paroxysmal AF. Methods: 98 patients with paroxysmal AF (57±10 years, 74 male) were randomly assigned to PVI (48 patients) or PVI+CFAE ablation (50 patients). Additional CFAE ablation was performed in the PVI+CFAE group if AF was still inducible after PVI. Follow-up results were assessed with repetitive 7 days Holter ECG and clinical evaluation including repeat ablations. Results: Additional CFAE ablation was performed in 30/50 (60%) patients of the PVI+CFAE group with still inducible AF after PVI. In each group, 2 patients were lost to long term follow-up. In the intention-to-treat analysis at 3 months and after 19±8 months, there was no significant difference between both groups (36/48 [75%] and 34/46 [74%] patients in the PVI and 37/50 [73%] and 40/48 [83%] of patients in the PVI+CFAE ablation group in sinus rhythm [p=0.32]). In subgroup analysis, patients actually treated with the combined PVI+CFAE ablation approach had a significantly better long-term success (25/28; 89%) than patients with still inducible AF who underwent PVI only (22/30;73%; p=0.02). In both groups repeat ablations were performed in 31% (PVI group; 15/48 patients) and 35% (PVI+CFAE group; 17/48 patients) (p=n.s). After 9 months, significantly more patients in the PVI+CFAE group experienced sustained regular atrial tachycardia than in the PVI group (6/44 versus 1/39 patients, P=0.02). Conclusion: The combination of PVI and CFAE ablation was equally effective than PVI alone in reaching freedom of AF in the intention-to-treat analysis. During long-term follow-up, patients actually treated with combined PVI+CFAE ablation had a significantly better outcome (89% vs. 73%). However, the rate of ablation-induced regular atrial tachycardias is inreased.

Abstract 2754: Pulmonary Vein Isolation Using Irrigated vs. Conventional 4-mm Tip Catheters- Do Short and Long-Term Outcomes Differ?

Open saline-irrigated tip ablation catheters have largely supplanted standard 4 mm tip ablation catheters for pulmonary vein isolation (PVI) of atrial fibrillation (AF), based on the assumption that the procedure is safer and more efficacious. However, outcomes after procedures that use identical techniques but different radiofrequency ablation catheters have not been compared. We studied 432 consecutive patients (age 57 ± 11 yrs) with AF (duration 7.9 ± 6.1 yrs) who underwent PVI; 320 (74 %) using a conventional 4 mm catheter and 112 (26 %) using an open irrigated tip catheter. Segmental PVI targeting the earliest LA-PV activation for all PVs in each patient was used for all patients regardless of catheter for the entire study cohort. Radiofrequency energy was delivered for ≥60 secs at each target site. The pts in the 2 groups were similar with respect to age, gender and duration of AF. All 432 pts had successful complete PVI. There was no significant difference in the total number of lesions delivered per PV in the conventional 4 mm group and the irrigated tip group (Table ) at the initial procedure. Following a single procedure, 227/ 320 (71%) patients in the conventional 4 mm and 75/112 (67%) in the irrigated group were AF-free on no antiarrhythmic drug at 12 mos (p=0.43). The number of patients who required repeat procedures was similar in the conventional group (57/320, 18%) and the irrigated tip group (22/112, 20%) (p=0.66). Serious complications were also similar (2.2% vs. 1.0 %, p=0.21) Contrary to conventional wisdom, the safety and 12 month efficacy of PVI for management of AF was similar for the two types of ablation catheters. These data suggest that PVI cohorts derived from differing ablation techniques can be combined for purposes of clinical investigation. Longer term outcomes may differ and should be studied as well.

The effect of different treatment strategies on left atrial size in patients with lone paroxysmal atrial fibrillation—a prospective cohort study

The effect of different treatment strategies of atrial fibrillation on left atrial (LA) size has not been compared in lone paroxysmal atrial fibrillation. The objective of the present study was to evaluate the evolution of LA size over time in patients who underwent different treatment interventions. Two hundred forty patients with lone paroxysmal atrial fibrillation were assigned to four groups. The circumferential pulmonary vein ablation (CPVA) group (n = 60) was treated with CPVA, segmental pulmonary vein isolation (SPVI) group (n = 60) with SPVI, AMIO group (n = 60) with amiodarone alone, and AMIO + LO group (n = 60) with amiodarone plus losartan. LA diameter was measured with transthoracic echocardiogram at baseline, 3, 6, 9, and 12 months after the interventions. In the CPVA group, LA size at third, sixth, ninth, and 12th month had a significant decrease than that at baseline and in the other three groups. LA size in patients with atrial fibrillation recurrence in the four groups was significant higher than that in patients with no atrial fibrillation recurrence (P = 0.002-0.001). The results suggested that a shortened LA size is not consistent with improved sinus rhythm maintenance. Although maintenance of sinus rhythm is not the only factor in determining shrinking or enlargement of the left atrium, inhibiting or eliminating activity of the pulmonary vein is very important for paroxysmal atrial fibrillation. Atrial fibrillation recurrence is a main factor contributing to enlargement of the LA.

The Dormant Epicardial Reconnection of Pulmonary Vein: An Unusual Cause of Recurrent Atrial Fibrillation After Pulmonary Vein Isolation

The case of a 65-year-old man with recurrent atrial fibrillation after undergoing segmental pulmonary vein isolation caused by the reconnection of previously isolated pulmonary veins is herein reported. Interestingly, frequent ectopic firings in the left superior pulmonary vein conducted to the left atrium, not through its ostium but through the supposed epicardial pathway at the region of the Marshall ligament, which had been absent during the first treatment session. The reisolation of the left superior pulmonary vein by radiofrequency application in the left atrial appendage thus successfully eliminated the occurrence of atrial fibrillation.

Pulmonary vein isolation using segmental versus electroanatomical circumferential ablation for paroxysmal atrial fibrillation

We tested the hypothesis that electroanatomic pulmonary vein (PV) antra encircling for the PV isolation will improve the outcome in treatment of paroxysmal atrial fibrillation (PAF), compared with segmental PV isolation. Fifty-four patients underwent segmental PV isolation (group 1) and 56 patients circumferential PV isolation (group 2) for symptomatic PAF in a randomized study. Following single ablation procedure, at the 48 +/- 8 month follow-up, 30 (56%) and 32 (57%) patients in groups 1 and 2 remained free of arrhythmia (P = 0.41). After repeat ablation, 43 (80%) and 45 (80%) patients in groups 1 and 2 were free of arrhythmia without antiarrhythmic drugs (AADs); 48 (89%) and 51 (91%) patients in groups 1 and 2 did not have arrhythmia recurrences without or with AADs. This study demonstrates no advantage in long-term arrhythmia-free clinical outcome after circumferential PV isolation in patients with frequent PAF.

Full‐Motion Two‐ and Three‐Dimensional Pulmonary Vein Imaging by Intracardiac Echocardiography After Pulmonary Vein Isolation

The pulmonary veins (PVs) are topographically complex and motile, so angiographic visualization of the PVs anatomy is limited. An imaging technique that accurately portrays the pulmonary vein (PV) anatomy would be valuable during and after catheter ablation procedures. We investigated whether three-dimensional (3D) intracardiac echocardiography (ICE) can visualize radiofrequency (RF)-induced tissue changes after PV isolation. We performed 3D ICE studies with a 9F, 9-MHz ICE catheter after segmental or extended PV isolation. The ICE catheter was placed 3-4 cm inside the PV ostium and mounted onto a pullback device. Sequential two-dimensional (2D) images of the full length of the vein were obtained in 0.3 mm steps with cardiac and respiratory cycle gating. Each image was fed into a computer, and the aggregate data set was reconstructed into a 3D, full-motion image. RF lesion location and lesion size were studied on 67 pullback images from 29 patients. The 2D and 3D reconstruction was possible for 27 left superior PVs, 13 left inferior PVs, 26 right superior PVs, and one right inferior PV. The ablation site was identified 3-7 mm inside the PV ostium, and a 1/2 - 4/5 circumferential area was ablated with no clinically relevant stenosis. No significant differences were found on the ablated area or ablation site between segmental and extensive PV isolation. The 2D and 3D ICE of the PVs provides detailed anatomical information of the proximal PVs, and RF-induced tissue changes in the PV wall can be visualized by ICE.

Long-Term Follow-Up After Cryothermic Ostial Pulmonary Vein Isolation in Paroxysmal Atrial Fibrillation

This study was designed to evaluate the long-term effect of segmental pulmonary vein (PV) cryoablation in patients with recent-onset paroxysmal atrial fibrillation (PAF). Patients with PAF have more triggers to initiate and less substrate to sustain atrial fibrillation (AF). Elimination of the potential initiators alone may be sufficient to abolish the arrhythmia. Patients with PAF were prospectively recruited from July 2001 to July 2005. If the triggers for AF were identified, PV cryoisolation of the arrhythmogenic vein(s) was performed. Otherwise, all PVs were isolated. Seventy patients with minimal or no heart disease (54 men; age 40 +/- 10 years) were enrolled. The duration of AF was 4 +/- 1 year. The left ventricular ejection fraction and left atrial size were 59 +/- 8% and 41 +/- 5 mm, respectively. An arrhythmogenic PV was found in 10 patients (14%). Complications occurred in 3 patients (4%). No PV stenosis or esophageal injury was detected during a mean follow-up of 33 +/- 15 months. Thirty-four patients (49%) achieved complete success (no AF and no antiarrhythmic drugs [AAD]); 15 patients (22%) had no recurrences with AAD; and 8 patients (11%), still with sporadic bursts of AF, improved >50% with AAD. Overall, 82% of the patients benefited from the procedure. Patients in whom the arrhythmogenic PV was identified and isolated had no recurrences. Pulmonary vein cryoisolation is effective in 82% of patients with recent-onset PAF during a mean follow-up of 33 +/- 15 (range 15 to 60) months. If the arrhythmogenic PV is identified and isolated, the long-term outcome is excellent, indicating no need to isolate all PVs.

Frequency of Recurrence of Atrial Fibrillation Within 48 Hours After Ablation and Its Impact on Long-Term Outcome

Because of delayed structural and electrophysiologic effects of radiofrequency ablation of atrial fibrillation (AF), early recurrence of AF after ablation does not necessarily indicate long-term ablation failure. This study was intended to assess the prognostic value of early recurrence of AF within 48 hours after ablation. The study included 234 patients (aged 23 to 80 years; 72% men) with symptomatic drug-resistant paroxysmal (n = 165) or persistent AF (n = 69) who underwent either Lasso-guided segmental pulmonary vein isolation (n = 83) or CARTO-guided left atrial circumferential ablation (n = 151). After a median follow-up of 12.7 months, 64% of patients with paroxysmal and 45% of patients with persistent AF were AF free. Early recurrence of AF occurred in 43% of patients and was more frequently observed in the persistent-AF group (paroxysmal vs persistent 39% vs 54%; p = 0.037). Early recurrence of AF was a significant predictor of long-term ablation failure in univariate (hazard ratio [HR] 2.29, p <0.001) and multivariate (HR 2.17. p <0.001) Cox regression analysis. Nevertheless, 46% of patients with early recurrence of AF were AF free during long-term follow-up compared with 68% of patients without early recurrence of AF. The prognostic value of early recurrence of AF was found in patients with paroxysmal (HR 2.05, p = 0.005) and persistent AF (HR 2.35, p = 0.013). In conclusion, early recurrence of AF within 48 hours after ablation was a significant predictor of a poor long-term ablation outcome. However, because nearly half the patients with early recurrence of AF remained AF free during long-term follow-up, early recurrence of AF should not automatically result in an early repeated procedure.

New high-density mapping catheter: helpful tool to assess complete pulmonary veins isolation

A 57-year-old female was referred to our hospital for radiofrequency (RF) ablation of paroxysmal drug refractory atrial fibrillation. Before ablation, a three-dimensional CT reconstruction of left atrium (LA) was provided with an integrated electroanatomic mapping system (Ensite NavX, St Jude Medical, St Paul, MN, USA). Initially, a segmental pulmonary veins (PVs) isolation guided by a decapolar variable circular mapping catheter (Lasso™, Biosense-Webster, Diamond Bar, CA, USA) was performed (Panel A). Radiofrequency applications, using an irrigated-tip catheter, …

Noninvasive Assessment of Atrial Substrate Change after Wide Area Circumferential Ablation: A Comparison with Segmental Pulmonary Vein Isolation

The wide area circumferential ablation (WACA) approach to atrial fibrillation is thought to result in 'substrate modification' perhaps related to autonomic denervation. We examined this prospectively by comparing WACA and segmental pulmonary vein isolation (PVI) using noninvasive surrogate markers. Heart rate variability (HRV) and signal averaged P wave (SAPW) data were derived from high-resolution (HR) recordings ('SpiderView' ELA Medical) made in sinus rhythm immediately before and 24 hours after ablation. Forty patients recruited (20 WACA; 20 PVI); cohorts were comparable. WACA caused marked SAPW change: P wave duration (PWD) (149[4.6] ms to 160[5.9] ms; P = 0.003), root mean square (RMS) (4.4[0.4]microV to 2.8[0.4]; P = 0.001) and energy content (30-150 Hz; 20.4 [3.6]microV(2)/s to 13.7[2.4]; P = 0.001). No significant change was seen after PVI. Heart rate increased after WACA and PVI (61.4 to 73.5 [P = 0.001]; 69.5 to 75.0 [P = 0.07], respectively). HRV was significantly influenced after WACA: low frequency power (LF) 5.7(0.4) to 3.6(0.4); P = 0.001), high-frequency power (HF) 4.6(0.4)-3.4(0.3); P = 0.024, and after PVI: LF 5.4(0.3) to 4.3(0.3); P = 0.024. HF: 4.4(0.4) to 3.0(0.4); P = 0.018). HR recordings exhibit change in HRV after WACA and PVI. Marked change in both HRV and SAPW is observed after WACA. SAPW variables provide a measure of atrial substrate change after WACA unrelated to autonomic denervation.

Prevalence and Severity of Left Atrial Edema Detected by Electron Beam Tomography Early After Pulmonary Vein Ablation

The aim of this study was to investigate the prevalence and severity of left atrial (LA) edema after pulmonary vein (PV) ablation and its effect on the cardiac function. Though extensive LA catheter ablation has been demonstrated to be more effective in curing paroxysmal atrial fibrillation (PAF) than segmental ostial pulmonary vein isolation (S-PVI), it might cause life-threatening complications, including congestive heart failure associated with LA edema. Fifty patients underwent S-PVI (Group S) and 27 underwent circumferential PV antrum ablation (Group C) for drug-refractory PAF. Enhanced electron beam tomography (EBT) was performed before, 1 or 2 days after, and 1 month after the PV ablation, and transthoracic ultrasound cardiography (UCG) was performed 1 month after the PV ablation in all patients. The EBT assessment revealed LA edema immediately after the PV ablation in 47 Group S patients and all Group C patients. The severity of the LA edema, number of radiofrequency applications, and amount of radiofrequency energy delivered during the PV ablation was significantly greater in Group C than in Group S. One month after the PV ablation, in all patients, the EBT assessment revealed that those edematous changes had disappeared, and the UCG assessment showed no reduction in the cardiac function. Left atrial edema was observed in a large portion of the patients immediately after the PV ablation, and the severity of the LA edema depended on the extent and amount of the radiofrequency energy delivered in the PV ablation. The LA edema soon disappeared naturally and did not reduce the cardiac function.