Autonomic trigger patterns and anti-arrhythmic treatment of paroxysmal atrial fibrillation: data from the Euro Heart Survey.

AIMS: To investigate the clinical characteristics, management, and outcome of patients with paroxysmal atrial fibrillation (AF) associated with autonomic triggers. METHODS AND RESULTS: One thousand five hundred and seventeen patients with paroxysmal AF participated in the Euro Heart Survey on AF. We categorized patients according to trigger pattern as reported by the physician: adrenergic (AF associated with exercise, emotion or during daytime only and absence of vagal triggers), vagal (postprandial or night time only, without presence of adrenergic triggers) and mixed (combination of vagal and adrenergic triggers). Vagal AF was found in 91 patients (6%), adrenergic in 229 patients (15%) and mixed in 175 (12%) patients. Underlying heart disease was equally prevalent in the three groups. Among patients with vagal AF, 73% were treated with non-recommended drugs according to the guidelines. In vagal AF, non-recommended treatment was associated with a shift to persistent or permanent AF in 19% of the patients, compared with none in the group receiving recommended treatment (P = 0.06). CONCLUSION: This study is the first to address the issue of autonomic trigger patterns and AF in a large population. Autonomic trigger patterns were seen frequently in paroxysmal AF patients. Autonomic influences should be taken into consideration since non-recommended treatment may result in aggravation of vagal AF.     

Complex electrograms within the coronary sinus: time- and frequency-domain characteristics, effects of antral pulmonary vein isolation, and relationship to clinical outcome in patients with paroxysmal and persistent atrial fibrillation

Background: The mechanistic and clinical significance of complex fractionated atrial electrograms (CFAE) in the coronary sinus (CS) has been unclear. Methods and Results: Antral pulmonary vein isolation (APVI) was performed in 77 patients with paroxysmal (32) or persistent AF (45). CS electrograms recorded for 60 seconds before and after APVI were analyzed in the time‐ and frequency‐domains. Dominant frequency (DF), complexity index (CI: change in polarity of depolarization), and fractionation index (FI: change in direction of depolarization slope) were determined. Before APVI, there was no difference in DF, CI, or FI between paroxysmal and persistent AF. APVI resulted in a significant decrease in DF, CI, and FI in all patients. Baseline CI (43 ± 13/s vs 54 ± 14/s, P = 0.03) and FI (64 ± 23/s vs 87 ± 30/s, P = 0.02) were lower in patients with paroxysmal AF who had AF terminated by ablation than who did not. At 10 ± 2 months, 69% of patients with paroxysmal AF and 49% of patients with persistent AF were free from AF after single ablation. Baseline CI was higher among patients with paroxysmal AF who had AF after APVI (56 ± 20/s vs 44 ± 10/s, P = 0.03). In patients with persistent AF, there was a larger decrease in DF after APVI among patients who remained free from AF (13 ± 11% vs 7 ± 9%, P < 0.05). Conclusions: Complexity of CS electrograms may reflect drivers of AF that perpetuate paroxysmal AF after APVI. In persistent AF, the extent to which APVI decreases DF in the CS correlates with efficacy, suggesting that DF identifies patients who may require additional ablation beyond APVI.     

Long-term outcome of catheter ablation in patients with atrial fibrillation originating from the superior vena cava

Long‐Term Outcome of SVC AF Ablation. Introduction: Data of the long‐term clinical outcome after superior vena cava (SVC) isolation are limited. We aimed to evaluate the long‐term outcome in patients with atrial fibrillation (AF) who had triggers originating from the SVC and received catheter ablation of AF. Methods and Results: The study consisted of 68 patients (age 56 ± 12 years old, 32 males) who underwent the ablation procedure for drug‐refractory, symptomatic paroxysmal AF originating from the SVC since 1999. Group 1 consisted of 37 patients with AF initiated from the SVC only, and group 2 consisted of 31 patients with both SVC and pulmonary vein (PV) triggers. During a follow‐up period of 88 ± 50 months, the AF recurrence rate was 35.3% after a single procedure. The freedom‐from‐AF rates were 85.3% at 1 year and 73.3% at 5 years. In the baseline study, group 2 had larger left atrium (38 ± 4 mm vs 36 ± 5 mm, P = 0.04), left ventricle (50 ± 5 mm vs 46 ± 5 mm, P = 0.003), and PV diameters. Kaplan–Meier survival analysis showed a higher AF recurrence rate in group 2 compared to that in group 1 (P = 0.012). The independent predictor of an AF recurrence was a larger SVC diameter (P = 0.02, HR 1.4, 95% CI 1.1–1.8). Conclusion: Among the patients with paroxysmal AF originating from the SVC, 73% remained free of AF for 5 years after a single catheter ablation procedure. Superior vena cava isolation without PV isolation is an acceptable therapeutic strategy in those patients with AF originating from the SVC only. The SVC diameter was an independent predictor of AF recurrence. (J Cardiovasc Electrophysiol, Vol. 23, pp. 955‐961, September 2012)     

Clinical Value of Noninducibility by High-Dose Isoproterenol Versus Rapid Atrial Pacing After Catheter Ablation of Paroxysmal Atrial Fibrillation

Noninducibility by High‐Dose Isoproterenol. Objective: To determine the relative clinical value of noninducibility of atrial fibrillation (AF) by isoproterenol (ISO) and by rapid atrial pacing (RAP) in patients with paroxysmal AF (PAF). Background: AF can be induced by RAP or ISO in >85% of patients with PAF. Methods: ISO was administered in escalating doses of 5, 10, 15, and 20 μg/min in 112 patients (age = 56 ± 13 years) with PAF before radiofrequency catheter ablation. AF was inducible in 97 of 112 patients (87%) at a mean dose of 15 ± 5 μg/min. RAP induced AF in the remaining 14 of 15 patients. Antral pulmonary vein (PV) isolation (APVI) was followed by ablation of complex fractionated atrial electrograms (CFAEs) as necessary to terminate AF and render AF noninducible in response to ISO. Results: AF terminated during APVI in 72 of 111 patients (65%) and after APVI plus ablation of CFAEs in 11 of 111 patients (10%). In the remaining 28 patients (25%), sinus rhythm was restored by transthoracic cardioversion. RAP was performed in the last 61 consecutive patients who were rendered noninducible by ISO. RAP initiated AF in 20 of 61 patients (33%) and atrial flutter in 6 patients (10%). No additional ablation was performed if AF was induced with RAP; however, atrial flutter was targeted. At 12 ± 5 months, 63/75 patients (84%) who were noninducible by ISO and 2 of 8 (25%) who still were reinducible by ISO were free from recurrent AF after a single ablation procedure without antiarrhythmic drugs (P = 0.001). AF recurred in 20 of 36 patients (56%) who required cardioversion for persistent AF after ablation (P < 0.001). Among the 61 patients who also underwent RAP, 12 of 20 (60%) who were, and 31 of 41 (76%) who were not inducible by RAP were free from recurrent AF (P = 0.21). The accuracy of noninducibility as a predictor of clinical outcome was 83% with ISO and 64% by RAP (P = 0.03). Conclusions: The response to isoproterenol after catheter ablation of PAF more accurately predicts clinical outcome than the response to RAP. (J Cardiovasc Electrophysiol, Vol. 21, pp. 13–20, January 2010)     

Catheter ablation of atrial fibrillation in octogenarians: safety and outcomes

AF Ablation in Octogenarians. Introduction: Radiofrequency catheter ablation (RFCA) is an effective treatment for atrial fibrillation (AF), although studies evaluating the role of RFCA have largely excluded elderly patients. We report the safety and outcomes of RFCA of AF in octogenarians. Methods and Results: From 2008 to 2011, out of 2,754 consecutive patients undergoing RFCA of AF, 103 (3.7%) had ≥80 years (age 85 ± 3 years, 4 with >90 years). Pulmonary vein (PV) antrum isolation was performed in paroxysmal AF. In nonparoxysmal AF, ablation was extended to the entire left atrial posterior wall and to complex fractionated electrograms. Non‐PV triggers were disclosed by isoproterenol challenge at the end of the procedure and targeted for ablation. Octogenarians presented a high rate of non‐PV triggers (84% vs 69%, P = 0.001), especially in patients with paroxysmal AF (62% vs 19%, P < 0.001); non‐PV triggers were most commonly mapped in the coronary sinus (54%), left atrial appendage (32%), interatrial septum and superior vena cava (14%). After a mean follow‐up of 18 ± 6 months, 71 (69%) octogenarians remained free from AF recurrence off antiarrhythmic drugs after a single procedure (vs 71% in patients <80 years, P = 0.65). The success rate reached 87% after 2 procedures. Total periprocedural complication rates also did not differ between the 2 age groups. Conclusions: RFCA of AF is safe and effective in octogenarians. A high rate of non‐PV triggers is present in these patients, and targeting multiple structures other than the pulmonary veins is often necessary to achieve long‐term success. (J Cardiovasc Electrophysiol, Vol. 23, pp. 687‐693, July 2012)     

Time- and frequency-domain characteristics of atrial electrograms during sinus rhythm and atrial fibrillation

Ablation and Spectral Characteristics of Fibrillation. Background: Complex fractionated atrial electrograms (CFAE) have been considered to be helpful during catheter ablation of atrial fibrillation (AF). The purpose of this study was to analyze the characteristics of CFAEs recorded during sinus rhythm (SR) and AF, and to determine their relationship to perpetuation of AF and clinical outcome. Methods and Results: Antral pulmonary vein isolation (APVI) was performed in 34 consecutive patients (age = 59 ± 10 years) with paroxysmal AF who presented in SR. Time‐ and frequency‐domain characteristics of electrograms recorded from the same sites in the coronary sinus (CS) were analyzed during SR and AF, before and during isoproterenol infusion. There was a modest correlation in fractionation index (FI: change in the direction of depolarization, r = 0.40, P = 0.001) and complexity index (CI: change in the polarity of depolarization, r = 0.41, P = 0.001), but not in the dominant frequency (DF) between SR and AF. There was no relationship between the DF and CI or FI during AF. Isoproterenol was associated with an increase in DF during AF (6.6 ± 0.9 vs 5.1 ± 0.6 Hz, P < 0.001) but had no effect on CI or FI (P = 0.6). A higher CI (58.3 ± 21.0/s vs 38.0 ± 21.0/s, P < 0.01), and FI (123.5 ± 44.8/s vs 75.6 ± 44.6/s, P < 0.01) during AF were associated with a lower likelihood of termination of AF during APVI and a higher probability of recurrent AF after ablation. Ratio of FI during AF to SR was also higher when AF persisted than terminated after APVI (29.7 ± 12.4 vs 19.1 ± 9.7, P = 0.002). However, time‐ or frequency‐domain parameters during SR were not predictive of termination or clinical outcome. Conclusions: Structural and functional properties of the atrial myocardium during AF contribute to electrogram complexity, which may indicate the presence of extra‐PV mechanisms of AF that are not eliminated by APVI. Mapping of complex electrograms in SR is not likely to be sufficient to identify drivers of AF. (J Cardiovasc Electrophysiol, Vol. 22, pp. 851‐857, August 2011)     

Pulmonary vein isolation for vagotonic, adrenergic, and random episodes of paroxysmal atrial fibrillation

INTRODUCTION: Based on the clinical history, paroxysmal atrial fibrillation (PAF) may be classified as vagotonic, adrenergic, or random. It is unclear whether pulmonary vein (PV) isolation is equally effective for these types of PAF. METHODS AND RESULTS: Segmental ostial ablation to isolate the PVs was performed in 188 consecutive patients (mean age 53 +/- 12 years) with PAF. Based on the clinical history, PAF was classified as random in 136 patients (72%), adrenergic in 30 (16%), and vagotonic in 22 (12%). Three or four PVs were targeted for isolation in all patients, and successful isolation was achieved in 96% of targeted PVs. At 1-year follow-up, 69% of patients with random AF, 83% of patients with adrenergic AF, and 50% of patients with vagotonic AF were free from recurrent episodes of AF in the absence of any antiarrhythmic drug therapy. Vagotonic AF was an independent clinical predictor of recurrent AF (P = 0.03). CONCLUSION: PV isolation has a lower efficacy in patients with vagotonic PAF than in patients with adrenergic or random episodes of PAF, suggesting that the PVs less often play an important role in vagotonic PAF.     

Identifying the relationship between the non-PV triggers and the critical CFAE sites post-PVAI to curtail the extent of atrial ablation in longstanding persistent AF

Relationship Between the Non‐PV Triggers and the Critical CFAE Sites. Background: Complex fractionated atrial electrograms (CFAE) ablation has been performed in addition to pulmonary veins (PV) isolation to increase the success rate of atrial fibrillation (AF) ablation in patients with longstanding (LS) persistent AF. The mechanism underlying the clinical benefit of CFAE ablation remains, however, poorly understood. Objective: We compared the impact of CFAE ablation on the prevalence of non‐PV atrial triggers inducing AF in 2 groups of patients with LS persistent AF. One group underwent PVAI alone, and the other group underwent PVAI plus CFAE ablation. In addition, we correlated the site of non‐PV triggers with the presence of CFAE. Methods: A total of 98 consecutive patients with symptomatic drug refractory LS persistent AF presenting for ablation had a preablation electroanatomic CFAE map. Patients randomized to either isolation of the PVs and posterior wall (PVAI) (group I, n = 48 pts) or PVAI and biatrial ablation of CFAEs (group II, 50 pts). After ablation, infusion of isoproterenol up to 30 mcg/min was given to reveal non PV foci inducing AF. Those foci were mapped and correlated with CFAE regions and ablated. Results: A total of 19 patients (76%) with PV foci inducing AF were associated with either stable or transient CFAE after PVAI, respectively, in 12 patients (48%) and 7 patients (28%). A total of 20 (42%) non‐PV triggers were observed in group I versus 5 (10%) in group II (P < 0.001) in 18 and 5 patients, respectively. After a mean f/u of 17.2 ± 5.2 months, 33 (69%) patients in group I and 36 (72%) patients in group II were in SR (P = NS). Conclusion: Non‐PV triggers inducing AF post‐PVAI were associated with the presence of stable or transient CFAE in 48% and 28% of cases, respectively, in LS persistent AF. CFAE ablation after PVAI was associated with a significantly higher elimination of those non‐PV triggers. This suggests that at least part of the beneficial effect achieved by CFAE ablation reflects elimination of non‐PV AF triggers. (J Cardiovasc Electrophysiol, Vol. pp. 1‐7)     

Triggering Pulmonary Veins: A Paradoxical Predictor for Atrial Fibrillation Recurrence After PV Isolation

Triggering Pulmonary Veins and Recurrence After Ablation . Purpose: To identify procedural parameters predicting recurrence of atrial fibrillation (AF) after a first circumferential pulmonary vein isolation (CPVI). Methods: One hundred seventy‐one patients undergoing CARTO‐guided CPVI for recurrent AF with a left atrial (LA) diameter <45 mm were studied. Follow‐up (symptoms and 7‐day Holter) was performed at 1 and 3 months and every 3 months thereafter. Clinical and procedural characteristics between successful patients and patients undergoing repeat ablation were compared. In addition, procedural parameters of the first procedure were compared with parameters during repeat ablation. Results: After first CPVI, 80% of patients were free of AF without antiarrhythmic drugs after a follow‐up (FU) of 28 ± 11 months (N = 136). Thirty‐five patients (20%) had recurrence of AF of which 25 underwent repeat ablation (N = 25). Clinical characteristics did not differ between the successful and repeat group. A triggering vein during the index procedure was significantly more observed in the repeat group (56% vs 11%, P < 0.001). At repeat ablation, 2.6 ± 1.2 veins per patient were reconnected. Whereas there was no preferential reconnecting PV, all PVs triggering at index were reconnected (100%). Conclusions: (1) In patients with symptomatic recurrent AF, the presence of a triggering pulmonary vein during ablation is a paradoxical predictor for AF recurrence after PV isolation. (2) The consistent finding of reconnection of the triggering PV at repeat ablation, suggests that, in these patients, the triggering PV is the culprit vein and that reconnection invariably results in clinical AF recurrence. (3) The present study advocates a strategy of even more stringent PV isolation in case of a triggering PV. (J Cardiovasc Electrophysiol, Vol. 21, pp. 381–388, April 2010)     

Long‐Term Outcome of Catheter Ablation in Patients with Atrial Fibrillation Originating from Nonpulmonary Vein Ectopy

Long‐Term Outcome of NPV AF Ablation . Introduction: Data regarding the long‐term outcome of catheter ablation in patients with nonpulmonary vein (NPV) ectopy initiating atrial fibrillation (AF) are limited. We aimed to evaluate the long‐term result of patients with AF who had NPV triggers and underwent catheter ablation. Methods and Results: The study included 660 consecutive patients (age 54 ± 11 years old, 477 males) who had undergone catheter ablation for AF. Group 1 consisted of 132 patients with AF initiating from the NPV, and group 2 consisted of 528 patients with AF initiating from pulmonary vein (PV) triggers only. Patients from Group 1 were younger than those from Group 2 (51 ± 12 years old vs 54 ± 11 years old, P = 0.001) and were more likely to be females (34.4% vs 25.8%, P = 0.049). The incidences of nonparoxysmal AF (36.4% vs 16.3%, P < 0.001) and right atrial (RA) enlargement (31.3% vs 19%, P = 0.004) were higher, and the biatrial substrates were worse in Group 1 than those in Group 2 (left atrial voltage 1.5 ± 0.7 mV vs 1.9 ± 0.7 mV, P < 0.001, RA voltage 1.6 ± 0.5 mV vs 1.8 ± 0.6 mV, P = 0.014). During a follow‐up period of 46 ± 23 months, there was a higher AF recurrence rate in Group 1 than in Group 2 (57.6% vs 38.8%, P < 0.001). The independent predictors of AF recurrence were NPV trigger (P < 0.001, HR 2, 95% CI 1.4–2.85), nonparoxysmal AF (P = 0.021, HR 1.55, 95% CI 1.07–2.24), larger left atrial diameter (P = 0.002, HR 1.04, 95% CI 1.02–1.07) and worse left atrial substrate (P = 0.028, HR 1.3, 95% CI 1.03–1.64). Conclusion: Compared to AF originating from the PV alone, AF originating from the NPV ectopy showed a worse outcome. (J Cardiovasc Electrophysiol, Vol. 24, pp. 250‐258, March 2013)     

Predictors of recurrence in patients undergoing cryoballoon ablation for treatment of atrial fibrillation: the independent role of sleep-disordered breathing

Predictors of AF Recurrence After Cryoballoon PVI. Introduction: In patients with atrial fibrillation (AF) undergoing pulmonary vein isolation, cryoballoon technique (cryoPVI) has been adopted in many centers. This study aimed to evaluate predictors of AF recurrence including impact of sleep‐disordered breathing (SDB). Methods and Results: In 82 patients consecutively assigned to cryoPVI cardiorespiratory screening for SDB, assessment of medical history, ECG, echocardiography, standard laboratory measurement, and blood gas analysis were performed prior to intervention. After a 3‐month blanking period, a 7‐day Holter ECG was performed at 3, 6 and then every 6 months to determine AF recurrence. Seventy‐five patients (69 paroxysmal AF, 6 persistent AF, 22 female, age 60 ± 9 years) completed at least 6‐month follow‐up. Median follow‐up of 12 months (interquartile range 6–18 months) confirmed maintenance of sinus rhythm in 69.4% of these patients. Stepwise forward regression model revealed moderate to severe SDB (cut‐off apnea‐hypopnea‐index (AHI) ≥ 15 per hour; Hazard Ratio (HR) 2.95, P = 0.04), early recurrence of AF (HR 8.74, P < 0.001), persistent AF (HR 7.16, P < 0.001), preprocedural class III‐antiarrhythmic drug treatment (HR 3.63, P = 0.02), but not SDB per se (AHI ≥ 5 per hour) as independent predictors for AF recurrence. Conclusion: Moderate to severe SDB is a treatable condition that independently predicts AF recurrence in patients undergoing cryoPVI. Screening for SDB and adequate treatment may improve long‐term success of cryoPVI. (J Cardiovasc Electrophysiol, Vol. 23, pp. 18‐25, January 2012)     

Reversal of left ventricular dysfunction following ablation of atrial fibrillation

Background: Evaluation of ventricular rate control in atrial fibrillation (AF) can be difficult, and the presence of an AF‐induced ventricular cardiomyopathy due to intermittent poor rate control or other causes may be underestimated. The outcome with AF ablation in patients with a decreased left ventricular ejection fraction (LVEF) may provide insight into this important clinical issue. Objective: To determine the effect of pulmonary vein isolation on LVEF in patients with AF and decreased LVEF (≤50%). Methods: Ablation consisted of proximal isolation of arrhythmogenic pulmonary veins (PVs) and elimination of non‐PV triggers. LVEF was determined within 24 hours after ablation and again at up to 6 months follow‐up. Transtelephonic monitoring was performed routinely for 2–3 weeks prior to ablation, at 6 weeks, and 6 months post and with symptoms following ablation. AF control was defined as freedom from AF or marked (>90%) reduction in AF burden on or off previously ineffective antiarrhythmic medication. Results: AF ablation was performed in 366 patients and 67 (18%) patients had decreased LV function with a mean LVEF of 42 ± 9%. An average of 3.4 ± 0.9 PVs were isolated. AF control in the depressed LVEF group compared favorably with the normal EF group (86% vs. 87% P = NS), although more redo procedures were required (1.6 ± 0.8 vs 1.3 ± 0.6 procedures; P ≤ 0.05). Only 15 of 67 patients (22%) with decreased LVEF had shown tachycardia (>100 bpm) on repeated preablation ECG recordings during AF. In the decreased LVEF group, the LVEF increased from 42 ± 9% to 56 ± 8% (P < 0.001) after ablation. Conclusions: Patients with AF and decreased LVEF undergoing AF ablation have similar success to patients with normal LVEF and have improvement in LVEF after ablation. These results suggest the presence of a reversible AF‐induced ventricular cardiomyopathy in many patients with AF and depressed LV function. The presence of under‐recognized and reversible cardiomyopathy even when tachycardia is not persistent is important to recognize.     

Low-level right vagal stimulation: anticholinergic and antiadrenergic effects

Right Vagal Stimulation Suppresses Atrial Fibrillation. Introduction: We sought to extend the use of low‐level vagal stimulation by applying it only to the right vagus nerve (LL‐RVS) to suppress atrial fibrillation (AF). Methods: In 10 pentobarbital anesthetized dogs, LL‐RVS (20 Hz, 0.1 ms pulse width) was delivered to the right vagal trunk via wire electrodes at voltages 50% below that which slowed the sinus rate (SR) or atrio‐ventricular conduction. Electrode catheters were sutured at multiple atrial and pulmonary vein (PV) sites to record electrograms. LL‐RVS continued for 3 hours. At the end of each hour, 40 ms of high‐frequency stimulation (HFS; 100 Hz, 0.01 ms pulse width) was delivered 2 ms after atrial pacing (during the refractory period) to determine the AF threshold (AF‐TH) at each site. Other electrodes were attached to the superior left ganglionated plexi (SLGP) and right stellate ganglion (RSG) so that HFS (20 Hz, 0.1 ms pulse width) to these sites induced SR slowing and acceleration, respectively. Microelectrodes inserted into the anterior right ganglionated plexi (ARGP) recorded neural activity. Results: (1) Three hours of LL‐RVS induced a progressive increase in AF‐TH at all sites (all P < 0.05). (2) The SR slowing and acceleration response induced by SLGP and RSG stimulation, respectively, was blunted by LL‐RVS. (3) The frequency and amplitude of the neural activity recorded from the ARGP were markedly inhibited by LL‐RVS. Conclusions: LL‐RVS suppressed AF inducibility and the chronotropic responses to parasympathetic and sympathetic stimulation. Inhibition of neural activity in the GP may be a mechanism underlying these results. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1147‐1153, October 2011)     

Pulmonary Vein Antral Isolation and Nonpulmonary Vein Trigger Ablation without Additional Substrate Modification for Treating Longstanding Persistent Atrial Fibrillation

PV Ablation for Persistent Atrial Fibrillation. Introduction: Effectiveness of antral pulmonary vein isolation (PVAI) and ablation of non‐PV triggers (non‐PVTA) in controlling longstanding persistent atrial fibrillation (AF) has not been reported. We sought to describe clinical outcomes with this ablation strategy in patients (pts) followed for at least 1 year. Methods: Two hundred pts underwent PVAI for longstanding persistent AF and were followed for recurrence. Thirty‐three pts with <1‐year follow‐up and 37 pts with additional RF atrial ablation were excluded, leaving 130 pts for analysis. Results: All 130 pts (108 men, mean LA 4.7 ± 0.6 cm, mean AF duration of 38 ± 44 months) underwent PVAI with entrance/exit block. In addition, 24 pts (15 pts during the initial procedure and 9 additional pts at repeat ablations) had 40 non‐PVTA, including 3 with AVNRT. During follow‐up, atrial flutter (AFL) was noted in 7 (5%) pts. The AF‐free survival after single procedure without antiarrhythmic drugs (AAD) was 38%. Repeat AF or AFL ablation was performed in 37 pts (28%) with PV reconnection uniformly identified (3.7 ± 0.5 veins/pt). During mean follow‐up of 41.1 ± 23.8 months (range 12–103 months), 85/130 pts (65%) were in sinus rhythm with 65 pts (50%) off AAD, 20 pts (15%) on AAD. Additionally, 9 pts (7%) have had rare episodes of AF such that 72% of pts have had good long‐term clinical outcome. Of the 36 pts with recurrent AF, 20 pts have not had a repeat procedure. Conclusions: PVAI with non‐PVTA for longstanding persistent AF provides good long‐term AF control in over 70% of patients with infrequent (5%) AFL. AAD therapy and repeat PVAI may be required for this optimal outcome. (J Cardiovasc Electrophysiol, Vol. 23, pp. 806‐813, August 2012)     

Shortening of fibrillatory cycle length in the pulmonary vein during vagal excitation.

OBJECTIVES: The goal of the present prospective study is to evaluate the impact of vagal excitation on ongoing atrial fibrillation (AF) during pulmonary vein (PV) isolation. BACKGROUND: The role of vagal tone in maintenance of AF is controversial in humans. METHODS: Twenty-five patients (18 with paroxysmal AF, 7 with chronic AF) were selected by occurrence of vagal excitation during AF (atrioventricular [AV] block: R-R interval >3 s) produced by PV isolation. Fibrillatory cycle length (CL) in the targeted PV and coronary sinus (CS) were determined before, during, and after vagal excitation. The CL was available at PV ostium during vagal excitation in 11 patients. RESULTS: Forty-eight episodes of vagal excitation were observed. During vagal excitation, CL abruptly decreased both in CS and PV (CS, 164 +/- 20 ms to 155 +/- 23 ms, p < 0.0001; PV, 160 +/- 22 ms to 143 +/- 28 ms, p < 0.0001), and both returned to the baseline value with resumption of AV conduction. The decrease in PVCL occurred earlier (2.5 +/- 1.5 s vs. 4.0 +/- 2.6 s, p < 0.01) and was of greater magnitude than that in CSCL (16 +/- 16 ms vs. 8 +/- 9 ms, p < 0.01). A sequential gradient of CL was observed from PV to PV ostium and CS during vagal excitation (138 +/- 29 ms, 149 +/- 24 ms, and 159 +/- 26 ms, respectively). The decrease in CL was significantly greater in paroxysmal than in chronic AF (CS, 11 +/- 9 ms vs. 5 +/- 7 ms, p < 0.05; PV, 23 +/- 25 ms vs. 8 +/- 14 ms, p < 0.05). CONCLUSIONS: Vagal excitation is associated with shortening of fibrillatory CL. This occurs earlier in PV with a sequential gradient to PV ostium and CS, suggesting that vagal excitation enhances a driving role of PV.     

Efficacy and safety of targeted focal ablation versus PV isolation assisted by magnetic electroanatomic mapping

INTRODUCTION: Pulmonary vein (PV) triggers initiate atrial fibrillation (AF). The aim of this study was to compare the outcome of focal PV ablation versus targeted PV electrical isolation aided by multipolar catheter recordings in the coronary sinus (CS) and right atrium and magnetic electroanatomic mapping (MEAM) for drug-refractory AF. METHODS AND RESULTS: Multipolar recordings identified PVs with triggers based on PV ostial pace map match for spontaneous and provoked triggers. PV triggers were provoked by isoproterenol, adenosine, and AF induction followed by cardioversion. MEAM defined PV ostial anatomy and assisted in localization of AF trigger and ablation lesions. All focal PV ablation procedures preceded PV isolation procedures at our institution. To limit a learning curve effect and validate the comparison, the results included outcome of procedures by a single experienced operator in the last 32 consecutive patients undergoing focal PV ablation and in 75 consecutive patients undergoing PV isolation. Patient characteristics were similar with respect to mean age (50 vs 52 years), mean left atrial size (4.3 vs 4.2 cm), presence of paroxysmal AF (84% vs 88%), and demonstration of non-PV triggers (16% in both groups). PV isolation was confirmed in 99% of PVs by multipolar circular catheter. MEAM confirmed noncircumferential ostial ablation in 69% of PVs. Patients undergoing PV isolation had less AF from PV triggers at the end of ablation (1% vs 16%, P < 0.01); had less AF at 2 months (17% vs 42%, P < 0.001); and had 1-year freedom from AF of 80% versus 45% (P < 0.001). Adverse events were low in both groups with no stroke or symptomatic PV stenosis. CONCLUSION: Using the described techniques, PV electrical isolation of PVs demonstrating spontaneous and/or provoked triggers is superior to focal PV ablation, with marked differences in outcome by 2 months. MEAM confirmed the noncircumferential nature of ostial ablation for effective isolation of most PVs and may play a role in the low risk and good outcome observed. The good outcome of targeted PV isolation as described suggests the need for a prospective comparison of targeted versus empiric PV isolation techniques.     

Catheter Ablation of Long‐Standing Persistent Atrial Fibrillation: A Lesson from Circumferential Pulmonary Vein Isolation

Catheter Ablation of Long‐Standing Persistent AF. Introduction: Circumferential pulmonary vein isolation (CPVI) is associated with a high success rate in patients with paroxysmal and persistent atrial fibrillation (AF). However, in patients with long‐standing persistent AF, the ideal ablation strategy still remains a matter of debate. Methods and Results: Two‐hundred and five patients underwent catheter ablation for long‐standing persistent AF defined as continuous AF of more than 1‐year duration. In a first step, all patients underwent CPVI. If direct‐current cardioversion failed following CPVI, ablation of complex fractionated atrial electrograms (CFAEs) was performed. The goal was conversion into sinus rhythm (SR) or, alternatively, atrial tachycardia (AT) with subsequent ablation. A total of 340 procedures were performed. CPVI alone was performed during 165 procedures in 124 of 205 (60.5%) patients. In the remaining 81 patients, additional CFAE ablation was performed in 45, left linear lesions for recurrent ATs in 44 and SVC isolation in 15 patients, respectively, resulting in inadvertent left atrial appendage isolation in 9 (4.4%) patients. After the initial ablation procedure, 67 of 199 patients remained in SR during a mean follow‐up of 19 ± 11 months. Six patients were lost to follow‐up. After a mean of 1.7 ± 0.8 procedures, 135 of 199 patients (67.8%) remained in SR. Eighty‐six patients (43.2%) remained in SR following CPVI performed as the sole ablative strategy. Conclusions: CPVI alone is sufficient to restore SR in 43.2% of patients with long‐standing persistent AF. Multiple procedures and additional ablation strategies with a significant risk of inadvertent left atrial appendage isolation are often required to maintain stable SR. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1085‐1093)     

Pulmonary Vein Antral Isolation for Paroxysmal Atrial Fibrillation: Results from Long‐Term Follow‐Up

Long‐Term Follow‐Up After Atrial Fibrillation Ablation . Introduction: Pulmonary veins play an important role in triggering atrial fibrillation (AF). Pulmonary vein isolation (PVI) is an effective treatment for patients with paroxysmal AF. However, the late AF recurrence rate in long‐term follow‐up of circumferential PV antral isolation (PVAI) is not well documented. We sought to determine the time to recurrence of arrhythmia after PVAI, and long‐term rates of sinus rhythm after circumferential PVAI. Methods: One hundred consecutive patients with a mean age of 54 ± 10 years, with paroxysmal AF who underwent PVAI procedure were analyzed. Isolation of pulmonary veins was based on an electrophysiological and anatomical approach, with a nonfluoroscopic navigation mapping system to guide antral PVI. Ablation endpoint was vein isolation confirmed with a circular mapping catheter at first and subsequent procedures. Clinical, ECG, and Holter follow‐up was undertaken every 3 months in the first year postablation, every 6 months thereafter, with additional prolonged monitoring if symptoms were reported. Time to arrhythmia recurrence, and representing arrhythmias, were documented. Results: Isolation of all 4 veins was successful in 97% patients with 3.9 ± 0.3 veins isolated/patient. Follow‐up after the last RF procedure was at a mean of 39 ± 10 months (range 21–66 months). After a single procedure, sinus rhythm was maintained at long‐term follow‐up in 49% patients without use of antiarrhythmic drugs (AADs). After repeat procedure, sinus rhythm was maintained in 57% patients without the use of AADs, and in 82% patients including patients with AADs. A total of 18 of 100 patients had 2 procedures and 4 of 100 patients had 3 procedures for recurrent AF/AT. Most (86%) AF/AT recurrences occurred ≤1 year after the first procedure. Mean time to recurrence was 6 ± 10 months. Kaplan–Meier analysis on antiarrhythmics showed AF free rate of 87% at 1 year and 80% at 4 years. There were no major complications. Conclusion: PVAI is an effective strategy for the prevention of AF in the majority of patients with PAF. Maintenance of SR requires repeat procedure or continuation of AADs in a significant proportion of patients. After maintenance of sinus rhythm 1‐year post‐PVAI, a minority of patients will subsequently develop late recurrence of AF. (J Cardiovasc Electrophysiol, Vol. 22, pp. 137‐141, February 2011)     

Role of Residual Potentials Inside Circumferential Pulmonary Veins Ablation Lines in the Recurrence of Paroxysmal Atrial Fibrillation

Residual Potentials After Pulmonary Vein Isolation. Background: Residual gaps due to incomplete ablation lines are known to be the most common cause of recurrent atrial fibrillation (AF) after catheter ablation. We hypothesized that any residual potentials at the junction of the left atrium and pulmonary vein (PV), inside the circumferential PV ablation (CPVA) lines, would contribute to the recurrence of AF or post‐AF ablation atrial flutter (AFL); therefore, the elimination of these potentials increases AF‐/AFL‐free survival rates. Methods and Results: One hundred and two patients with paroxysmal AF (PAF) were enrolled and prospectively randomized to a group with ablation of residual potentials as add‐on therapy to CPVA + PV electrical isolation (PVI) (group 1, n = 49), or a group without ablation of the residual potentials (group 2, n = 53). Post‐CPVA residual potentials, inside the ablation lines, were identified by contact bipolar electrode mapping catheter and a detailed 3‐dimensional voltage map. Twenty‐three patients in group 1 and 18 patients in group 2 had post‐CPVA residual potentials (46.9% vs 34.0%, P = 0.182). The AF‐/AFL‐free survival rate during follow‐up of 23.3 ± 7.9 months was not different in comparisons between the 2 groups (P = 0.818), and 79.6% and 81.1% of the patients in groups 1 and 2 maintained a sinus rhythm (P = 0.845), respectively. Conclusions: Residual potentials inside CPVA were commonly found in the patients with PAF after CPVA + PVI. Further ablation of residual potentials did not increase the efficacy of catheter ablation in patients with PAF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 959‐965, September 2010)     

Prospective assessment of short- and long-term quality of life after ablation for atrial fibrillation

Quality of Life After Ablation for Atrial Fibrillation. Background : This study prospectively assesses different aspects of short‐ and long‐term quality of life (QoL) after catheter ablation for atrial fibrillation (AF). An analysis of 7 validated generic and tailored questionnaires was performed with regard to the relation of QoL to ablation success. Methods : The study included 133 patients (74% men, age 57±10) who underwent pulmonary vein isolation ± linear or electrogram‐guided substrate modification for AF. QoL was quantitatively assessed at baseline, 3 months after ablation and at a median of 4.3 ± 0.5 years after ablation by the AF severity scale (AFSS), AF symptom checklist (AFSC), WHO‐5‐Well‐Being‐Index (WHO), Major Depression Inventory (MDI), Sleep and Vegetative disorder (SV), Vital Exhaustion (VE), and Illness intrusiveness (Ii). Results: QoL was improved significantly 3 months after ablation in all patients (regardless of ablation success or AF type) and stayed significantly improved after a median of 4.3±0.5 years (AFSS, AFSC, WHO, MDI, VE, PE (all P < 0.001), and SV (P = 0.007)). Patients who had a successful ablation improved significantly more than patients with an unsuccessful ablation in the AFSS, AFSC, and MDI questionnaire (delta change from baseline to long‐term follow‐up P = <0.001, P = <0.001, and P = 0.039, respectively). Conclusion: Overall, all patients significantly improved their QoL irrespective of the AF type in all questionnaires 3 months and 4 years after ablation. The increase in QoL was significantly greater in patients who underwent a successful ablation than patients with unsuccessful ablation in the AFSS, AFSC, and MDI questionnaire. Cardiovasc Electrophysiol, Vol. 23, pp. 121‐127, February 2012)