Efficacy of Additional Ablation of Complex Fractionated Atrial Electrograms for Catheter Ablation of Nonparoxysmal Atrial Fibrillation

Background: The efficacy of ablation of complex fractionated atrial electrograms (CFEs) in the single ablation procedure for nonparoxysmal atrial fibrillation (AF) patients is not well demonstrated. The aim of this study was to compare the ablation strategies of pulmonary vein isolation (PVI) plus linear ablation with and without additional ablation of CFEs in these patients.
Methods: Consecutive 60 patients (49 ± 11 years old, 50 male, 10 female) with nonparoxysmal AF underwent catheter ablation guided by a NavX mapping system. A stepwise approach included a circumferential PVI and left atrial (LA) linear ablation followed by either the additional ablation of continuous CFEs in the LA/coronary sinus (the first 30 patients) or not (the second 30 patients), detected by an automatic algorithm.
Results: There was no difference in the baseline characteristics between the two groups. Complete PVI eliminated some continuous CFEs and altered the distribution of CFEs. Following PVI and linear ablation, the remaining continuous CFEs were identified in 7.9 ± 10% mapping sites of the LA and CS, and were ablated successfully with a procedural AF termination rate of 53%. With a follow-up of 19 ± 11 months, a Kaplan–Meier analysis showed that the patients with additional ablation of the CFEs had a higher rate of sinus rhythm maintenance. Multivariate analysis showed the single procedure success could be predicted by the procedural AF termination and the additional ablation of continuous CFEs in the LA/CS.
Conclusions: Ablation of continuous CFEs after PVI and LA linear ablation had a better long-term efficacy based on the results of single-ablation procedure.     

Long-term safety and efficacy of circumferential ablation with pulmonary vein isolation

Background: Each of the two main approaches to catheter ablation of atrial fibrillation (AF, segmental and circumferential) is associated with moderate long-term efficacy.
Objective: To report the long-term outcomes of a modified technique that combines circumferential ablation with pulmonary vein (PV) isolation, determined by a circular mapping catheter and to determine the relationship between complete PV isolation and long-term efficacy.
Methods: The patient population was composed of 64 consecutive patients (47 men [73%]; age 59 ± 11 years) with AF who underwent catheter ablation. AF was paroxysmal in 29 (45%) and nonparoxysmal in 35 (55%). Each patient was followed for a minimum of 12 months.
Results: After a mean follow-up of 13 ± 1 months, the long-term single-procedure success rate was 45% (n = 29) with an additional 4% (n = 3) of patients demonstrating improvement. With repeat procedures in 19 patients, the overall long-term success rate was 62% (n = 40) with 9% (n = 6) demonstrating improvement. All the patients who underwent repeat ablations had recovered PV conduction. Incomplete PV isolation was the only independent predictor of failure. A major complication occurred in four (6%) patients, including three patients with vascular complications and one with cardiac tamponade.
Conclusion: Our results suggest that the long-term single-procedure efficacy of circumferential ablation with PV isolation in a cohort of patients with predominantly nonparoxysmal AF approaches 50%. Repeat procedures involving re-isolation of the PVs result in a significant improvement in outcomes. Complete electrical isolation of the PVs has a significant impact on the long-term efficacy of the procedure.     

Approaches to Catheter Ablation of Nonparoxysmal Atrial Fibrillation

Purpose of review

We describe the technical aspects and outcomes of several different ablation strategies for nonparoxysmal (persistent and long-standing persistent) atrial fibrillation (AF) and discuss our ablation strategy for these patients.

Recent findings

Catheter ablation is an effective treatment strategy for patients with AF. Outcomes of ablation in patients with nonparoxysmal forms of AF tend to be worse than in patients with paroxysmal AF. Several recent studies have examined the long-term ablation success rates of different ablation approaches in patients with nonparoxysmal AF. While observational studies have suggested benefit of several different ablation strategies for persistent AF, large randomized controlled studies have shown similar success rates with pulmonary vein isolation (PVI) alone as compared versus PVI plus additional ablation.

Summary

The optimal ablation strategy to achieve long-term freedom from recurrent arrhythmias in patients with nonparoxysmal AF remains controversial. Achieving durable PVI should be the cornerstone of AF ablation. Additional large-scale randomized controlled studies are necessary to determine whether additional ablation might result in improved long-term ablation success rates in these patients.

     

Catheter ablation is preferred over surgery for persistent atrial fibrillation

There are important limitations that can hinder outcomes of surgical ablation in nonparoxysmal patients with atrial fibrillation (AF), which is the typical AF population undergoing concomitant cardiac surgery for valve or ischemic heart disease. Incomplete lesions with recovered conduction or gaps as well as arrhythmias originating from areas not targeted by surgical ablation are commonly seen at the time of recurrence. Therefore, while it might be reasonable to perform AF surgery in this cohort, it is important to know these limitations and establish adequate postoperative rhythm monitoring to detect recurrences, which can be effectively addressed by catheter ablation.     

Impact of biomarkers of inflammation and extracellular matrix turnover on the outcome of atrial fibrillation ablation: importance of matrix metalloproteinase-2 as a predictor of atrial fibrillation recurrence

MMP‐2 Predicts the Outcome of AF Ablation. Introduction: Although catheter ablation can effectively eliminate atrial fibrillation (AF), the progression of atrial remodeling increases the risk of recurrence. AF is associated with inflammation and subsequent myocardial fibrosis. We therefore examined the possibility of determining the postablation prognosis of patients with AF using biomarkers of inflammation and collagen turnover. Methods and Results: Subjects were 50 patients who underwent catheter ablation for drug‐resistant AF. High‐sensitivity CRP (hs‐CRP), interleukin (IL)‐6, carboxyl‐terminal telopeptide of collagen type I (ICTP), metalloproteinase (MMP)‐2, tissue inhibitor of MMP‐2 (TIMP‐2), atrial natriuretic peptide (ANP), and brain natriuretic peptide (BNP) were measured before and 2.2 ± 0.8 months after ablation. During the follow‐up period of 14.0 (4.7–20.9) months, AF recurred in 21 of the 50 patients. Recurrence was associated with an MMP‐2 elevation (860.3 ± 120.8 ng/mL vs 687.0 ± 122.5 ng/mL [in patients without recurrence]), ICTP elevation (3.2 ± 1.1 ng/mL vs 2.7 ± 0.6 ng/mL), BNP elevation, greater body mass index, nonparoxysmal AF, and hypertension (P < 0.05 for all). Serum MMP‐2 and nonparoxysmal AF were shown by multivariate analysis to be independent predictors for postablation AF recurrence. Overall, hs‐CRP, IL‐6, ANP, and BNP levels decreased, and MMP‐2, TIMP‐2, and ICTP levels increased 2 months after ablation. Conclusions: Our finding that markers of collagen turnover were elevated in patients who experienced AF recurrence after ablation indicate that these markers might be a useful guide to identify a subgroup of AF patients who require extensive ablation strategies. A 2‐month postablation elevation in collagen turnover markers suggests that the wound healing process persists for that long after ablation. (J Cardiovasc Electrophysiol, Vol. 22, pp. 987‐993, September 2011)     

Left Atrial Appendage Wall‐Motion Velocity Associates with Recurrence of Nonparoxysmal Atrial Fibrillation after Catheter Ablation

Catheter ablation (CA) for nonparoxysmal atrial fibrillation (AF) is controversial due to its high recurrence rate. The aim of this study was to assess retrospectively the diagnostic value of preprocedural left atrial appendage (LAA) wall‐motion velocity in predicting recurrence of AF within 1 year after CA. We hypothesized that tissue Doppler‐derived measurement of LAA wall‐motion velocity associate with recurrence of AF within 1 year after CA. We retrospectively reviewed 47 consecutive patients with nonparoxysmal AF (defined as AF lasting for 1 week or longer) who underwent both transthoracic and transesophageal echocardiography before their first treatment by CA in a single center. Forty‐one patients aged 58 ± 10 years were included, and variables predicting the recurrence of AF within 1 year after CA were evaluated. Seventeen patients (41%) developed recurrence of AF within 1 year after CA. Univariate analyses showed that preprocedural LAA upward wall‐motion velocity at the apex assessed by transesophageal echocardiography was significantly lower in patients with recurrence of AF than those without recurrence (OR = 1.45, 95% CI: 1.13–2.01, P = 0.009). Multivariate logistic analyses including other potential predictors (duration of AF, left ventricular ejection fraction, E‐wave deceleration time, and left atrial wall‐motion velocity) identified LAA upward wall‐motion velocity at the apex as an independent predictor of outcome. These data suggest in patients with nonparoxysmal AF, preprocedural LAA upward wall‐motion velocity at the apex, as determined by tissue Doppler imaging during transesophageal echocardiography, may be a useful indicator for predicting recurrence of AF within 1 year after CA.     

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)     

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)     

Efficacy of cardiac autonomic denervation for atrial fibrillation: a meta-analysis

Cardiac Autonomic Denervation and AF. Introduction : Adjunctive complex fractionated atrial electrograms (CFAE) ablation or ganglionated plexi (GP) ablation have been proposed as new strategies to increase the elimination of AF, but the difference between CFAE/GP ablation and pulmonary vein isolation (PVI), as well as the combined effect of CFAE/GP plus PVI ablation were unclear. This meta‐analysis was designed to determine whether adjunctive cardiac autonomic denervation (CAD) was effective for the elimination of AF, and whether CAD alone was superior to PVI in AF patients. Methods: A systemic literature search in MEDLINE, EMBASE, and Cochrane Controlled Trials Register (CCRT) was performed and controlled trials comparing the effect of PVI plus CFAE/GP ablation with PVI, as well as CFAE/GP ablation with PVI were collected. Results : A total of 15 trials including 1,147 patients with AF were qualified for this meta‐analysis. CAD plus PVI significantly increased the freedom from AF/ATs (OR 1.85, 95% CI: 1.33–2.59, P = 0.29). Subgroup analysis showed that additional CAD increased the ratio of sinus rhythm maintenance in both paroxysmal AF (OR 1.69; 95% CI: 1.09–2.62, P = 0.41) and nonparoxysmal AF (OR 2.11, 95% CI: 1.14–3.90, P = 0.14). Besides, when compared respectively, adjunctive CAD was not superior to PVI (OR 0.31; 95% CI: 0.11–0.86, P = 0.002). Conclusion : This study suggested that CAD plus PVI significantly increase the freedom from recurrence of AF both in paroxysmal and nonparoxysmal patients. However, when compared alone, the benefit of CAD was not superior to PVI. (J Cardiovasc Electrophysiol, Vol. 23, pp. 592–600, June 2012)     

Correlative Anatomy for the Electrophysiologist: Ablation for Atrial Fibrillation. Part I: Pulmonary Vein Ostia,Superior Vena Cava,Vein of Marshall

Anatomy for Atrial Fibrillation. Ablation procedures for atrial fibrillation (AF) have become an established and increasingly used option for managing patients with symptomatic arrhythmia. The anatomic structures relevant to the pathogenesis of AF and ablation procedures are varied and include the pulmonary veins (PVs), other thoracic veins, the left atrial myocardium, and autonomic ganglia. Exact regional anatomic knowledge of these structures is essential to allow correlation with fluoroscopy and electrograms, and, importantly, to avoid complications from damage of adjacent structures within the chest. We have presented this information in a 2‐part series. In the present article, we examine the general anatomic characteristics of the PVs, superior vena cava, and vein of Marshall. Features of particular relevance for the invasive electrophysiologist are pointed out. In a subsequent article, we discuss the regional anatomy of the left and right atria and anatomic considerations in preventing complications during AF ablation. (J Cardiovasc Electrophysiol, Vol. 21, pp. 721‐730, June 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)     

The challenging face of focal atrial tachycardia in the post AF ablation era

Radiofrequency ablation (RFA) for atrial fibrillation (AF) has become one of the most common catheter ablation procedures performed worldwide. As experience and success in treating patients with paroxysmal AF have increased, more centers are performing ablation for persistent AF. Optimal results may require ablation beyond the pulmonary veins with extensive biatrial substrate modification required in some cases to restore sinus rhythm. On the road to sinus rhythm atrial tachycardias are generally encountered either acutely within the index procedure or following. This has led to an increase in the frequency of focal atrial tachycardia and a need to review our understanding and approach to this and how it differs following substrate modification in contrast with the de novo setting. This review aims to describe the differences in responsible mechanism and its translation to mapping and ablation of focal AT particularly in the post ablation atria (paAT).     

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.     

Characteristics and significance of very early recurrence of atrial fibrillation after catheter ablation

Very Early Recurrence of AF. Introduction: Early restoration of sinus rhythm following ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and improves the long‐term outcome. The purpose of this study was to determine the predictors and outcome in patients with very early AF recurrences (< 2 days). Methods and Results: Ablation was performed in 339 consecutive AF patients (paroxysmal AF = 262). Biatrial voltage was mapped during sinus rhythm. If recurrent AF occurred within 2 days following the ablation, electrical cardioversion was performed to restore sinus rhythm. Very early recurrences of AF occurred in 39 (15%) patients with paroxysmal AF and 26 (34%) with nonparoxysmal AF. Patients with very early recurrence had a higher incidence of nonparoxysmal AF (40% vs 18.6%, P< 0.001), requirement of electrical cardioversion during procedure, larger left atrial (LA) diameter (43 ± 7 vs 39 ± 6 mm, P< 0.001), lower left ventricular ejection fraction (54 ± 10% vs 59 ± 7, P< 0.001), longer procedural time, and lower LA voltage (1.5 ± 0.7 vs 1.9 ± 0.8 mV, P< 0.001). A multivariate analysis revealed that the independent predictors of a very early recurrence were a longer procedural time and lower LA voltage. During a follow‐up of 13 ± 5 months, a very early recurrence did not predict the long‐term outcome of a single procedure recurrence in the patients with paroxysmal AF, but was associated with a late recurrence in the nonparoxysmal AF patients. Conclusion: Very early recurrence occurred in patients with paroxysmal AF is not associated with long‐term recurrence. Nonparoxysmal AF is an independent predictor of late recurrence of AF in patients with very early recurrence. (J Cardiovasc Electrophysiol, Vol. pp. 1‐6)     

Non‐pulmonary vein triggers in nonparoxysmal atrial fibrillation: Implications of pathophysiology for catheter ablation

Rhythm control of persistent atrial fibrillation (AF) patients represents a challenge for the modern interventional cardiac electrophysiologist; as a matter of fact, there is still divergence regarding the best ablative approach to adopt in this population. Different investigational endpoints, variability of techniques and tools, significant technological evolution, and the lack of universally accepted pathophysiological models engendered a considerable heterogeneity in terms of techniques and outcomes, so much that the treatment of persistent subtypes of AF commonly still relies mainly on pulmonary vein (PV) isolation. The purpose of the present review is to report the current experimental and clinical evidence supporting the importance of mapping and ablating non‐PV triggers and describe our institutional approach for the ablation of nonparoxysmal AF.     

Concomitant atrial fibrillation ablation in patients undergoing coronary artery bypass and cardiac valve surgery

Surgical ablation of atrial fibrillation (AF) in conjunction with other cardiac surgery is now a class I guideline recommendation. Multiple studies have demonstrated that the concomitant surgical ablation of AF can be performed safely and effectively during valve and coronary artery bypass grafting (CABG) resulting in a return to sinus rhythm postoperatively and improved long‐term results. However, the surgical ablation of AF at the time of other cardiac surgery is performed less often than it should be, especially in patients undergoing CABG and aortic valve surgery. Randomized‐controlled trials designed to determine the effect of treating AF concomitantly with other cardiac surgical procedures have lacked long‐term follow up, but multiple, large observational studies have demonstrated an improved quality of life, a decrease in long‐term strokes, and improved late survival in patients who undergo AF ablation. However, the potential survival benefit of concomitant AF ablation was not addressed by either the Society of Thoracic Surgery or American Association for Thoracic Surgery guideline committees. Left atrial appendage closure is an important part of the surgical ablation of AF as it significantly reduces the long‐term risk of stroke following cardiac surgery and improves the success of AF treatment. In this study, we update the electrophysiology and surgical community on the recommended surgical techniques for AF ablation and its effect on perioperative morbidity, perioperative mortality, as well as its long‐term effects on stroke, quality of life, and survival.     

Impact of Chronic Obstructive Pulmonary Disease on Procedural Outcomes and Quality of Life in Patients with Atrial Fibrillation Undergoing Catheter Ablation

Impact of COPD on Atrial Fibrillation Ablation. Background : Chronic obstructive pulmonary disease (COPD) is a risk factor for atrial fibrillation (AF). The aim of this study was to investigate the impact of COPD on outcomes of catheter ablation in patients with AF in terms of recurrence and quality of life (QoL). Methods : In this prospective study, 550 consecutive patients with symptomatic, medication‐refractory AF underwent first catheter ablation. Patients were classified into those with COPD (group 1, n = 54) and those without COPD (group 2, n = 496). Patients were followed up for atrial tachyarrhythmia (ATa) recurrence for at least 24 months. The Medical Outcomes Study SF‐36 Health Survey was used to assess QoL at baseline and 24 months after ablation. Results : After a single ablation, 24 patients in group 1 (44.4%) and 142 in group 2 (28.6%) had ATa recurrence during a mean follow‐up of 31.4 ± 4.8 months (P = 0.016). The second ablation was performed in 19 patients (35.2%) from group 1 and in 109 patients (22.0%) from group 2 (P = 0.029). Multivariate logistic analysis showed that nonparoxysmal AF (P = 0.013, OR = 1.767, 95% CI: 1.129–2.765) as well as the presence of COPD (P = 0.029, OR = 1.951, 95% CI: 1.070–3.557) was the independent predictor for higher ATa recurrence. Moreover, patients in group 1 had significantly lower baseline scores on all SF‐36 Health Survey subscales. At 24‐month follow‐up, both mental component summary and physical component summary scores improved markedly in group 1 and 2. Conclusions : Although the presence of COPD predicted higher recurrence after single‐catheter ablation in AF patients, significant improvements in QoL were observed in the postablation COPD population. (J Cardiovasc Electrophysiol, Vol. 24, pp. 148‐154, February 2013)     

Long-term clinical efficacy and risk of catheter ablation for atrial fibrillation in the elderly

Introduction: The number of elderly patients with atrial fibrillation (AF) is increasing rapidly, and the safety and efficacy of catheter ablation in this demographic group has not been established. Methods: Over a 7‐year period we studied 1,165 consecutive patients undergoing 1,506 AF ablation procedures using a consistent ablation protocol that included proximal ostial pulmonary vein (PV) isolation and focal ablation of non‐PV AF triggers. Outcome was analyzed for three distinct age groups: <65 years (group 1; n = 948 patients), 65–74 years (group 2; n = 185 patients), and ≥75 years (group 3; n = 32 patients) based on the age at the initial procedure. Results: There was no significant difference in AF control (89% in group 1, 84% in group 2, and 86% in group 3, P = NS) during a mean follow‐up of 27 months. Major complication rates were also comparable (1.6% in group 1, 1.7% in group 2, 2.9% in group 3, P = NS) between the three groups. There was no difference in the left atrial size, percentage with left ventricular ejection fraction <50%, or percentage with paroxysmal versus more persistent forms of atrial fibrillation. However, older patients were more likely to be women (20% in group 1, 34% in group 2, and 56% in group 3, P < 0.001) and have hypertension and/or structural heart disease (56% in group 1 vs 68% in group 2 vs 88% in group 3; P < 0.001). There was a strong trend demonstrating that older patients were less likely to undergo repeat ablation (26% vs 27% vs 9%) to achieve AF control and more likely to remain on antiarrhythmic drugs (20% vs 29% vs 37%; P < 0.05). Conclusions: Elderly patients with AF undergoing catheter ablation therapy are represented by a higher proportion of women and have a higher incidence of hypertension/structural heart disease. To achieve a similar level of AF control, there appears to be no increased risk from the ablation procedure, but elderly patients are more likely to remain on antiarrhythmic drugs.     

Ablation of focal atrial fibrillation

In the past decades management of atrial fibrillation (AF) has been based mainly on drug therapy. New insights into the pathophysiology of AF initiation and maintenance have provided the background for the design of catheter based procedures. The crucial role of the pulmonary veins (PVs) as triggers of AF paved the way for successful mapping and ablation. Electrical isolation of all PVs using the circular mapping approach has been shown to be an effective procedure, with reported success rates around 70 to 80% in most series. Intracardiac echocardiography is a very helpful adjunctive tool to facilitate correct positioning of the circular catheter at the PV-left atrial junction, as well as to monitor energy delivery and assist transseptal left atrial access. PV stenosis is a potential serious complication, occurring in around 2% of cases. It presents mainly with respiratory symptoms, although it is frequently asymptomatic. Spiral computed tomography is a reliable non-invasive method for imaging the PVs and can be used to screen patients for PV stenosis after radiofrequency ablation. In symptomatic patients, PV dilatation and stenting is the preferred treatment approach.The possibility of curing AF represents a major breakthrough in invasive cardiac electrophysiology. Isolation of all PVs is a very solid endpoint for successful ablation and should be pursued in all patients. It seems to be associated with high success rates over long term follow-up. Future refinements in catheter technology should provide simpler and faster procedures and render catheter ablation of AF more widespread and accepted.     

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)