Arrhythmia-free Survival Research Articles

Catheter ablation of atrial fibrillation in very young adults: a 5-year follow-up study.

Catheter ablation is an established therapy for symptomatic atrial fibrillation (AF). However, outcome data on catheter ablation for AF in young adults is scarce. From 2005-2014, 85 consecutive young adults (mean age 31 ± 4 years; 69% men) with symptomatic paroxysmal AF (PAF, n = 52) and persistent (Pers) AF (n = 33) underwent pulmonary vein isolation (PVI) [±ablation of complex fractionated atrial electrograms/linear lesions in PVI non-responders] at our centre. Follow-up was based on outpatient visits including 24-h Holter-ECG at 3, 6 and, 12 months post ablation, and every 12 months thereafter. Recurrence was defined as any AF/atrial tachycardia episode >30s following a 3-month blanking period. Follow-up was available for 74/85 (87%) patients. After a median follow-up of 4.6 years (Q1: 2.6; Q3: 6.6) and a mean of 1.5 ± 0.6 (median 1, range 1-3) ablation procedures 84% [including 13% on previously ineffective antiarrhythmic drugs (AAD)] of patients were in stable SR. Single-procedural 1-year/5-year arrhythmia-free survival was 66% [95% confidence interval (CI): 56-78%]/44% (95% CI: 33-59%), respectively. Structural heart disease [SHD; hazard ratio (HR) 2.79 (95% CI 1.52-5.12), P = 0.001] and obesity [HR 1.10 (95% CI 1.00-1.21) per unit increase in body mass index >27 kg/m2, P = 0.05] independently predicted AF recurrence. Major complications occurred in 6/122 (4.9%) procedures (PV stenosis in 3, cardiac tamponade in 1, stroke in 1, and arterial-venous fistula in 1). In the majority of very young adults catheter ablation for AF is effective, and associated with an acceptable complication rate. SHD and obesity are predictors for AF recurrence in this population.

Durability of wide-area left atrial appendage isolation: Results from extensive catheter ablation for treatment of persistent atrial fibrillation

Extensive ablation strategies are currently performed in addition to pulmonary vein isolation (PVI) to improve the clinical outcome of patients with drug-refractory persistent atrial fibrillation (AF). Ablation of complex fractionated atrial electrograms (CFAEs), linear lesions, and/or isolation of the left atrial appendage (LAA) are thought to improve arrhythmia-free survival. The purpose of this study was to assess the durability of wide-area left atrial appendage isolation (LAAI) achieved by PVI, an anterior line, and a mitral isthmus line. Seventy-one patients with intentional or incidental LAAI during repeat catheter ablation for treatment of persistent AF were included. The initial ablation strategy was PVI. Additional ablation strategies were performed only if PVI failed to maintain stable sinus rhythm. Durability of LAAI was assessed during a subsequent ablation procedure for arrhythmia recurrences (n = 23) or a subsequent percutaneous LAA closure (n = 48). LAAI was performed after a mean of 3 ± 1 procedures. Ablation strategies included circumferential PVI in 71 patients (100%), mitral isthmus line in 64 (90%), anterior line in 60 (85%), CFAE in 27 (38%), and roof line in 13 (18%). LAAI occurred after ablation and bidirectional block of LA linear lesions in 63 patients (89%) and during extensive CFAE ablation in 8 patients (11%). After a median of 105 [61;426] days, the LAA remained electrically isolated in 52 of 71 patients (73%). Wide-area LAAI after extensive catheter ablation for persistent AF is durable in the majority of patients. The potential clinical benefit of LAAI for maintaining stable sinus rhythm requires further investigation.

The Right to Left Atrial Volume Ratio Predicts Outcomes after Circumferential Pulmonary Vein Isolation of Longstanding Persistent Atrial Fibrillation.

We aimed to identify the predictors of clinical outcomes after circumferential pulmonary vein isolation (CPVI) without any substrate modification for longstanding persistent atrial fibrillation (LSP-AF). This study retrospectively analyzed 70 consecutive LSP-AF patients who underwent an initial CPVI and were followed-up for more than 1 year. The right and left atrial volumes indexed to the body surface areas (right atrial volume index [RAVI] and left atrial volume index [LAVI]) were determined by preacquired contrast-enhanced computed tomography (CT). The %RAVI/LAVI was obtained as 100 × RAVI/LAVI. During a median follow-up period of 15 months (interquartile range, 13-19 months), 21 patients (30%) had arrhythmia recurrences after the CPVI. Antiarrhythmic drugs were continued in 34 patients (48%). In the Cox proportional hazard model, the %RAVI/LAVI was a significant positive predictor of arrhythmia recurrences (hazard ratio, 1.048; P = 0.039). A receiver-operating characteristic analysis demonstrated that at an optimal cutoff of 100.1 for the %RAVI/LAVI, the sensitivity and specificity for predicting arrhythmia recurrences were 85.7% and 71.4%, respectively. The Kaplan-Meier analysis showed that arrhythmia recurrences were less frequent in patients with a %RAVI/LAVI of <100.1 than in those with a %RAVI/LAVI of ≥100.1 (P < 0.0001), and the arrhythmia-free survival rate at 12 months was 89.7% and 45.2%, respectively. The ratio of the RAVI to LAVI on CT may be a useful predictor of clinical outcomes after CPVI of LSP-AF. LSP-AF patients with a less predominant right atrial enlargement relative to the left atrial enlargement may be good candidates for successful treatment with CPVI alone as the ablation strategy for LSP-AF.

Scar Homogenization Versus Limited-Substrate Ablation in Patients With Nonischemic Cardiomyopathy and Ventricular Tachycardia

BackgroundScar homogenization improves long-term ventricular arrhythmia–free survival compared with standard limited-substrate ablation in patients with post-infarction ventricular tachycardia (VT). Whether such benefit extends to patients with nonischemic cardiomyopathy and scar-related VT is unclear. ObjectivesThe aim of this study was to assess the long-term efficacy of an endoepicardial scar homogenization approach compared with standard ablation in this population. MethodsConsecutive patients with dilated nonischemic cardiomyopathy (n = 93), scar-related VTs, and evidence of low-voltage regions on the basis of pre-defined criteria on electroanatomic mapping (i.e., bipolar voltage <1.5 mV) underwent either standard VT ablation (group 1 [n = 57]) or endoepicardial ablation of all abnormal potentials within the electroanatomic scar (group 2 [n = 36]). Acute procedural success was defined as noninducibility of any VT at the end of the procedure; long-term success was defined as freedom from any ventricular arrhythmia at follow-up. ResultsAcute procedural success rates were 69.4% and 42.1% after scar homogenization and standard ablation, respectively (p = 0.01). During a mean follow-up period of 14 ± 2 months, single-procedure success rates were 63.9% after scar homogenization and 38.6% after standard ablation (p = 0.031). After multivariate analysis, scar homogenization and left ventricular ejection fraction were predictors of long-term success. During follow-up, the rehospitalization rate was significantly lower in the scar homogenization group (p = 0.035). ConclusionsIn patients with dilated nonischemic cardiomyopathy, scar-related VT, and evidence of low-voltage regions on electroanatomic mapping, endoepicardial homogenization of the scar significantly increased freedom from any recurrent ventricular arrhythmia compared with a standard limited-substrate ablation. However, the success rate with this approach appeared to be lower than previously reported with ischemic cardiomyopathy, presumably because of the septal and midmyocardial distribution of the scar in some patients.

Effective contact and outcome after pulmonary vein isolation innovelcircular multi-electrode atrial fibrillation ablation.

IntroductionPulmonary vein (PV) reconnection is frequently the cause of recurrence of atrial fibrillation (AF) after ablation. The second-generation gold multi-electrode ablation (Gold-MEA) catheter has a new design possibly resulting in improved lesion formation compared with its predecessor. We aimed to determine the association between effective radiofrequency applications with the Gold-MEA catheter and outcome after AF ablation.Methods50 consecutive patients with paroxysmal AF underwent Gold-MEA (PVAC GOLDTM, Medtronic Inc.) ablation. The Gold-MEA catheter was navigated to the PV ostium by fluoroscopy. Duty-cycled radiofrequency ablations were performed at all PV ostia. Lesions were considered transmural when electrode temperature was >50 °C and power >3 W for >30 seconds. After the ablation procedure, patients visited the outpatient clinic at 3‑month intervals including 24-hour Holter ECGs.ResultsMean age was 56 years. All PVs were acutely isolated with the Gold-MEA catheter. Procedure time was 111 ± 22 minutes, ablation time was 24 ± 6.7 minutes and fluoroscopy time was 20 ± 8.1 minutes. No procedure-related complications were observed. One year after ablation, 60 % of patients were still free of arrhythmia recurrences after a single PV isolation attempt. The number of transmural lesions was associated with arrhythmia-free survival: 25.0 % in <72 transmural lesions, 64.3 % in 72–108 transmural lesions and 71.4 % in >108 transmural lesions (p = 0.029).ConclusionPV isolation can be performed successfully with the Gold-MEA catheter, with a favourable safety profile. Transmurality of lesions was associated with ablation success and may improve AF ablation success.

Role of adenosine-guided pulmonary vein isolation in patients undergoing catheter ablation for atrial fibrillation: a meta-analysis.

Adenosine had been reported to unmask dormant conduction and thus identify pulmonary vein at risk of reconnection. However, the role of adjunctive adenosine infusion after pulmonary vein isolation (PVI) on long-term arrhythmia-free survival was still contentious. The purpose of the present meta-analysis was to assess the association of adenosine testing with long-term ablation success in patients with atrial fibrillation (AF) (i.e. freedom from AF recurrence). We systematically searched the electronic databases and finally included 10 studies, with 1771 patients undergoing adenosine-guided PVI and 1787 patients undergoing conventional PVI. In comparison to conventional PVI alone, adenosine-guided PVI improved the arrhythmia-free survival by 17% during a median follow-up of 12 months [relative risk (RR): 1.17; 95% confidence interval (CI): 1.07 to 1.27; P = 0.014]. Patients undergoing adenosine-guided PVI had similar fluoroscopy time to those who undergoing conventional PVI [weighted mean difference (WMD): 1.76; 95% CI: -5.66 to 9.17; P = 0.64], despite longer procedure time (WMD: 20.6; 95% CI: 0.70 to 40.50; P = 0.042). From the available data of clinical studies, adenosine-guided PVI was associated with an increased arrhythmia-free survival when compared with conventional PVI in patients undergoing catheter ablation for AF.

Serum Galectin-3 Levels Predict Recurrences after Ablation of Atrial Fibrillation.

Galectin-3 is a biomarker of fibrosis and atrial remodeling, involved in the mechanisms of initiation and maintenance of atrial fibrillation (AF). We sought to study the accuracy of galectin-3 level in predicting recurrences of AF after ablation. Serum concentrations of galectin-3 were determined in a consecutive series of patients addressed for AF ablation in our center. After a 3-month blanking period, recurrences of atrial arrhythmias were collected during the first year in all patients, using Holter monitoring at 3, 6 months and 12 months. A total of 160 patients were included, with a mean galectin-3 rate was 14.4 ± 5.6 ng/mL. At 12-month, 55 patients (34%) had reexperienced sustained atrial arrhythmia. Only higher galectin-3 level (HR = 1.07 [1.01–1.12], p = 0.02) and larger left atrial diameter (HR = 1.07 [1.03–1.12], p = 0.001) independently predicted recurrence. Patients with both galectin-3 level <15 ng/mL and left atrial diameter <40 millimeters had a 1-year arrhythmia-free survival rate − after a single procedure without anti-arrhythmic drug − of 91%, as compared with 41% in patients with galectin-3 ≥ 15 and left trial diameter ≥40 (p < 0.0001), whether AF was paroxysmal or persistent. Galectin-3 and left atrial diameters, rather than clinical presentation of AF, predict recurrences after ablation.

Five-year follow-up outcome after catheter ablation of persistent atrial fibrillation using a sequential biatrial linear defragmentation approach: What does atrial fibrillation termination during the procedure imply?

A paucity of data exists about long-term outcomes after catheter ablation of persistent atrial fibrillation (AF). The mechanisms of AF are still unclear. The purpose of this study was to evaluate the 5-year outcome after persistent AF ablation using sequential defragmentation approaches and to identify the prognostic factors. One hundred thirty-five patients with persistent AF (age 62 ± 9 years, 76 longstanding persistent AF) underwent catheter ablation using biatrial linear defragmentation approaches consisting of substrate modification for eliminating AF after pulmonary vein antrum isolation. Procedures were stopped when AF terminated; however, AF termination was not pursued after predetermined substrate modification. AF terminated in 69 patients (51%). Total procedural and fluoroscopic times were 145.4 ± 36.1 minutes and 35.1 ± 14.3 minutes, respectively. Median [25th, 75th percentiles] follow-up was 60 [26.0-64.0] months, with 1.9 ± 0.8 procedures per patient. Arrhythmia-free survival after multiple procedures was 86.8%, 73.1%, 62.6%, and 53.8% (39 patients on antiarrhythmic drug therapy) at 1, 2, 3, and 5 years, respectively. Multivariate analyses revealed that AF termination (hazard ratio [HR] 3.043, 95% confidence interval [CI] 1.605-5.767, P = .001) was the sole independent predictor of long-term arrhythmia freedom, and arrhythmia freedom at 5 years was 70.0% and 31.8% in patients with and without AF termination (P = .0007). Five-year freedom from crossover to rate control strategies was 86.5%, and AF termination (HR 3.558, 95% CI 1.171-10.812, P = .025) was also the sole predictor. Catheter ablation of persistent AF using the sequential defragmentation approach provided limited long-term freedom of arrhythmias often requiring multiple procedures. AF termination was the sole factor predicting freedom from both arrhythmia recurrence and crossover to rate control strategies during long-term follow-up.

Adenosine-Guided Pulmonary Vein Antral Isolation for Paroxysmal Atrial Fibrillation: A Randomized Study.

The prognostic significance of adenosine-mediated pulmonary vein (PV) dormant conduction and whether such conduction should be eliminated still remain controversial. This randomized study aimed to investigate whether adenosine-guided ablation of the reconnection gaps improves the long-term outcomes of pulmonary vein antral isolation (PVAI) for paroxysmal atrial fibrillation (AF). Consecutive patients with paroxysmal AF were randomly assigned to undergo (n = 80, group 1) or not (n = 81, group 2) adenosine testing following PVAI. Adenosine-mediated PV dormant conduction was unmasked in 26 patients (32.5%) of group 1. Successful elimination of the reconnection gaps was subsequently performed in all patients. During a mean follow-up period of 11.39 ± 5.10 months, 30 patients of group 1 (37.5%), and 27 patients of group 2 (33.3%) experienced arrhythmia recurrence. The Kaplan-Meier arrhythmia free survival curves failed to demonstrate any significant differences between study groups (log rank 0.217, P = 0.642). Fourteen of 26 (53.8%) patients with adenosine-mediated dormant conduction and subsequent elimination of reconnection gaps experienced AF recurrence during follow-up. On the contrary, only 16 of 54 patients without dormant conduction (29.6%) displayed arrhythmia recurrence (P = 0.049). Logistic regression analysis showed that adenosine-mediated PV reconnection (hazard ratio 0.292, 95% confidence interval 0.122-0.483; P = 0.01) was an independent predictor of AF recurrence. In this patients' cohort, adenosine-mediated PV reconnection is predictive of future arrhythmic events. Elimination of dormant conduction with additional ablation lesions does not improve the long-term outcome of the procedure compared to the standard PVAI.

Long-Term Outcomes of Catheter Ablation of Ventricular Tachycardia in Patients With Cardiac Sarcoidosis.

Catheter ablation (CA) of ventricular tachycardia (VT) in patients with cardiac sarcoidosis can be challenging because of the complex underlying substrate. We sought to determine the long-term outcome of CA of VT in patients with cardiac sarcoidosis. We enrolled 31 patients (age, 55±10 years) with diagnosis of cardiac sarcoidosis based on Heart Rhythm Society criteria and VT who underwent CA. In 23 (74%) patients, preprocedure cardiac magnetic resonance imaging and positron emission tomographic (PET) evaluation were performed. Preprocedure magnetic resonance imaging was positive for late gadolinium enhancement in 21 of 23 (91%) patients, whereas abnormal 18-fluorodeoxyglucose uptake was found in 15 of 23 (65%) cases. In 14 of 15 patients with positive PET at baseline, PET was repeated after 6.1±3.7-month follow-up. After a median follow-up of 2.5 (range, 0-10.5) years, 1 (3%) patient died and 4 (13%) underwent heart transplant. Overall VT-free survival was 55% at 2-year follow-up. Among the 16 (52%) patients with VT recurrences, CA resulted in a significant reduction of VT burden, with 8 (50%) having only isolated (1-3) VT episodes and only 1 patient with recurrent VT storm. The presence of late gadolinium enhancement at magnetic resonance imaging, a positive PET at baseline, and lack of PET improvement over follow-up were associated with increased risk of recurrent VT. In patients with cardiac sarcoidosis and VT, CA is effective in achieving long-term freedom from VT or improvement in VT burden in the majority of patients. The presence of late gadolinium enhancement at magnetic resonance imaging, a positive PET scan at baseline, or lack of improvement at repeat PET over follow-up predict worse arrhythmia-free survival.

Can ventricular tachycardia non-inducibility after ablation predict reduced ventricular tachycardia recurrence and mortality in patients with non-ischemic cardiomyopathy? A meta-analysis of twenty-four observational studies

BackgroundAt present, the role of ventricular tachycardia (VT) non-inducibility after ablation in patients with non-ischemic cardiomyopathy (NICM) remains controversial. We conducted a meta-analysis of the published literature to assess whether VT non-inducibility after ablation could predict reduced VT recurrence and mortality in patients with NICM. MethodsPubMed, ScienceDirect, and the Cochrane library were searched for studies evaluating the effects of VT non-inducibility after catheter ablation on the long-term outcome in NICM patients with sustained VT. Results were analyzed using a fixed-effect model, and the data were pooled using RevMan 5.3 software. ResultsTwenty-four observational studies were identified (736 participants, mean follow-up time: 22months). NICM patients with VT inducibility after ablation had a higher risk of VT recurrence (odds ratio [OR]=5.83, 95% confidence interval [CI] 4.07–8.37; P<0.00001) and all-cause mortality (OR=3.55, 95% CI 1.62–7.78; P=0.002) compared with VT non-inducibility. Similarly in the subgroup analysis, patients with VT inducibility showed a higher risk of VT recurrence from non-ischemic dilated cardiomyopathy (OR=3.92, 95% CI 2.36–6.50; P<0.00001) and arrhythmogenic right ventricular dysplasia/cardiomyopathy (OR=5.37, 95% CI 2.20–13.10; P=0.0002). Additionally, meta-analysis also showed that combined endo–epicardial ablation significantly reduced the risk of VT recurrence compared with endocardial-only ablation (OR=2.02, 95% CI 1.19–3.44; P=0.009; mean follow-up time: 22months). ConclusionRecent evidence has shown that VT non-inducibility after ablation is a predictor for reduced VT recurrence and mortality compared with VT inducibility in NICM patients with sustained VT. In addition, endocardial plus adjuvant epicardial ablation provides better long-term arrhythmia-free survival than endocardial ablation alone.

Pulmonary Vein Antrum Isolation in Patients With Paroxysmal Atrial Fibrillation: More Than a Decade of Follow-Up.

We report the outcome of pulmonary vein (PV) antrum isolation in paroxysmal atrial fibrillation (AF) patients over more than a decade of follow-up. A total of 513 paroxysmal AF patients (age 54±11 years, 73% males) undergoing catheter ablation at our institutions were included in this analysis. PV antrum isolation extended to the posterior wall between PVs plus empirical isolation of the superior vena cava was performed in all. Non-PV triggers were targeted during repeat procedure(s). Follow-up was performed quarterly for the first year and every 6 to 9 months thereafter. The outcome of this study was freedom from recurrent AF/atrial tachycardia. At 12 years, single-procedure arrhythmia-free survival was achieved in 58.7% of patients. Overall, the rate of recurrent arrhythmia (AF/atrial tachycardia) was 21% at 1 year, 11% between 1 and 3 years, 4% between 3 and 6 years, and 5.3% between 6 and 12 years. Repeat procedure was performed in 74% of patients. Reconnection in the PV antrum was found in 31% of patients after a single procedure and in no patients after 2 procedures. Non-PV triggers were found and targeted in all patients presenting with recurrent arrhythmia after ≥2 procedures. At 12 years, after multiple procedures, freedom from recurrent AF/atrial tachycardia was achieved in 87%. In patients with paroxysmal AF undergoing extended PV antrum isolation, the rate of late recurrence is lower than what previously reported with segmental or less extensive antral isolation. However, over more than a decade of follow-up, nearly 14% of patients developed recurrence because of new non-PV triggers.

Treatment of stand-alone atrial fibrillation with a right thoracoscopic approach employing a microwave or monopolar radiofrequency energy source: long-term results.

Minimally invasive surgery for atrial fibrillation (AF) has rapidly evolved recently. The long-term efficacy of most of these procedures is poorly known. Between 2006 and 2010, 38 drug-resistant, symptomatic patients with stand-alone AF underwent unilateral, thoracoscopic, off-pump ablation. The mean age was 60 ± 8.2 (range 42-75) years and the mean AF duration was 46 ± 62 (range 3-240) months. Sixteen patients (42%) had paroxysmal, 9 (24%) had persistent and 13 (34%) had long-standing persistent AF. A box lesion was created using a microwave (26 patients) or monopolar radiofrequency (12 patients) system. Patients were prospectively followed with repeat electrocardiograms (ECGs) and ECG Holters. Additional catheter ablation was offered to patients with recurrence of arrhythmia. All procedures were completed as planned with one conversion to sternotomy, zero mortality and minimal in-hospital complications. The mean follow-up duration was 70 ± 19 (range 20-88) months. Arrhythmia-free survival rates after the procedure were 50, 44.4, 24.1 and 10.8% at 6, 12, 36 and 60 months, respectively, with most recurrences in the first 6 months. Twelve patients underwent additional catheter ablation(s); from the last intervention, 75% of them were in sinus rhythm (SR) with a mean follow-up of 31 ± 23 (range 4-86) months. Overall, at the end of follow-up, only 3 patients were still in SR without any arrhythmia recurrence. Major complications (cerebral, peripheral embolism or bleeding) occurred in 5 patients. Unilateral, thoracoscopic AF ablation is safe and technically feasible. However, the results of the microwave and monopolar radiofrequency devices were less than satisfactory, with a gradual decline in arrhythmia-free survival over a very long-term follow-up.

Persistent Atrial Fibrillation Ablation using the Tip-Versatile Ablation Catheter

The mechanisms by which persistent atrial fibrillation (PsAF) develops are incompletely understood. Consequently, the optimal strategy for the ablative management of PsAF remains debated. Current methods are often time consuming, complex and non-reproducible. We assessed the Tip-Versatile Ablation Catheter (T-VAC) technique, a rapidly delivered, empirical technique based on the box-set concept using duty-cycled linear catheter ablation technology. Forty-four procedures in 40 patients undergoing PsAF ablation with the novel technique were prospectively entered onto a database: 27 de novo. Primary endpoint was freedom from arrhythmia at over two-year follow-up. Secondary endpoints were time to first arrhythmia recurrence, freedom from atrial fibrillation (AF) on and off antiarrhythmic drugs (AAD), procedural and fluoroscopy duration and complication rate. At mean follow-up of 33 months, absolute freedom from arrhythmia recurrence was 45% in the de novo group. Overall, at 33 (IQR 24-63) months, 60% of de novo patients were in sustained normal sinus rhythm and a further 15% reported only occasional paroxysms of AF at long-term follow-up. Procedure time was 192±25 mins, total energy delivered 2239±883s and fluoroscopy time was 60±10mins. In selected patients with persistent AF, a long-term rate of 60% arrhythmia free survival off AAD can be achieved using this novel T-VAC technique.

Association between pulmonary vein orientation and ablation outcome in patients undergoing multi-electrode ablation for atrial fibrillation

BackgroundPrevious studies reported on the impact of pulmonary vein orientation on pulmonary vein isolation (PVI) outcome in atrial fibrillation patients undergoing laser balloon PVI and point-by-point radiofrequency ablation. ObjectiveDemonstrate the association between pulmonary vein orientation and PVI outcome after multi-electrode radiofrequency ablation. Methods120 patients undergoing PVI with a circular MER catheter were included. A left atrial ECG-triggered CT was performed in all patients prior to PVI. The orientation of all pulmonary veins at the insertion into the left atrium was measured in the axial and coronal planes. pulmonary veins were classified as having a ventral/dorsal and caudal/cranial orientation depending on the pulmonary vein trunk angle as compared to the median angle. ResultsMean age was 56 years, arrhythmia-free survival after a median follow-up of 20 months was 54.2%. Left upper pulmonary vein orientation within the coronal plane was associated with arrhythmia-free survival, ranging from 58% with a cranial pulmonary vein orientation to 21% with a caudal orientation (p = 0.003). Similarly, arrhythmia-free survival was 50% in patients with a caudal orientation and 33% in patients with a cranial orientation of the left lower pulmonary vein in the coronal plane (p = 0.036). Pulmonary vein orientation in the axial plane and orientation of the right-sided pulmonary veins were not associated with arrhythmia-free survival. Multivariable analysis showed an independent association between both left upper (hazard ratio 2.8, p = 0.001) and left lower (hazard ratio 0.490, p = 0.034) pulmonary vein orientation and arrhythmia-free survival. ConclusionIn MER ablation, orientation of the left upper and caudalpulmonary veins in the coronal plane were independently associated with arrhythmia-free survival after multi-electrode PVI.

Pulmonary Vein Isolation Versus Defragmentation: The CHASE-AF Clinical Trial

BackgroundLong-term success rates using ablation for persistent atrial fibrillation (AF) are disappointing and usually do not exceed 60%. ObjectivesThis study sought to compare arrhythmia-free survival between pulmonary vein isolation (PVI) and a stepwise approach (full defrag) consisting of PVI, ablation of complex fractionated electrograms, and additional linear ablation lines in the setting of atrial tachycardias (AT) in patients with persistent AF after PVI. MethodsFrom November 2010 to February 2013, 205 patients (151 men; 61.7 ± 10.2 years of age) underwent de novo ablation for persistent AF. Subsequently, patients were prospectively randomized to either PVI alone (n = 78) or full defrag (n = 75), with 52 patients not randomized due to AF termination with the original PVI. The primary endpoint was recurrence of any AT after a blanking period of 3 months. ResultsDuring the entire study, 241 ablations were performed (mean: 1.59 in the PVI-alone group, 1.55 in the full-defrag group). With the stepwise approach, termination of AF occurred in 45 (60%) patients. However, arrhythmia-free survival did not differ whether patients underwent single or multiple procedures (p = 0.468). Procedure duration, fluoroscopy time, and radiofrequency duration were significantly longer in the full-defrag group (all p < 0.001). ConclusionsA stepwise approach aimed at AF termination does not seem to provide additional benefit over PVI alone in patients with persistent AF, but it is associated with significantly longer procedural and fluoroscopic duration as well as radiofrequency application time. (The Randomized Catheter Ablation of Persist End Atrial Fibrillation Study [CHASE-AF]; NCT01580124)

The impact of adjunctive complex fractionated atrial electrogram ablation and linear lesions on outcomes in persistent atrial fibrillation: a meta-analysis.

In persistent atrial fibrillation (PsAF), success rates for pulmonary vein isolation (PVI) alone are limited and additional substrate modification is often performed. The two most widely used substrate-based strategies are the ablation of complex fractionated atrial electrograms (CFAE) and left atrial linear ablation (LALA) at the roof and mitral isthmus. However, it is unclear whether adjunctive CFAE ablation or LALA add significant benefit to PVI alone. We performed a meta-analysis to better gauge the benefit of adjunctive CFAE ablation and LALA in PsAF. Electronic databases were systematically searched. We included studies that examined the impact of CFAE ablation or LALA in addition to a PVI-based strategy on clinical outcomes in PsAF. We included both randomized and non-randomized studies. Totally 10 studies (n = 1821) were included: 6 evaluating CFAE ablation, 3 LALA, and 1 both approaches. In comparison with PVI alone, the addition of CFAE ablation [RR 0.86; 95% confidence intervals (CI) 0.64, 1.16; P = 0.32] or LALA (RR 0.64; 95% CI 0.37, 1.09; P = 0.10) offered no significant improvement in arrhythmia-free survival. However, adjunctive CFAE ablation was associated with significant increases (P < 0.05) and LALA non-significant increases in procedure and fluoroscopy times. In PsAF, the addition of CFAE ablation or LALA, in comparison with PVI alone, offers no significant improvement in arrhythmia-free survival. Furthermore, they are associated with increases in both procedural and fluoroscopy times. The optimal ablation strategy for PsAF is currently unclear and needs further refinement.

Abstract 18417: Clinical Presentation, Cardiac Phenotype and Long Term Prognosis of Patients With Late Onset Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

Introduction: The phenotypic features and clinical course of elderly Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C) patients (age&gt; 50 years at diagnosis) is unknown. Methods: Demographic, phenotypic and genotypic data of 502 patients with ARVC diagnosis (2010 Task Force Criteria) from Johns Hopkins and Utrecht (NL) ARVD/C registries was obtained and long term clinical outcomes ascertained. Results: Late presentation was seen in 104 (21%) patients (38% with PKP2 mutation; no DSP or DSG2 mutation carrier) with 3% being ≥ 65 years at diagnosis. Sustained ventricular tachycardia (VT) is the major (43%) mode of presentation in the elderly while cardiac syncope is infrequent (p&lt;0.001). The elderly are significantly less likely to harbor a pathogenic mutation (53%; p=0.005), have precordial T wave repolarization changes (p&lt;0.001) and have lower ventricular ectopy burden (median count 1503 vs 2497; p=0.026) compared to younger patients. In the elderly, over 7±5 years of follow up, 68(65%) patients experienced sustained ventricular arrhythmias with similar (p=0.08) arrhythmia free survival at 5 years of follow up (73% vs.60% in younger). LV dysfunction and heart failure was seen in 24(32%) and 15(14%) patients respectively without need for cardiac transplantation. Male gender (OR 2.12, 95%CI (1.3-3.45); p=0.002), absence of a pathogenic mutation (OR 1.94, 95%CI (1.20, 3.12); p=0.006) and family member status (OR 2.09, 95%CI (1.24, 3.51); P=0.006) were independently associated with late presentation. In the elderly, EP study inducibility (&lt;0.001), major RV structural disease (p=0.022), absent family history (p&lt;0.001), male gender (p=0.002) and pathogenic mutation (p=0.001) were associated with increased risk of ventricular arrhythmias while ECG abnormalities and ventricular ectopy (p=0.489) were not. Conclusion: One fifth of all ARVD/C patients present after 50 years of age, often with sustained VT and are less likely to have prior syncope or identifiable pathogenic mutation. In ARVD/C, late presentation does not confer a benign prognosis and is associated with high arrhythmic risk. Electrocardiographic changes and ventricular ectopy are significantly less common in the elderly and are not associated with arrhythmic events.

Abstract 13509: A Prospective Randomized Study on the Prevalence, Characteristics, and Predictors of Pulmonary Vein Reconnections and the Clinical Outcomes Between Contact Force-Guided and Conventional Circumferential Pulmonary Vein Isolation of Atrial Fibrillation

Purpose: To prospectively investigate the differences in pulmonary vein reconnections (PVRs) and clinical outcomes between contact force (CF)-guided and conventional circumferential PV isolation (CPVI) of atrial fibrillation (AF). Methods: A total of 120 consecutive AF patients (63±10 years; 88 males) undergoing an initial CPVI were randomized to ablation with a target CF of 20g (CF-group; n=60) or that with operators blinded to the CF information (Blind-group; n=60). The right and left CPVI lines were each divided into 12 segments, and the occurrence of PVRs and CF-related parameters were evaluated in each segment. Time-dependent and adenosine-dependent PVRs were assessed twice during the procedure, just after completing the CPVI and at the end of the procedure. Results: The CF-group had significantly fewer PVRs (0.67±0.91/patient vs. 1.16±1.16/patient; P=0.007), a higher percentage of adenosine-dependent transient PVRs (60.5% vs. 28.8%; P=0.001), and lower percentage of persistent PVRs than the Blind-group. The mean CF was higher in the CF-group than in the Blind-group (Median, 18.0g vs. 16.1g; P&lt;0.001), with the most significant difference observed along the posterior right-sided PVs (P-RPVs) and anterior left-sided PVs (A-LPVs). In multiple logistic regression models, the mean CF was a negative predictor of PVRs along the P-RPVs and A-LPVs in the Blind-group (odds ratios, 0.728 and 0.786; P&lt;0.001 and 0.007), while no significant predictor was identified in the CF-group or along the anterior RPVs and posterior LPVs in the Blind-group. In the Kaplan-Meier analysis, the arrhythmia-free survival rate at 12 months was 91.2% in the CF-group (29.8% with antiarrhythmic drugs [AADs]) and 89.4% in the Blind-group (21.1% with AADs), respectively (P=0.596). Conclusions: CF-guided CPVI can reduce PVRs and result in a higher percentage of adenosine-dependent transient PVRs, and may be particularly beneficial along regions where a relatively low CF tends to be applied: the P-RPVs and A-LPVs. The comparable clinical outcomes may be due to (1) the learning curve effect obtained by the CF-guided technique, which improved the ablation electrode-tissue contact in the Blind-group, and (2) repeated provocation and elimination of dormant PV conduction.

Primary Persistent Atrial Fibrillation: A Distinct Arrhythmia Subentity of an Ablation Population.

Persistent atrial fibrillation (persAF) can occur either as a sustained arrhythmia that has progressed from initially paroxysmal AF or as primary persAF without a history of any spontaneously terminated episode. There is a paucity of data differentiating between the 2 different persAF entities. Thus, we prospectively evaluated baseline characteristics, electrophysiological features, and ablation outcome in these 2 patient cohorts. A total number of 154 consecutive persAF patients (63 ± 10 years, f = 42, longstanding persAF = 60) were characterized in terms of having primary persAF (P-persAF group) or persAF that secondarily progressed from paroxysmal AF (S-persAF group). All patients underwent de novo catheter ablation using the stepwise approach. PersAF entities were characterized by detailed patient history, sequential Holter monitoring, and reports of documented modes of AF conversion, respectively. The P-persAF group had a higher number of young patients (<50 years), a shorter AF history, and a higher number of congestive heart failure. The HATCH score did not differ between the groups. Procedural AF termination rate was significantly higher in S-persAF than in P-persAF patients (n = 55 [81%] vs. n = 58 [68%], P = 0.043). At 1-year follow-up, the arrhythmia-free survival after a single procedure was significantly lower in patients with P-persAF (26% vs. 43%, P = 0.016). Categorization to P-persAF was the strongest independent predictor of arrhythmia recurrence. P-persAF seems to be a specific arrhythmia entity that is associated with a lower AF-termination rate and a worse outcome after catheter ablation as compared to S-persAF.