Maria Matiello

Incidence of pulmonary vein stenosis in patients submitted to atrial fibrillation ablation: a comparison of the Selective Segmental Ostial Ablation vs the Circumferential Pulmonary Veins Ablation.

Introduction: Pulmonary vein (PV) stenosis is an important complication of the AF ablation and could be underestimated if their assessment is not systematically done. Selective Segmental Ostial Ablation (SSOA) and Circunferential Pulmonary Veins Ablation (CPVA) have demonstrated efficacy in atrial fibrillation (AF) treatment. In this study the real incidence of PV stenosis in patients (pts) submitted to both SSOA and CPVA was compared.Methods: Those pts with focal activity and normal left atrial size were submitted to SSOA, remaining pts were submitted to CPVA to treat refractory, symptomatic AF. Contrast enhanced magnetic resonance angiography (MRA) was routinely performed in all patients 4 months after the procedure.Results: A series of 73 consecutive patients (mean age of 51 ± 11 years; 75% male) were included. SSOA was performed in 32 patients, and the remaining 41 patients underwent to CPVA, obtaining similar efficacy rates (72% vs 76% arrythmia free probability at 12 months; log rank test p = NS). Six patients had a significant PV stenosis, all in SSOA group none in CPVA group (18.8% vs 0%; p = 0.005). All patients were asymptomatic and the stenosis was detected in routine MRA. No predictors of stenosis has been identified analysing patient procedure characteristics.Conclusion: PV stenosis is a potential complication of SSOA not seen in CPVA. The study confirms than MRA is useful for identifying patients with asymptomatic PV stenosis.

Left atrial posterior wall isolation does not improve the outcome of circumferential pulmonary vein ablation for atrial fibrillation: a prospective randomized study.

Background—Ablation of the pulmonary veins (PVs) for atrial fibrillation treatment is often combined with linear radiofrequency lesions along the left atrium (LA) to improve the success rate. The study was designed to assess the contribution of LA posterior wall isolation to the outcome of circumferential pulmonary vein ablation (CPVA). Methods and Results—CPVA consisted of continuous radiofrequency lesions encircling both ipsilateral PVs plus an ablation line along the mitral isthmus. Patients were then randomized into 2 groups. In the first group, superior PVs were connected by linear lesions along the LA roof (CPVA-1 group). In the second group, the LA posterior wall was isolated by adding a second line connecting the inferior aspect of the 2 inferior PVs (CPVA-2 group). The study included 120 patients (53±11 years, 77% male, 60% paroxysmal atrial fibrillation, LA of 41.3±5.4 mm, 46% with hypertension, and 22% with structural heart disease). After a single ablation procedure and a mean follow-up of 10±4 months, 24 (40%) patients of the CPVA-1 group had atrial fibrillation recurrences and 3 (5%) had new-onset LA flutter. In the CPVA-2 group, recurrences were due to atrial fibrillation episodes in 23 patients (38%) and LA flutter in 4 (7%). Freedom from arrhythmia recurrences was not statistically different in the CPVA-1 group as compared with the CPVA-2 group (log rank P=0.943). Conclusion—Isolation of the LA posterior wall did not increase the success rate of CPVA.

Left ventricular systolic dysfunction by itself does not influence outcome of atrial fibrillation ablation.

Aims The objective of the study was to analyse the influence of left ventricular (LV) ejection fraction (EF) on the outcomes of atrial fibrillation (AF) ablation after a first procedure. Pre-procedural predictors of recurrences after AF ablation can be useful for patient information and selection of candidates. The independent influence of LV systolic dysfunction on recurrence rate has not been studied. Methods and results A case–control study (1:1) was conducted with a total of 72 patients: 36 cases (depressed LVEF) and 36 controls (normal LVEF). Patients were matched by left atrial diameter (LAD), the presence of arterial hypertension, and other variables that might influence the results (age, gender and paroxysmal vs. persistent AF). There were no statistical differences in the variables used to perform the matching. Patients with depressed LVEF had higher LV end diastolic diameter (55.6 ± 6.2 vs. 52.4 ± 5.5, P = 0.03), higher LV end systolic diameter (40.3 ± 6.9 vs. 32.6 ± 4.3, P < 0.001), lower LVEF (41.4 ± 8.0 vs. 63.1 ± 5.5, P < 0.001) and were more likely to have structural heart disease. After a mean follow-up of 16 ± 13 months, survival analysis for AF recurrences showed no differences between patients with depressed vs. normal LVEF (50.0 vs. 55.6%, log rank = 0.82). Cox regression analysis revealed LAD to be the only variable correlated to recurrence [OR 1.11 (1.01–1.22), P = 0.03]. Analysis at 6 months showed a significant increase in LVEF (43.23 ± 7.61 to 51.12 ± 13.53%, P = 0.01) for the case group. Conclusion LV systolic dysfunction by itself is not a predictor of outcome after AF ablation. LAD independently correlates with outcome in patients with low or normal LVEF.

Left Atrial Contractility is Preserved After Successful Circumferential Pulmonary Vein Ablation in Patients with Atrial Fibrillation

Introduction: Circumferential pulmonary vein ablation (CPVA) for atrial fibrillation (AF) consists of creating extensive lesions in the left atrium (LA). The aim of the study was to evaluate changes in LA contractility after ablation and their relationship with procedure outcome.

Circumferential pulmonary vein ablation: does use of a circular mapping catheter improve results? A prospective randomized study.

BACKGROUND The best method for performing atrial fibrillation (AF) ablation is still under debate. The importance of using a circular mapping (CM) catheter for assessing isolation of the pulmonary vein (PV) antrum on the outcome of the procedure has not been clearly established. OBJECTIVE The purpose of this study was to evaluate whether use of a CM catheter improves the arrhythmia-free proportion after circumferential pulmonary vein ablation (CPVA). METHODS A series of 146 consecutive patients (83% males, age 53 +/- 10 years, 53% paroxysmal AF) were randomized to two ablation strategies. In both groups, ipsilateral PV encirclement was performed until disappearance or dissociation of the local electrogram within the surrounded area. In the first group, only the radiofrequency catheter was used to both map and ablate (CPVA group, n = 73). In the other group, a CM catheter was added to assess the electrical activity of the PV antrum (CPVA-CM group, n = 73). An ablation line along the left atrial roof was also created in all patients. RESULTS Procedural and fluoroscopic times were longer in the CPVA-CM group (P <.05). Severe procedure-related complications occurred in 1 (1.4%) patient in the CPVA group and in 3 (4.1%) patients in the CPVA-CM group (P = .317). After mean follow-up of 9 +/- 3 months, 31 (42.5%) patients in the CPVA group and 47 (64.4%) patients in the CPVA-CM group were arrhythmia-free without antiarrhythmic medication (P = .008). CONCLUSION Use of a CM catheter to ensure isolation of the PV antrum improved the success of CPVA but increased some procedural requirements.

Evolución de la mejora en los resultados y las complicaciones de la ablación por catéter de la fibrilación auricular: aprendizaje, técnicas y metodología

INTRODUCTION AND OBJECTIVES The outcomes of atrial fibrillation ablation procedures vary widely between different centers. Our objective was to analyze the results and complications of this procedure in our center and identify factors predicting the efficacy and safety of atrial fibrillation ablation. METHODS In total, 726 atrial fibrillation ablation procedures were performed in our center between 2002 and 2009. Beginning in January 2008, a protocol for anticoagulation and conscious sedation was systematically applied. Outcomes and complications could therefore be compared in 2 well-differentiated groups: group A included 419 procedures performed prior to 2008 and group B included 307 procedures completed after 2008 using the new protocol. RESULTS During an average follow-up of 8.7 months, 60.9% of patients were arrhythmia-free after one or repeat procedures. After only 1 procedure, the success rate was 41% and significantly higher in group B (51.6% vs 35.2% in group A; P=.001). There were 31 major complications (4.2%), 26 in group A (6.2%) and 5 in group B (1.6%) (P=.002). The implementation of the new protocol was an independent predictor of the absence of complications (odds ratio=0.406; 95% confidence interval, 0.214-0.769; P<.006). CONCLUSIONS Systematic application of an anticoagulation and conscious sedation protocol is associated with improved results and fewer complications of atrial fibrillation ablation. Factors not evaluated in the present study, such as operator experience and ongoing improvements in atrial fibrillation ablation technology, could have influenced these findings.

Cooled-tip vs. 8 mm-tip catheter for circumferential pulmonary vein ablation: comparison of efficacy, safety, and lesion extension

AIMS In many laboratories, cooled-tip catheters have replaced 8 mm-tip catheters due to their theoretical advantage of achieving larger lesions and avoiding charring. However, direct comparisons between the catheters in the subset of atrial fibrillation (AF) ablation are scarce. The aim of this study was to compare the efficacy, safety, and lesion extension created by 8 mm-tip vs. cooled-tip catheter with different energy settings for circumferential pulmonary vein ablation (CPVA). METHODS AND RESULTS A series of 221 consecutive patients with symptomatic AF were included in the study. Circumferential pulmonary vein ablation was performed using an 8 mm-tip catheter (55 W, 50 degrees C) in 90 patients (Group 1), a cooled-tip (30 W, 45 degrees C) in 42 (Group 2), and a cooled-tip (40 W, 45 degrees C) in 89 (Group 3). In a subgroup of 60 patients, troponin I (TpnI), creatinine kinase, and myoglobin values were obtained before and at 12 and 24 h after ablation. At 1 year follow-up, the probability of being arrhythmia-free after a single procedure was 53, 35, and 55% in patients from Groups 1, 2, and 3, respectively. Ablation with a cooled-tip catheter at 30 W led to a higher recurrence rate (P = 0.030) and was identified in Cox regression analysis as an independent predictor of AF recurrence (HR, 1.713; 95% CI, 1.02-2.90; P = 0.045). There were no differences in intra-procedure complications (2.2 vs. 5.6 vs. 4.9%, P = 0.542). The myocardial lesion according to TpnI was smaller in Group 2 (P = 0.02). CONCLUSION The cooled-tip catheter at 30 W was less efficacious than both the 8 mm catheter and the cooled-tip with a 40 W power setting.

Left Atrial Posterior Wall Isolation Does Not Improve the Outcome of Circumferential Pulmonary Vein Ablation for Atrial FibrillationCLINICAL PERSPECTIVE

Background—Ablation of the pulmonary veins (PVs) for atrial fibrillation treatment is often combined with linear radiofrequency lesions along the left atrium (LA) to improve the success rate. The study was designed to assess the contribution of LA posterior wall isolation to the outcome of circumferential pulmonary vein ablation (CPVA). Methods and Results—CPVA consisted of continuous radiofrequency lesions encircling both ipsilateral PVs plus an ablation line along the mitral isthmus. Patients were then randomized into 2 groups. In the first group, superior PVs were connected by linear lesions along the LA roof (CPVA-1 group). In the second group, the LA posterior wall was isolated by adding a second line connecting the inferior aspect of the 2 inferior PVs (CPVA-2 group). The study included 120 patients (53±11 years, 77% male, 60% paroxysmal atrial fibrillation, LA of 41.3±5.4 mm, 46% with hypertension, and 22% with structural heart disease). After a single ablation procedure and a mean follow-up of 10±4 months, 24 (40%) patients of the CPVA-1 group had atrial fibrillation recurrences and 3 (5%) had new-onset LA flutter. In the CPVA-2 group, recurrences were due to atrial fibrillation episodes in 23 patients (38%) and LA flutter in 4 (7%). Freedom from arrhythmia recurrences was not statistically different in the CPVA-1 group as compared with the CPVA-2 group (log rank P=0.943). Conclusion—Isolation of the LA posterior wall did not increase the success rate of CPVA.

Left Atrial Posterior Wall Isolation Does Not Improve the Outcome of Circumferential Pulmonary Vein Ablation for Atrial FibrillationCLINICAL PERSPECTIVE: A Prospective Randomized Study

Background—Ablation of the pulmonary veins (PVs) for atrial fibrillation treatment is often combined with linear radiofrequency lesions along the left atrium (LA) to improve the success rate. The study was designed to assess the contribution of LA posterior wall isolation to the outcome of circumferential pulmonary vein ablation (CPVA). Methods and Results—CPVA consisted of continuous radiofrequency lesions encircling both ipsilateral PVs plus an ablation line along the mitral isthmus. Patients were then randomized into 2 groups. In the first group, superior PVs were connected by linear lesions along the LA roof (CPVA-1 group). In the second group, the LA posterior wall was isolated by adding a second line connecting the inferior aspect of the 2 inferior PVs (CPVA-2 group). The study included 120 patients (53±11 years, 77% male, 60% paroxysmal atrial fibrillation, LA of 41.3±5.4 mm, 46% with hypertension, and 22% with structural heart disease). After a single ablation procedure and a mean follow-up of 10±4 months, 24 (40%) patients of the CPVA-1 group had atrial fibrillation recurrences and 3 (5%) had new-onset LA flutter. In the CPVA-2 group, recurrences were due to atrial fibrillation episodes in 23 patients (38%) and LA flutter in 4 (7%). Freedom from arrhythmia recurrences was not statistically different in the CPVA-1 group as compared with the CPVA-2 group (log rank P=0.943). Conclusion—Isolation of the LA posterior wall did not increase the success rate of CPVA.