Reduction In Atrial Fibrillation Recurrence Research Articles

Effectiveness of hybrid therapy versus radiofrequency ablation alone in decreasing recurrence after ablation of atrial fibrillation

Introduction Atrial fibrillation (AF) represents an important public health problem. Catheter ablation has emerged as effective therapy. Recurrence after ablation is still around 20–40%. The long-term use of anti-arrhythmic drugs (AAD) after AF ablation has been traditionally reported to reduce late AF recurrences; but has never been supported by randomised trials. Objective To test if routine continuation of the previously unsuccessful AAD beyond blanking period reduces AF recurrence at one year after AF ablation. Patients and method This randomised controlled clinical trial was conducted between January 2013 and January 2015 in Critical Care Medicine Department – Cairo University. Patients with symptomatic, drug refractory AF were enrolled. All patients underwent pulmonary vein isolation ± left atrial ablation according to AF type. The previously unsuccessful AAD was continued for at least 3 months after ablation, after which patients were randomised to either continue or stop that drug. Patients were regularly followed up for at least additional 9 months. The primary endpoint was reduction of AF recurrence. Secondary endpoints included identification of predictors of recurrence and rate of complications. Results Thirty-one patients with paroxysmal (80.6%) and persistent (19.4%) AF were enrolled. Pulmonary vein isolation was achieved in all patients. Seventeen patients were randomized to continue AAD (54.8%) beyond blanking period. After 12 months, there was no statistically significant difference of AF recurrence between the two groups (35.3% vs. 21.4%, P=0.46). The same was observed for paroxysmal AF patients (30.8% vs. 8.3%, P=0.32). Persistent AF and early AF recurrence were associated with late recurrence. Only 2 patients had major complications. Conclusion Routine continuation of previously unsuccessful AAD did not reduce AF recurrence, over a period of 12 months. Persistent AF and recurrence during blanking period were associated with later recurrence.

Benefits of Atrial Substrate Modification Guided by Electrogram Similarity and Phase Mapping Techniques to Eliminate Rotors and Focal Sources Versus Conventional Defragmentation in Persistent Atrial Fibrillation.

This prospective study compared the efficacy of atrial substrate modification guided by a nonlinear phase mapping technique with that of conventional substrate ablation. The optimal ablation strategy for persistent atrial fibrillation (AF) was unknown. In phase 1 study, we applied a cellular automation technique to simulate the electrical wave propagation to improve the phase mapping algorithm, involving analysis of high-similarity electrogram regions. In addition, we defined rotors and focal AF sources, using the physical parameters of the divergence and curvature forces. In phase 2 study, we enrolled 68 patients with persistent AF undergoing substrate modification into 2 groups, group-1 (n= 34) underwent similarity index (SI) and phase mapping techniques; group-2 (n= 34) received complex fractionated atrial electrogram ablation with commercially available software. Group-1 received real-time waveform similarity measurements in which a phase mapping algorithm was applied to localize the sources. We evaluated the single-procedure freedom from AF. In group-1, we identified an average of 2.6 ± 0.89 SI regions per chamber. These regions involved rotors and focal sources in 65% and 77% of patients in group-1, respectively. Group-1 patients had shorter ablation procedure times, higher termination rates, and significant reduction in AF recurrence compared to group-2 and a trend toward benefit for all atrial arrhythmias. Multivariate analysis showed that substrate mapping using nonlinear similarity and phase mapping was the independent predictor of freedom from AF recurrence (hazard ratio: 0.26; 95% confidence interval: 0.09 to 0.74; p= 0.01). Our study showed that for persistent AF ablation, a specified substrate modification guided by nonlinear phase mapping could eliminate localized re-entry and non-pulmonary focal sources after pulmonary vein isolation.

Perindopril for the prevention of atrial fibrillation recurrence after radiofrequency catheter ablation: One-year experience

Recurrence of atrial fibrillation (AF) after ablation is still high. Perindopril plays an essential role in AF induction and maintenance. We aimed to prove that perindopril (8 mg) could prevent recurrence after pulmonary vein isolation. Patients with paroxysmal AF who received radiofrequency ablation were randomized to a 3-month course of perindopril 8 mg once daily (perindopril group) or placebo (placebo group). Angiotensin-II (Ang-II) therapy and standard transthoracic echocardiography were performed. All 256patients with paroxysmal AF who received radiofrequency ablation were randomized. And we followed them for complete 1 year. The 3-month recurrence and the 1-year recurrence were compared between the 2 groups. The 3-month recurrence of AF was observed in 33 (26.19%) of 126 patients in the placebo group vs 19 (14.62%) of 130 patients who received perindopril 8 mg once daily (χ2, P = .021). One-year recurrence of AF was observed in 36 (28.5%) of 126 patients in the placebo group as compared with 21 (16.2%) of 130 patients who received perindopril after 1 year (P = .017). The κ value was 0.94 in the control group (P < .001) and 0.96 in the perindopril group (P < .001) between 3-month and 1-year recurrence. The Ang-II level was related to the left atrial distance with the reduction in AF recurrence (r = 0.17, P = .005 at 3 months; r = 0.25, P < .001 at 1 year). Perindopril is an effective and safe treatment for the prevention of AF recurrence after radiofrequency catheter ablation. This effect seems to be strongly associated with a significant decrease in Ang-II level and left atrial distance.

Abstract 12012: Relation Between Colchicine and Epicardial Adipose Tissue Volume Surrounding Left Atrium in Atrial Fibrillation Recurrence After Ablation

Background: Immediate recurrence of atrial fibrillation (AF) after AF ablation was related with inflammatory process. Colchicine treatment after AF ablation can reduce AF recurrence by suppression of such inflammatory reactions. The epicardial adipose tissue (EAT) has been shown to release activated pro-inflammatory cytokines and to associate with the development of AF. However, it is unclear whether colchicine treatment affects recurrence of AF according to EAT volume of left atrium (LA-EAT volume). The purpose of this study was to evaluate the relation between reduction of AF recurrence by colchicine treatment after AF ablation and LA-EAT volume. Methods: One hundred twenty two consecutive AF patients who underwent AF ablation and in whom multi-detector computed tomography was performed before ablation were included. Colchicine was prescribed to patients who approved colchicine treatment and was started at 0.5 mg/day for 2 weeks after AF ablation. We divided the study patients into larger LA-EAT group and smaller LA-EAT group according to the median (22.4 cm3) of LA-EAT volume. LA-EAT volume was obtained by semi-automatically tracing axial images from the bifurcation of the pulmonary artery to the coronary sinus and EAT was recognized using threshold attenuation values of -50 to -200 HU. In each group, we compared incidences of AF recurrence (AF &gt; 30 sec) in 3 months and 12 months after ablation between colchicine group and non-colchicine group. Results: Forty-two patients received colchicine. In larger LA-EAT group (&gt; 22.4 cm3) (n=60) incidence of AF recurrence in colchicine group showed lower tendency in 12 months after ablation (10.5% vs. 34.2%, p=0.06) while in smaller LA-EAT group (&lt; 22.4 cm3) (n=62), incidence of AF recurrence was similar between colchicine group and non-colchicine group (Table). Conclusion: Colchicine treatment after AF ablation may reduce mid-term AF recurrence in AF patients with larger LA-EAT volume.

Effect of Obstructive Sleep Apnea Treatment on Atrial Fibrillation Recurrence: A Meta-Analysis

ObjectivesThis study aimed to evaluate the cumulative effect of treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) on atrial fibrillation (AF) recurrence. BackgroundOSA is a known predictor for onset and recurrence of AF. The effect of treatment with CPAP on AF recurrence has been evaluated in small studies with varied outcomes. MethodsWe searched MEDLINE, EMBASE, CINAHL, Google Scholar, Cochrane Database of Systematic Reviews, and Cochrane Trials Register for relevant studies. Evaluation of AF recurrence in CPAP users and nonusers in patients with OSA was the primary outcome evaluated in this study. The secondary outcome was evaluation of AF recurrence in CPAP users and nonusers after pulmonary vein isolation (PVI). ResultsSeven prospective cohort studies with a total of 1,087 patients met the inclusion criteria. Across all patient groups, the use of CPAP was associated with a significant reduction in AF recurrence (relative risk: 0.58, 95% confidence interval: 0.51 to 0.67; heterogeneity chi-square p = 0.91, I2 = 0%). The beneficial effect of CPAP use was statistically significant in both groups of patients: those who underwent catheter ablation with PVI and those who did not undergo ablation and were managed medically. No other study covariates had any significant association with these outcomes of AF reduction. ConclusionsThe use of CPAP is associated with significant reduction in recurrence of AF in patients with OSA. This effect remains consistent and similar across patient populations irrespective of whether they undergo PVI.

WITHDRAWAL: Effect of Obstructive Sleep Apnea Treatment on Atrial Fibrillation Recurrence: A Meta-Analysis

This study aimed to evaluate the cumulative effect of treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) on atrial fibrillation (AF) recurrence. OSA is a known predictor for onset and recurrence of AF. The effect of treatment with CPAP on AF recurrence has been evaluated in small studies with varied outcomes. We searched MEDLINE, EMBASE, CINAHL, Google Scholar, Cochrane Database of Systematic Reviews, and Cochrane Trials Register for relevant studies. Evaluation of AF recurrence in CPAP users and nonusers in patients with OSA was the primary outcome evaluated in this study. The secondary outcome was evaluation of AF recurrence in CPAP users and nonusers after pulmonary vein isolation (PVI). Seven prospective cohort studies with a total of 1,087 patients met the inclusion criteria. Across all patient groups, the use of CPAP was associated with a significant reduction in AF recurrence (relative risk: 0.58, 95% confidence interval: 0.51 to 0.67; heterogeneity chi-square p = 0.91, I 2 = 0%). The beneficial effect of CPAP use was statistically significant in both groups of patients: those who underwent catheter ablation with PVI and those who did not undergo ablation and were managed medically. No other study covariates had any significant association with these outcomes of AF reduction. The use of CPAP is associated with significant reduction in recurrence of AF in patients with OSA. This effect remains consistent and similar across patient populations irrespective of whether they undergo PVI.

Fish Oil for the Reduction of Atrial Fibrillation Recurrence, Inflammation, and Oxidative Stress

BackgroundRecent trials of fish oil for the prevention of atrial fibrillation (AF) recurrence have provided mixed results. Notable uncertainties in the existing evidence base include the roles of high-dose fish oil, inflammation, and oxidative stress in patients with paroxysmal or persistent AF not receiving conventional antiarrhythmic (AA) therapy. ObjectivesThe aim of this study was to evaluate the influence of high-dose fish oil on AF recurrence, inflammation, and oxidative stress parameters. MethodsWe performed a double-blind, randomized, placebo-controlled, parallel-arm study in 337 patients with symptomatic paroxysmal or persistent AF within 6 months of enrollment. Patients were randomized to fish oil (4 g/day) or placebo and followed, on average, for 271 ± 129 days. ResultsThe primary endpoint was time to first symptomatic or asymptomatic AF recurrence lasting >30 s. Secondary endpoints were high-sensitivity C-reactive protein (hs-CRP) and myeloperoxidase (MPO). The primary endpoint occurred in 64.1% of patients in the fish oil arm and 63.2% of patients in the placebo arm (hazard ratio: 1.10; 95% confidence interval: 0.84 to 1.45; p = 0.48). hs-CRP and MPO were within normal limits at baseline and decreased to a similar degree at 6 months (Δhs-CRP, 11% vs. −11%; ΔMPO, −5% vs. −9% for fish oil vs. placebo, respectively; p value for interaction = NS). ConclusionsHigh-dose fish oil does not reduce AF recurrence in patients with a history of AF not receiving conventional AA therapy. Furthermore, fish oil does not reduce inflammation or oxidative stress markers in this population, which may explain its lack of efficacy. (Multi-center Study to Evaluate the Effect of N-3 Fatty Acids [OMEGA-3] on Arrhythmia Recurrence in Atrial Fibrillation [AFFORD]; NCT01235130).

Multicentre Trial of Fish Oil for the Reduction of Atrial Fibrillation Recurrence, Inflammation and Oxidative Stress: the Atrial Fibrillation Fish Oil Research Study

Most trials have shown a lack of efficacy of fish oil for the prevention of atrial fibrillation (AF) recurrence but have several notable limitations including potentially inadequate treatment dose, methodological issues such as the lack of a necessary blanking period following randomization, the lack of consideration of asymptomatic AF episodes, potential incomplete capture of recurrent AF episodes, concomitant use of anti-arrhythmic drugs (AAD) and no attempt to evaluate potential underlying mechanisms.

Long-term omega-3 polyunsaturated fatty acid supplementation reduces the recurrence of persistent atrial fibrillation after electrical cardioversion

Persistent atrial fibrillation (AF) is associated with a high risk of recurrence after electrical cardioversion. We examined if long-term supplementation with omega-3 polyunsaturated fatty acids in fish oils commenced >1 month prior to electrical cardioversion and continued thereafter reduces recurrence of persistent AF. This was an open-label, randomized study of 178 patients with persistent AF >1-month duration. Participants were assigned to control group (n = 87) or omega-3 group (6 g/d fish oil; n = 91) and underwent cardioversion 1 month later. Concurrent antiarrhythmic use of sotalol or amiodarone was permitted. Fish oil was continued till return of persistent AF or a maximum of 1 year. Intention-to-treat analysis was performed for the primary end point defined as the recurrence of persistent AF. Mean duration of fish oil intake was 56 days precardioversion and a total of 242 days in follow-up. Eicosapentaenoic acid and docosahexaenoic acid, the active components of fish oils, were 1.8-fold and 2.1-fold higher, respectively, in the omega-3 group compared with controls at the time of cardioversion (P <.001). At 90 days, 38.5% of the patients receiving omega-3 fatty acid supplement had AF recurrence compared with 77.5% of the controls (hazard ratio [omega-3 vs control] 0.38; 95% confidence interval 0.27-0.56; P <.001). Omega-3 intake was associated with a significant reduction in AF recurrence with or without concurrent antiarrhythmic drugs. Omega-3 polyunsaturated fatty acid supplementation commenced >1 month prior to electrical cardioversion and continued thereafter reduces the recurrence of persistent AF. Randomized controlled trials on long-term fish oil supplementation are needed to confirm these findings.

Statin use and recurrence of atrial fibrillation after successful cardioversion

Statins have important pleiotropic effects and have been shown to reduce vascular inflammation and the incidence of atrial fibrillation (AF) after cardiac surgery. The role of statins in patients with existing AF is poorly understood. We examined the effect of statins on recurrence of AF in patients after successful cardioversion. Statin use and documented recurrence of AF after successful cardioversion were evaluated in 625 patients with new onset AF who were followed prospectively in the Canadian Registry of Atrial Fibrillation. Logistic regression was used to model the effect of statin use on the recurrence of AF at 1 year while adjusting for potential confounders including concurrent medications. In a predominantly male population (62%) with median age 63 years, 12.3% were on statins at baseline. Overall, 32.5% had documented recurrence of AF at 1 year; 23.4% in patients on statins compared to 33.8% in those not on statins (P = .07). After adjustment for baseline differences and concomitant beta-blocker use, statin use was associated with a 74% reduction in AF recurrence, but only in statin users on beta-blockers (OR 0.26, 95% CI 0.10-0.66); statin users not on beta-blockers (OR 1.07, 95% CI 0.44-2.58). In an observational study of patients with new onset AF, statin use was associated with a significant 74% reduction in the odds of recurrent AF, but only in patients also taking beta-blockers. Importantly, statin without concomitant beta-blocker use was not associated with any changes in AF recurrence.

Prospective randomized study comparing amiodarone vs. amiodarone plus losartan vs. amiodarone plus perindopril for the prevention of atrial fibrillation recurrence in patients with lone paroxysmal atrial fibrillation

The purpose of this trial was to compare the long-term efficacy of low-dose amiodarone with losartan and perindopril (both combined with low-dose amiodarone) for the prevention of atrial fibrillation (AF) recurrence in patients with lone paroxysmal AF. One-hundred and seventy-seven patients with lone paroxysmal AF were randomly assigned to three treatment groups: group 1 received low-dose amiodarone alone, group 2 received low-dose amiodarone plus losartan, and group 3 received low-dose amiodarone plus perindopril. Left atrial diameter was measured with transthoracic echocardiogram at baseline and 6, 12, 18, and 24 months after randomization. The primary endpoint was the incidence of AF documented by 12-lead ECG or Holter after 14 days and within 24 months after randomization. The primary endpoint was reached in 24 patients (41%) in group 1, 11 (19%) in group 2, and 14 (24%) in group 3 (P = 0.02). The Kaplan-Meier survival analysis demonstrated a significant reduction in AF recurrence in group 2 (P = 0.006, log-rank test) as well as in group 3 (P = 0.04, log-rank test) when compared with group 1. No difference in the AF recurrence-free survival was found between group 2 and group 3. After 24 months follow-up, the left atrial diameter in group 2 and group 3 was significantly smaller than that in group 1 (36 +/- 2.3 and 35 +/- 2.4 vs. 38 +/- 2.4 mm, P < 0.001 for both comparisons). The results of this study suggest that the combination of perindopril or losartan with low-dose amiodarone is more effective than low-dose amiodarone alone for the prevention of AF recurrence in patients with lone paroxysmal AF. Adding losartan or perindopril to amiodarone can inhibit left atrial enlargement in this group of patients.