Long-term Patient and Health Service Outcomes of Ablation and Antiarrhythmic Drugs in Atrial Fibrillation: A Comparative Systematic Review

Atrial fibrillation (AF) is a prevalent problem worldwide and a common cause of hospitalization, poor quality of life, and increased mortality. Although several treatments are used, the use of ablation and antiarrhythmic drug therapy has increased in the past decade. However, debate continues on the most suitable option for heart rhythm control in patients. Previous studies have largely focused on short-term outcome effects of these treatments. This systematic review aims to determine the effect of ablation compared to antiarrhythmic drugs for AF on long-term patient and health service outcomes of mortality, hospitalization, and quality of life. Three databases were systematically searched-studies were included if they reported long-term outcomes of more than 12 months comparing the 2 treatments. Title and abstract screening and subsequent full-text screening was done by 2 reviewers. Data were extracted from the final studies identified. The details of the search were recorded according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses report. A total of 2224 records were identified. After removing duplicates and screening the titles and abstracts, 68 records required full-text screening. Finally, 12 papers were included in the analysis. Eight studies reported mortality indicating ablation was superior, 2 studies reported hospitalization with opposing outcomes, and 5 quality of life studies indicating ablation was a better treatment. In studies assessing long-term outcomes, beyond 12 months, following ablation or rhythm control drugs for AF, most found a lower risk of death and greater improvement in quality of life in the ablation group.

Catheter ablation in Asian patients with atrial fibrillation and hypertrophic cardiomyopathy: electrophysiological characteristics of recurrence and long-term clinical outcomes

Background

Catheter ablation (CA) is a treatment strategy for atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM). We investigated the electrophysiological characteristics of recurrence in a tertiary referral center and compared long-term clinical outcomes after CA therapy with patients who did not undergo CA.

Methods

Patients with HCM and AF who underwent CA (group 1, n = 60) or pharmacological treatment (group 2, n = 298) between 2006 and 2021 were enrolled in this study. The baseline characteristics and electrophysiological characteristics of group 1 patients were examined to elucidate the reason for the recurrence of AF after CA therapy. The clinical results of the patients in Group 1 and Group 2 were compared using a propensity score (PS)-matched method.

Results

The most common cause of recurrence was pulmonary vein reconnection (86.5%), followed by non-pulmonary vein triggers (40.5%), cavotricuspid isthmus flutter (29.7%), and atypical flutter (24.3%). Thyroid disease (HR, 14.713; P < 0.01), diabetes (HR, 3.074; P = 0.03), and non-paroxysmal AF (HR, 4.012; P = 0.01); these factors independently predicted recurrence. After the first recurrence, patients who underwent repeat CA showed a better arrhythmia-free state (74.1%) than those who underwent drug escalation therapy (29.4%, P < 0.01). After matching, PS-group 1 patients showed significantly better outcomes in all-cause mortality, heart failure hospitalization, and left atrial reverse remodeling than PS-group 2 patients.

Conclusions

Patients who underwent CA showed better clinical outcomes than those who underwent drug therapy. The main predictors of recurrence were thyroid disease, diabetes, and non-paroxysmal AF.

Clinical outcomes and structural remodelling after ablation of atrial fibrillation in heart failure with mildly reduced or mid-range ejection fraction

AIMS

The efficacy of catheter ablation (CA) on clinical outcomes and cardiac structural remodelling in atrial fibrillation (AF) patients with HF with mildly reduced or mid-range ejection fraction (HFmrEF) remains unclear. We aimed to compare the efficacy of CA with medical therapy (MT) in AF patients with HFmrEF.

METHODS AND RESULTS

We retrospectively screened a total of 36 879 patients with AF between 2005 and 2020. Patients who were initially diagnosed with echocardiography-proved HFmrEF and had follow-up echocardiography were enrolled. After applying propensity score matching in a 1:1 ratio, 72 patients treated by CA (Group 1) and 72 patients receiving MT (Group 2) were taken into further analysis. The co-morbidities were similar between the two groups, except for hyperlipidaemia. After a mean follow-up duration of 58.9 ± 42.6 months, Group 1 had a lower HF hospitalization and all-cause mortality compared with Group 2 (hazard ratio (HR), 0.089 [95% confidence interval (CI), 0.011-0.747]; P = 0.026 and HR, 0.121 [95% CI, 0.016-0.894]; P = 0.038, respectively). As for cardiac structural remodelling, the Group 1 had a better improvement in left ventricular ejection fraction (LVEF) and a more decreased left atrium (LA) diameter than Group 2 (+25.0% ± 18.0% vs. +6.2% ± 21.6%, P = <0.0001 and -1.6 ± 4.7 mm vs. +1.5 ± 8.2 mm, P = 0.008, respectively).

CONCLUSIONS

In patients with HFmrEF and AF, CA of AF could reduce both HF hospitalization and all-cause mortality as compared with those with MT. A significant improvement in LVEF and decrease in LA diameter were also observed in the CA group. Early rhythm control with CA should be taken into consideration in patients with HFmrEF and AF.

Long-term Outcome of Patients with Long-standing Persistent Atrial Fibrillation undergoing Ablation Guided by a Novel High-Density Panoramic Mapping System - A Propensity Score Matching Study

Background

Catheter ablation is a current therapeutic approach for atrial fibrillation (AF). However, its efficacy for long-standing persistent AF remains suboptimal.

Objective

The purpose of this study was to test the hypothesis that a panoramic mapping system (CARTOFINDER, Biosense Webster) can guide pulmonary vein (PV) isolation and additional potential AF drivers.

Methods

A total of 76 patients with nonparoxysmal AF referred for ablation guided by a novel high-density panoramic mapping system with CARTOFINDER were prospectively enrolled. Of this cohort, 40 patients (52.6%) had long-standing persistent AF (CARTOFINDER group). We then retrospectively screened the patients with long-standing persistent AF undergoing conventional PV isolation and elimination of non-PV triggers during the contemporary period (conventional group). They were matched at a 1:2 ratio (40 patients in group 1 received ablation guided by CARTOFINDER; 80 patients in group 2 receiving conventional PV isolation and elimination of non-PV triggers).

Results

During follow-up, patients in group 1 had a lower recurrence AF rate than those in group 2 (P = .040). There was no difference in recurrence of atrial flutter (P = .996) and atrial tachycardia (P = .525). In Cox proportional hazards regression analysis, AF duration and PV isolation along with AF driver ablation using a panoramic mapping system with CARTOFINDER both were independent predictors of recurrent AF after catheter ablation of long-standing persistent AF.

Conclusion

Identification of the potential drivers in long-standing AF is crucial. Compared with conventional PV isolation and elimination of non-PV triggers, ablation guided by a high-density panoramic mapping system (CARTOFINDER) might have a better outcome in patients with long-standing persistent AF.

Effectiveness and Safety of Cryoablation in Patients With Atrial Fibrillation Episodes of <24 h Duration: A Propensity-Matched Analysis

Background: Paroxysmal atrial fibrillation (AF) is closely related to pathophysiologic processes and clinical outcomes. However, it is uncertain whether cryoablation of pulmonary veins isolation is effective and safe for patients with symptomatic and drug refractory AF episodes of <24-h duration.

Methods: The patients were designed into Group A (253 patients with paroxysmal AF episodes of <24-h duration) and Group B (253 patients with paroxysmal AF lasting for 24 h or longer) on a 1:1 basis by identical propensity scores. Mortality, stroke/transient ischemic attack (TIA), and complications relevant to the cryoablation procedure were compared, and recurrence of atrial tachyarrhythmia was analyzed for clinical independent predictors.

Results: The rate of atrial tachyarrhythmia recurrence was 21.74% in Group A and 30.04% in Group B, respectively (P = 0.042). At 12-month follow-up from the procedure, lower incidences of stroke/TIA endpoint of the patients were observed in Group A compared with Group B by Kaplan–Meier analysis [HR 0.34 (0.13–0.87), P = 0.025]. No significant differences in mortality and complications relevant to the cryoablation procedure were observed between Group A and Group B. Moreover, adjusted multivariable Cox regression analysis showed that <24-h paroxysmal AF type (HR 0.644, 95% CI: 0.455–0.913, P = 0.014) and left atrium diameter (LAD) (>40 mm) (HR 1.696, 95% CI: 1.046–2.750, P = 0.032) were independently associated with the incidence of recurrence of atrial tachyarrhythmia in the study.

Conclusion: Our findings indicated that <24-h paroxysmal AF type was obviously associated with an increased success rate of cryoablation and reduced incidence of stroke/TIA during the follow-up period. Therefore, there is superior effectiveness and similar safety in patients with AF episodes of <24-h duration compared with patients with longer paroxysmal AF duration.

Impact of sinus rhythm maintenance on major adverse cardiac and cerebrovascular events after catheter ablation of atrial fibrillation: insights from AF frontier ablation registry

The impact of catheter ablation for atrial fibrillation (AF) on cardiovascular events and mortality is controversial. We investigated the impact of sinus rhythm maintenance on major adverse cardiac and cerebrovascular events after AF ablation from a Japanese multicenter cohort of AF ablation. We investigated 3326 consecutive patients (25.8% female, mean age 63.3 ± 10.3 years) who underwent catheter ablation for AF from the atrial fibrillation registry to follow the long-term outcomes and use of anti coagulants after ablation (AF frontier ablation registry). The primary endpoint was a composite of stroke, transient ischemic attack, cardiovascular events, and all-cause death. During a mean follow-up of 24.0 months, 2339 (70.3%) patients were free from AF after catheter ablation, and the primary composite endpoint occurred in 144 (4.3%) patients. The AF nonrecurrence group had a significantly lower incidence of the primary endpoint (1.8 per 100 person-years) compared with the AF recurrence group (3.0 per 100 person-years, p = 0.003). The multivariate analysis revealed that freedom from AF (hazard ratio 0.61, 95% confidence interval 0.44-0.86, p = 0.005) was independently associated with the incidence of the composite event. In the multicenter cohort of AF ablation, sinus rhythm maintenance after catheter ablation was independently associated with lower rates of major adverse cardiac and cerebrovascular events.

Novel model-based point scoring system for predicting stroke risk in atrial fibrillation patients: Results from a nationwide cohort study with validation

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This study used rigorous statistical method to construct the novel AF-CA-Stroke score and demonstrated that the novel stroke risk stratification tool had significantly higher discrimination abilities than conventional scores.

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This study exhibited that the status of various age stratifications and receiving AF ablation shall be considered in managing AF treatment.

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Based on the AF-CA-Stroke score, around 80–85% patients may take benefits form AF ablation procedures with lower stroke risks, and they may not be necessary to receive oral anticoagulants after receiving successful AF ablations.

Background

The stroke risk scoring system for atrial fibrillation (AF) patients can vary considerably based on patients’ status while receiving ablation. This study aimed to demonstrate a novel scoring system for stroke risk stratification based on the status of catheter ablation.

Methods

First, 787 patients with AF undergoing ablation were matched according to age, sex, and underlying diseases with the same number of patients not undergoing ablation using the propensity-score (PS)-matched cohort. Multivariate Cox model-derived coefficients were used to construct a simple point-based clinical model using the PS-matched cohort. Thereafter, the novel model (AF-CA-Stroke score) was validated in a nationwide AF cohort.

Results

The AF-CA-Stroke score was calculated based on age (point = 5), ablation status (point = 4), prior history of stroke (point = 4), chronic kidney disease (point = 2), diabetes mellitus (point = 1), and congestive heart failure (point = 1). Risk function to predict the 1-, 5-, 10-year absolute stroke risks was reported. The estimated area under the receive operating characteristic curve of the AF-CA-Stroke score in the PS-matched cohort was 0.845 (95% confidence interval: 0.824–0.865) to predict long-term stroke. A validation study showed that discrimination abilities in the AF-CA-Stroke scores were significantly higher than those in the CHADS₂/CHA₂DS_2-VASc scores. The best cut-off value of the AF-CA-Stroke score to predict future strokes was ≥ 5.

Conclusions

This novel model-based point scoring system effectively identifies stroke risk using clinical factors and AF ablation status of patients with AF. Various age stratifications and AF ablation should be considered in AF management.

Major adverse cardiovascular events and mortality after catheter ablation in Japanese patients with atrial fibrillation: The Fushimi AF Registry

BACKGROUND

The impact of catheter ablation (CA) on the long-term clinical outcomes in atrial fibrillation (AF) are unclear due to limited cohort investigations.

METHODS

The Fushimi AF Registry is a community-based prospective survey of patients with AF in Fushimi-ku, Kyoto, Japan. Of 4465 patients enrolled between March 2011 and July 2019, analyses were performed on 2639 patients (492 patients who underwent CA and 2147 patients who received standard rhythm- and/or rate-control drug therapy at baseline). We compared the baseline characteristics and the incidence of major adverse cardiovascular events (MACE: the composite of cardiovascular death, heart failure hospitalization, myocardial infarction, ischemic stroke or systemic embolism), and all-cause mortality during the follow-up using propensity score matching.

RESULTS

After entering 20 covariates in the current matching analysis, 342 patients who underwent CA and 342 matched patients who received drug therapy, with a median follow-up of 1865 days, were included. The patients who underwent CA were significantly associated with lower incidence of MACE (hazard ratio (HR) 0.56, 95% confidential interval (CI) 0.36-0.86; P = 0.0077), and all-cause mortality (HR 0.47, 95% CI 0.29-0.75; P = 0.0016).

CONCLUSION

CA was associated with lower incidences of MACE and all-cause mortality for patients with AF as compared with those who received drug therapy. The most common event of MACE in patients who underwent CA was heart failure hospitalization.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/index.htm UNIQUE IDENTIFIER: UMIN000005834.

Virtual reality informative aids increase residents' atrial fibrillation ablation procedures-related knowledge and patients' satisfaction

BACKGROUND

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and increasing numbers of patients receive AF ablation nowadays. Therefore, in the cardiology division, residents need to be familiar with the AF ablation procedure-related knowledge for primary care. This study evaluated the baseline residents and patients' self-efficacy to the AF ablation procedure-related knowledge, developed the specific virtual reality (VR) informative aids, and evaluated the effects of VR training and resident-led VR aids-based patient education on their self-efficacy, in the aspects of familiarity, confidence and anxiety, and satisfaction.

METHODS

From 2019, April to 2020, April, this 1-year prospective prestudy and poststudy was undergone in the cardiology division. Between 2019, April and 2019, December, the experienced physicians were invited to develop VR informative aids for AF ablation procedure-related knowledge. Between January 2020 and April 2020, newly developed VR informative aids were implemented in the educational program of training rotated residents for giving patient education.

RESULT

A total of 20 residents and 32 patients were enrolled. The baseline self-reported self-efficacy and knowledge scores were relatively low among rotated residents and their patients. In addition to the high level of satisfaction, self-efficacy and knowledge scores of residents and their patients were increased after VR aids-based training and resident-led patient education. Higher degree of improvement in self-efficacy was noted among patients with depression/anxiety history than those without history. The follow-up assessments among residents showed that the positive effects of VR aids were sustained until 2 weeks later.

CONCLUSION

Overall, residents and patients reported that the VR aids increase the effectiveness of patient education, achieve the purpose of a paperless environment, and motivate them to recommend it to others. The implementation of resident-to-patient education has a positive impact on trainees and patients understanding about AF ablation procedures-related knowledge.

Catheter ablation for atrial fibrillation is associated with reduced risk of mortality in the elderly: a prospective cohort study and propensity score analysis

BACKGROUND

It is unclear whether catheter ablation (CA) for atrial fibrillation (AF) affects the long-term prognosis in the elderly. This study aims to evaluate the relationship between CA and long-term outcomes in elderly patients with AF.

METHODS

Patients more than 75 years old with non-valvular AF were prospectively enrolled between August 2011 and December 2017 in the Chinese Atrial Fibrillation Registry Study. Participants who underwent CA at baseline were propensity score matched (1:1) with those who did not receive CA. The outcome events included all-cause mortality, cardiovascular mortality, stroke/transient ischemic attack (TIA), and cardiovascular hospitalization.

RESULTS

Overall, this cohort included 571 ablated patients and 571 non-ablated patients with similar characteristics on 18 dimensions. During a mean follow-up of 39.75 ± 19.98 months (minimum six months), 24 patients died in the ablation group, compared with 60 deaths in the non-ablation group [hazard ratio (HR) = 0.49, 95% confidence interval (CI): 0.30-0.79, P = 0.0024]. Besides, 6 ablated and 29 non-ablated subjects died of cardiovascular disease (HR = 0.25, 95% CI: 0.11-0.61, P = 0.0022). A total of 27 ablated and 40 non-ablated patients suffered stroke/TIA (HR = 0.79, 95% CI: 0.48-1.28, P = 0.3431). In addition, 140 ablated and 194 non-ablated participants suffered cardiovascular hospitalization (HR = 0.84, 95% CI: 0.67-1.04, P = 0.1084). Subgroup analyses according to gender, type of AF, time since onset of AF, and anticoagulants exposure in initiation did not show significant heterogeneity.

CONCLUSIONS

In elderly patients with AF, CA may be associated with a lower incidence of all-cause and cardiovascular mortality.

Thromboembolic Risk of Cessation of Oral Anticoagulation Post Catheter Ablation in Patients With and Without Atrial Fibrillation Recurrence

Cessation of oral anticoagulation (OAC) is common after the first 3 months of catheter ablation of atrial fibrillation (AF); however, thromboembolic risk has not been defined in patients with and without AF recurrence (RAF vs NRAF) post ablation. We identified 796 patients who discontinued OAC at 3 months post AF ablation from January 2015 to May 2018 in our center. Regular follow-up was performed to detect RAF, collect medication management and thromboembolic and major bleeding events. CHA₂DS₂-VASc score was 1.79 ± 1.50; 547 (68.7%) patients were at intermediate and high risk (i.e., CHA₂DS₂-VASc score ≥1 in male patients, or ≥2 in female patients); 169 (21.2%) were RAF. During 29.2±12.2 months follow-up, the incidence rate of thromboembolism was 1.62 per 100 patient-year (7 in 431 years) in RAF, 0.33 per 100 patient-year (5 in 1,503 years) in NRAF. After adjusting for potential confounding factors, RAF was associated with more 3.5-fold higher rate of thromboembolism compared with NRAF (adjusting HR, 4.488; 95% CI, 1.381 to 14.586). Rate of thromboembolism was even higher in patients with intermediate and high risk (2.16 per 100 patient-year [7 in 323 years] vs 0.38 per 100 patient-year [4 in 1,043 years], aHR, 5.807; 95% CI, 1.631 to 20.671). In multivariate logistic regression analysis, RAF was the only independent predictor of thromboembolism (4.837 [1.498 to 15.621], p = 0.008). In conclusion, cessation of OAC in NRAF may be reasonable, especially for patients with the contraindications for continuing OAC; however, cessation of OAC appeared unsafe in RAF with a high-risk stroke profile because of high incidence rate of thromboembolism.

Does Catheter Ablation Lower the Long-Term Risk of Stroke and Mortality in Patients with Atrial Fibrillation? A Concise Review of the Current State of Knowledge

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and carries a significant risk of morbidity and mortality. Multiple trials have highlighted the benefit of catheter ablation over medical therapy in restoring sinus rhythm and improving quality of life. Whether it reduces long-term risk of stroke and mortality is still unclear.

We performed a literature search using the PubMed database to review the current state of knowledge regarding the long-term outcomes of stroke and mortality in ablated patients compared to patients who receive medical therapy. Our review mainly consisted of recent randomized controlled trials and large observational studies. 

Results from large observational studies show that catheter ablation significantly reduces the risk of stroke in high-risk patients and mortality compared to medical therapy. However, randomized controlled trials have only demonstrated a mortality benefit in patients with comorbid systolic heart failure. In patients with paroxysmal AF, ablation therapy significantly limits the progression to persistent AF and has a higher efficacy in restoring sinus rhythm. Maintenance of sinus rhythm is the most important factor associated with lower long term risk of stroke and mortality.

Large randomized controlled trials similar to the Catheter Ablation Versus Anti-arrhythmic Drug Therapy for Atrial Fibrillation (CABANA) trial are still needed to clarify whether catheter ablation is superior over medical therapy in improving the long-term outcomes of stroke and mortality.

Improvement in renal and endothelial function after catheter ablation in patients with persistent atrial fibrillation

BACKGROUND

Cardiovascular events in patients with atrial fibrillation (AF) can be lowered by catheter ablation. We hypothesized the underlying mechanism was improvement in renal and endothelial function corresponding to AF burden, and investigated whether restoration of sinus rhythm (SR) after ablation affected these functions according to AF type.

METHODS AND RESULTS

We prospectively measured estimated glomerular filtration rate (eGFR), urinary albumin-to-creatinine ratio (UACR), and reactive hyperemia index (RHI) in 358 consecutive patients with AF before and 6 and 12 months after the ablation. For each AF type [paroxysmal AF (PAF), n = 229, and persistent AF (PeAF), n = 129], we evaluated changes in these markers and influence of chronic kidney disease (CKD). The eGFR and natural logarithm-transformed (ln) UACR improved at 6 months in the PeAF group (68.7 ± 18.7-71.8 ± 18.9 mL/min/1.73 m², p = 0.003 and 3.1±1.6 to 2.8±1.5, p < 0.001, respectively) and remained unchanged in the PAF group. Among the PeAF patients, recurrent AF was identified in 41, but only transiently in 38 patients. PeAF at baseline independently predicted increased eGFR [odds ratio (OR)=2.13, 95 % confidence interval (CI) 1.35-3.40, p = 0.001] and decreased UACR (OR=1.94, 95 % CI 1.05-3.58, p = 0.033). In the PeAF patients with CKD, ln-RHI significantly increased at 6 months after the ablation, and the change (Δ) in ln-RHI was significantly correlated with the ΔeGFR (r=0.35, p = 0.03).

CONCLUSIONS

SR restoration after ablation was associated with an improved eGFR and UACR in PeAF patients, but not PAF patients. In PeAF patients with CKD, an improved endothelial function after ablation was associated with an improved renal function.

Opposite effect of ablation on early/late-phase thromboembolic incidence in patients with atrial fibrillation: A meta-analysis on more than 100 000 individuals

Background

Atrial fibrillation (AF) is an important risk factor for thromboembolic events, for which catheter ablation represents an effective therapy for rhythm control. Intuitively, ablation may reduce the incidence of thromboembolism, but data is quite limited.

Hypothesis

Catheter ablation was associated with the fewer risk of thromboembolism compared with nonablation in patients with AF.

Methods

A systematic search was performed in PubMed, EMBASE, the Web of Science, and the Cochrane Library from inception to September 2019. Random‐effects model was used to estimate the risk ratios (RR) for the thromboembolic events between the ablation and nonablation groups.

Results

Twenty‐five studies (12 randomized controlled trials and 13 observational studies) with 104 687 participants were included. Pooled analysis suggested that ablation was associated with a 35% lower risk of total thromboembolic events compared to nonablation group (RR = 0.65; 95% CI, 0.51‐0.82; P = .0003). When separated into early‐phase (<30 days) and late‐phase (>30 days) events, ablation was associated with an increased early‐phase thromboembolism (RR = 1.96; 95% CI, 1.35‐2.83; P = .0004) but a decreased late‐phase thromboembolism (RR = 0.75; 95% CI, 0.63‐0.90; P = .002). Subgroup analysis according to different study types found similar results were found in observation studies, but not in RCT studies because the sample size was too small to be conclusive.

Conclusions

In patients with AF, catheter ablation was associated with a fewer risk of overall and late‐phase thromboembolism in comparison with nonablation. However, over the early postoperative period, catheter ablation was associated with the double higher risk of thromboembolic events.

Ablation Versus Medical Therapy for Atrial Fibrillation in the Elderly: A Propensity Score-Matched Comparison

Background

Whether ablation therapy reduces the risk of death and embolic events in elderly patients with atrial fibrillation (AF) remains unclear.

Material/Methods

AF patients ≥65 years old receiving either catheter ablation or non-ablation therapy at 2 tertiary and 2 non-tertiary hospitals in Beijing from November 2009 to December 2012 were enrolled. Patients were followed up every 6 months for information on treatment and clinical event occurrence. A propensity score matching algorithm produced comparable 2 groups of patients treated with ablation or non-ablation. Rates of a composite of all-cause death, non-fatal stroke, and peripheral embolism were the primary outcomes. Each composite component and major bleeding were the secondary outcomes.

Results

There were 596 ablated patients and 1144 patients with non-ablation therapy enrolled. Propensity score algorithm matched 347 comparable pairs of patients. Patient characteristics variables were well balanced. During 523.5 and 497.5 patient-years follow-up, respectively, ablation therapy was associated with a significant lower risk of experiencing the primary composite outcome (hazard ratio [HR]=0.40; 95% confidence interval [CI]: 0.19–0.85), all-cause death (HR=0.13 95% CI: 0.04–0.43), and major bleeding (HR=0.23; 95% CI: 0.12–0.67), without apparent heterogeneity by age, sex, and AF type, and for risk score subgroups.

Conclusions

In this propensity-matched elderly sample, ablation therapy was associated with lower risk of composite outcome consisting of all-cause death, non-fatal stroke, and peripheral embolism, and therefore might be an alternative to conservative therapy.

Efficacy of catheter ablation of focal sources in persistent atrial fibrillation

INTRODUCTION

Recent studies suggest that atrial fibrillation (AF) is maintained by electrical activity arising from focal sources. We sought to test whether catheter ablation that targets focal sources can improve on current ablation protocols for persistent AF.

METHODS AND RESULTS

In patients with persistent AF whose AF did not terminate with pulmonary vein (PV) isolation, the left atrium was mapped with a 20-pole high-density mapping catheter using CARTO^® 3 navigation. If a site demonstrated centrifugal activation over at least three consecutive cycles, it was deemed a focal source and ablated. If AF remained, defragmentation was performed until AF was terminated. Freedom from atrial tachyarrhythmia was compared between the study patients and propensity score matched historical controls who had undergone conventional stepwise ablation. Of the 68 study patients, 2.9 ± 1.9 focal sources were identified in 60 patients. Focal sources displayed transient centrifugal activation patterns for a median of six consecutive cycles. Total radiofrequency duration was shorter in the study group (62 ± 16 minutes vs. 75 ± 24 minutes, P = 0.0003). During a 1-year follow-up period, 39 (57%) and 26 (38%) patients were free from atrial tachyarrhythmias in the absence of antiarrhythmic drugs in the study and control groups, respectively (hazard ratio: 1.85, 95% confidence interval: 1.17-2.96, P = 0.009). Improvement of clinical outcome was mainly driven by a decrease in recurrence of atrial tachycardia in the study patients (22% vs. 40%, P = 0.047).

CONCLUSION

The results of this study suggest that focal sources are appropriate ablation targets in addition to the PVs in persistent AF.

Should We Perform Catheter Ablation for Asymptomatic Atrial Fibrillation?

Since the original description of atrial fibrillation ablation, numerous studies have demonstrated the superiority of catheter ablation over pharmacological therapy for maintenance of sinus rhythm in patients with both paroxysmal and persistent atrial fibrillation. However, to date, no randomized studies have been powered to demonstrate a mortality or stroke reduction benefit of rhythm control with catheter ablation over a rate control strategy. The results of such ongoing studies are not expected until 2018 or 2019. Thus, the only indication for atrial fibrillation ablation in recent guidelines has been the presence of symptoms. However, up to 40% of an atrial fibrillation population may be asymptomatic. In 2017, in the absence of randomized studies, are there nevertheless data that support atrial fibrillation ablation in asymptomatic patients?

Catheter Ablation of Atrial Fibrillation: An Overview for Clinicians

Catheter ablation (CA) of atrial fibrillation (AF) is currently one of the most commonly performed electrophysiology procedures. Ablation of paroxysmal AF is based on the elimination of triggers by pulmonary vein isolation (PVI), while different strategies for additional AF substrate modification on top of PVI have been proposed for ablation of persistent AF. Nowadays, various technologies for AF ablation are available. The radiofrequency point-by-point ablation navigated by electro-anatomical mapping system and cryo-balloon technology are comparable in terms of the efficacy and safety of the PVI procedure. Long-term success of AF ablation including multiple procedures varies from 50 to 80%. Arrhythmia recurrences commonly occur, mostly due to PV reconnection. The recurrences are particularly common in patients with non-paroxysmal AF, dilated left atrium and the "early recurrence" of AF within the first 2-3 post-procedural months. In addition, this complex procedure can be accompanied by serious complications, such as cardiac tamponade, stroke, atrio-esophageal fistula and PV stenosis. Therefore, CA represents a second-line treatment option after a trial of antiarrhythmic drug(s). Good candidates for the procedure are relatively younger patients with symptomatic and frequent episodes of AF, with no significant structural heart disease and no significant left atrial enlargement. Randomized trials demonstrated the superiority of ablation compared to antiarrhythmic drugs in terms of improving the quality of life and symptoms in AF patients. However, nonrandomized studies reported additional clinical benefits from ablation over drug therapy in selected AF patients, such as the reduction of the mortality and stroke rates and the recovery of tachyarrhythmia-induced cardiomyopathy. Future research should enable the creation of more durable ablative lesions and the selection of the optimal lesion set in each patient according to the degree of atrial remodeling. This could provide better long-term CA success and expand indications for the procedure, especially among the patients with non-paroxysmal AF.

Safety of catheter ablation for atrial fibrillation in patients with intracranial hemorrhage

BACKGROUND

The safety of anticoagulation and radiofrequency catheter ablation (RFCA) in patients with atrial fibrillation (AF) and a history of intracranial hemorrhage (ICH) remains unclear. We investigated the risks and benefits of this approach in AF patients with a history of ICH.

PATIENTS AND METHODS

The ICH group included 45 AF patients with a history of ICH who underwent RFCA. Five of these patients were excluded because ICH occurred spontaneously after cerebral infarction. The control group included 80 individuals who presented for AF ablation and did not have a history of ICH. Two controls were matched for each study group patient in terms of sex, age (±2 years), type of AF, and procedure date.

RESULTS

Patients in the ICH group had higher CHADS₂ (1.7 ± 1.3 vs. 1.1 ± 1.2, p < 0.05), CHA₂DS₂-VASc (2.6 ± 1.7 vs. 1.9 ± 1.6, p < 0.05), and HAS-BLED scores (2.5 ± 1.0 vs. 1.1 ± 1.0, p < 0.001). All participants in both groups underwent successful RFCA. The incidence of ICH during follow-up (1 vs. 0, p = 0.333) was similar between the ICH and control groups. AF-free survival between the two groups was not significant (log-rank p = 0.283) within the first 3 months, but was significant (log-rank p = 0.011) within 48 months of RFCA. History of ICH was the only independent predictor of AF recurrence according to univariate Cox regression analysis.

CONCLUSION

In AF patients with a history of ICH, AF ablation with a standard anticoagulation strategy is safe and does not seem to be associated with an increased risk of hemorrhage.

Catheter ablation of atrial fibrillation is associated with reduced risk of stroke and mortality: A propensity score-matched analysis

BACKGROUND

Catheter ablation reduces recurrence of atrial fibrillation and improves quality of life. Only few studies have assessed the effect of catheter ablation on long-term outcomes.

OBJECTIVE

The purpose of this study was to assess the association between catheter ablation and risk of stroke and mortality in patients with atrial fibrillation.

METHODS

Using the computerized database of the largest health maintenance organization in Israel, we identified all adults hospitalized with a primary diagnosis of atrial fibrillation between January 1, 2005, and December 31, 2015. Of them, a total of 969 individuals who underwent catheter ablation during the same admission were matched, on the basis of the propensity of having ablation, with 3772 individuals who did not undergo catheter ablation during the same period. The cohort was followed for the occurrence of stroke or transient ischemic attack (TIA) and mortality until June 30, 2016.

RESULTS

Overall, 3953 (83.4%) of patient in both groups had a CHA₂DS₂VASc score of 2 or greater. The incidence rate of stroke/TIA was 2.10 and 3.26 per 100 person-years in the ablation group and the nonablation group, respectively. The crude hazard ratio [HR] for stroke/TIA was 0.61 (95% confidence interval [CI] 0.48-0.79) in the ablation group compared with the nonablation group. The results were similar after controlling for CHA₂DS₂-VASc score (HR 0.58; 95% CI 0.43-0.72). The adjusted HRs for stroke alone, TIA alone, and mortality were 0.62 (95% CI 0.47-0.82), 0.47 (95% CI 0.20-0.78), and 0.57 (95% CI 0.47-0.66), respectively.

CONCLUSION

Catheter ablation of atrial fibrillation is associated with a decreased risk of stroke/TIA and mortality in predominantly patients with a high CHA₂DS₂-VASc score.

The Cost Effectiveness of LAA Exclusion

Left atrial appendage (LAA) exclusion strategies are increasingly utilized for stroke prevention in lieu of oral anticoagulants. Reductions in bleeding risk and long-term compliance issues bundled with comparable stroke prevention benefits have made these interventions increasingly attractive. Unfortunately, healthcare funding remains limited. Comparative cost economic analyses are therefore critical in optimizing resource allocation. In this review we seek to discourse the cost economics analysis of LAA exclusion over available therapeutic alternatives (warfarin and the new oral anticoagulants (NOACs)). .

2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the management of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia. Both the incidence and prevalence of AF are increasing, and the burden of AF is becoming huge. Many innovative advances have emerged in the past decade for the diagnosis and management of AF, including a new scoring system for the prediction of stroke and bleeding events, the introduction of non-vitamin K antagonist oral anticoagulants and their special benefits in Asians, new rhythm- and rate-control concepts, optimal endpoints of rate control, upstream therapy, life-style modification to prevent AF recurrence, and new ablation techniques. The Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology aimed to update the information and have appointed a jointed writing committee for new AF guidelines. The writing committee members comprehensively reviewed and summarized the literature, and completed the 2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the Management of Atrial Fibrillation. This guideline presents the details of the updated recommendations, along with their background and rationale, focusing on data unique for Asians. The guidelines are not mandatory, and members of the writing committee fully realize that treatment of AF should be individualized. The physician's decision remains most important in AF management.

Novel perspectives on arrhythmia-induced cardiomyopathy: pathophysiology, clinical manifestations and an update on invasive management strategies

Arrhythmia-induced cardiomyopathy is a partially or completely reversible form of myocardial dysfunction due to sustained supraventricular and ventricular arrhythmias. Asynchrony, rapid cardiac rates and rhythm irregularities are the main factors involved in the development of the disease. The reversible nature of arrhythmia-induced cardiac dysfunction allows only for a retrospective diagnosis of the disease once cardiac function is restored following heart rate control. A high level of suspicion is needed to make a diagnosis at an early stage and prevent further progression of the disease. Although reversible, arrhythmia-induced cellular and molecular changes may remain, increasing the risk for sudden death even when normal ejection fraction is restored as well as causing rapid deterioration of cardiac function and development of heart failure symptoms if arrhythmia recurs. Appropriate management based on a combination of pharmacologic and nonpharmacologic strategies to achieve rate control and prevent arrhythmia recurrence is pivotal to avoid further cardiac function deterioration and to control symptoms, significantly reducing the risk of heart failure and sudden cardiac death.

Long-term stroke rates after catheter ablation or antiarrhythmic drug therapy for atrial fibrillation: a meta-analysis of randomized trials

BACKGROUND

Atrial fibrillation (AF) is an independent risk factor for ischemic stroke and is associated with increased risk of death. Randomized studies suggest improved quality of life for patients with AF after successful catheter ablation compared to antiarrhythmic drug therapy. The value of ablation in long-term risk of ischemic stroke, however, has not been assessed. We conducted a meta-analysis to determine whether AF ablation reduces the long-term risk of stroke compared to antiarrhythmic drug therapy in randomized controlled trials.

METHODS & RESULTS

PubMed and the Cochrane Central Register were searched for randomized trials from January 1990 to December 2014 comparing AF catheter ablation to drug therapy. The results are reported as risk differences (RDs) and 95% CI. Thirteen trials were analyzed with 1097 patients treated by catheter ablation and 855 patients received antiarrhythmic drug therapy. Overall, seven patients (0.64%) in the catheter ablation group had ischemic stroke or transient ischemic attacks vs. two patients (0.23%) in the drug therapy group. No difference was shown in the rate of stroke or transient ischemic attack between ablation and drug therapy (RD: 0.003, 95% CI: -0.006 to 0.012, P = 0.470), and no evidence of heterogeneity was observed (I (2) = 0, P = 0.981). No potential publication bias was found. There was also no difference in mortality between the two groups (RD: -0.004, 95% CI: -0.014 to 0.006, P = 0.472).

CONCLUSIONS

This meta-analysis of randomized controlled trials showed similar rates of ischemic stroke or transient ischemic attack and death in AF patients undergoing catheter ablation compared to drug therapy. A larger prospective randomized trial to confirm this finding is warranted.

Optimization Of Stroke Prophylaxis Strategies In Nonvalvular AF -Drugs, Devices Or Both?

Atrial fibrillation (AF) is the most common cardiac arrhythmia with the prevalence increasing over time. AF probably afflicts ≥2% of worldwide adult population and increases with age.[1-3] In the Framingham Heart Study, the lifetime risk of having at least one episode of AF for 40-year-old men and women was 26% and 23% respectively.[4].

Catheter Ablation of Atrial Fibrillation in U.S. Community Practice--Results From Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF)

Background

The characteristics of patients undergoing atrial fibrillation (AF) ablation and subsequent outcomes in community practice are not well described.

Methods and Results

Using the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF), we investigated the prevalence and impact of catheter ablation of AF. Among 9935 patients enrolled, 5.3% had previous AF ablation. Patients with AF ablation were significantly younger, more frequently male, and had less anemia, chronic obstructive pulmonary disease, and previous myocardial infarction (P<0.05 for all analyses) than those without previous catheter ablation of AF. Ablated patients were more likely to have a family history of AF, obstructive sleep apnea, paroxysmal AF, and moderate-to-severe symptoms (P<0.0001 for all analyses). Patients with previous ablation were more often in sinus rhythm on entry into the registry (52% vs. 32%; P<0.0001). Despite previous ablation, 46% in the ablation group were still on antiarrhythmic therapy. Oral anticoagulation was prescribed in 75% of those with previous ablation versus 76% in those without previous ablation (P=0.5). The adjusted risk of death (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.52 to 1.18; P=0.2) and cardiovascular (CV) hospitalization (HR, 1.06; 95% CI, 0.90 to 1.26; P=0.5) were similar in both groups. Patients with incident AF ablation had higher risk of subsequent CV hospitalization than matched patients without incident ablation (HR, 1.67; 95% CI, 1.24 to 2.26; P=0.0008).

Conclusions

In U.S. clinical practice, a minority of patients with AF are managed with catheter ablation. Subsequent to ablation, there were no significant differences in oral anticoagulation use or outcomes, including stroke/non–central nervous system embolism/transient ischemic attack or death.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01165710.

Radiofrequency catheter ablation for atrial fibrillation

Antiarrhythmic drugs are the first-line treatment for atrial fibrillation (AF); as a result, catheter ablation usually is not considered until a patient is experiencing symptomatic AF refractory to at least one antiarrhythmic medication or is intolerant to medical therapy. For these patients, catheter ablation is shown to be more effective than medical therapy for controlling AF. This article reviews catheter ablation and its indications.

Can oral anticoagulants be stopped safely after a successful atrial fibrillation ablation?

Ablations of atrial fibrillation (AF) have become more widely performed, and the strategy about long-term usage of oral anticoagulants (OACs) after catheter ablation is an important issue, especially for patients without obvious evidences of recurrences. The annual rate of thromboembolic (TE) event after catheter ablation was less than 1%. CHADS2 and CHA2DS2-VASc scores could be used to identify patients at the risk of TE events after ablations who should continue OACs regardless of the status of recurrence. Despite the improvement in understanding of AF and advancement of technology in catheter ablation, the long-term successful rates of paroxysmal and non-paroxysmal AF are around 50% and 30%, respectively. Patients with a high CHADS2 score are at a high risk of recurrence which could continuously occur after the catheter ablation without reaching a plateau. Among the patients with a CHADS2 score of ≥3, 26.9% of the recurrences happened 2 years post catheter ablation. Compared to the episodes of AF before catheter ablation, the AF episodes after ablation procedures are less symptomatic and shorter in duration. Therefore, it may not be safe to stop OACs for patients with a high risk score since the AF episodes are difficult to be detected after ablation procedures, but remain dangerous. In conclusion, the decision about the long-term strategy of OACs should be based on patients' baseline clinical risk scores, such as CHADS2 and CHA2DS2-VASc scores, rather than the status of recurrence.

Monitoring Atrial Fibrillation After Catheter Ablation

Although catheter ablation is an effective treatment for recurrent atrial fibrillation (AF), there is no consensus on the definition of success or follow-up strategies. Symptoms are the major motivation for undergoing catheter ablation in patients with AF, however it is well known that reliance on perception of AF by patients after AF ablation results in an underestimation of recurrence of the arrhythmia. Because symptoms of AF occurrence may be misleading, a reliable assessment of rhythm outcome is essential for the definition of success in both clinical care and research trials. Continuous rhythm monitoring over long periods of time is superior to intermittent recording using external monitors to detect the presence of AF episodes and to quantify the AF burden. Today, new devices implanted subcutaneously using a minimally invasive technique have been developed for continuous AF monitoring. Implantable devices keep detailed information about arrhythmia recurrences and might allow identification of very brief episodes of AF, the significance of which is still uncertain. In particular, it is not known whether there is any critical value of daily AF burden that has a prognostic significance. This issue remains an area of active discussion, debate and investigation. Further investigation is required to determine if continuous AF monitoring with implantable devices is effective in reducing stroke risk and facilitating maintenance of sinus rhythm after AF ablation.

Mechanisms of Stroke in Atrial Fibrillation

Atrial fibrillation is the most common sustained cardiac arrhythmia and is associated with a high risk of stroke and thromboembolism. Increasing evidence suggests that the thrombogenic tendency inherent to atrial fibrillation is related to several underlying pathophysiological mechanisms, including reduced flow in the left atrium, changes in vessel walls, and changes in blood constituents. This article reviews the mechanisms of stroke, available risk stratification tools and therapies available for prevention of stroke in patients with atrial fibrillation.

Stroke in Atrial Fibrillation - Long-term Follow-up of Cardiovascular Events

The incidence of atrial fibrillation (AF) was around 1.5 per 1000 person-years in Taiwan. Systemic thromboembolism is the most severe complication of AF. Risk stratification and adequate thromboembolism prophylaxis is the cornerstone of treatment in AF patients. The CHA2DS2-VASc score is powerful in selecting "truly low-risk" patients who are not necessary to receive anticoagulation therapies. It is also useful in predicting thromboembolic events and mortality for patients undergoing AF ablation. Recently, more and more biomarkers and imaging parameters were reported to be associated with adverse events in AF patients. How could these biomarkers and imaging tools change the current strategy of stroke prevention in AF deserves further investigations.

Exploring the Potential Role of Catheter Ablation in Patients with Asymptomatic Atrial Fibrillation: Should We Move away from Symptom Relief?

Although silent atrial fibrillation (AF) accounts for a significant proportion of patients with AF, asymptomatic patients have been excluded from AF ablation trials. This population presents unique challenges to disease management. Recent evidence suggests that patients with asymptomatic AF may have a different risk profile and even worse long-term outcomes compared to patients with symptomatic AF. For the same reasons they might be more prone to side-effects of antiarrhythmic drugs, including pro-arrhythmias. The poor correlation between symptoms and AF demonstrated in several studies should caution physicians against making clinical decisions depending on symptoms. Although current guidelines recommend AF ablation only in patients with symptoms, more attention should be paid to the AF burden and a rhythm control strategy has the potential to improve morbidity and mortality in AF patients. However, limited data exist regarding the use of catheter ablation for asymptomatic AF patients. As ablation techniques have improved, AF ablation has become more widespread and complication rate decreased. As a result, referrals of asymptomatic patients for catheter ablation of AF are on the rise. In this review we discuss the many unresolved questions concerning the role of the ablative approach in asymptomatic patients with AF.

Renal Dysfunction, Stroke Risk Scores (CHADS 2 , CHA 2 DS 2 -VASc, and R 2 CHADS 2 ), and the Risk of Thromboembolic Events After Catheter Ablation of Atrial Fibrillation

Background—

There are limited data on the predictive value of stroke risk scores for thromboembolic events (TEs) after catheter ablation of atrial fibrillation (AF). Our objectives were to report the incidence of TEs after AF ablation in a large contemporary AF ablation cohort and to investigate the impact of renal dysfunction and the value of stroke risk stratification scores (CHADS 2 , CHA 2 DS 2 -VASc, and R 2 CHADS 2 ) for predicting TE after AF ablation.

Methods and Results—

Using the Leipzig Heart Center AF Ablation Registry, we documented TEs in patients undergoing radiofrequency AF catheter ablation. TE was defined as stroke, transient ischemic attack, or systemic embolism. Study population (N=2069; 66% men; 60±10 years; 62% paroxysmal AF; mean CHADS 2 , 1.2±0.9; CHA 2 DS 2 -VASc, 2.1±1.4; and R 2 CHADS 2 , 1.3±1.1) were followed up for a median 18 (Q1–Q3, 12–29) months (ie, 3078 patient-years). Overall, 31 TEs occurred, with 16 events within 30 days of ablation and 15 TEs (0.72%) during the follow-up period. On multivariate analysis, CHADS 2 ( P <0.001), R 2 CHADS 2 ( P <0.001), and CHA 2 DS 2 -VASc ( P =0.003) scores were independent predictors of TEs during follow-up, and AF recurrence conferred a nonsignificant trend for increased TE risk ( P =0.071–0.094). The CHA 2 DS 2 -VASc score further differentiated TE risk in patients with CHADS 2 and R 2 CHADS 2 0 to 1 (0.13% if CHA 2 DS 2 -VASc was 0–1 and 0.71% if CHA 2 DS 2 -VASc was >2) and had the best predictive value in patients with AF recurrences (c-index 0.894, P =0.022 versus CHADS 2 , P =0.031 versus R 2 CHADS 2 ).

Conclusions—

CHADS 2 , CHA 2 DS 2 -VASc, and R 2 CHADS 2 scores were associated with TE risk. The CHA 2 DS 2 -VASc score differentiated TE risk in the low-risk strata based on CHADS 2 and R 2 CHADS 2 scores and may be superior in the subgroup with AF recurrences.