Procedural complications, rehospitalizations, and repeat procedures after catheter ablation for atrial fibrillation

[Ablation for atrial fibrillation in the elderly]

Atrial fibrillation is mainly an arrhythmia among the elderly. The current ESC guideline determines that there is no justification to deny atrial fibrillation ablation to any age group; however, the guideline does not provide specific scientific data. Thus, the goal of this article is to summarize the data on efficacy and safety of atrial fibrillation ablation among elderly people and give treatment recommendations: (1) The success of atrial fibrillation ablation is the same between elderly and younger patients. (2) In cohort studies there was a trend to higher stroke rates among elderly people. (3) Negative predictors for stroke are an age >80 years, heart failure, stroke in history, or/and CHA₂DS₂-VASc score ≥6.

National Trends in Atrial Fibrillation Hospitalization, Readmission, and Mortality for Medicare Beneficiaries, 1999-2013

BACKGROUND

Data are lacking on national trends for atrial fibrillation (AF) hospitalization, particularly with regard to long-term outcomes including readmission and mortality.

METHODS

We studied all Medicare fee-for-service beneficiaries between 1999 and 2013, and we evaluated rates of hospitalization for AF, in-hospital mortality, length of stay, and hospital payments. We then evaluated rates of long-term outcomes, including 30-day readmission, 30-day mortality, and 1-year mortality. To evaluate changes in rates of AF hospitalization and mortality, we used mixed-effects models, adjusting for age, sex, race, and comorbidity. To assess changes in rates of 30-day readmission, we constructed a Cox proportional hazards model adjusting for age, sex, race, and comorbidity.

RESULTS

Adjusted rates of hospitalization for AF increased by ≈1% per year between 1999 and 2013, and although geographic variation was present, this trend was consistent nationwide. Median hospital length of stay remained unchanged at 3.0 (interquartile range 2.0-5.0) days, but median Medicare inpatient expenditure per beneficiary increased from $2932 (interquartile range $2232-$3870) to $4719 (interquartile range $3124-$7209) per stay. During the same period, the rate of inpatient mortality during AF hospitalization decreased by 4% per year, and the rate of 30-day readmission decreased by 1% per year. The rates of 30-day and 1-year mortality decreased more modestly by 0.4% and 0.26% per year, respectively.

CONCLUSIONS

Between 1999 and 2013, among Medicare fee-for-service beneficiaries, patients were hospitalized more frequently and treated with more costly inpatient therapies such as AF catheter ablation, but this finding was associated with improved outcomes, including lower rates of in-hospital mortality, 30-day readmission, 30-day mortality, and 1-year mortality.

Who Needs Catheter Ablation And Which Approach?

Catheter ablation therapy for atrial fibrillation (AF) has gained a significant role during maintenance of sinus rhythm compared to anti-arrhythmic medication. Catheter ablation techniques are also improved and progressed over years in parallel to better understanding of disease mechanisms and technological advancements. However, due to invasive nature of the therapy with its pertinent procedural risks, both appropriate patient selection and use of relevant approach should be considered by all electrophysiologists before decide to perform catheter ablation.

Safety and Clinical Outcomes of Catheter Ablation of Atrial Fibrillation in Patients With Chronic Kidney Disease

INTRODUCTION

Data regarding catheter ablation of atrial fibrillation (AF) in patients with chronic kidney disease (CKD) is limited. We therefore assessed the association of CKD with common safety and clinical outcomes in a nationwide sample of ablation recipients.

METHODS

Using MarketScan^® Commercial Claims and Medicare Supplemental Databases, we evaluated 30-day safety and 1-year clinical outcomes in patients who underwent a first AF ablation procedure between 2007 and 2011. We calculated frequency of common 30-day complications and calculated frequencies, incidence rates, and Cox proportional hazards for outcomes at 1-year postablation.

RESULTS

Of 21,091 patients included, 1,593 (7.6%) had CKD. Patients with CKD were older (64 years vs. 59 years, P < 0.001) with higher CHA₂ DS₂ -VASc scores (3.2 vs. 1.8, P < 0.001). At 30 days postablation, patients with CKD had similar rates of stroke/TIA (0.13% vs. 0.13%, P = 0.99), perforation/tamponade (3.2% vs. 3.1%, P = 0.83), and vascular complications (2.4% vs. 2.2%, P = 0.59) as patients without CKD, but were more likely to be hospitalized for heart failure (2.1% vs. 0.4%, P < 0.001). In multivariate analysis, there were no significant differences in hazards of AF hospitalization (adjusted HR: 1.02, 95%CI: 0.87-1.20), cardioversion (adjusted HR: 0.99, 95%CI: 0.87-1.12), or repeat AF ablation (adjusted HR: 0.89, 95%CI: 0.76-1.06) at 1 year.

CONCLUSIONS

Among patients selected for AF ablation, those with and without CKD had similar rates of postprocedural complications although they were more likely to be re-admitted for heart failure. CKD was not independently associated with AF hospitalization, cardioversion, and repeat ablation. These findings can inform clinical decision-making in patients with AF and CKD.

Management of Atrial Fibrillation in Elderly Adults

Driven in large part by the aging of the population and the increasing prevalence of cardiovascular comorbidities associated with atrial fibrillation (AF), there is a burgeoning epidemic of AF in elderly adults. Although there is a large body of literature to guide management of people with AF, elderly adults with AF are frequently underrepresented in clinical trials. This review provides a contemporary update on management of elderly adults with AF with a particular focus on the two main clinical challenges that AF poses: stroke risk reduction and control of symptoms. The evidence to support novel AF treatment strategies in elderly adults is reviewed, including novel oral anticoagulants and left atrial appendage closure for stroke risk reduction and catheter ablation for control of symptoms.

Atrial Fibrillation: The Science behind Its Defiance

Atrial fibrillation (AF) is the most prevalent arrhythmia in the world, due both to its tenacious treatment resistance, and to the tremendous number of risk factors that set the stage for the atria to fibrillate. Cardiopulmonary, behavioral, and psychological risk factors generate electrical and structural alterations of the atria that promote reentry and wavebreak. These culminate in fibrillation once atrial ectopic beats set the arrhythmia process in motion. There is growing evidence that chronic stress can physically alter the emotion centers of the limbic system, changing their input to the hypothalamic-limbic-autonomic network that regulates autonomic outflow. This leads to imbalance of the parasympathetic and sympathetic nervous systems, most often in favor of sympathetic overactivation. Autonomic imbalance acts as a driving force behind the atrial ectopy and reentry that promote AF. Careful study of AF pathophysiology can illuminate the means that enable AF to elude both pharmacological control and surgical cure, by revealing ways in which antiarrhythmic drugs and surgical and ablation procedures may paradoxically promote fibrillation. Understanding AF pathophysiology can also help clarify the mechanisms by which emerging modalities aiming to correct autonomic imbalance, such as renal sympathetic denervation, may offer potential to better control this arrhythmia. Finally, growing evidence supports lifestyle modification approaches as adjuncts to improve AF control.

Atrial Fibrillation Associated Genetic Variants and Left Atrial Histology: Evaluation for Molecular Sub-Phenotypes

INTRODUCTION

Genome wide association studies have identified several single nucleotide polymorphisms (SNPs) associated with atrial fibrillation (AF), but the mechanisms underlying these relationships have not yet been elucidated. Inflammation and fibrosis have been posited as important mechanisms responsible for AF. We sought to investigate the impact of SNP carrier status on inflammation and fibrosis in left atrial appendage tissue.

METHODS AND RESULTS

Carrier status of 10 AF-associated SNPs was evaluated on DNA extracted from left atrial appendage tissue in 176 individuals (120 with AF). The presence of inflammation was evaluated through visual quantification of leukocyte infiltration following hematoxylin and eosin staining, while fibrosis was quantified using picrosirius red with fast green staining. Unadjusted and adjusted linear and logistic regression models were utilized to evaluate for an association between SNP carrier status and inflammation and fibrosis. On adjusted logistic regression analysis, the rs7164883 SNP (intronic within HCN4) was associated with a reduced odds of inflammation (odds ratio: 0.42; 95% CI: 0.22-0.81, P = 0.01), and was not associated with fibrosis on adjusted linear regression analysis (β-coefficient: -0.31; 95% CI: -1.03-0.40, P = 0.40). None of the remaining SNPs exhibited significant associations with left atrial inflammation or fibrosis.

CONCLUSIONS

Among 10 AF-associated SNPs, a single genetic variant was associated with reduced left atrial inflammation, while no histologic differences were observed in the remaining 9. The known AF-associated SNPs do not appear to predispose to the development of pro-inflammatory or pro-fibrotic AF sub-phenotypes.

Persistent Atrial Fibrillation Ablation in Females: Insight from the MAGIC-AF Trial

INTRODUCTION

Atrial fibrillation (AF) ablation is less frequently performed in women when compared to men. There are conflicting data on the safety and efficacy of AF ablation in women. The objective of this study was to compare the clinical characteristics and outcomes in a contemporary cohort of men and women undergoing persistent AF ablation procedures.

METHODS AND RESULTS

A total of 182 men and 53 women undergoing a first-ever persistent AF catheter ablation procedure in The Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF) trial were evaluated. Clinical and procedural characteristics were compared between each gender. The primary efficacy endpoint was the 1-year single procedure freedom from atrial arrhythmia off anti-arrhythmic drugs. Women undergoing catheter ablation procedures were older than men (P < 0.001). The duration of AF and associated co-morbidities were similar between both genders. Single procedure drug-free atrial arrhythmia recurrence occurred in 53% of the cohort with no difference based on gender (men = 54%, women = 53%; P = 1.0). Procedural (P = 0.04), fluoroscopic (P = 0.02), and ablation times (P = 0.003) were shorter in women compared to men. Periprocedural complications and postablation improvement in quality of life were similar between men and women.

CONCLUSION

Women undergoing a first-ever persistent AF ablation procedure were older but had similar clinical outcomes and complications when compared with men.

Rhythm control in atrial fibrillation

Many patients with atrial fibrillation have substantial symptoms despite ventricular rate control and require restoration of sinus rhythm to improve their quality of life. Acute restoration (ie, cardioversion) and maintenance of sinus rhythm in patients with atrial fibrillation are referred to as rhythm control. The decision to pursue rhythm control is based on symptoms, the type of atrial fibrillation (paroxysmal, persistent, or long-standing persistent), patient comorbidities, general health status, and anticoagulation status. Many patients have recurrent atrial fibrillation and require further intervention to maintain long term sinus rhythm. Antiarrhythmic drug therapy is generally recommended as a first-line therapy and drug selection is on the basis of the presence or absence of structural heart disease or heart failure, electrocardiographical variables, renal function, and other comorbidities. In patients who continue to have recurrent atrial fibrillation despite medical therapy, catheter ablation has been shown to substantially reduce recurrent atrial fibrillation, decrease symptoms, and improve quality of life, although recurrence is common despite continued advancement in ablation techniques.

The Impact of First Procedure Success Rate on the Economics of Atrial Fibrillation Ablation

OBJECTIVES

The purpose of this study was to compare health care costs associated with repeat ablation of atrial fibrillation (AF) with health care costs associated with a successful first procedure.

BACKGROUND

Catheter ablation has become established as a rhythm control strategy for symptomatic paroxysmal and persistent AF. The economic impact of ablation is not completely understood, and it may be affected by repeat procedures performed for recurrent AF.

METHODS

The source of data was the MarketScan (Truven Health, Ann Arbor, Michigan) administrative claims dataset from April 2008 to March 2013, including U.S. patients with private and Medicare supplemental insurance. Patients who underwent an outpatient atrial ablation procedure and a diagnosis of AF were identified. Total health care cost was calculated for 1 year before and after the ablation. Patients were categorized as having undergone a repeat ablation if an additional ablation was performed in the following year.

RESULTS

Of 12,027 patients included in the study, repeat ablation was performed in 2,066 (17.2%) within 1 year. Patients with repeat ablation had higher rates of emergency department visits (43.4% vs. 32.2%; < 0.001) and subsequent hospitalization (35.6% vs. 21.5%; p < 0.001), after excluding hospitalizations for the repeat procedure. Total medical cost was higher for patients with repeat ablation ($52,821 vs. $13,412; p < 0.001), and it remained 46% higher even after excluding the cost associated with additional ablations ($19,621 vs. $13,412; p < 0.001).

CONCLUSIONS

Health care costs are significantly higher for patients with a repeat ablation for AF than for patients with only a single ablation procedure, even though both groups have similar baseline characteristics. The increased costs persist even after excluding the cost of the repeat ablation itself. These results emphasize the economic benefit of procedural success in AF ablation.

Ultrasound-Guided Transesophageal High-Intensity Focused Ultrasound Cardiac Ablation in a Beating Heart: A Pilot Feasibility Study in Pigs

Catheter ablation for the treatment of arrhythmia is associated with significant complications and often-repeated procedures. Consequently, a less invasive and more efficient technique is required. Because high-intensity focused ultrasound (HIFU) enables the generation of precise thermal ablations in deep-seated tissues without harming the tissues in the propagation path, it has the potential to be used as a new ablation technique. A system capable of delivering HIFU into the heart by a transesophageal route using ultrasound (US) imaging guidance was developed and tested in vivo in six male pigs. HIFU exposures were performed on atria and ventricles. At the time of autopsy, visual inspection identified thermal lesions in the targeted areas in three of the animals. These lesions were confirmed by histologic analysis (mean size: 5.5 mm(2) × 11 mm(2)). No esophageal thermal injury was observed. One animal presented with bradycardia due to an atrio-ventricular block, which provides real-time confirmation of an interaction between HIFU and the electrical circuits of the heart. Thus, US-guided HIFU has the potential to minimally invasively create myocardial lesions without an intra-cardiac device.

Cost-Effectiveness of Cardiac Radiosurgery for Atrial Fibrillation: Implications for Reducing Health Care Morbidity, Utilization, and Costs

In the United States (U.S.), atrial fibrillation (AF) is the second-most common cardiovascular condition after hypertension, affecting four million Americans each year. Individuals with AF are three times more likely to be hospitalized over the span of a year when compared to medically matched control groups. The considerably large clinical population of individuals with AF mandates that the cost-effectiveness and efficacy of current treatment regimens for AF have egregious implications for health care spending and public health. Unfortunately, catheter ablation for AF treatment has been shown to make only modest gains in quality-adjusted life years, has yet to demonstrate cost-utility advantages over conventional therapies for AF, and has a reported rate of recurrence for AF that is notably high. Thus, there is a major unmet clinical need for a therapeutic option to treat AF that produces more consistent and efficacious results that are cost-effective. Cardiac radiosurgery as a therapy for AF has the potential to be remarkably cost-effective and produce robust patient outcomes. CyberHeart Inc. has developed the world's first-ever cardiac radiosurgery (CRS) system designed to ablate the heart non-invasively. Procedures that ablate the heart utilizing the Cyberheart CRS system are anticipated to allow higher efficacy and more consistent results than current techniques such as catheter ablation. The aim of this study is to present the current healthcare utilization and expenditures in AF treatment, report the cost-effectiveness of catheter ablation for AF, and project the potential cost-effectiveness of cardiac radiosurgery for the treatment of AF.

Cryoballoon or radiofrequency ablation for symptomatic paroxysmal atrial fibrillation: reintervention, rehospitalization, and quality-of-life outcomes in the FIRE AND ICE trial

AIMS

The primary safety and efficacy endpoints of the randomized FIRE AND ICE trial have recently demonstrated non-inferiority of cryoballoon vs. radiofrequency current (RFC) catheter ablation in patients with drug-refractory symptomatic paroxysmal atrial fibrillation (AF). The aim of the current study was to assess outcome parameters that are important for the daily clinical management of patients using key secondary analyses. Specifically, reinterventions, rehospitalizations, and quality-of-life were examined in this randomized trial of cryoballoon vs. RFC catheter ablation.

METHODS AND RESULTS

Patients (374 subjects in the cryoballoon group and 376 subjects in the RFC group) were evaluated in the modified intention-to-treat cohort. After the index ablation, log-rank testing over 1000 days of follow-up demonstrated that there were statistically significant differences in favour of cryoballoon ablation with respect to repeat ablations (11.8% cryoballoon vs. 17.6% RFC; P = 0.03), direct-current cardioversions (3.2% cryoballoon vs. 6.4% RFC; P = 0.04), all-cause rehospitalizations (32.6% cryoballoon vs. 41.5% RFC; P = 0.01), and cardiovascular rehospitalizations (23.8% cryoballoon vs. 35.9% RFC; P < 0.01). There were no statistical differences between groups in the quality-of-life surveys (both mental and physical) as measured by the Short Form-12 health survey and the EuroQol five-dimension questionnaire. There was an improvement in both mental and physical quality-of-life in all patients that began at 6 months after the index ablation and was maintained throughout the 30 months of follow-up.

CONCLUSION

Patients treated with cryoballoon as opposed to RFC ablation had significantly fewer repeat ablations, direct-current cardioversions, all-cause rehospitalizations, and cardiovascular rehospitalizations during follow-up. Both patient groups improved in quality-of-life scores after AF ablation.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01490814.

Electrocardiographic Spectral Features for Long-Term Outcome Prognosis of Atrial Fibrillation Catheter Ablation

Atrial fibrillation (AF) is the most common arrhythmia in routine clinical practice. Despite many years of research, its mechanisms still are not well understood, thus reducing the effectiveness of AF treatments. Nowadays, pulmonary vein isolation by catheter ablation is the treatment of choice for AF resistant either to pharmacological or electrical cardioversion. However, given that long-term recurrences are common, an appropriate patient selection before the procedure is of paramount relevance in the improvement of AF catheter ablation outcome. The present work studies how several spectral features of the atrial activity (AA) from a single lead of the surface electrocardiogram (ECG) can become potential pre-ablation predictors of long-term (>2 months) sinus rhythm maintenance. Among all the analyzed spectral features, results indicated that the most significant single predictor of paroxysmal AF ablation treatment outcome was related to the amplitude of the first harmonic of the dominant frequency, providing sensitivity (Se), specificity (Sp) and accuracy (Ac) values of 90%, 42.86 and 77.78%, respectively. On the other hand, the AA harmonic structure was the most significant single predictor for persistent AF, with Se, Sp and Ac values of 100%, 54.55 and 77.27%, respectively. A logistic regression analysis, mainly based on spectral amplitudes as well as on the harmonic structure of the AA, provided a higher predictive ability both for paroxysmal AF (Se = 100%, Sp = 57.14% and Ac = 88.89%) and persistent AF (Se = 90.91%, Sp = 72.73 and Ac = 81.82%). In conclusion, the study of key AA spectral features from the surface ECG can provide a significant preoperative prognosis of AF catheter ablation outcome at long-term follow-up.

Gender, Race, and Health Insurance Status in Patients Undergoing Catheter Ablation for Atrial Fibrillation

Catheter ablation for atrial fibrillation (AF) has emerged as a popular procedure. The purpose of this study was to examine whether there exist differences or disparities in ablation utilization across gender, socioeconomic class, insurance, or race. Using the Nationwide Inpatient Sample (2000 to 2012), we identified adults hospitalized with a principal diagnosis of AF by ICD 9 code 427.31 who had catheter ablation (ICD 9 code-37.34). We stratified patients by race, insurance status, age, gender, and hospital characteristics. A hierarchical multivariate mixed-effect model was created to identify the independent predictors of AF ablation. Among an estimated total of 3,508,122 patients (extrapolated from 20% Nationwide Inpatient Sample) hospitalized with a diagnosis of AF in the United States from the year 2000 to 2012, 102,469 patients (2.9%) underwent catheter ablations. The number of ablations was increased by 940%, from 1,439 in 2000 to 15,090 in 2012. There were significant differences according to gender, race, and health insurance status, which persisted even after adjustment for other risk factors. Female gender (0.83 [95% CI 0.79 to 0.87; p <0.001]), black (0.49 [95% CI 0.44 to 0.55; p <0.001]), and Hispanic race (0.64 [95% CI 0.56 to 0.72; p <0.001]) were associated with lower likelihoods of undergoing an AF ablation. Medicare (0.93, 0.88 to 0.98, <0.001) or Medicaid (0.67, 0.59 to 0.76, <0.001) coverage and uninsured patients (0.55, 0.49 to 0.62, <0.001) also had lower rates of AF ablation compared to patients with private insurance. In conclusion we found differences in utilization of catheter ablation for AF based on gender, race, and insurance status that persisted over time.

Closed Chest Convergent Epicardial-Endocardial Ablation of Non-paroxysmal Atrial Fibrillation - A Case Series and Literature Review

The closed chest convergent procedure is a multidisciplinary approach to atrial fibrillation (AF) treatment. Epicardial posterior left atrial (PLA) ablation is performed by a cardiac surgeon using a transdiaphragmatic endoscope, immediately followed by percutaneous pulmonary vein (PV) isolation performed by a cardiac electrophysiologist. Interim outcomes for the treatment of non-paroxysmal AF (NPAF) were evaluated based on peri-procedural safety and complications, freedom from recurrent AF, and need for cardioversion or repeat catheter ablation at three, six and 12 months post-procedure. A total of 43 patients (86 % NPAF) underwent the convergent procedure. Patients were 84 % male, with mean age 58.6 ± 8.7 years. Mean AF duration was 45.4 ± 40.3 months. Pre-procedure left atrium (LA) volumetric data using cardiac magnetic resonance imaging (MRI) or computed tomography (CT) was available for 30 patients (70 %). Average LA volume was 155.5 ± 48.4 millilitres (ml); two-thirds of patients had a LA volume >130 ml. There was no operative or peri-operative mortality. Sinus rhythm (SR) was recorded at three months in 31 of 39 (79 %) patients, at six months in 24 of 27 (89 %) patients and at 12 months in nine patients. The convergent procedure is a safe and effective option for both PV isolation and PLA substrate ablation in NPAF patients. Long-term follow-up is required and randomised clinical trials warranted.

Trends and predictors of repeat catheter ablation for atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) ablation is superior to pharmacologic therapy in achieving maintenance of normal sinus rhythm in selected patient populations. However, the procedure is resource intensive, and repeat ablations are sometimes required. We examined the predictors and trends of repeat ablation using a large national administrative claims database.

METHODS

Privately insured and Medicare Advantage patients who underwent catheter ablation for AF between January 1, 2004, and September 30, 2014, were included in the study. The primary outcome was repeat AF ablation during enrollment. We examined the associations between repeat ablation and patient demographics (age, gender, socioeconomic demographics), comorbid conditions (CHA2DS2-Vasc score and Charlson index), and year of the index ablation. Cox proportional hazard models were used to identify predictors of repeat ablation.

RESULTS

We included 8,648 adult patients in the analysis. Median age was 61.0 (interquartile range [IQR] 54-68) years, and 70.9% were men. Median follow-up was 1.1 (IQR 0.5-2.3) years. A total of 1,263 patients underwent repeat ablation (14.6%) over a total of 14,280 person-years (12.1% at 1 year). The hazard ratio (HR) for repeat ablation was higher in younger patients (HR 0.75 [0.61-0.91; P < .01] for age 65-75 and 0.55 [0.4-0.75; P < .001] for age ≥ 75 compared with age 18-54), those with higher household income (HR 1.24 [1-1.54; P < .05] for household income ≥ $100,000 compared with household income < $40,000), patients treated in the south (HR 1.15 [1-1.31]; P < .05), and those on antiarrhythmic medications (HR 1.15 [1.01-1.31]; P < .05). In particular, younger patients (ages 18-54 years) continued to undergo repeat ablations over the entire follow-up period, and the cumulative rate was approximately 40% among those followed for 5 years. Clinical characteristics including those included in the CHA2DS2-Vasc score and Charlson index did not predict likelihood of repeat ablation. The rate of repeat ablation remained constant over the available follow-up.

CONCLUSION

Approximately 1 in 8 patients treated with catheter ablation for AF will undergo a second procedure within 1 year, although the rate is as high as 40% in young patients at 5 years. The rate of repeat ablation appears to be associated with demographic characteristics (younger age and higher household income) rather than medical comorbidities.

Electrophysiological Perspectives on Hybrid Ablation of Atrial Fibrillation

To overcome limitations of minimally invasive surgical ablation as a standalone procedure in eliminating atrial fibrillation (AF), hybrid approaches incorporating adjunctive endovascular catheter ablation have been proposed in recent years. The endovascular component targets residual conduction gaps and identifies additional electrophysiological targets with the goal of minimizing recurrent atrial arrhythmia. We performed a systematic review of published studies of hybrid AF ablation, analyzing 432 pooled patients (19% paroxysmal, 29% persistent, 52% long-standing persistent) treated using three different approaches: A. bilateral thoracoscopy with bipolar radiofrequency (RF) clamp-based approach; B. right thoracoscopic suction monopolar RF catheter-based approach; and C. subxiphoid posterior pericardioscopic ("convergent") approach. Freedom from recurrence off antiarrhythmic medications at 12 months was seen in 88.1% [133/151] for A, 73.4% [47/64] for B, and 59.3% [80/135] for C, with no significant difference between paroxysmal (76.9%) and persistent/long-standing persistent AF (73.4%). Death and major surgical complications were reported in 8.5% with A, 0% with B and 8.6% with C. A critical appraisal of hybrid ablation is presented, drawing from experiences and insights published over the years on catheter ablation of AF, with a discussion of the rationale underlying hybrid ablation, its strengths and limitations, where it may have a unique role in clinical management of patients with AF, which questions remain unanswered and areas for further investigation.

Meta-Analysis of Efficacy and Safety of Apixaban in Patients Undergoing Catheter Ablation for Atrial Fibrillation

BACKGROUND

The efficacy and safety of apixaban in patients undergoing catheter ablation (CA) for atrial fibrillation (AF) are little investigated.

METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and EMBASE were searched up to September 2015. Four literatures comparing apixaban with vitamin K antagonists (VKAs) were included. Data were pooled in Review Manager Software, using Mantel-Haenszel methods with a fixed-effects model. The funnel plots and Egger's test were used to examine publication bias. Heterogeneity was assessed using the I(2) test. Risk ratios (RR) and 95% confidence intervals (CI) of each study were calculated and pooled.

RESULTS

No significant differences were observed in rates of total bleeding (RR = 0.91, 95% CI [0.57, 1.46], I(2) = 0.0%), thromboembolic complications (RR = 0.75, 95% CI [0.03, 18.22], I(2) = 0.0%), or total events (RR = 0.90, 95% CI [0.56, 1.44], I(2) = 0.0%) between apixaban and VKAs group. The frequency of major bleeding was similar between apixaban and VKAs group (RR = 1.34, 95% CI [0.34, 5.30], I(2) = 0.0%).

CONCLUSION

Apixaban was as effective and safe as VKAs in the periprocedural period of CA.

Use of intracardiac echocardiography during atrial fibrillation ablation to avoid complications

Antral pulmonary vein isolation is the cornerstone of current catheter ablation techniques. As technology and tools for performing the ablations have evolved and improved over the past decade, the safety and efficacy of the procedure have improved. The availability of preprocedure imaging, such as MRI and CT scan and intraprocedure imaging, especially intracardiac echocardiography, gives the operator the ability to have very accurate real-time representations of the cardiac anatomy with visualization of catheter positioning and for assessing for potential complications before they become clinically manifest. Much attention has been paid to decreasing the reliance on use of fluoroscopy and the safety of both the patient as well as the operator. This chapter reviews several aspects of the utility of intracardiac echocardiography imaging in minimizing complications during atrial fibrillation ablation.

Trends and predictors of readmission after catheter ablation for atrial fibrillation, 2009-2013

As the number of patients undergoing catheter ablation for atrial fibrillation (AF) increases, there is a growing focus on optimizing the quality and efficiency of. Readmission is often considered an indicator of both quality and efficiency of care delivery. We sought to estimate rates and identify predictors of readmission after catheter ablation.

METHODS AND RESULTS

Using a large, national administrative claims database, we identified all AF patients who underwent catheter ablation between January 2009 and December 2013 (10,705 ablation cases). We examined incident readmission and the primary diagnosis during the readmission episode of care. We used Cox proportional hazard models to identify associations between readmission and patient and institutional characteristics. A total of 1,433 (13.4%) ablation patients were readmitted within 90 days of ablation for any cause, and 573 (5.4%) were admitted with AF as the primary diagnosis. There was a decline in all-cause (from 15.6% to 12.8%; P = .04) and AF-related (6.4%-5.0 %; P = .03) 90-day readmission over the study period. In a multivariate model, earlier year of ablation and each of 9 chronic conditions (alone or in combination) were independently associated with risk of readmission.

CONCLUSIONS

Between 2009 and 2013, there was a reduction in 90-day readmission rates after AF ablation, suggesting improved periprocedural care of these patients. Identifying patients at high risk for readmission after catheter ablation for AF may offer an opportunity for early intervention and, ultimately, reduction in procedural morbidity and medical costs.

Surgical Treatment of Atrial Fibrillation

Atrial fibrillation (AF) is the most common chronic arrhythmia in the adult population. Ablation lines have largely replaced the historical and challenging cut and sew techniques. Surgical ablation of AF is commonly performed in cases with other indications for cardiac surgery and less commonly as a stand-alone therapy. Pulmonary vein isolation is the cornerstone of this procedure. Extended left atrial ablation lines may increase efficacy in cases with longstanding persistent or permanent AF. Additional efficacy by adding right atrial ablation is controversial but is often performed in cases undergoing right atrial or atrial septal surgery. Left atrial volume reduction is recommended in cases with large left atria and AF undergoing another cardiac surgery. Arrhythmia recurrence is not uncommon after surgical ablation of AF and varies among studies due to heterogeneity in patient population, lesion set and endpoints. Freedom from AF recurrence was 65-87% at 12 months and 58-70% at 2 years follow-up. Long-term monitoring is recommended due to an increased prevalence of asymptomatic recurrences. The strongest predictors of AF recurrence are longstanding or persistent AF and a large left atrium. The most common mechanisms of recurrence are pulmonary vein reconnection, nonpulmonary vein triggers, and gaps in the ablation lines. About 20% of atrial tachyarrhythmia recurrences are atrial flutter or atrial tachycardia. There are not enough data in the surgical literature to support withdrawal of anticoagulation after surgical AF ablation. Patients selected for stand-alone surgical ablation usually have low risk profiles and low postoperative mortality rates (0.2%).

Effect of Antiarrhythmic Drug Initiation on Readmission After Catheter Ablation for Atrial Fibrillation

OBJECTIVES

This study sought to evaluate the impact on antiarrhythmic drug (AAD) initiation on the risk of readmission after catheter ablation for atrial fibrillation (AF) among patients not already treated with an AAD.

BACKGROUND

Hospital readmission, a commonly tracked indicator of quality and efficiency of care delivery, occurs in about 15% patients within 90 days of undergoing catheter ablation for AF.

METHODS

Using a large national administrative claims database, we identified all atrial fibrillation patients (≥18 years of age) who underwent catheter ablation between January 2005 and December 2013 (n = 7,442). We identified the subset of patients who had not been on an AAD in the 90 days before ablation (n = 2,542) and, among those, the patients in whom an AAD was initiated at discharge following the ablation (n = 519).

RESULTS

The readmission rate was significantly lower among patients who were initiated on an AAD compared with those who were not (11.6% vs. 16.2%, p = 0.009). The association persisted after adjustment for age, sex, Charlson index, and CHADS₂ score (hazard ratio [HR]: 0.73, 95% confidence interval [CI]: 0.56 to 0.97; p = 0.03). In unadjusted time to event analysis, amiodarone (HR: 0.55, 95% CI: 0.32 to 0.94; p = 0.039) was associated with the greatest reduction in readmission whereas dronedarone, Class II agents, and Class IC agents had no statistically significant effect on readmission. AADs were discontinued in 44.5% of patients at 3 months.

CONCLUSIONS

Initiation of an AAD at discharge of catheter ablation is associated with a significant reduction in readmission within 90 days. Routine initiation of an AAD after catheter ablation may reduce healthcare utilization in the periablation period; however, the high rate of medication discontinuation may suggest that side effects or inefficacy may limit long-term AAD use post-ablation.

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.

Influence of Age and Gender on Complications of Catheter Ablation for Atrial Fibrillation

BACKGROUND

Despite catheter ablation (CA) has become an accepted treatment option for symptomatic, drug-resistant atrial fibrillation (AF), safety of this procedure continues to be cause for concern.

OBJECTIVE

Aim of the present multicenter study was to assess the influence of age and gender on incidence and severity of early CA complications.

METHODS

From January 1, 2011 to December 31, 2011, data from 2,323 consecutive patients who underwent CA (mean age 59.1+10.9; 72.3% male) for AF in 29 Italian centres were collected. All complications occurring to the patients from admission to 30th post-procedural day were recorded.

RESULTS

Complications occurred in 94 patients (4.0%); of these 7 (0.30%) developed permanent sequelae. There was a significant trend toward a greater incidence of complications with increasing age-group. In particular, the incidence of complications was 35/1066 (3.3%) in patients <60 year-old vs 59/1257 (4.7%) in those > 60 year-old (p=0.03). All 7 patients with permanent sequeale were older than 60. Females had a higher incidence of complications both among younger [13/231 (5.6%) vs 22/915 (2.5%), p=0.02] and older patients [32/405 (7.9%) vs 27/739 (3.5%) p=0.001]. In subjects older than 60, 5/405 (1.2%) females and 2/176 (0.3%) males (p=0.04) suffered from permanent sequelae.

CONCLUSIONS

Older patients and females are a subgroup at higher risk of complications during AF ablation. A particular care should be taken when performing CA in this clinical setting.

Catheter Ablation for Atrial Fibrillation: A Review of the Literature

Atrial fibrillation (AF) is the most frequent arrhythmia seen in clinical practice. The incidence of persistent and permanent AF will likely continue to increase as the population ages and as patients with structural heart disease live longer. Until recently, antiarrhythmic medications have been the only commonly employed treatment for maintaining sinus rhythm. However, antiarrhythmic medications have a modest long-term efficacy and the potential for serious side effects. Radiofrequency (RF) catheter ablation is now emerging as a viable alternative to antiarrhythmic medications in maintaining sinus rhythm in patients with AF. A number of different ablation strategies have been used including pulmonary vein isolation, targeting of fractionated electrograms, compartmentalising the atria with linear lesions and various combinations and modifications of these lesion sets. The variation in success within and between techniques suggests that the optimal ablation technique for AF is unclear. The general consensus for patients with paroxysmal atrial fibrillation is to achieve electrical isolation of the pulmonary veins (PVs). In patients with non-paroxysmal AF, PV isolation alone appears to be insufficient. In addition, the structural and electrophysiological changes that have typically occurred at the advanced stage of AF lend greater importance to the identification and ablation of atrial myocardial substrate-driven “sources”. Further efforts are needed to develop better techniques and tools to safely, effectively, and permanently isolate the pulmonary veins, to identify which sites are critical to the maintenance of AF, and to create durable lesions to interrupt intra-arterial reentry. In this review, the rationale and outcomes of rhythm management with drugs and ablation strategies targeting various mechanisms of AF based on our current understanding are discussed.

A contemporary review on the genetic basis of atrial fibrillation

Atrial fibrillation is the most common sustained cardiac arrhythmia, and affected individuals suffer from increased rates of heart failure, stroke, and death. Despite the enormous clinical burden that it exerts on patients and health care systems, contemporary treatment strategies have only modest efficacy that likely stems from our limited understanding of its underlying pathophysiology. Epidemiological studies have provided unequivocal evidence that the arrhythmia has a substantial heritable component. Subsequent investigations into the genetics underlying atrial fibrillation have suggested that there is considerable interindividual variability in the pathophysiology characterizing the arrhythmia. This heterogeneity may partly account for the poor treatment efficacy of current therapies. Subdividing atrial fibrillation into mechanistic subtypes on the basis of genotype illustrates the heterogeneous nature of the arrhythmia and may ultimately help guide treatment strategies. A pharmacogenetic approach to the management of atrial fibrillation may lead to dramatic improvements in treatment efficacy and improved patient outcomes.

Risk of stroke after catheter ablation versus cardioversion for atrial fibrillation: A propensity-matched study of 24,244 patients

BACKGROUND

Stroke is the major cause of morbidity and mortality related to atrial fibrillation (AF). Catheter ablation for AF is effective in reducing AF burden, but its impact on long-term stroke risk is unknown.

OBJECTIVE

We sought to evaluate the periprocedural and long-term stroke risk after catheter ablation or cardioversion for AF.

METHODS

This retrospective, propensity-matched study using a national administrative claims database identified patients with AF who underwent catheter ablation and a comparison group (matched on age, sex, year of treatment, CHA2DS2-Vasc score, and Charlson index) who underwent cardioversion between 2005 and 2012. The primary end points were (1) time to first ischemic or hemorrhagic stroke or transient ischemic attack (TIA) and (2) time to first ischemic or hemorrhagic stroke excluding TIA. We compared periprocedural incident stroke (within 30 days of ablation or cardioversion) as well as total strokes between the 2 groups.

RESULTS

A total of 24,244 patients (12,122 patients undergoing ablation and 12,122 patients undergoing cardioversion) were included in the analysis. Incident periprocedural stroke or TIA occurred in 0.5% of the ablation group and 0.3% of the cardioversion group (P = .04). There was a significant initial risk of stroke/TIA with ablation within the first 30 days (rate ratio 1.53; P = .05). After 30 days, this risk was significantly lower in the ablation group (rate ratio 0.78; P = .03).

CONCLUSION

In patients with AF, there is a small periprocedural stroke risk with ablation in comparison to cardioversion. However, over longer-term follow-up, ablation is associated with a slightly lower rate of stroke.

Catheter ablation for asymptomatic atrial fibrillation?

Ablation therapy for atrial fibrillation (AF) has been shown to be more efficient than medical treatment alone. Long-term success of AF ablation is still around 50% after one ablation and higher after two, with a substantial amount of asymptomatic recurrences in formerly symptomatic patients. Given the lack of evidence for superiority of rhythm control over rate control in terms of stroke reduction and mortality, AF ablation remains a treatment for symptom reduction only, although ablation has never been a part of these studies. There is early evidence that ablation could decrease the long-term risk of stroke; however, prospective studies are needed to assess whether this is the case and how patients with a successful ablation can be identified. If AF ablation can be shown to improve long-term morbidity, it could also become a reasonable treatment for patients with asymptomatic AF.