Catheter ablation of atrial fibrillation as first-line therapy--a single-centre experience

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.

Trends and predictors of early ablation for Atrial Fibrillation in a Nationwide population under age 65: a retrospective observational study

BACKGROUND

Catheter ablation (CA) has emerged as an effective treatment for symptomatic atrial fibrillation (AF). However practice patterns and patient factors associated with referral for CA within the first 12 months after diagnosis are poorly characterized. This study examined overall procedural trends and factors predictive of catheter ablation for newly-diagnosed atrial fibrillation in a young, commercially-insured population.

METHODS

A large nationally-representative sample of patients age 20 to 64 from years 2010 to 2016 was studied using the IBM MarketScan® Commercial Database. Patients were included with a new diagnosis of AF in the inpatient or outpatient setting with continuous enrollment for at least 1 year pre and post index visit. Patients were excluded if they had prior history of AF or had filled an anti-arrhythmic drug (AAD) in the pre-index period.

RESULTS

Early CA increased from 5.0% in 2010 to 10.5% in 2016. Patients were less likely to undergo CA if they were located in the Northeast (OR: 0.80, CI: 0.73-0.88) or North Central (OR: 0.91, CI: 0.83-0.99) regions (compared with the West), had higher CHA2DS2-VASc scores, or had Charlson Comorbidity Index (CCI) score of 3 or greater (OR: 0.61; CI: 0.51-0.72).

CONCLUSIONS

CA within 12 months for new-diagnosed AF increased significantly from 2010 to 2016, with most patients still trialed on an AAD prior to CA. Patients are less likely to be referred for early CA if they are located in the Northeast and North Central regions, have more comorbidities, or higher CHA2DS2-VASc scores.

Evaluation of the effect of prior antiarrhythmic drug use on the success of atrial fibrillation catheter ablation

WHAT IS KNOWN AND OBJECTIVE

Current guidelines recommend catheter ablation (CA) for atrial fibrillation (AF) refractory to at least one antiarrhythmic drug (AAD), but do not specify an adequate number of AADs to be trialed prior to considering ablation. The objective of this study was to evaluate the effect of CA success based on the number of AADs failed in patients with paroxysmal or persistent AF.

METHODS

This retrospective cohort study evaluated patients with paroxysmal or persistent AF who underwent an initial CA at a community hospital. Patients with unknown AAD histories, those who did not achieve acute procedural success, or who were lost to follow-up or death unrelated to thromboembolic stroke within 6 months post-ablation were excluded. Catheter ablation success was defined as freedom from AF. The primary outcome was the incidence of AF or atrial flutter captured on an electrocardiogram or other recording device at 3, 6, 9 and 12 months after the procedure.

RESULTS AND DISCUSSION

Overall, 99 out of 103 patients completed 1 year of follow-up. Of those patients, 34 of 99 (34.3%) experienced AF recurrence within 1-year post-ablation. There was no significant difference among the categories of number of failed AADs and the recurrence of AF within 12 months post-ablation for zero AADs, 1 AADs and ≥2 AADs (41.7%, 31.3% and 40%, respectively; P = 0.658).

WHAT IS NEW AND CONCLUSION

The results of this study do not support preferentially performing CA on patients who have failed a certain number of AADs. Results are limited by the nature of the study design and a small sample size. Conclusive results would best be addressed by a prospective randomized trial.

A randomized clinical trial of early invasive intervention for atrial fibrillation (EARLY-AF) - methods and rationale

BACKGROUND

The ideal management of patients with newly diagnosed symptomatic atrial fibrillation (AF) remains unknown. Current practice guidelines recommend a trial of antiarrhythmic drugs (AAD) prior to considering an invasive ablation procedure. However, earlier ablation offers an opportunity to halt the progressive patho-anatomical changes associated with AF, as well as impart other important clinical benefits.

OBJECTIVE

The aim of this study is to determine the optimal initial management strategy for patients with newly diagnosed, symptomatic atrial fibrillation.

METHODS/DESIGN

The EARLY-AF study (ClinicalTrials.govNCT02825979) is a prospective, open label, multicenter, randomized trial with a blinded assessment of outcomes. A total of 298 patients will be randomized in a 1:1 fashion to first-line AAD therapy, or first-line cryoballoon-based pulmonary vein isolation. Patients with symptomatic treatment naïve AF will be included. Arrhythmia outcomes will be assessed by implantable cardiac monitor (ICM). The primary outcome is time to first recurrence of AF, atrial flutter, or atrial tachycardia (AF/AFL/AT) between days 91 and 365 following AAD initiation or AF ablation. Secondary outcomes include arrhythmia burden, quality of life, and healthcare utilization.

DISCUSSION

The EARLY-AF study is a randomized trial designed to evaluate the optimal first management approach for patients with AF. We hypothesize that catheter ablation will be superior to drug therapy in prevention of AF recurrence.

Catheter Ablation as First-Line Therapy for Atrial Fibrillation: Ready for Prime-Time?

Current guidelines include atrial fibrillation (AF) catheter ablation as part of the management strategy in patients that have failed at least one oral antiarrhythmic drug treatment course. However, growing evidence derived from both randomized and non-randomized studies demonstrate lower rates of AF recurrence and AF burden in patients with paroxysmal AF that are naïve to antiarrhythmic drug treatment. Furthermore, progression from paroxysmal AF to persistent AF appears to be delayed by early catheter ablation of AF. The current review addresses the question of the best timing for ablation in patients with paroxysmal AF and provides the rationale for offering AF ablation as first-line therapy based on the most updated evidence available.

Ablation as First-Line Therapy for Atrial Fibrillation: Yes

This article addresses the use of catheter ablation (CA) as first-line therapy for atrial fibrillation (AF). CA increases long-term freedom from AF, reduces hospitalizations, and improves quality of life compared with antiarrhythmic drug (AAD) therapy in patients with symptomatic AF who have already failed one AAD. The role of CA as first-line therapy for AF, however, is still controversial. Evidence from randomized controlled trials shows that CA is definitely superior to AADs as first-line therapy for relatively young patients with paroxysmal AF, with comparable complication rates and results consistently reproducible across different institutions, operators, and types of ablation approaches.

Bridging the gender gap in atrial fibrillation

Women have a similar lifetime prevalence of non-valvular atrial fibrillation (NVAF) compared with that of men. Given the significant morbidity and potential mortality associated with NVAF, it is crucial to understand gender differences with NVAF. Women can be more symptomatic than men. Despite a higher baseline stroke risk, they are less likely to be on anticoagulation. Women have a greater risk of thromboembolism and a similar rate of bleeding risk compared with men on anticoagulation. Initial experience suggests that novel oral anticoagulants have similar safety and efficacy profile in men and women. Although women can have more adverse reactions from antiarrhythmic therapies, they are often referred later than men for ablation. As a group, a mitigating factor in ablation referral is that women also have a higher incidence of procedural complications from catheter ablation. This review summarizes the available literature highlighting significant gender-based differences and also highlights areas for research to improve NVAF outcomes in women.

Long-Term Follow-Up After Catheter Ablation of Paroxysmal Atrial Fibrillation

Background—

Although catheter ablation (CA) is a standard treatment for atrial fibrillation (AF), its long-term efficacy remains unclear. This study aimed to elucidate the incidences of AF recurrence and of progression from paroxysmal to persistent AF, after CA, in patients with paroxysmal AF.

Methods and Results—

We examined the incidence of AF recurrence and AF progression in 1220 consecutive patients (mean age, 61 years), with symptomatic paroxysmal AF, undergoing CA, based on extensive pulmonary vein isolation and focal ablation for nonpulmonary vein foci. AF recurrence–free survival probabilities at 5 years were 59.4% after the initial CA and 81.1% after the final CA (average, 1.3 procedures). During a median follow-up period of 47.9 (range, 5.3–123.3) months after the initial CA, AF progressed from paroxysmal to persistent in 15 (1.2%) patients (0.3%/y). The duration of AF history (hazard ratio [HR], 1.03; P <0.0001), number of ineffective antiarrhythmics (HR, 1.09; P =0.005), and left atrial diameter indexed by the body surface area (HR, 1.05; P =0.001) were significant predictors of AF recurrence. Patient age (HR, 1.12; P =0.0001) and left atrial diameter indexed by the body surface area (HR, 1.26; P =0.0006) were significantly associated with AF progression. Patients aged ≤65 years and with a left atrial diameter indexed by the body surface area of ≤24.0 mm/m 2 did not develop AF progression for ≤10 years after the initial CA.

Conclusions—

Although the long-term follow-up revealed the effect of CA on preventing AF recurrence, repeated CA sessions might be required. The rate of progression from paroxysmal to persistent AF was 0.3%/y.

Immediate and medium-term outcomes of cryoballoon-based pulmonary vein isolation in patients with paroxysmal and persistent atrial fibrillation: single-centre experience

BACKGROUND

Pulmonary vein (PV) isolation with cryoballoon is a recently developed technique for the treatment of atrial fibrillation (AF) with acceptable mid-term results in terms of the success and safety. The purpose of our study is to identify the periprocedural complications, mid-term success rates and predictors of recurrence after AF ablation with cryoballoon.

METHOD

A total of 236 patients (54% male, mean age 54.6 ± 10.45 years and 79.6% paroxysmal AF) with symptomatic AF underwent PV isolation with cryoballoon due to failure with ≥1 antiarrhythmic drug previously. Procedural success, complications and follow-up data were defined according to recent guidelines.

RESULTS

Acute procedural success rate was 99.5%. Mean procedural and fluoroscopy times were 72.5 ± 5.3 and 14 ± 3.5 min. At a median of 18 (6-27) months follow-up, 80.8% of paroxysmal AF patients and 50.0% of persistent AF patients were free from AF recurrence. In multivariate regression analysis, body mass index (BMI) (hazard ratio (HR), 1.35; 95% confidence interval (CI), 1.18-2.93, p = 0.001), smoking (HR, 2.12; 95% CI, 1.36-6.67, p < 0.001), non-paroxysmal AF (HR, 1.26; 95% CI, 1.12-2.56, p = 0.024), duration of AF (HR, 1.42; 95% CI, 1.18-2.61, p = 0.015), left atrium (LA) diameter (HR, 2.42; 95% CI, 1.64-5.88, p < 0.001) and early AF recurrence (HR, 4.88; 95% CI, 2.86-35.6, p < 0.001) were independent predictors of AF recurrence following cryoablation.

CONCLUSION

Our results showed that AF ablation with cryoballoon is effective and safe. Non-paroxysmal AF, duration of AF, smoking, BMI, LA diameter and early recurrence were found to be the most powerful predictors and could be helpful to select patients for appropriate therapeutic strategy.

The impact of haemodialysis on the outcomes of catheter ablation in patients with paroxysmal atrial fibrillation

AIMS

The outcomes of catheter ablation (CA) in patients with paroxysmal atrial fibrillation (PAF) who are undergoing haemodialysis (HD) have not been fully elucidated. This study aimed to determine the impact of HD on CA outcome in these patients.

METHODS AND RESULTS

We examined 1364 consecutive PAF patients (mean age, 61 ± 10 years) who underwent CA, including 32 (2.3%) patients undergoing HD. The patients undergoing HD had a significantly lower body mass index (P < 0.0001), higher CHADS2 score (P = 0.006), and higher prevalence of structural heart disease (P < 0.0001), hypertension (P = 0.002), and congestive heart failure (P = 0.02). Echocardiography indicated a larger left atrial diameter (P < 0.0001) and left ventricular diameter (P = 0.0002) in the HD patients. Haemodialysis was a significant predictor of AF recurrence (hazard ratio 2.56; 95% confidence interval 1.56-4.03; P = 0.0004) in the overall population. Sinus rhythm maintenance rates in the HD patients at 1, 3, and 5 years were 42.3, 37.6, and 19.7%, respectively, after the first procedure, and 64.7, 54.9, and 47.1%, respectively, after the final procedure (median, 2; range, 1-2 procedures); these rates were significantly lower than those in the non-HD patients (P < 0.0001). The 5-year survival rate was 78.1% in the HD patients.

CONCLUSION

Haemodialysis was significantly associated with AF recurrence after CA for PAF. However, an ∼50% success rate for sinus rhythm maintenance without antiarrhythmic drug therapy in HD patients suggested that CA could be an option for the treatment of AF.

Radiofrequency ablation as initial therapy in paroxysmal atrial fibrillation

BACKGROUND

There are limited data comparing radiofrequency catheter ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation.

METHODS

We randomly assigned 294 patients with paroxysmal atrial fibrillation and no history of antiarrhythmic drug use to an initial treatment strategy of either radiofrequency catheter ablation (146 patients) or therapy with class IC or class III antiarrhythmic agents (148 patients). Follow-up included 7-day Holter-monitor recording at 3, 6, 12, 18, and 24 months. Primary end points were the cumulative and per-visit burden of atrial fibrillation (i.e., percentage of time in atrial fibrillation on Holter-monitor recordings). Analyses were performed on an intention-to-treat basis.

RESULTS

There was no significant difference between the ablation and drug-therapy groups in the cumulative burden of atrial fibrillation (90th percentile of arrhythmia burden, 13% and 19%, respectively; P=0.10) or the burden at 3, 6, 12, or 18 months. At 24 months, the burden of atrial fibrillation was significantly lower in the ablation group than in the drug-therapy group (90th percentile, 9% vs. 18%; P=0.007), and more patients in the ablation group were free from any atrial fibrillation (85% vs. 71%, P=0.004) and from symptomatic atrial fibrillation (93% vs. 84%, P=0.01). One death in the ablation group was due to a procedure-related stroke; there were three cases of cardiac tamponade in the ablation group. In the drug-therapy group, 54 patients (36%) underwent supplementary ablation.

CONCLUSIONS

In comparing radiofrequency ablation with antiarrhythmic drug therapy as first-line treatment in patients with paroxysmal atrial fibrillation, we found no significant difference between the treatment groups in the cumulative burden of atrial fibrillation over a period of 2 years. (Funded by the Danish Heart Foundation and others; MANTRA-PAF ClinicalTrials.gov number, NCT00133211.).

Outcome of Patients Discharged after their First Detected Episode of Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent supraventricular arrhythmia with an approximative prevalence of 1 % in the general population and above 6 % in the elderly. After a first AF diagnosis, the hospitalization rate is markedly increased. Management of a first AF episode is different depending on the clinical status of patients. Practical guidelines developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society are available for the management of these patients. A four-step decisional scheme must be followed in the management of a first recent AF episode: need for a short- and long-term anticoagulation, define a rythmologic strategy (rhythm or rate control), select the weapon (drug, device or ablation) and reconsider the strategy if needed. After a first uncomplicated paroxysmal AF episode, guidelines recommend that prescription of antiarrhythmics must be avoided and anticoagulation is optional. After a first persistent AF episode, guidelines recommend to either respect or reduce the arrhythmia. Prescription of antiarrhythmics and anticoagulation is also optional depending on the patient?s condition. In case of the AF reduction decision, anticoagulation must be tailored preliminary to this reduction. AF recurrence rate varies depending on the patient?s condition, and the risk of stroke assessed by the CHA₂DS₂-VASc score might be similarly considered for both paroxysmal and persistent AF.

Prior antiarrhythmic drug use and the outcome of atrial fibrillation ablation

Aims

Atrial fibrillation (AF) ablation is generally performed after patients fail antiarrhythmic drug (AAD) therapy. Some patients have drug contraindications or choose to avoid a lifetime of drug therapy. Little is known about the impact of previous drug therapy on ablation outcomes. We evaluated AAD use before AF ablation and its impact on ablation outcomes.

Methods and results

We evaluated freedom from AF after ablation and patients' clinical characteristics by number of AADs failed in 1125 patients undergoing 1504 ablations. We also evaluated reasons why some patients did not receive prior drug therapy. Cox multivariate analysis examined factors predicting ablation failure. Patients failing more drugs before ablation were older (P = 0.001), had a longer duration of AF (P = 0.0001), were more likely female (P = 0.037), had more repeat ablations (P = 0.045), and less paroxysmal AF (P = 0.003). For patients with either paroxysmal or persistent AF, the number of drugs failed predicted AF recurrence (P = 0.0001). Other factors predicting AF recurrence following final ablation included age (P = 0.004), left atrial size (P = 0.002), female gender (P = 0.0001), and persistent AF (P = 0.0001). The reason for not receiving prior drug therapy was medical in 21.5% and patient choice in 78.5%. Number of drugs failed did not influence ablation outcome for patients with long-standing persistent AF (P = 0.352).

Conclusions

For paroxysmal and persistent AF patients undergoing ablation, those failing fewer AADs have different clinical characteristics than those who fail more drugs. Our study also suggests that the more drugs failed pre-ablation, the lower the freedom from AF post-procedure, possibly due to AF progression during drug trials.