Current Evidence and Recommendations for Rate Control in Atrial Fibrillation.
ABSTRACT: Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice, which is associated with substantial risk of stroke and thromboembolism. As an arrhythmia that is particularly common in the elderly, it is an important contributor towards morbidity and mortality. Ventricular rate control has been a preferred and therapeutically convenient treatment strategy for the management of AF. Recent research in the field of rhythm control has led to the advent of newer antiarrhythmic drugs and catheter ablation techniques as newer therapeutic options. Currently available antiarrhythmic drugs still remain limited by their suboptimal efficacy and significant adverse effects. Catheter ablation as a newer modality to achieve sinus rhythm (SR) continues to evolve, but data on long-term outcomes on its efficacy and mortality outcomes are not yet available. Despite these current developments, rate control continues to be the front-line treatment strategy, especially in older and minimally symptomatic patients who might not tolerate the antiarrhythmic drug treatment. This review article discusses the current evidence and recommendations for ventricular rate control in the management of AF. We also highlight the considerations for rhythm control strategy in the management of patients of AF.
Project description:In patients with longstanding persistent atrial fibrillation (AF), outcomes from catheter ablation remain suboptimal. The convergent procedure combines minimally invasive surgical ablation with subsequent catheter ablation, and may contribute towards maintenance of sinus rhythm in this patient group. We performed the convergent procedure on 43 patients with longstanding persistent AF from 2013-2018. Patients underwent clinical review at 3, 6, and 12 months and thereafter as necessitated by their symptoms. Our dataset describes patients' baseline characteristics and rhythm control protocols, as well as outcomes including arrhythmia recurrence, the need for antiarrhythmic drugs, requirement for repeat rhythm control procedures, and complications. These data provide a real world insight into the risks and benefits of the convergent procedure in patients with longstanding persistent AF.
Project description:The management of non-paroxysmal atrial fibrillation (AF) remains controversial. We examined the efficacy and safety of the 2 stage Hybrid AF ablation approach by analysing the largest series of this technique reported so far. Methods:The approach aims to electrically isolate the left atrial posterior wall incorporating the pulmonary veins ('box-set'pattern). An initial video-assisted thoracoscopic (VATS) epicardial ablation is followed after a minimum of 8 weeks by endocardial radiofrequency catheter ablation. Results:Of 175 patients from 4 European cardiothoracic centers, who underwent the surgical (COBRA Fusion, AtriCure Inc) 1st stage ablation, 166 went on to complete 2nd stage catheter ablation. At median follow up of 18 months post 2nd stage procedure 93/166 (56%) had remained free of AF or atrial tachycardia (AT) recurrence off antiarrhythmic drugs. 110/175 62.9% were in sinus rhythm off all antiarrhythmic drugs at last clinic follow-up (132/175 75.4% including those on antiarrhythmic drugs). 18 patients (10.8%) underwent a further re-do ablation (mean of 1.1 ablations per patient) 105/166 (63%) remained free of AF/AT recurrence off antiarrhythmic drugs following last ablation procedure.Latterly, ILRs have been implanted in patients (n = 56); 60% have remained fully arrhythmia free and 80% have shown AF burden < 5% at a median 14 months follow-up [IQR: 13.5 (8-21.5)]. Only 10.9% have reverted to persistent AF. 5 patients (2.9%) had a perioperative stroke and 4 patients (2.3%) exhibited persistent weakness of the right hemidiaphragm following stage 1 VATS epicardial ablation. One patient died following stroke (overall mortality 0.6%). Conclusions:In patients with non-paroxysmal AF with unfavourable characteristics for catheter ablation, the staged hybrid approach results in acceptable levels of freedom from recurrent atrial arrhythmia, however, complication rates are higher than with catheter ablation alone.
Project description:Although pharmacological rhythm control of AF in patients with heart failure with reduced ejection fraction (HFrEF) does not seem to provide any benefit over rate control, catheter ablation of AF has been shown to improve clinical outcomes. These results can be explained with higher success rates of catheter ablation in restoring and maintaining sinus rhythm compared with antiarrhythmic drugs. In addition, pharmacotherapy is not void of side-effects, which are thought to offset its potential antiarrhythmic benefits. Therefore, efforts should be made towards optimisation of ablation techniques for AF in patients with HFrEF.
Project description:OPINION STATEMENT:Atrial fibrillation (AF) remains a major risk factor for stroke. Unfortunately, clinical trials have failed to demonstrate that a strategy of rhythm control--therapy to maintain normal sinus rhythm (NSR)--reduces stroke risk. The apparent lack of benefit of rhythm control likely reflects the difficulty in maintaining NSR using currently available therapies. However, there are signals from several trials that the presence of NSR is indeed beneficial and associated with better outcomes related to stroke and mortality. Most electrophysiologists feel that as rhythm control strategies continue to improve, the crucial link between rhythm control and stroke reduction will finally be demonstrated. Therefore, AF specialists tend to be aggressive in their attempts to maintain NSR, especially in patients who have symptomatic AF. A step-wise approach from antiarrhythmic drugs to catheter ablation to cardiac surgery is generally used. In select patients, catheter ablation or cardiac surgery may supersede antiarrhythmic drugs. The choice depends on the type of AF, concurrent heart disease, drug toxicity profiles, procedural risks, and patient preferences. Regardless of strategy, given the limited effectiveness of currently available rhythm control therapies, oral anticoagulation is still recommended for stroke prophylaxis in AF patients with other stroke risk factors. Major challenges in atrial fibrillation management include selecting patients most likely to benefit from rhythm control, choosing specific antiarrhythmic drugs or procedures to achieve rhythm control, long-term monitoring to gauge the efficacy of rhythm control, and determining which (if any) patients may safely discontinue anticoagulation if long-term NSR is achieved.
Project description:Atrial fibrillation (AF) is an age-related arrhythmia of enormous socioeconomic significance. In recent years, our understanding of the basic mechanisms that initiate and perpetuate AF has evolved rapidly, catheter ablation of AF has progressed from concept to reality, and recent studies suggest lifestyle modification may help prevent AF recurrence. Emerging developments in genetics, imaging, and informatics also present new opportunities for personalized care. However, considerable challenges remain. These include a paucity of studies examining AF prevention, modest efficacy of existing antiarrhythmic therapies, diverse ablation technologies and practice, and limited evidence to guide management of high-risk patients with multiple comorbidities. Studies examining the long-term effects of AF catheter ablation on morbidity and mortality outcomes are not yet completed. In many ways, further progress in the field is heavily contingent on the feasibility, capacity, and efficiency of clinical trials to incorporate the rapidly evolving knowledge base and to provide substantive evidence for novel AF therapeutic strategies. This review outlines the current state of AF prevention and treatment trials, including the foreseeable challenges, as discussed by a unique forum of clinical trialists, scientists, and regulatory representatives in a session endorsed by the Heart Rhythm Society at the 12th Global CardioVascular Clinical Trialists Forum in Washington, DC, December 3-5, 2015.
Project description:<h4>Importance</h4>In patients with paroxysmal atrial fibrillation (AF), rhythm control with either antiarrhythmic drugs (AADs) or catheter ablation has been associated with decreased symptoms, prevention of adverse remodeling, and improved cardiovascular outcomes. Adoption of advanced cardiovascular therapeutics, however, is often slower among patients from racial/ethnic minority groups and those with lower income.<h4>Objective</h4>To ascertain the cumulative rates of AAD and catheter ablation use for the management of paroxysmal AF and to investigate for the presence of inequities in AF management by evaluating the association of race/ethnicity and socioeconomic status with their use in the United States.<h4>Design, setting, and participants</h4>This cohort study obtained inpatient, outpatient, and pharmacy claims data from the Optum Clinformatics Data Mart between October 1, 2015, and June 30, 2019. Adult patients (aged ?18 years) in the database with a diagnosis of incident paroxysmal AF were identified. Patients were excluded if they did not have continuous insurance enrollment for at least 1 year before and at least 6 months after study entry.<h4>Exposures</h4>Race/ethnicity and zip code-linked median household income.<h4>Main outcomes and measures</h4>Treatment with a rhythm control strategy, and catheter ablation specifically, among those who received rhythm control. Multivariable logistic regression models were used to assess the association of race/ethnicity and zip code-linked median household income with a rhythm control strategy (AADs or catheter ablation) vs a rate control strategy as well as with catheter ablation vs AADs among those receiving rhythm control.<h4>Results</h4>Of the 109?221 patients who met the inclusion criteria, 55 185 were men (50.5%) and 73 523 were White (67.3%), with a median (interquartile range) age of 75 (68-82) years. A total of 86?359 patients (79.1%) were treated with rate control, 19?362 patients (17.7%) with AADs, and 3500 (3.2%) with catheter ablation. Between 2016 and 2019, the cumulative percentage of patients treated with catheter ablation increased from 1.6% to 3.8%. In multivariable analyses, Black race (adjusted odds ratio [aOR], 0.89; 95% CI, 0.83-0.94; P < .001) and lower zip code-linked median household income (aOR for <$50?000: 0.83 [95% CI, 0.79-0.87; P?<?.001]; aOR for $50 000-$99 999: 0.92 [95% CI, 0.88-0.96; P?=?<.001] compared with ?$100?000) were independently associated with lower use of rhythm control. Latinx ethnicity (aOR, 0.73; 95% CI, 0.60-0.89; P?=?.002) and lower zip code-linked median household income (aOR for <$50?000: 0.61 [95% CI, 0.54-0.69; P?<?.001]; aOR for $50 000-$99 999: 0.81 [95% CI, 0.72-0.90; P?<?.001] compared with ?$100?000) were independently associated with lower catheter ablation use among those receiving rhythm control.<h4>Conclusions and relevance</h4>This study found that despite increased use of rhythm control strategies for treatment of paroxysmal AF, catheter ablation use remained low and patients from racial/ethnic minority groups and those with lower income were less likely to receive rhythm control treatment, especially catheter ablation. These findings highlight inequities in paroxysmal AF management based on race/ethnicity and socioeconomic status.
Project description:The use of catheter ablation to treat AF is increasing rapidly, but there is presently an incomplete understanding of its cost-effectiveness. AF ablation procedures involve significant up-front expenditures, but multiple randomized trials have demonstrated that ablation is more effective than antiarrhythmic drugs at maintaining sinus rhythm in a second-line and possibly first-line rhythm control setting. Although truly long-term data are limited, ablation, as compared with antiarrrhythmic drugs, also appears associated with improved symptoms and quality of life and a reduction in downstream hospitalization and other health care resource utilization. Several groups have developed cost effectiveness models comparing AF ablation primarily to antiarrhythmic drugs and the model results suggest that ablation likely falls within the range generally accepted as cost-effective in developed nations. This paper will review available information on the cost-effectiveness of catheter ablation for the treatment of atrial fibrillation, and discuss continued areas of uncertainty where further research is required.
Project description:BACKGROUND:Catheter ablation of atrial fibrillation (AF) is an established second line therapy for patients with symptomatic paroxysmal AF (PAF) and may be considered as a first line therapy in selected patients who are highly symptomatic, considering patient choice, benefit, and risk, according to recent guidelines. Our study investigated whether a first line vs. second line ablation approach may result in improved sinus rhythm maintenance after ablation. METHODS:A total of 153 patients undergoing pulmonary vein isolation for PAF were included in the study (age 55±12 years, 29% female). Seventy-nine patients underwent first line AF ablation and 74 patients underwent second line AF ablation after failed antiarrhythmic drug therapy. There was no significant difference in baseline characteristics such as age, history of AF, left atrial size or LVEF between groups. Success was defined as atrial tachyarrhythmia free survival during a 12-month follow-up by means of serial ECG Holter monitoring. RESULTS:There was no significant difference in cumulative arrhythmia-free survival between those patients who received AF ablation as a first or second line therapy. Single procedure success was 78% in the first line group vs. 81% in the second line group; multiple procedure success was 90 vs. 91%, (n.s.). Complication rate was 1.3% vs. 1.4% (n.s.). CONCLUSION:Success of AF ablation did not differ between patients who receive ablation as first vs. second line therapy. Based on these data, a trial of AAD therapy before AF ablation may be justified in most patients with symptomatic PAF eligible for rhythm control.
Project description:The efficacy and safety of catheter ablation for the management of atrial fibrillation (AF) has been improved in recent years. Radiofrequency (RF) catheter ablation for maintaining sinus rhythm is superior to the current antiarrhythmic drug therapy in selected patients. Pulmonary vein isolation (PVI) is the cornerstone of various catheter ablation strategies. It is well recognized that pulmonary vein (PV) antrum contributes to the AF initiation and/or perpetuation. Since PV stenosis is a complication of ablation within a PV, the ablation site for PVI has shifted to the junction between the left atrium and the PV rather than the ostium of the PV. However, PV reconnection after ablation is the major cause of recurrence of AF. The recovery of PV conduction could be caused by anatomical variations such as the failure to produce complete transmural lesion or gaps at the ablation line due to the transient electrophysiologic effects from the RF ablation. In this review, we discussed several factors to be considered for the achievement of the best PVI, including clinical aspects and technical aspects.
Project description:Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide requiring therapy. Despite recent advances in catheter-based and surgical therapy, antiarrhythmic drugs (AADs) remain the mainstay of treatment for symptomatic AF. However, response in individual patients is highly variable with over half the patients treated with rhythm control therapy experiencing recurrence of AF within a year. Contemporary AADs used to suppress AF are incompletely and unpredictably effective and associated with significant risks of proarrhythmia and noncardiac toxicities. Furthermore, this "one-size" fits all strategy for selecting antiarrhythmics is based largely on minimizing risk of adverse effects rather than on the likelihood of suppressing AF. The limited success of rhythm control therapy is in part due to heterogeneity of the underlying substrate, interindividual differences in disease mechanisms, and our inability to predict response to AADs in individual patients. Genetic studies of AF over the past decade have revealed that susceptibility to and response to therapy for AF is modulated by the underlying genetic substrate. However, the bedside application of these new discoveries to the management of AF patients has thus far been disappointing. This may in part be related to our limited understanding about genetic predictors of drug response in general, the challenges associated with determining efficacy of response to AADs, and lack of randomized genotype-directed clinical trials. Nonetheless, recent studies have shown that common AF susceptibility risk alleles at the chromosome 4q25 locus modulated response to AADs, electrical cardioversion, and ablation therapy. This monograph discusses how genetic approaches to AF have not only provided important insights into underlying mechanisms but also identified AF subtypes that can be better targeted with more mechanism-based "personalized" therapy.