Modifiable Risk Factors and Atrial Fibrillation Lau, Dennis H; Nattel, Stanley; Kalman, Jonathan M ...
Circulation (New York, N.Y.),
2017-Aug-08, 2017-08-08, 20170808, Letnik:
136, Številka:
6
Journal Article
Recenzirano
Odprti dostop
There has been increasing focus on the rising burden of atrial fibrillation (AF) since the turn of the millennium. The AF epidemic is projected not only to have an impact on morbidity and mortality, ...but also to result in increasing healthcare use and cost. Intensive research over the previous decades has improved our understanding of this complex arrhythmia while unraveling more knowledge gaps and inadequacies of current therapeutic options. Specifically, the advances in catheter ablation technology and strategies have not translated into significant gains in procedural success rates over recent years. Therefore, strategies aiming at lowering the risk of AF development and progression are urgently needed to curtail the AF epidemic and improve outcomes in affected individuals. Recent research has highlighted the potential beneficial effects of lifestyle and risk factor management for AF as upstream noninvasive therapy. The evidence supporting this treatment paradigm beyond routine clinical AF management argues for change in the delivery of care to patients who have this debilitating arrhythmia. In this review, we highlight the contributory role of risk factors to AF pathogenesis from both bench and bedside studies. Next, we discuss the rationale and potential benefits of risk factor modification for sinus rhythm maintenance. Last, we propose an integrated care model to incorporate risk factor modification as the fourth pillar of AF care in conjunction with established pillars of rate control, rhythm control, and anticoagulation therapy.
Abstract Background Obesity and atrial fibrillation (AF) are public health issues with significant consequences. Objectives This study sought to delineate the development of global ...electrophysiological and structural substrate for AF in sustained obesity. Methods Ten sheep fed ad libitum calorie-dense diet to induce obesity over 36 weeks were maintained in this state for another 36 weeks; 10 lean sheep with carefully controlled weight served as controls. All sheep underwent electrophysiological and electroanatomic mapping; hemodynamic and imaging assessment (echocardiography and dual-energy x-ray absorptiometry); and histology and molecular evaluation. Evaluation included atrial voltage, conduction velocity (CV), and refractoriness (7 sites, 2 cycle lengths), vulnerability for AF, fatty infiltration, atrial fibrosis, and atrial transforming growth factor (TGF)-β1 expression. Results Compared with age-matched controls, chronically obese sheep demonstrated greater total body fat (p < 0.001); LA volume (p < 0.001); LA pressure (p < 0.001), and PA pressures (p < 0.001); reduced atrial CV (LA p < 0.001) with increased conduction heterogeneity (p < 0.001); increased fractionated electrograms (p < 0.001); decreased posterior LA voltage (p < 0.001) and increased voltage heterogeneity (p < 0.001); no change in the effective refractory period (ERP) (p > 0.8) or ERP heterogeneity (p > 0.3). Obesity was associated with more episodes (p = 0.02), prolongation (p = 0.01), and greater cumulative duration (p = 0.02) of AF. Epicardial fat infiltrated the posterior LA in the obese group (p < 0.001), consistent with reduced endocardial voltage in this region. Atrial fibrosis (p = 0.03) and TGF-β1 protein (p = 0.002) were increased in the obese group. Conclusions Sustained obesity results in global biatrial endocardial remodeling characterized by LA enlargement, conduction abnormalities, fractionated electrograms, increased profibrotic TGF-β1 expression, interstitial atrial fibrosis, and increased propensity for AF. Obesity was associated with reduced posterior LA endocardial voltage and infiltration of contiguous posterior LA muscle by epicardial fat, representing a unique substrate for AF.
Catheter ablation is at the forefront of the management of a range of atrial arrhythmias. In this Series paper, we discuss the underlying mechanisms and the current role of catheter ablation for the ...three most common atrial arrhythmias encountered in clinical practice: focal atrial tachycardia, atrial flutter, and atrial fibrillation. The mechanisms of focal atrial tachycardia and atrial flutter are well understood, and these arrhythmias are amenable to curative catheter ablation with high success rates. In most cases, paroxysmal atrial fibrillation is initiated by triggers located within pulmonary vein musculature. Circumferential ablation to isolate this musculature is associated with high success rates for elimination of paroxysmal atrial fibrillation in selected populations. Because of the problem of recurrent pulmonary vein connection, more than one procedure will be needed in about 30% of patients, and new technologies are being developed to reduce this occurrence. The mechanisms that sustain persistent atrial fibrillation are not well understood and are the subject of continuing investigation. As such, ablation approaches and technologies for this arrhythmia are still evolving.
The role of obesity in atrial fibrillation Nalliah, Chrishan Joseph; Sanders, Prashanthan; Kottkamp, Hans ...
European heart journal,
2016-May-21, 2016-05-21, 20160521, Letnik:
37, Številka:
20
Journal Article
Recenzirano
Odprti dostop
Atrial fibrillation (AF) is commonly associated with overweight and obesity. Both conditions have been identified as major global epidemics associated with increased mortality and morbidity. ...Overweight populations have higher incidence, prevalence, severity, and progression of AF compared with their normal weight counterparts. Additionally, weight change appears to accompany alteration of arrhythmia profile, raising overweight, and obesity as potential targets for intervention. Recent clinical data confirm hypothesis drawn from epidemiological studies that durable weight reduction strategies facilitate effective management of AF. Stable weight loss decreases AF burden and AF recurrence following treatment. Structural remodelling in response to weight loss suggests that reverse remodelling of the AF substrate mediates improvement of arrhythmia profile. Obesity often co-exists with multiple AF risk factors that improve in response to weight loss, making a consolidated approach of weight loss and AF risk factor management preferable. However, weight loss for AF remains in its infancy, and its broad adoption as a management strategy for AF remains to be defined.
Abstract Background The long-term outcome of atrial fibrillation (AF) ablation demonstrates attrition. This outcome may be due to failure to attenuate the progressive substrate promoted by ...cardiovascular risk factors. Objectives The goal of this study was to evaluate the impact of risk factor and weight management on AF ablation outcomes. Methods Of 281 consecutive patients undergoing AF ablation, 149 with a body mass index ≥27 kg/m2 and ≥1 cardiac risk factor were offered risk factor management (RFM) according to American Heart Association/American College of Cardiology guidelines. After AF ablation, all 61 patients who opted for RFM and 88 control subjects were assessed every 3 to 6 months by clinic review and 7-day Holter monitoring. Changes in the Atrial Fibrillation Severity Scale scores were determined. Results There were no differences in baseline characteristics, number of procedures, or follow-up duration between the groups (p = NS). RFM resulted in greater reductions in weight (p = 0.002) and blood pressure (p = 0.006), and better glycemic control (p = 0.001) and lipid profiles (p = 0.01). At follow-up, AF frequency, duration, symptoms, and symptom severity decreased more in the RFM group compared with the control group (all p < 0.001). Single-procedure drug-unassisted arrhythmia-free survival was greater in RFM patients compared with control subjects (p < 0.001). Multiple-procedure arrhythmia-free survival was markedly better in RFM patients compared with control subjects (p < 0.001), with 16% and 42.4%, respectively, using antiarrhythmic drugs (p = 0.004). On multivariate analysis, type of AF (p < 0.001) and RFM (hazard ratio 4.8 95% confidence interval: 2.04 to 11.4; p < 0.001) were independent predictors of arrhythmia-free survival. Conclusions Aggressive RFM improved the long-term success of AF ablation. This study underscores the importance of therapy directed at the primary promoters of the AF substrate to facilitate rhythm control strategies.
Abstract
Aims
To determine stroke risk in subclinical atrial fibrillation (AF) and temporal association between subclinical AF and stroke.
Methods and results
Pubmed/Embase was searched for studies ...reporting stroke in subclinical AF in patients with cardiac implantable electronic devices (CIEDs). After exclusions, 11 studies were analysed. Of these seven studies reported prevalence of subclinical AF, two studies reported association between subclinical and clinical AF, seven studies reported stroke risk in subclinical AF, and five studies reported temporal relationship between subclinical AF and stroke. Subclinical AF was noted after CIEDs implant in 35% interquartile range (IQR) 34–42 of unselected patients with pacing indication over 1–2.5 years. The definition and cut-off duration (for stroke risk) of subclinical AF varied across studies. Subclinical AF was strongly associated with clinical AF (OR 5.7, 95% CI 4.0–8.0, P < 0.001, I2 = 0%). The annual stroke rate in patients with subclinical AF > defined cut-off duration was 1.89/100 person-year (95% CI 1.02–3.52) with 2.4-fold (95% CI 1.8–3.3, P < 0.001, I2 = 0%) increased risk of stroke as compared to patients with subclinical AF < cut-off duration (absolute risk was 0.93/100 person-year). Three studies provided mean CHADS2 score. In these studies, with mean CHADS2 score of 2.1 ± 0.1, subclinical AF was associated with annual stroke rate of 2.76/100 person-years (95% CI 1.46–5.23). After excluding patients without AF, only 17% strokes occurred in presence of ongoing AF. Subclinical AF was noted in 29% IQR 8–57 within 30 days preceding stroke.
Conclusion
Subclinical AF strongly predicts clinical AF and is associated with elevated absolute stroke risk albeit lower than risk described for clinical AF.
Atrial fibrillation (AF) is a progressive disease. Obesity is associated with progression of AF. This study evaluates the impact of weight and risk factor management (RFM) on progression of the AF.
...As described in the Long-Term Effect of Goal-Directed Weight Management in an Atrial Fibrillation Cohort: A Long-Term Follow-Up (LEGACY) Study, of 1415 consecutive AF patients, 825 had body mass index ≥ 27 kg/m2 and were offered weight and RFM. After exclusion, 355 were included for analysis. Weight loss was categorized as: Group 1 (<3%), Group 2 (3-9%), and Group 3 (≥10%). Change in AF type was determined by clinical review and 7-day Holter yearly. Atrial fibrillation type was categorized as per the Heart Rhythm Society consensus. There were no differences in baseline characteristic or follow-up duration between groups (P = NS). In Group 1, 41% progressed from paroxysmal to persistent and 26% from persistent to paroxysmal or no AF. In Group 2, 32% progressed from paroxysmal to persistent and 49% reversed from persistent to paroxysmal or no AF. In Group 3, 3% progressed to persistent and 88% reversed from persistent to paroxysmal or no AF (P < 0.001). Increased weight loss was significantly associated with greater AF freedom: 45 (39%) in Group 1, 69 (67%) in Group 2, and 116 (86%) in Group 3 (P ≤ 0.001).
Obesity is associated with progression of the AF disease. This study demonstrates the dynamic relationship between weight/risk factors and AF. Weight-loss management and RFM reverses the type and natural progression of AF.
Alcohol and Atrial Fibrillation: A Sobering Review Voskoboinik, Aleksandr; Prabhu, Sandeep; Ling, Liang-Han ...
Journal of the American College of Cardiology,
12/2016, Letnik:
68, Številka:
23
Journal Article
Recenzirano
Odprti dostop
Alcohol is popular in Western culture, supported by a perception that modest intake is cardioprotective. However, excessive drinking has detrimental implications for cardiovascular disease. Atrial ...fibrillation (AF) following an alcohol binge or the "holiday heart syndrome" is well characterized. However, more modest levels of alcohol intake on a regular basis may also increase the risk of AF. The pathophysiological mechanisms responsible for the relationship between alcohol and AF may include direct toxicity and alcohol's contribution to obesity, sleep-disordered breathing, and hypertension. We aim to provide a comprehensive review of the epidemiology and pathophysiology by which alcohol may be responsible for AF and determine whether alcohol abstinence is required for patients with AF.
Atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) frequently coexist, and each complicates the course and treatment of the other. Recent population-based studies have ...demonstrated that the 2 conditions together increase the risk of stroke, heart failure hospitalization, and all-cause mortality, especially soon after the clinical onset of AF. Guideline-directed pharmacological therapy for HFrEF is important; however, although there are various treatment modalities for AF, there is no clear consensus on how best to treat AF with concomitant HFrEF. This in-depth review discusses the available data for the treatment of AF in the setting of HFrEF, focuses on areas where more investigation is necessary, examines the clinical implications of randomized and observational clinical trials, and presents suggestions for individualized treatment strategies for specific patient groups.
PDF
