Patients Treated with Catheter Ablation for Atrial Fibrillation Have Long-Term Rates of Death, Stroke, and Dementia Similar to Patients Without Atrial Fibrillation

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Assessment of atrial fibrillation ablation outcomes with clinic ECG, monthly 24-h Holter ECG, and twice-daily telemonitoring ECG

Differences in the methodologies for evaluating atrial fibrillation (AF) ablation outcomes should be evaluated. In the present study, we compared the AF ablation outcomes among periodic clinic electrocardiography (ECG), 24-h Holter ECG, and telemonitoring ECG to evaluate the differences among these methods. In addition, we evaluated the AF-free survival rate for each method with different durations of the blanking period. A total of 30 AF patients were followed up for 6 months after initial catheter ablation, with clinic ECG on every clinic visit, monthly 24-h Holter ECG, and telemonitoring ECG twice daily and upon symptoms. AF relapse was defined as AF or atrial tachycardia detected with any of the methods. Two patients dropped out of the study, and 28 patients were followed up for 8.8 ± 2.7 months. Patients underwent 3.6 ± 0.8 clinic ECG, 5.1 ± 0.8 Holter ECG, and 273 ± 68 telemonitoring ECG examinations. During the first, second, third, fourth, fifth, and sixth months of follow-up, Holter ECG detected relapses in 11.1, 8.3, 11.5, 15.4, 4.2, and 4.8 % of patients and telemonitoring ECG detected relapses in 32.1, 25.0, 25.0, 17.9, 28.6, and 17.9 % of patients, respectively. When no duration was set for the blanking period, the AF-free survival rate was significantly lower with telemonitoring ECG (46.4 %) than with Holter ECG (78.6 %, P = 0.013) or clinic ECG (85.7 %, P = 0.002). In addition, when the duration of the blanking period was set to 3 months, the AF-free survival rate was significantly lower with telemonitoring ECG than with clinic ECG (92.9 vs. 71.4 %, P = 0.041). The AF ablation outcomes with twice-daily telemonitoring ECG might differ from those with clinic ECG when the duration of the blanking period is 0-3 months. A follow-up based solely on clinic ECG might underestimate AF recurrence.

The Mechanism of and Preventive Therapy for Stroke in Patients with Atrial Fibrillation

Atrial fibrillation is a major cardiac cause of stroke, and a pathogenesis involving thrombus formation in patients with atrial fibrillation is well established. A strategy for rhythm control that involves catheter ablation and anticoagulation therapy is evolving. A strategy for rhythm control that restores and maintains sinus rhythm should reduce the risk of ischemic stroke that is associated with atrial fibrillation; however, this is yet to be proven in large-scale randomized controlled trials. This paper reviews the emerging role of rhythm control therapy for atrial fibrillation to prevent stroke.

Diagnostic Evaluation and Follow-Up of Patients with Atrial Fibrillation

In this article, a review of the diagnostic evaluation and outpatient follow-up of patients with atrial fibrillation is presented. After exploring details of symptoms, past medical history, quality of life, and physical exam findings, diagnostic tools are then discussed. Furthermore, important considerations after the initial diagnosis and treatment of patients with atrial fibrillation are discussed.

A cost-utility analysis for catheter ablation of atrial fibrillation in combination with warfarin and dabigatran based on the CHADS2 score in Japan

BACKGROUND

We aimed to clarify the cost-effectiveness of an expensive combination therapy for atrial fibrillation (AF) using both catheter ablation and dabigatran compared with warfarin at each CHADS₂ score for patients in Japan.

METHODS

A Markov model was constructed to analyze costs and quality-adjusted life years associated with AF therapeutic options with a time horizon of 10 years. The target population was 60-year-old patients with paroxysmal AF. The indication for anticoagulation was determined according to the Japanese guideline. Anticoagulation-related data were derived from the RE-LY study and the AF recurrence rate was set at 2.7% per month during the first 12 months and at 0.40% per month afterwards. Stroke risk was determined according to AF recurrence, anticoagulation, and CHADS₂ score. The risks for stroke recurrence and stroke death were also considered. Costs were calculated from the healthcare payer's perspective, and only direct medical costs were included.

RESULTS

Warfarin was the most preferred option for patients with a CHADS₂ score of 0 from a health economics aspect. Ablation under warfarin was preferred for a CHADS₂ score of 1-3, while ablation under dabigatran was preferred for a CHADS₂ score ≥4. The quality of life score for AF had the largest impact on the incremental cost-effectiveness ratios in the analysis between the anticoagulation arm and the anticoagulation+ablation arm for a CHADS₂ score of 2. Within the range of the Japanese willingness-to-pay threshold (¥5,000,000), the ablation+warfarin arm became the best option with its probability of 81.7% for a CHADS₂ score of 2; the dabigatran+ablation arm was the most preferred option with its probability of 56.1% for a CHADS₂ score of 4.

CONCLUSIONS

Ablation under dabigatran therapy is an expensive therapeutic option, but it might benefit patients with a low quality of life and a high CHADS₂ score.

Atrial Fibrillation and Risk of Dementia/Cognitive Decline

Emerging evidence suggests a link between atrial fibrillation and subsequent development of dementia. While a majority of risk can be attributed to cardioembolic stroke secondary to atrial fibrillation, additional risk is apparent, and may be driven by vascular inflammation and changes in cerebral perfusion. Medical therapies including anticoagulation, statin therapy, and angiotensin-renin-aldosterone axis antagonists may reduce dementia risk. Procedural therapies such as atrial fibrillation catheter ablation and left atrial appendage closure may also prove to be important mediators of acute and long-term risk. In this paper, we review the data supporting a link between atrial fibrillation and dementia syndromes, pathophysiologic mechanisms and the potential roles of medical and procedural therapies at reducing such risk.

A Patient With Asymptomatic Cerebral Lesions During AF Ablation: How Much Should We Worry?

Silent brain lesions due to thrombogenicity of the procedure represent recognized side effects of atrial fibrillation (AF) catheter ablation. Embolic risk is higher if anticoagulation is inadequate and recent studies suggest that uninterrupted anticoagulation, ACT levels above 300 seconds and administration of a pre-transeptal bolus of heparin might significantly reduce the incidence of silent cerebral ischemia (SCI) to 2%. Asymptomatic new lesions during AF ablation should suggest worse neuropsychological outcome as a result of the association between silent cerebral infarcts and increased long-term risk of dementia in non-ablated AF patients. However, the available data are discordant. To date, no study has definitely linked post-operative asymptomatic cerebral events to a decline in neuropsychological performance. Larger volumes of cerebral lesions have been associated with cognitive decline but are uncommon findings acutely in post-ablation AF patients. Of note, the majority of acute lesions have a small or medium size and often regress at a medium-term follow-up. Successful AF ablation has the potential to reduce the risk of larger SCI that may be considered as part of the natural course of AF. Although the long-term implications of SCI remain unclear, it is conceivable that strategies to reduce the risk of SCI may be beneficial.

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.

Differences in Quality of Life Between Atrial Fibrillation Patients with Low Stroke Risk Treated With and Without Catheter Ablation

BACKGROUND

Impacts of a single radiofrequency ablation (RFA) on quality of life (QoL) were not well investigated in atrial fibrillation (AF) patients with low stroke risk.

METHODS AND RESULTS

Nine hundred AF patients with low CHADS2 score (ie, CHADS2 ≤1) who completed both a baseline and 6-month Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) questionnaire were selected from The Chinese Atrial Fibrillation Registry between 2011 and 2013. A final cohort of 222 patients was constructed after a propensity score matching with 74 in the RFA group and 148 in the non-RFA group. Domains of AFEQT were balanced at baseline between the 2 groups. No statistically significant differences were noted in QoL (all P>0.05) when AFEQT at 6 months was compared between groups, except for the symptoms domain (83.07±12.37 units in the RFA group vs. 77.68±17.14 units in the non-RFA group; P=0.008) and treatment satisfaction domain (76.34±14.92 units in the RFA group vs. 70.38±16.81 units in the non-RFA group; P=0.01). Within-group changes in all domains and the global score of the questionnaire were moderate to large, whereas between-group comparisons in baseline to 6-month changes and QoL at 6 months were small to moderate according to Cohen effect sizes.

CONCLUSIONS

QoL was balanced at baseline and improved at 6 months in both groups from this observational propensity-matched cohort based on the AFEQT questionnaire. However, RFA treatment was only associated with small-to-moderate superiorities over non-RFA treatment. The role of RFA in QoL improvement among AF patients with low stroke risk requires further research.

Prediction of improvement in left atrial function index after catheter ablation for atrial fibrillation

PURPOSE

Although left atrial function index is reportedly a possible predictor of hospitalization for heart failure and of stroke irrespective of the presence or not of atrial fibrillation (AF), the effects of catheter ablation on left atrial function index have not yet been reported.

METHODS

We performed catheter ablation on 55 patients (age 56.6 ± 9.6 years; 44 men; 30 with paroxysmal and 25 with persistent, long-standing AF) and evaluated them by transthoracic echocardiography preoperatively and 3 monthly for 12-24 months after catheter ablation. We then compared clinical characteristics and echocardiographic variables before catheter ablation between two groups: the 42 subjects with the most recent left atrial function index <30 and the 13 in which it was ≥30.

RESULTS

Left atrial function index improved after catheter ablation in both groups, plateauing 6 months after the procedure. Univariate analysis showed statistically significant differences in the prevalence of chronic AF and left atrial emptying fraction, diameter, and maximum and minimum volume (prevalence of chronic AF, p < 0.05; others, p < 0.01) between the groups. Multivariate analysis showed that only maximum left atrial volume predicts left atrial function index after catheter ablation (p < 0.05). In addition, we used ROC analysis to calculate a cutoff value for LA maximum volume as a good predictor and found that a good cutoff value was 63.5 mL, the sensitivity and specificity being 0.75 and 0.75, respectively.

CONCLUSIONS

Catheter ablation improves left atrial function index. However, in patients with left atrial maximum volume of over 63.5 mL on echocardiography, the index did not recover to within the normal range after catheter ablation.

Intermediate- and Long-Term Cognitive Outcomes After Cardiovascular Procedures in Older Adults: A Systematic Review

BACKGROUND

Risks for intermediate- and long-term cognitive impairment after cardiovascular procedures in older adults are poorly understood.

PURPOSE

To summarize evidence about cognitive outcomes in adults aged 65 years or older at least 3 months after coronary or carotid revascularization, cardiac valve procedures, or ablation for atrial fibrillation.

DATA SOURCES

MEDLINE, Cochrane, and Scopus databases from 1990 to January 2015; ClinicalTrials.gov; and bibliographies of reviews and eligible studies.

STUDY SELECTION

English-language trials and prospective cohort studies.

DATA EXTRACTION

One reviewer extracted data, a second checked accuracy, and 2 independently rated quality and strength of evidence (SOE).

DATA SYNTHESIS

17 trials and 4 cohort studies were included; 80% of patients were men, and mean age was 68 years. Cognitive function did not differ after the procedure between on- and off-pump coronary artery bypass grafting (CABG) (n = 6; low SOE), hypothermic and normothermic CABG (n = 3; moderate to low SOE), or CABG and medical management (n = 1; insufficient SOE). One trial reported lower risk for incident cognitive impairment with minimal versus conventional extracorporeal CABG (risk ratio, 0.34 [95% CI, 0.16 to 0.73]; low SOE). Two trials found no difference between surgical carotid revascularization and carotid stenting or angioplasty (low and insufficient SOE, respectively). One cohort study reported increased cognitive decline after transcatheter versus surgical aortic valve replacement but had large selection and outcome measurement biases (insufficient SOE).

LIMITATIONS

Mostly low to insufficient SOE; no pertinent data for ablation; limited generalizability to the most elderly patients, women, and persons with substantial baseline cognitive impairment; and possible selective reporting and publication bias.

CONCLUSION

Intermediate- and long-term cognitive impairment in older adults attributable to the studied cardiovascular procedures may be uncommon. Nevertheless, clinicians counseling patients before these procedures should discuss the uncertainty in their risk for adverse cognitive outcomes.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Different distribution of Helicobacter pylori EPIYA- cagA motifs and dupA genes in the upper gastrointestinal diseases and correlation with clinical outcomes in iranian patients

AIM

Our aim was to determine the EPIYA-cagA Phosphorylation sites and dupA gene in H. pylori isolates among patients with upper gastrointestinal diseases.

BACKGROUND

Pathogenicity of the cagA-positive Helicobacter pylori is associated with EPIYA motifs and higher number of EPIYA-C segments is a risk factor of gastric cancer, while duodenal ulcer-promoting gene (dupA) is determined as a protective factor against gastric cancer.

PATIENTS AND METHODS

A total of 280 non-repeated gastric biopsies obtained from patients undergoing endoscopy from January 2013 till July 2013. Samples were cultured on selective horse blood agar and incubated in microaerophilic atmosphere. The isolated organisms were identified as H. pylori by Gram staining and positive oxidase, catalase, and urease tests. Various motif types of cagA and the prevalence of dupA were determined by PCR method.

RESULTS

Out of 280 specimens, 128 (54.7%) isolated organisms were identified as H. pylori. Of 120 H. pylori isolates, 35.9% were dupA positive and 56.26% were cagA positive, while cagA with ABC and ABCC motifs were 55.5% and 44.5%, respectively. Fifty six percent of the isolates with the ABCC motif have had dupA genes. We also found a significant association between strains with genotypes of dupA-ABC and duodenal ulcer disease (p = 0.007).

CONCLUSION

The results of this study showed that the prevalence of cagA-positive H. pylori in Shiraz was as high as in western countries and higher numbers of EPIYA-C segments were seen in gastric cancer patients. We may also use dupA as a prognostic and pathogenic marker for duodenal ulcer disease and cagA with the segment C for gastric cancer and gastric ulcer disease in this region.

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.

Optimization of catheter ablation of atrial fibrillation: insights gained from clinically-derived computer models

Atrial fibrillation (AF) is the most common heart rhythm disturbance, and its treatment is an increasing economic burden on the health care system. Despite recent intense clinical, experimental and basic research activity, the treatment of AF with current antiarrhythmic drugs and catheter/surgical therapies remains limited. Radiofrequency catheter ablation (RFCA) is widely used to treat patients with AF. Current clinical ablation strategies are largely based on atrial anatomy and/or substrate detected using different approaches, and they vary from one clinical center to another. The nature of clinical ablation leads to ambiguity regarding the optimal patient personalization of the therapy partly due to the fact that each empirical configuration of ablation lines made in a patient is irreversible during one ablation procedure. To investigate optimized ablation lesion line sets, in silico experimentation is an ideal solution. 3D computer models give us a unique advantage to plan and assess the effectiveness of different ablation strategies before and during RFCA. Reliability of in silico assessment is ensured by inclusion of accurate 3D atrial geometry, realistic fiber orientation, accurate fibrosis distribution and cellular kinetics; however, most of this detailed information in the current computer models is extrapolated from animal models and not from the human heart. The predictive power of computer models will increase as they are validated with human experimental and clinical data. To make the most from a computer model, one needs to develop 3D computer models based on the same functionally and structurally mapped intact human atria with high spatial resolution. The purpose of this review paper is to summarize recent developments in clinically-derived computer models and the clinical insights they provide for catheter ablation.

Radiofrequency catheter ablation for atrial fibrillation

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

Atrial fibrillation: A major risk factor for cognitive decline

Atrial fibrillation is a common disease of the elderly, conferring considerable morbidity and mortality related to cardiovascular effects and thromboembolic risks. Anticoagulation, antiarrhythmic medications, and rate control are the cornerstone of contemporary management, whereas ablation and evolving surgical techniques continue to play important secondary roles. Growing evidence shows that atrial fibrillation is also a risk factor for significant cognitive decline through a multitude of pathways, further contributing to morbidity and mortality. At the same time, cognitive decline associated with cryptogenic strokes may be the first clue to previously undiagnosed atrial fibrillation. These overlapping associations support the concept of cognitive screening and rhythm monitoring in these populations. New research suggests modulating effects of currently accepted treatments for atrial fibrillation on cognition; however, there remains the need for large multicenter studies to examine the effects of novel oral anticoagulants, rhythm and rate control, and left atrial appendage occlusion on long-term cognitive function.

What can rhythm control therapy contribute to prognosis in atrial fibrillation?

Atrial fibrillation (AF) is a global healthcare problem of growing prevalence and major significance. The consequences of AF include an increased rate of death, stroke and heart failure. Theoretically, a therapeutic strategy aiming at restoration and maintenance of sinus rhythm should offset the prognosis impairment associated with AF. However, these expectations were disproven in large randomised controlled trials comparing conventional antiarrhythmic drugs for rhythm control with conventional rate control. These apparently contradictory findings suggest that rhythm control strategies require better therapeutic instruments. These improvements may involve drugs and/or interventions with optimised risk-benefit profile and which also appreciate the specific atrial pathology and the patient's comorbidities. This article addresses important aspects of rhythm control strategies, which may have the potential of a beneficial contribution to the prognosis of AF patients.

Target risk factors for dementia prevention: a systematic review and Delphi consensus study on the evidence from observational studies

OBJECTIVE

Dementia has a multifactorial etiology, but the importance of individual health and lifestyle related risk factors is often uncertain or based on few studies. The goal of this paper is to identify the major modifiable risk factors for dementia as a first step in developing an effective preventive strategy and promoting healthy late life cognitive functioning.

METHODS

A mixed-method approach combined findings from a systematic literature review and a Delphi consensus study. The literature search was conducted in PubMed and updated an earlier review by the United States National Institutes of Health from 2010. We reviewed the available evidence from observational epidemiological studies. The online Delphi study asked eight international experts to rank and weigh each risk factor for its importance for dementia prevention.

RESULTS

Out of 3127 abstracts, 291 were included in the review. There was good agreement between modifiable risk factors identified in the literature review and risk factors named spontaneously by experts. After triangulation of both methods and re-weighting by experts, strongest support was found for depression, (midlife) hypertension, physical inactivity, diabetes, (midlife) obesity, hyperlipidemia, and smoking, while more research is needed for coronary heart disease, renal dysfunction, diet, and cognitive activity.

CONCLUSIONS

Findings provide good support for several somatic and lifestyle factors and will be used to inform the design of a new multicenter trial into dementia prevention.

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.

Untreated atrial fibrillation in the United Kingdom: Understanding the barriers and treatment options

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major preventable cause of stroke and hospitalization. Its prevalence is on the rise worldwide and experts believe it will continue to rise for the foreseeable future, due to the ageing population and increased survival from conditions associated with AF. Despite the fact that oral anticoagulation is effective in preventing strokes due to AF, there is extensive evidence suggesting this therapy remains underused. Barriers to the prescription of anticoagulation include patients' age per se, comorbidities, inadequate risk stratification, perceived risk of falls and bleeding, and the difficulty in achieving a stable international normalized ratio (INR) on warfarin. Also, asymptomatic patients with AF may not be identified and therefore not be candidates for anticoagulation. Physicians need continued better education on the identification of patients at risk of stroke and management of oral anticoagulation. This article reviews the barriers to anticoagulation in patients with AF in the United Kingdom and considers how those barriers may be overcome.

The impact of risk score (CHADS2 versus CHA2DS2-VASc) on long-term outcomes after atrial fibrillation ablation

BACKGROUND

Risk stratification tools are needed to select the right candidates for catheter ablation of atrial fibrillation (AF). Both the CHADS2 and CHA2DS2-VASc scores have utility in predicting AF-related outcomes and guiding anticoagulation treatment.

OBJECTIVE

We sought to determine whether these risk scores predict long-term outcomes after AF ablation and whether one risk score provides comparatively superior performance.

METHODS

CHADS2 and CHA2DS2-VASc scores were calculated in 2179 patients who underwent a first ablation procedure for AF enrolled in the Intermountain Heart Collaborative Study. CHADS2 and CHA2DS2-VASc scores were categorized as 0-1, 2-4, and ≥5. Patient outcomes were analyzed over 5 years for AF/atrial flutter recurrence and major adverse cardiovascular events (MACE: composite of death, stroke, and heart failure hospitalization).

RESULTS

The mean age was 65.7 ± 10.5 years, and 61.1% were men. Both scores incrementally predicted risk of AF recurrence, stroke, heart failure, and death at 5 years. Increasing CHADS2 (hazard ratio [HR] 1.19; P < .001) and CHA2DS2-VASc (HR 1.15; P < .0001) scores were both associated with AF/atrial flutter recurrence. The results were similar for MACE where increasing CHADS2 (HR 1.54; P < .0001) and CHA2DS2-VASc (HR 1.32; P < .0001) scores were associated with risk. When CHADS2 and CHA2DS2-VASc scores were modeled together, only CHA2DS2-VASc scores significantly predicted AF recurrence (HR 1.13; P = .001), but both were associated with MACE.

CONCLUSION

Both the CHADS2 and CHA2DS2-VASc scores were excellent in stratifying patients for 5-year outcomes after AF ablation. However, the CHA2DS2-VASc score was superior to the CHADS2 score in predicting AF recurrence and AF-related morbidities.

Diagnostic evaluation and follow-up of patients with atrial fibrillation

In this article, a review of the diagnostic evaluation and outpatient follow-up of patients with atrial fibrillation is presented. After exploring details of symptoms, past medical history, quality of life, and physical exam findings, diagnostic tools are then discussed. Furthermore, important considerations after the initial diagnosis and treatment of patients with atrial fibrillation are discussed.