Atrial fibrillation and heart failure in the elderly

Aged gut microbiota promotes arrhythmia susceptibility via oxidative stress

Arrhythmias and sudden cardiac death (SCD) impose a significant burden. Their prevalence rises with age and is linked to gut dysbiosis. Our study aimed to determine whether aged gut microbiota affects arrhythmogenesis. Here, we demonstrated that arrhythmia susceptibility in aged mice could be transmitted to young mice using fecal microbiota transplantation (FMT). Mechanistically, increased intestinal reactive oxygen species (ROS) in aged mice reduced ion channel protein expression and promoted arrhythmias. Gut microbiota depletion by an antibiotic cocktail reduced ROS and arrhythmia in aged mice. Interestingly, oxidative stress in heart induced by hydrogen peroxide (H2O2) increased arrhythmia. Moreover, aged gut microbiota could induce oxidative stress in young mice colon by gut microbiota metabolites transplantation. Vitexin could reduce aging and arrhythmia through OLA1-Nrf2 signaling pathway. Overall, our study demonstrated that the gut microbiota of aged mice reduced cardiac ion channel protein expression through systemic oxidative stress, thereby increased the risk of arrhythmias.

Heart failure in older patients with atrial fibrillation: incidence and risk factors

INTRODUCTION AND OBJECTIVES

Atrial fibrillation (AF) is linked to heart failure (HF). However, little has been published on the factors that may precipitate the onset of HF in AF patients. We aimed to determine the incidence, predictors, and prognosis of incident HF in older patients with AF with no prior history of HF.

METHODS

Patients with AF older than 80 years and without prior HF were identified between 2014 and 2018.

RESULTS

A total of 5794 patients (mean age, 85.2±3.8 years; 63.2% women) were followed up for 3.7 years. Incident HF, predominantly with preserved left ventricular ejection fraction, developed in 33.3% (incidence rate, 11.5-100 people-year). Multivariate analysis identified 11 clinical risk factors for incident HF, irrespective of HF subtype: significant valvular heart disease (HR, 1.99; 95%CI, 1.73-2.28), reduced baseline left ventricular ejection fraction (HR, 1.92; 95%CI, 1.68-2.19), chronic pulmonary obstructive disease (HR, 1.59; 95%CI, 1.40-1.82), enlarged left atrium (HR 1.47, 95%CI 1.33-1.62), renal dysfunction (HR 1.36, 95%CI 1.24-1.49), malnutrition (HR, 1.33; 95%CI, 1.21-1.46), anemia (HR, 1.30; 95%CI, 1.17-1.44), permanent AF (HR, 1.15; 95%CI, 1.03-1.28), diabetes mellitus (HR, 1.13; 95%CI, 1.01-1.27), age per year (HR, 1.04; 95%CI, 1.02-1.05), and high body mass index for each kg/m2 (HR, 1.03; 95%CI, 1.02-1.04). The presence of incident HF nearly doubled the mortality risk (HR, 1.67; 95%CI, 1.53-1.81).

CONCLUSIONS

The presence of HF in this cohort was relatively frequent and nearly doubled the mortality risk. Eleven risk factors for HF were identified, expanding the scope for primary prevention among elderly patients with AF.

Global, regional, and national burden of heart failure associated with atrial fibrillation

BACKGROUND

Heart failure is a leading cause of mortality and morbidity worldwide, and Atrial fibrillation (AF) is among many modifiable risk factors for heart failure. No estimates are available on the magnitude of the burden of heart failure associated with AF, and this study estimated the global, regional, and national burdens associated with AF.

METHODS

We used the comparative risk assessment method to estimate the disease burden in terms of prevalence and years lived with disability (YLD). The population-attributable fraction for heart failure and AF was calculated from prevalence estimates of AF and the recalculated relative risks of heart failure associated with AF from a systematic review summarising the longitudinal association between AF and outcomes. The burden of heart failure was retrieved from the Global Burden of Disease database.

RESULTS

Globally, 2.6% (95% uncertainty interval 1.3 to 4.7%) of the burden of heart failure is associated with AF. This was 1.5 (95% UI 0.6 to 3.2) million people in 2019, a 49.8% increase from 1990. The highest prevalence was from South-East Asia, East Asia and Oceania. The highest YLD was estimated for Central Europe, Eastern Europe and Central Asia. High-income countries showed a sharp decline in the age standardised prevalence and YLD rates from 1990 to 2019.

CONCLUSION

The burden of heart failure associated with AF has increased substantially over the past two decades despite the advances in AF management. However, falling prevalence and YLD rates of heart failure associated with AF in high-income countries over time indicate that reducing this burden is possible.

One-year outcomes of catheter ablation for atrial fibrillation in young patients

BACKGROUND

Atrial fibrillation (AF) is relatively less frequent in younger patients (age < 50). Recently, studies have suggested that early restoration of sinus rhythm may lead to improved outcomes compared with rate control, however the efficacy of catheter ablation for AF in young is scarce.

METHODS

We included all hospitalized patients between 18 and 50 years with a diagnosis of AF from the Nationwide Readmission Database 2016-2017 from the Healthcare Cost and Utilization Project. Demographic and comorbidity data were collected and analyzed. Outcomes assessed included one-year AF readmission rates, all-cause readmission, ischemic stroke, and all-cause mortality. Subgroup analyses were performed for all demographic and comorbidity variables.

RESULTS

Overall, 52,598 patients (medium age 44, interquartile range 38-48, female 25.7%) were included in the study, including 2,146 (4.0%) who underwent catheter ablation for AF. Patients who underwent catheter ablation had a significantly lower rate of readmission for AF or any cause at one year (adjusted hazard ratios (HR) of 0.52 [95% confidence interval (CI): 0.43-0.63] and HR of 0.81 [95% CI: 0.72-0.89], respectively). There was no difference in 1-year readmission for stroke or all-cause mortality between the two groups. Subgroup analyses showed a consistent reduction in the risk of AF readmission among major demographic and comorbidity subgroups.

CONCLUSION

Catheter ablation in young patients with AF was associated with a reduction in 1-year AF related and all-cause readmissions. These data merit further prospective investigation for validation, through dedicated registries and multicenter collaborations to include young AF from diverse population.

Efficacy and safety of high-power short duration atrial fibrillation ablation in elderly patients

INTRODUCTION

Data about atrial fibrillation (AF) ablation using high-power short duration (HPSD) radiofrequency ablation in the elderly population is still scarce. The aim of our study was to investigate the efficacy and safety of HPSD ablation in patients over 75 years compared to younger patients.

METHODS

Consecutive patients older than 75 years with paroxysmal or persistent AF undergoing a first-time AF ablation using 50 W HPSD ablation approach were analyzed in this retrospective observational analysis and compared to a control group <75 years. Short-term endpoints included intraprocedural reconnection of at least one pulmonary vein (PV) and intrahospital and AF recurrence during 3 months blanking period, as well as a long-term endpoint of freedom from atrial arrhythmias of antiarrhythmic drugs after 12 months.

RESULTS

A total of 540 patients underwent a first AF ablation with HPSD (66 ± 10 years; 58% male; 47% paroxysmal AF). Mean age was 78 ± 2.4 and 63 ± 6.3 years (p < .001), respectively. Elderly patients were significantly more often women (p < .001). The procedure, fluoroscopy, and ablation were comparable. Elderly patients revealed significantly more often extra-PV low-voltage areas requiring additional left atrial ablations (p < .001). Overall complication rates were low; however, elderly patients revealed higher major complication rates mainly due to unmasking sick sinus syndrome (p = .003). Freedom from arrhythmia recurrences was comparable (68% vs. 76%, log-rank p = .087). Only in the subgroup of paroxysmal AF, AF recurrences were more common after 12 months (69% vs. 82%; log-rank p = .040; hazard ratio: 1.462, p = .044) in the elderly patients. In multivariable Cox regression analysis of the whole cohort persistent AF, female gender, diabetes mellitus and presence of left atrium low-voltage areas, but not age >75 years were associated with AF recurrences.

CONCLUSION

HPSD AF ablation of patients >75 years in experienced centers is safe and effective. Therefore, age alone should not be the reason to withhold AF ablation from vital elderly patients due to only a slightly worse outcome and safety profile. In paroxysmal AF, elderly patients have more recurrences compared to the younger control group.

Utilization of Digoxin among Hospitalized Older Patients with Heart Failure and Atrial Fibrillation in Thailand: Prevalence, Associated Factors, and Clinical Outcomes

Background

Digoxin is used to control heart rate in patients with heart failure (HF) and atrial fibrillation (AF). However, its use is often limited in older patients, as they are prone to digoxin toxicity. This study aimed to determine the prevalence of digoxin use, investigate the factors associated with digoxin use, and explore the association between digoxin use and clinical outcomes in older Thai patients with HF and AF.

Methods

This cross-sectional study used data obtained from an electronic medical records database. We performed logistic regression analysis to determine the prevalence of digoxin use at index discharge and the factors associated with its use. The Cox proportional hazard model was used to determine the association of all-cause mortality and HF rehospitalization with digoxin use.

Results

Of the 640 patients assessed, 107 (16.72%) were prescribed digoxin before discharge. The factors negatively associated with digoxin use included high serum creatinine level (adjusted odds ratio [AOR]=0.38; 95% confidence interval [CI], 0.22–0.65) and ischemic heart disease (IHD) (AOR=0.52; 95% CI, 0.30–0.88). The factors positively associated with digoxin use were the use of diuretics (AOR=2.65; 95% CI, 1.60–4.38) and mineralocorticoid receptor antagonists (MRAs) (AOR=2.24; 95% CI, 1.18–4.27). We observed no significant association between digoxin use and clinical outcomes (adjusted hazard ratio=1.00; 95% CI, 0.77–1.30).

Conclusion

Digoxin use was prevalent among older patients with HF and AF. Patients with high serum creatinine or IHD were less likely to be prescribed digoxin, whereas those using diuretics or MRAs were more likely to be prescribed digoxin. Although digoxin use was not uncommon among older patients, it was prescribed with caution among Thai patients hospitalized with HF and AF.

Clustering demographics and sequences of diagnosis codes

A Relational-Sequential dataset (or RS-dataset for short) contains records comprised of a patients values in demographic attributes and their sequence of diagnosis codes. The task of clustering an RS-dataset is helpful for analyses ranging from pattern mining to classification. However, existing methods are not appropriate to perform this task. Thus, we initiate a study of how an RS-dataset can be clustered effectively and efficiently. We formalize the task of clustering an RS-dataset as an optimization problem. At the heart of the problem is a distance measure we design to quantify the pairwise similarity between records of an RS-dataset. Our measure uses a tree structure that encodes hierarchical relationships between records, based on their demographics, as well as an edit-distance-like measure that captures both the sequentiality and the semantic similarity of diagnosis codes. We also develop an algorithm which first identifies k representative records (centers), for a given k, and then constructs clusters, each containing one center and the records that are closer to the center compared to other centers. Experiments using two Electronic Health Record datasets demonstrate that our algorithm constructs compact and well-separated clusters, which preserve meaningful relationships between demographics and sequences of diagnosis codes, while being efficient and scalable.

Arrhythmia profile and ablation-outcome in elderly women with atrial fibrillation undergoing first catheter ablation

BACKGROUND

This study evaluated the arrhythmia profile and ablation outcome in women with atrial fibrillation (AF) aged ≥75 years.

METHODS

A total of 573 consecutive female patients undergoing first AF ablation were classified into group 1: ≥75 years (n = 221) and group 2: < 75 years (n = 352). Isolation of PVs, posterior wall and superior vena cava was performed in all. Non-PV triggers from other areas were ablated based on operator's discretion.

RESULTS

Group 1 had higher prevalence of hypertension (154 (69.7%) vs. 188 (53.4%), p < .001) and non-paroxysmal AF (136 (61.5%) vs. 126 (35.8%), p < .001). Non-PV triggers were detected in 194 (87.8%) patients from group 1 and 143 (40.6%) from group 2 (p < .001) and were ablated in 152 (68.8%) and 114 (32.4%) from group 1 and 2 respectively. Remaining patients (group 1: 69/221 and group 2: 238/352) received no additional ablation. At 4 years, 109 (49.3%) and 185 (52.6%) from group 1 and 2, respectively, were arrhythmia-free, p = .69. When stratified by ablation-strategy, success-rate was similar across groups in patients receiving non-PV trigger ablation (96 (63.2%) in group 1 and 76 (66.7%) in group 2, p = .61), whereas it was significantly lower in group 1 patients not receiving additional ablation compared to those from group 2 (13 (18.8%) vs. 109 (45.8%), p < .001).

CONCLUSION

Non-paroxysmal AF was more common in women aged ≥75 years. Furthermore, significantly higher number of non-PV triggers were detected in elderly women and ablation of those provided similar ablation success as that in women aged < 75 years.

Predictors of recurrent atrial fibrillation following catheter ablation

INTRODUCTION

Atrial fibrillation (AF) is a complex and multi-factorial rhythm disorder. Catheter ablation is widely used for the management of AF. However, it is limited by relapse of the arrhythmia necessitating repeat procedures.

AREAS COVERED

This review aims to discuss the predictors of post-ablation recurrent AF including age, gender, genetic predisposition, AF type and duration, comorbidities, lifestyle factors, echocardiographic parameters of heart chambers, left atrial fibrosis and ablation strategies and targets. An extensive literature search was undertaken on PubMed and Google Scholar to obtain full texts of relevant AF-related articles.

EXPERT OPINION

Maintenance of stable sinus rhythm is the main intended outcome of AF ablation. Therefore, it is very crucial to identify the risk factors that may influence the ablation success. Most of these predictors such as comorbidities, ablation strategy and targets and lifestyle factors are either reversible or modifiable. Thus, not only the awareness of these known risk factors by both patients and their physicians but also future research to identify the unknown predictors are critical to optimize care in this multi-faceted morbidity.

Quantification of peripheral whole blood, cell-free plasma and exosome encapsulated mitochondrial DNA copy numbers in patients with atrial fibrillation

Mitochondrial DNA (mtDNA) copy number changes have been associated with various diseases. Several studies showed that mtDNA content in peripheral blood was associated with oxidative stress and cardiovascular disease. Atrial fibrillation (AF) is one of the severe cardiovascular diseases. We aimed to determine the mtDNA copy numbers in peripheral blood, in cell-free plasma and in exosomes of AF patients and healthy controls. Peripheral blood was drawn from 60 AF patients and 72 healthy controls. DNA was isolated from EDTA blood and plasma. Exosomes were isolated from cell-free plasma and then exosome encapsulated DNA (exoDNA) was extracted. Quantitative-real-time PCR was performed with Human Mitochondrial DNA (mtDNA) Monitoring Primer Set. Statistical analysis of the data was performed. We found statistically significant difference in mtDNA copy numbers in DNA isolated from peripheral whole blood, cell-free plasma and exosome samples of controls' (44.4 ± 18.0, 27.2 ± 30.1, 11.5 ± 8.7), and patients' group (43.4 ± 13.6, 26.2 ± 26.4, 14.5 ± 12.3). However there was no significant difference in mtDNA copy number between the two study groups either in peripheral blood, in cell-free plasma and in exosomes, and even in different sexes and ages. We found the highest copy number of mtDNA in peripheral blood, followed by plasma and exosomes. We did not find differences between patients and controls, neither age nor gender had effect on the mtDNA copy number. According to our results the mtDNA copy numbers did not differ in AF patients.

Atrial fibrillation in aging population

With aging, the pathogenesis processes of atrial fibrillation (AF) are heightened. In this article, we review the mechanisms that predispose elderly patients to AF. We also highlight the unique features in diagnosis, stroke prevention, and treatment strategies for the elderly patient with AF.

Clinical outcomes of radiofrequency catheter ablation of atrial fibrillation in octogenarians-10-year experience of a one high-volume center

BACKGROUND

Prevalence of atrial fibrillation (AF) increases with age. Radiofrequency catheter ablation (RFCA) is an established treatment option superior to antiarrhythmics (AAs). In this study, we investigated safety and efficacy of RFCA of AF in octogenarians.

METHODS

From our database, we extracted procedural and follow-up data for patients ≥ 80 years with symptomatic AF undergoing RFCA and compared this population to RFCA patients ≤ 50 years. All patients underwent pulmonary vein isolation (PVI) supplemented by linear lesions in PVI-nonresponders. Arrhythmia-free survival was assessed using seven day Holter every three months post procedure. All patients completed their 12 months follow-up.

RESULTS

Fifty patients aged ≥ 80 years (80.5 ± 1.6 years) were compared to 259 patients aged ≤ 50 years (43.5 ± 5.5 years). The RFCA complication rate did not vary between groups. No differences in procedural characteristics were seen after being analyzed by type of AF. Among patients with paroxysmal AF, 71.4% octogenarian vs. 84.7% young patients was free of any arrhythmia, without AAs, after single procedure. For non-paroxysmal AF, arrhythmia-free survival without AAs, was considerably lower (58.6% octogenarians vs. 81.2% younger patients, P = 0.023). If AAs were used, arrhythmia-free survival for paroxysmal AF increased to 90.5% and 92.1% in octogenarians and younger patients, respectively; and in non-paroxysmal AF it increased to 79.3% vs. 88.4%.

CONCLUSIONS

RFCA is a safe and effective strategy to achieve normal sinus rhythm in a highly selected group of octogenarians. Paroxysmal AF ablation in octogenarians has similar clinical effectiveness as that seen in much younger patients. Non-paroxysmal AF ablation has lower, but still reasonable clinical effectiveness.

Perioperative Outcomes and Safety of Atrial Fibrillation Catheter Ablation in Octogenarians: A Retrospective Study and Review of the Benefits of Rhythm Control

OBJECTIVES

Catheter ablation for rhythm control has emerged as a successful therapeutic option for the treatment of atrial fibrillation (AF), though it has not been well studied in octogenarians. This study evaluates its safety in octogenarians in a community hospital and reviews the benefits of rhythm control.

METHODS

Among 1,592 patients undergoing AF ablation, 84 octogenarian were identified. The primary outcome was normal sinus rhythm (NSR) on electrocardiogram at discharge. Secondary outcomes were periprocedural complications and markers and risks of reablation compared to younger cohorts.

RESULTS

An NSR on discharge occurred in 83 patients. Three patients required pacing for symptomatic sinus bradycardia, complete heart block, and symptomatic junctional bradycardia, respectively. Reablation for recurrent AF occurred in 23 octogenarians. Using the octogenarians as reference, the relative risk (RR) of 1 reablation was not significantly different among the age groups 70-79, 60-69, and <60 years. The RR of 2 reablations was greater in the octogenarian group (RR 0.26 [95% CI 0.09-0.71, p = 0.008], 0.42 [95% CI 0.17-1.04, p = 0.06], and 0.27 [95% CI 0.1-0.75, p = 0.01], respectively). Coronary artery disease (OR 0.14, 95% CI 0.02-0.68, p = 0.026) and percutaneous coronary intervention (OR 0.13, 95% CI 0.02-0.63, p = 0.021) were markers for reablation.

CONCLUSION

AF catheter ablation achieved an NSR with minimal periprocedural complications. The benefits of rhythm control should be considered in treatment.

A MicroRNA-Transcription Factor Blueprint for Early Atrial Arrhythmogenic Remodeling

Spontaneous self-terminating atrial fibrillation (AF) is one of the most common heart rhythm disorders, yet the regulatory molecular mechanisms underlying this syndrome are rather unclear. MicroRNA (miRNA) transcriptome and expression of candidate transcription factors (TFs) with potential roles in arrhythmogenesis, such as Pitx2, Tbx5, and myocardin (Myocd), were analyzed by microarray, qRT-PCR, and Western blotting in left atrial (LA) samples from pigs with transitory AF established by right atrial tachypacing. Induced ectopic tachyarrhythmia caused rapid and substantial miRNA remodeling associated with a marked downregulation of Pitx2, Tbx5, and Myocd expression in atrial myocardium. The downregulation of Pitx2, Tbx5, and Myocd was inversely correlated with upregulation of the corresponding targeting miRNAs (miR-21, miR-10a/10b, and miR-1, resp.) in the LA of paced animals. Through in vitro transient transfections of HL-1 atrial myocytes, we further showed that upregulation of miR-21 did result in downregulation of Pitx2 in cardiomyocyte background. The results suggest that immediate-early miRNA remodeling coupled with deregulation of TF expression underlies the onset of AF.

Comparison of the clinical features and outcomes in two age-groups of elderly patients with atrial fibrillation

Background

Atrial fibrillation (AF) disproportionately affects older adults. However, direct comparison of clinical features, medical therapy, and outcomes in AF patients aged 65–74 and ≥75 years is rare. The objective of the present study was to evaluate the differences in clinical characteristics and prognosis in these two age-groups of geriatric patients with AF.

Materials and methods

A total of 1,336 individuals aged ≥65 years from a Chinese AF registry were assessed in the present study: 570 were in the 65- to 74-year group, and 766 were in the ≥75-year group. Multivariable Cox hazards regression was performed to analyze the major adverse cardiac events (MACEs) between groups.

Results

In our population, the older group were more likely to have coronary artery disease, hypertension, previous stroke, cognitive disorder, or chronic obstructive pulmonary disease, and the 65- to 74-year group were more likely to have valvular heart disease, left ventricular systolic dysfunction, or sleep apnea. The older patients had 1.2-fold higher mean CHADS₂ (congestive heart failure, hypertension, age ≥75 years, diabetes, stroke) scores, but less probability of being prescribed drugs. Compared with those aged 65–74 years, the older group had a higher risk of death (hazard ratio 2.881, 95% confidence interval 1.981–4.189; P<0.001) or MACE (hazard ratio 2.202, 95% confidence interval 1.646–2.945; P<0.001) at the 1-year follow-up. In multivariable Cox analyses, secondary AF diagnosis, a history of chronic obstructive pulmonary disease, and left ventricular systolic dysfunction were independent predictors of MACE in the older group.

Conclusion

Patients aged ≥75 years had a worse prognosis than those aged 65–74 years, and were associated with a higher risk of both death and MACE.

Heart failure in patients with atrial fibrillation is associated with a high symptom and hospitalization burden: the RealiseAF survey

BACKGROUND

Atrial fibrillation (AF) and heart failure (HF) often coexist; the consequences of such coexistence are unclear.

HYPOTHESIS

HF in patients with AF is associated with poor outcomes.

METHODS

This post hoc analysis of RealiseAF, a survey of AF patients, compared symptoms, hospitalizations, management, and AF control in patients with vs without HF. A total of 10,523 AF patients were analyzed according to presence/absence of HF.

RESULTS

History of HF was present in 45.8%, and in more patients with permanent vs persistent, paroxysmal, or first-episode AF (55.6%, 44.3%, 32.9%, and 29.8%, respectively; P < 0.0001). Patients with vs those without history of HF, and patients with HF and reduced ejection fraction (HF-REF) vs those with HF and a preserved ejection fraction (HF-PEF), had more frequent cardiovascular (CV) risk factors and more severe symptoms. Presence vs absence of HF, and HF-REF vs HF-PEF, were associated with lower rates of AF control (54.6% vs 62.8% and 49.3% vs 60.3%, respectively; both P < 0.0001). The rate-control strategy was used more frequently in HF patients, particularly those with HF-REF, than the rhythm-control strategy. CV hospitalizations occurred more frequently in patients with HF than those without (41.8% vs 17.5%; P < 0.001) and more frequently in patients with HF-REF than in those with HF-PEF (51.6% vs 35.6%; P < 0.0001).

CONCLUSIONS

AF patients with HF, particularly HF-REF, experience heavy symptom and hospitalization burdens, and have relatively low rates of AF control. Further studies are needed to identify ways to improve the management and treatment outcomes of this very high-risk patient population.

Meta-analysis of the therapeutic effects of various methods for the treatment of chronic atrial fibrillation

The aim of this study was to analyze the therapeutic effects of various methods for the treatment of chronic atrial fibrillation (AF). Randomized controlled trials (RCT) concerning drug therapy and catheter ablation for the treatment of chronic AF were retrieved. The RevMan 5.1 software package was used for the meta-analysis. A total of 20 papers were assessed in this study. The results of the analysis indicated that the success rate was lower [odds ratio (OR), 8.94; 95% confidence interval (CI), 4.70-17.02; P<0.0001] and the relapse rate was higher (OR, 0.07, 95% CI, 0.05-0.10; P<0.0001) for drug therapy compared with that for catheter ablation. With regard to different catheter ablation procedures, the success rate for pulmonary vein antrum isolation (PVAI) was lower compared with that for PVAI plus complex fractionated atrial electrogram (CFAE; OR, 0.53; 95% CI, 0.37-0.78; P=0.0001). Pulmonary vein isolation (PVI) plus left atrial ablation (LAA) had a higher success rate compared with PVI alone (OR, 2.79; 95% CI, 1.59-4.88, P=0.0003). There was not identified to be a significant difference in the success rates between PVAI and CFAE (OR, 2.05; 95% CI, 0.06-205.74; P=0.76) or between PVI and circumferential pulmonary vein isolation (CPVI; OR, 0.94; 95% CI, 0.29-3.00; P=0.91). All the funnel plots of publication bias were essentially symmetrical. In conclusion, the success rate was higher and the relapse rate was lower for catheter ablation compared with drug therapy. Among the different procedures of catheter ablation, there were no significant differences in success rate between two single procedures; however, the success rates were higher for the combined methods compared with those for the single methods.

Heart failure in elderly patients: distinctive features and unresolved issues

The prevalence of heart failure (HF) increases with age. While clinical trials suggest that contemporary evidence-based HF therapies have reduced morbidity and mortality, these trials largely excluded the elderly. Questions remain regarding the clinical characteristics of elderly HF patients and the impact of contemporary therapies on their outcomes. This review presents the epidemiology of HF in the elderly and summarizes the data on the pathophysiology of the ageing heart. The clinical characteristics, treatment patterns, and outcomes of elderly HF patients are explored. Finally, the main gaps regarding HF therapies in the elderly and the opportunities for future trials are highlighted.

The use of ω-3 poly-unsaturated fatty acids in heart failure: a preferential role in patients with diabetes

PURPOSE

To review the evidence for a beneficial effect of ω-3 PUFAs in heart failure (HF) and its co-morbidities, their possible preferential effect in diabetes and the potential mechanism for their benefit.

METHODS

We summarize the clinical studies which investigated the use of ω-3 PUFAs in patients with HF with an emphasis on diabetes. We briefly summarize the evidence for an effect of ω-3 PUFAs in patients with coronary artery disease (CAD), atrial fibrillation (AF) and ventricular arrhythmias. We also discuss the proposed mechanisms of ω-3 PUFA action in cardiovascular diseases.

RESULTS

While there is emerging evidence for a beneficial effect of ω-3 PUFA supplementation in patients with HF, the evidence for other indications have been variable and conflicting. In HF patients with diabetes, ω-3 PUFAs may have a preferential therapeutic benefit. Randomized controlled trials did not show considerable beneficial effects of ω-3 PUFAs in other conditions such as CAD and AF. In a diabetic and insulin-resistant state, ω-3 PUFAs bind to the G-protein coupled receptor, GPR120, resulting in reduced cytokine production from inflammatory macrophages and improved signaling in adipocytes, leading to a reduction in insulin resistance.

CONCLUSIONS

There is promising evidence showing that use of ω-3 PUFA supplementation improves clinical outcomes of HF patients with diabetes. Further clinical trials are needed in this regard.