Role of inflammation in initiation and perpetuation of atrial fibrillation: a systematic review of the published data

Cardiovascular Manifestations of Inflammatory Bowel Disease: Pathogenesis, Diagnosis, and Preventive Strategies

Inflammatory bowel disease (IBD) refers to a group of chronic inflammatory diseases that targets mainly the gastrointestinal tract. The clinical presentation of IBD includes both gastrointestinal manifestations and extraintestinal manifestations (EIM). The reported cardiovascular manifestations in IBD patients include pericarditis, myocarditis, venous and arterial thromboembolism, arrhythmias, atrioventricular block, heart failure, endocarditis, valvulopathies, and Takayasu arteritis. The aim of this article is to review the available literature about the possible pathogenic mechanisms and determine preventive measures capable of reducing the incidence and severity of the cardiovascular manifestations. In IBD patients, the incidence of cardiovascular manifestations is low, but higher than that in the general population. Therefore, clinicians should pay attention to any new modification that might indicate cardiovascular involvement in IBD patients, and they should consider chronic inflammatory diseases in patients with cardiac conditions without an evident cause. Considering the role of inflammation in the development of cardiovascular manifestations, the management should include prevention of flares and maintenance of remission for as long as possible. Preventive measures should also include active screening and strict control of the cardiovascular risk factors in all IBD patients.

Biomarkers Determining Prognosis of Atrial Fibrillation Ablation

Catheter ablation for rhythm control is recommended in specific patient populations with paroxysmal, persistent, or long-standing persistent atrial fibrillation. Pulmonary vein isolation is the cornerstone of the ablative therapy for atrial fibrillation. However, relapse is still common since the single procedure efficacy of atrial fibrillation ablation was estimated to be 60-80% in paroxysmal and 50-70% in persistent atrial fibrillation. It is important to identify predictors of successful atrial fibrillation patients ablation. In the present review, we will assess the role of available biomarkers to predict responders of an initial atrial fibrillation catheter ablation. Emphasis has been given on the role of myocardial injury biomarkers, natriuretic peptides and traditional inflammatory markers. Novel inflammatory markers, oxidative stress biomarkers and microRNAs have also been examined as predictors of a successful atrial fibrillation procedure. Notably, the impact of procedural and short-term administration of steroids, as well as the role of colchicine on preventing atrial fibrillation recurrence after ablation is thoroughly presented.

Biomarkers Associated with Atrial Fibrosis and Remodeling

Atrial fibrillation is the most common rhythm disturbance encountered in clinical practice. Although often considered as solely arrhythmic in nature, current evidence has established that atrial myopathy constitutes both the substrate and the outcome of atrial fibrillation, thus initiating a vicious, self-perpetuating cycle. This myopathy is triggered by stress-induced (including pressure/volume overload, inflammation, oxidative stress) responses of atrial tissue, which in the long term become maladaptive, and combine elements of both structural, especially fibrosis, and electrical remodeling, with contemporary approaches yielding potentially useful biomarkers of these processes. Biomarker value becomes greater given the fact that they can both predict atrial fibrillation occurrence and treatment outcome. This mini-review will focus on the biomarkers of atrial remodeling (both electrical and structural) and fibrosis that have been validated in human studies, including biochemical, histological and imaging approaches.

Inflammatory Biomarkers in Atrial Fibrillation

During the last few years, a significant number of studies have attempted to clarify the underlying mechanisms that lead to the presentation of atrial fibrillation (AF). Inflammation is a key component of the pathophysiological processes that lead to the development of AF; the amplification of inflammatory pathways triggers AF, and, in tandem, AF increases the inflammatory state. Indeed, the plasma levels of several inflammatory biomarkers are elevated in patients with AF. In addition, the levels of specific inflammatory biomarkers may provide information regarding to the AF duration. Several small studies have assessed the role of anti-inflammatory treatment in atrial fibrillation but the results have been contradictory. Large-scale studies are needed to evaluate the role of inflammation in AF and whether anti-inflammatory medications should be routinely administered to patients with AF.

Reduction of atrial fibrillation burden by pulmonary vein isolation leads to a decrease of CD11b expression on inflammatory cells

Aims

It is hypothesized that inflammation could promote structural and electrical remodelling processes in atrial fibrillation (AF). Atrial infiltration of monocytes and granulocytes has been shown to be dependent on CD11b expression. The aim of this study was to investigate whether treatment of AF by pulmonary vein isolation (PVI) may lead to reduced inflammation, as indicated by a decrease of CD11b expression on monocytes and granulocytes.

Methods and results

Flow-cytometric quantification analysis and determination of systemic inflammatory markers of peripheral blood were performed in 75 patients undergoing PVI 1 day before and 6 months after PVI. The extent of activation of monocytes and granulocytes was measured by quantifying the cell adhesion molecule CD11b. The mean expression of CD11b on monocytes (20.9 ± 2.5 vs. 10.2 ± 1.4; P < 0.001) and granulocytes (13.9 ± 1.6 vs. 6.8 ± 0.5; P < 0.001), as well as the relative count of CD11b-positive monocytes (P < 0.05) and CD11b-positive granulocytes (P < 0.01) were significantly reduced when comparing the identical patients before and 6 months after PVI. Systemic inflammatory parameters showed only a declining tendency after 6 months. Patients with unsuccessful PVI and ongoing AF on the day of follow-up showed no decrease in CD11b expression.

Conclusions

A significant reduction of CD11b expression on monocytes and granulocytes, as a sign of reduced cellular inflammation, was achieved by treatment of AF using PVI. These data strongly support that AF is not only a consequence of but also a cause for inflammatory processes, which, in turn, may contribute to atrial remodelling.

The relationship between serum indoxyl sulfate and the renal function after catheter ablation of atrial fibrillation in patients with mild renal dysfunction

Indoxyl sulfate (IS), a protein-bound uremic toxin, induces renal disorders and atrial fibrillation (AF). It is well known that renal dysfunction is a risk factor for AF and radiofrequency catheter ablation (RFCA) improves the renal function. However, the improvement in the renal function after RFCA in patients with early stage chronic kidney disease (CKD) and the serial changes in the IS level have not been fully elucidated. This study aimed to investigate whether IS affects the improvement in the renal function. A total of 91 consecutive patients with mild kidney dysfunction (CKD stage I-II) who underwent RFCA and maintained sinus rhythm were prospectively enrolled. The plasma IS level and estimated glomerular filtration rate (eGFR) were determined before, 3 months, and 1 year after RFCA. The patients were divided according to the IS quartiles (Q1-4; < 0.4, 0.4-0.7, 0.7-1.2, and > 1.2 μg/ml). There was no significant difference in the eGFR among the IS quartiles. A significantly higher eGFR improvement rate was obtained for IS-Q4 than the other quartiles (p = 0.039). The IS-Q4 IS level significantly decreased at 1 year after RFCA (1.8 ± 0.8 to 1.2 ± 0.7 μg/ml, p < 0.01). The multivariable logistic model revealed that a high-IS level (IS-Q4) was an independent predictor of an eGFR improvement (OR 3.33; 95% CI 1.16-9.59; p = 0.026). A high-IS level reduction after RFCA improved the renal function in AF patients with mild kidney dysfunction.

Atrial Fibrillation and Acute Myocardial Infarction – An Inflammation-Mediated Association

Atrial fibrillation (AF) is an increasingly widespread healthcare problem. AF can frequently present as a complication in acute coronary syndromes (ACS), especially in ST-elevation acute myocardial infarction (AMI), in which case it is the most frequent supraventricular rhythm disturbance with an estimated incidence of 6.8-21%. The presence of AF in ACS heralds worse outcomes in comparison to subjects in sinus rhythm, and several studies have shown that in AMI patients, both new-onset and pre-existing AF are associated with a higher risk of major adverse cardiovascular and cerebrovascular events during hospitalization. The cause of newonset AF in AMI is multifactorial. Although still incompletely understood, the mechanisms involved in the development of AF in acute myocardial ischemic events include the neurohormonal activation of the sympathetic nervous system that accompanies the AMI, ischemic involvement of the atrial myocytes, ventricular dysfunction, and atrial overload. The identification of patients at risk for AF is of great significance as it may lead to prompt therapeutic interventions and closer follow-up, thus improving prognosis and decreasing cardiovascular and cerebrovascular events. The present manuscript aims to summarize the current research findings related to new-onset AF in AMI patients, as well as the predictors and prognostic impact of this comorbid association.

Steroids prevent early recurrence of atrial fibrillation following catheter ablation: a systematic review and meta-analysis

Previous studies have reported that steroids may reduce the risk of atrial fibrillation (AF) recurrence after catheter ablation, but data regarding this issue have been controversial. Therefore, we conducted a meta-analysis of randomized clinical trials (RCTs) and observational studies to ascertain the association of steroids and AF recurrence after ablation. PubMed, Embase, and Cochrane online databases were searched from inception to December 2017. The primary outcome of the meta-analysis was short-term or long-term AF recurrence following a single ablation procedure with or without the use of steroids. Both fixed- and random-effects models were used to calculate the overall effect estimates. Eight studies (four RCTs and four observational studies), with a total 992 patients, were included in the present study. Our meta-analysis shows that steroid use was associated with reduced AF occurrence at 3 months (odd ratio (OR) = 0.53, 95% confidence interval (CI) = 0.31-0.90, P=0.02) and 12-14 months (OR = 0.67, 95% CI = 0.47-0.95, P=0.02) after radiofrequency (RF) catheter ablation (RFCA). No clear benefit was observed for AF recurrence at 2-3 days, 1 or 24 months of follow-up. Steroid use was associated with decreased risk of early AF recurrence 3 and 12-14 months after ablation. No clear relationship was observed for 2-3 days, 1 and 24 months of follow-up and further data are needed to clarify these results.

Anticancer Therapy-Induced Atrial Fibrillation: Electrophysiology and Related Mechanisms

Some well-established immunotherapy, radiotherapy, postoperation, anticancer drugs such as anthracyclines, antimetabolites, human epidermal growth factor receptor 2 blockers, tyrosine kinase inhibitors, alkylating agents, checkpoint inhibitors, and angiogenesis inhibitors, are significantly linked to cardiotoxicity. Cardiotoxicity is a common complication of several cancer treatments. Some studies observed complications of cardiac arrhythmia associated with the treatment of cancer, including atrial fibrillation (AF), supraventricular arrhythmias, and cardiac repolarization abnormalities. AF increases the risk of cardiovascular morbidity and mortality; it is associated with an almost doubled risk of mortality and a nearly 5-fold increase in the risk of stroke. The occurrence of AF is also usually researched in patients with advanced cancer and those undergoing active cancer treatments. During cancer treatments, the incidence rate of AF affects the prognosis of tumor treatment and challenges the treatment strategy. The present article is mainly focused on the cardiotoxicity of cancer treatments. In our review, we discuss these anticancer therapies and how they induce AF and consequently provide information on the precaution of AF during cancer treatment.

Ankylosing spondylitis: A novel risk factor for atrial fibrillation - A nationwide population-based study

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease, associated with a number of cardiovascular diseases. We sought to investigate whether AS increases the risk of atrial fibrillation (AF) in a nationwide population-based study.

METHODS

A total of 14,129 patients newly diagnosed with AS (mean age 41.8 ± 15.3 years, 72% male) were recruited from the Korean National Health Insurance Service database between 2010 and 2014 and followed up for new onset AF. Age- and sex-matched non-AS subjects (1:5, n = 70,645) were selected and compared with the AS patients.

RESULTS

During a mean follow-up of 3.5 years, AF was newly diagnosed in 486 patients (114 patients of the AS group). The AS patients developed AF more frequently than the non-AS subjects (2.32 vs. 1.51 per 1000 person-years). In multivariate Cox regression analysis, AS was an independent risk factor for AF (Hazard ratio [HR] 1.28, 95% confidence interval [1.03-1.58]). The AS with tumor necrosis factor inhibitor (TNFi) therapy group showed higher risk for AF (HR 1.60 [1.02-2.39]). In younger patients of the AS group (patients <40 years old), the risk for AF was three times higher than patients at same age in the non-AS group. AS was an independent risk factor for AF in men, but not in women (HR 1.53 [1.18-1.95]; HR 1.42 [0.94-2.08], respectively).

CONCLUSIONS

AS was an independent risk factor for AF, especially in those under 40 years of age and those administered TNFi. It would be reasonable to screen for AF and stroke prevention in these high-risk patients.

Taurine Reverses Atrial Structural Remodeling in Ach-Cacl2 Induced Atrial Fibrillation Rats

Taurine has been reported to have anti-arrhythmia effects, but the anti-atrial fibrillation (AF) effects and its mechanism remain incompletely understood. In the present study, the therapy effects and partly mechanisms were investigated. AF animal model was established by intravenous administered with the mixture of acetylcholine (Ach) and CaCl2 (66 μg/mL + 10 mg/mL) (i.v.) for 7 days. The actions of taurine (99 mg/kg∙d, introgastric administration) on the levels of Hs-CRP, IL-6, TNF-α, MMP-9, AngII, the extent of the fibrosis and ultrastructural changes in left atrial were studied. The data showed that the serum levels of TNF-α, IL-6, AngII and the plasma levels of Hs-CRP and MMP-9 were significantly elevated in automatic recovery group relative to the control group (p < 0.01), which were all decreased by taurine administration (p < 0.01) similar to Verapamil treatment. Masson's trichrome staining of the left atrial tissue showed an obvious interstitial fibrosis in rats of automatic recovery group. The alteration could be reversed by additional taurine. Electron microscopy revealed that taurine administration could significantly alleviate the ultrastructural damage of atrial cells, and the effects were similar to the Verapamil treatment. In conclusion, the results suggested that taurine could inhibit the structural remodeling of AF in rats partly by decreasing the levels of inflammatory factors and profibrotic molecules, attenuating the extent of myocardial fibrosis and protecting the integrity of myocardial ultrastructure.

Increased risk of atrial fibrillation in patients with benign prostatic hyperplasia: A population-based cohort study

OBJECTIVE

The objective was to compare the rate of onset of atrial fibrillation (AF) in patients with benign prostatic hyperplasia (BPH) as compared with controls.

METHODS

We performed a retrospective study on national health registry comparing the incidence of AF between a cohort of 15 670 BPH patients and a propensity-matched cohort of 15 670 control patients. Univariable and multivariable Cox proportional hazards models were performed to estimate the hazard ratios (HR) and 95% confidence intervals (CI) of incident AF associated with BPH. A subgroup analysis was performed to evaluate the risk of AF among BPH patients whether they received a BPH surgery or not as compared with those without BPH.

RESULTS

We found a 4.77 incidence rate per 1000 person-years in the BPH group, compared to 3.76 in the control group. After controlling for the confounders, a significant association between BPH and risk of incident AF was shown with an adjusted HR = 1.19, 95% CI = 1.11-1.28) and this association was attenuated once surgical intervention for BPH has been applied (adjusted HR = 0.86, 95% CI = 0.76-0.97).

CONCLUSIONS

This study supported the notion that BPH is associated with greater AF occurrence.

Premature atrial and ventricular complexes in outpatients referred from a primary care facility

Background

Premature complexes are common electrocardiographic findings in daily clinical practice that require further evaluation. Investigation may sometimes be complex and expensive. The aim of our study was to analyze variables associated with premature beats identified in outpatients referred from a primary care facility.

Materials and methods

We performed a cross-sectional study of 407 outpatients (aged 55.8±11years; 56% women) who were followed by general practitioners and were referred for resting 12-lead electrocardiograms for a routine clinical follow-up. After signing informed consent, patients answered a questionnaire and underwent physical examinations, laboratory diagnostics, transthoracic echocardiograms and 24-hour Holter monitoring to evaluate for the presence of premature complexes. After the univariate analyses, logistic regression analyses were performed with adjustment for age, sex, and cardiovascular diseases.

Results

Premature complexes distribution revealed that they were frequent but with low density. Premature atrial complexes (≥ 4/hours) were associated with age (Odds Ratio (OD) = 1.030, Confidence Interval (CI) 95% = 1.002 ─ 1.059, p = 0.029), brain natriuretic peptide (BNP) levels > 20mg/dL (OR = 4.489, 95%CI = 1.918 ─ 10.507, p = 0.0005), intraventricular blocks (OR = 4.184, 95%CI = 1.816 ─ 9.406, p = 0.0005) and left atrial diameter (OR = 1.065, 95%CI = 1.001 ─ 1.134, p = 0.046). Premature ventricular complexes (≥ 5/hour) were related to age (OR = 1.032, 95%CI = 1.010 ─ 1.054, p = 0.004), the use of calcium channel blockers (OR = 2.248, 95%CI = 1.019 ─ 4.954, p = 0.045), HDL-cholesterol levels (OR = 0.971, 95%CI = 0.951 ─ 0.992, p = 0.007), BNP levels > 20mg/dL (OR = 2.079, 95%CI = 0.991 ─ 0.998, p = 0.033), heart rate (OR = 1.019, 95%CI = 1.001 ─ 1.038, p = 0.041), left ventricular hypertrophy (OR = 2.292, 95%CI = 1.402 ─ 3.746, p = 0.001) and left ventricular ejection fraction (OR = 0.938, 95%CI = 0.900 ─ 0.978, p = 0.002).

Conclusions

Premature complexes had low density and were associated with BNP levels > 20mg/dL, lower levels of HDL-cholesterol, left atrial enlargement and ventricular hypertrophy. The identification of premature complexes on 24-hour Holter monitor recordings of outpatients in a primary public healthcare setting was associated with uncontrolled cardiovascular risk factors that may be addressed with medical advice and therapy in a primary care setting.

Biomarkers and arrhythmia recurrence following radiofrequency ablation of atrial fibrillation

Objective

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and radiofrequency catheter ablation of AF (RCAAF) has become increasingly popular. Cardiac stress and inflammation have been associated with AF. This study was performed to determine whether the pre- or post-AF ablation levels of high-sensitivity C-reactive protein (hs-CRP) and N-terminal pro–B-type natriuretic peptide (NT-proBNP) are predictive of AF recurrence.

Methods

This multicenter prospective cohort study involved patients undergoing RCAAF in Switzerland and Canada. The primary endpoint was the recurrence of AF or atrial flutter at 6 months.

Results

Of 202 patients, 195 completed follow-up (age, 57.5 ± 9 years; mean left ventricular ejection fraction, 62%; mean left atrial size, 19.4 cm²). Patients with AF recurrence had larger atrial surfaces and longer total RCAAF times. Both the pre-ablation hs-CRP level and 1-day post-RCAAF NT-proBNP level were significantly associated with an increased risk of recurrence.

Conclusions

The pre-ablation hs-CRP level and immediate post-ablation NT-proBNP level were markers for atrial arrhythmia recurrence after RCAAF. This confirms growing evidence of the role of inflammation in the pathogenesis of AF. These biomarkers appear to be promising stratification tools for selection and management of patients undergoing RCAAF.

Risk of thromboembolism in patients developing critical illness-associated atrial fibrillation

Although common, the long-term significance of -developing atrial fibrillation (AF) during a period of critical illness is unclear. We undertook a retrospective cohort analysis to -assess the rate of thromboembolism (TE) in patients -developing atrial fibrillation de novo during admission to our intensive care unit. In total, 1,955 patients were followed up (-maximum follow-up 1,276 days) for the occurrence of TE, of which 220 (11.3%) had developed AF or atrial flutter during their critical care admission. There were 11 TE events among the patients with new AF (0.053 events per patient-year), compared with 18 in the non-AF group (0.0059 events per patient-year). The unadjusted hazard ratio for TE in patients developing new AF compared with those not developing AF was 8.09 (95% CI 3.08-17.19, p<0.001). In patients admitted to critical care, the development of AF appears to be associated with a significantly increased risk of subsequent thromboembolism.

[New onset atrial fibrillation in patients with sepsis]

BACKGROUND

Atrial fibrillation is the most common new onset arrhythmia in patients hospitalized with sepsis; however, there are no specific treatment guidelines and the ideal therapeutic approaches still remain unclear.

OBJECTIVES

To begin with the current state of knowledge concerning the underling mechanisms, the incidence and prognostic impact of new onset atrial fibrillation during sepsis are presented. Then a possible therapeutic algorithm for the special situation of sepsis is derived with respect to the currently existing atrial fibrillation guidelines. Finally necessary future research topics are outlined.

MATERIAL ANS METHODS

A systematic literature search was conducted in MEDLINE. All publications (reviews and studies) relevant for the summary of the current knowledge regarding new onset atrial fibrillation in septic patients were included.

RESULTS

The underlying patchomechanism is primarily systemic inflammation. Approximately 8% of patients with sepsis and more than 20% of patients with septic shock develop new onset atrial fibrillation. The occurrence of atrial fibrillation is associated with increased morbidity and mortality. The necessity of rhythm control therapy is dependent on the hemodynamic stability. The success rate of electrical cardioversion can be increased by the administration of amiodarone. The necessity of systemic anticoagulation is based on the individual risk of thromboembolism.

CONCLUSION

Further research is needed to unveil the optimal therapeutic strategies for patients with new onset atrial fibrillation during sepsis.

Sick sinus syndrome associated with anti-programmed cell death-1

Background

Use of anti-programmed cell death-1 (anti-PD-1) has been successful in treating many types of cancers. Despite its promising efficacy, immune-related adverse events are still a major concern. Immune-related cardiotoxicity, which is rare but fatal, has recently become a focus of attention. Cardiotoxicities including myocarditis, cardiomyopathy, cardiac fibrosis, heart block and cardiac arrest have been reported. Of these toxicities, myocarditis is often accompanied by dysrhythmia. The presentation of sick sinus syndrome as an immune-related adverse event has not yet been reported. Here, we reported the first case of sick sinus syndrome, a rare toxicity induced by anti-PD-1.

Case presentation

A 42-year-old male patient who had metastatic hepatocellular carcinoma failed treatment with sorafenib. Pembrolizumab at a fixed dose of 100 mg every three weeks was given. His heart rate gradually slowed down and he presented sick sinus syndrome with a lowest heart rate of 38 bpm after six cycles of pembrolizumab. He denied chest tightness, cold sweating, palpitation and dyspnea. Lab data including cardiac enzyme, electrolytes and thyroid function were all within a normal range. Simultaneously, he complained of fatigue, dizziness and anorexia with hypotension. Lab data revealed low cortisol and ACTH levels. Anti-PD-1 induced adrenal insufficiency was suspected. Low-dose cortisone (12.5 mg) was prescribed, and the patient’s symptoms, hypotension and sick sinus syndrome showed rapid improvement. Cortisone was gradually titrated and discontinued three weeks later. His sick sinus syndrome did not relapse and the cortisol and ACTH level returned to normal.

Conclusions

Sick sinus syndrome caused by anti-PD-1 treatment is a rare adverse event. With the development of sick sinus syndrome, myocarditis should be the first differential diagnosis because of its lethality. From this case, we learned that sick sinus syndrome may be a presentation of immune- or adrenal insufficiency-mediated sinus node dysfunction, both could be reversed with a glucocorticoid supplement.

Atrial Fibrillation, Cognitive Decline, and Dementia: an Epidemiologic Review

PURPOSE OF REVIEW

Atrial fibrillation (AF) and dementia are both prevalent diseases in aging societies, which exert a great economic burden worldwide. Although a handful of epidemiologic studies have indicated that AF is independently associated with faster cognitive decline and a higher risk of dementia, there is still a lack of comprehensive understanding of the observed association. In this review, we summarize evidence from major epidemiologic studies concerning AF-related cognitive decline and dementia, the potential mechanisms underlying their association, and the cognitive benefits of treatment options.

RECENT FINDINGS

A large majority of population-based longitudinal studies have consistently shown an independent association of AF with cognitive decline and dementia with varying effect sizes, depending on the age of the study population and the presence of clinical stroke. The underlying pathways linking AF to cognitive phenotypes may involve systemic inflammation, cerebral hypoperfusion, and cerebral small vessel disease and microemboli. However, current evidence is insufficient to support the potential benefits of AF treatment in reducing risk of cognitive decline and dementia.

SUMMARY

Current epidemiologic research suggests that AF contributes to cognitive decline and dementia, independent of a history of stroke. Further work is warranted to elucidate the potential mechanisms underlying this association, and more well-designed studies are needed to explore the possible cognitive benefits of different therapeutic options in patients with AF.

The presence of atrial fibrillation in Takotsubo cardiomyopathy is predictive of mortality: Systematic review and meta-analysis

INTRODUCTION

Atrial fibrillation (AF) is known as the most common arrhythmia and an independent risk factor for mortality. Recent studies suggest that AF is associated with morbidity and mortality in Takotsubo cardiomyopathy (TTC). However, a systematic review and meta-analysis of the literature have not been done. We assessed the association between AF in patients with TTC and mortality by a systematic review of the literature and a meta-analysis.

METHODS

We comprehensively searched the databases of MEDLINE and EMBASE from inception to January 2018. Included studies were published prospective or retrospective cohort studies that compared all-cause mortality in TTC with AF versus without AF. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate risk ratios and 95% confidence intervals.

RESULTS

Five studies from August 2008 to October 2017 were included in this meta-analysis involving 2,321 subjects with TTC (243 with AF and 2,078 without AF). The presence of AF was associated with all-cause mortality (pooled odds ratio = 2.19, 95% confidence interval: 1.57-3.06, p < 0.001, I ²  = 0%).

CONCLUSION

Atrial fibrillation increased all-cause mortality by double among patients with TTC compared to without it. Our study suggests that the presence of AF in TTC is prognostic for all-cause mortality.

[Biomarkers and atrial fibrillation : Prediction of recurrences and thromboembolic events after rhythm control management]

Atrial fibrillation (AF) is the most common arrhythmia in clinical praxis and is associated with an increased risk for cardio- and cerebrovascular complications leading to an increased mortality. Catheter ablation represents one of the most important and efficient therapy strategies in AF patients. Nevertheless, the high incidence of arrhythmia recurrences after catheter ablation leads to repeated procedures and higher treatment costs. Recently, several scores had been developed to predict rhythm outcomes after catheter ablation. Biomarker research is also of enormous interest. There are many clinical and blood biomarkers pathophysiologically associated with AF occurrence, progression and recurrences. These biomarkers-including different markers in blood (e. g. von Willebrand factor, D‑dimer, natriuretic peptides) or urine (proteins, epidermal grown factor receptor) but also cardiac imaging (echocardiography, computed tomography, magnetic resonance imaging)-could help to improve clinical scores and be useful for individualized AF management and optimized patients' selection for different AF treatment strategies. In this review, the role of diverse biomarkers and their predictive value related to AF-associated complications are discussed.

Impact of periodontitis as representative of chronic inflammation on long-term clinical outcomes in patients with atrial fibrillation

Objectives

Relationship between atrial fibrillation (AF) and inflammation was shown in previous studies. However, there was limited data about the association between the periodontitis and AF in the long-term follow-up. The aim of this study was to evaluate the impact of periodontitis on long-term clinical outcomes in patients with AF.

Methods

The Kosin University echocardiography, ECG and periodontitis database were reviewed from 2013 to 2015 to identify patients with AF. Those patients were divided into two groups according to the presence of periodontitis and clinical events including any arrhythmic attack, thromboembolic and bleeding and death were collected during a median of 18 months.

Results

Among 227 patients with AF, 47 (20.7%) patients had periodontitis. Major adverse cardiac events (MACE) were significantly higher in patients with periodontitis compared with those without periodontitis (p<0.001). Arrhythmias including AF, atrial tachycardia, atrial premature beat, ventricular tachycardia and ventricular premature beat also occurred in 44 (93.6%) patients, which was higher significantly higher incidence in patients with periodontitis than in those without periodontitis (p<0.001). In univariate analysis, age, CHA₂DS₂-VASc, left atrial volume index (LAVi) and periodontitis were significantly associated with arrhythmic events and MACE including bleeding events, thromboembolic events, arrhythmic events and mortality. In multivariate analysis, LAVi (p=0.005) and periodontitis (p<0.001) were independent risk factors for arrhythmic events and periodontitis (p<0.001) for MACE at the long-term follow-up.

Conclusions

The periodontitis as representative of chronic inflammation was an independent predictor of arrhythmic events and MACE in patients with AF.

Aplastic Anemia and Risk of Incident Atrial Fibrillation - A Nationwide Cohort Study

BACKGROUND

This retrospective cohort study sought to follow up patients with aplastic anemia (AA) to evaluate their risk of developing atrial fibrillation (AF).

METHODS AND RESULTS

From the National Health Insurance Research Database of Taiwan, this study identified an AA cohort (n=3,921), a general population cohort (n=17,617,843) and a propensity score-matched none AA cohort (PSM non-AA cohort in brief, n=15,684) in 2000-2010. By the end of 2011, the incident AF was higher in the AA cohort than in the general population and PSM non-AA cohorts (8.94 vs. 1.14 and 6.47 per 1,000 person-years, respectively). The adjusted hazards ratio of AF for the AA cohort was 2.12 (95% confidence interval 1.46-3.08) compared with the PSM non-AA cohort, after controlling for covariates. However, after further controlling for the competing risk of death, adjusted subhazard ratio was 1.21 (95% CI 0.97-1.50). Among those who developed AF, the AA cohort had a higher mortality rate (83.7 vs. 51.1 per 100), but a lower rate of incident stroke (26.0 vs. 41.5 per 100), compared with the PSM non-AA cohort.

CONCLUSIONS

Patients with AA could have an elevated risk for AF. The mortality risk increased further for those who develop AF.

Predictors of acute myocarditis in complicated scrub typhus: an endemic province in the Republic of Korea

BACKGROUND/AIMS

Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus.

METHODS

We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn't have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis.

RESULTS

Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001).

CONCLUSIONS

Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed.

Low-dose green tea intake reduces incidence of atrial fibrillation in a Chinese population

The aim of the present study was to assessthe association between green tea intake and incidence of atrial fibrillation (AF) in a Chinese population. A total of 801 (mean age: 62 years; 56% male) subjects were enrolled: 401 AF patients and 400 controls. All subjects completed a questionnaire and the associations between their green tea drinking habits and incidence of AF were assessed using the odds ratio (OR) and binary logistic regression. After multivariate adjustment, green tea intake presented as a protective factor against the incidence of AF (OR: 0.349, 95% CI: 0.253-0.483, P < 0.001). The green tea protection showed downward trend with increasing green tea intake (P for the trend= 0.001). Low frequency, low concentration, short-term tea consumption was classified as low-dose green tea intake. Green tea intake decreased the incidence of both paroxysmal AF (OR: 0.307, 95% CI: 0.216-0.436, P < 0.001) and persistent AF (OR: 0.355, 95% CI: 0.261-0.482, P < 0.001) and may be associated with a decreased incidence of AF. This study suggests that low-dose green tea intake strongly protects against AF.

Prognostic role of MIR146A polymorphisms for cardiovascular events in atrial fibrillation

There are few biomarkers able to forecast new thrombotic events in patients with AF. In this framework, microRNAs have emerged as critical players in cardiovascular biology. In particular, miR-146a-5p is recognised as an important negative regulator of inflammation. This study aims to evaluate the prognostic role and biological effect of functional MIR146A polymorphisms, rs2431697 and rs2910164, in non-valvular atrial fibrillation (AF) patients under oral anticoagulation. We studied 901 patients with permanent/paroxysmal AF stabilized for at least six months. Patients were followed-up for two years and adverse cardiovascular events (ACE) were recorded. In vitro studies were performed in monocytes from healthy homozygous for the two genotypes of rs2431697. Rs2910164 had no association with ACE. However, multivariate analysis (adjusted by CHA2DS2–VASc score) revealed that rs2431697TT was associated with adverse cardiovascular events [HR: 1.64 (1.09–2.47); p=0.017]. The predictive value of usefulness of the CHA2DS2–VASc+IL6+rs2431697 for predicting ACE, was statistically better than that predicted by CHA2DS2–VASc+IL6. Functional studies showed that after 24 hours incubation, monocytes from CC individuals showed a 65 % increase in miR-146a-5p levels, while TT individuals only showed a 28 % increase. Indeed, after 24 hours of LPS activation, TT monocytes showed a higher increase in IL6 mRNA expression than CC (52 % vs 26 %). Our study established MIR146A rs2431697 as a prognostic biomarker for ACE in anticoagulated AF patients. These data suggest that TT individuals, when submitted to an inflammatory stress, may be prone to a highest pro-inflammatory state due, in part, to lower levels of miR-146a-5p.

Influenza vaccination might reduce the risk of ischemic stroke in patients with atrial fibrillation: A population-based cohort study

Purpose

Atrial fibrillation (AF) is associated with the risk of ischemic stroke, regardless of the administration of appropriate antithrombotic prophylaxis. This study investigated whether influenza vaccination is associated with the risk of ischemic stroke, to determine a solution to reduce this risk in patients with AF.

Methods

We used data from the Taiwan National Health Insurance Research Database. The study cohort comprised all patients diagnosed as having AF (n = 14 454) before January 1, 2005; these patients were followed until December 31, 2012. The index date was January 1, 2005. A propensity score was derived using a logistic regression model to estimate the effect of vaccination by accounting for covariates that predict receiving the intervention (vaccine). A Cox proportional hazard model was used to calculate the hazard ratios (HRs) of ischemic stroke in vaccinated and unvaccinated patients with AF.

Results

We included 6570 patients (2547 [38.77%] with and 4023 [61.23%] without influenza vaccination). The adjusted HRs (aHRs) of ischemic stroke were lower in the vaccinated patients than in the unvaccinated patients (influenza season, noninfluenza season, and all seasons: aHRs = 0.59, 0.50, and 0.55; P < 0.001, P < 0.001, and P < 0.001, respectively).

Conclusions

Influenza vaccination might exert a dose-response effect against ischemic stroke in patients with AF who have risk factors for ischemic stroke by reducing the incidence of ischemic stroke, particularly in those aged 65–74 and ≥75 y.

Systemic effects in naïve mice injected with immunomodulatory lectin ArtinM

Toll-like receptors (TLR) contain N-glycans, which are important glycotargets for plant lectins, to induce immunomodulation. The lectin ArtinM obtained from Artocarpus heterophyllus interacts with TLR2 N-glycans to stimulate IL-12 production by antigen-presenting cells and to drive the immune response toward the Th1 axis, conferring resistance against intracellular pathogens. This immunomodulatory effect was demonstrated by subcutaneously injecting (s.c.) ArtinM (0.5 μg) in infected mice. In this study, we evaluated the systemic implications of ArtinM administration in naïve BALB/c mice. The mice were s.c. injected twice (7 days interval) with ArtinM (0.5, 1.0, 2.5, or 5.0 μg), LPS (positive control), or PBS (negative control) and euthanized after three days. None of the ArtinM-injected mice exhibited change in body weight, whereas the relative mass of the heart and lungs diminished in mice injected with the highest ArtinM dose (5.0 μg). Few and discrete inflammatory foci were detected in the heart, lung, and liver of mice receiving ArtinM at doses ≥2.5 μg. Moreover, the highest dose of ArtinM was associated with increased serum levels of creatine kinase MB isoenzyme (CK-MB) and globulins as well as an augmented presence of neutrophils in the heart and lung. IL-12, IFN-γ, TNF-α, and IL-10 measurements in the liver, kidney, spleen, heart, and lung homogenates revealed decreased IL-10 level in the heart and lung of mice injected with 5.0 μg ArtinM. We also found an augmented frequency of T helper and B cells in the spleen of all ArtinM-injected naïve mice, whereas the relative expressions of T-bet, GATA-3, and ROR-γt were similar to those in PBS-injected animals. Our study demonstrates that s.c. injection of high doses of ArtinM in naïve mice promotes mild inflammatory lesions and that a low immunomodulatory dose is innocuous to naïve mice.

Effect of atrial fibrillation duration on plasma von Willebrand factor level

AIMS

von Willebrand factor (VWF) is an independent risk factor for adverse events in patients with non-valvular atrial fibrillation (NVAF). However, it is unclear if VWF level remains elevated and predictive of stroke during entire course of NVAF.

METHODS AND RESULTS

In order to determine if VWF is a time-dependent blood variable, VWF antigen measured by latex immunoassay in 425 NVAF patients and 100 controls with normal sinus rhythm (NSR) was analyzed according to NVAF duration (<1 month: n = 76, 1-12 months: n = 98, and >12 months: n = 251). The mean VWF antigen level in NVAF patients with <1-month duration (167 ± 59%) was not different compared to those with 1-12 months (157 ± 50%, P = .24) and >12 months duration (156 ± 54%, P = .11) but higher compared to NSR controls (143 ± 48%, P = .003). Higher VWF level correlated with higher CHADS₂ scores and with progressing intensity of blood stasis in the left atrium and thrombus formation in all three time periods of atrial fibrillation duration. Patients not treated with warfarin had VWF 30% higher in the first month compared to following months.

CONCLUSIONS

von Willebrand Factor is steadily elevated throughout the course of dysrhythmia in NVAF patients treated with warfarin and in those with higher intensity of left atrium blood stasis.

Evolutional change in epicardial fat and its correlation with myocardial diffuse fibrosis in heart failure patients

OBJECTIVES

The aim of this study was to characterize the characteristics of epicardial fat (EAT) in different stage heart failure (HF) patients and its relationship between cardiac fibrosis.

BACKGROUND

EAT is visceral adipose tissue that possesses inflammatory properties. Inflammation and obesity are associated with cardiac fibrosis, but the relationship between cardiac fibrosis and EAT is unknown.

METHODS

EAT volume was measured using cardiac magnetic resonance imaging (CMR) in 180 subjects: 58 patients with systolic HF, 63 patients with HF and preserved ejection fraction, and 59 patients without HF. CMR derived myocardial extracellular volume (ECV) was used for fibrosis quantification.

RESULTS

Patients with systolic HF had significantly more EAT compared with patients with HF and preserved ejection fraction or the control group (patients without HF) (indexed EAT volume [mL/m²], 27.0 [22.7-31.6] vs 25.6 [21.4-31.2] and 24.2 [21.0-27.6], P < .05). The adjusted EAT amount was associated with ECV completely independent of age, hypertension, diabetes, etiology of HF, left ventricular ejection fraction, CMR-late gadolinium enhancement (LGE), left ventricular mass index, and left ventricular end-diastolic volume index (correlation coefficient: 0.49; 95% confidence interval: 0.12-0.86, P < .01). Increased CMR ECV was more associated with EAT in those with advanced age, male sex, LGE on magnetic resonance imaging-LGE images, and less left ventricular end-diastolic volume index.

CONCLUSIONS

EAT volume is highly associated with CMR ECV independent of traditional risk factors and left ventricular mass or volume. Whether EAT plays a role in the long-term prognosis of HF requires future investigation.

Discordant Relationships between Systemic Inflammatory Markers and Burden of Oxidative Stress in Patients with Atrial Fibrillation

BACKGROUND AND OBJECTIVES

Oxidative stress (OS) plays an important role in the pathophysiology of atrial fibrillation (AF) by amplifying the inflammatory cascade, wherein augmented inflammation facilitates the atrial electrical remodeling process. Few studies have investigated the possible link between systemic inflammation and OS in AF.

SUBJECTS AND METHODS

A total of 220 consecutive patients with AF (117 patients) or healthy controls (103 patients) were enrolled. Among the 117 AF patients, 65 paroxysmal AF (PaAF) and 52 persistent AF (PeAF) patients were included. The level of 8-iso-prostaglandin F2α (8-iso-PGF2α) was measured as a marker of OS burden. We evaluated the correlations between 3 systemic inflammatory markers, high-sensitivity C-reactive protein (hsCRP), neutrophil to lymphocyte ratio (NLR), and red cell distribution width (RDW), and 8-iso-PGF2α.

RESULTS

The 8-iso-PGF2α concentration in both PaAF and PeAF patients was higher than that of controls (p<0.001 and p=0.024, respectively). The NLR and RDW of PeAF patients were higher than those of both control and PaAF patients (p=0.041 and p=0.031 for NLR, p=0.057 and p=0.031 for RDW, respectively). There were no correlations between specific inflammatory markers and the 8-iso-PGF2α in AF. The 8-iso-PGF2α level decreased gradually with an increase in AF duration (p=0.008), contrary to the graded increase in hsCRP. Multiple regression analysis indicated that AF duration persisted as a significant determinant of 8-iso-PGF2α (β=-0.249, p=0.044).

CONCLUSION

Systemic inflammatory marker levels were not proportional to the levels of 8-iso-PGF2α, an OS marker, in AF.