The preventive effect of atorvastatin on atrial fibrillation: a meta-analysis of randomized controlled trials

Isolated coronary artery bypass grafting in septuagenarians

As life expectancy increases, the number of elderly patients with coronary artery disease requiring coronary artery bypass grafting (CABG) also increases. This study aims to analyse the outcomes of isolated CABG in septuagenarians. Isolated CABG patients between 70 and 79 years from January 1, 2017, to December 31, 2022, were included. Clinical data were obtained from medical records and through a phone call. Out of 618 isolated CABG patients, 132 (21.35%) were septuagenerians. Off-pump and on-pump beating heart CABG was performed in 123 (93.18%) and 9 (6.81%), respectively. Emergency CABG was performed in two patients (1.51%). The mean expected EuroSCORE II (European System for Cardiac Operative Risk evaluation) operative mortality was 2.51%. The incidence of in-hospital mortality, stroke and atrial fibrillation was 1.5%, 0.85% and 6.06%, respectively. An intra-aortic balloon pump was used in six patients (4.5%). The actuarial survival at 1 year, 5 years and 6 years were 98.1 ± 1.4%, 85.5 ± 4.7% and 85.5 ± 4.7%, respectively. The average duration of ventilation, intensive care unit (ICU) and hospital stay were 14.18 ± 10.37 h, 2.48 ± 0.89 days and 6.07 ± 1.8 days, respectively. EuroSCORE-II grading was associated with major adverse cardiovascular events. We conclude that performing CABG on septuagenarians in Indian population is safe.

Pathophysiology and clinical relevance of atrial myopathy

Atrial myopathy is a condition that consists of electrical, structural, contractile, and autonomic remodeling of the atria and is the substrate for development of atrial fibrillation, the most common arrhythmia. Pathophysiologic mechanisms driving atrial myopathy are inflammation, oxidative stress, atrial stretch, and neurohormonal signals, e.g., angiotensin-II and aldosterone. These mechanisms initiate the structural and functional remodeling of the atrial myocardium. Novel therapeutic strategies are being developed that target the pathophysiologic mechanisms of atrial myopathy. In this review, we will discuss the pathophysiology of atrial myopathy, as well as diagnostic and therapeutic strategies.

Statin versus ezetimibe-statin for incident atrial fibrillation among patients with type 2 diabetes mellitus with acute coronary syndrome and acute ischemic stroke

The objective was to assess the role of the combination approach with ezetimibe 10 mg/simvastatin 20 mg versus atorvastatin 40 mg in predicting atrial fibrillation (AF) in type 2 diabetes mellitus patients with acute coronary syndrome and acute ischemic stroke. The authors formed a cohort of diabetic patients with extensive vascular diseases between 2000 and 2018 using data from the National Health Insurance Research Database in Taiwan. AF was the outcome of interest in this study. Cox proportional hazards regression analysis was performed to estimate the hazard ratios and 95% confidence intervals in the analysis. After controlling for sex, age, comorbidities and medications, the patients coexisting with type 2 diabetes mellitus, acute coronary syndrome and acute ischemic stroke with ezetimibe 10 mg/simvastatin 20 mg treatment were not significantly at risk of AF, compared to the patients with atorvastatin 40 mg treatment (adjusted hazard ratio, 0.85; 95% confidence interval, 0.52-1.38). A similar effect for AF risk between ezetimibe 10 mg/simvastatin 20 mg and atorvastatin 40 mg users was observed in the current investigation.

Comparison of the Efficacy of Atorvastatin and Rosuvastatin in Preventing Atrial Fibrillation after Coronary Artery Bypass Grafting: A Double-Blind Randomized Comparative Trial

Background

Atrial fibrillation (AF) is a supraventricular tachyarrhythmia characterized by disorganized atrial activity and subsequent mechanical atrial failure. Postoperative AF is a frequent complication of coronary artery bypass grafting (CABG). Although there is evidence of decreased AF after CABG with statin usage, information is scarce regarding a direct comparison between atorvastatin and rosuvastatin. The present study was conducted to compare the efficacy of rosuvastatin and atorvastatin in preventing post-CABG AF.

Methods

The present double-blind randomized comparative clinical trial selected CABG candidates with stable ischemic heart disease or acute coronary syndromes. Atorvastatin (40 mg per day) or rosuvastatin (20 mg per day) was prescribed 1 week before surgery, and the outcomes were compared.

Results

Two-hundred patients, 100 cases in each group, completed the study. Twenty-five patients in each group were female, and the mean age was 59.30±8.42 years in the rosuvastatin group and 60.13±9.40 years in the atorvastatin group (P=0.513). The frequency of AF was 31% in the atorvastatin group and 27% in the rosuvastatin group (P=0.534). No significant differences existed between the groups concerning the length of hospital and ICU stay (P=0.333 and P=0.161) and in-hospital and 3-month mortality (P=0.315 and P=0.648). A subgroup analysis of only patients with stable ischemic heart disease could not detect a significant difference between the study groups in any of the investigated outcomes. Our logistic regression analysis showed an association only between age and the incidence of AF after CABG (OR, 1.12; 95% CI, 1.05 to 1.20; P<0.01).

Conclusion

Rosuvastatin and atorvastatin are similar concerning the prevention of post-CABG AF, but there is a need for future well-designed multicenter studies on this topic.

The Atrium in Atrial Fibrillation - A Clinical Review on How to Manage Atrial Fibrotic Substrates

Atrial fibrillation (AF) is the most common sustained arrhythmia in the population and is associated with a significant clinical and economic burden. Rigorous assessment of the presence and degree of an atrial arrhythmic substrate is essential for determining treatment options, predicting long-term success after catheter ablation, and as a substrate critical in the pathophysiology of atrial thrombogenesis. Catheter ablation of AF has developed into an essential rhythm-control strategy. Nowadays is one of the most common cardiac ablation procedures performed worldwide, with its success inversely related to the extent of atrial structural disease. Although atrial substrate evaluation remains complex, several diagnostic resources allow for a more comprehensive assessment and quantification of the extent of left atrial structural remodeling and the presence of atrial fibrosis. In this review, we summarize the current knowledge on the pathophysiology, etiology, and electrophysiological aspects of atrial substrates promoting the development of AF. We also describe the risk factors for its development and how to diagnose its presence using imaging, electrocardiograms, and electroanatomic voltage mapping. Finally, we discuss recent data regarding fibrosis biomarkers that could help diagnose atrial fibrotic substrates.

The Increasing Role of Rhythm Control in Patients With Atrial Fibrillation: JACC State-of-the-Art Review

The considerable mortality and morbidity associated with atrial fibrillation (AF) pose a substantial burden on patients and health care services. Although the management of AF historically focused on decreasing AF recurrence, it evolved over time in favor of rate control. Recently, more emphasis has been placed on reducing adverse cardiovascular outcomes using rhythm control, generally by using safe and effective rhythm-control therapies (typically antiarrhythmic drugs and/or AF ablation). Evidence increasingly supports early rhythm control in patients with AF that has not become long-standing, but current clinical practice and guidelines do not yet fully reflect this change. Early rhythm control may effectively reduce irreversible atrial remodeling and prevent AF-related deaths, heart failure, and strokes in high-risk patients. It has the potential to halt progression and potentially save patients from years of symptomatic AF; therefore, it should be offered more widely.

Update on the efficacy of statins in primary and secondary prevention of atrial fibrillation

Atrial fibrillation is the most common arrhythmia in adults and its prevalence is growing rapidly. It has been shown that AF is associated with increased risk of heart failure, ischemic and hemorrhagic stroke, and mortality. Hence, there is growing interest among researchers in seeking preventive and therapeutic interventions regarding AF. In recent decades, it has been suggested that statins may decrease the incidence of AF and may also decrease its recurrence after cardioversion and catheter ablation. These effects are thought to be mediated by different mechanisms such as modulating inflammation, altering the properties of transmembrane ion channels, interfering with activation of matrix metalloproteinases, and acting on endothelial function. In this article, we review and update current knowledge about the role of statins in primary and secondary prevention of AF in general and specific populations.

Update on the efficacy of statins in primary and secondary prevention of atrial fibrillation

Atrial fibrillation is the most common arrhythmia in adults and its prevalence is growing rapidly. It has been shown that AF is associated with increased risk of heart failure, ischemic and hemorrhagic stroke, and mortality. Hence, there is growing interest among researchers in seeking preventive and therapeutic interventions regarding AF. In recent decades, it has been suggested that statins may decrease the incidence of AF and may also decrease its recurrence after cardioversion and catheter ablation. These effects are thought to be mediated by different mechanisms such as modulating inflammation, altering the properties of transmembrane ion channels, interfering with activation of matrix metalloproteinases, and acting on endothelial function. In this article, we review and update current knowledge about the role of statins in primary and secondary prevention of AF in general and specific populations.

Atrial fibrosis and substrate based characterization in atrial fibrillation: Time to move forwards

Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia in clinical practice. However, current therapeutic interventions for atrial fibrillation have limited clinical efficacy as a consequence of major knowledge gaps in the mechanisms sustaining atrial fibrillation. From a mechanistic perspective, there is increasing evidence that atrial fibrosis plays a central role in the maintenance and perpetuation of atrial fibrillation. Electrophysiologically, atrial fibrosis results in alterations in conduction velocity, cellular refractoriness, and produces conduction block promoting meandering, unstable wavelets and micro-reentrant circuits. Clinically, atrial fibrosis has also linked to poor clinical outcomes including AF-related thromboembolic complications and arrhythmia recurrences post catheter ablation. In this article, we review the pathophysiology behind the formation of fibrosis as AF progresses, the role of fibrosis in arrhythmogenesis, surrogate markers for detection of fibrosis using cardiac magnetic resonance imaging, echocardiography and electroanatomic mapping, along with their respective limitations. We then proceed to review the current evidence behind therapeutic interventions targeting atrial fibrosis, including drugs and substrate-based catheter ablation therapies followed by the potential future use of electro phenotyping for AF characterization to overcome the limitations of contemporary substrate-based methodologies.

Statin Therapy in Post-Operative Atrial Fibrillation: Focus on the Anti-Inflammatory Effects

BACKGROUND

Atrial fibrillation (AF) occurring after cardiac surgery, post-operative AF (POAF), is a serious and common complication of this treatment. POAF may be life-threatening and the available preventive strategies are insufficient or are associated with significantly increased risk of adverse effects, especially in long-term use. Therefore, more appropriate treatment strategies are needed.

METHODS

In this paper, the efficacy, safety, and other aspects of using statins in the prevention of POAF focusing on their anti-inflammatory effects are reviewed.

RESULTS

Recent studies have suggested that inflammation has a significant role in POAF, from the first AF episode to its serious complications including stroke and peripheral embolism. On the other hand, statins, the most widely used medications in cardiovascular patients, have pleiotropic effects, including anti-inflammatory properties. Therefore, they may potentially be effective in POAF prevention. Statins, especially atorvastatin, appear to be an effective option for primary prevention of POAF, especially in patients who had coronary artery bypass grafting (CABG), a cardiac surgery treatment associated with inflammation in the heart muscle. However, several large studies, particularly with rosuvastatin, did not confirm the beneficial effect of statins on POAF. One large clinical trial reported higher risk of acute kidney injury (AKI) following high-dose rosuvastatin in Chinese population. In this study, rosuvastatin reduced the level of C-reactive protein (CRP) but did not reduce the rate of POAF.

CONCLUSION

Further studies are required to find the most effective statin regimen for POAF prevention with the least safety concern and the highest health benefits.

The Efficacy of Anti-inflammatory Agents in the Prevention of Atrial Fibrillation Recurrences

Several studies have indicated an association between inflammation and the recurrence of Atrial Fibrillation (AF), especially after ablation, which is a therapeutic option leading to local inflammation. On the other hand, each AF can lead to another AF, as a general rule. Thus, preventing recurrences of AF is extremely important for patient outcomes. In this paper, we attempted to review the effect of medicinal agents with anti-inflammatory properties on the prevention of AF recurrence. There are several randomized controlled trials (RCTs) and meta-analyses on the prevention of AF recurrence using agents with anti-inflammatory properties, which include steroids, colchicine, statins, and n-3 fatty acids (n-3 FA). Clinical trials evaluating the efficacy of anti-inflammatory drugs in preventing the recurrence of AF led to inconsistent results for corticosteroids, statins and n-3 FAs. These results may be related to the fact that inflammation is not the only factor responsible for triggering recurrences of AF. For example, the presence of structural, mechanical and electrical remodeling could potentially be the most important factors that trigger recurrences of AF but these factors have not been addressed in most of the reported studies. Therefore, future clinical trials are needed to compare the efficacy of anti-inflammatory drugs in AF patients with, or without other factors. For colchicine, a potent anti-inflammatory drug, there are limited studies. However, all the studies investigating colchicine in the context of AF were consistent and promising, especially when colchicine was used on a short-term basis following ablation in patients with paroxysmal AF. Therefore, colchicine could be a promising candidate for further clinical studies involving recurrent AF.

Clinical factors related to successful or unsuccessful cardioversion in the EdoxabaN versus warfarin in subjectS UndeRgoing cardiovErsion of Atrial Fibrillation (ENSURE-AF) randomized trial

BACKGROUND

EdoxabaN versus warfarin in subjectS UndeRgoing cardiovErsion of Atrial Fibrillation evaluated use of nonvitamin K antagonist oral anticoagulant edoxaban vs enoxaparin-warfarin in patients with nonvalvular atrial fibrillation undergoing electrical cardioversion.

HYPOTHESIS

To assess clinical factors related to successful or unsuccessful cardioversion. To evaluate whether differences in adverse events based on anticoagulation strategy may exist.

METHODS

In this multicenter prospective randomized open-label blinded end-point evaluation trial, 2199 patients were randomized to edoxaban 60 mg once daily (30 mg for creatinine clearance 15-50 mL/min, weight ≤ 60 kg, and/or concomitant use of P-glycoprotein inhibitor) or enoxaparin-warfarin. Successful cardioversion was confirmed by 12-lead electrocardiography-documented sinus rhythm.

RESULTS

Cardioversion was successful in 1578 patients; in 355 patients, cardioversion was unsuccessful. Male, high body weight, high body mass index (BMI), coronary artery disease, concomitant aspirin, or prior statins use were more common in patients with unsuccessful cardioversion; international normalized ratio control did not differ by cardioversion success. On multivariate analysis, gender (P < .05), body weight (P = .0196) and BMI (P = .0377) emerged as independent predictors of successful cardioversion. There were no significant differences in primary efficacy (a composite of stroke, systemic embolic event, myocardial infarction, and cardiovascular death during overall study period) regardless of cardioversion success. There were no significant differences in bleeding rates, regardless of cardioversion outcome; notwithstanding low numbers, edoxaban and enoxaparin-warfarin did not differ.

CONCLUSIONS

Male gender, higher mean weight and higher mean BMI were associated with unsuccessful cardioversion. Efficacy and safety outcomes were low and did not differ by cardioversion success.

Effect of Postablation Statin Treatment on Arrhythmia Recurrence in Patients With Paroxysmal Atrial Fibrillation

BACKGROUND

Statins have been proposed as a means to prevent postablation atrial fibrillation (AF) recurrences, mainly on the basis of their pleiotropic effects. The objective of this subanalysis of a prospectively randomized controlled study population of patients undergoing radiofrequency ablation for paroxysmal AF was to test the hypothesis that statin treatment is associated with longer time to recurrence.

METHODS AND RESULTS

This is a subanalysis over an extended follow-up period of a prospective randomized study (ClinicalTrials.gov Identifier NCT01791699). Among 291 patients, 2 propensity score-matched subgroups of patients who received or did not receive statins after pulmonary vein isolation were created. In the unmatched cohort, there was no difference in the rate of recurrence between statin-treated and not treated patients, with a 1-year recurrence estimate of 19% and 23%, respectively (Gehan statistic 0.59, P = 0.443). In the propensity-matched cohort (N = 166, 83 per group), recurrence-free survival did not differ significantly between groups (839 days, 95% confidence interval 755-922 days, in the no statin group vs. 904 days, 95% confidence interval 826-983 in the statin group; P = 0.301). The 1-year recurrence rate estimate was 30% in the no statin group versus 27% in the statin group (Gehan statistic 0.56, P = 0.455).

CONCLUSION

Statin treatment does not seem to affect AF recurrence in following radiofrequency ablation for paroxysmal AF, over a follow-up time of about 2.5 years.

Data Linking Diabetes Mellitus and Atrial Fibrillation-How Strong Is the Evidence? From Epidemiology and Pathophysiology to Therapeutic Implications

According to estimates, around 5% of the world population has hazel eyes. And there are about as many people with diabetes mellitus (DM). Red hair occurs naturally in up to 2% of the human population. And about as many people are estimated to have atrial fibrillation (AF). If a hazel eyed person with red hair does not surprise us, should a diabetic patient with AF? Accumulating epidemiologic data suggest, however, that the DM-AF association may be more than a simple coincidence. But, how strong is this evidence? Experimental studies bring evidence for a DM-induced atrial proarrhythmic remodelling. But how relevant are these data for the clinical setting? In this review, we aim to provide a critical analysis of the existing clinical and experimental, epidemiologic, and mechanistic data that bridge DM and AF, we emphasize a number of questions that remain to be answered, and we identify hotspots for future research. The therapeutic implications of the DM-AF coexistence are also discussed, with a focus on rhythm control and on conventional and DM-specific upstream therapies for AF management.

Extending PubMed searches to ClinicalTrials.gov through a machine learning approach for systematic reviews

OBJECTIVES

Despite their essential role in collecting and organizing published medical literature, indexed search engines are unable to cover all relevant knowledge. Hence, current literature recommends the inclusion of clinical trial registries in systematic reviews (SRs). This study aims to provide an automated approach to extend a search on PubMed to the ClinicalTrials.gov database, relying on text mining and machine learning techniques.

STUDY DESIGN AND SETTING

The procedure starts from a literature search on PubMed. Next, it considers the training of a classifier that can identify documents with a comparable word characterization in the ClinicalTrials.gov clinical trial repository. Fourteen SRs, covering a broad range of health conditions, are used as case studies for external validation. A cross-validated support-vector machine (SVM) model was used as the classifier.

RESULTS

The sensitivity was 100% in all SRs except one (87.5%), and the specificity ranged from 97.2% to 99.9%. The ability of the instrument to distinguish on-topic from off-topic articles ranged from an area under the receiver operator characteristic curve of 93.4% to 99.9%.

CONCLUSION

The proposed machine learning instrument has the potential to help researchers identify relevant studies in the SR process by reducing workload, without losing sensitivity and at a small price in terms of specificity.

Relation Between Lipid Profile and New-Onset Atrial Fibrillation in Patients With Systemic Hypertension (From the Swedish Primary Care Cardiovascular Database [SPCCD])

The relation between dyslipidemia and atrial fibrillation (AF) development is still controversial. To assess the impact of lipid profile on new-onset AF, we followed 51,020 primary-care hypertensive patients without AF at baseline. After a mean follow-up time of 3.5 years, AF occurred in 2,389 participants (4.7%). We evaluated the association between total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and new-onset AF. In a Poisson regression model fully adjusted for common risk factors of AF, we found that 1.0 mmol/l (39 mg/dl) increase in total cholesterol was associated with 19% lower risk of new-onset AF (95% confidence interval [CI] 9% to 28%), and 1.0 mmol/l (39 mg/dl) increase in low-density lipoprotein cholesterol was associated with 16% lower risk of new-onset AF (95% CI 3% to 27%). Gender-specific Poisson regression analyses revealed that increase in total cholesterol by 1.0 mmol/l (39 mg/dl) was found to be associated with lower risk of new-onset AF with 21% in men (95% CI 8% to 32%), and 18% in women (95% CI 1% to 31%). There was no association between high-density lipoprotein cholesterol or triglycerides and new-onset AF, neither in the whole population with respect to separate gender. In conclusion, in a large hypertensive population we found an inverse association between total cholesterol and new-onset AF for both men and women. Our results confirm previous reports of a dyslipidemia paradox, and extend these observations to the hypertensive population.

Involvement of IL-1β and IL-6 in antiarrhythmic properties of atorvastatin in ouabain-induced arrhythmia in rats

PURPOSE

Evidence show that statins possess wide beneficial cardioprotective and anti-inflammatory effects; therefore, in the present experiment, we investigated the antiarrhythmic properties of atorvastatin in ouabain-induced arrhythmia in isolated rat atria and the role of several inflammatory cytokines in this effect.

MATERIALS AND METHODS

Male rats were pretreated with either of atorvastatin (10 mg/kg) or vehicle, orally once daily for 6 weeks. After induction of anesthesia, we isolated the atria and after incubation with ouabain, time of onset of arrhythmia and asystole as well as atrial beating rate and contractile force were recorded. We also measured the atrial levels of IL-1β, IL-6, and TNF-α after the injection of ouabain to animals.

RESULTS

Pretreatment with atorvastatin significantly delayed the onset of arrhythmia and asystole compared with vehicle-treated group (p < .01, p < .001, respectively). Incubation of ouabain boosted both atrial beating rate and contractile force in vehicle-treated group (p < .05), while these responses in atorvastatin-treated group were not significant (p > .05). Injection of ouabain elevated the atrial levels of IL-1β, IL-6, and TNF-α, while pretreatment of animals with atorvastatin could reverse the ouabain-induced increase in atrial IL-1β and IL-6 (p < .01 and p < .05, respectively).

CONCLUSIONS

It is concluded that observed antiarrhythmic effects of atorvastatin might be attributed to modulation of some inflammatory cytokines, at least IL-1β and IL-6.

The Use of Statins in the Treatment and Prevention of Atrial Fibrillation

The hydroxy-methyl-glutaryl-CoA reductase inhibitors (statins) are used extensively in the treatment of hyperlipidemia and in the primary and secondary prevention of cardiovascular and cerebrovascular diseases. Statins have also been demonstrated to confer secondary pleiotropic benefits in a variety of other disease processes, including a potential advantage in treating and preventing atrial fibrillation. These effects are primarily due to the up-regulation of endothelial nitric oxide synthase activity and a decrease in nicotinamide adenine dinucleotide phosphate oxidase production, which leads to downstream effects that improve the electromechanical function of atrial and myocardial tissue. The following serves as a focused and updated review of the published clinical data regarding the pleiotropic effects of statins in atrial fibrillation.

Effects of Atorvastatin on Serum High-Sensitive C-Reactive Protein and Total Cholesterol Levels in Asian Patients With Atrial Fibrillation

Elevated serum levels of high-sensitive C-reactive protein (hs-CRP) and total cholesterol (TC) correlate with atherosclerotic vascular disease and increased frequency of vascular events. In this study, we investigated the effect of atorvastatin treatment on serum hs-CRP and TC levels, and the recurrence rate of atrial fibrillation (AF) in patients. Furthermore, a meta-analysis was performed to confirm the findings in this study. A total of 105 patients with AF were recruited to this study, including 55 patients with AF who were treated with amiodarone and atorvastatin (the treatment group) and 50 patients with AF who were treated with only amiodarone (the control group). Patients were treated for 12 months and followed up regularly for 1 year. Serum hs-CRP and TC levels in patients before and after treatment were recorded, and AF recurrence rate at 3, 6, and 12 months of treatment was obtained. Statistical analyses were performed with R 3.1.0 software and STATA 12.0 software. For patients in both treatment and control groups, serum hs-CRP and TC levels were high before the treatments began (both P < 0.05). However, after 12 months of treatment, serum hs-CRP and TC levels in the treatment group was dramatically reduced compared with the control group (hs-CRP: 3.63 ± 2.14 mg/L vs. 2.75 ± 1.89 mg/L, t = 2.24, P = 0.027; TC: 4.66 ± 1.13 mmol/L vs. 4.20 ± 1.06 mmol/L, t = 2.15, P = 0.034). After 12 months of treatment, the AF recurrence rate in the treatment group was significantly lower than the control group (16.4% vs. 34.0%; χ = 4.37; P = 0.037). In addition, 13 studies were selected for meta-analysis. Pooled results of the meta-analysis showed that serum hs-CRP and TC levels decreased significantly in the treatment group compared with the case group [hs-CRP: SMD = 0.95, 95% confidence interval (CI) = 0.62-1.29, and P < 0.001; TC: SMD = 1.39, 95% CI = 0.65-2.13, and P < 0.001]. Our study presents compelling evidence that atorvastatin is highly effective in reducing serum hs-CRP and TC levels and lowering the recurrence rate of AF.

Effects of atorvastatin on atrial remodeling in a rabbit model of atrial fibrillation produced by rapid atrial pacing

Background

Accumulating evidence suggests that myeloperoxidase (MPO) is involved in atrial remodeling of atrial fibrillation (AF). Statins could reduce the MPO levels in patients with cardiovascular diseases. This study evaluated the effects of atorvastatin on MPO level and atrial remodeling in a rabbit model of pacing-induced AF.

Methods

Eighteen rabbits were randomly divided into sham, control and atorvastatin groups. Rabbits in the control and atorvastatin groups were subjected to rapid atrial pacing (RAP) at 600 bpm for 3 weeks, and treated with placebo or atorvastatin (2.5 mg/kg/d), respectively. Rabbits in the sham group did not receive RAP. After 3 weeks of pacing, atrial structural and functional changes were assessed by echocardiography, atrial effective refractory period (AERP) and AF inducibility were measured by atrial electrophysiological examination, and histological changes were evaluated by Masson trichrome-staining. The L-type calcium channel α1c (Cav1.2), collagen I and III, MPO, matrix metalloproteinase (MMP)-2 and MMP-9 were analyzed by real time polymerase chain reaction and/or western blot.

Results

All rabbits were found to have maintained sinus rhythm after 3 weeks of RAP. Atrial burst stimulation induced sustained AF (>30 min) in 5, 4, and no rabbits in the control, atorvastatin, and sham groups, respectively. The AERP shortened and Cav1.2 mRNA level decreased in the control group, but these changes were suppressed in the atorvastatin group. Obvious left atrial enlargement and dysfunction was found in both control and atorvastatin groups. Compared with the control group, these echocardiograhic indices of left atrium did not differ in the atorvastatin group. Prominent atrial fibrosis and increased levels of collagen I and III were observed in the control group but not in the atorvastatin group. The mRNA and protein levels of MPO, MMP-2 and MMP-9 significantly increased in the control group, but these changes were prevented in the atorvastatin group.

Conclusion

Treatment with atorvastatin prevented atrial remodeling in a rabbit model of RAP-induced AF. The reduction of levels of atrial MPO, MMP-2 and MMP-9 may contribute to the prevention of atorvastatin on atrial remodeling.

Primary prevention of atrial fibrillation with beta-blockers in patients with end-stage renal disease undergoing dialysis

Current evidence suggests that beta-blocker lower the risk of development of atrial fibrillation (AF) and in-hospital stroke after cardiac surgery. This study was to assess whether beta-blockers could decrease incidence of new-onset AF in patients with end stage renal disease (ESRD). We identified patients from a nation-wide database called Registry for Catastrophic Illness, which encompassed almost 100% of the patients receiving dialysis therapy in Taiwan from 1995 to 2008. Propensity score matching and Cox’s proportional hazards regression model were used to estimate hazard ratios (HRs) for new-onset AF. Among 100066 patients, 41.7% received beta-blockers. After a median follow-up of 1500 days, the incidence of new-onset AF significantly decreased in patients treated with beta-blockers (HR = 0.483, 95% confidence interval = 0.437-0.534). The prevention of new-onset AF was significantly better in patients taking longer duration of beta-blockers therapy (P for time trend <0.001). The AF prevention effect remains robust in subgroup analyses. In conclusion, beta-blockers seem effective in the primary prevention of AF in ESRD patients. Hence, beta-blockers may be the target about upstream treatment of AF.

Atrial fibrillation in patients with diabetes: molecular mechanisms and therapeutic perspectives

Atrial fibrillation (AF) remains the most frequent sustained cardiac arrhythmia worldwide and its incidence increases with ageing, cardiovascular risk factors and comorbidities. Prevalence of diabetes mellitus (DM) is growing fast and is assuming pandemic proportions mostly due to overnutrition and sedentary habits. Experimental and clinical evidences suggest that DM and AF are strongly interconnected. The present review addresses in detail new molecular pathways implicated in the etiology of AF and their relevance for mechanism-based therapeutic strategies in this setting. Advances in risk stratification, drug therapy (i.e., novel anticoagulants) and catheter ablation are also described.

Effects of simvastatin and atorvastatin on biochemical and hematological markers in patients with risk of cardiovascular diseases

OBJECTIVE

This study aimed to investigate the effects of simvastatin (SVS) and atorvastatin (AVS) on the biochemical and hematological markers in patients with risk of cardiovascular diseases.

METHODS

One hundred and fifty outpatients were enrolled from the Department of Cardiology. Patients were treated with AVS or SVS. The lipids and hematological parameters were measured at baseline and after 4-week treatment, and the risk factors of cardiovascular diseases were recorded.

RESULTS

After 4-week treatment, the lipids significantly changed. However, for hematological parameters, only mean platelet volume (MPV) significantly decreased after statins treatment (SVS: t = 68.748, P = 0.000; AVS: t = 39.472, P = 0.000), and the extent of decline was similar between SVS group and AVS group (t = 1.063, P = 0.289). There were no correlations between MPV and lipids. SVS and AVS had comparable effects on the lipid parameters after 4-week treatment, and there were no significant correlations of ΔMPV with the Δtotal cholesterol, Δhigh density lipoprotein-cholesterol, Δlow density lipoprotein-cholesterol, Δtriglyceride, Δapolipoproteint A1, Δapolipoproteint B and Δlipoproteint (a) after treatments (all P > 0.05).

CONCLUSION

After statins treatment, the lipids significantly change; only MPV significantly decreases among hematological parameters, but it has no relationship with lipids reduction. The synthetic atorvastatin has similar effects to native simvastatin in the management of patients with risk for cardiovascular diseases.

Effect of Atorvastatin on Serum Levels of Total Cholesterol and High-Sensitivity C-reactive Protein in High-Risk Patients with Atrial Fibrillation in Asia

PURPOSE

The aim of this meta-analysis was to investigate the effects of atorvastatin on serum levels of high-sensitivity C-reactive protein (hs-CRP) and total cholesterol in atrial fibrillation (AF) patients in Asia.

METHODS

By searching English and Chinese language-based electronic databases (ie, PubMed, EBSCO, Ovid, SpringerLink, Wiley, Web of Science, Wanfang database, China National Knowledge Infrastructure, and VIP database), we identified 13 studies relevant to our topic of interest. Data were collected from the 13 studies and analyzed with Comprehensive Meta-Analysis software (version 2.0, Biostat Inc., Englewood, New Jersey).

FINDINGS

Initially, our database searches retrieved 356 studies (45 in English, 311 in Chinese). Thirteen studies were selected for the meta-analysis following stringent criteria. The data included 1239 patients with AF, of whom 634 were treated with atorvastatin and included in the treatment group, and 605 patients were treated with conventional treatment and included in the control group. The results of our meta-analysis suggested that the serum levels of hs-CRP (mg/L) and total cholesterol (mmol/L) in the treatment group were significantly lower than those of the control group (hs-CRP: standardized mean difference = 0.962; 95% CI, 0.629-1.295, P < 0.001; total cholesterol: standardized mean difference = 1.400; 95% CI, 0.653-2.146, P < 0.001).

IMPLICATIONS

The findings of this study suggest that atorvastatin may be very effective in decreasing serum levels of hs-CRP and total cholesterol to prevent cardiovascular events.