Statins and postoperative risk of atrial fibrillation following coronary artery bypass grafting

Metabolic remodelling in atrial fibrillation: manifestations, mechanisms and clinical implications

Atrial fibrillation (AF) is a continually growing health-care burden that often presents together with metabolic disorders, including diabetes mellitus and obesity. Current treatments often fall short of preventing AF and its adverse outcomes. Accumulating evidence suggests that metabolic disturbances can promote the development of AF through structural and electrophysiological remodelling, but the underlying mechanisms that predispose an individual to AF are aetiology-dependent, thus emphasizing the need for tailored therapeutic strategies to treat AF that target an individual's metabolic profile. AF itself can induce changes in glucose, lipid and ketone metabolism, mitochondrial function and myofibrillar energetics (as part of a process referred to as 'metabolic remodelling'), which can all contribute to atrial dysfunction. In this Review, we discuss our current understanding of AF in the setting of metabolic disorders, as well as changes in atrial metabolism that are relevant to the development of AF. We also describe the potential of available and emerging treatment strategies to target metabolic remodelling in the setting of AF and highlight key questions and challenges that need to be addressed to improve outcomes in these patients.

Prevention of Atrial Fibrillation After Cardiac Surgery: A Review of Literature and Comparison of Different Treatment Modalities

Atrial fibrillation is the most common arrhythmia to occur after cardiac surgery, with an incidence of 10% to 50%. It is associated with postoperative complications including increased risk of stroke, prolonged hospital stays and increased costs. Despite new insights into the mechanisms of atrial fibrillation, no specific etiologic factor has been identified as the sole perpetrator of the arrhythmia. Current evidence suggests that the pathophysiology of atrial fibrillation in general, as well as after cardiac surgery, is multifactorial. Studies have also shown that new-onset postoperative atrial fibrillation following cardiac surgery is associated with a higher risk of short-term and long-term mortality. Furthermore, it has been demonstrated that prophylactic medical therapy decreases the incidence of postoperative atrial fibrillation after cardiac surgery. Of note, the incidence of postoperative atrial fibrillation has not changed during the last decades despite the numerous preventive strategies and operative techniques proposed, although the perioperative and postoperative care of cardiac patients as such has improved.

Prediction of new onset atrial fibrillation in patients with acute coronary syndrome undergoing percutaneous coronary intervention using the C2HEST and mC2HEST scores: A report from the multicenter REALE-ACS registry

BACKGROUND

New onset atrial fibrillation (NOAF) is associated with worse clinical outcomes after acute coronary syndrome (ACS). Identification of ACS patients at risk of NOAF remains challenging. To test the value of the simple C2HEST score for predicting NOAF in patients with ACS.

METHODS

We studied patients from the prospective ongoing multicenter REALE-ACS registry of patients with ACS. NOAF was the primary endpoint of the study. The C2HEST score was calculated as coronary artery disease or chronic obstructive pulmonary disease (1 point each), hypertension (1 point), elderly (age ≥ 75 years, 2 points), systolic heart failure (2 points), thyroid disease (1 point). We also tested the mC2HEST score.

RESULTS

We enrolled 555 patients (mean age 65.6 ± 13.3 years; 22.9% women), of which 45 (8.1%) developed NOAF. Patients with NOAF were older (p < 0.001) and had more prevalent hypertension (p = 0.012), chronic obstructive pulmonary disease (p < 0.001) and hyperthyroidism (p = 0.018). Patients with NOAF were more frequently admitted with STEMI (p < 0.001), cardiogenic shock (p = 0.008), Killip class ≥2 (p < 0.001) and had higher mean GRACE score (p < 0.001). Patients with NOAF had a higher C2HEST score compared with those without (4.2 ± 1.7 vs 3.0 ± 1.5, p < 0.001). A C2HEST score > 3 was associated with NOAF occurrence (odds ratio 4.33, 95% confidence interval 2.19-8.59, p < 0.001). ROC curve analysis showed good accuracy of the C2HEST score (AUC 0.71, 95%CI 0.67-0.74) and mC2HEST score (AUC 0.69, 95%CI 065-0.73) in predicting NOAF.

CONCLUSIONS

The simple C2HEST score may be a useful tool to identify patients at higher risk of developing NOAF after presentation with ACS.

Ischemia with Nonobstructive Coronary Artery Disease and Atrial Cardiomyopathy-Two Sides of the Same Story?

Ischemia with nonobstructive coronary artery disease (INOCA) is increasingly recognized as a significant cause of angina, myocardial remodeling, and eventually heart failure (HF). Coronary microvascular dysfunction (CMD) is a major endotype of INOCA, and it is caused by structural and functional alterations of the coronary microcirculation. At the same time, atrial cardiomyopathy (ACM) defined by structural, functional, and electrical atrial remodeling has a major clinical impact due to its manifestations: atrial fibrillation (AF), atrial thrombosis, stroke, and HF symptoms. Both these pathologies share similar risk factors and have a high comorbidity burden. CMD causing INOCA and ACM frequently coexist. Thus, questions arise whether there is a potential link between these pathologies. Does CMD promote AF or the reverse? Which are the mechanisms that ultimately lead to CMD and ACM? Are both part of a systemic disease characterized by endothelial dysfunction? Lastly, which are the therapeutic strategies that can target endothelial dysfunction and improve the prognosis of patients with CMD and ACM? This review aims to address these questions by analyzing the existing body of evidence, offering further insight into the mechanisms of CMD and ACM, and discussing potential therapeutic strategies.

Effect of preoperative statins on respiratory complications after coronary artery bypass grafting

OBJECTIVES

Limited data exist on the effect of preoperative statin therapy on postoperative respiratory complications. Machine learning algorithms (MLA) can process large, heterogenous data, and have immensely improved the ability for risk prediction. In this study, we sought to examine the role of preoperative statins on respiratory complications in patients undergoing coronary artery bypass grafting (CABG) using MLA.

METHODS

The study population contained the data of patients who underwent CABG between the years 2015 and 2019 (n = 5638). Three hundred and thirty-seven independent variables were recorded and the data was randomly split with stratified sampling into training and testing data with 20% of the data (1113 records) reserved for model testing. Various models including linear models, Random forest, SVM, and XGboost were trained to predict the incidence of postoperative respiratory complications. Forty-seven important features were found to impact model prediction (p ≤ .05) using the global surrogate model method. A conventional multivariable linear regression model was then used to identify predictors of respiratory complications.

RESULTS

One thousand three hundred sixty-two (24.5%) patients developed a respiratory complication in our series. The respiratory complication was seen in 561 (29.7%) of the patients who were not on statin compared to only 801 (21.8%) who were on a statin, p < .0001. The area under the curve for receiver operating characteristic curve using statins and respiratory complications was 0.706. Statins showed positive feature importance in all the MLA models.

CONCLUSIONS

MLA showed that statins impacted the prediction of respiratory complications in all the models studied. The study confirmed that preoperative statins reduced the risk of respiratory complications by 21%.

Mechanism and prevention of atrial remodeling and their related genes in cardiovascular disorders

Atrial fibrillation (AF) is associated with profound structural and functional changes in the atrium. Inflammation mediated atrial fibrosis is one of the key mechanisms in the pathogenesis of AF. The collagen deposition in extracellular matrix (ECM) is mainly mediated by transforming growth factor β1 (TGF-β1) which promotes AF via controlling smads mediated-collagen gene transcription and regulating the balance of metalloproteinases (MMPs)/ tissue inhibitor of metalloproteinases (TIMPs). Although many processes can alter atrial properties and promote AF, animal models and clinical studies have provided insights into two major forms of atrial remodeling: Atrial tachycardia remodeling (ATR), which occurs with rapid atrial tachyarrhythmia's such as AF and atrial flutter, and atrial structural remodeling (ASR), which is associated with CHF and other fibrosis-promoting conditions. The mechanism of atrial remodeling such as atrial enlargement, ultra structural changes of atrial muscle tissue and myocardial interstitial fibrosis in AF is still unclear. At present, many studies focus on calcium overload, renin angiotensin aldosterone system and transforming growth factor β1, that effect on atrial structural remodeling. Recent experimental studies and clinical investigations have provided structural remodeling is important contributor to the AF. This paper reviews the current understanding of the progresses about mechanism of atrial structural remodeling, and highlights the potential therapeutic approaches aimed at attenuating structural remodeling to prevent AF. Now some recent advancements of this area are reviewed in this paper.

Preoperative Statin Use Is Associated With Less Postoperative Atrial Fibrillation After Myectomy in Patients With Hypertrophic Obstructive Cardiomyopathy

The present study aims to investigate whether preoperative statin use is associated with less postoperative atrial fibrillation occurrence after septal myectomy in patients with hypertrophic obstructive cardiomyopathy (HOCM). Clinical data of consecutive patients with HOCM who underwent septal myectomy between February 2009 and May 2019 at our institution was retrospectively reviewed. The cohort was divided into 2 groups according to the status of preoperative statin use (statin group vs no statin group). Logistic regression was used to explore associations of clinical variables with postoperative atrial fibrillation occurrence. A total of 1307 patients with HOCM underdoing septal myectomy were included in the present study, with 109 patients in the statin group and 1198 in the no statin group. Among 322 patients (24.6%) developing postoperative atrial fibrillation, 21 cases (19.3%) occurred in the statin group, while 301 cases (25.1%) were in the no statin group (P = 0.202). After propensity score matching with confounding variables at baseline, 91 paired patients were included in the matched cohort. Postoperative atrial fibrillation developed in 17 (18.7%) and 38 (41.8%) in the statin and no statin groups, respectively (P = 0.001). Preoperative statin use was associated with less postoperative atrial fibrillation occurrence (odds ratio 0.220, 95% confidence interval 0.083-0.588, P<0.003). The present study suggested that preoperative statin use was associated with less postoperative atrial fibrillation occurrence after septal myectomy in patients with HOCM. This finding may provide clues for subsequent prospective study to investigate this clinical issue.

Association of clinical predictors with recurrence of atrial fibrillation after catheter ablation

BACKGROUND

Recurrence rate after radiofrequency catheter ablation (RFCA) remains high, and further investigation on predictors of recurrence is needed.

OBJECTS

To identify risk factors of atrial fibrillation (AF) recurrence in patients undergoing RFCA.

METHODS

We retrospectively studied 257 patients with AF who underwent RFCA preceded by transthoracic echocardiographic and pulmonary vein CT examination from 2016 to 2019. Electrocardiogram examination was performed at baseline, 1, 3, 6 months, and 1 year after RFCA. We divided patients into two groups based on AF recurrence including recurrence group (n = 79) and nonrecurrence group (n = 178). The crude and independent association between clinical variables and AF recurrence was evaluated with logistic regression analysis. Specificity and positive predictive value of relevant factors for AF recurrence were performed by ROC curve.

RESULTS

Of these AF patients, 174 (68%) was paroxysmal AF and 83 (32%) was persistent AF. The multivariate logistic regression demonstrated that AF duration (OR = 1.008, 95% CI 1.002-1.013, p = .008), pulmonary arterial hypertension (PAH; OR = 2.313, 95% CI 1.031-5.192, p = .042), and low-density lipoprotein cholesterol (LDL-C; OR = 1.646, 95% CI 1.129-2.398, p = .010) were independently correlated with recurrence of AF. For predicting AF recurrence, the specificity and sensitivity of AF duration were 30.1% and 87.3%, and for LDL-C, the specificity and sensitivity of AF duration were 60.6% and 60.5%, respectively.

CONCLUSIONS

Atrial fibrillation duration, PAH, and LDL-C might be independent risk factors for the recurrence of AF after RFCA.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY GUIDELINES FOR MANAGEMENT OF DYSLIPIDEMIA AND PREVENTION OF CARDIOVASCULAR DISEASE

OBJECTIVE

The development of these guidelines is mandated by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs).

METHODS

Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols.

RESULTS

The Executive Summary of this document contains 87 recommendations of which 45 are Grade A (51.7%), 18 are Grade B (20.7%), 15 are Grade C (17.2%), and 9 (10.3%) are Grade D. These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world medical care. The evidence base presented in the subsequent Appendix provides relevant supporting information for Executive Summary Recommendations. This update contains 695 citations of which 203 (29.2 %) are EL 1 (strong), 137 (19.7%) are EL 2 (intermediate), 119 (17.1%) are EL 3 (weak), and 236 (34.0%) are EL 4 (no clinical evidence).

CONCLUSION

This CPG is a practical tool that endocrinologists, other health care professionals, health-related organizations, and regulatory bodies can use to reduce the risks and consequences of dyslipidemia. It provides guidance on screening, risk assessment, and treatment recommendations for a range of individuals with various lipid disorders. The recommendations emphasize the importance of treating low-density lipoprotein cholesterol (LDL-C) in some individuals to lower goals than previously endorsed and support the measurement of coronary artery calcium scores and inflammatory markers to help stratify risk. Special consideration is given to individuals with diabetes, familial hypercholesterolemia, women, and youth with dyslipidemia. Both clinical and cost-effectiveness data are provided to support treatment decisions.

ABBREVIATIONS

4S = Scandinavian Simvastatin Survival Study A1C = glycated hemoglobin AACE = American Association of Clinical Endocrinologists AAP = American Academy of Pediatrics ACC = American College of Cardiology ACE = American College of Endocrinology ACS = acute coronary syndrome ADMIT = Arterial Disease Multiple Intervention Trial ADVENT = Assessment of Diabetes Control and Evaluation of the Efficacy of Niaspan Trial AFCAPS/TexCAPS = Air Force/Texas Coronary Atherosclerosis Prevention Study AHA = American Heart Association AHRQ = Agency for Healthcare Research and Quality AIM-HIGH = Atherothrombosis Intervention in Metabolic Syndrome With Low HDL/High Triglycerides trial ASCVD = atherosclerotic cardiovascular disease ATP = Adult Treatment Panel apo = apolipoprotein BEL = best evidence level BIP = Bezafibrate Infarction Prevention trial BMI = body mass index CABG = coronary artery bypass graft CAC = coronary artery calcification CARDS = Collaborative Atorvastatin Diabetes Study CDP = Coronary Drug Project trial CI = confidence interval CIMT = carotid intimal media thickness CKD = chronic kidney disease CPG(s) = clinical practice guideline(s) CRP = C-reactive protein CTT = Cholesterol Treatment Trialists CV = cerebrovascular CVA = cerebrovascular accident EL = evidence level FH = familial hypercholesterolemia FIELD = Secondary Endpoints from the Fenofibrate Intervention and Event Lowering in Diabetes trial FOURIER = Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects With Elevated Risk trial HATS = HDL-Atherosclerosis Treatment Study HDL-C = high-density lipoprotein cholesterol HeFH = heterozygous familial hypercholesterolemia HHS = Helsinki Heart Study HIV = human immunodeficiency virus HoFH = homozygous familial hypercholesterolemia HPS = Heart Protection Study HPS2-THRIVE = Treatment of HDL to Reduce the Incidence of Vascular Events trial HR = hazard ratio HRT = hormone replacement therapy hsCRP = high-sensitivity CRP IMPROVE-IT = Improved Reduction of Outcomes: Vytorin Efficacy International Trial IRAS = Insulin Resistance Atherosclerosis Study JUPITER = Justification for the Use of Statins in Primary Prevention: An Intervention Trial Evaluating Rosuvastatin LDL-C = low-density lipoprotein cholesterol Lp-PLA2 = lipoprotein-associated phospholipase A2 MACE = major cardiovascular events MESA = Multi-Ethnic Study of Atherosclerosis MetS = metabolic syndrome MI = myocardial infarction MRFIT = Multiple Risk Factor Intervention Trial NCEP = National Cholesterol Education Program NHLBI = National Heart, Lung, and Blood Institute PCOS = polycystic ovary syndrome PCSK9 = proprotein convertase subtilisin/kexin type 9 Post CABG = Post Coronary Artery Bypass Graft trial PROSPER = Prospective Study of Pravastatin in the Elderly at Risk trial QALY = quality-adjusted life-year ROC = receiver-operator characteristic SOC = standard of care SHARP = Study of Heart and Renal Protection T1DM = type 1 diabetes mellitus T2DM = type 2 diabetes mellitus TG = triglycerides TNT = Treating to New Targets trial VA-HIT = Veterans Affairs High-Density Lipoprotein Cholesterol Intervention Trial VLDL-C = very low-density lipoprotein cholesterol WHI = Women's Health Initiative.

Upstream therapeutic strategies of valsartan and fluvastatin on hypertensive patients with non-permanent atrial fibrillation

AIM

To investigate the upstream therapeutic effects of fluvastatin and valsartan on hypertensive patients with non-permanent atrial fibrillation (AF).

METHODS

A total of 189 patients who were admitted to outpatient and inpatient department from eight medical centers in China, diagnosed as hypertension with non-permanent AF, were divided into four groups randomly: the CCBs group (group A, n = 45); CCB + fluvastatin group (group B, n = 48); valsartan group (group C, n = 46); valsartan + fluvastatin group (group D, n = 50). The four groups were followed up for 24 months. The blood routine, biochemical examination, echocardiography, high sensitive C-reactive protein (hs-CRP), N-terminal pro-brain natriuretic peptide (NT-proBNP), the maintenance rate of sinus rhythm, and the recurrence of paroxysmal AF or persistent AF incidence were observed in these groups before and after 24 months' treatment.

RESULTS

After 24 months of follow-up, there were 178 cases of patients who have completed the study. (a) There was no significant difference in blood routine, liver, and renal function in each group (P > 0.05). (b) The blood lipids level in groups B and D was significantly reduced after treatment (P < 0.01). There was no significant difference of hs-CRP level in group A (P > 0.05). The left ventricular remodeling was significantly alleviated in group C and group D (P < 0.05). The NT-ProBNP level was significantly decreased in group D (P < 0.05). (c) The sinus rhythm maintenance rate of group B, group C, and group D was higher than group A (77.78%, 70.45%, 79.17% vs 43.90%), the occurrence of persistent AF was significantly lower than group A (11.11%, 14.29%, 8.33% vs 31.71%; P < 0.05).

CONCLUSIONS

CCB plus fluvastatin and valsartan can reduce the recurrence rate of non-permanent AF and to delay the progression from non-permanent AF to permanent AF in patients with hypertension. The combined application of valsartan and fluvastatin is more effective than valsartan or CCB alone in the upstream therapies of AF.

Impact of statin therapy on all-cause mortality and ICD interventions in heart failure patients - a systematic review

OBJECTIVES

Implantable cardioverter defibrillators (ICDs) have a unique role for the primary and secondary prevention of sudden cardiac death (SCD). The aim of our systematic review is to present the existing data about the impact of statins on all-cause mortality and ICD interventions in heart failure (HF) patients who had an ICD implanted either for primary or for secondary prevention of SCD.

METHODS AND RESULTS

We searched PubMed database and the reference list of the relevant studies for retrieving studies evaluating the effect of statins on all-cause mortality and ICD interventions in HF patients. We finally included 17 relevant studies in our systematic review. Of them, nine studies included data about the impact of statins on all-cause mortality, eight studies about the impact of statins on appropriate ICD interventions and three studies about the impact of statins on inappropriate ICD interventions in HF patients. These data showed that statins seem to have a beneficial role in the reduction of all-cause mortality and ICD interventions in HF patients.

CONCLUSIONS

Statins seem to have a beneficial role in the reduction of all-cause mortality and ICD interventions in HF patients. However, further research about pleiotropic effects of statins is needed as well randomized control trials to elucidate the exact role of statin therapy in ICD outcomes.

Perioperative statin therapy in cardiac surgery: a meta-analysis of randomized controlled trials

BACKGROUND

Several studies suggest beneficial effects of perioperative statin therapy on postoperative outcome after cardiac surgery. However, recent randomized controlled trials (RCTs) show potential detrimental effects. The objective of this systematic review is to examine the association between perioperative statin therapy and clinical outcomes in cardiac surgery patients.

METHODS

Electronic databases were searched up to 1 November 2016 for RCTs of preoperative statin therapy versus placebo or no treatment in adult cardiac surgery. Postoperative outcomes were acute kidney injury, atrial fibrillation, myocardial infarction, stroke, infections, and mortality. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using fixed-effects meta-analyses. Primary analysis was restricted to trials with low risk of bias according to Cochrane methodology, and sensitivity analyses examined whether the risk of bias of included studies was associated with different results. We performed trial sequential analysis (TSA) to test the strength of the results.

RESULTS

We included data from 23 RCTs involving 5102 patients. Meta-analysis of trials with low risk of bias showed that statin therapy was associated with an increase in acute kidney injury (314 of 1318 (23.82%) with statins versus 262 of 1319 (19.86%) with placebo; OR 1.26 (95%CI 1.05 to 1.52); p = 0.01); these results were supported by TSA. No difference in postoperative atrial fibrillation, myocardial infarction, stroke, infections, or mortality was present. On sensitivity analysis, statin therapy was associated with a slight increase in hospital mortality. Meta-analysis including also trials with high or unclear risk of bias showed no beneficial effects of statin therapy on any postoperative outcomes.

CONCLUSIONS

There is no evidence that statin therapy in the days prior to cardiac surgery is beneficial for patients' outcomes. Particularly, statins are not protective against postoperative atrial fibrillation, myocardial infarction, stroke, or infections. Statins are associated with a possible increased risk of acute kidney injury and a detrimental effect on hospital survival could not be excluded. Future RCTs should further evaluate the safety profile of this therapy in relation to patients' outcomes and assess the more appropriate time point for discontinuation of statins before cardiac surgery.

Cardiology: Post-Cardiothoracic Surgery Atrial Fibrillation: A Review of Preventive Strategies

Objective:

To review the available literature addressing preventive strategies of post-cardiothoracic surgery atrial fibrillation (post-CTS atrial fibrillation).

Data Sources:

Pertinent articles related to the etiology, risk factors, and preventive strategies were identified through a MEDLINE search (1966–March 2007) using the MeSH terms atrial fibrillation, cardiothoracic surgery, cardiac surgery, etiology, neurohormonal, sympathetic, volume, fluid, inflammation, risk factors, operative, pacing, β-adrenergic blockers, amiodarone, sotalol, calcium-channel blockers, magnesium, HMG-CoA reductase inhibitors, statins, fatty acids, PUFA, steroids, and nonsteroidal antiinflammatory drugs.

Study Selection and Data Extraction:

Articles evaluated were limited to human studies, published in the English language, with a Jadad score greater than 3. References of identified articles were reviewed for additional pertinent articles.

Data Synthesis:

Post-CTS atrial fibrillation most commonly occurs on the second or third postoperative day, with an incidence of 20–50%. Etiology theories include neurohormonal activation, volume overload, and inflammation. Studies examining nonpharmacologic therapies have shown that maintenance of the anterior epicardial fat pad is not a viable prophylactic strategy. Biatrial cardiac pacing, especially in combination with amiodarone, is a viable preventive option. Withdrawal of preoperative β-blockers places patients at higher risk for atrial fibrillation; these drugs should be continued postoperatively. Evidence exists supporting the use of amiodarone, sotalol, and magnesium in addition to β-blockers. Since most of these strategies work by attenuating neurohormonal activation, adverse events, including hypotension and bradycardia, are of concern. Adding agents with antiinflammatory properties, including hydroxymethylglutaryl coenzyme A reductase inhibitors or corticosteroids, may prove to be of benefit. Additional studies using novel therapies are needed in addition to established preventive strategies.

Conclusions:

Available evidence supports the continuation of preoperative β-blockers, as well as prophylactic amiodarone, sotalol, and magnesium. Other novel therapies, mostly targeting inflammation, are under investigation and may provide additional strategies.

Perspectives and challenges of antioxidant therapy for atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia associated with significant morbidity and mortality. The mechanisms underlying the pathogenesis of AF are poorly understood, although electrophysiological remodeling has been described as an important initiating step. There is growing evidence that oxidative stress is involved in the pathogenesis of AF. Many known triggers of oxidative stress, such as age, diabetes, smoking, and inflammation, are linked with an increased risk of arrhythmia. Numerous preclinical studies and clinical trials reported the importance of antioxidant therapy in the prevention of AF, using vitamins C and E, polyunsaturated fatty acids, statins, or nitric oxide donors. The aim of our work is to give a current overview and analysis of opportunities, challenges, and benefits of antioxidant therapy in AF.

Prevention of atrial fibrillation and inflammatory response after on-pump coronary artery bypass using different statin dosages: a randomized, controlled trial

BACKGROUND

This randomized controlled trial aimed to evaluate the effects of seven-day preoperative treatment with two different dosages of atorvastatin on the incidence of postoperative atrial fibrillation (POAF) and release of inflammatory markers such as high-sensitive C-reactive protein (hsCRP) and interleukin-6 in patients undergoing elective first-time on-pump coronary artery bypass grafting (CABG).

METHODS

The cohort study comprised 212 consecutive patients, already taking statins, who underwent elective first-time CABG with cardiopulmonary bypass without history of atrial fibrillation (AF). Patients were randomly divided into two groups: those who received atorvastatin 40 mg (TOR40 group, 111 patients) and those who received 80 mg (TOR80 group, 101 patients) once a day for 7 days before the planned operation. The primary endpoint was the incidence of AF. The secondary endpoints were the postoperative variations of inflammatory markers, hospital length of stay, and the incidence of major adverse cardiac and clinical events.

RESULTS

A total of 26 patients (23.6 %) pretreated with atorvastatin 40 mg and 16 (15.8 %) patients pretreated with atorvastatin 80 mg had postoperative AF but the difference did not reach the statistical significance (p = 0.157). Median values of interleukin-6 and hsCRP at 12 and 24 h did not have differences between the two groups. No statistically significant differences in the other secondary endpoints were detected.

CONCLUSIONS

According to our result, 7-day preoperative treatment with a high dose of atorvastatin is associated with a trend to a decrease in the incidence of POAF compared with treatment at a lower dose, although it does not impact on the level of inflammatory markers.

CLINICAL TRIAL REGISTRATION

European Clinical Trials Database (EudraCT: 2006-005757-30).

Statin therapy in the primary prevention of early atrial fibrillation after coronary artery bypass grafting

OBJECTIVE

Assessment of the role of statin therapy in the prevention of postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) in patients without prior atrial fibrillation.

METHODS

A retrospective analysis of 206 patients, aged 57.2±7.9 years (mean±SD), who underwent isolated CABG is carried out. All patients are divided into two groups. The first group (nSt-patients) includes the patients who did not receive statin therapy prior to CABG (n=82). The second group (St-patients) includes the patients who received statin therapy prior to CABG (n=124). Both groups received the statin therapy from the first day after CABG. The risk of occurrence of POAF is evaluated using the Cox-regression model.

RESULTS

The rate of POAF was 25.6% in nSt-patients and 6.5% in St-patients (P=0.020). On the 4th day after CABG, white blood cells (WBC) count was 11.0 (9.0, 13.0)×10⁹/mL (medians with inter-quartile ranges) in nSt-patients and 9.0 (7.6, 10.2)×10⁹/mL in St-patients (P<0.001). The peak WBC numbers occurred on the day of POAF onset. The Cox-regression analysis shows that only two factors (statin therapy and number of grafts) had significant influence on the POAF onset. Odds ratio of POAF event prediction by statin therapy was 0.20 (95%CI: 0.08-0.51), P<0.001. Each subsequent graft increased the risk of POAF in 2.1 times.

CONCLUSION

Statin therapy carried out prior to the CABG is an effective approach to primary prevention of POAF in early postoperative period. Statin therapy after CABG in nSt-patients does not give prophylactic effect observed in St-patients.

Efficacy of atorvastatin in prevention of atrial fibrillation after heart valve surgery in the PROFACE trial (PROphylaxis of postoperative atrial Fibrillation After Cardiac surgEry)

Background

To evaluate the efficacy of perioperative atorvastatin administration for prophylaxis of postoperative atrial fibrillation (POAF) after heart valve surgery.

Methods

Our study included 90 patients with heart valve disease who were scheduled to undergo elective cardiac surgery. Cases with previous AF or preoperative beta-blocker therapy were excluded. Patients were randomized into the atorvastatin group, which included 47 patients who received 40 mg/day of atorvastatin 7 days before and after the surgery and the control group, which included 43 patients. Primary endpoint was the occurrence of POAF. Secondary endpoints included modifications in the preoperative and postoperative levels of the markers of inflammation (C-reactive protein [CRP]), myocardial injury (ultrasensitive troponin T and creatinine phosphokinase MB [CPK-MB]), and cardiac dysfunction (pro-brain natriuretic peptide [proBNP]) related to POAF and changes in the echocardiographic parameters, such as atrial electromechanical interval, A wave, E/A ratio, and Doppler imaging systolic velocity wave amplitude, related to POAF.

Results

No relationship between atorvastatin administration and reduction in the incidence of POAF was observed (42.6% in the atorvastatin vs. 30.2% in the control group) (p=0.226). No difference in the levels of CPK-MB, ultrasensitive troponin T, CRP, or proBNP and in the analyzed echocardiographic parameter was detected between both groups.

Conclusions

Atorvastatin in the described dose, was not adequate for the prophylaxis of POAF after heart valve surgery. It was ineffective in controlling the inflammatory phenomena, myocardial injury, and echocardiographic predictors of POAF.

Effects of Statins on First and Recurrent Supraventricular Arrhythmias in Patients With Mild Heart Failure (from the Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy)

Previous studies suggested that statin therapy reduces the risk of occurrence and recurrence of atrial fibrillation mainly in patients with coronary artery disease. Data regarding the effect of statins on the risk for the entire range of supraventricular arrhythmias (SVA) in mild heart failure (HF) with different disease causes are lacking. Multivariate Cox proportional hazards regression models were used to assess the effect of statin therapy, evaluated as a time-dependent covariate, on the risk of SVA and recurrent SVA (defined as atrial fibrillation, atrial flutter, atrial tachycardia, and supraventricular tachycardia) that were inappropriately treated with implantable cardioverter-defibrillator device in 1,790 patients enrolled in the Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy trial. Statin users constituted 68% of the study patients (n = 1209). They were older and more frequently men; they were more likely to have ischemic cardiomyopathy, diabetes, hypertension, and previous atrial arrhythmias. During the 3.7-year median follow-up time, 160 patients had an SVA event, and the total number of recurrent events was 335. Time-dependent statin therapy was independently associated with a significant 29% reduction of the first SVA event (p = 0.046) and 33% reduction of recurrent SVA events (p = 0.003), consistent across all prespecified subgroups. In conclusion, in mild HF with either cardiac resynchronization therapy with a defibrillator or an implantable cardioverter-defibrillator device, statin therapy was associated with significant reduction of occurrence and recurrence of inappropriately treated SVA.

De novo atrial fibrillation post cardiac surgery: the Durban experience

Atrial fibrillation (AF) is the most common complication post cardiac surgery and results in elevated morbidity and mortality rates and healthcare costs. A pilot, retrospective study of the medical records of all adult patients developing de novo AF post surgery was undertaken at the cardiac surgical unit in Durban between 2009 and 2012. We aimed to describe the local experience of AF with a view to suggesting an adapted local treatment policy in relation to previously published data. Fifty-nine patients developed AF during the study period. AF occurred predominantly three or more days post surgery. Thirty-five patients required cardioversion and amiodarone to restore sinus rhythm. Return to the general ward (RGW) was 4.6 days longer than the institutional norm. Liberal peri-operative β-blocker and statin use is currently preferred to a formal prophylaxis strategy. Randomised, controlled trials are required to evaluate measures curbing prolonged length of stay and morbidity burdens imposed by AF on the local resource-constrained environment.

Statin Antiarrhythmic Effect on Atrial Fibrillation in Statin-Naive Patients Undergoing Cardiac Surgery: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Statin therapy has been thought to improve outcomes in cardiac surgeries. We aimed to determine the statin effects on the development of postoperative atrial fibrillation (AF), hospital length of stay (LOS), and inflammatory status in patients undergoing cardiac surgeries.

METHODS

A systematic literature search in databases was performed, until January 2015. Randomized clinical trial (RCT) studies evaluating statin effect on statin-naive patients with sinus rhythm undergoing cardiac surgeries were eligible to be analyzed.

RESULTS

Twelve RCTs involving 1116 patients, 559 receiving statin and 557 receiving control regimen, were analyzed. Postoperative AF occurred in 17.9% and 36.1% of patients in the statin and control groups, respectively. The statin therapy was associated with decreases in the postoperative AF (risk ratio [RR] 0.50, 95% confidence interval [CI] 0.41-0.61, P < .000010), hospital LOS (mean difference in days, RR -0.44, 95% CI -0.67 to -0.20, P = .0002), and postoperative C-reactive protein (CRP) compared with control (mean difference in mg/L, RR -12.37, 95% CI -23.87 to -0.87, P = .04). The beneficial effects on AF and CRP were more marked in patients receiving atorvastatin compared to other statins. Decrease in postoperative AF was greater in coronary artery bypass graft surgery compared to that in isolated valvular surgery.

CONCLUSION

Perioperative statin therapy in statin-naive patients with sinus rhythm undergoing cardiac surgeries was associated with decreases in the development of postoperative AF, the hospital LOS, and the CRP level. However, there were insufficient data to provide evidences regarding statin impacts in patients undergoing isolated valvular surgery.

Upstream therapeutic strategies of Valsartan and Fluvastatin on Hypertensive patients with non-permanent Atrial Fibrillation (VF-HT-AF): study protocol for a randomized controlled trial

BACKGROUND

Previous studies regarding rhythm control in patients with atrial fibrillation (AF) could not sufficiently demonstrate the efficacy of available anti-arrhythmic drugs. 'Upstream therapy' has emerged as a potential strategy for the prevention and treatment of AF. The use of angiotensin II receptor blockers and statins has been suggested to decrease new-onset AF, but which remains inadequately explored. This study was designed to examine whether valsartan or fluvastatin can reduce the risk of non-permanent AF in patients with hypertension.

METHODS/DESIGN

The VF-HT-AF study is a multicenter, randomized, open-label, four-arm parallel group study with comparative evaluation of valsartan and fluvastatin as upstream therapies for the treatment of non-permanent AF complicated by hypertension. The primary outcome measure is change in the development of paroxysmal AF into persistent or permanent AF, the development of persistent AF to permanent AF, and change in incidence of overall and persistent AF recurrence, as evaluated by 7-days ambulatory electrocardiograph monitoring (Holter) and patients' diaries during 2 years' follow-up. Secondary outcome measures of this study include the occurrence of: (1) fatal and nonfatal myocardial infarction; (2) heart failure (New York Heart Association stage III or IV); (3) cardiogenic shock; (4) serious bleeding necessitating hospitalization; (5) malignant ventricular arrhythmia; (6) revascularization therapy; (7) radiofrequency catheter ablation of AF; (8) changes of left atrial dimension, as measured by ultrasound echocardiography; (9) stroke; (10) cardiovascular mortality; and (11) all-cause mortality. A total of 1879 patients will be investigated from 15 medical centers throughout China to obtain the relevant information.

DISCUSSION

This is the first study in hypertensive patients complicated non-permanent AF in the Chinese population. Results of this study will inform the use of upstream therapies of AF.

TRIAL REGISTRATION

chictr.org, ChiCTR-TRC-12002642.

Atorvastatin Reduces the Incidence of Postoperative Atrial Fibrillation in Statin-Naive Patients Undergoing Isolated Heart Valve Surgery: A Double-Blind, Placebo-Controlled Randomized Trial

BACKGROUND

Atorvastatin has been demonstrated to reduce the incidence of postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery, but its effect on isolated heart valve surgery is unknown.

METHODS

In a randomized, double-blinded, placebo-controlled trial, 58 patients who underwent isolated heart valve surgery supported by on-pump cardiopulmonary bypass were randomly assigned to receive either placebo (n = 29) or 40 mg of atorvastatin once daily starting 3 days preoperatively and continuing within 5 days postoperatively (n = 29). A continuous monitoring tool and an electrocardiographic Holter monitoring were used for detecting the POAF (Clinical Trial Registration: www.clinicaltrials.gov; Unique Identifier: NTC02084069).

RESULTS

The patients' median age was 49 years, and 67% were female. In all, 6 (21%) and 13 (45%) cases of POAF were observed in the atorvastatin and placebo groups, respectively (P = .050). The duration of AF before re-establishment of sinus rhythm was significantly lower in the atorvastatin group than in the placebo group (median of 70 vs 132 minutes, P = .026). The lengths of intensive care unit and hospital stay were comparable between the groups. The increase in postoperative white blood cell count was significantly lower in the atorvastatin group than in the placebo group (median of 1.5 vs 2.3 × 10(3)/µL, respectively, P = .019). After adjustment, the atorvastatin treatment was associated with a decrease in the risk of developing POAF (odds ratio 0.122, 95% confidence interval 0.027-0.548, P = .006).

CONCLUSION

Perioperative treatment with 40 mg of atorvastatin is useful to decrease the incidence of POAF in the statin-naive patients undergoing isolated heart valve surgery.

Mapping and ablation of autonomic ganglia in prevention of postoperative atrial fibrillation in coronary surgery: MAAPPAFS atrial fibrillation randomized controlled pilot study

BACKGROUND

Postoperative atrial fibrillation (POAF) remains common after coronary artery bypass grafting (CABG). Limited efforts to intervene on cardiac autonomic ganglionic plexi (AGP) during surgery show mixed results. In this pilot study, we evaluated the safety and feasibility of map-guided ablation of AGPs during isolated CABG in the prevention of POAF.

METHODS

In this pilot study, patients undergoing isolated CABG were randomized into an intervention group (mapping and ablation of AGP [AGP+] group), and a control group (no mapping and ablation [AGP-] group). Using high-frequency stimulation, active AGPs were identified and ablated intraoperatively using radiofrequency. Continuous rhythm monitoring, serum electrolytes, postoperative medications, and postoperative complications were recorded until discharge.

RESULTS

Randomization of 47 patients (24 AGP+ and 23 AGP-) resulted in similar baseline characteristics, past medical history, and preoperative medication use. The intervention added a median of 14 minutes to the operative time. The incidence of POAF, mean time in POAF, and median length of stay in hospital were: AGP+ 21% vs AGP- 30%; AGP+ 298 minutes vs AGP- 514 minutes; AGP+ 5 days vs AGP- 6 days; respectively). Postoperative complications, medication use, and daily serum electrolyte profiles were similar in both groups.

CONCLUSIONS

This pilot study demonstrated the safety and feasibility of mapping and ablation of AGP during CABG with minimal added operative time. Results further suggest a potentially clinically significant effect on POAF. A multicentre trial is warranted.

Inflammation in new-onset atrial fibrillation after cardiac surgery: a systematic review

BACKGROUND

Postoperative new-onset atrial fibrillation (PNAF) is the most common complication following cardiac surgery. The pathogenesis of PNAF is multifactorial. The concept of the postoperative inflammatory response, as a potential underlying mechanism has been extensively studied. This review aims to provide a comprehensive summary of literature relevant to the association between the inflammatory response following cardiac surgery and PNAF.

DESIGN

MEDLINE, EMBASE and the Cochrane Central Register were systematically reviewed by two independent investigators for studies published between January 1980 and May 2012, in which an association between serum markers of inflammation and PNAF was evaluated, or the effect of drugs with anti-inflammatory properties on the risk of PNAF.

RESULTS

Sixty-three studies met selection criteria (39 observational and 24 randomized studies) including 27,363 patients. The mean incidence of PNAF after cardiac surgery was 25·5%. Elevated levels of various inflammatory mediators were associated with PNAF, and the most consistent association was found between white blood cell count and PNAF. Of the drugs with anti-inflammatory properties, statins gave the best protective effect against PNAF, followed by anti-oxidants, steroids and colchicine. Nonsteroidal anti-inflammatory drugs did not prevent PNAF significantly.

CONCLUSION

The postoperative inflammation response may play a role in the pathogenesis of PNAF. However, of the inflammation biomarkers, only elevated white blood cell count reliably predicts PNAF. Pre- and perioperative use of statins and several other drugs with anti-inflammatory properties reduce the incidence of PNAF.

Targeting inflammation and oxidative stress in atrial fibrillation: role of 3-hydroxy-3-methylglutaryl-coenzyme a reductase inhibition with statins

SIGNIFICANCE

Atrial fibrillation (AF) is a burgeoning health-care problem, and the currently available therapeutic armamentarium is barely efficient. Experimental and clinical evidence implicates inflammation and myocardial oxidative stress in the pathogenesis of AF.

RECENT ADVANCES

Local and systemic inflammation has been found to both precede and follow the new onset of AF, and NOX2-dependent generation of reactive oxygen species in human right atrial samples has been independently associated with the occurrence of AF in the postoperative period in patients undergoing cardiac surgery. Anti-inflammatory and antioxidant agents can prevent atrial electrical remodeling in animal models of atrial tachypacing and the new onset of AF after cardiac surgery, suggesting a causal relationship between inflammation/oxidative stress and the atrial substrate that supports AF.

CRITICAL ISSUES

Statin therapy, by redressing the myocardial nitroso-redox balance and reducing inflammation, has emerged as a potentially effective strategy for the prevention of AF. Evidence indicates that statins prevent AF-induced electrical remodeling in animal models of atrial tachypacing and may reduce the new onset of AF after cardiac surgery. However, whether statins have antiarrhythmic properties in humans has yet to be conclusively demonstrated, as data from randomized controlled trials specifically addressing the relevance of statin therapy for the primary and secondary prevention of AF remain scanty.

FUTURE DIRECTIONS

A better understanding of the mechanisms underpinning the putative antiarrhythmic effects of statins may afford tailoring AF treatment to specific clinical settings and patient's subgroups. Large-scale randomized clinical trials are needed to support the indication of statin therapy solely on the basis of AF prevention.

Rac1-mediated effects of HMG-CoA reductase inhibitors (statins) in cardiovascular disease

SIGNIFICANCE

HMG-CoA reductase inhibitors (statins) lower serum cholesterol concentrations and are beneficial in the primary and secondary prevention of coronary heart disease. The positive clinical effects have only partially been reproduced with other lipid-lowering interventions suggesting potential statin effects in addition to cholesterol lowering. In experimental models, direct beneficial cardiovascular effects that are mediated by the inhibition of isoprenoids have been documented, which serve as lipid attachments for intracellular signaling molecules such as small Rho guanosine triphosphate-binding proteins, whose membrane localization and function are dependent on isoprenylation.

RECENT ADVANCES

Rac1 GTPase is an established master regulator of cell motility through the cortical actin reorganization and of reactive oxygen species generation through the regulation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity.

CRITICAL ISSUES

Observations in cells, animals, and humans have implicated the activation of Rac1 GTPase as a key component of cardiovascular pathologies, including the endothelial dysfunction, cardiac hypertrophy and fibrosis, atrial fibrillation, stroke, hypertension, and chronic kidney disease. However, the underlying signal transduction remains incompletely understood.

FUTURE DIRECTIONS

Based on the recent advance made in Rac1 research in the cardiovascular system by using mouse models with transgenic overexpression of activated Rac1 or conditional knockout, as well as Rac1-specific small molecule inhibitor NSC 23766, the improved understanding of the Rac1-mediated effects statins may help to identify novel therapeutic targets and strategies.

[Upstream therapy for atrial fibrillation]

In recent years a tremendous amount has been learned about the pathophysiology of atrial fibrillation (AF) which induces electrophysiological changes in the right and left atrium. Besides calcium-dependent tissue changes which are induced by activation of proteases and phosphatases, such as calpain and calcineurin, concomitant cardiac diseases activate the atrial angiotensin II system. Experiments have shown positive effects of statins in AF models. In contrast, clinical studies have provided heterogeneous results. Of note, several studies have shown that therapy with angiotensin II receptor blockers or statins does not influence the recurrence of AF.

Comparison of rosuvastatin versus atorvastatin for preventing postoperative atrial fibrillation

BACKGROUND

Postoperative atrial fibrillation (AF) following cardiac surgery is associated with an increased risk of stroke, prolonged hospitalization, and increased costs. Statin therapy is associated with a lower incidence of postoperative AF. We aimed to compare the preventive effects of rosuvastatin and atorvastatin on postoperative AF.

METHODS

This study included 168 patients undergoing elective cardiac surgery with cardiopulmonary bypass. Patients were divided into 2 groups according to treatment of statin. Group 1 (n = 96) was patients receiving atorvastatin, and group 2 (n = 72) was patients receiving rosuvastatin. Postoperative electrocardiographs (ECGs) and telemetry strips were examined for AF within postoperative period during hospitalization.

RESULTS

The incidences of postoperative AF were 17.9% (n = 17) in group 1 and 22.2% (n = 16) in group 2 (P = .48). Left ventricular end-diastolic diameter (LVEDD) and ejection fraction (EF) were not different between groups. Incidence of diabetes, hypertension, hyperlipidemia, smoking, myocardial infarction in past medical history, family history of atherosclerosis, male sex, drug use, and perioperative features were similar between groups.

CONCLUSIONS

The present study revealed that preoperative rosuvastatin or atorvastatin treatment did not have a different effect in preventing postoperative AF.

Meta-analysis of patients taking statins before revascularization and aortic valve surgery

Statin intake before cardiac surgery is associated with favorable outcomes. We sought to analyze the evidence for statin pretreatment before isolated coronary artery bypass graft surgery and aortic valve replacement surgery. In this meta-analysis, we demonstrate beneficial results for the endpoints mortality, stroke, atrial fibrillation, and length of stay in hospital in 36,053 statin-pretreated coronary artery bypass graft surgery patients compared with control subjects retrieved from 32 studies, but fail to detect relevant advantages through preoperative statin therapy for 3,091 patients undergoing aortic valve replacement from four trials. Strict adherence to guidelines recommending statin treatment before CABG surgery is therefore mandatory.

Oxidative stress in atrial fibrillation: an emerging role of NADPH oxidase

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Patients with AF have up to seven-fold higher risk of suffering from ischemic stroke. Better understanding of etiologies of AF and its thromboembolic complications are required for improved patient care, as current anti-arrhythmic therapies have limited efficacy and off target effects. Accumulating evidence has implicated a potential role of oxidative stress in the pathogenesis of AF. Excessive production of reactive oxygen species (ROS) is likely involved in the structural and electrical remodeling of the heart, contributing to fibrosis and thrombosis. In particular, NADPH oxidase (NOX) has emerged as a potential enzymatic source for ROS production in AF based on growing evidence from clinical and animal studies. Indeed, NOX can be activated by known upstream triggers of AF such as angiotensin II and atrial stretch. In addition, treatments such as statins, antioxidants, ACEI or AT1RB have been shown to prevent post-operative AF; among which ACEI/AT1RB and statins can attenuate NOX activity. On the other hand, detailed molecular mechanisms by which specific NOX isoform(s) are involved in the pathogenesis of AF and the extent to which activation of NOX plays a causal role in AF development remains to be determined. The current review discusses causes and consequences of oxidative stress in AF with a special focus on the emerging role of NOX pathways.

Preoperative statin therapy in cardiac surgery: a meta-analysis of 90,000 patients

The objective of this systematic literature review with meta-analysis was to determine the strength of evidence for a preoperative statin on the reduction of adverse postoperative outcomes in patients undergoing cardiac surgery. Randomized controlled (RCT) and observational trials were searched in online databases that reported about the effects of preoperative statin therapy on major adverse clinical outcomes after cardiac surgery. Analysed outcomes included early all-cause mortality, myocardial infarction, atrial fibrillation (AF), stroke and renal failure using a priori-defined criteria. Effect estimates were calculated and are given as odds ratio (OR) with 95% confidence intervals (95% CI) using fixed- or random-effect models. Literature search of all major databases retrieved 2371 studies. After screening, a total of 54 trials were identified (12 RCT, 42 observational) that reported outcomes of 91 491 cardiac surgery patients with (n = 46 614; 51%) or without (n = 44 877; 49%) preoperative statin therapy. Preoperative statin use resulted in a 0.9% absolute risk (2.6 vs 3.5%) and a 31% odds reduction for early all-cause mortality (OR 0.69; 95% CI 0.59-0.81; P < 0.0001). In addition, statin treatment before surgery was associated with a substantial reduction (P < 0.01) in the postoperative end-points AF (OR 0.71; 95% CI 0.61-0.82), new-onset AF (OR 0.68; 95% CI 0.54-0.85), stroke (OR 0.83; 95% CI 0.74-0.93), stay on intensive care unit (weighted mean difference [WMD] -0.14; 95% CI -0.23 to -0.03; P < 0.01) and in-hospital stay (WMD -0.57; 95% CI -0.76 to -0.38; P < 0.01). No statistical differences were found between groups with regard to myocardial infarction or renal failure. In conclusion, the current systematic review strengthens the evidence that preoperative statin therapy extends substantial clinical benefit to early postoperative outcomes in cardiac surgery patients.

Safety and efficacy of an ultrashort-acting β1-blocker on left ventricular dysfunction

Landiolol hydrochloride, an ultrashort-acting β1-selective blocker, is a highly regulated drug. This study evaluated the safety and efficacy of this drug for cases of coronary artery bypass grafting (CABG) with left ventricular dysfunction. Between September 2006 and August 2009, 32 patients with a left ventricular ejection fraction of <40% underwent CABG. Two groups of patients, a group administered landiolol hydrochloride and a control group not administered this drug, were compared. The administration of landiolol hydrochloride was initiated at 1 μg/kg per minute (γ) after cardiopulmonary bypass in on-pump cases and after completion of all the distal anastomoses in off-pump cases. We observed no significant differences between the groups with respect to preoperative patient background or incidences of complications, except for postoperative atrial fibrillation. The heart rate decreased significantly 30 minutes after landiolol hydrochloride administration, but no change was observed in arterial pressure. No change was observed in other parameters; the hemodynamics were stable. The occurrence of atrial fibrillation during the intensive care unit stay (during landiolol hydrochloride administration) was significantly lower in the administration group. The difference remained significant after multiple logistic regression analysis; landiolol hydrochloride was the sole inhibitory factor.

Rosuvastatin in patients with arterial hypertension and dyslipidemia: effects on microcirculation and pulse wave parameters

Aim. To investigate the parameters of pulse wave contour analysis (PWCA) and microcirculation (MC) in patients with arterial hypertension (AH), dyslipidemia (DLP), and high cardiovascular risk levels (SCORE >5%); to compare the dynamics of these parameters during the treatment with rosuvastatin or atorvastatin. Material and methods. The study included 82 patients (mean age 53±10 years) with the high-risk AH (SCORE levels >5%), DLP, and no strict contraindications to statins. All patients were randomised into two comparable groups: Group I (n=40; mean age 51±10 years), receiving atorvastatin and standard AH treatment; and Group II (n=42; mean age 52±10 years), receiving rosuvastatin and standard AH treatment. At baseline and after 5 weeks, all patients underwent the MC assessment (conjunctival biomicroscopy) and PWCA (AngioScan-01). The following parameters were assessed: stiffness index (SI), reflection index (RI), augmentation index (AIx), and increased pulse wave amplitude (PWA). Results. In the atorvastatin group, mean SI values were 5,87±2,05 m/s, RI values 35,64±19,98%, mean AIx values for heart rate of 75 beats per minute (AIx75) 41,21±14,56%, and mean central blood pressure (BP, Spa) levels 144,35±22,31 mm Hg. In the rosuvastatin group, the respective values were 5,01±2,56 m/s (SI), 37,01±14,56% (RI), 41,23±14,35% (AIx75), and 148,98±7,89 mm Hg (BP, Spa). All participants demonstrated PW Types A and B, as a marker of increased arterial stiffness, and positive AIx and AIx75 values. The treatment with atorvastatin and rosuvastatin was associated with a significant reduction in ∆SI (-0,87 and -0,89 m/s, respectively). Both groups demonstrated a non-significant reduction in ∆RI (-7,89 and -7,21%, respectively) and ∆AIx (-1,88 and -1,92%, respectively). PWA increased by 1,82±0,62 times in the atorvastatin group and by 1,95±0,81 times in the rosuvastatin group. At baseline, both groups demonstrated disturbed conjunctival MC (arterio-venular coefficient 1:3, stasis, and Stage III erythrocyte aggregation). Atorvastatin and rosuvastatin treatment was linked to a regression in the last two parameters, which could be explained by the improved vascular wall elasticity. Conclusion. In high-risk patients with AH, the PWCA data suggested an increase in arterial stiffness, which was combined with conjunctival MC disturbances. Statin therapy improved not only blood lipid levels, but also MC, vascular stiffness, and endothelial function parameters, which was more pronounced in the rosuvastatin group.

The role of statin therapy in the prevention of atrial fibrillation: a meta-analysis of randomized controlled trials

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Atrial fibrillation (AF) is the most common clinically significant cardiac arrhythmia, and AF is associated with relatively higher all-cause mortality in both men and women. However, there are limited treatment options for AF. Statins are hypothesized to have a benefit against arrhythmias in addition to well-established secondary prevention benefit for atherosclerotic coronary artery disease, yet the data are inconsistent

WHAT THIS STUDY ADDS

Statin therapy was significantly associated with a decreased risk of incidence or recurrence of AF. The benefit of statin therapy seemed more markedly in secondary prevention than primary prevention. These results provided some evidence for the benefit of statins beyond their lipid-lowering activity

AIMS

The use of statins has been suggested to protect against atrial fibrillation (AF) in some clinical observational and experimental studies but has remained inadequately explored. This study was designed to examine whether statins can reduce the risk of AF.

METHODS

Meta-analysis of randomized, controlled trials with use of statins on incidence or recurrence of AF was performed.

RESULTS

Twenty studies with 23,577 patients were included in the analysis. Seven studies investigated the use of statins in patients with AF, 11 studies investigated the primary prevention of statins in patients without AF, and two studies investigated mixed populations of patients. The incidence or recurrence of AF occurred in 1543 patients. Overall, statin therapy was significantly associated with a decreased risk of AF compared with control (odds ratio 0.49, 95% confidence interval 0.37-0.65; P < 0.00001). A beneficial effect was found in the atorvastatin subgroup and the simvastatin subgroup, but not in the pravastatin subgroup or the rosuvastatin subgroup. The benefit of statin therapy appeared to be more pronounced in secondary prevention (odds ratio 0.34, 95% confidence interval 0.18-0.64; P < 0.0008) than in primary prevention (odds ratio 0.54, 95% confidence interval 0.40-0.74; P < 0.0001).

CONCLUSIONS

Statin therapy was significantly associated with a decreased risk of incidence or recurrence of AF. Heterogeneity was explained by differences in statin types, patient populations and surgery types. The benefit of statin therapy seemed more pronounced in secondary than in primary prevention.

Primary Prevention of Atrial Fibrillation where are we in 2012?

Drugs to alter or delay myocardial remodelling associated with heart failure, hypertension, or inflammation in the post-operative setting, may prevent the development of atrial fibrillation. Current experimental and clinical evidences support specific treatments for defined patient population (i.e. ACE-inhibitors and ARB for chronic heart failure and hypertension expecially with LV hypertrophy; statins, corticosteroids and possibly colchicine after cardiac surgery).

Intravenous magnesium prevents atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 7 double-blind, placebo-controlled, randomized clinical trials

Background

Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG.

Methods

Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity.

Results

Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; P = 0.001; with no heterogeneity between trials (heterogeneity P = 0.8, I² = 0%)).

Conclusions

This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.

Management of postoperative atrial fibrillation

The impact of postoperative atrial fibrillation (PAF) on patient outcomes has prompted intense investigation into the optimal methods for prevention and treatment of this complication. In the prevention of PAF, β-blockers and amiodarone are particularly effective and are recommended by guidelines. However, their use requires caution due to the possibility of drug-related adverse effects. Aside from these risks, perioperative prophylactic treatment with statins seems to be effective for preventing PAF and is associated with a low incidence of adverse effects. PAF can be treated by rhythm control, heart-rate control, and antithrombotic therapy. For the purpose of heart rate control, β-blockers, calcium-channel antagonists, and amiodarone are used. In patients with unstable hemodynamics, cardioversion may be performed for rhythm control. Antithrombotic therapy is used in addition to heart-rate maintenance therapy in cases of PAF >48-h duration or in cases with a history of cerebrovascular thromboembolism. Anticoagulation is the first choice for antithrombotic therapy, and anticoagulation management should focus on maintaining international normalized ratio (INRs) in the 2.0–3.0 range in patients <75 years of age, whereas prothrombin-time INR should be controlled to the 1.6–2.6 range in patients ≥75 years of age. In the future, dabigatran could be used for perioperative management of PAF, because it does not require regular monitoring and has a quick onset of action with short serum half-life. Preventing PAF is an important goal and requires specific perioperative management as well as other approaches. PAF is also associated with lifestyle-related diseases, which emphasizes the ongoing need for appropriate lifestyle management in individual patients.

Effects of rosuvastatin on serum asymmetric dimethylarginine levels and atrial structural remodeling in atrial fibrillation dogs

BACKGROUND

Circulating asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase inhibitor, is increased in atrial fibrillation (AF). The purpose of this study was to investigate the effects of rosuvastatin on serum ADMA levels and atrial structural remodeling in AF dogs induced by chronic rapid atrial pacing.

METHODS

Twenty dogs were randomly divided into the sham-operated (n=6), control (n=7), or rosuvastatin (n=7) groups. Sustained AF was induced by rapid pacing of the right atrium at 400 beats per minute for 6 weeks. Rosuvastatin was administered orally (1 mg/kg d) for 3 days before rapid pacing and was continued for 6 weeks. Transthoracic and transesophageal echocardiography were performed to detect left atrial structure and function. Serum levels of nitric oxide and ADMA were measured. Interstitial fibrosis and cardiomyocyte apoptosis in the atria were also identified.

RESULTS

After 6 weeks, compared with the control group, dramatic smaller left atrium and left atrial appendage volumes and higher atrial contractile function were observed in the rosuvastatin group. Serum nitric oxide concentration was increased, whereas ADMA was decreased in the rosuvastatin group compared with the control group. The percentages of interstitial fibrosis and atrial apoptosis in the control group were significantly higher than those in the sham-operated group, and rosuvastatin attenuated these changes induced by atrial rapid pacing.

CONCLUSION

A short course of rosuvastatin treatment decreased apoptosis and prevented atrial structural remodeling in association with a decrease in ADMA levels in AF dogs.