Preoperative high-dose atorvastatin for prevention of atrial fibrillation after cardiac surgery: a randomized controlled trial

Preoperative statin therapy for adults undergoing cardiac surgery

BACKGROUND

Despite significant advances in surgical techniques and perioperative care, people undertaking cardiac surgery due to cardiovascular disease are more prone to the development of postoperative adverse events. Statins (5-hydroxy-3-methylglutaryl-co-enzyme A (HMG-CoA) reductase inhibitors) are well-known for their anti-inflammatory and antioxidant effects and are established for primary and secondary prevention of coronary artery disease. In addition, statins are thought to have clinical benefits in perioperative outcomes in people undergoing cardiac surgery. This review is an update of a review that was first published in 2012 and updated in 2015.

OBJECTIVES

To evaluate the benefits and harms of preoperative statin therapy in adults undergoing cardiac surgery compared to standard of care or placebo.

SEARCH METHODS

We performed a search of the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 9, 2023), Ovid MEDLINE (1980 to 14 September 2023), and Ovid Embase (1980 to 2023 (week 36)). We applied no language restrictions.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing any statin treatment before cardiac surgery, for any given duration and dose, versus no preoperative statin therapy (standard of care) or placebo. We excluded trials without a registered trial protocol and trials without approval by an institutional ethics committee.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology. Primary outcomes were short-term mortality and major adverse cardiovascular events. Secondary outcomes were myocardial infarction, atrial fibrillation, stroke, renal failure, length of intensive care unit (ICU) stay, length of hospital stay and adverse effects related to statin therapy. We reported effect measures as risk ratios (RRs) or mean differences (MDs) with corresponding 95% confidence intervals (CIs). We used the RoB 1 tool to assess the risk of bias in included trials, and GRADE to assess the certainty of the evidence.

MAIN RESULTS

We identified eight RCTs (five new to this review) including 5592 participants. Pooled analysis showed that statin treatment before surgery may result in little to no difference in the risk of postoperative short-term mortality (RR 1.36, 95% CI 0.72 to 2.59; I2 = 0%; 6 RCTs, 5260 participants; low-certainty evidence; note 2 RCTs reported 0 events in both groups so RR calculated from 4 RCTs with 5143 participants). We are very uncertain about the effect of statins on major adverse cardiovascular events (RR 0.93, 95% CI 0.77 to 1.13; 1 RCT, 2406 participants; very low-certainty evidence). Statins probably result in little to no difference in myocardial infarction (RR 0.88, 95% CI 0.73 to 1.06; I2 = 0%; 5 RCTs, 4645 participants; moderate-certainty evidence), may result in little to no difference in atrial fibrillation (RR 0.87, 95% CI 0.72 to 1.05; I2 = 60%; 8 RCTs, 5592 participants; low-certainty evidence), and may result in little to no difference in stroke (RR 1.47, 95% CI 0.90 to 2.40; I2 = 0%; 4 RCTs, 5143 participants; low-certainty evidence). We are very uncertain about the effect of statins on renal failure (RR 1.04, 95% CI 0.80 to 1.34; I2 = 57%; 4 RCTs, 4728 participants; very low-certainty evidence). Additionally, statins probably result in little to no difference in length of ICU stay (MD 1.40 hours, 95% CI -1.62 to 4.41; I2 = 43%; 3 RCTs, 4528 participants; moderate-certainty evidence) and overall hospital stay (MD -0.31 days, 95% CI -0.64 to 0.03; I2 = 84%; 5 RCTs, 4788 participants; moderate-certainty evidence). No study had any individual risk of bias domain classified as high. However, two studies were at high risk of bias overall given the classification of unclear risk of bias in three domains.

AUTHORS' CONCLUSIONS

In this updated Cochrane review, we found no evidence that statin use in the perioperative period of elective cardiac surgery was associated with any clinical benefit or worsening, when compared with placebo or standard of care. Compared with placebo or standard of care, statin use probably results in little to no difference in MIs, length of ICU stay and overall hospital stay; and may make little to no difference to mortality, atrial fibrillation and stroke. We are very uncertain about the effects of statins on major harmful cardiac events and renal failure. The certainty of the evidence validating this finding varied from moderate to very low, depending on the outcome. Future trials should focus on assessing the impact of statin therapy on mortality and major adverse cardiovascular events.

Perioperative Statin Use May Reduce Postoperative Arrhythmia Rates After Total Joint Arthroplasty

BACKGROUND

Postoperative arrhythmias are associated with increased morbidity and mortality in total joint arthroplasty (TJA) patients. HMG-CoA (3-hydroxy-3-methyl-glutaryl-CoA) reductase inhibitors (statins) decrease atrial fibrillation rates after cardiac surgery, but it is unknown if this cardioprotective effect is maintained after joint reconstruction surgery. We aim to determine if perioperative statin use decreases the incidence of 90-day postoperative arrhythmias in patients undergoing primary TJA.

METHODS

We performed a single-center retrospective cohort study in which 231 primary TJA patients (109 hips, 122 knees) received simvastatin 80 mg daily during their hospitalization as part of a single surgeon's standard postoperative protocol. This cohort was matched to 966 primary TJA patients (387 hips and 579 knees) that did not receive simvastatin. New-onset arrhythmias (bradycardia, atrial fibrillation/tachycardia/flutter, paroxysmal supraventricular tachycardia, and ventricular tachycardia) and complications (readmissions, thromboembolism, infection, and dislocation) within 90 days of the procedure were documented. Categorical variables were analyzed using Fisher's exact tests. Our study was powered to detect a 3% difference in arrhythmia rates.

RESULTS

Within 90 days postoperatively, arrhythmias occurred in 1 patient (0.4%) who received a perioperative statin, 39 patients (4.0%) who did not receive statins (P = .003), and 24 patients (4.2%) who were on outpatient statins (P = .005). This is 10-fold reduction in the relative risk of developing a postoperative arrhythmia within 90 days of arthroplasty and an absolute risk reduction of 3.6%.

CONCLUSION

Treating as few as 28 patients with perioperative simvastatin prevents one new cardiac arrhythmia within 90 days in statin-naïve patients undergoing TJA.

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.

Evaluation of high-dose atorvastatin pretreatment influence in patients preconditioning of post coronary artery bypass graft surgery: A prospective triple blind randomized clinical trial

Context

Atorvastatin is considered as lipid reductive drugs with anti-inflammatory and pleotherapic effects in coronary artery bypass graph (CABG).

Aim

This study is conducted to evaluate the effects of atorvastatin in CABG.

Setting and Design

Patients with a coronary bypass graph procedure in Nemazee hospital in Shiraz were divided into two 50-groups receiving high-dose (80 mg) and low-dose (20 mg) atorvastatin.

Materials and Methods

Troponin I, creatinine kinase-MB (CK-MB), atrial fibrillation (AF) after CABG, duration of mechanical ventilation, inotrope duration of consumption, blood sugar profile, liver and renal function, death during 30 days of CABG, MACE (major advance cardiac events) during admission in ICU, and 1 month follow up were surveyed.

Statistical Analysis

Collected data were analyzed by independent and paired t-test and Chi square.

Results

AST was increased, ALT, ALK-P after CABG were decreased, and urine volume in the second day of admission in ICU was increased in the high-dose group. There was an increase and following decrease in blood sugar of patients in the high-dose after CABG. An inflammatory marker after CABG was raised in both groups, ck-mb had an increase, and then followed by a reduction. Troporin had no significant differences between groups. Patients with high-dose atorvastatin had better glomerular filtration rate and renal performance. Along with decreasing AF in the case group, hemodynamics' disorder reduced and there was less bleeding.

Conclusion

According to the above, it seems that a short-time prescription of high dose of atorvastatin in CABG can lead to better renal function, decreasing of arrhythmia and AF.

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.

Atorvastatin dose-dependently promotes mouse lung repair after emphysema induced by elastase

Emphysema results in a proteinase - antiproteinase imbalance, inflammation and oxidative stress. Our objective was to investigate whether atorvastatin could repair mouse lungs after elastase-induced emphysema. Vehicle (50 μL) or porcine pancreatic elastase (PPE) was administered on day 1, 3, 5 and 7 at 0.6 U intranasally. Male mice were divided into a control group (sham), PPE 32d (sacrificed 24 h after 32 days), PPE 64d (sacrificed 24 h after 64 days), and atorvastatin 1, 5 and 20 mg treated from day 33 until day 64 and sacrificed 24 h later (A1 mg, A5 mg and A20 mg, respectively). Treatment with atorvastatin was performed via inhalation for 10 min once a day. We observed that emphysema at day 32 was similar to emphysema at day 64. The mean airspace chord length (Lm) indicated a recovery of pulmonary morphology in groups A5 mg and A20 mg, as well as recovery of collagen and elastic fibers in comparison to the PPE group. Bronchoalveolar lavage fluid (BALF) leukocytes were reduced in all atorvastatin-treated groups. However, tissue macrophages were reduced only in the A20 mg group compared with the PPE group, while tissue neutrophils were reduced in the A5 mg and A20 mg groups. The redox balance was restored mainly in the A20 mg group compared with the PPE group. Finally, atorvastatin at doses of 5 and 20 mg reduced nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and matrix metalloproteinase-12 (MMP-12) compared with the PPE group. In conclusion, atorvastatin was able to induce lung tissue repair in emphysematous mice.

Efficacy of Different Perioperative Statin Regimens on Protection Against Post-Coronary Artery Bypass Grafting Major Adverse Cardiac and Cerebral Events

OBJECTIVES

Comparing different perioperative statin regimens for the prevention of post-coronary artery bypass grafting adverse events.

DESIGN

A randomized, prospective study.

SETTING

Cardiothoracic surgical units in a government hospital.

PARTICIPANTS

The study comprised 94 patients scheduled for elective, isolated on- or off- pump coronary artery bypass grafting.

INTERVENTIONS

Patients were assigned randomly to 1 of the following 3 treatment groups: group I (80 mg of atorvastatin/day for 2 days preoperatively), group II (40 mg of atorvastatin/day for 5-9 days preoperatively), or group III (80 mg of atorvastatin/day for 5-9 days preoperatively). The same preoperative doses were restarted postoperatively and continued for 1 month.

MEASUREMENTS AND MAIN RESULTS

Cardiac troponin I, creatine kinase, and C-reactive protein (CRP) levels were assayed preoperatively; at 8, 24, and 48 hours postoperatively; and at discharge. CRP levels at 24 hours (p = 0.045) and 48 hours (p = 0.009) were significantly lower in group III compared with the other 2 groups. However, troponin I levels at 8 hours (p = 0.011) and 48 hours (p = 0.025) after surgery were significantly lower in group II compared with group III. The incidence of postoperative major adverse cardiac and cerebrovascular events was assessed, and there was no significant difference among the 3 groups.

CONCLUSION

The 3 regimens did not result in any significant difference in outcomes, but only simple trends. The higher-dose regimen resulted in a significant reduction in the CRP level. Thus, more studies are needed to confirm the benefit of higher-dose statins for the protection from post-coronary artery bypass grafting adverse events.

WITHDRAWN: Preoperative statin therapy for patients undergoing cardiac surgery

This review has been withdrawn as authors are unable to complete the updating process.

The editorial group responsible for this previously published document have withdrawn it from publication.

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).

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.

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.

Outcome Reporting in Cardiac Surgery Trials: Systematic Review and Critical Appraisal

Background

There is currently no accepted standard for reporting outcomes following cardiac surgery. The objective of this paper was to systematically review the literature to evaluate the current use and definition of perioperative outcomes reported in cardiac surgery trials.

Methods and Results

We reviewed 5 prominent medical and surgical journals on Medline from January 1, 2010, to June 30, 2014, for randomized controlled trials involving coronary artery bypass grafting and/or valve surgery. We identified 34 trials meeting inclusion criteria. Sample sizes ranged from 57 to 4752 participants (median 351). Composite end points were used as a primary outcome in 56% (n=19) of the randomized controlled trials and as a secondary outcome in 12% (n=4). There were 14 different composite end points. Mortality at any time (all-cause and/or cardiovascular) was reported as an individual end point or as part of a combined end point in 82% (n=28), myocardial infarction was reported in 68% (n=23), and bleeding was reported in 24% (n=8). Patient-centered outcomes, such as quality of life and functional classification, were reported in 29% (n=10). Definition of clinical events such as myocardial infarction, stroke, renal failure, and bleeding varied considerably among trials, particularly for postoperative myocardial infarction and bleeding, for which 8 different definitions were used for each.

Conclusions

Outcome reporting in the cardiac surgery literature is heterogeneous, and efforts should be made to standardize the outcomes reported and the definitions used to ascertain them. The development of standardizing outcome reporting is an essential step toward strengthening the process of evidence-based care in cardiac surgery.

Preoperative statin therapy for patients undergoing cardiac surgery

BACKGROUND

Patients referred to cardiac surgery for cardiovascular disease are at significant risk for the development of major postoperative adverse events despite significant advances in surgical techniques and perioperative care. Statins (5-hydroxy-3-methylglutaryl-co-enzyme A (HMG-CoA) reductase inhibitors) have gained a pivotal role in the primary and secondary prevention of coronary artery disease and are thought to improve perioperative outcomes in patients undergoing cardiac surgery. This review is an updated version of a review that was first published in 2012.

OBJECTIVES

To determine the effectiveness of preoperative statin therapy in patients undergoing cardiac surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 11), MEDLINE (1950 to November 2013 Week 3), EMBASE (1980 to 3 December 2013 (Week 48)) and the metaRegister of Controlled Trials. Additionally, we searched ongoing trials through the National Research Register, the ClinicalTrials.gov registry and grey literature. We screened online conference indices from relevant scientific meetings (2006 to 2014) to look for eligible trials. We applied no language restrictions.

SELECTION CRITERIA

All randomised controlled trials comparing any statin treatment before cardiac surgery, for any given duration and dose, versus no preoperative statin therapy (standard of care) or placebo.

DATA COLLECTION AND ANALYSIS

Two review authors evaluated trial quality and extracted data from titles and abstracts identified by electronic database searches according to predefined criteria. Accordingly, we retrieved full-text articles of potentially relevant studies that met the inclusion criteria to assess definitive eligibility for inclusion. We reported effect measures as odds ratios (ORs) or weighted mean differences (WMDs) with 95% confidence intervals (95% CIs).

MAIN RESULTS

We identified 17 randomised controlled studies including a total of 2138 participants undergoing on-pump or off-pump cardiac surgical procedures, and added to this review six studies with 1154 additional participants. Pooled analysis showed that statin treatment before surgery reduced the incidence of postoperative atrial fibrillation (AF) (OR 0.54, 95% CI 0.43 to 0.67; P value < 0.01; 12 studies, 1765 participants) but failed to influence short-term mortality (OR 1.80, 95% CI 0.38 to 8.54; P value = 0.46; two studies, 300 participants) or postoperative stroke (OR 0.70, 95% CI 0.14 to 3.63; P value = 0.67; two studies, 264 participants). In addition, statin therapy was associated with a shorter stay for patients on the intensive care unit (ICU) (WMD -3.19 hours, 95% CI -5.41 to -0.98; nine studies, 721 participants) and in the hospital (WMD -0.48 days, 95% CI -0.78 to -0.19; 11 studies, 1137 participants) when significant heterogeneity was observed. Results showed no reduction in myocardial infarction (OR 0.48, 95% CI 0.21 to 1.13; seven studies, 901 participants) or renal failure (OR 0.57, 95% CI 0.30 to 1.10; five studies, 467 participants) and were not affected by subgroup analysis. Trials investigating this safety endpoint reported no major or minor perioperative side effects of statins.

AUTHORS' CONCLUSIONS

Preoperative statin therapy reduces the odds of postoperative atrial fibrillation (AF) and shortens the patient's stay on the ICU and in the hospital. Statin pretreatment had no influence on perioperative mortality, stroke, myocardial infarction or renal failure, but only two of all included studies assessed mortality. As analysed studies included mainly individuals undergoing myocardial revascularisation, results cannot be extrapolated to patients undergoing other cardiac procedures such as heart valve or aortic surgery.

Meta-analysis of 12 trials evaluating the effects of statins on decreasing atrial fibrillation after coronary artery bypass grafting

Atrial fibrillation (AF) is a common arrhythmia encountered after coronary artery bypass graft surgery (CABG) and is associated with poor outcomes. The purpose of this study was to examine whether initiation of statins before CABG reduces the risk of postoperative AF. We searched for clinical trials that randomized patients who underwent CABG to preoperative statin therapy versus placebo. We required that the trial reported the incidence of postoperative AF. Random-effects summary odds ratio (OR) were constructed. Sensitivity analysis for the trials that reported AF as a primary outcome along with subgroup analyses according to the different statins used was also conducted. Twelve trials with 2,980 patients met our inclusion criteria. Atorvastatin was tested in 8 trials, whereas rosuvastatin was studied in 2 studies. Statins were associated with a lower risk of postoperative AF (OR 0.42, 95% confidence interval [CI] 0.27 to 0.66, p <0.0001). There was benefit with atorvastatin (OR 0.35, 95% CI 0.25 to 0.50, p <0.0001) but not rosuvastatin (OR 0.69, 95% CI 0.28 to 1.71, p = 0.42). On sensitivity analysis limited to trials that reported AF as a primary outcome, the risk of postoperative AF was still reduced with statins (OR 0.40, 95% CI 0.25 to 0.90, p = 0.02). The mean duration of the hospital stay was significantly lower in the statin group: 8.5 ± 1.8 days versus 9.1 ± 2.2 days (p <0.0001). Statin therapy, particularly atorvastatin, before CABG was associated with a reduction in the risk of postoperative AF.

HMG CoA reductase inhibitors (statins) for preventing acute kidney injury after surgical procedures requiring cardiac bypass

BACKGROUND

Acute kidney injury (AKI) is common in patients undergoing cardiac surgery among whom it is associated with poor outcomes, prolonged hospital stays and increased mortality. Statin drugs can produce more than one effect independent of their lipid lowering effect, and may improve kidney injury through inhibition of postoperative inflammatory responses.

OBJECTIVES

This review aimed to look at the evidence supporting the benefits of perioperative statins for AKI prevention in hospitalised adults after surgery who require cardiac bypass. The main objectives were to 1) determine whether use of statins was associated with preventing AKI development; 2) determine whether use of statins was associated with reductions in in-hospital mortality; 3) determine whether use of statins was associated with reduced need for RRT; and 4) determine any adverse effects associated with the use of statins.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 13 January 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared administration of statin therapy with placebo or standard clinical care in adult patients undergoing surgery requiring cardiopulmonary bypass and reporting AKI, serum creatinine (SCr) or need for renal replacement therapy (RRT) as an outcome were eligible for inclusion. All forms and dosages of statins in conjunction with any duration of pre-operative therapy were considered for inclusion in this review.

DATA COLLECTION AND ANALYSIS

All authors extracted data independently and assessments were cross-checked by a second author. Likewise, assessment of study risk of bias was initially conducted by one author and then by a second author to ensure accuracy. Disagreements were arbitrated among authors until consensus was reached. Authors from two of the included studies provided additional data surrounding post-operative SCr as well as need for RRT. Meta-analyses were used to assess the outcomes of AKI, SCr and mortality rate. Data for the outcomes of RRT and adverse effects were not pooled. Adverse effects taken into account were those reported by the authors of included studies.

MAIN RESULTS

We included seven studies (662 participants) in this review. All except one study was assessed as being at high risk of bias. Three studies assessed atorvastatin, three assessed simvastatin and one investigated rosuvastatin. All studies collected data during the immediate perioperative period only; data collection to hospital discharge and postoperative biochemical data collection ranged from 24 hours to 7 days. Overall, pre-operative statin treatment was not associated with a reduction in postoperative AKI, need for RRT, or mortality. Only two studies (195 participants) reported postoperative SCr level. In those studies, patients allocated to receive statins had lower postoperative SCr concentrations compared with those allocated to no drug treatment/placebo (MD 21.2 µmol/L, 95% CI -31.1 to -11.1). Adverse effects were adequately reported in only one study; no difference was found between the statin group compared to placebo.

AUTHORS' CONCLUSIONS

Analysis of currently available data did not suggest that preoperative statin use is associated with decreased incidence of AKI in adults after surgery who required cardiac bypass. Although a significant reduction in SCr was seen postoperatively in people treated with statins, this result was driven by results from a single study, where SCr was considered as a secondary outcome. The results of the meta-analysis should be interpreted with caution; few studies were included in subgroup analyses, and significant differences in methodology exist among the included studies. Large high quality RCTs are required to establish the safety and efficacy of statins to prevent AKI after cardiac surgery.

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

Background

A number of clinical and experimental studies have investigated the effect of atorvastatin on atrial fibrillation (AF), but the results are equivocal. This meta-analysis was performed to evaluate whether atorvastatin can reduce the risk of AF in different populations.

Methods

We searched PubMed, EMBASE and the Cochrane Database for all published studies that examined the effect of atorvastatin therapy on AF up to April 2014. A random effects model was used when there was substantial heterogeneity and a fixed effects model when there was negligible heterogeneity.

Results

Eighteen published studies including 9952 patients with sinus rhythm were identified for inclusion in the analysis. Ten studies investigated primary prevention of AF by atorvastatin in patients without AF, seven studies investigated secondary prevention of atorvastatin in patients with AF, and one study investigated mixed populations of patients. Overall, atorvastatin was associated with a decreased risk of AF (odds ratio (OR) 0.51, 95% confidence interval (CI) 0.36–0.70, P < 0.0001). However, subgroup analyses showed that in the primary prevention subgroup (OR 0.55, 95% CI 0.38–0.81, P = 0.002), atorvastatin reduced the risk of new-onset AF in patients after coronary surgery (OR 0.44, 95% CI 0.29–0.68, P = 0.0002), but had no beneficial effect in patients without coronary surgery (OR 0.97, 95% CI 0.59–1.58, P = 0.89); in the secondary prevention subgroup, atorvastatin had no beneficial effect on AF recurrence in patients with electrical cardioversion (EC) (OR 0.57, 95% CI 0.25–1.32, P = 0.19) or without EC (OR 0.38, 95% CI 0.14–1.06, P = 0.06).

Conclusions

This meta-analysis suggests that atorvastatin has an overall protective effect against AF. However, this preventive effect was not seen in all types of AF. Atorvastatin was significantly associated with a decreased risk of new-onset AF in patients after coronary surgery. Moreover, atorvastatin did not prove to exert a significant protective effect against the AF recurrences in both patients who had experienced sinus rhythm restoration by means of EC and those who had obtained cardioversion by means of drug therapy. Thus, further prospective studies are 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.

Statins and long-term survival after isolated valve surgery: the importance of valve type, position and procedure

OBJECTIVES

To investigate whether valve position, type and procedure are important factors in determining the beneficial effects of statin therapy with regard to long-term survival in patients undergoing isolated single valve surgery.

METHODS

A prospective single-institution cardiac surgery database was analysed. Univariate, multivariate stepwise linear, logistic and Cox regression analysis and propensity matching were performed to identify if statins were associated with increased survival post-valve surgery.

RESULTS

Overall mortality was 3.4% (n = 172) for all cases, n = 5013. The median follow-up was 5.8 years. Kaplan-Meier survival analysis indicated that statin therapy was beneficial for all patients undergoing isolated valve surgery, n = 5013, P = 0.03 and isolated aortic valve surgery, n = 3220, P = 0.03, but not isolated mitral valve surgery n = 1793, P = 0.4. Cox regression analysis of the study cohort revealed that statin therapy was a significant factors determining long-term survival in the study cohort, postisolated aortic valve replacement and postisolated biological aortic valve replacement. Statins therapy was not associated with an increased long-term survival post-mitral valve replacement or repair. Propensity matching resulted in 1555 patients receiving statins being matched 1:1 with those not receiving statins. The results after propensity matching concurred with that of the Cox regression analyses, demonstrating that statin therapy was significantly associated with reduced in-hospital mortality, hospital length of stay and postoperative creatinine kinase, muscle-brain isoenzyme release.

CONCLUSIONS

Previous publications have not distinguished valve type, position and repair as possible factors influencing statin-therapy outcomes. Statin therapy is associated with increased long-term survival postaortic valve replacement with a biological valve only. Statin therapy had no survival benefit in patients undergoing mitral valve repair or a mechanical valve replacement. A randomized trial is necessary to confirm or refute our findings.

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).

Statin therapy for the prevention of atrial fibrillation: a meta-analysis of randomized controlled trials

STUDY OBJECTIVES

To assess the efficacy of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) for primary and secondary prevention of atrial fibrillation, and to evaluate the efficacy of individual statins and their dosages.

DESIGN

Meta-analysis of 20 randomized controlled trials.

PATIENTS

A total of 32,311 patients who received either a statin (16,203 patients) or a placebo or active control regimen (16,108 patients) for either primary or secondary prevention of atrial fibrillation as part of a research study.

MEASUREMENTS AND MAIN RESULTS

A systemic literature search of MEDLINE, EMBASE, and the Cochrane Controlled Trials Register was performed to identify randomized controlled trials involving the prevention of atrial fibrillation with statin therapy. Effect size was expressed as odds ratio (OR) with 95% confidence interval (CI). Subgroup analysis was performed to explore the reasons for heterogeneity. Of the 20 trials, atorvastatin was studied in 11, pravastatin in five, rosuvastatin in three, and simvastatin in one. Overall, among the 32,311 patients in these trials, the risk of atrial fibrillation was significantly reduced by statins (OR 0.59, 95% CI 0.45-0.76), and the drugs were effective for both primary prevention (OR 0.67, 95% CI 0.51-0.88) and secondary prevention (OR 0.40, 95% CI 0.20-0.83). Secondary prevention was not superior to primary prevention, however. A significant benefit was observed in the atorvastatin-treated subgroup (OR 0.43, 95% CI 0.27-0.66), especially in the dose range of 10-40 mg/day (OR 0.29, 95% CI 0.19-0.45). No protective effect was observed in the pravastatin subgroup (OR 1.03, 95% CI 0.77-1.37).

CONCLUSION

This meta-analysis suggests that statin therapy is useful for the prevention of atrial fibrillation. The benefit of statins in secondary prevention was significant but not superior to primary prevention. Atorvastatin was more effective than pravastatin, and its effects were dose related, with lower doses being more effective. The number of trials focusing on individual drugs is still insufficient, and more randomized controlled trials are necessary to further support these conclusions.

Lipid-lowering therapy and coronary artery bypass graft surgery: what are the benefits?

PURPOSE OF REVIEW

Despite their apparent benefits, statins remain underutilized after coronary artery bypass graft (CABG) surgery. To summarize the literature regarding statin therapy and CABG, we performed a systematic review of the Medline database from 1987-2011 to assess the benefits of statins in CABG patients, including the role of high-dose therapy, and highlight areas for future study.

RECENT FINDINGS

When administered prior to CABG, statins reduce the risk of perioperative mortality, stroke, and atrial fibrillation. After CABG, statins limit the progression of atherosclerosis in native coronary arteries, inhibit the process of saphenous vein graft disease, and improve vein graft patency. Furthermore, postoperative statins reduce the recurrence of cardiovascular events and improve all-cause mortality. High-intensity statin therapy early after surgery may benefit CABG patients, but this is yet to be evaluated prospectively.

SUMMARY

Statins clearly improve the outcomes of CABG patients. In the absence of contraindications, all patients undergoing CABG are candidates for life-long statin therapy, with initiation recommended as soon as coronary disease is documented. Statins should be restarted early after surgery. However, the optimal postoperative lipid-lowering regimen remains unknown and should be the subject of upcoming trials. Strategies directed toward improving statin prescription rates and patient adherence should also be priorities for future research.

Upstream therapies for management of atrial fibrillation: review of clinical evidence and implications for European Society of Cardiology guidelines. Part II: secondary prevention

Fundamental research into molecular mechanisms of atrial fibrillation (AF) and improved understanding of processes involved in the initiation and maintenance of AF have transformed the traditional approach to its management by targeting only the electrical aspects, usually with antiarrhythmic drugs and, recently, by ablation. The antiarrhythmic potential of upstream therapies, such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers (ARBs), statins, and n-3 (ω-3) polyunsaturated fatty acids, extends beyond the benefit of treating underlying heart disease to modifying the atrial substrate and intervening in specific mechanisms of AF. The key target is structural remodelling of the atria, particularly inflammation and fibrosis, although there is evidence to suggest the direct involvement at the ion channel level. Positive clinical reports supported by robust experimental data have suggested that upstream therapies can be valuable strategies for primary prevention of AF in selected patients and have resulted in several class IIA recommendations in the new European guidelines on AF. However, these results have not been consistently replicated in the secondary prevention setting, and several recent randomized controlled studies failed to demonstrate any effect of upstream therapies on AF burden or on major cardiovascular outcomes. Part II of the review summarizes the evidence base for the use of upstream therapies for secondary prevention of AF.

Upstream therapies for management of atrial fibrillation: review of clinical evidence and implications for European Society of Cardiology guidelines. Part I: primary prevention

Atrial fibrillation (AF) is associated with significant morbidity and mortality. It is also a progressive disease secondary to continuous structural remodelling of the atria due to AF itself, to changes associated with ageing, and to deterioration of underlying heart disease. Current management aims at preventing the recurrence of AF and its consequences (secondary prevention) and includes risk assessment and prevention of stroke, ventricular rate control, and rhythm control therapies including antiarrhythmic drugs and catheter or surgical ablation. The concept of primary prevention of AF with interventions targeting the development of substrate and modifying risk factors for AF has emerged as a result of recent experiments that suggested novel targets for mechanism-based therapies. Upstream therapy refers to the use of non-antiarrhythmic drugs that modify the atrial substrate- or target-specific mechanisms of AF to prevent the occurrence or recurrence of the arrhythmia. Such agents include angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), statins, n-3 (ω-3) polyunsaturated fatty acids, and possibly corticosteroids. Animal experiments have compellingly demonstrated the protective effect of these agents against electrical and structural atrial remodelling in association with AF. The key targets of upstream therapy are structural changes in the atria, such as fibrosis, hypertrophy, inflammation, and oxidative stress, but direct and indirect effects on atrial ion channels, gap junctions, and calcium handling are also applied. Although there have been no formal randomized controlled studies (RCTs) in the primary prevention setting, retrospective analyses and reports from the studies in which AF was a pre-specified secondary endpoint have shown a sustained reduction in new-onset AF with ACEIs and ARBs in patients with significant underlying heart disease (e.g. left ventricular dysfunction and hypertrophy), and in the incidence of AF after cardiac surgery in patients treated with statins. In the secondary prevention setting, the results with upstream therapies are significantly less encouraging. Although the results of hypothesis-generating small clinical studies or retrospective analyses in selected patient categories have been positive, larger prospective RCTs have yielded controversial, mostly negative, results. Notably, the controversy exists on whether upstream therapy may impact mortality and major non-fatal cardiovascular events in patients with AF. This has been addressed in retrospective analyses and large prospective RCTs, but the results remain inconclusive pending further reports. This review provides a contemporary evidence-based insight into the role of upstream therapies in primary (Part I) and secondary (Part II) prevention of AF.