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 post-operative major adverse events despite significant advances in surgical techniques and perioperative care. Statins (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.

OBJECTIVES

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

SEARCH METHODS

We searched CENTRAL (Issue 2 of 4, 2010 on The Cochrane Library), MEDLINE (1950 to May, Week 1 2010), EMBASE (1980 to 2010 Week 19), and the metaRegister of Controlled Trials. Additionally, ongoing trials were searched through the National Research Register, the ClinicalTrials.gov registry and grey literature. Conference indices from relevant scientific meetings (2006-2009) were screened online for eligible trials. No language restrictions were applied.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

Two authors evaluated trial quality and extracted data from titles and abstracts identified from the electronic database searches according to pre-defined criteria. Accordingly, full text articles of potentially relevant studies that met the inclusion criteria were retrieved to assess definite eligibility for inclusion. Effect measures are reported as odds ratios (OR) or weighted mean difference (WMD) with 95% confidence intervals (95%-CI).

MAIN RESULTS

Eleven randomized controlled studies including a total of 984 participants undergoing on- or off-pump cardiac surgical procedures were identified. Pooled analysis showed that statin pre-treatment before surgery reduced the incidence of post-operative atrial fibrillation (AF) (OR 0.40; 95%-CI: 0.29 to 0.55; p<0.01), but failed to influence short-term mortality (OR 0.98, 95%-CI: 0.14 to 7.10; p=0.98) or post-operative stroke (OR 0.70, 95%-CI: 0.14 to 3.63; p=0.67). In addition, statin therapy was associated with a shorter length of stay of patients on the intensive care unit (ICU) (WMD: -3.39 hours; 95%-CI: -5.77 to -1.01) and in-hospital (WMD: -0.48 days; 95%-CI: -0.85 to -0.11) where significant heterogeneity was observed. There was no reduction in myocardial infarction (OR 0.52; 95%-CI: 0.2. to 1.30) or renal failure (OR 0.41; 95%-CI: 0.15 to 1.12). These results were unaffected after subgroup analysis. No major or minor perioperative statin side-effects were reported from trials investigating this safety endpoint.

AUTHORS' CONCLUSIONS

Preoperative statin therapy reduces the odds of post-operative AF and shortens the stay on the ICU and in the hospital. Statin pretreatment had no influence on perioperative mortality, stroke, myocardial infarction or renal failure. Since analysed studies included mainly patients undergoing myocardial revascularizations the results cannot be extrapolated to patients undergoing other cardiac procedures such as heart valve or aortic 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.

The effects of statin on atrial fibrillation: a meta-analysis of published data from randomized controlled trials

BACKGROUND

Some clinical and experimental studies have shown the use of statins could protect against AF, but there are not adequate data at present.

OBJECTIVES

We performed a meta-analysis of randomized trials with statins on the endpoint of incidence of AF to estimate the impact of statin use on AF development.

METHODS

We searched PUBMED, EMBASE and the Cochrane controlled Trials Register (Cochrane Library Issue 4, 2010) up to November 2010 to identify studies covering the use of statins on atrial fibrillation.

RESULTS

In published data from nine short term trials (1044 patients, 421 AF), the effect of statins was significantly associated with a decreased risk of recurrence of AF (OR 0.43, 95% CI 0.25 to 0.73, P = 0.002). The result of OR was higher when studies with Jadad score ≤3 were excluded (OR 0.32, 95% CI 0.18 to 0.54, P ≤ 0.0001). Among four long term trials (12,442 patients, 618 AF), the effect of statins was associated with a decreased risk of recurrence of AF (OR 0.81, 95% CI 0.68 to 0.97, P = 0.02). In three long term trials of more intensive versus standard statin (9130 patients, 188 AF), there was no evidence of a reduction in the risk of AF (OR 1.05, 95% CI 0.79 to 1.40, P= 0.74).

CONCLUSION

Our meta-analysis suggests that the use of statins may be associated with preventing AF in short term trials and long term trials, but in the long term trials of more intensive versus standard statin, there was no evidence of a reduction in the risk of AF. However, we still need large-scale randomized double blind statin trials with AF occurrence as the main endpoint in order to finally confirm the benefits of statin in AF patients.

Do Statins Reduce Atrial Fibrillation After Coronary Artery Bypass Grafting?

Background: Atrial Fibrillation (AF) is a common postoperative complication after coronary artery bypass grafting. There is contradictory evidence as to whether pre-operative statin use lowers the incidence of postoperative AF. This study aimed to assess whether pre operative statin therapy prevents the post-operative AF. Methods: In this retrospective cohort study we used a propensity score-matching analysis to evaluate the effect of preoperative treatment with statins on postoperative atrial fibrillation. There were 427 matched pairs of patients. Primary outcome was the incidence of postoperative AF. Secondary outcomes were 30 day mortality, stroke, myocardial infarction and length of hospital stay. Results: The incidence of postoperative AF was not different in the statin users compared with the nonusers (123, 28.1%, versus 127, 29.7%, respectively; p = 0.764). The 30 day mortality (6, 1.4%, versus 8, 1.9%; p = 0.590), stroke (10, 2.3%, versus 8, 1.9%; p = 0.634), myocardial infarction (2, 0.5%, versus 0, 0.0%; p = 0.499) and length of hospital stay in days (11.8 ± 9.0, versus 11.9 ± 9.3; p = 0.544) did not differ significantly between the two groups. Conclusions: In a propensity-matched cohort of patients undergoing coronary bypass surgery, we could not demonstrate that preoperative statins were protective for the development of post operative atrial fibrillation.

Effect of early statin therapy on risk of atrial fibrillation after coronary artery bypass grafting with or without concomitant valve surgery

Statins decrease postoperative atrial fibrillation (AF) if given before cardiac surgery. However, whether early administration of statins after surgery decreases the risk of postoperative AF is unknown. The association of early reinstitution of postoperative statin therapy within 48 hours to the occurrence of postoperative AF was studied in propensity-adjusted analyses of 200 consecutive patients in sinus rhythm who had undergone coronary artery bypass grafting with or without valve surgery. Postoperative AF occurred in 36 patients (18%). Of 52 patients who received a statin early after surgery, 4 (7.7%) developed AF compared to 32 (28%) of 148 patients who did not (p = 0.043). In the propensity-adjusted analyses, early postoperative statin treatment was associated with a significantly lower occurrence of AF (odds ratio 0.39, 95% confidence interval 0.15 to 0.99), irrespective of concomitant β-blocker therapy. The length of stay was shorter for the patients who received early postoperative statins (median 6.1 days, interquartile range 4 to 7, vs 7.8 days, interquartile range 5 to 8; p = 0.0031). In conclusion, of preoperative statin users undergoing coronary artery bypass grafting with or without valve surgery, early postoperative reinstitution of statins was associated with a lower occurrence of postoperative AF and a shorter length of stay. Early postoperative statin therapy might be a feasible and safe method of reducing postoperative AF.

High-dose atorvastatin and risk of atrial fibrillation in patients with prior stroke or transient ischemic attack: analysis of the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial

BACKGROUND

Observational analyses and short-term randomized trials have suggested that statins reduce occurrence or recurrence of atrial fibrillation (AF). We tested the hypothesis that long-term treatment with high-dose atorvastatin reduces occurrence of AF in patients with prior stroke or transient ischemic attack.

METHODS

We examined development of new AF in the SPARCL trial that compared atorvastatin 80 mg daily with placebo in 4,731 patients with prior stroke or transient ischemic attack. Patients who had chronic or paroxysmal AF or were taking medications for treatment or prophylaxis of AF at the time of enrollment were excluded. Atrial fibrillation was identified from electrocardiograms submitted to a blinded central electrocardiographic laboratory and from investigators' adverse event reports.

RESULTS

Patients were followed up for a median of 4.8 years, corresponding to >20,000 patient-years of observation with a median of 5 electrocardiograms per patient. The primary efficacy measure, the time from randomization to first occurrence of new AF, did not differ between treatment groups. By intention to treat, there were 139 cases of new AF in the atorvastatin group and 122 cases in the placebo group, corresponding to incidence rates of 1.32 and 1.14 cases per 100 patient-years observation (hazard ratio 1.15, 95% CI 0.90-1.46, P = .26). On-treatment analysis yielded similar findings, with incidence rates of 1.26 and 1.01 cases per 100 patient-years observation in the atorvastatin and placebo groups, respectively (hazard ratio 1.25, 95% CI 0.94-1.67, P = .12).

CONCLUSION

High-dose atorvastatin does not prevent development of AF in patients with prior stroke or transient ischemic attack.

Usefulness of statins pretreatment for the prevention of postoperative atrial fibrillation in patients undergoing cardiac surgery

BACKGROUND

postoperative atrial fibrillation (AF) remains the most common arrhythmic complication following cardiac surgery. We performed a meta-analysis based on all currently available randomized controlled trials (RCTs) to confirm the hypothesis that statins pretreatment may lower the risk of postoperative AF in patients undergoing cardiac surgery.

METHODS AND RESULTS

the published literature was scanned by formal searches of electronic databases up through August 2010. RCTs were eligible for inclusion if they compared preoperative statins treatment versus control in patients scheduled for cardiac surgery and had the data of postoperative AF reported. Prespecified criteria were met by eight RCTs involving 841 patients. During the follow-up period, 80 of 422 patients (19.0%) in the statins pretreatment group developed postoperative AF, significantly less than 149 of 419 (35.6%) patients assigned to the control group ( P < 0.001). Postoperative hospital stay was significantly shortened in patients pretreated with statins compared with the control ( P < 0.01).

CONCLUSIONS

this meta-analysis supports the effectiveness of statins pretreatment on reducing the incidence of postoperative AF in patients undergoing cardiac surgery.

Upstream effect for atrial fibrillation: still a dilemma?

Atrial fibrillation is the most common arrhythmia in clinical practice. Ion channel blocking agents are often characterized by limited long-term efficacy and several side effects. In addition, ablative invasive procedures are neither easily accessible nor always efficacious. The "upstream therapy," which includes angiotensin-converting enzyme inhibitors, aldosterone receptor antagonists, statins, glucocorticoids, and ω-3 poly-unsaturated fatty acids, targets arrhythmia substrate, influencing atrial structural and electrical remodeling that play an essential role in atrial fibrillation induction and maintenance. The mechanisms involved and the most important clinical evidence regarding the upstream therapy influence on atrial fibrillation are presented in this review. Some open questions are also proposed.

Evidence of pre-procedural statin therapy a meta-analysis of randomized trials

OBJECTIVES

The purpose of this study was to summarize the evidence of pre-procedural statin therapy to reduce periprocedure cardiovascular events.

BACKGROUND

Invasive procedures can result in adverse cardiovascular events, such as myocardial infarction (MI) and death. We hypothesized that statins might improve clinical outcomes when used before invasive procedures.

METHODS

We searched the MEDLINE, Cochrane, and clinicaltrials.gov databases from inception to February 2010 for randomized, controlled trials that examined statin therapy before invasive procedures. Invasive procedures were defined as percutaneous coronary intervention, coronary artery bypass grafting (CABG), and noncardiac surgery. We required that studies initiated statins before the procedure and reported clinical outcomes. A DerSimonian-Laird model was used to construct random-effects summary risk ratios.

RESULTS

Eight percent of the screened trials (21 of 270) met our selection criteria, which included 4,805 patients. The use of pre-procedural statins significantly reduced post-procedural MI (risk ratio [RR]: 0.57, 95% confidence interval [CI]: 0.46 to 0.70, p < 0.0001). This benefit was seen after both percutaneous coronary intervention (p < 0.0001) and noncardiac surgical procedures (p = 0.004), but not CABG (p = 0.40). All-cause mortality was nonsignificantly reduced by statin therapy (RR: 0.66, 95% CI: 0.37 to 1.17, p = 0.15). Pre-procedural statins also reduced post-CABG atrial fibrillation (RR: 0.54, 95% CI: 0.43 to 0.68, p < 0.0001).

CONCLUSIONS

Statins administered before invasive procedures significantly reduce the hazard of post-procedural MI. Additionally, statins reduce the risk of atrial fibrillation after CABG. The routine use of statins before invasive procedures should be considered.