Statin therapy improves outcomes after valvular heart surgery

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.

Risk score for arch reconstruction under circulatory arrest with hypothermia: The ARCH score

OBJECTIVE

Currently, there is no risk scores built to predict risk in thoracic aortic surgery. This study aims to develop and internally validate a risk prediction score for patients who require arch reconstruction with hypothermic circulatory arrest.

METHODS

From 2002 to 2018, data for 2270 patients who underwent aortic arch surgery in 12 institutions in Canada were retrospectively collected. The outcomes modeled included in-hospital mortality and a modified Society of Thoracic Surgeons-defined composite for mortality or major morbidity. Multivariable logistic regression using least absolute shrinkage and selection operator selection method and mixed-effect regression model was used to select the predictors. Internal calibration of the final models is presented with an observed-versus-predicted plot.

RESULTS

There were 182 in-hospital deaths (8.0%), and the incidence of Society of Thoracic Surgeons-defined composite for mortality or major morbidity was 27.9%. Variables that increased risk of mortality are age, chronic obstructive pulmonary disease, atrial fibrillation, peripheral vascular disease, New York Heart Association class ≥III symptoms, acute aortic dissection or rupture, use of elephant trunk, concomitant surgery, and increased cardiopulmonary bypass time, with median c-statistics of 0.85 on internal validation. The c-statistics was 0.77 for the model predicting Society of Thoracic Surgeons-defined composite. Internal assessment shows good overall calibration for both models.

CONCLUSIONS

We developed and internally validated a risk score for patients undergoing arch surgery requiring hypothermic circulatory arrest using a multicenter database. Once externally validated, the ARCH (Arch Reconstruction under Circulatory arrest with Hypothermia) score would allow for better patient risk-stratification and aid in the decision-making process for surgeons and patient prior to surgery.

Effect of statin on perioperative myocardial injury in isolated valve surgery

BACKGROUND

Statins have known pleiotropic effects that confer protection from ischemia-reperfusion injury. Because cardiopulmonary bypass is a potentially reversible ischemia-reperfusion sequence, we aimed to assess whether statin loading could help to limit myocardial injury in patients undergoing isolated heart valve replacement under cardiopulmonary bypass.

METHODS

One hundred patients with rheumatic valvular heart disease undergoing valve replacement received either a loading dose of rosuvastatin (40 mg initiated 7 days before surgery; loaded group) or no statins (non-loaded group). Cardiac troponin I, creatine kinase MB, and brain natriuretic peptide were measured at 8, 24, and 48 hours postoperatively. The primary endpoint was the extent of perioperative myocardial injury measured by the area under the curve for each biomarker.

RESULTS

Despite similar baseline levels, all biomarkers at 8, 24, and 48 h were significantly lower in the loaded group. The area under the curve of each biomarker was significantly lower in the loaded group than in the non-loaded group (troponin I: 31.43 vs. 77.21 ng·h·mL^-1, creatine kinase MB 309.31 vs. 429.12 ng·h·mL^-1, brain natriuretic peptide 5176.11 vs. 16119.31 pg·h·mL^-1, all p < 0.001). The mean changes from baseline to peak levels were also significantly lower in the loaded group. The loaded group had a shorter hospital stay but no significant difference was seen in ventilator time, inotrope time, aortic crossclamp time, cardiopulmonary bypass time, or intensive care unit stay.

CONCLUSION

In patients undergoing valve replacement, high-dose statin loading before surgery had a favorable impact on the release kinetics of various cardiac biomarkers.

Neuroprotection against stroke and encephalopathy after cardiac surgery

Cerebral ischemia in the perioperative period is a major risk factor for stroke, encephalopathy, and cognitive decline after cardiothoracic surgery. After coronary artery bypass grafting, both stroke and encephalopathy can result in poor patient outcomes and increased mortality. Neuroprotection aims to lessen the severity and occurrence of further injury mediated by stroke and encephalopathy and to aid the recovery of conditions already present. Several pharmacological and non-pharmacological methods of neuroprotection have been investigated in experimental studies and in animal models, and, although some have shown effectiveness in protection of the central nervous system, for most, clinical research is lacking or did not show the expected results. This review summarizes the value and need for neuroprotection in the context of cardiothoracic surgery and examines the use and effectiveness of several agents and methods with an emphasis on clinical trials and clinically relevant neuroprotectants.

Preoperative Statin Use Not Associated With Improved Outcomes After Ascending Aortic Repair

Statins have potent pleiotropic effects that have been correlated with improved perioperative cardiovascular surgery outcomes. We hypothesize that statins may improve morbidity and mortality after ascending aortic surgery. Within a statewide database consisting of 19 centers a total of 1804 patients had ascending aortic repair with or without aortic valve replacement (2004-2016). Patients were stratified by preoperative statin therapy for analysis. To account for baseline differences, patients were propensity matched in a 1:1 fashion by baseline characteristics. Patient characteristics and outcomes were analyzed by paired analysis. Of 1804 patients undergoing ascending aortic repair, 35% took statins preoperatively. After matching, 386 patients in each group were well matched with no statistically significant baseline or operative differences. There was no statistically significant difference in outcomes between patients taking statins preoperatively and those not taking statins, including operative mortality (3.6% vs 3.1%, P = 0.68) and major morbidity (18.4% vs 17.1%, P = 0.62). Postoperative atrial fibrillation (27.2% vs 28.5%, P = 0.71) and acute kidney injury (3.1% vs 4.2%, P = 0.41) also showed no statistically significant difference. Statins have no apparent clinical impact on perioperative outcomes after ascending aortic aneurysm repair. Considering recent evidence suggesting statins may increase perioperative risk of acute kidney injury, there is insufficient evidence to recommend starting preoperative statin before ascending aortic repair.

Postoperative Cardiac Surgery Outcomes in a Statin-Native Population

Background

Statin utilization had been associated with improved survival after cardiac surgery. We aim to study whether perioperative treatment with statin could be associated with increased postoperative complications.

Design

This was a retrospective, descriptive, single-center study.

Settings

We analyzed morbidity after cardiac surgery as well as the outcome related to statin therapy in a tertiary cardiac center.

Patients

A total of 202 consecutive patients were enrolled over 1 year after cardiac surgery.

Intervention

Patients were divided into two groups; Group I - statin users and Group II - nonusers.

Measurements

Measurements were baseline and follow-up laboratory markers for muscular injury including cardiac muscle and hepatic injuries and renal injuries.

Results

The incidence of rhabdomyolysis and elevation of liver enzymes did not differ between both groups. Postoperative atrial fibrillation was significantly lower in the statin group (P = 0.02). In addition, peak cardiac troponin and creatine kinase-MB did not differ significantly in the statin group. Statin-treated group had significant lower length of mechanical ventilation, and length of stay in the Intensive Care Unit and hospital (P = 0.036, 0.04, and 0.027, respectively).

Conclusions

Therapy with statin before cardiac surgeries was not associated with high incidence of adverse events.

Factors associated with postoperative atrial fibrillation and other adverse events after cardiac surgery

OBJECTIVE

The study objective was to evaluate the impact of various surgical characteristics and practices on the risk of postoperative atrial fibrillation and other adverse outcomes after cardiac surgery.

METHODS

By using the prospectively collected data of patients who underwent cardiac surgery in 28 centers across the United States, Italy, and Argentina, the details of surgery characteristics were collected for each patient and the outcomes, including postoperative atrial fibrillation, major adverse cardiovascular events, and mortality. These were evaluated via multivariable-adjusted models.

RESULTS

In 1462 patients, a total of 460 cases of postoperative atrial fibrillation, 33 major adverse cardiovascular events, 23 cases of 30-day mortality, and 46 cases of 1-year mortality occurred. We found that type of surgery and cardiopulmonary bypass use predicted the occurrence of postoperative atrial fibrillation. Compared with coronary artery bypass grafting alone, there was a higher risk of postoperative atrial fibrillation with valvular surgery alone (odds ratio, 1.4; 95% confidence interval, 1.1-1.9), and the risk was even higher with concomitant valvular and coronary artery bypass grafting surgery (odds ratio, 1.8; 95% confidence interval, 1.2-2.7). Compared with no bypass, use of cardiopulmonary bypass was associated with higher risk of postoperative atrial fibrillation (odds ratio, 2.4; 95% confidence interval, 1.7-3.5), but there were significant age and sex differences of the impact of bypass use among patients undergoing coronary artery bypass grafting (P for interaction = .04). In addition, compared with spontaneous return of rhythm, ventricular pacing was associated with a higher risk of major adverse cardiovascular events (odds ratio, 5.0; 95% confidence interval, 1.4-18), whereas concomitant coronary artery bypass grafting and valvular surgery was associated with a higher risk of 30-day mortality (hazard ratio, 4.3; 95% confidence interval, 1.2-14) compared with coronary artery bypass grafting alone. Occurrence of postoperative atrial fibrillation was associated with greater length of stay and 1-year mortality (hazard ratio, 2.2; 95% confidence interval, 1.2-3.9).

CONCLUSIONS

In this multicenter trial, we identified specific adverse outcomes that are associated with concomitant valvular and coronary artery bypass graft surgery, cardiopulmonary bypass, ventricular pacing, and occurrence of postoperative atrial fibrillation.

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.

High-Dose Perioperative Atorvastatin and Acute Kidney Injury Following Cardiac Surgery: A Randomized Clinical Trial

IMPORTANCE

Statins affect several mechanisms underlying acute kidney injury (AKI).

OBJECTIVE

To test the hypothesis that short-term high-dose perioperative atorvastatin would reduce AKI following cardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

Double-blinded, placebo-controlled, randomized clinical trial of adult cardiac surgery patients conducted from November 2009 to October 2014 at Vanderbilt University Medical Center.

INTERVENTIONS

Patients naive to statin treatment (n = 199) were randomly assigned 80 mg of atorvastatin the day before surgery, 40 mg of atorvastatin the morning of surgery, and 40 mg of atorvastatin daily following surgery (n = 102) or matching placebo (n = 97). Patients already taking a statin prior to study enrollment (n = 416) continued taking the preenrollment statin until the day of surgery, were randomly assigned 80 mg of atorvastatin the morning of surgery and 40 mg of atorvastatin the morning after (n = 206) or matching placebo (n = 210), and resumed taking the previously prescribed statin on postoperative day 2.

MAIN OUTCOMES AND MEASURES

Acute kidney injury defined as an increase of 0.3 mg/dL in serum creatinine concentration within 48 hours of surgery (Acute Kidney Injury Network criteria).

RESULTS

The data and safety monitoring board recommended stopping the group naive to statin treatment due to increased AKI among these participants with chronic kidney disease (estimated glomerular filtration rate <60 mL/min/1.73 m2) receiving atorvastatin. The board later recommended stopping for futility after 615 participants (median age, 67 years; 188 [30.6%] were women; 202 [32.8%] had diabetes) completed the study. Among all participants (n = 615), AKI occurred in 64 of 308 (20.8%) in the atorvastatin group vs 60 of 307 (19.5%) in the placebo group (relative risk [RR], 1.06 [95% CI, 0.78 to 1.46]; P = .75). Among patients naive to statin treatment (n = 199), AKI occurred in 22 of 102 (21.6%) in the atorvastatin group vs 13 of 97 (13.4%) in the placebo group (RR, 1.61 [0.86 to 3.01]; P = .15) and serum creatinine concentration increased by a median of 0.11 mg/dL (10th-90th percentile, -0.11 to 0.56 mg/dL) in the atorvastatin group vs by a median of 0.05 mg/dL (10th-90th percentile, -0.12 to 0.33 mg/dL) in the placebo group (mean difference, 0.08 mg/dL [95% CI, 0.01 to 0.15 mg/dL]; P = .007). Among patients already taking a statin (n = 416), AKI occurred in 42 of 206 (20.4%) in the atorvastatin group vs 47 of 210 (22.4%) in the placebo group (RR, 0.91 [0.63 to 1.32]; P = .63).

CONCLUSIONS AND RELEVANCE

Among patients undergoing cardiac surgery, high-dose perioperative atorvastatin treatment compared with placebo did not reduce the risk of AKI overall, among patients naive to treatment with statins, or in patients already taking a statin. These results do not support the initiation of statin therapy to prevent AKI following cardiac surgery.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00791648.

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.

Effect of preoperative statin therapy on postoperative acute kidney injury in patients undergoing major surgery: systemic review and meta-analysis

We aimed to examine the association between preoperative use of statins and postoperative acute kidney injury (AKI) in patients undergoing major surgery by performing a systemic review and meta-analysis. MEDLINE and EMBASE, from inception to April 2013, and the reference lists of related articles were searched for relevant studies. Trials comparing preoperative statin therapy with no preoperative statin in patients undergoing major surgery were included. Outcome measures of interest were the risk of cumulative postoperative AKI and postoperative AKI requiring renal replacement therapy (RRT). Fixed or random effect meta-analysis was performed to derive summary effect estimates. In five randomized controlled trials (RCTs) and 19 observational studies, comprising a total of 989 173 patients undergoing major surgery, 112 840 patients (11.41%) received preoperative statin therapy. The specific type, dosage, and duration of statin therapy were not available in most studies. Preoperative statin therapy was associated with a significant risk reduction for cumulative postoperative AKI (weighted summary odds ratio (OR) 0.87, 95% CI 0.79 to 0.95). The effect of risk reduction was also significant when considering postoperative AKI requiring RRT (OR 0.80, 95% CI 0.72 to 0.90). When restricting the analysis to the five RCTs, preoperative statin therapy did not show significant protective effect on postoperative AKI (OR 0.49, 95% CI 0.22 to 1.09). In patients undergoing major surgery, preoperative statin therapy could associate with a reduced risk for postoperative AKI. However, considerable heterogeneity existed among included studies. Future randomized trials were warranted for this critical clinical question.

Pleiotropic vascular protective effects of statins in perioperative medicine

3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor (statins) is one of the most commonly prescribed agents for controlling hyperlipidemia. Apart from their lipid-lowering property, statins are well known for their pleiotropic effects, such as improvement of vascular endothelial dysfunction, attenuation of inflammatory responses, stabilization of atherosclerotic plaques, inhibition of vascular smooth muscle proliferation, and modulation of procoagulant activity and platelet function. The vasculo-protective effect of statins is mainly mediated by inhibition of the mevalonate pathway and oxidized low-density lipoprotein generation, thereby enhancing the biosynthesis of endothelium-derived nitric oxide. Accumulating clinical evidence strongly suggests that administration of statins reduces overall mortality, the development myocardial infarction and atrial fibrillation, and length of hospital stay after a major cardiac/noncardiac surgery. This review updates the clinical pharmacology and therapeutic applications of statins during major operations, and highlights the anesthesia considerations for perioperative statin therapy.

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.

Can statins improve outcomes after isolated cardiac valve surgery? A systematic literature review

BACKGROUND

HMG CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors, or statins, have been associated with an improvement in outcomes after coronary artery surgery for some time; however, their role in isolated valve surgery (IVS) remains undetermined.

HYPOTHESIS

The pleiotropic effects of statins may produce similar beneficial effects on outcomes after IVS.

METHODS

A systematic review of the literature was performed investigating the role of statins in bioprosthetic valve replacement.

RESULTS

Nine observational studies (7 retrospective, 2 prospective) incorporating a total of 18 154 patients were found investigating the role of statin therapy in bioprosthetic valve replacement.

CONCLUSIONS

There is presently insufficient evidence to recommend routine statin therapy in IVS, unless concomitant hypercholesterolemia or coronary artery disease is present. A prospective study clearly defining the dose, type, and duration of therapy is now required to finally clarify whether statins alone confer a postoperative benefit in these patients.

Preoperative statin therapy is associated with lower requirement of renal replacement therapy in patients undergoing cardiac surgery: a meta-analysis of observational studies

OBJECTIVES

Acute kidney injury (AKI) following cardiac surgery is a common complication associated with serious morbidity and mortality. Activation of inflammatory cascade and vascular endothelial dysfunction plays a vital role during the perioperative period leading to AKI. Statins are known to suppress inflammation and improve endothelial dysfunction over and above the cholesterol lowering efficacy.

METHODS

Observational studies with a defined population in terms of preoperative statin therapy and no preoperative statin therapy undergoing cardiac surgery (CABG, isolated valve surgery or both) and with reported data on the incidence of acute renal failure/injury and/or mortality were identified and analysed for inclusion in the analysis. Outcomes evaluated were occurrence of postoperative acute kidney injury/failure, requirement of any postoperative renal replacement therapy and short-term all-cause mortality rate. A meta-analysis was conducted and a pooled estimate of odds ratio (OR) was calculated using the inverse variance method.

RESULTS

A total of 17 studies with a total population of 24 998 statin users and 22 082 non-statin users were included in the final analysis. PST resulted in a significantly lower incidence of renal replacement therapy in patients undergoing CABG (OR: 0.56 [0.41-0.76]) but not in isolated valve surgery (OR: 1.80 [0.73-4.44]). Also preoperative statin therapy resulted in a significantly lower postoperative mortality (0.72 [0.61-0.84]) irrespective of the type of surgery. There was no effect of preoperative statin therapy on the incidence of AKI in any of the sub-group of the patients.

CONCLUSIONS

Patients undergoing CABG might derive benefit from preoperative statin therapy in terms of reducing the need for postoperative renal replacement therapy and mortality. However, the uncertainty concerning the reno-protective efficacy of preoperative statin therapy in patients undergoing isolated valve surgery needs further investigation.

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.

Preoperative statin therapy in cardiac surgery is more effective in patients who display preoperative activation of the inflammatory system

We sought to determine whether preoperative statin treatment is more effective in reducing, after cardiac surgery with cardiopulmonary bypass, systemic inflammatory response and myocardial damage markers in patients who have elevated preoperative interleukin-6 levels than in patients who have normal preoperative interleukin-6 levels. The study involved a prospective cohort of 164 patients who underwent coronary and valvular surgery with cardiopulmonary bypass. There were 2 study groups: group A (n = 60), patients with elevated preoperative interleukin-6 levels; and group B (n = 104), patients with normal preoperative interleukin-6 levels. Each group was subdivided according to whether patients were (group 1) or were not (group 2) treated preoperatively with statins. Accordingly, the subdivided study groups were A1 (n = 40), A2 (n = 20), B1 (n = 56), and B2 (n = 48). The plasma levels of proinflammatory interleukin-6 were measured 1, 6, 24, and >72 hours after surgery. The baseline, operative, and postoperative morbidity and mortality characteristics were similar in all groups. Group A1 had significantly lower levels of interleukin-6 and troponin I than did group A2 at all postoperative time points. Group B1 had significantly lower levels of interleukin-6 than did group B2 postoperatively. There were no significant differences in troponin I levels between groups B1 and B2. We conclude that, in patients with preoperative activation of the inflammatory system, preoperative treatment with statins is associated with lower postoperative interleukin-6 and troponin I levels after cardiac surgery with cardiopulmonary bypass.

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.

Current evidence for perioperative statins in cardiac surgery

Cardiac surgery improves life expectancy and quality of life for the constantly ageing population in developed countries. Mediated by their lipid-dependent and lipid-independent mechanisms, statins are sought to provide benefit with regard to better outcomes after cardiac surgery. Current guidelines recommend statin use in patients undergoing coronary artery bypass grafting, while less evidence is available for patients referred to heart valve surgery. Optimal selection of statin drug and dosage including perioperative timing of statin therapy remains largely unknown, but results of ongoing meta-analyses and future randomized trials will add important evidence to guide perioperative statin treatment of cardiac surgery patients.

ESC Working Group on Valvular Heart Disease Position Paper: assessing the risk of interventions in patients with valvular heart disease

AIMS

Risk scores provide an important contribution to clinical decision-making, but their validity has been questioned in patients with valvular heart disease (VHD), since current scores have been mainly derived and validated in adults undergoing coronary bypass surgery. The Working Group on Valvular Heart Disease of the European Society of Cardiology reviewed the performance of currently available scores when applied to VHD, in order to guide clinical practice and future development of new scores.

METHODS AND RESULTS

The most widely used risk scores (EuroSCORE, STS, and Ambler score) were reviewed, analysing variables included and their predictive ability when applied to patients with VHD. These scores provide relatively good discrimination, i.e. a gross estimation of risk category, but cannot be used to estimate the exact operative mortality in an individual patient because of unsatisfactory calibration.

CONCLUSION

Current risk scores do not provide a reliable estimate of exact operative mortality in an individual patient with VHD. They should therefore be interpreted with caution and only used as part of an integrated approach, which incorporates other patient characteristics, the clinical context, and local outcome data. Future risk scores should include additional variables, such as cognitive and functional capacity and be prospectively validated in high-risk patients. Specific risk models should also be developed for newer interventions, such as transcatheter aortic valve implantation.

Preoperative Statins and Acute Kidney Injury After Cardiac Surgery: Utilization of a Consensus Definition of Acute Kidney Injury

Background

Previous trials investigating preoperative statin use for prevention of acute kidney injury following cardiovascular surgery were limited to patients undergoing a specific procedure and many used nonconsensus definitions of acute kidney injury.

Objective

To use a consensus definition of acute kidney injury for evaluating the association of preoperative statin use with the development of acute kidney injury following cardiac surgery utilizing cardiopulmonary bypass.

Methods

We retrospectively evaluated a cohort of 667 patients ≥18 years who underwent any cardiac surgery on cardiopulmonary bypass between April 2007 and May 2009 at Mercy Hospital in Scranton, PA. Patients were excluded if they were receiving preoperative renal replacement therapy, had stage 5 chronic kidney disease, or did not have a postoperative serum creatinine level assessed. The primary outcome was the odds of developing acute kidney injury given the use of preoperative statins. Acute kidney injury was defined based on the Acute Kidney Injury Network criteria as either an absolute increase in serum creatinine of ≥0.3 mg/dL or 1.5 times baseline, or the need for postoperative renal replacement therapy.

Results:

The final analysis included 563 patients; 356 were receiving preoperative statins. The incidence of acute kidney injury was 35.1% in the statin group and 26.1% in the non-statin group. On univariate analysis statins were associated with an increase in the odds of acute kidney injury (OR 1.53; 95% CI 1.05 to 2.24). Multivariate logistic regression did not demonstrate an association of statins with acute kidney injury (OR 1.36; 95% CI 0.904 to 2.05). Repeating the analysis using 312 propensity score–matched patients also showed no association of statins with acute kidney injury (OR 1.17; 95% CI 0.715 to 1.93).

Conclusions:

Our findings do not support the hypothesis that preoperative statin use is associated with a decrease in the incidence of acute kidney injury following cardiac surgery utilizing cardiopulmonary bypass.

Progress in perioperative medicine: focus on statins

Beyond cholesterol reduction, statins have multiple beneficial influences on vascular endothelial function, atherosclerotic plaque stability, inflammation, and thrombosis. These favorable pleiotropic effects may be the basis for their perioperative risk reduction in cardiothoracic and vascular procedures. The published evidence suggests that statins offer significant outcome benefits throughout perioperative practice. Because statin therapy significantly reduces the perioperative risk for patients undergoing cardiovascular procedures, they already are recommended in published guidelines. Beyond cardiac risk reduction, statin therapy also may protect the brain and the kidney in the perioperative setting, both in cardiac and vascular surgery. The pleiotropic effects of statins also appear to have therapeutic roles in the progression of valve disease, sepsis, and venous thrombosis. Further trials are required to provide data to drive their safe and comprehensive perioperative application for optimal patient outcome both in the short term and the long term. Because there are multiple randomized trials currently in progress throughout perioperative medicine, it is very likely that the indications for statins will be expanded significantly.

The case for developing publicly-accessible datasets for health services research in the Middle East and North Africa (MENA) region

BACKGROUND

The existence of publicly-accessible datasets comprised a significant opportunity for health services research to evolve into a science that supports health policy making and evaluation, proper inter- and intra-organizational decisions and optimal clinical interventions. This paper investigated the role of publicly-accessible datasets in the enhancement of health care systems in the developed world and highlighted the importance of their wide existence and use in the Middle East and North Africa (MENA) region.

DISCUSSION

A search was conducted to explore the availability of publicly-accessible datasets in the MENA region. Although datasets were found in most countries in the region, those were limited in terms of their relevance, quality and public-accessibility. With rare exceptions, publicly-accessible datasets - as present in the developed world - were absent. Based on this, we proposed a gradual approach and a set of recommendations to promote the development and use of publicly-accessible datasets in the region. These recommendations target potential actions by governments, researchers, policy makers and international organizations.

SUMMARY

We argue that the limited number of publicly-accessible datasets in the MENA region represents a lost opportunity for the evidence-based advancement of health systems in the region. The availability and use of publicly-accessible datasets would encourage policy makers in this region to base their decisions on solid representative data and not on estimates or small-scale studies; researchers would be able to exercise their expertise in a meaningful manner to both, policy makers and the public. The population of the MENA countries would exercise the right to benefit from locally- or regionally-based studies, versus imported and in 'best cases' customized ones. Furthermore, on a macro scale, the availability of regionally comparable publicly-accessible datasets would allow for the exploration of regional variations and benchmarking studies.