Preoperative Statin Therapy and Troponin T Predict Early Complications of Coronary Artery 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.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Statin loading in cardiovascular surgery: never too early to treat

PURPOSE OF REVIEW

The effects of statin loading before, during or after vascular interventions on cardiovascular and renal outcomes are discussed. Furthermore, the selection of optimal statin type and dose, according to current evidence or guidelines, is considered. The importance of treating statin intolerance and avoiding statin discontinuation is also discussed.

RECENT FINDINGS

Statin loading has been shown to beneficially affect cardiovascular outcomes, total mortality and/or contrast-induced acute kidney injury, in patients undergoing vascular procedures such as percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), carotid endarterectomy (CEA), carotid artery stenting, endovascular aneurysm repair, open abdominal aortic aneurysms (AAA) repair and lower extremities vascular interventions. High-dose statin pretreatment is recommended for PCI and CABG according to current guidelines. Statin discontinuation should be avoided during acute cardiovascular events and vascular interventions; adequate measures should be implemented to overcome statin intolerance.

SUMMARY

Statin loading is an important clinical issue in patients with cardiac and noncardiac vascular diseases, including carotid artery disease, peripheral artery disease and AAA, undergoing vascular interventions. Cardiologists and vascular surgeons should be aware of current evidence and implement guidelines in relation to statin loading, discontinuation and intolerance.

Could Short-Term Perioperative High-Dose Atorvastatin Offer Antiarrhythmic and Cardio-Protective Effects in Rheumatic Valve Replacement Surgery?

OBJECTIVES

To evaluate the role of prophylactic high-dose atorvastatin for prevention of postoperative atrial fibrillation (POAF), inflammatory response attenuation, and myocardial protection after valve replacement cardiac surgery.

DESIGN

Randomized controlled trial.

SETTING

Assiut University Hospitals.

PARTICIPANTS

Sixty-four adult patients undergoing cardiac valve replacement surgery.

INTERVENTIONS

The participants were equally divided into 2 groups. Group S received 80 mg of atorvastatin (oral tablets), 12 and 2 hours preoperatively, and on the 2nd, 3rd, 4th, and 5th postoperative days. Control group C received placebo at the same time periods.

MEASUREMENTS

The incidence of POAF, postoperative white blood cell count, serum C-reactive protein, interleukin 6, and troponin I.

MAIN RESULTS

Group S patients showed a lower incidence of POAF compared with the placebo group (p = 0.031). The white blood cell count showed significant reductions in group S compared with group C on the second, third, fourth, and fifth postoperative days. The C-reactive protein level showed significant reductions on the third, fourth, and fifth postoperative days in group S compared with group C (p = 0.001, 0.001, and 0.001, respectively). The serum level of interleukin 6 showed a significant reduction on the fifth postoperative day in group S compared with group C (p = 0.001). There was no significant difference between the 2 groups regarding the troponin I level and inotropic score.

CONCLUSION

Prophylactic use of high dose atorvastatin can decrease the incidence of POAF and attenuate the inflammatory process in adult patients undergoing isolated rheumatic cardiac valve replacement surgery.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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 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.

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.

The Effect of Statins and Other Cardiovascular Medication on Ischemia-Reperfusion Damage in a Human DIEP Flap Model: Theoretical and Epidemiological Considerations

Background. Statins and other cardiovascular medication possess antioxidant capacity. It was examined whether chronic use of these medications protects from the development of ischemia-reperfusion (I/R) related complications after DIEP (Deep Inferior Epigastric Perforator Free Flap) surgery. This paper contains a literature study on the antioxidant working mechanisms of these drugs. Methods. Medical information of 134 DIEP patients (173 flaps) was studied from their medical files. Patient and operative characteristics were registered, as well as I/R related complications. Results. Of the group that didnot use statins, 16.3% developed complications versus 30.8% amongst patients that did use these drugs (P = 0.29). Amongst patients that chronically use other cardiovascular medication, 26.8% developed I/R related complications versus 14.4% of the patients without medication (P = 0.10). Conclusions. Chronic use of statins or other cardiovascular medication didnot decrease the occurrence of I/R related complications after DIEP surgery. Therefore, research should be aimed at evaluating short-term pre-treatment with statins.

The effect of acute administration of statins on coronary microcirculation during the pre-revascularization period in patients with myocardial infraction

The beneficial effects of statin pretreatment as well as of staccato reperfusion (SR) on myocardium have been demonstrated in patients undergoing cardiac interventions. In this study, we compared the effects of the acute statin administration prior to percutaneous coronary intervention (PCI) with the effects of staccato or abrupt reperfusion on coronary microcirculation in patients with myocardial infarction (MI).

METHODS

We randomly assigned 47 patients who had ST-elevation or non-ST-elevation MI 48 h prior to PCI, into three groups: staccato reperfusion (consisting of 6 periods of 10-s balloon inflation/deflation) plus statin therapy (SRSG), statin therapy plus abrupt reperfusion (SG), and abrupt reperfusion alone (ARG). Myocardial contrast echocardiography (MCE) was performed to assess the blood volume (A), velocity (β) and flow (A × β) of the segments associated with the PCI-treated artery the day following intervention and 30 days after. LV end-diastolic (EDV) and systolic volumes (ESVs), wall motion score index (WMSI) were evaluated.

RESULTS

Compared to ARG, SRSG and SG resulted in a greater improvement in A, β and A × β (F = 20.6, p < 0.001 for A, F = 3.5, p = 0.03 for β and F = 11.3, p < 0.001 for A × β for the overall effect of intervention) as well as a greater decrease of WMSI, EDV and ESV (p < 0.01) one month post-PCI. The changes of all echocardiography markers were greater in SRSG than SG (p < 0.01). The % changes in ESV correlated with the corresponding % changes in MCE indices in SRSG and SG (p < 0.05).

CONCLUSION

The acute statin administration prior to reperfusion either alone or in synergy with staccato reperfusion ameliorates coronary microcirculatory dysfunction in patients with myocardial infarction.

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.

Atorvastatin pretreatment diminishes the levels of myocardial ischemia markers early after CABG operation: an observational study

Background

Statin pretreatment has been associated with a decrease in myocardial ischemia markers after various procedures and cardiovascular events. This study examined the potential beneficial effects of preoperative atorvastatin treatment among patients undergoing on-pump CABG operation.

Methods

Twenty patients that had received atorvastatin treatment for at least 15 days prior to the operation and 20 patients who had not received any antihyperlipidemic agent prior to surgery were included in this study. CK-MB and troponin I levels were measured at baseline and 24 hours after the operation. Perioperative variables were also recorded.

Results

Twenty-four hours after the operation, troponin I and CK-MB levels were significantly lower in the atorvastatin group: for CK-MB levels, 12.9 ± 4.3 versus 18.7 ± 7.4 ng/ml, p = 0.004; for troponin I levels, 1.7 ± 0.3 versus 2.7 ± 0.7 ng/ml, p < 0.001. In addition, atorvastatin use was associated with a decrease in the duration of ICU stay.

Conclusions

Preoperative atorvastatin treatment results in significant reductions in the levels of myocardial injury markers early after on-pump CABG operation, suggesting a reduction in perioperative ischemia in this group of patients. Further studies are needed to elucidate the mechanisms of these potential benefits of statin pretreatment.

Perioperative statin therapy is associated with a significant and dose-dependent reduction of adverse cardiovascular outcomes after coronary artery bypass graft surgery

OBJECTIVE

The aim of this study was to determine whether perioperative statin therapy was associated with a dose-dependent decrease in adverse cardiovascular events after coronary artery bypass graft (CABG) surgery.

DESIGN

A prospective observational study.

SETTING

A cardiovascular anesthesia unit in a university hospital.

PARTICIPANTS

Four hundred eighteen consecutive patients undergoing CABG surgery between October 2004 and October 2005.

INTERVENTIONS

Patients were divided in 2 groups depending on whether their preoperative treatment included statins or not. In patients receiving statins, high- and low-dose regimens were respectively defined as a regimen recognized to induce a theoretic reduction of low-density lipoprotein cholesterol level equal to 45% (n = 87) or <45% (n = 258). In treated patients, statin therapy was maintained until the day of surgery and was restarted soon thereafter.

MEASUREMENTS AND MAIN RESULTS

The measured endpoint was adverse in-hospital cardiovascular outcomes including heart failure and/or malignant arrhythmia and/or cardiac death. Stepwise logistic regression and a multivariate analysis of propensity-matched cohort were used for analysis of the findings. After adjustment for propensity score, statin therapy was found to produce a significant reduction in cardiovascular outcomes (odds ratio = 0.56; 95% confidence interval [CI], 0.32-0.96, p < 0.05). By using multivariate analysis, the odds ratio for cardiovascular outcomes in patients receiving high-dose statins compared with those treated by low-dose statins was 0.62 (95% CI, 0.41-0.93; p < 0.05).

CONCLUSION

Statin therapy is associated with a significant and dose-dependent reduction in adverse cardiovascular events after CABG surgery. However, further randomized trials still require confirming a causal association between statins and better postoperative outcomes and evaluating the tolerance of such perioperative therapy.

Predictive value of C-reactive protein for major postoperative complications following off-pump coronary artery bypass surgery: prospective and observational trial

BACKGROUND

To prospectively investigate the predictive value of the preoperative C-reactive protein (CRP) concentration for major postoperative complications following off-pump coronary artery bypass (OPCAB) surgery.

METHODS AND RESULTS

From January 2007 to December 2007, 185 consecutive patients scheduled for elective OPCAB surgery were allocated to a low-CRP group (n=137, CRP <0.3 mg/dl) and a high-CRP group (n=48, CRP > or = 0.3 mg/dl). The incidence of major postoperative complications, defined as postoperative myocardial infarction, and 5 major morbidity endpoints including permanent stroke, renal dysfunction, any cardiac surgery reoperation, ventilation for more than 48 h, and deep sternal wound infection were assessed and compared. Multivariate logistic regression was used to determine the predictors of major postoperative complications. Patients in the high-CRP group had a significantly higher overall incidence of major postoperative complications, particularly renal dysfunction. In the multivariate logistic regression model, adjusting all the significant univariate predictors, baseline CRP >0.3 mg/dl and preoperative chronic renal failure (CRF) remained as significant independent predictors of major postoperative complications.

CONCLUSIONS

Elevated preoperative CRP level and/or preoperative CRF indicate increased risk of developing major postoperative complications, particularly acute postoperative renal dysfunction in patients undergoing OPCAB surgery.

Pre-Operative Atorvastatin Therapy to Decrease the Systemic Inflammatory Response after Coronary Artery Bypass Grafting

The effect of pre-operative atorvastatin on systemic inflammatory response syndrome (SIRS), often seen after coronary artery bypass grafting (CABG) was evaluated in 40 patients undergoing elective CABG. Patients were divided into two groups: group I (pre-operative LDL cholesterol ≤ 100 mg/dl; n = 20) received 20 mg/day atorvastatin for at least 15 days pre-operatively; group II (pre-operative LDL cholesterol < 100 mg/dl; n = 20) did not receive antihyperlipidaemic agents. All patients underwent CABG with cardiopulmonary bypass. Blood samples were taken pre-operatively and 24 h post-operatively. There were no significant differences between the two groups in terms of demographic, pre-operative or operative parameters. At 24 h post-operatively, median high-sensitivity C-reactive protein and mean interleukin-6 levels were significantly lower in group I compared with group II. There were no other significant differences in postoperative parameters between the two groups, except for duration of stay in the intensive care unit, which was shorter in group I patients. In conclusion, pre-operative atorvastatin treatment in patients undergoing elective CABG decreased inflammation parameters and could be effective in preventing SIRS.

Impact of preoperative statin therapy on adverse postoperative outcomes in patients undergoing cardiac surgery: a meta-analysis of over 30,000 patients

AIMS

To determine the strength of evidence for preoperative statin use for prevention of adverse postoperative outcomes in patients undergoing cardiac surgery.

METHODS AND RESULTS

After literature search in major databases, 19 studies were identified [three RCT (randomized prospective clinical trials), 16 observational] that reported outcomes of 31 725 cardiac surgery patients with (n = 17 201; 54%) or without (n = 14 524; 46%) preoperative statin therapy. Outcomes that were analysed included early all-cause mortality (30-day mortality), myocardial infarction (MI), atrial fibrillation (AF), stroke and renal failure. Odds ratio (OR) with 95% confidence intervals (95%CI) were reported using fixed or random effect models and publication bias was assessed. Preoperative statin therapy resulted in a 1.5% absolute risk reduction (2.2 vs. 3.7%; P < 0.0001) and 43% odds reduction for early all-cause mortality (OR 0.57; 95%CI: 0.49-0.67). A significant reduction (P < 0.01) in statin pretreated patients was also observed for AF (24.9 vs. 29.3%; OR 0.67, 95%CI: 0.51-0.88), stroke (2.1 vs. 2.9%, OR 0.74, 95%CI: 0.60-0.91), but not for MI (OR 1.11; 95%CI: 0.93-1.33) or renal failure (OR 0.78, 95%CI: 0.46-1.31). Funnel plot and Egger's regression analysis (P = 0.60) excluded relevant publication bias.

CONCLUSION

Our meta-analysis provides evidence that preoperative statin therapy exerts substantial clinical benefit on early postoperative adverse outcomes in cardiac surgery patients, but underscores the need for RCT trials.

Pretreatment with statins may reduce cardiovascular morbidity and mortality after elective surgery and percutaneous coronary intervention: clinical evidence and possible underlying mechanisms

After Murry et al (Circulation 1986;74:1124) described ischemic preconditioning in 1986, numerous pharmacologic agents with effects simulating ischemic preconditioning have been identified. With the exception of beta-blockers, most such agents have no proven clinical benefit in the setting of myocardial ischemia. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been consistently demonstrated to reduce myocardial injury, morbidity, and mortality in the clinical setting, both perioperatively and after percutaneous coronary intervention. Although the precise mechanism underlying their additional protective effect is not yet fully understood, it appears to be immediate in action and independent of cholesterol lowering. Experimental data from several animal models of ischemia and reperfusion have demonstrated an infarct size reduction with prior statin administration. At the cellular level, statins activate the phosphoinositol-3 kinase and Akt signaling cascade. Statins also increase expression and activity of endothelial nitric oxide synthase, inducible nitric oxide synthase, ecto-5'-nucleotidase, cyclooxygenase-2, and other prostaglandin synthesis pathway enzymes. However, when given by oral route to animals, relatively high dose of statins is needed to exert maximal protective effect. Understanding the underlying mechanism may enable to maximize the protective effect by using drug combination with synergistic activity and to avoid medications that may interfere with the protective effect of statins (ie, selective and nonselective cyclooxygenase-2 inhibition). Future clinical applications include preoperative and periprocedural risk reduction.

CRP, IL-6 and endothelin-1 levels in patients undergoing coronary artery bypass grafting. Do preoperative inflammatory parameters predict early graft occlusion and late cardiovascular events?

BACKGROUND

Inflammation is a major contributor to atherosclerotic vascular disease. Inflammatory parameters such as C-reactive protein (CRP) and Interleukin-6 (IL-6) have been shown to be strong predictors of cardiovascular events. The association between preoperative inflammatory parameters and early graft occlusion as well as cardiovascular events after coronary artery bypass grafting (CABG) has not, however, been fully elucidated. The aims of the present study were to prospectively investigate the prognostic value of the inflammatory parameters IL-6, CRP, and endothelin (ET-1) to predict early graft occlusion as well as late cardiovascular events after CABG.

METHODS

In the present study 99 patients undergoing CABG because of stable angina pectoris due to significant coronary artery disease were prospectively included. Coronary angiography was repeated 3 months after CABG in 81 patients in order to evaluate early graft occlusion. Blood samples were collected before CABG in all patients. Patients were followed up for a median of 5 (3-7) years after CABG.

RESULTS

Twenty-five patients (31%) had one or more occluded grafts at the 3-month control coronary angiography. The patients with occluded grafts had higher preoperative CRP and IL-6 levels in plasma [CRP 2.22 (1.11-4.47) mg/L vs. 1.23 (0.71-2.27) mg/L P=0.03] and [IL-6 2.88 (1.91-5.94) pg/mL vs. 2.15 (1.54-3.14) pg/mL P=0.006]. There were 23 late cardiovascular events among the 99 patients during the follow-up. Patients experiencing late cardiovascular events had higher preoperative IL-6 levels than those without late cardiovascular events [4.13 (1.83-5.87) pg/mL vs. 2.08 (1.53-2.29) pg/mL, P=0.002] whereas CRP levels did not differ significantly between the two groups [1.5 (0.79-4.41) mg/L vs. 1.33 (0.74-2.48) mg/L, P=0.41]. Looking at IL-6, a cut off value more than 3.8 pg/ml was associated with a significant higher risk for an early graft occlusion (P=0.04) and late cardiovascular events (P=0.00003). Preoperative endothelin-1 did not predict early graft occlusions or late cardiovascular events.

CONCLUSIONS

Raised preoperative IL-6 levels are predictors of both early graft occlusion and late cardiovascular events after CABG. Elevated preoperative CRP levels can predict early graft occlusion after CABG. Endothelin did not differ between the two groups.

Review article: The role of statins in reducing perioperative cardiac risk: physiologic and clinical perspectives

PURPOSE

To review the pathobiology and clinical implications of coronary vulnerable atherosclerotic plaques (VAPs), to discuss the role of statin therapy in VAP stabilization, and the potential benefits of perioperative statin therapy (PST) in reducing perioperative risk of acute coronary syndromes (ACSs).

SOURCE

MEDLINE search using "perioperative", "cardiac morbidity", "atherosclerosis", "vulnerable plaque", "statins" and combinations of these terms as keywords. The reference lists of relevant articles were further reviewed to identify additional citations.

PRINCIPAL FINDINGS

The nonstenotic, yet rupture-prone VAP causes most myocardial infarctions (MIs) and other ACSs, both in the nonsurgical and surgical patients. Large clinical trials in both primary and secondary prevention and in patients with ACSs have demonstrated that statin therapy will reduce cardiovascular morbidity and mortality across a broad spectrum of patient subgroups. These trials also suggest, and laboratory investigations establish, that statins possess favourable vascular effects independent of cholesterol reduction. Statins appear to interfere specifically with the pathophysiologic mechanisms implicated in atherothrombotic disease. Statins reduce vascular inflammation, improve endothelial function, stabilize VAPs, and reduce platelet aggregability and thrombus formation. Recent studies have shown that PST is associated with a reduced incidence of perioperative and long-term cardiovascular complications in high-risk patients. Combined therapy with statins and ss-blockers is a conceptually valid strategy targeting critical steps in the pathogenesis of an ACS.

CONCLUSION

Emerging evidence for the efficacy and safety of PST is promising, especially when combined with ss-blocker therapy in patients at highest risk. Confirmation of this early evidence awaits the results of ongoing and future prospective randomized controlled trials.