A Preliminary Report on the Prognostic Significance of Preoperative Brain Natriuretic Peptide and Postoperative Cardiac Troponin in Patients Undergoing Major Vascular Surgery

[The role of cardiac biomarkers in perioperative risk evaluation of noncardiac surgery patients-A summary of the ESAIC guidelines 2023]

BACKGROUND

The recently published ESAIC guidelines highlight the clinical value of cardiac troponins (cTn) and B‑type natriuretic peptides (BNP) for risk assessment in patients undergoing noncardiac surgery.

OBJECTIVE

Summary of the ESAIC guideline recommendations.

MATERIAL AND METHODS

The evidence for the recommendations was extracted from studies that investigated the perioperative role of cTn and BNP as prognostic factors, for risk prediction and for therapeutic guidance. To collate this evidence 12 relevant endpoints as well as risk benefit analyses of systematic screening were considered to issue the strength of the recommendations.

RESULTS

The body of evidence for these guidelines was based on 115 studies. The evidence varied significantly across the 12 predefined endpoints. Additionally, there was a gradient in evidence for the use of cTn and BNP as prognostic factors, for risk prediction and for therapeutic guidance. The guidelines issue a weak recommendation for the use of preoperative, postoperative and combined measurement of cTn as well as for preoperative BNP measurement to assess the prognosis. For risk prediction a weak recommendation was formulated for combined and postoperative cTn and preoperative BNP measurements. No recommendation could be given for the evidence on biomarkers as data were very limited.

CONCLUSION

Both cTn and BNP can be used as prognostic factors or to predict the risk for selected endpoints. Therapeutic interventions should not be guided by cardiac biomarker levels.

ESAIC focused guideline for the use of cardiac biomarkers in perioperative risk evaluation

BACKGROUND

In recent years, there has been increasing focus on the use of cardiac biomarkers in patients undergoing noncardiac surgery.

AIMS

The aim of this focused guideline was to provide updated guidance regarding the pre-, post- and combined pre-and postoperative use of cardiac troponin and B-type natriuretic peptides in adult patients undergoing noncardiac surgery.

METHODS

The guidelines were prepared using Grading of Recommendations Assessment Development and Evaluation (GRADE) methodology. This included the definition of critical outcomes, a systematic literature search, appraisal of certainty of evidence, evaluation of biomarker measurement in terms of the balance of desirable and undesirable effects including clinical outcomes, resource use, health inequality, stakeholder acceptance, and implementation. The panel differentiated between three different scopes of applications: cardiac biomarkers as prognostic factors, as tools for risk prediction, and for biomarker-enhanced management strategies.

RESULTS

In a modified Delphi process, the task force defined 12 critical outcomes. The systematic literature search resulted in over 25,000 hits, of which 115 full-text articles formed the body of evidence for recommendations. The evidence appraisal indicated heterogeneity in the certainty of evidence across critical outcomes. Further, there was relevant gradient in the certainty of evidence across the three scopes of application. Recommendations were issued and if this was not possible due to limited evidence, clinical practice statements were produced.

CONCLUSION

The ESAIC focused guidelines provide guidance on the perioperative use of cardiac troponin and B-type natriuretic peptides in patients undergoing noncardiac surgery, for three different scopes of application.

Postoperative elevated cardiac troponin levels predict all-cause mortality and major adverse cardiovascular events following noncardiac surgery: A dose-response meta-analysis of prospective studies

STUDY OBJECTIVE

To perform a dose-response meta-analysis for the association between postoperative myocardial injury (PMI) in noncardiac surgery and the risk of all-cause mortality or major adverse cardiovascular event (MACE).

DESIGN

Dose-response meta-analysis of prospective studies with weighted (WL) or generalized (GL) linear and restricted cubic spline (RCS) regression.

SETTING

Teaching hospitals.

PATIENTS

Adult patients undergoing noncardiac surgery.

INTERVENTIONS

No.

MEASUREMENTS

The primary outcome was all-cause mortality. The secondary outcome was MACE.

MAIN RESULTS

29 studies (53,518 patients) were included. The overall incidence of PMI was 26.0% (95% CI 21.0% to 32.0%). Compared to those without PMI, patients with PMI had an increased risk of all-cause mortality at short- (<12 months) (cardiac troponin[cTn]I: unadj OR 1.71,95%CI 1.22 to 2.41, P < 0.001; cTnT: unadj OR 2.33,95%CI 2.07 to 2.63, P < 0.001), and long-term (≥ 12 months) (cTnI: unadj OR 1.80, 95%CI 1.63 to 1.99; cTnT: unadj OR 1.47,95%CI 1.33 to 1.62) (All P < 0.001) follow-up. For MACE, the group with elevated values was associated with an increased risk (cTnI: unadj OR 1.98, 95% CI 1.13 to 3.47, P = 0.018; cTnT: unadj OR 2.29, 95% CI 1.88 to 2.79, P < 0.001). Dose-response analysis showed positive associations between PMI (per 1× upper reference limit[URL] increment) and all-cause mortality both at short- (unadj OR) (WL, OR 1.09, 95% CI 1.09 to 1.10; GL, OR 1.06, 95% CI 1.06 to 1.07; RCS in the range of 1-2× URL, OR = 2.43, 95%CI 2.25 to 2.62) and long-term follow-up (unadj HR) (WL, OR 1.16, 95% CI 1.14 to 1.17; GL, OR 1.15, 95% CI 1.13 to 1.16; RCS in the range of 1-2.75× URL, OR = 1.23, 95%CI 1.13 to 1.33), and MACE at longest follow-up (unadj OR) (WL: OR 1.53, 95% CI 1.49 to 1.57; GL: OR 1.46, 95% CI 1.42 to 1.50; RCS in the range of 1-2 x URL, OR = 3.10, 95%CI 2.51 to 3.81) (All P < 0.001). For mild cTn increase below URL, the risk of mortality increased with every increment of 0.25xURL (WL, OR 1.03, 95% CI 1.02 to 1.03; GL, OR 1.05, 95% CI 1.03 to 1.07; RCS in the range of 0-0.5 URL, OR = 9.41, 95% CI 7.41 to 11.95) (All P < 0.001).

CONCLUSIONS

This study shows positive WL or GL and RCS dose-response relationships between PMI and all-cause mortality at short (< 12 mons)- and long-term (≥ 12 mons) follow-up, and MACE at longest follow-up. For mild cTn increase below URL, the risk of mortality also increases even with every increment of 0.25× URL.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS₂, CHA₂DS₂-VASc, R₂CHADS₂, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Diastolic Dysfunction Is a Risk of Perioperative Myocardial Injury Assessed by High-Sensitivity Cardiac Troponin T in Elderly Patients Undergoing Non-Cardiac Surgery

BACKGROUND

High-sensitivity cardiac troponin T (hs-cTnT) is useful for detecting myocardial injury and is expected to become a prognostic marker in patients undergoing non-cardiac surgery. The aim of this pilot study evaluating the efficacy of β-blocker therapy in a perioperative setting (MAMACARI study) was to assess perioperative myocardial injury (PMI) in elderly patients with preserved ejection fraction (EF) undergoing non-cardiac surgery.Methods and Results:In this prospective observational cohort study of 151 consecutive patients with preserved EF and aged >60 years who underwent non-cardiac surgery, serum levels of hs-cTnT were measured before and on postoperative days 1 and 3 after surgery. PMI was defined as postoperative hs-cTnT >0.014 ng/mL and relative hs-cTnT change ≥20%. A total of 36 (23.8%) of the patients were diagnosed as having PMI. The incidence of a composite of cardiovascular events within 30 days after surgery, including myocardial infarction, stroke, worsening heart failure, atrial fibrillation and pulmonary embolism, was significantly higher in patients with PMI than in patients without PMI (odds ratio (OR) 9.25, P<0.001, 95% confidence interval (CI) 2.65-32.3). Multivariate analysis revealed that left ventricular diastolic dysfunction defined by echocardiography was independently associated with PMI (OR: 3.029, 95% CI: 1.341-6.84, P=0.008).

CONCLUSIONS

PMI is frequently observed in elderly patients undergoing non-cardiac surgery. Diastolic dysfunction is an independent predictor of PMI.

One-Year Mortality, Causes of Death, and Cardiac Interventions in Patients with Postoperative Myocardial Injury

BACKGROUND

To evaluate the role of routine troponin surveillance in patients undergoing major noncardiac surgery, unblinded screening with cardiac consultation per protocol was implemented at a tertiary care center. In this study, we evaluated 1-year mortality, causes of death, and consequences of cardiac consultation of this protocol.

METHODS

This observational cohort included 3224 patients ≥60 years old undergoing major noncardiac surgery. Troponin I was measured routinely on the first 3 postoperative days. Myocardial injury was defined as troponin I >0.06 μg/L. Regression analysis was used to determine the association between myocardial injury and 1-year mortality. The causes of death, the diagnoses of the cardiologists, and interventions were determined for different levels of troponin elevation.

RESULTS

Postoperative myocardial injury was detected in 715 patients (22%) and was associated with 1-year all-cause mortality (relative risk [RR] 1.4, P = 0.004; RR 1.6, P < 0.001; and RR 2.2, P < 0.001 for minor, moderate, and major troponin elevation, respectively). Cardiac death within 1 year occurred in 3%, 5%, and 11% of patients, respectively, in comparison with 3% of the patients without myocardial injury (P = 0.059). A cardiac consultation was obtained in 290 of the 715 patients (41%). In 119 (41%) of these patients, the myocardial injury was considered to be attributable to a predisposing cardiac condition, and in 111 patients (38%), an intervention was initiated.

CONCLUSIONS

Postoperative myocardial injury was associated with an increased risk of 1-year all-cause but not cardiac mortality. A cardiac consultation with intervention was performed in less than half of these patients. The small number of interventions may be explained by a low suspicion of a cardiac etiology in most patients and lack of consensus for standardized treatment in these patients.

An update on predictive biomarkers for major adverse cardiovascular events in patients undergoing vascular surgery

Cardiovascular complications signify a major cause of morbidity and mortality in patients undergoing vascular surgery adversely affecting both short- and long-term prognosis. During the last decade, unmet needs for a distinct cardiovascular risk assessment have led to an intensive research for establishment of biomarkers with sufficient predictive value. This literature review aims in examining the value of several biomarkers in predicting the incidence of major adverse cardiac events in vascular surgery patients. We reviewed the English language literature and analyzed the biomarkers as independent predictors or in correlation with other factors. We found several biomarkers showing a significant predictive value for a major adverse cardiovascular event in patients undergoing vascular surgery. These biomarkers can be used in clinical practice as outcome predictors, although sensitivity and specificity varies. Detection of subclinical cardiovascular damage may improve total risk estimation and facilitate clinical assessment of patients at risk for future cardiovascular events. The wide variety of sensitivity and specificity in predicting a MACE of these biomarkers exert the need for future trials in which these markers will be tested as adjunctive tools of cardiovascular risk estimation scoring systems.

Predicting the occurrence of major adverse cardiac events within 30 days of a vascular surgery: an empirical comparison of the minimum p value method and ROC curve approach using individual patient data meta-analysis

We aimed to compare the minimum p value method and the area under the receiver operating characteristics (ROC) curve approach to categorize continuous biomarkers for the prediction of postoperative 30-day major adverse cardiac events in noncardiac vascular surgery patients. Individual-patient data from six cohorts reporting B-type natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NTproBNP) were obtained. These biomarkers were dichotomized using the minimum p value method and compared with previously reported ROC curve-derived thresholds using logistic regression analysis. A final prediction model was developed, internally validated, and assessed for its sensitivity to clustering effects. Finally, a preoperative risk score system was proposed. Thresholds identified by the minimum p value method and ROC curve approach were 115.57 pg/ml (p < 0.001) and 116 pg/ml for BNP, and 241.7 pg/ml (p = 0.001) and 277.5 pg/ml for NTproBNP, respectively. The minimum p value thresholds were slightly stronger predictors based on our logistic regression analysis. The final model included a composite predictor of the minimum p value method’s BNP and NTproBNP thresholds [odds ratio (OR) = 8.5, p < 0.001], surgery type (OR = 2.5, p = 0.002), and diabetes (OR = 2.1, p = 0.015). Preoperative risks using the scoring system ranged from 2 to 49 %. The minimum p value method and ROC curve approach identify similar optimal thresholds. We propose to replace the revised cardiac risk index with our risk score system for individual-specific preoperative risk stratification after noncardiac nonvascular surgery.

B-type natriuretic peptide-guided therapy for perioperative medicine?

The recent guideline from the European Society of Cardiology and European Society of Anesthesiology recommended the use of B-type natriuretic peptide (BNP) as preoperative testing for high-risk cardiac patients undergoing non-cardiac surgery. In this article, the potential benefits, risks and details for implementing BNP testing in perioperative medicine are discussed. Review of four related lines of research including the use of BNP test for preoperative prognosis, BNP test for screening asymptomatic heart failure, BNP as prognostic test in asymptomatic, non-heart failure patients and using BNP for detecting silent myocardial ischaemia showed converging cut-off levels of BNP for risk stratification. BNP has better OR and relative risk in comparison with Revised Cardiac Risk Index (RCRI) in predicting perioperative cardiac risk. BNP-guided therapy can be low risk based on current evidence on non-surgical patients, including treating asymptomatic patients without heart failure to prevent cardiovascular complications. At present, there is lack of direct evidence supporting perioperative BNP testing. Further research with randomised controlled trials is needed to confirm the benefit of BNP-guided management. Preoperative BNP testing may be considered in patients with RCRI above 0 undergoing intermediate or high-risk surgery. BNP-guided therapy is likely a beneficial addition to perioperative medicine. Its combination with β-blocker titration, RCRI and perioperative cardiovascular monitoring can be a major advance in reducing cardiac risk resulting in a dynamic, individualised optimisation process.

Predictive value of plasma brain natriuretic peptide for postoperative cardiac complications--a systemic review and meta-analysis

BACKGROUND

We aimed to undertake a systematic review and meta-analysis of studies addressing perioperative natriuretic peptide (NP) levels to predict postoperative major adverse cardiac events (MACE) after major surgery.

METHODS

We searched MEDLINE and Embase with no language restrictions up to May 2013. The end points were major cardiac complications. We summarized test performance characteristics with the use of forest plots, hierarchical summary receiver operating characteristic curves, and bivariate random effects models.

RESULTS

Of the 662 retrieved articles, 24 studies satisfied the predefined eligibility criteria, including 5438 patients along with 712 (13.1%) events. After major surgery, the diagnostic odds ratio (DOR) of NP in predicting postoperative MACE was 14.3 (95% confidence interval [CI], 9.87-20.7) for overall population, 13.9 (8.43-22.8) for patients undergoing cardiac surgery, and 15.0 (8.84-25.5) for patients undergoing noncardiac surgery. The pooled sensitivity was 0.84 (95% CI, 0.79-0.88) and specificity was 0.76 (95% CI, 0.71-0.81). Postoperative measurement (DOR, 18.9; 7.68-46.3) was associated with higher predictive value than preoperative measurement (DOR, 13.6; 7.68-46.3). Results were similar for a subgroup with the composite outcome including mortality (DOR, 16.4; 10.6-25.5). B-type natriuretic peptide was associated with higher predictive accuracy (area under the summary receiver operating characteristic, 0.84; 0.81-0.87) than N-terminal pro-b-type natriuretic peptide (area under the summary receiver operating characteristic, 0.90; 0.87-0.92).

CONCLUSIONS

The existing literature suggests that perioperative NP testing have reasonable accuracy and can be useful in perioperative risk stratification. Natriuretic peptide testing has high rule-out value and low rule-in value for predicting postoperative MACE. Medical decisions should be made in the context of these characteristics.

Clinical use of ultrasensitive cardiac troponin I assay in intermediate- and high-risk surgery patients

Background. Cardiac troponin levels have been reported to add value in the detection of cardiovascular complications in noncardiac surgery. A sensitive cardiac troponin I (cTnI) assay could provide more accurate prognostic information. Methods. This study prospectively enrolled 142 patients with at least one Revised Cardiac Risk Index risk factor who underwent noncardiac surgery. cTnI levels were measured postoperatively. Short-term cardiac outcome predictors were evaluated. Results. cTnI elevation was observed in 47 patients, among whom 14 were diagnosed as having myocardial infarction (MI). After 30 days, 16 patients had major adverse cardiac events (MACE). Excluding patients with a final diagnosis of MI, predictors of cTnI elevation included dialysis, history of heart failure, transoperative major bleeding, and elevated levels of pre- and postoperative N-terminal pro-B-type natriuretic peptide (NT-proBNP). Maximal cTnI values showed the highest sensitivity (94%), specificity (75%), and overall accuracy (AUC 0.89; 95% CI 0.80–0.98) for postoperative MACE. Postoperative cTnI peak level (OR 9.4; 95% CI 2.3–39.2) and a preoperative NT-proBNP level ≥917 pg/mL (OR 3.47; 95% CI 1.05–11.6) were independent risk factors for MACE. Conclusions. cTnI was shown to be an independent prognostic factor for cardiac outcomes and should be considered as a component of perioperative risk assessment.

Acute myocardial infarctation in patients with critical ischemia underwent lower limb revascularization

BACKGROUND: Atherosclerosis is the main cause of peripheral artery occlusive disease (PAOD) of the lower limbs. Patients with PAOD often also have obstructive atherosclerosis in other arterial sites, mainly the coronary arteries. This means that patients who undergo infrainguinal bypass to treat critical ischemia have a higher risk of AMI. There are, however, few reports in the literature that have assessed this risk properly. OBJECTIVE: The aim of this study was to determine the incidence of acute myocardial infarction in patients who underwent infrainguinal bypass to treat critical ischemia of the lower limbs caused by PAOD. MATERIAL AND METHODS: A total of 64 patients who underwent 82 infrainguinal bypass operations, from February 2011 to July 2012 were studied. All patients had electrocardiograms and troponin I blood assays during the postoperative period (within 72 hours). RESULTS: There were abnormal ECG findings and elevated blood troponin I levels suggestive of AMI in five (6%) of the 82 operations performed. All five had conventional surgery. The incidence of AMI as a proportion of the 52 conventional surgery cases was 9.6%. Two patients died. CONCLUSION: There was a 6% AMI incidence among patients who underwent infrainguinal bypass due to PAOD. Considering only cases operated using conventional surgery, the incidence of AMI was 9.6%.

The prognostic value of pre-operative and post-operative B-type natriuretic peptides in patients undergoing noncardiac surgery: B-type natriuretic peptide and N-terminal fragment of pro-B-type natriuretic peptide: a systematic review and individual patient data meta-analysis

OBJECTIVES

The objective of this study was to determine whether measuring post-operative B-type natriuretic peptides (NPs) (i.e., B-type natriuretic peptide [BNP] and N-terminal fragment of proBNP [NT-proBNP]) enhances risk stratification in adult patients undergoing noncardiac surgery, in whom a pre-operative NP has been measured.

BACKGROUND

Pre-operative NP concentrations are powerful independent predictors of perioperative cardiovascular complications, but recent studies have reported that elevated post-operative NP concentrations are independently associated with these complications. It is not clear whether there is value in measuring post-operative NP when a pre-operative measurement has been done.

METHODS

We conducted a systematic review and individual patient data meta-analysis to determine whether the addition of post-operative NP levels enhanced the prediction of the composite of death and nonfatal myocardial infarction at 30 and ≥180 days after surgery.

RESULTS

Eighteen eligible studies provided individual patient data (n = 2,179). Adding post-operative NP to a risk prediction model containing pre-operative NP improved model fit and risk classification at both 30 days (corrected quasi-likelihood under the independence model criterion: 1,280 to 1,204; net reclassification index: 20%; p < 0.001) and ≥180 days (corrected quasi-likelihood under the independence model criterion: 1,320 to 1,300; net reclassification index: 11%; p = 0.003). Elevated post-operative NP was the strongest independent predictor of the primary outcome at 30 days (odds ratio: 3.7; 95% confidence interval: 2.2 to 6.2; p < 0.001) and ≥180 days (odds ratio: 2.2; 95% confidence interval: 1.9 to 2.7; p < 0.001) after surgery.

CONCLUSIONS

Additional post-operative NP measurement enhanced risk stratification for the composite outcomes of death or nonfatal myocardial infarction at 30 days and ≥180 days after noncardiac surgery compared with a pre-operative NP measurement alone.

Myocardial Injury After Noncardiac Surgery and its Association With Short-Term Mortality

Background—

To identify patients at risk for postoperative myocardial injury and death, measuring cardiac troponin routinely after noncardiac surgery has been suggested. Such monitoring was implemented in our hospital. The aim of this study was to determine the predictive value of postoperative myocardial injury, as measured by troponin elevation, on 30-day mortality after noncardiac surgery.

Methods and Results—

This observational, single-center cohort study included 2232 consecutive intermediate- to high-risk noncardiac surgery patients aged ≥60 years who underwent surgery in 2011. Troponin was measured on the first 3 postoperative days. Log binomial regression analysis was used to estimate the association between postoperative myocardial injury (troponin I level >0.06 μg/L) and all-cause 30-day mortality. Myocardial injury was found in 315 of 1627 patients in whom troponin I was measured (19%). All-cause death occurred in 56 patients (3%). The relative risk of a minor increase in troponin (0.07–0.59 μg/L) was 2.4 (95% confidence interval, 1.3–4.2; P <0.01), and the relative risk of a 10- to 100-fold increase in troponin (≥0.60 μg/L) was 4.2 (95% confidence interval, 2.1–8.6; P <0.01). A myocardial infarction according to the universal definition was diagnosed in 10 patients (0.6%), of whom 1 (0.06%) had ST-segment elevation myocardial infarction.

Conclusions—

Postoperative myocardial injury is an independent predictor of 30-day mortality after noncardiac surgery. Implementation of postoperative troponin monitoring as standard of care is feasible and may be helpful in improving the prognosis of patients undergoing noncardiac surgery.

Ascertainment of any and all neurologic and myocardial damage in carotid revascularization: the key to optimization?

The majority of carotid revascularization procedures performed at present are in asymptomatic patients. Since such procedures convey no immediate benefit, but rather protect from future hazard, optimization of procedural safety is mandatory. The authors focus their discussion on the methodologies that assess periprocedural myocardial damage and brain injury, as used in past clinical trials, from the fields of perioperative medicine and neurovascular imaging, and discuss methodologies to reduce both events in carotid revascularization.

[Cardiac biomarkers in perioperative risk stratification]

OBJECTIVES

The field of new cardiac biomarkers has triggered physicians' enthusiasm because of their potential diagnostic and prognostic values for routine clinical practice in the surgical setting. The objective of the present article is to review the role of new cardiac biomarkers and their potential additive clinical value in predicting short- and long-term risk following cardiac and non-cardiac surgery.

DATA SOURCES

A PubMed(®) database research in English and French languages published until June 2010. Keywords were cardiac biomarkers, troponins, cardiac troponin I (cTnI), natriuretic peptides, B-type natriuretic peptide (BNP), C-reactive protein (CRP), multiple markers approach, risk stratification, clinical risk scores.

DATA SYNTHESIS

Numerous publications deal with the diagnostic and prognostic values of new cardiac biomarkers in cardiac and non-cardiac surgical settings and provide an increasing evidence of their interest, validating different hierarchical steps which are mandatory before recommending a wide use of biomarkers for routine practice. Even if the first studies demonstrating an additional prognostic value of serum postoperative cTnI and/or preoperative BNP when compared with clinical predictive models are now available, we still lack data concerning an actual positive impact of new biomarkers measurements on clinical decision making or practice, as well as patient care and outcome.

CONCLUSIONS

While use of new cardiac biomarkers in the perioperative period appears to be a simple and objective tool for risk stratification at the bedside, we still need to remain cautious concerning their additional clinical value on existing predictive models for routine practice.

Perioperative cardiac damage in vascular surgery patients

BACKGROUND

Patients undergoing vascular surgery are at increased risk for developing cardiac complications. Majority of patients with perioperative myocardial damage are asymptomatic. Our objective is to review the available literature addressing the prevalence and prognostic implications of perioperative myocardial damage in vascular surgery patients.

METHODS

An Internet-based literature search was performed using MEDLINE to identify all published reports on perioperative myocardial damage in vascular surgery patients. Only those studies published from 2000 to 2010 evaluating myocardial damage using troponin I or T, with or without symptoms of angina pectoris were included.

RESULTS

Thirteen studies evaluating the prevalence of perioperative myocardial ischaemia or infarction were included in the study. The incidence of perioperative myocardial ischaemia ranged from 14% to 47% and the incidence of perioperative myocardial infarction ranged from 1% to 26%. In addition, 10 studies evaluating the prognostic value of perioperative myocardial ischaemia towards postoperative mortality or the occurrence of major adverse cardiac events were included. In the retrieved studies, hazard ratios varied from 1.9 to 9.0.

CONCLUSION

The high prevalence and asymptomatic nature of perioperative myocardial damage, combined with a substantial influence on postoperative mortality of vascular surgery patients, underline the importance of early detection and adequate management of perioperative myocardial damage. This article provides an extended overview regarding the prevalence and prognostic value of perioperative myocardial ischaemia and infarction in vascular surgery patients. In addition, treatment options to reduce the risk of perioperative myocardial damage are provided based on the current available literature.

[Non-cardiac surgery in patients with cardiac disease]

BACKGROUND

Patients with cardiac disease have a higher incidence of cardiovascular events after non-cardiac surgery than those without such disease. This paper provides an overview of perioperative examinations and treatment.

MATERIAL AND METHODS

Own experience and systematic literature search through work with European guidelines constitute the basis for recommendations given in this article.

RESULTS

Beta-blockers should not be discontinued before surgery. High-risk patients may benefit from beta-blockers administered before major non-cardiac surgery. Slow dose titration is recommended. Echocardiography should be performed before preoperative beta-blockade to exclude latent heart failure. Statins should be considered before elective surgery and coronary intervention (stenting or surgery) before high-risk surgery. Otherwise, interventions should be evaluated irrespective of planned non-cardiac surgery. Patients with unstable coronary syndrome should only undergo non-cardiac surgery on vital indications. Neuraxial techniques are optimal for postoperative pain relief and thus for postoperative mobilization. Thromboprophylaxis is important, but increases the risk of epidural haematoma and requires systematic follow-up with respect to diagnostics and treatment.

INTERPRETATION

Little evidence supports the use of different anaesthetic methods in cardiac patients that undergo non-cardiac surgery than in other patients. Stable circulation, sufficient oxygenation, good pain relief, thromboprophylaxis, enteral nutrition and early mobilization are important factors for improving the perioperative course. Close cooperation between anaesthesiologist, surgeon and cardiologist improves logistics and treatment.

Natriuretic Peptides and Assessment of Cardiovascular Disease Risk in Asymptomatic Persons

Current tools for cardiovascular disease (CVD) risk assessment in asymptomatic individuals are imperfect. Preventive measures aimed only at individuals deemed high risk by current algorithms neglect large numbers of low-risk and intermediate-risk individuals who are destined to develop CVD and who would benefit from early and aggressive treatment. Natriuretic peptides have the potential both to identify individuals at risk for future cardiovascular events and to help detect subclinical CVD. Choosing the appropriate subpopulation to target for natriuretic peptide testing will help maximize the performance and the cost effectiveness. The combined use of multiple risk markers, including biomarkers, genetic testing, and imaging or other noninvasive measures of risk, offers promise for further refining risk assessment algorithms. Recent studies have highlighted the utility of natriuretic peptides for preoperative risk stratification; however, cost effectiveness and outcomes studies are needed to affirm this and other uses of natriuretic peptides for cardiovascular risk assessment in asymptomatic individuals.