Perioperative troponin surveillance in major noncardiac surgery: a narrative review

Personalised perioperative dosing of ivabradine in noncardiac surgery: a single-centre, randomised, placebo-controlled, double-blind feasibility pilot trial

BACKGROUND

Perioperative myocardial injury after noncardiac surgery is associated with postoperative mortality. Heart rate (HR) is an independent risk factor for perioperative myocardial injury. In this pilot trial we tested the feasibility of a randomised, placebo-controlled trial of personalised HR-targeted perioperative ivabradine.

METHODS

This was a single-centre, randomised, placebo-controlled, double-blind, parallel group, feasibility pilot trial conducted at Geneva University Hospitals. We included patients ≥75 yr old or ≥45 yr old with cardiovascular risk factors planned for intermediate- or high-risk surgery. Patients were randomised to receive ivabradine (2.5, 5.0, or 7.5 mg) or placebo according to their HR, twice daily, from the morning of surgery until postoperative day 2. Primary outcomes were appropriate dosage and blinding success rates.

RESULTS

Between October 2020 and January 2022, we randomised 78 patients (recruitment rate of 1.3 patients week-1). Some 439 of 444 study drug administrations were adequate (99% appropriate dosage rate). The blinding success rate was 100%. There were 137 (31%) administrations of Pill A (placebo in both groups for HR ≤70 beats min-1). Nine (11.5%) patients had a high-sensitive cardiac troponin T elevation ≥14 ng L-1 between any two measurements. The number of bradycardia episodes was eight in the placebo group and nine in the ivabradine group.

CONCLUSIONS

This pilot study demonstrates the feasibility of, and provides guidance for, a future trial testing the efficacy of personalised perioperative ivabradine. Future studies should include patients at higher risk of cardiac complications.

CLINICAL TRIAL REGISTRATION

NCT04436016.

Visualising myocardial injury after noncardiac surgery: a case series using postoperative cardiovascular MRI

Myocardial injury after noncardiac surgery (MINS) and perioperative myocardial injury are associated with increased morbidity and mortality. Both are diagnosed by a perioperative increase in troponin, yet there is controversy if MINS is a genuine myocardial insult. We applied postoperative cardiovascular magnetic resonance T2 mapping techniques to visualise acute myocardial injury (i.e. oedema) in six patients with multiple cardiovascular risk factors who underwent aortic surgery. The burden of myocardial oedema was substantially higher in four patients with elevated troponin qualifying for MINS, compared with patients without MINS. The data and images suggest that MINS represents genuine myocardial injury.

ESAIC focused guideline for the use of cardiac biomarkers in perioperative risk evaluation: Endorsement by the Scandinavian Society of Anaesthesiology and Intensive Care Medicine

BACKGROUND

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline "ESAIC focused guideline for the use of cardiac biomarkers in perioperative risk evaluation." The guideline can provide guidance to Nordic anaesthesiologists on the perioperative use of cardiac biomarkers in patients undergoing non-cardiac surgery.

To rule-in, or not to falsely rule-out, that is the question: evaluation of hs-cTnT EQA performance in light of the ESC-2020 guideline

OBJECTIVES

To accurately evaluate non-ST-elevated acute cardiac syndrome (NSTE-ACS), the quality of high-sensitive cardiac troponin (hs-cTn) assays is of vital importance. The 2020 revision of the NSTE-ACS guideline includes clinical decision-limits (CDL's) to both rule-in and rule-out NSTE-ACS for most commercially available platforms, providing both 0/1 h and 0/2 h delta limits. Our study evaluated whether laboratories are able to meet the analytical performance specifications for imprecision (APS) for hs-cTnT.

METHODS

Results from external quality assurance (EQA) in commutable samples were used to evaluate the current and historic performance of analyzers. The performance of analyzers that either passed or failed to comply with 0/1 h-APS were used on a real-world dataset of first hs-cTnT-values to simulate 10.000 samples of t=0, t=1 and t=2 h values with multiple delta's for all relevant CDL's. We compared the simulated values to the input values to obtain the percentage of aberrant results simulated.

RESULTS

The majority of analyzers complies with APS for rule-in in 2022 (0/1 h: 90.4 % and 0/2 h: 100 %), compliance for the 0/1 h rule-out is still far from optimal (0/1 h: 30.7 %, 0/2 h: 75.4 %), with improving compliance over the past years (rule-in p=<0.0001, rule-out p=0.011, χ2). Whilst 0/1 h-APS-passing analyzers have a minute risk to falsely rule-out patients whom should be ruled-in (0.0001 %), failing performance increases this risk to 2.1 % upon using 0/1 h CDL's. Here, adopting 0/2 h CDL's is favorable (0.01 %).

CONCLUSIONS

Laboratories that fail to meet hs-cTnT 0/1 h-APS should improve their performance to the required and achievable level. Until performance is reached clinics should adopt the 0/2 h CDL's.

Pathophysiological mechanisms underlying increased circulating cardiac troponin in noncardiac surgery: a narrative review

Assay-specific increases in circulating cardiac troponin are observed in 20-40% of patients after noncardiac surgery, depending on patient age, type of surgery, and comorbidities. Increased cardiac troponin is consistently associated with excess morbidity and mortality after noncardiac surgery. Despite these findings, the underlying mechanisms are unclear. The majority of interventional trials have been designed on the premise that ischaemic cardiac disease drives elevated perioperative cardiac troponin concentrations. We consider data showing that elevated circulating cardiac troponin after surgery could be a nonspecific marker of cardiomyocyte stress. Elevated concentrations of circulating cardiac troponin could reflect coordinated pathological processes underpinning organ injury that are not necessarily caused by ischaemia. Laboratory studies suggest that matching of coronary artery autoregulation and myocardial perfusion-contraction coupling limit the impact of systemic haemodynamic changes in the myocardium, and that type 2 ischaemia might not be the likeliest explanation for cardiac troponin elevation in noncardiac surgery. The perioperative period triggers multiple pathological mechanisms that might cause cardiac troponin to cross the sarcolemma. A two-hit model involving two or more triggers including systemic inflammation, haemodynamic strain, adrenergic stress, and autonomic dysfunction might exacerbate or initiate acute myocardial injury directly in the absence of cell death. Consideration of these diverse mechanisms is pivotal for the design and interpretation of interventional perioperative trials.

Clinical features that predict the mortality risk in older patients with Omicron pneumonia: the MLWAP score

In December 2022, the Chinese suffered widespread Omicron of SARS-CoV-2 with variable symptom severity and outcome. We wanted to develop a scoring model to predict the mortality risk of older Omicron pneumonia patients by analyzing admission data. We enrolled 227 Omicron pneumonia patients aged 60 years and older, admitted to our hospital from December 15, 2022, to January 16, 2023, and divided them randomly into a 70% training set and a 30% test set. The former were used to identify predictors and develop a model, the latter to verify the model, using the area under the receiver operating characteristic curve (AUC), the Hosmer-Lemeshow goodness-of-fit test, a calibration curve to test its performance and comparing it to the existing scores. The MLWAP score was calculated based on a multivariate logistic regression model to predict mortality with a weighted score that included immunosuppression, lactate ≥ 2.4, white blood cell count ≥ 6.70 × 109/L, age ≥ 77 years, and PaO2/FiO2 ≤ 211. The AUC for the model in the training and test sets was 0.852 (95% CI, 0.792-0.912) and 0.875 (95% CI, 0.789-0.961), respectively. The calibration curves showed a good fit. We grouped the risk scores into low (score 0-7 points), medium (8-10 points), and high (11-13 points). This model had a sensitivity of 0.849, specificity of 0.714, and better predictive ability than the CURB-65 and PSI scores (AUROC = 0.859 vs. 0.788 vs. 0.801, respectively). The MLWAP-mortality score may help clinicians to stratify hospitalized older Omicron pneumonia patients into relevant risk categories, rationally allocate medical resources, and reduce the mortality.

Effect of a national guideline on postoperative troponin surveillance: a retrospective cohort study

PURPOSE

We aimed to evaluate the effect of the 2017 Canadian Cardiovascular Society (CCS) guidelines on troponin surveillance after noncardiac surgery.

METHODS

This was a single-centre, retrospective, observational study. Patients aged 40 yr or older undergoing intermediate- to high-risk elective noncardiac surgery between 2016 and 2021 were included. We compared the number and percentage of troponin tests ordered before and after the guidelines were published and compared patient characteristics, specifically cardiovascular comorbidity, using odds ratio's (OR) with 95% confidence intervals (CIs). Outcomes were myocardial injury, myocardial infarction (MI), and in-hospital mortality.

RESULTS

The cohort included 36,386 patients and the median age was 63 yr. Between 2016 and 2018, troponin surveillance was done in 2,461 (13%) of the 19,046 patients, compared with 2,398 (14%) of the 17,340 patients who had surgery between 2019 and 2021 (OR, 1.08; 95% CI, 1.02 to 1.15). Patients who had surgery in the second period had less cardiovascular comorbidity; the adjusted OR for troponin surveillance was 1.14 (95% CI, 1.07 to 1.21). In the two periods, troponin was elevated in 561 (2.9%) and 470 (2.7%) patients, an MI was documented in 54 (0.3%) and 36 (0.2%) patients, and 95 (0.5%) and 73 (0.4%) patients died, respectively. After adjustment for baseline differences in the two periods, the ORs for MI and mortality were 0.83 (95% CI, 0.54 to 1.27) and 0.88 (95% CI, 0.64 to 1.19), respectively.

CONCLUSION

Although the odds of troponin ordering were slightly but significantly higher after publication of the CCS guidelines, the odds for detecting an MI and for mortality did not change.

Perioperative myocardial injury is associated with increased postoperative non-cardiac complications in patients undergoing vascular surgery: a post hoc analysis of a randomised clinical pilot trial

BACKGROUND

Elevated cardiac biomarkers, such as high-sensitivity cardiac Troponin T and N-terminal pro-B-type natriuretic peptide improve the prediction of major adverse cardiac events. However, very few trials have investigated the association between perioperative cardiac injury and non-cardiac complications. The primary aim of this study was to determine the association between peri-operative myocardial injury and non-cardiac complications in patients undergoing vascular surgery. Additionally, the association between elevated pre-operative high-sensitivity cardiac Troponin T or N-terminal pro-B-type natriuretic peptide and non-cardiac complications was explored.

METHODS

This study is a post hoc analysis of a multicentre randomised controlled trial. Patients were recruited from three centres in Sweden between 2016 and 2019. Cardiac troponin level was measured pre-operatively and at 4, 24, and 48 h after the start of surgery in patients undergoing vascular surgery. N-terminal pro-B-type natriuretic peptide was measured pre-operatively. The primary outcome was a composite of major postoperative non-cardiac complications assessed at 30 days.

RESULTS

A total of 184 patients undergoing peripheral or aortic vascular surgery were included in this study. The primary endpoint occurred in 67 (36%) patients. Perioperative myocardial injury was significantly associated with non-cardiac complications, with an adjusted odds ratio (OR) of 2.71 (95% confidence interval 1.33-5.55, P = 0.01). Sensitivity and specificity were 0.40 and 0.81, respectively. No association was found between pre-operative hs-cTnT or NT-proBNP and non-cardiac complications.

CONCLUSION

In this pilot study, we found that new peri-operative myocardial injury is associated with an increased risk of non-cardiac complications within 30 days after index surgery in patients undergoing vascular surgery. Pre-operative high-sensitivity cardiac Troponin T or N-terminal pro-B-type natriuretic peptide did not appear to predict non-cardiac complications. Larger studies are needed to confirm our findings.

TRIAL REGISTRATION

EudraCT database: 2016-001584-36.

Troponin elevation as a marker of short deterioration and one-year death in a high-risk surgical patient cohort in a low and middle income country setting: a postoperative approach to increase surveillance

PURPOSE

Myocardial injury after noncardiac surgery is common and mostly asymptomatic. The ideal target population that will benefit from routine troponin measurements in low and middle income countries (LMICs) is unclear. This study aims to evaluate the clinical outcomes of a cohort of high-risk surgical patients according to high-sensitivity troponin T (hsTnT) in an LMIC setting.

METHODS

We conducted a prospective cohort study of 442 high-risk patients undergoing noncardiac surgery at a Brazilian hospital between February 2019 and March 2020. High-sensitivity troponin T levels were measured preoperatively, 24 hr, and 48 hr after surgery and stratified into three groups: normal (< 20 ng·L-1); minor elevation (20-65 ng·L-1); and major elevation (> 65 ng·L-1). We performed survival analysis to determine the association between myocardial injury and one-year mortality. We described medical interventions and evaluated unplanned intensive care unit (ICU) admission and complications using multivariable models.

RESULTS

Postoperative myocardial injury occurred in 45% of patients. Overall, 30-day mortality was 8%. Thirty-day and one-year mortality were higher in patients with hsTnT ≥ 20 ng·L-1. One-year mortality was 18% in the unaltered troponin group vs 31% and 41% for minor and major elevation groups, respectively. Multivariable analysis of one-year survival showed a hazard ratio (HR) of 1.94 (95% confidence interval [CI], 1.22 to 3.09) for the minor elevation group and a HR of 2.73 (95% CI, 1.67 to 4.45) for the troponin > 65 ng·L-1 group. Patients with altered troponin had more unplanned ICU admissions (13% vs 5%) and more complications (78% vs 48%).

CONCLUSION

This study supports evidence that hsTnT is an important prognostic marker and a strong predictor of all-cause mortality after surgery. Troponin measurement in high-risk surgical patients could potentially be used as tool to scale-up care in LMIC settings.

STUDY REGISTRATION

ClinicalTrials.gov (NCT04187664); first submitted 5 December 2019.

Incidence and risk factors of postoperative acute myocardial injury in noncardiac patients: A systematic review and meta-analysis

INTRODUCTION

Postoperative myocardial injury after noncardiac surgery is common and is associated with short- and long-term morbidity and mortality. However, the incidence and risk factors for postoperative acute myocardial injury (POAMI) are currently unknown due to inconsistent definitions.

METHODS

We systematically searched PubMed and Web of Science to identify studies that applied the change value of preoperative and postoperative cardiac troponins to define cardiac injury. We estimated the pooled incidence, risk factors, and 30-day and long-term mortality of POAMI in noncardiac patients. The study protocol was registered with PROSPERO, CRD42023401607.

RESULTS

Ten cohorts containing 11,494 patients were included for analysis. The pooled incidence of POAMI was 20% (95% CI: 16% to 23%). Preoperative hypertension (OR: 1.47; 95% CI: 1.30 to 1.66), cardiac failure (OR: 2.63; 95% CI: 2.01 to 3.44), renal impairment (OR: 1.66; 95% CI: 1.48 to 1.86), diabetes (OR: 1.43; 95% CI: 1.27 to 1.61), and preoperative beta-blocker intake (OR: 1.65; 95% CI: 1.10 to 2.49) were the risk factors for POAMI. Age (mean difference: 2.08 years; 95% CI: -0.47 to 4.62), sex (male, OR: 1.16; 95% CI: 0.77 to 1.76), body mass index (mean difference: 0.35; 95% CI: -0.86 to 1.57), preoperative coronary artery disease (OR: 2.10; 95% CI: 0.85 to 5.21), stroke (OR: 0.90; 95% CI: 0.50 to 1.59) and preoperative statins intake (OR: 0.65; 95% CI: 0.21 to 2.02) were not associated with POAMI. Patients with POAMI had higher preoperative hsTnT levels (mean difference: 5.92 ng/L; 95% CI: 4.17 to 7.67) and lower preoperative hemoglobin levels (mean difference: -1.29 g/dL; 95% CI: -1.43 to -1.15) than patients without.

CONCLUSION

Based on this meta-analysis, approximately 1 in 5 of noncardiac patients develop POAMI. However, the lack of a universally recognized definition for POAMI, which incorporates diverse cardiac biomarkers and patient groups, poses a challenge in accurately characterizing its incidence, risk factors, and clinical outcomes.