High sensitivity troponin T concentrations in patients undergoing noncardiac surgery: A prospective cohort study☆
Introduction
Noncardiac surgery has made substantial advances in treating diseases and improving patients' quality of life; however, it is also associated with major vascular complications [1]. The Vascular events In noncardiac Surgery patIents cOhort evaluation (i.e., VISION) Study is a large (i.e., 40,000 patient) international prospective cohort study evaluating major vascular complications in a representative sample of patients ≥ 45 years of age undergoing noncardiac surgery. At the beginning of the study, all sites were using the 4th generation troponin T (hence referred to as TnT) assay, but with the 5th generation high sensitivity TnT (hence referred to as hs-TnT) assay gaining regulatory approval there will be a shift to using hs-TnT in this population. The characteristics of the hs-TnT assay in this population are unknown.
Recent publications have reported the analytical characteristics of hs-TnT assay with respect to the 99th percentile (≥ 14 ng/L) in a healthy population, the reference change values (RCVs; > 85%), and the optimal change criteria to identify non-ST segment elevation myocardial infarction (NSTEMI; > 242%) [2], [3], [4]. The PEACE Study demonstrated that 11% of patients with stable coronary artery disease exceeded an hs-TnT assay value ≥ 14 ng/L and that this value was an independent predictor of cardiovascular death [5]. Questions persist, however, regarding whether the reference interval from a healthy population should be applied to all patient populations in all settings [6]. We sought to determine the prevalence of patients exceeding the published 99th percentile versus the derived reference intervals from the preoperative samples from a substudy of VISION patients. We also assessed the different change criteria (85% versus 242%).
Section snippets
Study population
The VISION Bio-bank Study is a substudy of VISION, and includes a prospective sample of VISION patients who are ≥ 45 years of age, undergoing elective or emergent noncardiac surgery requiring overnight hospital admission, and receiving a general or regional anesthetic. Recruitment into the VISION Bio-bank Study has occurred at the following three Canadian hospitals: the Hamilton Health Sciences, Hamilton, Ontario, Saint Joseph's Healthcare, Hamilton, Ontario, and Winnipeg Health Sciences Centre,
Results
The mean (SD) patient age was 65 (11) years, approximately half were female, and there was representation of all major surgical interventions, Table 1. The Revised Cardiac Risk Index suggested that the majority of participants were considered low-risk (i.e., scores of 0 or 1) for a major perioperative vascular complication.
The hs-TnT concentrations were higher postoperatively (days 1, 2, 3) as compared to the preoperative concentrations (Table 1). Preoperatively, 21% (95% CI: 17–25%) of the
Discussion
Our study demonstrates that patients undergoing noncardiac surgery represent a population with significant hs-TnT elevations. Using the published 99th percentile of ≥ 14 ng/L, one in five adults exceeded this threshold prior to surgery. This positive rate increased postoperatively with over 40% of subjects having a postoperative hs-TnT concentration ≥ 14 ng/L. Some authors advocate the need for a change in concentration beyond surpassing a hs-TnT threshold. When both of these criteria are employed
Acknowledgments
Funding and support for this study was obtained via grants from the CANadian Network and Centre for Trials Internationally (CANNeCTIN), Canadian Institutes of Health Research, the Heart and Stroke Foundation of Ontario, Diagnostic Services of Manitoba, and Roche Diagnostics
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Cited by (0)
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Sources of support: grants from the CANadian Network and Centre for Trials Internationally (CANNeCTIN), Canadian Institutes of Health Research, the Heart and Stroke Foundation of Ontario, Diagnostic Services of Manitoba, and Roche Diagnostics.