Association of High-Sensitivity Cardiac Troponin I Concentration With Cardiac Outcomes in Patients With Suspected
Andrew R Chapman1, Kuan Ken Lee1, David A McAllister2
1BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, Scotland.
Insights
A high-sensitivity cardiac troponin I level below 5 ng/L effectively identifies low-risk patients with suspected acute coronary syndrome. This threshold demonstrates a high negative predictive value for myocardial infarction or cardiac death within 30 days.
Area of Science:
- Cardiology
- Biomarkers
- Diagnostic Accuracy
Background:
- High-sensitivity cardiac troponin I (hs-cTnI) is crucial for diagnosing acute coronary syndrome (ACS).
- A hs-cTnI concentration <5 ng/L is often used to identify low-risk patients, but its optimal threshold for risk stratification remains uncertain.
Purpose of the Study:
- To evaluate the performance of a hs-cTnI threshold of 5 ng/L for risk stratification in patients with suspected ACS.
- To determine the accuracy of this threshold in predicting myocardial infarction or cardiac death.
Main Methods:
- Systematic literature search of major databases (MEDLINE, EMBASE, Cochrane, Web of Science) from 2006 to 2017.
- Meta-analysis of 19 prospective cohorts including 22,457 patients, with individual patient-level data from 17 cohorts.
- Evaluation of hs-cTnI concentrations across a range of 2-16 ng/L to assess risk stratification performance.
Main Results:
- A hs-cTnI concentration <5 ng/L was observed in 49% of patients (11,012/22,457).
- This low hs-cTnI group had a 99.5% negative predictive value (95% CI, 99.3%-99.6%) for the primary outcome (myocardial infarction or cardiac death within 30 days).
- No cardiac deaths occurred within 30 days in this low-risk group, with a 99.9% negative predictive value for cardiac death at 1 year.
Conclusions:
- A hs-cTnI concentration <5 ng/L reliably identifies patients with suspected ACS who are at low risk of 30-day myocardial infarction or cardiac death.
- Further research is recommended to explore the clinical utility and cost-effectiveness of this risk stratification strategy.
- The findings support the use of a 5 ng/L hs-cTnI threshold for ruling out ACS in select patient populations.
Importance:
High-sensitivity cardiac troponin I testing is widely used to evaluate patients with suspected acute coronary syndrome. A cardiac troponin concentration of less than 5 ng/L identifies patients at presentation as low risk, but the optimal threshold is uncertain.
Objective:
To evaluate the performance of a cardiac troponin I threshold of 5 ng/L at presentation as a risk stratification tool in patients with suspected acute coronary syndrome.
Data Sources:
Systematic search of MEDLINE, EMBASE, Cochrane, and Web of Science databases from January 1, 2006, to March 18, 2017.
Study Selection:
Prospective studies measuring high-sensitivity cardiac troponin I concentrations in patients with suspected acute coronary syndrome in which the diagnosis was adjudicated according to the universal definition of myocardial infarction.
Data Extraction And Synthesis:
The systematic review identified 19 cohorts. Individual patient-level data were obtained from the corresponding authors of 17 cohorts, with aggregate data from 2 cohorts. Meta-estimates for primary and secondary outcomes were derived using a binomial-normal random-effects model.
Main Outcomes And Measures:
The primary outcome was myocardial infarction or cardiac death at 30 days. Performance was evaluated in subgroups and across a range of troponin concentrations (2-16 ng/L) using individual patient data.
Results:
Of 11 845 articles identified, 104 underwent full-text review, and 19 cohorts from 9 countries were included. Among 22 457 patients included in the meta-analysis (mean age, 62 [SD, 15.5] years; n = 9329 women [41.5%]), the primary outcome occurred in 2786 (12.4%). Cardiac troponin I concentrations were less than 5 ng/L at presentation in 11 012 patients (49%), in whom there were 60 missed index or 30-day events (59 index myocardial infarctions, 1 myocardial infarction at 30 days, and no cardiac deaths at 30 days). This resulted in a negative predictive value of 99.5% (95% CI, 99.3%-99.6%) for the primary outcome. There were no cardiac deaths at 30 days and 7 (0.1%) at 1 year, with a negative predictive value of 99.9% (95% CI, 99.7%-99.9%) for cardiac death.
Conclusions And Relevance:
Among patients with suspected acute coronary syndrome, a high-sensitivity cardiac troponin I concentration of less than 5 ng/L identified those at low risk of myocardial infarction or cardiac death within 30 days. Further research is needed to understand the clinical utility and cost-effectiveness of this approach to risk stratification.
More Related Videos
07:40Impact of High-intensity Interval Exercise and Moderate-Intensity Continuous Exercise on the Cardiac Troponin T Level at an Early Stage of Training
Published on: October 10, 2019
09:23Using Extraordinary Optical Transmission to Quantify Cardiac Biomarkers in Human Serum
Published on: December 13, 2017
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:30Acute Coronary Syndrome I: Introduction
01:20Blood Studies for Cardiovascular System I: Cardiac Biomarkers
The essential diagnostic tools for detecting myocardial necrosis and monitoring individuals suspected of having acute coronary syndrome (ACS) include:
Troponins
Troponins, particularly cardiac troponins I and T, are the most precise and sensitive markers of myocardial injury. They are detectable within 4-6 hours of myocardial injury and remain...
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:19Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers
These markers indicate stress or strain on the heart muscle:
Natriuretic Peptides (BNP)
Cardiac myocytes produce these hormones in response to ventricular stretching...
01:28Acute Coronary Syndrome IV: Interprofessional Care