What is the management approach for patients with elevated high sensitivity troponin (hs-troponin) levels?

From the Guidelines

Management of patients with elevated high sensitivity troponin (hs-troponin) requires a systematic approach based on clinical presentation and troponin trends, with an emphasis on risk stratification using clinical features, ECG findings, and serial troponin measurements, as recommended by the 2015 ESC guidelines 1.

Key Considerations

• For patients with suspected acute coronary syndrome (ACS), immediate treatment includes aspirin, antiplatelet therapy, and anticoagulation, with additional medications such as beta-blockers, statins, and nitroglycerin for symptomatic relief.
• Serial troponin measurements should be obtained at 0,3, and 6 hours to assess for dynamic changes, with a significant rise or fall (typically >20% if elevated baseline) suggesting acute myocardial injury, as noted in the 2014 AHA/ACC guideline 1.
• Patients with confirmed NSTEMI should undergo coronary angiography within 24-72 hours based on risk factors, while STEMI requires immediate reperfusion therapy.
• Not all troponin elevations indicate ACS; other causes include heart failure, pulmonary embolism, myocarditis, sepsis, and renal failure, which require targeted management of the underlying condition, as outlined in the universal definition of myocardial infarction 1.

Interpretation of Troponin Elevations

• A troponin value above the 99th percentile of the upper reference level is required for the diagnosis of acute myocardial necrosis, with evidence for a serial increase or decrease ≥20% if the initial value is elevated, as recommended by the 2014 AHA/ACC guideline 1.
• Absolute changes in nanograms per liter of high-sensitivity cardiac troponin T levels appear to have a significantly higher diagnostic accuracy for AMI than relative changes, as noted in the 2014 AHA/ACC guideline 1.
• Troponin elevations can be due to various causes, including tachyarrhythmia, hypotension or hypertension, cardiac trauma, acute heart failure, myocarditis, and pericarditis, as well as severe noncardiac conditions such as sepsis, burns, respiratory failure, acute neurological diseases, and drug toxicity, as outlined in the universal definition of myocardial infarction 1.

Clinical Context

• Chronic elevations may be seen in elderly patients or those with chronic kidney disease and should be interpreted in clinical context rather than automatically triggering ACS protocols, as recommended by the 2015 ESC guidelines 1.
• The use of high-sensitivity cardiac troponin assays is recommended over less sensitive ones, with automated assays having been more thoroughly evaluated as compared with point-of-care tests, as noted in the 2015 ESC guidelines 1.

From the Research

Interpretation of High Sensitivity Troponin

• High sensitivity troponin (hs-troponin) is a biomarker used to diagnose myocardial infarction and acute coronary syndrome 2.
• Elevated hs-troponin levels indicate cardiac muscle cell damage, which can be caused by various conditions, including myocardial infarction, myocarditis, trauma, unstable angina, cardiac surgery, or other cardiac procedures 2.
• The presence of hs-troponin in the circulation at levels above normal is good evidence of cardiac injury 2.

Management Approach for Patients with Elevated hs-Troponin Levels

• The diagnosis of acute coronary syndrome remains a clinical-based diagnosis, and the use of troponin levels contributes to its classification 2.
• Patients with elevated hs-troponin levels should be evaluated for underlying conditions that may be causing the elevation, such as myocardial infarction, type 2 myocardial infarction, or other cardiac injuries 3.
• The interpretation of hs-troponin assay results can be challenging, especially in patients with multiple comorbidities and organ failures 3.
• High-sensitivity cardiac troponins are powerful predictors of long-term mortality and cardiovascular disease in the general population and in patients with chest pain with or without cardiovascular disease 4.

Clinical Implications of Elevated hs-Troponin Levels

• Elevated hs-troponin levels are associated with an increased risk of death and cardiovascular disease, even at levels below the upper normal limit 4.
• The magnitude and change in troponin concentration can help differentiate causes of myocardial injury and infarction, but troponin concentrations at presentation are insufficient to distinguish type 1 myocardial infarction from other causes of myocardial injury or infarction 5.
• The 99th percentile and rule-in thresholds of hs-troponin can provide a positive predictive value and specificity for diagnosing type 1 myocardial infarction, but should not guide management decisions in isolation 5.
• Predictors of elevated hs-troponin levels include sex, age, and estimated glomerular filtration rate (eGFR), with reduced eGFR being the strongest predictor 6.