Acute Kidney Injury and High-Sensitivity Cardiac Troponin T Levels in the Emergency Department

Area of Science:

• Cardiology
• Nephrology
• Emergency Medicine

Background:

• High-sensitivity cardiac troponin T (hs-cTnT) is a biomarker for myocardial injury.
• Acute kidney injury (AKI) is common in emergency department (ED) patients and can affect hs-cTnT levels.
• The clinical implications of hs-cTnT in AKI patients within the ED are not well understood.

Purpose of the Study:

• To examine the relationship between serum creatinine (SCr) concentrations and hs-cTnT kinetics in AKI patients.
• To evaluate the accuracy of hs-cTnT for diagnosing myocardial infarction (MI) in patients with AKI.

Main Methods:

• Retrospective cohort study of 15,211 ED visits from 7 Swedish hospitals (2010-2017).
• Included patients aged 18+ with AKI criteria, multiple SCr, and hs-cTnT measurements.
• Used linear mixed-effects and logistic regression models to analyze hs-cTnT changes and MI diagnostic performance.

Main Results:

• Increased SCr changes were associated with higher hs-cTnT levels, suggesting myocardial injury in 81% of non-MI patients.
• Patients with the highest SCr change quartile had a 1.8-fold higher hs-cTnT change and were twice as likely to have acute myocardial injury.
• hs-cTnT algorithms showed low specificity and positive predictive value for MI in patients with chest pain.

Conclusions:

• Dynamic SCr changes in AKI patients are linked to hs-cTnT elevations indicative of myocardial injury.
• Current hs-cTnT-based MI risk stratification algorithms perform poorly in AKI patients.
• Further research is needed to refine cardiac biomarker interpretation in AKI.