A novel breakthrough in wrist-worn transdermal troponin-I-sensor assessment for acute myocardial infarction

Clinical question: Can a novel wrist-worn transdermal infrared spectrophotometric sensor (transdermal-ISS) that can detect elevated troponin levels within 5 minutes without a blood draw be used in a clinical setting to evaluate for acute coronary syndrome (ACS)?

What was already known: Although measurement of serial cardiac troponin levels is recommended for patients presenting with ACS within a turnaround time of 60 minutes, turnover times for troponin testing are variable due to strained hospital resources and patients may benefit from a more efficient testing method.

Methods: This was a head-to-head comparison of high-sensitivity troponin (HST) levels by blood draw and transdermal-ISS recordings at a single random time point during admission. The sample consisted of 238 patients admitted for ACS at 5 hospitals in India.

Results/implications: Transdermal-ISS recordings, alongside a machine learning model developed by the authors, showed high accuracy and stability for detecting elevated troponin levels (ROC: 0.90, sensitivity: 0.86, specificity: 0.82 in internal validation; ROC: 0.92, sensitivity: 0.94, specificity: 0.64 in external validation). Abnormal transdermal-ISS findings were found to be associated with obstructive CAD, even after adjusting for sex and smoking history.

Bottom line: In patients hospitalized with ACS, transdermal-ISS recordings of troponin by a wrist-worn device demonstrated high accuracy and stability for detecting elevated troponin compared to traditional serum high-sensitivity troponin testing, suggesting that wrist-worn devices may have a clinical role in non-invasive detection of ACS.