Single-Molecule High-Sensitivity Troponin I Levels in Stable Patients with Chest Pain

Elevated high-sensitivity troponin I (hsTnI; normal range, <6 ng/L) levels correlate with risk for myocardial infarction (MI) and death in patients with ischemic heart disease. But does hsTnI level predict prognosis in stable patients with chest pain, not all of whom ultimately will receive diagnoses of obstructive coronary disease? In an analysis from PROMISE (NEJM JW Gen Med Apr 15 2015 and N Engl J Med 2015; 372:1291), a randomized trial of functional versus anatomic imaging for detecting coronary artery disease, 4021 stable patients with chest pain had blood drawn for hsTnI analysis. Using a special method that “counts” individual troponin molecules to enhance sensitivity, investigators analyzed whether hsTnI levels predicted adverse ca…