Use of High-Sensitivity Cardiac Troponin for the Exclusion of Inducible Myocardial Ischemia: A Cohort Study

• Published in: Annals of internal medicine Vol. 169; no. 11; p. 751
• Main Authors: Hammadah, Muhammad, Kim, Jeong Hwan, Tahhan, Ayman Samman, Kindya, Bryan, Liu, Chang, Ko, Yi-An, Al Mheid, Ibhar, Wilmot, Kobina, Ramadan, Ronnie, Alkhoder, Ayman, Choudhary, Fahad, Gafeer, Mohamad Mazen, Abdelhadi, Naser, Pimple, Pratik, Sandesara, Pratik, Lima, Bruno B, Shah, Amit J, Ward, Laura, Kutner, Michael, Bremner, J Douglas, Sheps, David S, Raggi, Paolo, Sperling, Laurence S, Vaccarino, Viola, Quyyumi, Arshed A
• Format: Journal Article
• Language: English
• Published: United States 04.12.2018
• Subjects: Aged; Biomarkers - blood; Exercise Test; Female; Follow-Up Studies; Humans; Male; Middle Aged; Myocardial Ischemia - diagnosis; Myocardial Ischemia - diagnostic imaging; Myocardial Perfusion Imaging; Predictive Value of Tests; Radiopharmaceuticals; Technetium; Tomography, Emission-Computed, Single-Photon; Troponin I - blood
• ISSN: 1539-3704
• DOI: 10.7326/M18-0670

Many patients with coronary artery disease (CAD) are routinely referred for surveillance stress testing despite recommendations against it. To determine whether low levels of resting high-sensitivity cardiac troponin I (hs-cTnI) can identify persons without inducible myocardial ischemia. Observational study. A university-affiliated hospital network. Persons with stable CAD: 589 in the derivation group and 118 in the validation cohort. Presence of inducible myocardial ischemia was determined by myocardial perfusion imaging with technetium-99m single-photon emission computed tomography during either treadmill or pharmacologic stress testing. Resting plasma hs-cTnI was measured within 1 week of the stress test, and the negative predictive value (NPV) for inducible ischemia was calculated. The derivation cohort was followed for 3 years for incident cardiovascular death and myocardial infarction. In the derivation cohort, 10 of 101 patients with an hs-cTnI level below 2.5 pg/mL had inducible myocardial ischemia (NPV, 90% [95% CI, 83% to 95%]) and 3 of 101 had inducible ischemia involving at least 10% of the myocardium (NPV, 97% [CI, 92% to 99%]). In the validation cohort, 4 of 32 patients with an hs-cTnI level below 2.5 pg/mL had inducible ischemia (NPV, 88% [CI, 71% to 96%]) and 2 of 32 had ischemia of 10% or greater (NPV, 94% [CI, 79% to 99%]). After a median follow-up of 3 years in the derivation cohort, no adverse events occurred in patients with an hs-cTnI level below 2.5 pg/mL, compared with 33 (7%) cardiovascular deaths or incident myocardial infarctions among those with an hs-cTnI level of 2.5 pg/mL or greater. The data may not be applicable to a population without known CAD or to persons with unstable angina, and the modest sample sizes warrant further validation in a larger cohort. Very low hs-cTnI levels may be useful in excluding inducible myocardial ischemia in patients with stable CAD. National Institutes of Health.