Does the serum cardiac troponin I level increase with stress test-induced myocardial ischemia?

To evaluate the sensitivity of the serum cardiac troponin I level in detecting stress test-induced myocardial ischemia, the authors conducted a prospective study including patients admitted for chest pain to the telemetry floor of Our Lady of Mercy Medical Center at Bronx, NY. Consecutive 134 telemetry patients that agreed to participate in this study were included. All of these patients had a nuclear stress test and were divided into various groups based on the prestress test probability of having coronary artery disease. To assess serum cardiac troponin I levels, blood samples were drawn before and after stress testing and compared with the stress test results. Overall, 30 patients (22%) had reversible perfusion defects on stress images, and none (0%) had increased serum cardiac troponin I levels. One patient of 18 patients (6%) in group C with negative stress test results had an elevated serum cardiac troponin I level after the stress test, but none of group A or group B patients had elevated troponin I levels. These data show that serum cardiac troponin I levels do not increase with stress test-induced myocardial ischemia.