Association Between High-Sensitivity Cardiac Troponin Levels and Myocardial Ischemia During Mental Stress and Conventional Stress

作者：Hammadah Muhammad; Al Mheid Ibhar; Wilmot Kobina; Ramadan Ronnie; Alkhoder Ayman; Obideen Malik; Abdelhadi Naser; Fang Shuyang; Ibeanu Ijeoma; Pimple Pratik; Kelli Heval Mohamed; Shah Amit J; Pearce Brad; Sun Yan; Garcia Ernest V; Kutner Michael; Long Qi; Ward Laura; Bremner J Douglas; Esteves Fabio; Raggi Paolo; Sheps David; Vaccarino Viola; Quyyumi Arshed A^*

来源：JACC: Cardiovascular Imaging , 2018, 11(4): 603-611.

DOI：10.1016/j.jcmg.2016.11.021

• high-sensitivity troponin I
• mental stress
• myocardial ischemia
• physical stress

OBJECTIVES This study sought to investigate whether patients with mental stress-induced myocardial ischemia will have high resting and post-mental stress high-sensitivity cardiac troponin I (hs-cTnI).
BACKGROUND Hs-cTnI is a marker of myocardial necrosis, and its elevated levels are associated with adverse outcomes. Hs-cTnI levels may increase with exercise in patients with coronary artery disease. Mental stress-induced myocardial ischemia is also linked to adverse outcomes.
METHODS In this study, 587 patients with stable coronary artery disease underwent technetium Tc 99m sestamibi-single-photon emission tomography myocardial perfusion imaging during mental stress testing using a public speaking task and during conventional (pharmacological/exercise) stress testing as a control condition. Ischemia was defined as new/worsening impairment in myocardial perfusion using a 17-segment model.
RESULTS The median hs-cTnI resting level was 4.3 (interquartile range [IQR]: 2.9 to 7.3) pg/ml. Overall, 16% and 34.8% of patients developed myocardial ischemia during mental and conventional stress, respectively. Compared with those without ischemia, median resting hs-cTnI levels were higher in patients who developed ischemia either during mental stress (5.9 [IQR: 3.9 to 8.3] pg/ml vs. 4.1 [IQR: 2.7 to 7.0] pg/ml; p < 0.001) or during conventional stress (5.4 [IQR: 3.9 to 9.3] pg/ml vs. 3.9 [IQR: 2.5 to 6.5] pg/ml; p < 0.001). Patients with high hs-cTnI (cutoff of 4.6 pg/ml for men and 3.9 pg/ml for women) had greater odds of developing mental (odds ratio [OR]: 2.4; 95% confidence interval [CI]: 1.5 to 3.9; p < 0.001) and conventional (OR: 2.4; 95% CI: 1.7 to 3.4; p < 0.001) stress-induced ischemia. Although there was a significant increase in 45-min post-treadmill exercise hs-cTnI levels in those who developed ischemia, there was no significant increase after mental or pharmacological stress test.
CONCLUSIONS In patients with coronary artery disease, myocardial ischemia during either mental stress or conventional stress is associated with higher resting levels of hs-cTnI. This suggests that hs-cTnI elevation is an indicator of chronic ischemic burden experienced during everyday life. Whether elevated hs-cTnI levels are an indicator of adverse prognosis beyond inducible ischemia or whether it is amenable to intervention requires further investigation.

• 出版日期2018-4