Pham Michael X, Whooley Mary A, Evans G Thomas, Liu Catherine, Emadi Homeira, Tong Winnie, Murphy M Catherine, Fleischmann Kirsten E
General Internal Medicine Section, Veterans Affairs Medical Center, and the Division of General Internal Medicine, Department of Medicine, University of California San Francisco, San Francisco, Calif, USA.
Am Heart J. 2004 Nov;148(5):776-82. doi: 10.1016/j.ahj.2004.03.058.
Low-level cardiac troponin-I (cTn-I) elevations predict adverse cardiovascular outcomes in patients with definite acute coronary syndromes (ACS), as defined by the presence of chest pain accompanied by ischemic electrocardiographic changes. However, their prognostic value in other clinical situations remains unclear.
We studied 366 patients with suspected myocardial infarction (MI) but without definite ACS, including 57 patients with low-level cTn-I elevations (1.0 to 3.0 ng/mL) and 309 patients with cTn-I <1.0 ng/mL. All cTn-I measurements were made with the Dade Stratus II analyzer. We determined the adjusted 1-year risk of nonfatal MI or death from coronary heart disease (CHD death) in each group by using Cox proportional hazards models.
Among patients with cTn-I elevations between 1.0 and 3.0 ng/mL, 6 (11%) had a nonfatal MI or CHD death at 1 year compared with 12 (4%) patients in the cTn-I <1.0 ng/mL group [hazard ratio (HR), 3.5; 95% CI, 1.4 to 8.8]. After adjusting for baseline clinical characteristics, cTn-I levels between 1.0 and 3.0 ng/mL remained strongly associated with nonfatal MI or CHD death (adjusted HR, 3.4; 95% CI, 1.3 to 9.4). This association persisted even in the 215 patients who presented without chest pain (adjusted HR, 4.3; 95% CI, 1.4 to 13).
Low-level cTn-I elevations identify a subset of patients at increased risk for future cardiovascular events, even when obtained outside the context of definite ACS or presentation with chest pain.
低水平心肌肌钙蛋白I（cTn-I）升高可预测确诊急性冠脉综合征（ACS）患者的不良心血管结局，ACS定义为伴有缺血性心电图改变的胸痛。然而，其在其他临床情况下的预后价值仍不明确。
我们研究了366例疑似心肌梗死（MI）但未确诊ACS的患者，包括57例cTn-I水平低水平升高（1.0至3.0 ng/mL）的患者和309例cTn-I<1.0 ng/mL的患者。所有cTn-I测量均使用Dade Stratus II分析仪进行。我们使用Cox比例风险模型确定每组非致死性MI或冠心病死亡（CHD死亡）的校正1年风险。
在cTn-I水平在1.0至3.0 ng/mL之间的患者中，1年时有6例（11%）发生非致死性MI或CHD死亡，而cTn-I<1.0 ng/mL组有12例（4%）患者发生此类情况[风险比（HR），3.5；95%CI，1.4至8.8]。在调整基线临床特征后，cTn-I水平在1.0至3.0 ng/mL之间仍与非致死性MI或CHD死亡密切相关（校正HR，3.4；95%CI，1.3至9.4）。即使在215例无胸痛表现的患者中，这种关联仍然存在（校正HR，4.3；95%CI，1.4至13）。
低水平cTn-I升高可识别出未来心血管事件风险增加的一部分患者，即使是在确诊ACS或有胸痛表现之外的情况下测得。
