Division of Medicine, Akershus University Hospital, Lørenskog, Norway.
N Engl J Med. 2009 Dec 24;361(26):2538-47. doi: 10.1056/NEJMoa0805299. Epub 2009 Nov 25.
In most patients with stable coronary artery disease, plasma cardiac troponin T levels are below the limit of detection for the conventional assay. The distribution and determinants of very low circulating troponin T levels, as well as their association with cardiovascular events, in such patients are unknown.
We used a new, high-sensitivity assay to determine the concentration of cardiac troponin T in plasma samples from 3679 patients with stable coronary artery disease and preserved left ventricular function. Results of the assay were analyzed in relation to the incidence of cardiovascular events during a median follow-up period of 5.2 years.
With the highly sensitive assay, concentrations of cardiac troponin T were at or above the limit of detection (0.001 microg per liter) in 3593 patients (97.7%) and at or above the 99th percentile for apparently healthy subjects (0.0133 microg per liter) in 407 patients (11.1%). After adjustment for other independent prognostic indicators, there was a strong and graded increase in the cumulative incidence of cardiovascular death (adjusted hazard ratio per unit increase in the natural logarithm of the troponin T level, 2.09; 95% confidence interval [CI], 1.60 to 2.74; P<0.001) and of heart failure (adjusted hazard ratio, 2.20; 95% CI, 1.66 to 2.90; P<0.001) in this study group. Increased risk associated with higher levels of troponin T was evident well below the limit of detection of conventional cardiac troponin T assays and below the 99th percentile of values in a healthy population. There was no association between troponin T levels as measured with the highly sensitive assay and the incidence of myocardial infarction (adjusted hazard ratio, 1.16; 95% CI, 0.97 to 1.40; P=0.11).
After adjustment for other independent prognostic indicators, cardiac troponin T concentrations as measured with a highly sensitive assay were significantly associated with the incidence of cardiovascular death and heart failure but not with myocardial infarction in patients with stable coronary artery disease.
在大多数稳定性冠心病患者中，常规检测方法检测不到血浆心肌肌钙蛋白 T 水平。在这些患者中，极低循环心肌肌钙蛋白 T 水平的分布和决定因素，以及它们与心血管事件的关系尚不清楚。
我们使用一种新的高敏检测方法，测定了 3679 例稳定性冠心病和左心室功能正常的患者的血浆心肌肌钙蛋白 T 浓度。在中位随访 5.2 年期间，分析检测结果与心血管事件发生率的关系。
使用高敏检测方法，3593 例患者（97.7%）的心肌肌钙蛋白 T 浓度达到或超过检测限（0.001μg/L），407 例患者（11.1%）的浓度达到或超过健康人群第 99 百分位值（0.0133μg/L）。在校正其他独立预后指标后，心血管死亡（每单位自然对数值肌钙蛋白 T 水平的校正危险比，2.09；95%置信区间[CI]，1.60 至 2.74；P<0.001）和心力衰竭（校正危险比，2.20；95%CI，1.66 至 2.90；P<0.001）的累积发生率呈强烈的分级增加。在该研究组中，与较高的肌钙蛋白 T 水平相关的风险明显低于常规心肌肌钙蛋白 T 检测的检测限，也低于健康人群的第 99 百分位值。高敏检测方法测定的肌钙蛋白 T 水平与心肌梗死发生率之间无相关性（校正危险比，1.16；95%CI，0.97 至 1.40；P=0.11）。
在校正其他独立预后指标后，高敏检测方法测定的心肌肌钙蛋白 T 浓度与稳定性冠心病患者心血管死亡和心力衰竭的发生率显著相关，但与心肌梗死无关。
