Bonaca Marc P, O'Malley Ryan G, Murphy Sabina A, Jarolim Petr, Conrad Michael J, Braunwald Eugene, Sabatine Marc S, Morrow David A
Department of Medicine, Brigham and Women's Hospital, Boston, USA
Department of Medicine, Brigham and Women's Hospital, Boston, USA.
Eur Heart J Acute Cardiovasc Care. 2015 Oct;4(5):431-40. doi: 10.1177/2048872614564081. Epub 2014 Dec 23.
Newer troponin assays offer the ability to quantify circulating troponin levels at an order of magnitude lower than contemporary assays, fueling continued debate over the prognostic implications of very low-level increases in concentration. We evaluated the prognostic implications of low-level increases in cardiac troponin I (cTnI) using an investigational single-molecule high-sensitivity assay in patients with acute coronary syndrome (ACS).
We measured cTnI using both a high-sensitivity troponin I (hsTnI) assay (Erenna, Singulex, 99(th) percentile 9 pg/ml) and a current generation sensitive assay (TnI-Ultra, Siemens, 99(th) percentile 40 pg/ml) at baseline in 1807 patients with non-ST elevation ACS and compared their prognostic ability for adverse cardiovascular events at 30 days and one year.
Among patients with TnI-Ultra<99(th) percentile, patients with elevated hsTnI (≥ 9 pg/ml) had a significantly higher risk than patients with hsTnI<9 pg/ml: cardiovascular death (CVD) or myocardial infarction (MI) at one year (7.0% vs 3.8%; p<0.001, hazard ratio (HR) 2.05, confidence interval (CI) 1.23-3.41); including a higher risk of CVD (3.5% vs 1.5%, p<0.001) and MI (5.0% vs 2.8%, p<0.001) individually. This higher risk of CVD/MI was independent of clinical risk stratification using the TIMI Risk Score (adj. HR 1.76, CI 1.05-2.90). Moreover, hsTnI showed a trend toward a gradient of risk even below the hsTnI 99 percentile.
Low-level cardiac troponin detected using a single-molecule technique, below the cutpoint of a contemporary sensitive assay, identified a significant gradient of risk. These findings support the prognostic relevance of low-level cardiac troponin elevation with increasingly sensitive assays in patients with ACS.
新型肌钙蛋白检测方法能够以比当代检测方法低一个数量级的水平对循环肌钙蛋白水平进行定量，这引发了关于浓度极低水平升高的预后意义的持续争论。我们使用一种研究性单分子高灵敏度检测方法评估了急性冠状动脉综合征（ACS）患者中心肌肌钙蛋白I（cTnI）低水平升高的预后意义。
我们在1807例非ST段抬高型ACS患者基线时，使用高灵敏度肌钙蛋白I（hsTnI）检测方法（Erenna，Singulex，第99百分位数为9 pg/ml）和当代灵敏检测方法（TnI-Ultra，西门子，第99百分位数为40 pg/ml）测量cTnI，并比较它们对30天和1年时不良心血管事件的预后能力。
在TnI-Ultra<第99百分位数的患者中，hsTnI升高（≥9 pg/ml）的患者比hsTnI<9 pg/ml的患者风险显著更高：1年时心血管死亡（CVD）或心肌梗死（MI）（7.0%对3.8%；p<0.001，风险比（HR）2.05，置信区间（CI）1.23 - 3.41）；单独来看，CVD风险更高（3.5%对1.5%，p<0.001）和MI风险更高（5.0%对2.8%，p<0.001）。这种更高的CVD/MI风险独立于使用TIMI风险评分的临床风险分层（校正HR 1.76，CI 1.05 - 2.90）。此外，即使在hsTnI第99百分位数以下，hsTnI也显示出风险梯度趋势。
使用单分子技术检测到的低于当代灵敏检测方法切点的低水平心肌肌钙蛋白，识别出了显著的风险梯度。这些发现支持了在ACS患者中，随着检测方法越来越灵敏，低水平心肌肌钙蛋白升高的预后相关性。
