Hijazi Ziad, Lindahl Bertil, Oldgren Jonas, Andersson Ulrika, Lindbäck Johan, Granger Christopher B, Alexander John H, Gersh Bernard J, Hanna Michael, Harjola Veli-Pekka, Hylek Elaine M, Lopes Renato D, Siegbahn Agneta, Wallentin Lars
Uppsala Clinical Research Center, Uppsala University, Uppsala, Sweden
Department of Medical Sciences, Cardiology, Uppsala University, Uppsala Sweden.
J Am Heart Assoc. 2017 Jun 23;6(6):e004851. doi: 10.1161/JAHA.116.004851.
Cardiac biomarkers are independent risk markers in atrial fibrillation, and the novel biomarker-based ABC stroke score (age, biomarkers, and clinical history of prior stroke) was recently shown to improve the prediction of stroke risk in patients with atrial fibrillation. Our aim was to investigate the short-term variability of the cardiac biomarkers and evaluate whether the ABC stroke risk score provides a stable short-term risk estimate.
According to the study protocol, samples were obtained at entry and also at 2 months in 4796 patients with atrial fibrillation followed for a median of 1.8 years in the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial. Cardiac troponin I, cardiac troponin T, and N-terminal pro-B-type natriuretic peptide were measured with high-sensitivity immunoassays. Associations with outcomes were evaluated by Cox regression. C indices and calibration plots were used to evaluate the ABC stroke score at 2 months. The average changes in biomarker levels during 2 months were small (median change cardiac troponin T +2.8%, troponin I +2.0%, and N-terminal pro-B-type natriuretic peptide +13.5%) and within-subject correlation was high (all ≥0.82). Repeated measurement of cardiac biomarkers provided some incremental prognostic value for mortality but not for stroke when combined with clinical risk factors and baseline levels of the biomarkers. Based on 8702 person-years of follow-up and 96 stroke/systemic embolic events, the ABC stroke score at 2 months achieved a similar C index of 0.70 (95% CI, 0.65-0.76) as compared with 0.70 (95% CI, 0.65-0.75) at baseline. The ABC stroke score remained well calibrated using predefined risk classes.
In patients with stable atrial fibrillation, the variability of the cardiac biomarkers and the biomarker-based ABC stroke score during 2 months are small. The prognostic information by the ABC stroke score remains consistent and well calibrated with similar good predictive performance if patients are retested after 2 months.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984.
心脏生物标志物是心房颤动的独立风险标志物，最近一项基于新型生物标志物的ABC卒中评分（年龄、生物标志物和既往卒中临床病史）显示可改善心房颤动患者卒中风险的预测。我们的目的是研究心脏生物标志物的短期变异性，并评估ABC卒中风险评分是否能提供稳定的短期风险估计。
根据研究方案，在ARISTOTLE（阿哌沙班用于降低心房颤动患者卒中及其他血栓栓塞事件）试验中，对4796例心房颤动患者在入组时和2个月时采集样本，这些患者的中位随访时间为1.8年。采用高灵敏度免疫测定法检测心肌肌钙蛋白I、心肌肌钙蛋白T和N末端B型利钠肽原。通过Cox回归评估与结局的关联。使用C指数和校准图评估2个月时的ABC卒中评分。2个月内心脏生物标志物水平的平均变化较小（心肌肌钙蛋白T中位变化+2.8%，肌钙蛋白I +2.0%，N末端B型利钠肽原+13.5%），且受试者内相关性较高（均≥0.82）。与临床风险因素和生物标志物基线水平相结合时，重复测量心脏生物标志物对死亡率有一定的增量预后价值，但对卒中无此价值。基于8702人年的随访和96例卒中/全身性栓塞事件，2个月时的ABC卒中评分的C指数为0.70（95%CI，0.65 - 0.76），与基线时的0.70（95%CI，0.65 - 0.75）相似。使用预定义的风险类别时，ABC卒中评分校准良好。
在稳定型心房颤动患者中，2个月内心脏生物标志物及基于生物标志物的ABC卒中评分的变异性较小。如果患者在2个月后重新检测，ABC卒中评分的预后信息保持一致且校准良好，具有相似的良好预测性能。
