肌红蛋白预测因排除心肌梗死而入院患者死亡率的能力。

Ability of myoglobin to predict mortality in patients admitted for exclusion of myocardial infarction.

作者信息

Kontos Michael C, Garg Rajat, Anderson F Philip, Roberts Charlotte S, Ornato Joseph P, Tatum James L, Jesse Robert L

机构信息

Cardiology Division, Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA 23298-0051, USA.

出版信息

Am J Emerg Med. 2007 Oct;25(8):873-9. doi: 10.1016/j.ajem.2007.01.002.

DOI:10.1016/j.ajem.2007.01.002

PMID:17920970

Abstract

BACKGROUND

Myoglobin can be used as an early marker to diagnose myocardial infarction (MI); and although nonspecific for myocardial necrosis, it seems to be a strong mortality predictor. Because myoglobin elevations are often present in patients with renal insufficiency, it is possible that the predictive value of myoglobin is secondary to identifying patients with renal insufficiency.

METHODS

Consecutive patients admitted for MI exclusion without ST elevation on the initial electrocardiogram underwent serial assessment of cardiac markers (creatine kinase [CK], CK-myocardial band [MB], and troponin I [TnI]). Myoglobin was assessed at the time of admission and/or 3 hours later. Renal insufficiency was defined as a creatinine clearance <60 mL/min. Multivariate analysis was performed to identify predictors of 30-day and 1-year all-cause mortality.

RESULTS

A total of 3461 patients were included in the analysis. Overall 30-day and 1-year mortality was 2.4% and 9.7%. Myoglobin was elevated in 675 (20%), CK-MB in 421 (12%), and TnI in 517 (15%). Among the 993 patients with renal insufficiency, myoglobin was elevated in 43%, CK-MB in 17%, and TnI in 21%. Independent predictors of 30-day and 1-year mortality were similar and included age > or =65 years, prior MI, and an ischemic electrocardiogram, whereas myoglobin was the strongest multivariate predictor (odds ratio [OR] 2.8, 95% confidence interval [CI] 2.1-3.7), including those with renal insufficiency (OR 2.3, 95% CI 1.6-3.4). Troponin I had borderline predictive value (P = .08, OR 1.4, 95% CI 0.96-2.0), whereas CK-MB was not predictive in either group.

CONCLUSIONS

Despite the absence of cardiac specificity, an elevated myoglobin strongly predicts mortality, even in patients with renal insufficiency.

摘要

背景

肌红蛋白可作为诊断心肌梗死（MI）的早期标志物；尽管它对心肌坏死不具有特异性，但似乎是一个强有力的死亡预测指标。由于肾功能不全患者中肌红蛋白水平常升高，因此肌红蛋白的预测价值可能继发于识别肾功能不全患者。

方法

连续收治的因排除MI且初始心电图无ST段抬高的患者接受了心脏标志物（肌酸激酶[CK]、肌酸激酶同工酶[CK-MB]和肌钙蛋白I[TnI]）的系列评估。入院时和/或3小时后评估肌红蛋白。肾功能不全定义为肌酐清除率<60 mL/分钟。进行多变量分析以确定30天和1年全因死亡率的预测因素。

结果

共3461例患者纳入分析。总体30天和1年死亡率分别为2.4%和9.7%。675例（20%）肌红蛋白升高，421例（12%）CK-MB升高，517例（15%）TnI升高。在993例肾功能不全患者中，43%肌红蛋白升高，17% CK-MB升高，21% TnI升高。30天和1年死亡率的独立预测因素相似，包括年龄≥65岁、既往MI和缺血性心电图，而肌红蛋白是最强的多变量预测因素（比值比[OR] 2.8，95%置信区间[CI] 2.1 - 3.7），包括肾功能不全患者（OR 2.3，95% CI 1.6 - 3.4）。肌钙蛋白I具有临界预测价值（P = 0.08，OR 1.4，95% CI 0.96 - 2.0），而CK-MB在两组中均无预测价值。