微伏级T波交替在缺血性心肌病患者危险分层中的预后价值

Prognostic utility of microvolt T-wave alternans in risk stratification of patients with ischemic cardiomyopathy.

作者信息

Chow Theodore, Kereiakes Dean J, Bartone Cheryl, Booth Terri, Schloss Edward J, Waller Theodore, Chung Eugene S, Menon Santosh, Nallamothu Brahmajee K, Chan Paul S

机构信息

The Lindner Clinical Trial Center at the Christ Hospital and the Ohio Heart & Vascular Center, Cincinnati, Ohio, USA.

出版信息

J Am Coll Cardiol. 2006 May 2;47(9):1820-7. doi: 10.1016/j.jacc.2005.11.079. Epub 2006 Apr 19.

DOI:10.1016/j.jacc.2005.11.079

PMID:16682307

Abstract

OBJECTIVES

The purpose of this study was to assess if microvolt T-wave alternans (MTWA) is an independent predictor of mortality in patients with ischemic cardiomyopathy.

BACKGROUND

Microvolt T-wave alternans has been proposed as an effective tool for identifying high-risk patients with ischemic cardiomyopathy who are likely to benefit from implantable cardioverter-defibrillator (ICD) therapy. However, earlier studies have been limited in their ability to control for baseline differences between MTWA-negative and -non-negative (positive and indeterminate) patients.

METHODS

We enrolled 768 consecutive patients with ischemic cardiomyopathy (left ventricular ejection fraction < or =35%) and no prior history of ventricular arrhythmia. All patients underwent baseline MTWA testing and were classified as MTWA negative or non-negative. Multivariable Cox regression analyses, stratified by ICD status, were used to determine the association between MTWA testing and mortality after adjusting for demographic, clinical, and treatment differences between MTWA-negative and -non-negative patients.

RESULTS

We identified 514 (67%) patients with a non-negative MTWA test. After multivariable adjustment, a non-negative MTWA test was associated with a significantly higher risk for all-cause (stratified hazard ratio [HR] = 2.24 [95% confidence interval 1.34 to 3.75]; p = 0.002) and arrhythmic mortality (stratified HR = 2.29 [1.00 to 5.24]; p = 0.049) but not for nonarrhythmic mortality (stratified HR = 1.77 [0.84 to 3.74]; p = 0.13). In subgroup analyses, a non-negative MTWA test was also associated with a higher risk for all-cause mortality in patients with ejection fractions < or =30% (stratified HR = 2.10 [1.18 to 3.73]; p = 0.01) and after excluding those with indeterminate MTWA tests (stratified HR = 2.08 [1.18 to 3.66]; p = 0.01).

CONCLUSIONS

Microvolt T-wave alternans is a strong and independent predictor of all-cause and arrhythmic mortality in patients with ischemic cardiomyopathy.

摘要

目的

本研究旨在评估微伏级T波交替（MTWA）是否为缺血性心肌病患者死亡率的独立预测因素。

背景

微伏级T波交替已被提议作为一种有效工具，用于识别可能从植入式心脏复律除颤器（ICD）治疗中获益的缺血性心肌病高危患者。然而，早期研究在控制MTWA阴性和非阴性（阳性和不确定）患者之间的基线差异方面能力有限。

方法

我们纳入了768例连续的缺血性心肌病患者（左心室射血分数≤35%），且这些患者既往无室性心律失常病史。所有患者均接受了基线MTWA检测，并被分类为MTWA阴性或非阴性。采用多变量Cox回归分析，按ICD状态分层，以确定在调整MTWA阴性和非阴性患者之间的人口统计学、临床和治疗差异后，MTWA检测与死亡率之间的关联。

结果

我们确定了514例（67%）MTWA检测为非阴性的患者。经过多变量调整后，MTWA检测为非阴性与全因死亡风险显著升高相关（分层风险比[HR]=2.24[95%置信区间1.34至3.75]；p=0.002）以及心律失常性死亡风险升高相关（分层HR=2.29[1.00至5.24]；p=0.049），但与非心律失常性死亡风险无关（分层HR=1.77[0.84至3.74]；p=0.13）。在亚组分析中，MTWA检测为非阴性在射血分数≤30%的患者中（分层HR=2.10[1.18至3.73]；p=0.01）以及在排除MTWA检测不确定的患者后（分层HR=2.08[1.18至3.66]；p=0.01）也与全因死亡风险升高相关。