QT离散度作为心脏移植等待患者风险的标志物。

QT dispersion as a marker of risk in patients awaiting heart transplantation.

作者信息

Pinsky D J, Sciacca R R, Steinberg J S

机构信息

Department of Medicine, Columbia-Presbyterian Medical Center, New York, New York 10032, USA.

出版信息

J Am Coll Cardiol. 1997 Jun;29(7):1576-84. doi: 10.1016/s0735-1097(97)00072-7.

DOI:10.1016/s0735-1097(97)00072-7

PMID:9180122

Abstract

OBJECTIVES

The objectives of this study were to determine whether a signal-averaged electrocardiogram (SAECG) or measurement of interlead variability of QT intervals on an electrocardiogram (ECG) obtained at the time of wait-listing could provide prognostic value with respect to cardiac death during the waiting period.

BACKGROUND

Because heart transplantation is a life-saving but limited resource, there remains an urgent need to identify those patients at greatest risk of dying while awaiting heart transplantation as part of the strategy to optimize the allocation of donor organs to those in greatest need. This study was undertaken to prospectively identify clinical, ECG or SAECG variables that might predict mortality during the waiting period.

METHODS

Of 108 consecutive patients referred for heart transplant evaluation, 80 were placed on a waiting list, at which time a standard 12-lead ECG and a SAECG were recorded. In this cohort of 80 patients, QT dispersion was characterized from the 12-lead ECG as either the maximal-minimal QT interval (QTDISP) or as the coefficient of variation of all QT intervals (QTCV).

RESULTS

During the 25-month follow-up period (mean time on waiting list, 201 days), the mortality rate was 27%/year, divided equally between heart failure and sudden deaths. No clinical variable identified at entry predicted mortality. QTDISP and QTCV were strong mortality predictors, with a 4.1-fold increase in mortality in patients with QTDISP > 140 ms compared with those patients with QTDISP < or = 140 ms (95% CI 1.1 to 14.9), whereas a QTCV > or = 9% also predicted a 4.1-fold increased risk of death (95% CI 1.4 to 11.8). Although 88% of all SAECGs were abnormal, no patient with a normal SAECG died suddenly during the waiting period.

CONCLUSIONS

Indexes of QT dispersion provide a means of stratifying a patient's risk of dying while awaiting heart transplantation and may help to establish priority on a heart transplant waiting list.

摘要

目的

本研究的目的是确定在列入等待名单时所获得的信号平均心电图（SAECG）或心电图（ECG）上QT间期的导联间变异性测量是否能为等待期内心脏死亡提供预后价值。

背景

由于心脏移植是一种挽救生命但资源有限的治疗手段，因此迫切需要识别那些在等待心脏移植期间死亡风险最高的患者，这是优化将供体器官分配给最需要者策略的一部分。本研究旨在前瞻性地识别可能预测等待期死亡率的临床、心电图或SAECG变量。

方法

在连续108例接受心脏移植评估的患者中，80例被列入等待名单，此时记录标准12导联心电图和SAECG。在这80例患者队列中，从12导联心电图中确定QT离散度，以最大-最小QT间期（QTDISP）或所有QT间期的变异系数（QTCV）来表示。

结果

在25个月的随访期内（平均等待名单时间为201天），死亡率为每年27%，心力衰竭和猝死各占一半。入组时确定的任何临床变量均不能预测死亡率。QTDISP和QTCV是强有力的死亡率预测指标，QTDISP>140 ms的患者死亡率比QTDISP≤140 ms的患者增加4.1倍（95%CI 1.1至14.9），而QTCV≥9%也预测死亡风险增加4.1倍（95%CI 1.4至11.8）。尽管所有SAECG中有88%异常，但SAECG正常的患者在等待期内均未猝死。