多巴酚丁胺负荷试验中左房功能储备对扩张型心肌病患者预后价值的初步观察。

Preliminary observations of prognostic value of left atrial functional reserve during dobutamine infusion in patients with dilated cardiomyopathy.

机构信息

Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.

出版信息

J Am Soc Echocardiogr. 2014 Apr;27(4):430-9. doi: 10.1016/j.echo.2013.12.016. Epub 2014 Jan 31.

DOI:10.1016/j.echo.2013.12.016

PMID:24491673

Abstract

BACKGROUND

The importance of left atrial (LA) functional reserve in patients with depressed left ventricular function remains unclear. Thus, the aim of this study was to test the hypothesis that diminished augmentation of LA function during dobutamine stress might be associated with cardiovascular events in patients with dilated cardiomyopathy.

METHODS

Eighty-four patients with dilated cardiomyopathy with a mean ejection fraction of 34 ± 9% were retrospectively recruited, and LA strain was determined as the averaged global speckle-tracking longitudinal strain from apical four-chamber and two-chamber views during dobutamine stress (20 μg/kg/min). The systolic component of LA strain was considered to reflect reservoir function, whereas the passive and active emptying components were considered to reflect passive and active emptying function, respectively. Event-free survival was tracked for 17 months.

RESULTS

Multivariate Cox proportional-hazards analysis identified LA volume index (hazard ratio [HR], 1.060; P < .001) and β-blocker use (HR, 0.048; P < .05) as the independent variables associated with cardiovascular events among the baseline parameters and changes in systolic LA strain (HR, 0.971; P = .02), in passive emptying LA strain (HR, 0.942; P < .001), and in left ventricular early diastolic strain rate (HR, 0.986; P = .03) under dobutamine as the variables among the functional reserve parameters. In sequential Cox models, a model based on clinical variables (χ(2) = 9.3) was improved by conventional echocardiographic parameters (χ(2) = 19.2, P = .012) and LA strain parameters at rest (χ(2) = 40.1, P = .005) and further improved by the addition of changes in LA strain parameters under dobutamine (χ(2) = 61.6, P < .001).

CONCLUSIONS

The assessment of LA reservoir and passive emptying function during dobutamine stress provides important incremental prognostic value in patients with dilated cardiomyopathy.

摘要

背景

左心房（LA）功能储备在左心室功能降低的患者中的重要性尚不清楚。因此，本研究的目的是检验假设，即在扩张型心肌病患者中，多巴酚丁胺应激期间 LA 功能增强减少可能与心血管事件相关。

方法

回顾性招募 84 名扩张型心肌病患者，平均射血分数为 34 ± 9%，使用多巴酚丁胺（20 μg/kg/min）从心尖四腔和两腔视图确定 LA 应变，LA 应变的收缩成分被认为反映储备功能，而被动排空和主动排空成分分别被认为反映被动排空和主动排空功能。17 个月后进行无事件生存追踪。

结果

多变量 Cox 比例风险分析确定 LA 容积指数（危险比[HR]，1.060；P <.001）和β受体阻滞剂的使用（HR，0.048；P <.05）是基线参数和收缩期 LA 应变（HR，0.971；P =.02）、被动排空 LA 应变（HR，0.942；P <.001）和左心室早期舒张应变率（HR，0.986；P =.03）变化之间与心血管事件相关的独立变量。在序贯 Cox 模型中，基于临床变量的模型（χ²= 9.3）通过常规超声心动图参数（χ²= 19.2，P =.012）和静息时 LA 应变参数（χ²= 40.1，P =.005）得到改善，并通过添加多巴酚丁胺下 LA 应变参数的变化进一步得到改善（χ²= 61.6，P <.001）。