在接受心脏移植评估的慢性心力衰竭患者中，递增运动期间的周期性呼吸可预测死亡率。

Periodic breathing during incremental exercise predicts mortality in patients with chronic heart failure evaluated for cardiac transplantation.

作者信息

Leite Joao J, Mansur Alfredo J, de Freitas Humberto F G, Chizola Paulo R, Bocchi Edimar A, Terra-Filho Mario, Neder J Alberto, Lorenzi-Filho Geraldo

机构信息

Division of Respiratory Disease-Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil.

出版信息

J Am Coll Cardiol. 2003 Jun 18;41(12):2175-81. doi: 10.1016/s0735-1097(03)00460-1.

DOI:10.1016/s0735-1097(03)00460-1

PMID:12821243

Abstract

OBJECTIVES

We hypothesized that exercise-related periodic breathing (EPB) would be associated with poor prognosis in advanced chronic heart failure (CHF).

BACKGROUND

Patients with CHF might present instability of the ventilatory control system characterized by cyclic waxing and waning of tidal volume (periodic breathing [PB]). This condition is associated with several deleterious circulatory and neuro-endocrine responses; in fact, PB in awake and asleep patients has been identified as an independent risk factor for cardiac death. During exercise, however, the prognostic value of PB is still unknown in CHF patients awaiting heart transplantation.

METHODS

Eighty-four patients with established CHF (65 male, 19 female) were submitted to clinical evaluation, echocardiogram, ventricular scintigraphy, determination of resting serum norepinephrine levels, and an incremental cardiopulmonary exercise test on cycle ergometer. Patients were followed for up to 49.7 months (median = 15.3), and 26 patients (30.9%) died during this period.

RESULTS

Twenty-five of 84 patients presented EPB (29.7%). The following variables were related to mortality according to Kaplan-Meier and univariate Cox regression analysis: EPB (p = 0.004), New York Heart Association class (p = 0.04), serum norepinephrine (p = 0.06), peak oxygen uptake (ml.min(-1).kg(-1) and % predicted; p = 0.085 and p = 0.10, respectively), slope of the ratio of change in minute ventilation to change in carbon dioxide output during exercise (p = 0.10), and scintigraphic left ventricular ejection fraction (p = 0.10). Cox multivariate analysis identified EPB as the only independent variable for cardiac death prediction (p = 0.007). Therefore, EPB alone was associated with a 2.97-fold increase in risk of death in this population (95% confidence interval = 1.34 to 6.54).

CONCLUSIONS

Exercise-related periodic breathing independently predicts cardiac mortality in CHF patients considered for heart transplantation.

摘要

目的

我们推测运动相关性周期性呼吸（EPB）与晚期慢性心力衰竭（CHF）的不良预后相关。

背景

CHF患者可能存在通气控制系统不稳定，表现为潮气量的周期性增减（周期性呼吸[PB]）。这种情况与多种有害的循环和神经内分泌反应相关；事实上，清醒和睡眠患者的PB已被确定为心源性死亡的独立危险因素。然而，在等待心脏移植的CHF患者中，运动期间PB的预后价值仍不清楚。

方法

84例确诊CHF患者（65例男性，19例女性）接受了临床评估、超声心动图、心室闪烁显像、静息血清去甲肾上腺素水平测定以及在功率自行车上进行的递增心肺运动试验。对患者进行了长达49.7个月的随访（中位数=15.3），在此期间有26例患者（30.9%）死亡。

结果

84例患者中有25例出现EPB（29.7%）。根据Kaplan-Meier和单因素Cox回归分析，以下变量与死亡率相关：EPB（p = 0.004）、纽约心脏协会分级（p = 0.04）、血清去甲肾上腺素（p = 0.06）、峰值摄氧量（ml·min⁻¹·kg⁻¹和预测值百分比；分别为p = 0.085和p = 0.10）、运动期间分钟通气量变化与二氧化碳排出量变化比值的斜率（p = 0.10）以及闪烁显像左心室射血分数（p = 0.10）。Cox多因素分析确定EPB是预测心源性死亡的唯一独立变量（p = 0.007）。因此，仅EPB就使该人群的死亡风险增加了2.97倍（95%置信区间=1.34至6.54）。