Alveolar Air and O2 Uptake During Exercise in Patients With Heart Failure

JOURNAL OF CARDIAC FAILURE

卷:24

Article

Van Iterson, Erik H.^1,2  Smith, Joshua R.²  Olson, Thomas P.² 

[1] Cleveland Clin, Heart & Vasc Inst, Dept Cardiovasc Med, Prevent Cardiol & Cardiac Rehabil Sect, Cleveland, OH 44106 USA

[2] Mayo Clin, Dept Cardiovasc Med, Rochester, MN USA

关键词: HFrEF;    HFpEF;    O-2 transport;    Exercise intolerance;    Aerobic exercise capacity;    Oxidative capacity;    Metabolic demand;   

DOI  :  10.1016/j.cardfail.2018.08.001

来源: Elsevier

【 摘 要 】

Background: Peak exercise pulmonary oxygen uptake ((V) over dotO(2)) is a primary marker of prognosis in heart failure (HF). The pathophysiology of impaired peak (V) over dotO(2) is unclear in patients. To what extent alveolar airway function affects (V) over dotO(2) during cardiopulmonary exercise testing.(CPET) has not been fully elucidated. This study aimed to describe how changes in alveolar ventilation ((V) over dot(A)), volume (V-A), and related parameters couple with exercise (V) over dotO(2) in HF. Methods and Results: A total of 35 patients with HF (left ventricular ejection fraction 20 +/- 6%, age 53 +/- 7 y) participated in CPET with breath-to-breath measurements of ventilation and gas exchange. At rest, 20 W, and peak exercise, arterial CO2 tension was measured via radial arterial catheterization and used in alveolar equations to derive (V) over dot(A) and V-A. Resting lung diffusion capacity for carbon monoxide (DLCO) was assessed and indexed to V-A for each time point. Resting R-2 between (V) over dotO(2) and (V) over dot(A), V-A, DLCO, and DLCO/V-A was 0.68, 0.18, 0.20, and 0.07, respectively (all P < .05 except DLCO/V-A). 20 W R-2 between (V) over dotO(2) and (V) over dot(A), V-A, DLCO, and DLCO/V-A was 0.64, 0.32, 0.07, and 0.18 (all P < .05 except DLCO). Peak exercise R-2 between (V) over dotO(2) and V-A, V-A, DLCO, and DLCO/V-A was 0.55, 0.31, 0.34, and 0.06 (all P < .05 except DLCO/V-A). Conclusions: These data suggest that alveolar airway function that is not exclusively related to effects caused by localized lung diffusivity affects exercise (V) over dotO(2) in moderate-to-severe HF.

【 授权许可】

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