Effect of increased inspired oxygen on exercise performance in patients with heart failure and normal ejection fraction

Shah, P., Pellicori, P. , Rimmer, S., Rigby, A. S. and Clark, A. L. (2018) Effect of increased inspired oxygen on exercise performance in patients with heart failure and normal ejection fraction. International Journal of Cardiology, 268, pp. 166-169. (doi: 10.1016/j.ijcard.2018.05.029) (PMID:29803343)

Abstract

Introduction: We investigated whether increased concentrations of inspired oxygen (Fio2) affect exercise tolerance in patients with heart failure and normal ejection fraction (HeFNEF). Methods: 46 patients (mean age 75 years (63% male) and median NTproBNP 1432 (interquartile range: 543–2378 ng/l)) with HeFNEF (defined as signs or symptoms of heart failure requiring treatment with diuretics, with a left ventricular ejection fraction of >45% by echocardiography and amino terminal pro brain natriuretic peptide (NTproBNP) >220 ng/l) completed three maximal incremental exercise tests with different Fio2 (21%, 28% and 40%) in random order. Fio2 was controlled by investigator but blinded to patients. The primary outcome was exercise time (ET). Results: Increasing Fio2 significantly increased exercise time (522 ± 180 s for 21% to 543 ± 176 s, and 542 ± 177 s, for 28% and 40%, respectively, P = 0.04) with no difference in peak workload (57 ± 25 W, 58 ± 25 W and 57 ± 25 W, for 21%, 28% and 40%, respectively, P = 0.50). There was an increase in oxygen saturation but no change in peak heart rate with increasing Fio2. Compared to patients with LVEF ≥50%, patients with LVEF between 45 and 49% had a significantly greater exercise time and peak workload. There was a correlation between the difference in exercise time between Fio2 21% and 40% and age; but not with BMI, haemoglobin, creatinine or NTproBNP. Conclusion: Increasing Fio2 during exertion leads to a small increase in exercise time in patients with HeFNEF.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Pellicori, Dr Pierpaolo
• Authors: Shah, P., Pellicori, P., Rimmer, S., Rigby, A. S., and Clark, A. L.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Robertson Centre
• Journal Name: International Journal of Cardiology
• Publisher: Elsevier
• ISSN: 0167-5273
• ISSN (Online): 1874-1754
• Published Online: 11 May 2018
• Copyright Holders: Copyright © 2018 Elsevier B.V.
• First Published: First published in International Journal of Cardiology 268: 166-169
• Publisher Policy: Reproduced in accordance with the publisher copyright policy