Dietary Nitrate Increases VO2peak and Performance but Does Not Alter Ventilation or Efficiency in Patients With Heart Failure With Reduced Ejection Fraction

J Card Fail. 2018 Feb;24(2):65-73. doi: 10.1016/j.cardfail.2017.09.004. Epub 2017 Sep 12.

Abstract

Background: Patients with heart failure with reduced ejection fraction (HFrEF) exhibit lower efficiency, dyspnea, and diminished peak oxygen uptake (VO2peak) during exercise. Dietary nitrate (NO3-), a source of nitric oxide (NO), has improved these measures in some studies of other populations. We determined the effects of acute NO3- ingestion on exercise responses in 8 patients with HFrEF using a randomized, double-blind, placebo-controlled, crossover design.

Methods and results: Plasma NO3-, nitrite (NO2-), and breath NO were measured at multiple time points and respiratory gas exchange was determined during exercise after ingestion of beetroot juice containing or devoid of 11.2 mmol of NO3-. NO3- intake increased (P < .05-0.001) plasma NO3- and NO2- and breath NO by 1469 ± 245%, 105 ± 34%, and 60 ± 18%, respectively. Efficiency and ventilation during exercise were unchanged. However, NO3- ingestion increased (P < .05) VO2peak by 8 ± 2% (ie, from 21.4 ± 2.1 to 23.0 ± 2.3 mL.min-1.kg-1). Time to fatigue improved (P < .05) by 7 ± 3 % (ie, from 582 ± 84 to 612 ± 81 seconds).

Conclusions: Acute dietary NO3- intake increases VO2peak and performance in patients with HFrEF. These data, in conjunction with our recent data demonstrating that dietary NO3- also improves muscle contractile function, suggest that dietary NO3- supplementation may be a valuable means of enhancing exercise capacity in this population.

Keywords: Nitric oxide; VO(2)peak; exercise; heart failure.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Cross-Over Studies
  • Dietary Supplements*
  • Double-Blind Method
  • Exercise Tolerance / physiology*
  • Female
  • Follow-Up Studies
  • Heart Failure / blood
  • Heart Failure / physiopathology
  • Heart Failure / therapy*
  • Humans
  • Male
  • Middle Aged
  • Nitrites / pharmacology*
  • Oxygen / blood*
  • Oxygen Consumption / physiology*
  • Respiration / drug effects*
  • Stroke Volume / physiology*

Substances

  • Nitrites
  • Oxygen