Modulation of Circulating Levels of the Ketone Body 3-hydroxybutyrate in Patients With Chronic Heart Failure: Cardiovascular Effects

The ketone body 3-hydroxybutyrate (3-OHB) is a naturally occurring energy substrate, and is associated with increased life span and improved health. We have previously shown that intravenous 3-OHB treatment increases myocardial blood flow \> 70% in healthy humans and data from our group show that 3-OHB increases cardiac output by 40 % in patients with heart failure. In this study the investigators aim to investigate: 1. If this effect is reproducible with a commercially available oral ketone supplements 2. The safety of commercially available ketone supplements in heart failure patients