Woessner 2020 Thesis
| Mary N. Woessner (2020) BEET-HF: the effects of dietary inorganic nitrate supplementation on aerobic exercise performance, vascular function, cardiac performance and mitochondrial respiration in patients with heart failure with reduced ejection fraction. PhD Thesis 198. |
Woessner Mary N, Levinger Itamar, Allen Jason D, McIlvenna Luke C, Neil Christopher (2020) PhD Thesis
Abstract: Heart failure with reduced ejection fraction (HFrEF) is a common end point for patientswith coronary artery disease and it is characterized by exercise intolerance due, in part, to a reductionin cardiac output. Nitric oxide (NO) plays a vital role in cardiac function and patients with HFrEFhave been identified as having reduced vascular NO. This pilot study aimed to investigate if nitratesupplementation could improve cardiac measures during acute, submaximal exercise. Five maleparticipants (61±3 years) with HFrEF (EF 32±2.2%) completed this pilot study. All participantssupplemented with inorganic nitrate (beetroot juice) or a nitrate-depleted placebo for ~13 days priorto testing. Participants completed a three-stage submaximal exercise protocol on a recumbent cycleergometer with simultaneous echocardiography for calculation of cardiac output (Q), stroke volume(SV), and total peripheral resistance (TPR). Heart rate and blood pressure were measured at restand during each stage. Both plasma nitrate (mean=~1028%,p=0.004) and nitrite (mean=~109%,p=0.01) increased following supplementation. There were no differences between interventions atrest, but the percent change in SV and Q from rest to stage two and stage three of exercise was higherfollowing nitrate supplementation (allp>0.05, ES>0.8). Both interventions showed decreases inTPR during exercise, but the percent reduction TPR in stages two and three was greater followingnitrate supplementation (p=0.09, ES=0.98 andp=0.14, ES=0.82, respectively). There wereclinically relevant increases in cardiac function during exercise following supplementation withnitrate. The findings from this pilot study warrant further investigation in larger clinical trials.
Labels:
