NITRATE-OCT
Research type
Research Study
Full title
A randomised, double-blind, placebo-controlled study investigating the effects of dietary nitrate on vascular function, platelet reactivity and restenosis in stable angina
IRAS ID
163989
Contact name
Amrita Ahluwalia
Contact email
Sponsor organisation
Queen Mary University of London
Duration of Study in the UK
2 years, 11 months, 29 days
Research summary
The opening up of blocked coronary arteries using a balloon that is passed through the artery and inflated (called angioplasty) has been a revolutionary technique for improving survival in people with heart disease. However, over time, in 5-10% of patients the treated artery becomes blocked, a phenomenon called restenosis. Recent evidence suggests that dietary nitrate, a chemical found naturally in high levels in green leafy vegetables and beetroot, has a range of biological effects in the body that might reduce restenosis. We have shown previously that nitrate exerts effects on arteries that might prevent a heart attack. In this study we will investigate the effects of increasing dietary nitrate intake in patients having balloon angioplasty by providing a daily load of vegetable that has a high nitrate content in consented patients who have undergone balloon angioplasty. This study will test whether dietary nitrate might be useful in preventing arteries from becoming blocked in patients who are at risk of this happening.
Summary of results
Coronary heart disease is the main cause of death in the UK. Stable angina (narrowing within coronary arteries) is an area of significant morbidity. Patients with stable angina are treated with lifestyle changes and optimal medical therapy. One treatment for stable angina (stable coronary heart disease) is balloon angioplasty with stent implantation (i.e. metal scaffold that opens the blood vessel supplying the heart (coronary artery). This procedure has revolutionised treatment but raises concerns about future complications due to enhanced platelet reactivity (stickiness of the blood) and endothelial dysfunction (process where wall of the coronary arteries become thickened and lose their normal, healthy function). These complications result in restenosis within the stent and blockage of the coronary artery, which results in further heart attacks, strokes, the need for further stent procedures and even death (collectively called major adverse cardiac events; MACE).
This study has found that using inorganic nitrate, specifically beetroot juice, can reduce restenosis of stents in patients with stable angina. The naturally occurring inorganic nitrate in beetroot juice (with a dose of 5 mmol) can be converted to beneficial nitric oxide, which can reduce restenosis, reducing the need for further stent procedures. Furthermore, this study suggested that inorganic nitrate may reduce MACE.REC name
London - Bromley Research Ethics Committee
REC reference
15/LO/0555
Date of REC Opinion
22 May 2015
REC opinion
Further Information Favourable Opinion