Chronic Stable Angina
Conditions
Brief summary
Previous studies have shown that interventions which modestly increase blood nitrite\_ improve skeletal muscle function on exercise while sparing oxygen, and have been also shown to open up the blood flow during periods of oxygen deprivation. Inorganic nitrate in the diet is absorbed into the bloodstream, concentrated and reduced by bacteria in the mouth to nitrite, which is then absorbed into the bloodstream. . The purpose of this study is to look at the effects of oral inorganic nitrate supplementation on clinical markers of heart ischaemia and the frequency of angina.
Interventions
DRUGSodium Nitrate
DRUGPlacebo
Sponsors
University of Aberdeen
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients aged 18 and over with chronic stable angina (≥2 months duration). Inclusion Criteria Following screening visit: * A positive exercise ECG (1mmSTD at J+0.08 seconds) on a modified Bruce protocol treadmill exercise test. * A positive dobutamine stress echocardiogram, * and/or a positive myocardial perfusion scan (MPI), * and/or a positive coronary angiogram.
Exclusion criteria
* Unable to do exercise test * Women of child bearing potential * If of a racial origin at risk of glucose-6-phosphate dehydrogenase (G6PD) deficiency, G6PD will be excluded prior to inclusion in the study * Resting STD\>=1mm * NYHA 3 or 4 HF or LVEF\<45% * Myocardial infarction or revascularisation within the last two months * Left bundle branch block (LBBB)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time to 1mm ST depression | 12 weeks | The primary outcome is to assess whether oral nitrate treatment increase the time to 1mm ST depression on a modified Bruce protocol exercise test |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in TDI systolic peak velocity | 12 weeks | Change in Tissue Doppler Imaging (TDI) systolic peak velocity in ischaemic wall segments |
| Angina frequency | 12 weeks | Angina frequency |
| GTN use frequency | 12 weeks | GTN use frequency |
| Onset of chest pain | 12 weeks | Time to onset of chest pain on a modified Bruce protocol exercise test |
| Nitrate/Nitrite | 12 weeks | Measurements of Nitrate and Nitrite in plasma |
| Metabolic, inflammatory and angiogenic plasma markers | 12 weeks | Measurements of metabolic, inflammatory and angiogenic markers in plasma |
| Questionnaire Score | 12 weeks | Modified Seattle Angina Questionnaire Score |
Countries
United Kingdom
Outcome results
None listed