Dietary Nitrate for Heart Failure

For all studies and sub-studies:

1. All Subjects will be consented. B) All Subjects will give permission for the investigators to review their medical records.

For the BRJ main study (acute dose BRJ intervention):

1. After consenting to participate, subjects will be instructed to refrain from spitting or the use of an antibacterial mouthwash, antacids, proton pump inhibitors, or chewing gum during the study.
2. Subjects will be asked to answer questionnaires regarding their medical health (basic health questionnaire, Minnesota living with heart failure questionnaire, a magnetic resonance safety -i.e., questions regarding implanted pacemakers, etc...) 2a)Subjects will undergo a physical examination at one time during the study.
3. Subjects will be interviewed by a dietician with regards to their typical dietary intake and instructed on a low nitrate diet.
4. In study visit #1 subjects will be randomized to receive either a "shot" of BRJ (James White Drinks)or placebo (BRJ without nitrates).
5. Before and at 3 time points (~hourly) after receiving the BRJ or placebo, subjects will undergo phlebotomy for plasma nutrient/hormone levels and will have their blood pressure checked. They will also be asked to swish (5 minutes) and spit out a dilute ~ 4tbps solution of nitrate,so we can quantify nitrate to nitrite conversion at ~ 1 1/4 hours after ingestion 5A) Subjects will undergo an echocardiogram just after the swish and spit.
6. ~ 1 3/4 hours after ingestion, subjects will undergo a 6 minute walk.
7. ~ 2 hours after ingestion, subjects will pedal an ergometer for 6 min at 15, 30, and 45 W (requiring ~50, ~60, and ~70% of oxygen consumption (VO2) peak, i.e., peak oxygen consumption) while VO2 is measured using a ParvoMedics TrueOne (this is the brand) metabolic cart. Five min of rest will be allowed between stages. The average VO2 during the last 2 min of each stage will be used to calculate gross and delta efficiency using stoichiometric equations as previously described. Following a 10 min rest period, peak power and VO2 peak will determined during a continuous exercise test performed using a 10 W/min ramp protocol.
8. Subjects will then (immediately afterwards )undergo an Magnetic resonance (MR) study of skeletal muscle (and if there is time cardiac performance) with mild exercise (pushing one foot on a pedal for 6 min of submaximal isometric exercise (1 s contraction at 50% of previously-determined maximal voluntary contraction - according to their VO2 peak levels in their medical charts - every 9 s) with spectra acquired before, during, and after exercise. During exercise, subjects will have their heart rate, blood pressure and rhythm monitored.
9. Subjects will be asked to undergo a mouth swab for bacterial DNA analyses (after the swish and spit) 9A) Subjects will undergo a Dual-energy Xray absorptiometry (DXA) scan for body composition analysis (either before or after BRJ ingestion - it is a phenotyping measure - not an endpoint)
10. Subjects will undergo a 7 d wash-out period
11. Subjects will come in for study day 2 in which they will receive whichever treatment (BRJ or placebo) that they did not receive at first and then repeat the studies listed above 5)-9). (The total time of the study is estimated to take 5 hours)

For the longer 2 (or 4) week BRJ substudy: (subjects include HF (heart failure) patients and nonHF controls, i.e., those without heart failure)

1. Subjects will be asked to undergo steps 1-9 above, ingest 1 week of BRJ (1 "shot"/day) and then undergo the studies listed 5)-9).
2. Subjects will be asked to ingest 1 more week of BRJ (1 "shot"/day for a total of 2 weeks) and then undergo a repeat of studies listed 5)-9)

For the BRJ neuromuscular function testing sub-study:

1. Subjects will be asked to undergo steps 1-6 above
2. Subjects will be asked to undergo a mouth swab for bacterial DNA analyses.
3. Subjects will undergo a test of neuromuscular function using an isokinetic dynamometer (a device that measures voluntary muscle force production while controlling the speed of movement) immediately after the echocardiogram at ~2 h after BRJ (or placebo ingestion).

3A) Subjects will be asked to undergo an optional skeletal muscle biopsy immediately after the Biodex study.

3B) Subjects will undergo a dual-energy isokinetic dynamometry study for body composition analysis (at any time point during the study day).

1. Subjects will undergo a 7 d washout period.
2. Subjects will come in for Study day 2 in which they will receive whichever treatment (BRJ or placebo) they did not receive at first and then repeat the studies listed above 1-3.

For the Pulmonary artery (PA) pressure sub-study:

NOTE: This study will only be performed in patients who are undergoing a PA catheter placement for clinical purposes (high PA pressures) anyway.

1. After consenting to participate, subjects will be instructed to refrain from spitting or the use of an antibacterial mouthwash, antacids, proton pump inhibitors, or chewing gum during the study.
2. Subjects will be asked to answer questionnaires regarding their medical health (basic health questionnaire, Minnesota living with heart failure questionnaire, etc.) 2a) Subjects will be asked to undergo a physical examination.
3. Before and at 3 (hourly) time points after receiving a "shot" of BRJ, subjects will undergo phlebotomy for plasma nutrient/hormone levels and will have their blood pressure checked and will blow into a tube connected to a small machine that will measure the amount of nitric oxide in their breath. Subjects will also have cardiovascular measurements (e.g., cardiac output, PA pressure, etc.) made before and at 3 ~ hourly time points after receiving the BRJ. These measurements will be made using a PA catheter that is being placed for clinical purposes.
4. If a subject is to undergo an LVAD placement he/she will be randomized to receive BRJ or placebo the evening before surgery (anticipated average ~ 8-12 hours before), and then the LV core will be harvested and immediately frozen for later analysis.
5. Subjects who will be undergoing myocardial perfusion studies will undergo the same basic studies (breath NO, plasma nitrate/nitrite determination, as mentioned in the neuromuscular aim, but subjects will also undergo a positron emission tomography (PET) study in which they will receive O-15 water for quantification of myocardial blood flow ~ 2 hours after consumption of BRJ or placebo. Then they will undergo a washout phase of 7 d and then repeat the PET study after the other treatment (BRJ or placebo).