Water Ingestion for Heart Transplant Patients

Not currently recruiting at 1 trial location

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Satish R. Raj

Disqualifiers: Tricuspid regurgitation, Advanced renal disease, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how drinking a specific amount of water affects heart transplant patients. Researchers aim to determine if quickly drinking 16 ounces of water can alter blood flow. The trial targets individuals who have undergone a heart transplant and are scheduled for a specific heart test. Participants should not have major health issues that make drinking water risky. As an unphased trial, this study provides a unique opportunity to contribute to understanding how hydration impacts heart health after a transplant.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications.

What prior data suggests that water ingestion is safe for heart transplant patients?

Research shows that drinking water is generally safe for most people. Water is essential for the body to function properly, and most individuals can consume it without issues. The study reports no serious side effects from the amount of water used. Therefore, participating in a study involving water consumption should be safe for most people. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Unlike the standard treatments for heart transplant patients, which mainly involve medications like immunosuppressants to prevent organ rejection, this trial explores something as simple as water ingestion. Researchers are excited about this approach because water is natural, widely accessible, and free from side effects, unlike many medications. The idea is that drinking 16 fl oz of water quickly might have a unique impact on heart function and overall recovery post-transplant. If effective, this could revolutionize supportive care strategies by adding a safe, cost-effective method to enhance patient outcomes.

What evidence suggests that water ingestion might be an effective treatment for heart transplant patients?

This trial will investigate the effects of water ingestion on heart transplant patients. Research has shown that drinking water can affect the body's blood vessels. Studies have found that water consumption can increase resistance in the blood vessels, potentially helping to maintain steady blood pressure. Although direct evidence on the effects of water alone on heart transplant patients is limited, the hypothesis is that water could aid the body in managing blood flow more effectively. This might benefit heart health by supporting stable circulation. However, further research is needed to fully understand its effects on specific groups like heart transplant patients. ^{1 2 5 6 7}

Who Is on the Research Team?

Satish R Raj, MD, MSCI

Principal Investigator

Vanderbilt University Medical Center

Are You a Good Fit for This Trial?

This trial is for heart transplant patients over 18 years old who are scheduled for a clinical right heart catheterization. It's not suitable for those with significant tricuspid regurgitation, difficulty swallowing large amounts of water, or severe kidney disease where drinking water could be harmful.

Inclusion Criteria

I am over 18 years old.

I have had a heart transplant and am scheduled for a heart catheterization.

Exclusion Criteria

I have severe leakage in my heart's tricuspid valve.

I have a serious health condition like advanced kidney disease.

I cannot safely drink 500 ml of water.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants ingest 16 fl oz of water and undergo hemodynamic measurements

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Water

Trial Overview The study is examining the effects of drinking 16 fl oz of water on blood vessel resistance in heart transplant recipients. The goal is to see if consuming this amount of water will increase the resistance in systemic blood vessels.

How Is the Trial Designed?

Group I: 1 Experimental Treatment 1 Intervention

water ingestion (16 fl oz within 3 minutes)

Who Is Running the Clinical Trial?

Satish R. Raj

Lead Sponsor

Trials

7

Recruited

690+

National Center for Research Resources (NCRR)

Collaborator

Trials

540

Recruited

317,000+

Published Research Related to This Trial

Watermelon juice supplementation significantly increased plasma levels of l-citrulline, l-arginine, and nitrite, which are associated with improved nitric oxide bioavailability, but it also raised resting blood pressure compared to control conditions.

Despite the benefits in muscle oxygenation during moderate-intensity exercise, watermelon juice did not enhance time-to-exhaustion during severe-intensity exercise, suggesting it may not be effective for improving endurance performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans. Bailey, SJ., Blackwell, JR., Williams, E., et al.[2018]

Watermelon juice, especially when unpasteurized, enhances the bioavailability of l-citrulline, which is beneficial for reducing muscle soreness in athletes.

In a study with seven athletes, both natural and enriched watermelon juices significantly lowered recovery heart rates and muscle soreness after intense exercise, suggesting their effectiveness as functional drinks for athletic recovery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Watermelon juice: potential functional drink for sore muscle relief in athletes. Tarazona-Díaz, MP., Alacid, F., Carrasco, M., et al.[2013]

Watermelon and its key compound L-citrulline have been shown to reduce blood pressure in human trials, indicating potential cardiovascular benefits.

Emerging evidence suggests that watermelon intake may improve lipid metabolism and glucose homeostasis, with additional benefits for gut health and satiety, although more research is needed to confirm these effects in humans.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Watermelon and L-Citrulline in Cardio-Metabolic Health: Review of the Evidence 2000-2020. Burton-Freeman, B., Freeman, M., Zhang, X., et al.[2023]

In a study with low-density lipoprotein receptor-deficient mice, consumption of watermelon extract ('sentinel') for 12 weeks significantly reduced body weight gain and plasma cholesterol levels, particularly intermediate-/low-density lipoprotein cholesterol.

The extract also improved the balance of pro- and anti-inflammatory cytokines, leading to a reduction in atherosclerosis development in the aortic arch and thoracic regions, without affecting systolic blood pressure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Citrullus lanatus 'sentinel' (watermelon) extract reduces atherosclerosis in LDL receptor-deficient mice. Poduri, A., Rateri, DL., Saha, SK., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9592950/

Effects of l-citrulline supplementation and watermelon ... In conclusion, this meta-analysis provided evidence that longer-term l-citrulline and watermelon consumption may improve vascular function in adults, suggesting ...

2. sciencedirect.com sciencedirect.com/science/article/abs/pii/S0939475321003185

Daily 100% watermelon juice consumption and vascular ... Two 360 mL servings of 100% watermelon juice per day increased circulating lycopene. The four-week intervention did not affect blood pressure or measures of ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9318495/

Current Evidence of Watermelon (Citrullus lanatus) Ingestion ... Watermelon-derived L-citrulline appears as a supplementation that can improve vascular function, including arterial stiffness and blood pressure.

4. researchgate.net researchgate.net/publication/396466633_Watermelon_Nutritional_Composition_with_a_Focus_on_L-Citrulline_and_Its_Cardioprotective_Health_Effects-A_Narrative_Review

(PDF) Watermelon Nutritional Composition with a Focus on ... The beneficial effects of oral L-citrulline ingestion through watermelon require additional evidence, but it has already been demonstrated that ...

5. mdpi.com mdpi.com/2072-6643/17/20/3221

Watermelon Nutritional Composition with a Focus on L- ... The beneficial effects of oral L-citrulline ingestion through watermelon require additional evidence, but it has already been demonstrated that it does not ...

6. mdpi.com mdpi.com/2072-6643/14/24/5199

Wild Watermelon-Extracted Juice Ingestion Reduces ... These data show that acute ingestion of wild watermelon-extracted juice reduces peripheral (lower limb) arterial stiffness and increases NO bioavailability.

7. researchgate.net researchgate.net/publication/269772640_The_effect_of_l_-citrulline_and_watermelon_juice_supplementation_on_anaerobic_and_aerobic_exercise_performance

The effect of l -citrulline and watermelon juice ... Results showed that the supplements did not significantly affect the total number of repetitions, fatigue time, VO2 max, and anaerobic threshold ...