Is Blood Flow Through IPAVA and PFO Related to Breath-hold and SCUBA Diving-induced Pulmonary Hypertension?

Age: 18+

Sex: Any

Trial Phase: Phase < 1

Sponsor: University of Oregon

Must not be taking: Sildenafil, Nitrates

Disqualifiers: Coronary artery disease, Pregnancy, others

Compensation: Varies

Number of Visits: 2

82 Participants Needed

Trial Summary

What is the purpose of this trial?

This trial studies elite Croatian breath-hold and SCUBA divers to understand how their lung blood pressure changes during diving. Researchers will use sildenafil to see if it can lower this pressure and improve heart function, especially in those with a small hole in their heart. Sildenafil has been studied for its effects on exercise performance and lung function in various conditions.

Will I have to stop taking my current medications?

If you are taking medication or herbal supplements for heart or respiratory diseases, you must stop them for 48 hours before testing. Also, you cannot participate if you are taking sildenafil, nitrates, or similar products.

What data supports the effectiveness of the drug sildenafil (Viagra) for treating erectile dysfunction?

Research shows that sildenafil (Viagra) significantly improves erectile function compared to a placebo, with 74% of patients reporting improved erections versus 16% for placebo. It has been effective in diverse patient groups, including those with diabetes, cardiovascular issues, and other conditions. ^{1 2 3 4 5}

Research Team

Andrew Lovering, PhD

Principal Investigator

University of Oregon

Eligibility Criteria

Inclusion Criteria

People who are exceptional at holding their breath while diving.

People who have gone scuba diving before.

You live close to Split, Croatia.

Exclusion Criteria

Currently taking medication or herbal supplement for any heart or respiratory disease that cannot be ceased for 48 hours prior to testing

Women who are pregnant or trying to become pregnant

You have had heart problems related to blockages in your arteries in the past.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Intervention

Participants receive either sildenafil or placebo to assess its effect on pulmonary arterial pressure and right heart function during breath-hold and SCUBA diving conditions

1 day

1 visit (in-person)

Follow-up

Participants are monitored for changes in pulmonary arterial pressure and right heart function post-intervention

1 hour

1 visit (in-person)

Data Analysis

Analysis of collected data to determine the relationship between PFO, IPAVA blood flow, and pulmonary arterial pressure

Treatment Details

Interventions

• Placebo
• Sildenafil

Participant Groups

Group I: Sildenafil administration Active Control 1 Intervention

Administration of 50mg sildenafil one time, one hour prior to measurements

Group II: Placebo administration Placebo Group 1 Intervention

Administration of 50mg placebo one time, one hour prior to measurements

Who Is Running the Clinical Trial?

University of Oregon

Lead Sponsor

Trials

91

Recruited

46,700+

Findings from Research

The new sildenafil spray demonstrated equivalent bioavailability to the traditional tablet form, but it allowed for a faster onset of action, with maximum concentration reached in 51 minutes compared to 62 minutes for the tablet.

Most adverse events reported during the studies were mild to moderate, indicating that the new spray form is generally safe for use in healthy male volunteers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Pharmacokinetic features of sildenafil spray in healthy men depending on food intake]. Krivoborodov, GG., Zakharov, KA., Vasilyuk, VB., et al.[2022]

In a 12-week study involving 254 men with erectile dysfunction in Egypt and South Africa, sildenafil (Viagra) significantly improved the ability to achieve and maintain erections compared to placebo, with 74% of sildenafil users reporting improved erections versus 27% for placebo (P<0.0001).

Sildenafil was found to be well-tolerated, with common side effects including headache, dyspepsia, and flushing, confirming its efficacy and safety profile consistent with previous global studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and safety of sildenafil citrate (Viagra) for the treatment of erectile dysfunction in men in Egypt and South Africa. Levinson, IP., Khalaf, IM., Shaeer, KZ., et al.[2015]

Sildenafil citrate (Viagra) has been prescribed to over 10 million patients and has shown significant improvements in erectile function across various conditions, including diabetes and cardiovascular disease, based on clinical trials.

The medication is generally well-tolerated, with most side effects being mild or moderate and rarely causing patients to stop treatment, indicating its safety in a wide range of patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Three-year update of sildenafil citrate (Viagra) efficacy and safety. Sadovsky, R., Miller, T., Moskowitz, M., et al.[2022]

In a 12-week study involving 329 men with erectile dysfunction, 74% of those treated with 50 mg sildenafil reported improved erections, compared to only 16% in the placebo group, demonstrating its high efficacy (p < 0.0001).

Sildenafil was well-tolerated, with common side effects like headache and flushing being mild to moderate, and less than 1% of participants discontinued treatment due to adverse events, indicating a favorable safety profile.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and safety of oral sildenafil in the treatment of erectile dysfunction: a double-blind, placebo-controlled study of 329 patients. Sildenafil Study Group. Padma-Nathan, H., Steers, WD., Wicker, PA.[2015]

References

1. United States pubmed.ncbi.nlm.nih.gov

Oral sildenafil citrate (viagra) for erectile dysfunction: a systematic review and meta-analysis of harms. [2018]

2. Russia (Federation) pubmed.ncbi.nlm.nih.gov

[Pharmacokinetic features of sildenafil spray in healthy men depending on food intake]. [2022]

3. England pubmed.ncbi.nlm.nih.gov

Efficacy and safety of sildenafil citrate (Viagra) for the treatment of erectile dysfunction in men in Egypt and South Africa. [2015]

4. India pubmed.ncbi.nlm.nih.gov

Three-year update of sildenafil citrate (Viagra) efficacy and safety. [2022]

5. India pubmed.ncbi.nlm.nih.gov

Efficacy and safety of oral sildenafil in the treatment of erectile dysfunction: a double-blind, placebo-controlled study of 329 patients. Sildenafil Study Group. [2015]