1 Clinical Trials for Various Conditions
In summary, the investigators propose to study elite Croatian breath-hold and SCUBA divers. The investigators will quantify breath-hold hypoxia- and SCUBA diving-induced pulmonary hypertension and right heart function to investigate the relationships between PFO and IPAVA blood flow. The investigators will use a placebo-controlled intervention (sildenafil) to reduce pulmonary arterial pressure in these subjects to examine the impact of the change in pressure (or absence of change) on the relationships determined above.