Effects of Lower Extremity Compression Garments on Exercise Heart Function in Adults with Fontan Circulation Aged 18 to 45

What this Trial Is About

Researchers are studying whether wearing venous compression garments can improve exercise stroke volume in patients with Fontan circulation, a specific heart condition. The study tests if both immediate and longer-term use of these garments increases stroke volume during exercise, and whether patients with significant venous varicosities respond more to compression. The study includes patients with Fontan circulation and healthy controls for comparison. Participants receive custom-made lower extremity compression garments based on measurements and undergo testing on three separate days. On day one, consent, screening, and garment measurements occur. On day two, participants have cardiovascular MRI scans with and without the garments during exercise. On day three, cardiovascular and exercise testing is done with and without the garments, including assessments like DEXA, pulmonary function, vascular studies, and echocardiography. A subset of Fontan patients repeats testing after wearing garments for two weeks during waking hours. Throughout the study, participants undergo submaximal exercise testing using MRI and an upright exercise ergometer to measure stroke volume and venous return with and without compression. Measurements include blood pressure, oxygen uptake, and cardiac output at rest and during exercise. Researchers monitor changes acutely and after two weeks of garment use. The total study duration extends to the final follow-up visit about two weeks after initial testing, with ongoing safety monitoring and outcome assessment.

Venous Compression in Fontan