Evaluating the Effectiveness of Sildenafil at Improving Health Outcomes and Exercise Ability in People With Diastolic Heart Failure (The RELAX Study)

Duke University Medical Center, Durham

Morehouse School of Medicine, Atlanta

Minnesota Heart Failure Network, Minneapolis

Mayo Clinic, Rochester

Baylor College of Medicine, Houston

University of Utah Health Sciences Center, Murray

Mayo Clinic Arizona, Phoenix

Brigham and Women's Hospital, Boston

University of Vermont - Fletcher Allen Health Care, Burlington

Montreal Heart Institute, Montreal