Mechanisms of Altered Ventilatory Control in Heart Failure
Mechanisms of Altered Ventilatory Control in Heart Failure
This study is being done because the investigators are trying to understand how feedback from the muscles can influence your blood pressure and breathing during exercise, and if the investigators can reduce this response in heart failure patients. The investigators are also trying to determine ways to improve tolerance to exercise in heart failure patients.
If you are enrolled in this study the investigators will ask you to make 3 separate study visits.
During study visit 1 you will be asked to get a blood draw, DEXA bone scan, perform pulmonary function tests, and exercise on a stationary bike at maximal exertion while breathing into a mouth piece.
During study visits 2 and 3 you will be asked to again exercise at maximal exertion while breathing into a mouth piece. However, during these two visits you will be receiving an intrathecal injection of fentanyl one day and placebo the other day, randomly selected and you will be blinded as to which you are receiving. A catheter will also be placed in an artery in your arm and a vein in your leg, which will help us to measure blood flow, blood pressure and draw blood when need be. The investigators will also ask you to perform a brief chemosensitivity test, breathing in and out your own air, after you are done exercising.
Inclusion Criteria (Heart Failure Patients):
Control Participants: