Clinical Research to Study Vagus Nerve Stimulation for Heart Failure Patients

Elizabeth Juneman, MD The University of Arizona Sarver Heart Center is participating in a multi-site clinical trial to study whether stimulation of the vagus nerve improves heart function in patients diagnosed with heart failure. Elizabeth Juneman, MD, associate professor of medicine and medical director of the Advanced Heart Disease Program, is the principal investigator at the Tucson site for the study called, “Autonomic Regulation Therapy to Enhance Myocardial Function and Reduce Progression of Heart Failure With Reduced Ejection Fraction” (ANTHEM-HFrEF).

 Eligible patients with symptomatic heart failure and reduced left ventricular ejection fraction are randomized to one of two treatment groups. One group undergoes implantation of the VITARIA system adjacent to a long nerve running from the brain to the chest called the vagus nerve.  The vagus nerve is one of the 12 cranial nerves, running from the brain to structures in the head and upper chest.  The implant is about the size of a very thick credit card and must be added to optimal medical therapy for heart failure. The control group continues to receive medical therapy but does not undergo implantation.  Participants in the trial are randomized to the two groups, meaning the patients and doctors have no control over the group to which a patient will be assigned.

The autonomic nervous system plays a large role in heart failure, said Dr. Juneman. The brain controls the function of the heart through two branches of the autonomic nervous system: the sympathetic branch, which responds as “fight or flight” during stress, similar to adrenaline; and the parasympathetic branch, which allows the body to rest and recover from stress. Parasympathetic nerve fibers run in the vagus nerve to the heart. In normal health, the two branches are said to be in balance.

Patients with heart failure may experience an imbalance between these two stress response branches in which the adrenaline-like sympathetic system is overactive and the “rest” response is underactive. Autonomic Regulation Therapy (ART) applies mild electrical impulses to the vagus nerve to activate the parasympathetic branch and restore balance.

This is one example of the more than 20 clinical research studies underway in Sarver Heart Center’s Cardiovascular Clinical Research Program. To learn more about clinical research at Sarver Heart Center, visit SARVER HEART CENTER CLINICAL RESEARCH