Baroreflex activation therapy (BAT) is electrical stimulation delivered by an implanted device, similar to a cardiac pacemaker. This tested device from CVRx Inc has a carotid sinus lead and a pulse generator. It has been found to safely improve symptoms, exercise capacity and quality of life in patients with NYHA Class III heart failure.
Dr. William Abraham, director of the Division of Cardiovascular Medicine at The Ohio State University Wexner Medical Center, said, "Heart failure patients experience an imbalance in their autonomic nervous system, which plays a role in disease progression and leads to adverse effects on the heart, blood vessels and kidneys. Currently, the optimum drug therapy available is not enough to restore balance for some patients, leaving them highly symptomatic, with reduced quality of life. BAT could prove to be an effective added therapy that can help patients feel better."
During the study, 146 patients with NYHA Class III heart failure and a left ventricular ejection fraction of 35% or less at 45 centers in the United States, Canada and Europe were randomly divided into a control group of 70 patients who received medical therapy alone, and a treatment group of 76 patients who received BAT and medical therapy.
Six months later, researchers reassessed all the patients for NYHA Class, quality of life using the Minnesota Living with Heart Failure Questionnaire and exercise capacity using a standardized 6-minute hall walk test. Among those assigned to BAT, more than 50% improved at least one NYHA Class, compared to just 25% of the control group. The treatment group also reported improved quality of life scores and walked approximately 60 meters farther in 6-minutes, compared to the control group. Researchers also noted favorable changes in bio-markers among those treated with BAT.
The research team reported the device was safely implanted with few complications and no adverse effects. The risk of unfavorable cardiovascular or neurological events over the 6-month trial period was the same as similar device-based therapies.
Abraham said, "If these findings are confirmed in larger studies, BAT could be a new option for treating advanced stages of the disease. While it was not intended to evaluate clinical outcomes, Abraham says results from this study support the notion that BAT can reduce heart failure hospitalizations and the number of days hospitalized. However, further research is needed to confirm that."
The study was presented at the American College of Cardiology Annual Scientific Session and is also published in the Journal of the American College of Cardiology Heart Failure