SAN FRANCISCO – Baroreflex activation therapy met all four of its primary endpoints in its U.S. pivotal trial of 264 patients with advanced heart failure with reduced ejection fraction who were ineligible for cardiac resynchronization therapy.
The results showed that ongoing baroreflex activation therapy (BAT) via a single, stimulating electrode surgically placed on a patient’s carotid artery led to statistically significant and clinically meaningful improvements in quality of life and functional capacity while also reducing the level of a biomarker of heart failure severity in patients already on guideline-directed medical therapy, Michael R. Zile, MD, said at the annual scientific sessions of the Heart Rhythm Society. He estimated that the device is appropriate for perhaps a third or more of patients with heart failure with reduced ejection fraction (HFrEF), specifically patients with New York Heart Association functional class III disease who are not candidates for treatment with cardiac resynchronization therapy (CRT) and with a blood level of N-terminal pro–brain natriuretic peptide (NT-proBNP) of less than 1,600 pg/mL, a cutoff that excludes patients with very severe class III HFrEF and focuses on those who benefited in the study.
“To our knowledge, this is the first successful pivotal trial of device-based neuromodulation therapy in HFrEF patients,” said Dr. Zile, professor of medicine at the Medical University of South Carolina in Charleston. “We think that BAT fills an unmet need” in a large number of HFrEF patients. He stressed that the placement of the single, 2-mm, unilateral electrode on the baroreceptor-containing carotid sinus is an “extremely safe and simple” surgery. The electrode attaches to a small, subcutaneously placed generator.
Dr. Zile attributed the treatment’s success, in contrast to a prior, failed attempt to treat HFrEF by vagus nerve stimulation (J Am Coll Cardiol. 2016 Jul 12;68[2]:147-56) to BAT’s action via the patient’s brain, which processes the afferent signal it receives from stimulation to in turn inhibit sympathetic activation and upregulate parasympathetic innervation, with both actions benefiting HFrEF patients. “The integrated autonomic balance is the real difference with this device,” he said. Other helpful effects from BAT are reduced heart rate, reduced cardiac remodeling, increased vasodilation, a decrease in elevated blood pressure, increased diuresis, and a drop in renin secretion. The pivotal trial built on findings from a phase 2 study (JACC Heart Fail. 2015 Jun;3[6]:487-96).