The (Barostim Neo - Baroreflex Activation Therapy for Heart Failure) trial enrolled patients with class III HFrEF with a left ventricular ejection fraction of 35% or less and a 6-minute walk distance of 150-400 m, who were ineligible for CRT, on optimal medical therapy, and who had an elevated NT-proBNP level. After the study randomized 271 patients to either BAT or ongoing medical therapy only (without use of a sham procedure or sham BAT), the results showed a statistically significant benefit for three of the four primary endpoints. Patients treated with BAT for 6 months had statistically significant and clinically meaningful improvements in their quality of life scores as measured on the Minnesota Living With Heart Failure , in their function as measured by the 6-min walk distance, and in the treatment’s safety, based on the combined rate of major adverse neurological and cardiovascular events, which occurred in 6% of patients treated with BAT, which was significantly better than the study’s prespecified performance goal of 15%.
However, for the fourth primary endpoint – reduction in blood levels of NT-proBNP – the BAT-treated patients showed no significant improvement, compared with the controls. The design of BeAT-HF called for consultation with the Food and Drug Administration in such a situation, and further data analysis showed that the problem may have been that some enrolled patients entered with extremely elevated levels of this biomarker. The agency authorized an added protocol that randomized 102 additional patients that matched the initial cohort but had a requirement for an NT-proBNP level of less than 1,600 pg/mL. The 6-month outcomes of these patients were combined with the previously determined outcomes for 162 of the original 271 patients who entered with NT-proBNP levels within the specified limit, producing a total, final study group of 264 patients, of whom 120 received BAT and completed 6-month follow-up, and 125 received medical therapy only and had 6-month follow-up. These patients averaged about 63 years of age, and 20% were women. On average they were on four heart failure medications, and more than three-quarters also had an implanted cardiac device.
The results from an analysis of this cohort showed a statistically significant, 25% relative reduction in blood levels of NT-proBNP in the BAT patients, compared with the controls, and it also confirmed statistically significant and meaningful improvements in quality of life and function on BAT, compared with controls. The 14-point average improvement in the quality of life score in BAT patients, compared with the controls, on the Minnesota Living With Heart Failure Questionnaire was nearly triple the point improvement that’s considered clinically meaningful and hence was “very convincing” about the treatment’s efficacy, noted Dr. Zile, who is also director of cardiology at the VA Medical Center in Charleston. The 25% drop in average NT-proBNP levels “predicts a marked reduction in morbidity and mortality.” He added that researchers have developed a percutaneous, transcatheter method for placing the carotid electrode that will soon undergo clinical testing.
These results “reconfirm the safety of BAT,” but are limited by a relatively short follow-up of 6 months, no data on survival benefit, and by not having echocardiographic data on possible cardiac remodeling, commented, medical director of the Electrophysiology Research Foundation in Warren, N.J.
BeAT-HF was sponsored by CVRx, the company developing the baroreflex activation device. Dr. Zile has been a consultant to CVRx and to Abbott, AstraZeneca, Bayer, Bristol-Myers Squibb, Lilly, Merck, and Novartis. Dr. Saksena had no disclosures.
SOURCE: Zile MR. Heart Rhythm 2019, .