‘Beyond our classical thinking’
It’s “impressive” that such right-GSN ablation seemed to reduce exercise-filling pressures, but one should be circumspect because “it’s way beyond our classical thinking,” Wilfried Mullens, MD, PhD, Hospital Oost-Limburg, Genk, Belgium, said as a panelist after Dr. Fudim’s presentation.
“These are invasive procedures,” he noted, “and our physiological understanding does not always match up with what we’re doing in real life, if you look at other interventional procedures, like renal denervation, which showed neutral effects, or if you look at even interatrial shunt devices, which might even be dangerous.”
The field should be “very prudent” before using SAVM in practice, which shouldn’t be “before we have sufficient data to support the efficacy and safety,” Dr. Mullens said. “It remains to be seen how treatment success will be defined. Is it during exercise? How long does the treatment last? What is the effect of the treatment over time; is it not harmful? These are things that we don’t know yet.”
The procedure was considered successful in all 18 patients, 14 of whom were women and 16 of whom were in NYHA class 3. Their average age was 75, and their mean left ventricular ejection fraction (LVEF) at baseline was 61%. The primary efficacy endpoints were a reduction in PCWP at rest, with legs raised, and at 20W exercise at 1 month. Their baseline invasively measured peak exercise PCWP was at least 25 mm Hg.
At 1 month, mean PCWP at 20W exercise fell from 36.4 mm Hg to 28.9 mm Hg (P = .007) and peak PCWP declined from 39.5 mm Hg to 31.9 mm Hg (P = .013); resting PCWP wasn’t significantly affected. Twelve patients improved by at least one NYHA functional class (P = .02).
Scores on the Kansas City Cardiomyopathy Questionnaire (KCCQ), which assesses quality of life, improved by 22 points at 1 month and 18.3 points at 3 months (P < .01 for both differences).
No significant effects on 6-minute walk distance or natriuretic peptide levels were observed, nor were any observed on LVEF or echocardiographic measures of diastolic function, left ventricular (LV) atrial volume, or LV mass at 3 months.
Three “nonserious” device-related adverse events were observed, including one case of acute decompensation early in the experience, ostensibly due to excessive saline administration, Dr. Fudim reported. There was also one case of transient periprocedural hypertension and one instance of postprocedure back pain.
The SAVM procedure is performed transvenously and in general is technically “really not that challenging,” Dr. Fudim said. In most cases, the necessary skills would be accessible not only to interventional cardiologists but also heart failure specialists. “I have performed this procedure myself, and I’m a heart failure guy.”
The REBALANCE-HF roll-in phase and main trial are supported by Axon Therapies. Dr. Fudim discloses receiving support from Bayer, Bodyport, and BTG Specialty Pharmaceuticals; and consulting fees from Abbott, Audicor, Axon Therapies, Bodyguide, Bodyport, Boston Scientific, CVRx, Daxor, Edwards LifeSciences, Feldschuh Foundation, Fire1, Gradient, Intershunt, NXT Biomedical, Pharmacosmos, PreHealth, Splendo, Vironix, Viscardia, and Zoll. Dr. Mullens discloses receiving fees for speaking from Medtronic, Abbott, Novartis, Boston Scientific, AstraZeneca, and Boehringer Ingelheim.
A version of this article first appeared on Medscape.com.