Endovascular ablation of the right greater splanchnic nerve in heart failure with preserved ejection fraction: early results of the REBALANCE-HF trial roll-in cohort

Abstract

Aims: In heart failure (HF) with preserved ejection fraction (HFpEF), excessive redistribution of blood volume into the central circulation leads to elevations of intracardiac pressures with exercise limitations. Splanchnic ablation for volume management (SAVM) has been proposed as a therapeutic intervention. Here we present preliminary safety and efficacy data from the initial roll-in cohort of the REBALANCE-HF trial.

Methods and results: The open-label (roll-in) arm of REBALANCE-HF will enrol up to 30 patients, followed by the randomized, sham-controlled portion of the trial (up to 80 additional patients). Patients with HF, left ventricular ejection fraction (LVEF) ≥50%, and invasive peak exercise pulmonary capillary wedge pressure (PCWP) ≥25 mmHg underwent SAVM. Baseline and follow-up assessments included resting and exercise PCWP, New York Heart Association (NYHA) class, Kansas City Cardiomyopathy Questionnaire (KCCQ), 6-min walk test, and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Efficacy and safety were assessed at 1 and 3 months. Here we report on the first 18 patients with HFpEF that have been enrolled into the roll-in, open-label arm of the study across nine centres; 14 (78%) female; 16 (89%) in NYHA class III; and median (interquartile range) age 75.2 (68.4-81) years, LVEF 61.0 (56.0-63.2)%, and average (standard deviation) 20 W exercise PCWP 36.4 (±8.6) mmHg. All 18 patients were successfully treated. Three non-serious moderate device/procedure-related adverse events were reported. At 1-month, the mean PCWP at 20 W exercise decreased from 36.4 (±8.6) to 28.9 (±7.8) mmHg (p < 0.01), NYHA class improved by at least one class in 33% of patients (p = 0.02) and KCCQ score improved by 22.1 points (95% confidence interval 9.4-34.2) (p < 0.01).

Conclusion: The preliminary open-label results from the multicentre REBALANCE-HF roll-in cohort support the safety and efficacy of SAVM in HFpEF. The findings require confirmation in the ongoing randomized, sham-controlled portion of the trial.

Keywords: Clinical trial; Heart failure with preserved ejection fraction; Splanchnic nerve ablation; Therapeutics.

Figure 1

Splanchnic ablation for volume management (SAVM) system. (A) Ablation catheter. (B) Access to greater splanchnic nerve via venous system.

Figure 2

Change in pulmonary capillary wedge pressure at baseline and 1 month after greater splanchnic nerve ablation. Discrepancy in case numbers between baseline and 1 month is explained by either missed or uninterpretable recordings. Means and standard deviation are presented. *Indicates a comparison between baseline and 1 month using a mixed model repeated measures analysis with a p‐value <0.05.

Figure 3

Comparison of baseline New York Heart Association (NYHA) functional class (A), Kansas City Cardiomyopathy Questionnaire (KCCQ) (B), 6‐min walk distance (C) and N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) (D) compared to 1 month after greater splanchnic nerve ablation. Medians and interquartile range are provided unless otherwise specified. *Indicates a Wilcoxon signed rank test (compared to baseline) with a p‐value <0.05.