Inter-atrial shunt in RELIEVE-HF improves symptoms in HFrEF, but not HFpEF
The late-breaking RELIEVE-HF trial, presented at the American College of Cardiology (ACC) 2024 meeting, sheds new light on the potential of inter-atrial shunts in addressing heart failure symptoms.
This double-blind, randomized 508-patient trial focused on the use of the V-Wave Ventura inter-atrial shunt in patients with heart failure with reduced (HFrEF) or preserved (HFpEF) left ventricular ejection fraction. While the trial's primary effectiveness endpoint was neutral, showing neither significant benefit nor harm, further analysis revealed distinct outcomes based on ejection fraction status.
"So the bottom line is that we concluded that while shunt treatment was safe, it didn't provide effectiveness over a broad range of patients with ejection fractions of any degree. However, it was of cardiovascular benefit in patients with reduced ejection fraction, it was very, very positive. Whereas in patients with preserved ejection fraction, it produced harm," Gregg Stone, MD, professor of medicine at the Icahn School of Medicine, Mt. Sinai, who presented the findings, said.
Despite the results being neutral, stone added that the study revealed promising results for HFrEF patients. This included a 45% decrease in cardiovascular events, including death. The need for left ventricular assist device (LVAD) implantation or heart transplantation was also reduced. Stone said HFrEF patients experienced significant cardiovascular benefits, including a 52% reduction in heart failure hospitalizations and favorable trends in mortality and need for advanced interventions like heart transplant or LVAD.
In contrast, HFpEF patients saw no improvement. In fact, they may have experienced additional harm, shown in an increased rate of heart failure hospitalizations and mortality. Stone said this should serve as a red flag for trials that look at using shunts in these types of heart failure patients. Interestingly, the quality of life part of the study found all patients felt better, showing a clear placebo effect, even in patients whose conditions worsened and required hospitalization.
"They got better whether they got the shunt or whether they got a placebo procedure. So a big placebo effect of blinding patients. For example, in the preserved ejection fraction group, even though the patients who got the shunt were having twice as many hospitalizations for severe heart failure and were dying three times more commonly, they still thought they were feeling better. So it really raises questions as how to interpret this particular metric in blinded heart failure trials and by implication, even open label trials because of this marked placebo effect," Stone explained.
Watch the video above to hear more and see the key slides from Stone's presentation.