Interatrial Shunt Therapy in Advanced Heart Failure: Outcomes from the Open-Label Cohort of the RELIEVE-HF trial

Published journal: European Journal of Heart Failure (online publish-ahead-of-print 1 April 2024) doi: 10.1002/ejhf.3215.

Dr. Muhammet Tekin

Background:

Heart failure (HF), regardless of left ventricular ejection fraction (LVEF) continues to be a major
public healthcare burden with persisting high morbidity and mortality rates, despite decades of advances in medical therapy and device management. Increased left atrial pressure leading to pulmonary congestion is one of the most common mechanisms precipitating worsening symptoms and acute decompensation. Interatrial shunt devices are under development for decompressing the left atrium in patients with HF by transferring left atrial blood into the right atrium via relatively small shunt (Qp/Qs=1.22). The REducing Lung congestIon symptoms using the v-wavE shunt in adVancEd Heart Failure (RELIEVE-HF) trial is a multicentre pivotal study of the V-Wave Ventura® Interatrial Shunt in symptomatic HF patients, regardless of LVEF.  Two parallel patient cohorts have been recruited: a randomized, double-blind, sham-controlled cohort of 508 patients awaiting completion of primary follow-up, and a prospective, open-label, treatment only roll-in cohort of 97 subjects to assess learning curve and early safety issues.

Objective:

HF outcomes remain poor despite optimal guideline-directed medical therapy. This study evaluated safety, efficacy, and transthoracic echocardiography (TTE) outcomes at 12 months after Ventura shunt implantation in the RELIEVE-HF open-label cohort of 97 patients.

Methods:
Inclusion criteria included at least 1 hospitalization within 1 year or elevated natriuretic peptide levels in symptomatic HF patients despite optimal medical therapy. The safety endpoint was the occurrence of major device-related cardiovascular or neurologic adverse events compared to the prespecified performance goal at day 30. Effectiveness evaluations included the Kansas City Cardiomyopathy Questionnaire (KCCQ) at baseline, 1, 3, 6, and 12 months and TTE parameters at baseline and 12 months. In total, 97 patients were included in the study and implantations were performed in 64 centers. Average age was 70±11 years, 97% were in New York Heart Association class III, and half had LVEF ?40%.

Results:

Safety endpoint was achieved in the study (event rate 0%, p<0.001). KCCQ overall summary score was improved by 12–16 points during the follow up (all p<0.004), with similar outcomes in patients with reduced and preserved LVEF. At 12 months, left (p=0.02) and right (p=0.038) ventricular end-systolic and end-diastolic volumes were reduced. LVEF(p=0.009), right ventricular fractional area change (p<0.001) and tricuspid annular plane systolic excursion (p<0.001) improved.

Conclusion:

The roll-in phase of the RELIEVE-HF study revealed that the Ventura interatrial shunt device improved functional capacity, quality of life and exercise capacity in patients with advanced HF, with a high safety and procedural success rate during the 1 year follow-up. Quantitative echocardiographic follow-up demonstrated beneficial effects on LV and RV structure and function independent of baseline LVEF and suggested that the 5.1 mm diameter shunt size successfully reduced LV preload without RV volume overloading or worsening renal function. These results supported the potential of shunt devices in the treatment of HF

Interpretation:
The results of the roll-in cohort of the RELIEVE-HF trial have shown that in patients with advanced HF, interatrial shunting improves quantitative echocardiographic findings, functional capacity and quality of life without serious safety and procedural issues, suggesting a favorable outcome for the RELIEVE-HF trial.