Reverse Remodeling and Higher Stroke Volume With TEER: TRILUMINATE

LONDON, England—An echocardiographic analysis of patients with severe tricuspid regurgitation (TR) treated with transcatheter edge-to-edge repair (TEER) shows that the quality-of-life improvements with TriClip (Abbott) extend to patients who have a dilated or dysfunctional right ventricle (RV). 

Additionally, investigators provided some evidence to explain the benefit of treatment, reporting that TEER led to favorable RV reverse remodeling as well as an increase in forward stroke volume.

“We know that with tricuspid regurgitation, the majority of these patients have significant dysfunction and dilatation by the time they come to us,” lead investigator Nadira Hamid, MD (Minneapolis Heart institute Foundation, MN), who presented the results last week at PCR London Valves, told TCTMD. However, based on these data, there is no need to exclude such patients from tricuspid TEER, she said.

“We all know the RV size matters,” Hamid continued, noting an enlarged RV is associated with worse clinical outcomes. “What’s interesting here is that TriClip affects quality of life, irrespective of the RV size.”

Similarly, roughly one-quarter of patients in TRILUMINATE had impaired RV function, but quality of life improved in these patients, too. With full transcatheter tricuspid valve replacement (TTVR), operators need to be more cautious in patients with RV dysfunction, she said, noting that those with severe dysfunction have been excluded from clinical trials, including the TRISCEND II study.

Improved Quality of Life With TEER

The TRILUMINATE pivotal trial previously showed that treating severe TR with tricuspid TEER was superior to medical therapy for reducing the primary composite outcome of all-cause death or tricuspid valve surgery; hospitalization for heart failure (HF); and improvements in quality of life. The benefits were driven by the quality-of-life gains, but nevertheless led to US Food and Drug Administration approval of TriClip in April 2024.

Among the 285 patients treated with TEER, 73% had RV dilation on baseline echocardiography (RV basal diameter index ≥ 24.5) and roughly 25% had moderate-to-severe RV dysfunction when assessed by the tricuspid annular plane systolic excursion (TAPSE). By the fractional area change (FAC), which estimates global RV systolic function, 25% had more than moderate dysfunction and 10% had severe dysfunction.  

Baseline RV size was associated with a higher risk of HF hospitalizations or mortality in both those treated with TEER and those randomized to medical therapy. As noted, TriClip improved quality of life irrespective of baseline RV size, with numerically greater gains in those with RV dilation. There was no difference in HF hospitalizations or mortality between those with normal, mild, or moderate/severe RV dysfunction assessed by TAPSE or FAC.

In terms of RV reverse remodeling, patients in the entire study cohort with residual trace/mild TR at 1 year had significantly larger reductions in RV end-diastolic diameter (RVEDD) compared with those with residual severe or greater TR. Similarly, those with at least a 2-grade reduction in TR at 1 year had the largest reduction in RVEDD. Investigators also observed favorable changes in stroke volume based on reductions in TR, with increases in RV outflow tract stroke volume seen in those with at least a 1-grade improvement in TR. The vast majority of patients who had improvements in TR at 1 year were treated with TEER.  

“If you can achieve trace or mild TR, that’s the goal,” Hamid told TCTMD. “You will get that RV reverse remodeling. To the question of whether we should be aiming for it, my answer is yes.”

If you can achieve trace or mild TR, that’s the goal. Nadira Hamid

During the discussion after the hot-line presentation, Jörg Hausleiter, MD (Ludwig-Maximilians Universität München, Munich, Germany), said that while investigators did not show an association between impaired RV function and HF hospitalizations or mortality, this may only be because of how it was assessed. “TAPSE is not the correct measure to assess right ventricular function,” he said. If you use other methods, such as 3D-CT, then “you’ll see a significant impact on outcomes.”

Julia Grapsa, MD, PhD (Guy’s and St Thomas’ NHS Trust, London, England), emphasized that RV dilation plays an important role in patient outcomes, and she questioned whether the larger RV predisposes patients to RV-pulmonary artery (RV-PA) uncoupling.

Hamid acknowledged that measuring RV function with TAPSE and FAC has limitations, and that other treatment modalities, including those documenting RV-PA coupling, can better understand the changes in RV function associated with severe TR and tricuspid valve interventions. Investigators recently published an MRI and CT imaging substudy from TRILUMINATE, she said, noting that there were significant reductions in RVEDD and RV ejection fraction with TEER.

“These are all key parameters to understand that reducing TR not only improved the quality of life, but also the RV reverse remodeling,” said Hamid. “That’s how patients get better.”