One-year outcomes of the TRILUMINATE trial show improved symptoms, function, and quality of life after clip-based transcatheter repair of the often overlooked tricuspid valve.
The 1-year findings from the 85-patient, single-arm study, reported today in the Journal of the American College of Cardiology and presented at virtual conferences last summer, confirm positive 6-month data that led to an April CE mark approval for the TriClip (Abbott) device in the European Union.
Follow-up among the older (mean age, 77.8 years), symptomatic cohort at high surgical risk showed that 87% (54 of 62 evaluable patients) had tricuspid regurgitation (TR) severity reduced by at least one grade at 1 year, with 70% (44/63 patients) having moderate or less TR.
A full 83% of patients were New York Heart Association functional class I/II, up from 31% at baseline (P < .0001).
The repair was also associated with robust quality-of-life improvements, reduced hospitalizations, and consistent signs of reverse right ventricular (RV) remodeling, the investigators report.
RV end diastolic diameter decreased from 5.28 cm at baseline to 4.79 cm at 1-year follow-up (P < .0001), and RV function, measured by tricuspid annular plane systolic excursion, increased from 1.44 cm to 1.59 cm (P = .0002).
"I'd also like to highlight that mortality was only 7.1% after 1 year and this is certainly much lower than expected and as compared to a natural history cohort of patients with tricuspid regurgitation," for whom mortality was about 15% to 25%, lead author Philipp Lurz, MD, PhD, University of Leipzig Heart Center, Germany, told theheart.org | Medscape Cardiology.
Although the TriClip device remains investigational in the United States, tricuspid valve repair with the TriClip is currently reimbursed in Germany, he noted.
"All the signals from the field point toward the right direction, attesting that patients benefit from a clinical point of view. Having said that, obviously, we have to wait until we have results from a randomized trial but this TRILUMINATE trial — the first of its kind — sort of sets the scene for the big pivotal trial," Lurz said.
The ongoing 700-patient TRILUMINATE Pivotal Trial compares the TriClip device with standard medical therapy in symptomatic patients who are at intermediate or higher risk for surgery. It also includes a single arm for patients with more complex tricuspid disease and a roll-in for physicians requiring additional training prior to beginning randomization. The primary end point is a composite of all-cause mortality or tricuspid repair surgeries, heart failure hospitalizations, and quality-of-life at 12 months. The estimated primary completion date is August 2022.
The open-label TRI-FR trial is also scheduled to start this month in Europe and will compare best medical therapy alone or on top of TriClip repair in 300 patients with severe tricuspid disease. The primary end point is the Milton Packer clinical composite score at 12 months. Primary completion is set for January 2022.
In an accompanying editorial, TRI-FR principal investigator Erwan Donal, MD, PhD, Centre Hospitalier Universitaire (CHU) Rennes, France, and colleagues write that the 1-year TRIMULINATE results are "pretty exciting." They not only show a sustained reduction in TR severity between 30 days and 1 year, but "also a decrease in right ventricular dimensions and, more importantly, a clinical benefit."
That said, questions remain, like the relation between TR reduction and clinical benefit, Donal told theheart.org | Medscape Cardiology. "Sometimes we are a little bit surprised because we have a very good result in terms of correction of the tricuspid regurg thanks to the treatment, but when we discuss with the patient, they don't feel better; and sometimes [it's] the opposite."
The editorial stresses the need to distinguish between different phenotypes of secondary TR and suggests the results challenge current pathophysiologic concepts, much like the discordant COAPT and MITRA-FR trials of the MitraClip did for mitral valve regurgitation.
"Thanks to MITRA-FR and COAPT, we realize that secondary mitral regurgitation is something that is quite complex and 'til now we don't really understand who are the patients that should be absolutely treated and who shouldn't be treated by the clip," Donal said. "I think — and I'm not the only one — that we might have the same issue with the tricuspid regurg because, like in the case of mitral regurgitation, there are several phenotypes of tricuspid regurg and probably the response to treatment between phenotypes might be different."
Transcatheter repair with the TriClip is not reimbursed in France and patients should not be treated outside clinical trials until the randomized results are known, Donal said. "We are really at the very beginning of a new story about the understanding of who these patients are with tricuspid regurg and probably there are different phenotypes of tricuspid regurg and different answers to treatment."
Lurz agreed that it's important to optimize patient selection and differentiate between ventricular functional TR and atrial functional TR, but noted that although patients with longstanding atrial fibrillation and preserved RV function do extremely well after TriClip repair, those "at the other end of the spectrum" with severe pulmonary hypertension can also benefit.
"The strongest signal so far — and that's been shown by other groups — in terms of who will benefit and who will not is the question of how much you are able to reduce tricuspid regurg by the intervention. So, almost irrespective of what you have as a substrate, when you can bring down TR from grade 4 to 1," clinical improvement is certain, he said. "There's no doubt about that. These patients, they come back and tell you they have a different life."
The study was funded by Abbott. Lurz has been a consultant to Abbott Structural Heart, Edwards Lifesciences, and Medtronic. Donal has received consultant fees from Abbott.
Medscape Medical News © 2021
Cite this: TRILUMINATE in Print: TriClip's Promise Awaits Further Validation - Medscape - Jan 18, 2021.