PARIS — An investigational iteration of the MitraClip safely reduced symptomatic moderate to severe tricuspid regurgitation (TR) in the majority of patients in the TRILUMINATE feasibility study.
At 30 days, 86.6% of patients who underwent percutaneous edge-to-edge repair with the TriClip (Abbott Medical) showed at least a one-grade improvement in TR, which met the primary effectiveness end point (97.5% lower confidence limit, 77.3%; performance goal, 35.0%).
One patient had new-onset renal failure, with no deaths, strokes, myocardial infarctions, or valve reinterventions out to 30 days, lead investigator Georg Nickenig, MD, PhD, University Hospital Bonn, Germany, reported in a hotline session here at the Congress of the European Association of Percutaneous Cardiovascular Interventions (EuroPCR) 2019.
"It's a very attractive option, complementary to medical treatment, but we have to test it in a randomized trial with hard end points," he told theheart.org | Medscape Cardiology.
That study is planned, and results on TRILUMINATE's coprimary end point of major adverse events at 6 months will likely be reported at the European Society of Cardiology Congress later this summer, Nickenig said.
About 2.5 million Americans have moderate to severe TR and treatment is typically focused around medical therapy because of high risks associated with standard surgery. Several transcatheter devices, such as the Pascal (Edwards Lifesciences), Trialign (Mitralign Inc.), and Cardioband (Edwards), are showing promise but remain investigational in the United States.
Commenting on the TriClip, Simon Redwood, MD, St. Thomas' Hospital, London, who was not involved in the study, said: "It's early days but it's very exciting because there was 100% success rate, the procedure times were not that long — 75 minutes — so it's a relatively quick procedure with low complications."
"The only thing is the number of clips; only about a third of patients had one clip," he told theheart.org | Medscape Cardiology.
The TRILUMINATE trial was designed to support CE Mark approval in Europe and prospectively enrolled 85 patients with symptomatic at least moderate TR and no indication for left heart valve intervention.
More than half of patients had massive (29%) or torrential (37%) TR, with severe TR present in 29%. Their average age was 77.8 years, 66% were female, and 33% had a previous mitral intervention.
A single clip was used in 20% of patients, two clips in 47.1%, three in 28.2%, and four in 4.7%. At 30 days after clipping, 57% of patients had mild or moderate TR, compared with just 6% at baseline.
Nearly all core lab-adjudicated echocardiographic parameters improved significantly, including effective regurgitant orifice area (0.43 cm2 from 0.68 cm2), regurgitant volume (36.25 mL/beat from 54.87 mL/beat), and regurgitation jet area (9.48 cm2 from 14.62 cm2; P < .0001 for all).
"Maybe as a consequence of this, we saw also reduction in the tricuspid annular diameter [4.05 cm from 4.30 cm]," Nickenig said. "So far, this is speculation whether it is only the pulling force of the clips pulling the valvular wall to the septal, or whether this is already positive remodeling after these early days."
Notably, 80.5% of patients were New York Heart Association functional class 1 or 2 at 30 days, up from 25.6% at baseline (P < .0001).
Kansas City Cardiomyopathy Questionnaire quality-of-life and heart failure symptom scores also increased by a mean of 14.20 points (P < .0001), with a 5-point increase considered clinically meaningful, he said.
With regard to device safety in this early experience, six patients had major bleeds (BARC type 3a) from the vascular access site.
Five patients had single leaflet device attachment and four patients had a mean tricuspid valve gradient of at least 5 mm Hg after 30 days. "We maybe overdid our energy in reducing tricuspid regurgitation but without any clinical sequalae for both patient groups," noted Nickenig.
Asked during a press briefing who would be a candidate for surgery vs edge-to-edge repair, he said surgery is not a good option in these patients, as mortality is as high as 30% in patients with a previous mitral intervention. "The beauty of this device is that it is very easy to use and has a favorable safety profile."
Redwood sounded a similar note. "The advantage of this is that it looks fairly simple and it's based on the MitraClip technology, which we all know and have experience with, so I think it will have an impact," he said. "I don't know if 85 patients is enough to get the CE Mark but it certainly looks very encouraging."
Next-gen, Even Better?
TRILUMINATE shows the TriClip is working properly in the tricuspid position and delivering a therapy opportunity for patients at low procedural risk, said hotline session comoderator Francesco Maisano, MD, University Hospital of Zurich, who developed the Tricinch (4Tech) tricuspid device and performed the first-in-human Cardioband tricuspid repair.
"We have seen zero mortality. This is very important because these patients are very fragile and there is still a big question mark whether treating TR gives any clinical benefit. We see some messaging here but safety is key," he told theheart.org | Medscape Cardiology.
"We already know this is a first-generation [device] waiting for a second-generation with larger clips or maybe independent grasping and, obviously, the biggest question remains patient selection," he said. "We still don't know who are the responders. We are in the phase of learning."
The TriClip was based on the older MitraClip NT system with alterations to the delivery and sheath system to accommodate better alignment to the tricuspid ring and leaftlet. The beauty of the new MitraClip XTR system is it has a longer clip arm — 12 mm instead of 9 mm — and altogether a range that is 5 to 6 mm larger, which helps address the greater variability in gaps and annular dislodgement and dilation in the tricuspid space than in the mitral space, explained Ralph Stephan Von Bardeleben, MD, head, Heart Valve Center, Mainz University Medical Center, Germany.
An extension to the TRILUMINATE trial was performed on the new XTR system, albeit with the old delivery system, in more than 80 patients, he noted.
"What we see in this patient population is that we're more effective in reducing regurgitation, as well as increasing the six-minute-walk, than in the CE Mark trial that was the TRILUMINATE trial," Von Bardeleben told theheart.org | Medscape Cardiology. "The data are under investigation but we also have some hints that the effectiveness in reducing annular dilation in the treatment area is more effective with XTR, as we also see in the EXPAND trial with the mitral valve."
In the tricuspid space, "there will be a dedicated XTR wider-clip device very soon," Nickenig told theheart.org | Medscape Cardiology.
The study is sponsored by Abbott. Nickenig reports relationships with Abbott, AGA, AstraZeneca, Bayer, Berlin Cardiovalve, Chemie, Biosensus, Biotronic, BMS, Boehringer Ingelheim, Daiichi Sankyo, Edwards, Medtronic, Novartis, Pfizer, SanofiAventis, and St. Jude. Redwood reported no relevant financial relationships.
Congress of the European Association of Percutaneous Cardiovascular Interventions (EuroPCR) 2019. Presented May 21, 2019.
Medscape Medical News © 2019
Cite this: Tricuspid Regurgitation Clipping Takes Promising First Step - Medscape - May 22, 2019.