TTVR system holds promise for severe tricuspid regurgitation

Transcatheter tricuspid valve replacement (TTVR) using the EVOQUE system was feasible and had an acceptable safety profile in patients with severe tricuspid regurgitation (TR), according to initial data from the pivotal TRISCEND II trial.

“TRISCEND II met its primary composite safety endpoint,” noted lead investigator Dr Susheel Kodali from Columbia University Irving Medical Center, New York, New York, US, at TCT 2023.

At 30 days, the rate of composite major adverse events (MAEs) with the TTVR device plus optimal medical therapy (OMT) was 27.4 percent which, according to Kodali, is less than the historical rate of 43.8 percent.

The most common adjudicated MAE was arrhythmia and conduction disorder requiring permanent pacing (14.7 percent) followed by severe bleeding (10.5 percent). The rate of cardiovascular death was 3.2 percent.

Significant TR grade reductions

Looking at the overall 6-month rates, nearly all patients on TTVR-OMT had moderate or less TR vs 21.6 percent in the OMT-alone arm (difference, 77.1 percent; p<0.001).

When stratifying by TR grade, about 80 percent of TTVR-OMT recipients had none/trace TR, 16.0 percent had mild TR, 4.9 percent had moderate TR, and only 1.2 percent had severe TR at 6 months. In the OMT-alone arm, 27 percent still had severe TR, while more than half had massive or torrential TR.

To put it further into context, the 6-month rates of massive or torrential TR with OMT alone were similar to baseline levels. In the TTVR-OMT arm, baseline TR grades also fell between the levels of severe and torrential, with none having trace to moderate TR severity.

Superior QoL, functional outcomes

There were also superior quality of life (QoL) outcomes with TTVR-OMT than with OMT alone, generating a win ratio of 4.6 in favour of the former. “Treatment of severe TF with the system resulted in meaningful improvements and functional status and symptoms at 6 months,” said Kodali.

Mean changes in KCCQ* summary score were greater with TTVR-OMT vs OMT alone, both at 30 days (17.0 vs 1.2 points) and 6 months (21.5 vs 3.7 points). A similar trend favouring TTVR-OMT was seen in terms of 6MWD** at both timepoints (-4.7 vs -14.5 m [30 days] and 10.6 vs -20.3 m [6 months]).

TTVR-OMT also rendered greater improvements in NYHA*** Class vs OMT alone. At 6 months, 90 percent of TTVR-OMT recipients were NYHA Class I/II – a far cry from the baseline (22.6 percent) and OMT-alone rates (34.2 percent). More than 10 percent of those on OMT alone were NYHA Class IV; with TTVR-OMT, the corresponding rate was only 1.3 percent.

Addresses an unmet need

“Treatment options for TR are limited, with medical therapy being suboptimal and surgery having high rates of morbidity and mortality,” said Kodali. “There is an unmet need for transcatheter solutions that provide treatment options at lower risk and result in improved outcomes.”

The total cohort comprised 400 patients who were randomized 2:1 to either the TTVR device plus OMT or OMT alone. This analysis included the first 150 randomized and treated patients (mean age 78.8 years, ~80 percent female).

“[This] system is able to fully replace the tricuspid valve, virtually eliminating TR in a wide range of anatomies,” said Professor Philipp Lurz from the University of Mainz, Germany, in a press release. “The significant [QoL improvements] are remarkable, now offering a therapy to many patients who previously had no treatment options.” [www.edwards.com/gb/newsroom/news/2023-10-19-edwards-evoque-transcatheter-tricuspid-valve-repla, accessed November 10, 2023]

“[Unlike transcatheter edge-to-edge repair,] this device effectively eliminates TR in a vast majority of patients despite the presence of massive or torrential TR at baseline in >50 percent of the population,” said Kodali.

It remains to be seen whether this will translate into an improvement in mortality rate. “Important clinical and echocardiographic endpoints, including mortality and heart failure hospitalization, from the full cohort … will be presented in the future,” Kodali concluded.