Novel balloon-expandable valve shows encouraging results in pooled analysis

A pooled analysis of first-in-human and early feasibility studies demonstrates promising 30-day clinical and echocardiographic outcomes with the novel DurAVR transcatheter heart valve (THV) in patients with small aortic annuli (SAA).

“The DurAVR THV is a balloon-expandable valve featuring a single-piece biomimetic leaflet design,” said the investigators. “[In our study,] we observed a high rate of VARC-3*–defined technical success and early clinical safety and efficacy and favourable core-lab-assessed echocardiographic haemodynamic outcomes [in patients with SAA at 30 days].”

The study included 100 participants (mean age 77 years, 78 percent women, mean STS** risk score 4.7 percent) from the EMBARK (n=74), US-EFS (n=15), and EU-EFS (n=11) cohorts. All patients received a small DurAVR THV (diameter 21–24 mm). Ninety-one percent of patients had a tricuspid aortic valve, and 9 percent had a type 1 bicuspid aortic valve phenotype.

SAA was defined as a CT-based aortic annular area of 346–452 mm². The mean aortic annulus area was 404 mm², with a mean annulus diameter of 22.7 mm. The baseline mean aortic valve gradient was 48.1 mm Hg, and left ventricular ejection fraction was 58 percent. [EuroIntervention 2026;22:e150-e160]

The overall technical success rate was 93 percent. Of note, periprocedural complications were only encountered in EMBARK, which, according to the researchers, reflects early device and operator experience. “Subsequent refinements to the valve design, compliance of the inflation balloon, delivery system, and expandable sheath profile were implemented.” After which, a 100-percent technical success rate was achieved in the last 50 consecutive implants (including the two EFS cohorts) due to the absence of major periprocedural complications.

The overall rate of new permanent pacemaker implantation was 6 percent. There was marked symptomatic improvement, with a 12-point increase from the baseline KCCQ*** score. Moreover, 70 percent of participants reported an improvement in NYHA*** classification.

The stroke rate was 2 percent. There were no deaths reported. The rates of major vascular complications and bleeding (type 2–4) were ≤7 percent. Again, none of these complications were observed in the EFS cohorts.

Valve performance

Ninety-one percent of patients achieved device success. One participant developed a late external iliac artery thrombus that required vascular intervention, and another had a residual mean transprosthetic gradient >20 mm Hg due to leaflet thrombosis detected on post-TAVI^# CT imaging.

The mean transprosthetic gradient was 8.2 mm Hg, with a mean effective orifice area of 2.2 cm² and a mean Doppler velocity index of 0.60. The rate of prosthesis-patient mismatch (PPM) was 3 percent, and none had greater than mild paravalvular leak.

Suboptimal results

Patients with SAA undergoing TAVI usually have suboptimal results, including elevated transprosthetic gradients, increased PPM, and early bioprosthetic valve failure, which may be due to TAV design. [J Am Coll Cardiol 2018;72:2701-2711; J Am Coll Cardiol 2018;72:2712-2716; N Engl J Med 2019;380:1695-1705; N Engl J Med 2024;390:1959-1971]

In this study, the DurAVR THV showed high rates of technical and device success, along with favourable haemodynamic outcomes at 30 days, including a low PPM rate in patients with SAA.

“Longer-term follow-up in larger cohorts is needed to confirm these encouraging early results … Ongoing randomized controlled trials will further evaluate its advantages relative to current-generation THVs and explore how its biomimetic design may improve patient outcomes,” the investigators concluded.