Three-Year Clinical and Hemodynamic Evaluation of the Hydra Self-Expanding Transcatheter Aortic Valve in Patients With Severe Aortic Stenosis

Background: The Hydra CE study revealed 1-year favorable efficacy of TAVR, showing a large effective orifice area (EOA), low gradient, and acceptable complication rates.

Aims: We evaluated the 3-year clinical and hemodynamic outcomes of Hydra self-expanding transcatheter aortic valve (manufactured by Vascular Innovations Co Ltd, Nonthaburi, Thailand; a subsidiary of Sahajanand Medical Technologies Limited, India) in patients with symptomatic severe aortic stenosis at high or extremely high surgical risk.

Methods: The Hydra CE study was a prospective, multicenter, single-arm study. A total of 157 patients were enrolled in the study, out of whom 54 patients from two centers (Lithuania and Poland) had provided consent for long-term follow-up at recruitment, with a planned 5-year follow-up period. The primary endpoint was all-cause mortality, and patients were followed up for up to 3 years, with an assessment of clinical and echocardiographic outcomes.

Results: Among the 54 patients, the average age was 81.0 ± 4.1 years. The mean STS score was 3.2 ± 2.0%. At 3 years, all-cause mortality had occurred in 14.8% of patients, including 3.7% cardiovascular deaths and 1.9% device-related deaths. There was a progressive enhancement in EOA that is, 0.68 ± 0.15 cm² at baseline to 1.97 ± 0.52 cm² at 3 years (p < 0.001) as well as significant improvement in the mean aortic valve gradient that is, 53.4 ± 14.24 mmHg at baseline to 8.6 ± 2.80 mmHg at 3 years (p < 0.001). New permanent pacemaker implantation rates up to 3-year follow-up was 12.9%.

Conclusion: The 3-year results of the Hydra CE study demonstrated consistent improvements in hemodynamics over time. The study also revealed favorable safety and efficacy trends, along with low occurrences of new permanent pacemaker implantations and paravalvular leaks.