Percutaneous aortic valve replacement using a W-model valved stent: a preliminary feasibility study in sheep

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Interventional Cardiology

Background:

• Aortic valve stenosis necessitates advanced treatment options.
• Percutaneous aortic valve replacement (PAVR) shows promise but requires further clinical validation.
• A novel W-model valved stent was developed to address limitations in current PAVR devices.

Purpose of the Study:

• To evaluate the feasibility and safety of percutaneous implantation of a W-model valved stent.
• To assess the device's performance in the native aortic valve position in a preclinical model.

Main Methods:

• A self-expanding nitinol stent with a W-model configuration and porcine pericardium valves was implanted in six sheep.
• Catheter-based delivery via the right common iliac artery under fluoroscopic guidance.
• Post-procedure evaluation included angiography, ventriculography, and anatomical assessment.

Main Results:

• Successful aortic valve replacement in the beating heart was achieved in four out of six sheep.
• Procedure failure occurred in two sheep due to coronary orifice occlusion and severe aortic regurgitation.
• Anatomical evaluation revealed no damage to the aortic intima or coronary orifice obstruction.

Conclusions:

• Percutaneous aortic valve replacement with the W-model valved stent in a beating heart is technically possible.
• The study highlights the need for larger sample sizes and extended follow-up periods to fully ascertain safety and efficacy.
• Further investigation is essential to optimize this novel valved stent for clinical application.